1
|
Berlińska A, Świątkowska-Stodulska R. Clinical use of thyroglobulin: not only thyroid cancer. Endocrine 2024; 84:786-799. [PMID: 38182855 PMCID: PMC11208243 DOI: 10.1007/s12020-023-03658-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 12/10/2023] [Indexed: 01/07/2024]
Abstract
Thyroglobulin (TG) is a dimeric glycoprotein produced exclusively by mature thyroid tissue and stored within the follicular lumen. It is essential for the organification of iodine and the production of thyroid hormones. The concentration of TG in the bloodstream varies between individuals and depends on factors such as thyroid mass, stimulation of the gland by thyrotropin or autoantibodies, and tissue destruction. TG is essential to monitor patients with differentiated thyroid cancer; however, its use is not limited only to this clinical entity. Measurement of circulating TG can provide better insight into numerous clinical scenarios, such as destructive thyroiditis, presence of ectopic thyroid tissue, thyroid trauma, factitious thyrotoxicosis, or iodine nutrition. Lately, TG has found its new clinical use in immune checkpoint-related thyroid dysfunction. TG measurement should be performed carefully in patients with antithyroglobulin antibodies due to possible laboratory interferences. In this review, we offer a summary of current knowledge about the clinical use of TG and the implications it brings to daily practice.
Collapse
Affiliation(s)
- Agata Berlińska
- Department of Endocrinology and Internal Medicine, Faculty of Medicine, Medical University of Gdańsk, Gdańsk, Poland.
| | - Renata Świątkowska-Stodulska
- Department of Endocrinology and Internal Medicine, Faculty of Medicine, Medical University of Gdańsk, Gdańsk, Poland
| |
Collapse
|
2
|
Fischer L, Andersson M, Braegger C, Herter-Aeberli I. Iodine intake in the Swiss population 100 years after the introduction of iodised salt: a cross-sectional national study in children and pregnant women. Eur J Nutr 2024; 63:573-587. [PMID: 38141138 PMCID: PMC10899291 DOI: 10.1007/s00394-023-03287-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 11/23/2023] [Indexed: 12/24/2023]
Abstract
PURPOSE The Swiss voluntary salt iodisation programme has successfully prevented iodine deficiency for 100 years, but dietary habits are changing and today only one-third of processed foods contain iodised salt. We aimed to monitor the current iodine status in children and pregnant women. METHODS We conducted a nationwide cross-sectional study in children (6-12 years) and pregnant women and measured the urinary iodine concentration (UIC) in spot urine samples. We estimated the iodine intake using UIC and urinary creatinine concentration (UCC) and determined the prevalence of intakes below the average requirement (AR) using the SPADE method. We measured dried blood spot (DBS) thyroglobulin (Tg), TSH and total T4 in pregnant women. RESULTS The median UIC was 127 μg/L (bootstrapped 95% CI 119, 140, n = 362) in children and 97 μg/L (bootstrapped 95% CI 90, 106, n = 473) in pregnant women. The estimated prevalence of inadequate iodine intake (< 65 μg/day) was 5.4% (bootstrapped 95% CI 0.0, 14.6) in children. Half (47%) of the women consumed iodine-containing multivitamin and mineral supplements (≥ 150 μg/day). Compared to non-users, users had higher median UIC (129 vs. 81 μg/L, P < 0.001), lower prevalence of inadequacy (< 160 μg/day; 0.2 vs. 31%) and lower DBS-Tg (23 vs. 29 μg/L, P < 0.001). All women were euthyroid. CONCLUSIONS The Swiss diet and current salt fortification provides adequate iodine intake in children, but not in all pregnant women. Iodine supplements cover the dietary gap in pregnancy but are not universally consumed. Therefore, improved use of iodised salt in processed foods is desired to ensure adequate iodine intake in all population groups. This trial was registered at clinicaltrials.gov as NCT04524013.
Collapse
Affiliation(s)
- Lena Fischer
- Nutrition Research Unit, Children's Research Centre, University Children's Hospital Zurich - Eleonore Foundation, Steinwiesstrasse 75, 8032, Zurich, Switzerland.
- Laboratory of Nutrition and Metabolic Epigenetics, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland.
| | - Maria Andersson
- Nutrition Research Unit, Children's Research Centre, University Children's Hospital Zurich - Eleonore Foundation, Steinwiesstrasse 75, 8032, Zurich, Switzerland
| | - Christian Braegger
- Nutrition Research Unit, Children's Research Centre, University Children's Hospital Zurich - Eleonore Foundation, Steinwiesstrasse 75, 8032, Zurich, Switzerland
| | - Isabelle Herter-Aeberli
- Laboratory of Nutrition and Metabolic Epigenetics, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland
| |
Collapse
|
3
|
Groufh-Jacobsen S, Abel MH, Brantsæter AL, Andersson M, Meyer HE, Henjum S. National monitoring of iodine, sodium, and vitamin D status in toddlers and women of childbearing age - results and lessons learned from a pilot study in Norway. Food Nutr Res 2023; 67:9088. [PMID: 37691743 PMCID: PMC10492227 DOI: 10.29219/fnr.v67.9088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 06/12/2023] [Accepted: 07/05/2023] [Indexed: 09/12/2023] Open
Abstract
Background Norway is lacking a population-based national monitoring program for iodine, sodium, and vitamin D status. Objective The aim of this study was to pilot-test a study design for collecting biological samples from a country-representative sample of 2-year-old children and their mothers and to report results for iodine, salt, and vitamin D at baseline, before initiation of salt iodization in Norway. Design In a cross-sectional study, we recruited 2-year-old children and their mothers during the routine 2-year check-up through 38 randomly selected health clinics in 2021. Spot urine samples were analyzed for iodine, creatinine, and sodium, and dried blood spots from the mothers were analyzed for thyroglobulin (Tg) and 25-hydroxyvitamin D (25(OH)D). Results We aimed at including 400 mother-child pairs but recruited only 55 pairs. Major challenges were closed health clinics due to the COVID-19 pandemic, lack of motivation of the health personnel to prioritize recruiting, missing information about non-participation, and high workload for participants. The median urinary iodine concentration (UIC) was 123 (95% CI: 76, 228) µg/L in the toddlers and 83 (95% CI: 72, 99) µg/L in the mothers. The median urinary sodium concentration (UNaC) was 62 (95% CI: 37, 91) mmol/L in the toddlers and 93 (95% CI: 77, 107) mmol/L in the mothers. Of the mothers, 18% had levels of 25(OH)D <50 nmol/L (suboptimal status). Discussion and conclusion Lessons learned from the pilot study will be used to design a national monitoring program for toddlers and women of childbearing age in Norway. The results indicate that 2-year-old children and women of childbearing age in Norway may have inadequate iodine intakes at the group level, while for vitamin D, most of the mothers had adequate status.
Collapse
Affiliation(s)
- Synne Groufh-Jacobsen
- Department of Nutrition and Public Health, Faculty of Health and Sport Science, University of Agder, Kristiansand, Norway
| | - Marianne Hope Abel
- Department of Physical Health and Ageing, Norwegian Institute of Public Health, Oslo, Norway
| | - Anne Lise Brantsæter
- Department of Food Safety, Division of Climate and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Maria Andersson
- Nutrition Research Unit, University Children’s Hospital Zurich, Zurich, Switzerland
| | - Haakon E. Meyer
- Department of Physical Health and Ageing, Norwegian Institute of Public Health, Oslo, Norway
| | - Sigrun Henjum
- Department of Nursing and Health Promotion, Faculty of Health Science, Oslo Metropolitan University, Oslo, Norway
| |
Collapse
|
4
|
Dineva M, Rayman MP, Levie D, Hunziker S, Guxens M, Peeters RP, Murcia M, Rebagliato M, Irizar A, Jimeno-Romero A, Sunyer J, Korevaar TIM, Bath SC. Exploration of thyroglobulin as a biomarker of iodine status in iodine-sufficient and mildly iodine-deficient pregnant women. Eur J Nutr 2023; 62:2139-2154. [PMID: 36973522 PMCID: PMC10349736 DOI: 10.1007/s00394-023-03131-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Accepted: 02/27/2023] [Indexed: 03/29/2023]
Abstract
PURPOSE Urinary iodine-to-creatinine ratio (UI/Creat) reflects recent iodine intake but has limitations for assessing habitual intake. Thyroglobulin (Tg) concentration, which increases with thyroid size, appears to be an indicator of longer-term iodine status in children and adults, however, less is known in pregnancy. This study investigated the determinants of serum-Tg in pregnancy and its use as an iodine-status biomarker in settings of iodine-sufficiency and mild-to-moderate deficiency. METHODS Stored blood samples and existing data from pregnant women from the Netherlands-based Generation R (iodine-sufficient) and the Spain-based INMA (mildly-to-moderately iodine-deficient) cohorts were used. Serum-Tg and iodine status (as spot-urine UI/Creat) were measured at median 13 gestational weeks. Using regression models, maternal socio-demographics, diet and iodine-supplement use were investigated as determinants of serum-Tg, as well as the association between UI/Creat and serum-Tg. RESULTS Median serum-Tg was 11.1 ng/ml in Generation R (n = 3548) and 11.5 ng/ml in INMA (n = 1168). When using 150 µg/g threshold for iodine deficiency, serum-Tg was higher in women with UI/Creat < 150 vs ≥ 150 µg/g (Generation R, 12.0 vs 10.4 ng/ml, P = 0.010; INMA, 12.8 vs 10.4 ng/ml, P < 0.001); after confounder adjustment, serum-Tg was still higher when UI/Creat < 150 µg/g (regression coefficients: Generation R, B = 0.111, P = 0.050; INMA, B = 0.157, P = 0.010). Iodine-supplement use and milk intake were negatively associated with serum-Tg, whereas smoking was positively associated. CONCLUSION The association between iodine status and serum-Tg was stronger in the iodine-deficient cohort, than in the iodine-sufficient cohort. Serum-Tg might be a complementary (to UI/Creat) biomarker of iodine status in pregnancy but further evidence is needed.
Collapse
Affiliation(s)
- Mariana Dineva
- Department of Nutritional Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH, UK
| | - Margaret P Rayman
- Department of Nutritional Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH, UK
| | - Deborah Levie
- The Generation R Study Group, Erasmus University Medical Centre, Rotterdam, The Netherlands
- Department of Internal Medicine, Academic Centre for Thyroid Diseases, Erasmus University Medical Centre, Rotterdam, The Netherlands
- Department of Child and Adolescent Psychiatry/Psychology, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands
- ISGlobal, Barcelona, Spain
- Universitat Pompeu Fabra, Barcelona, Spain
- Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Instituto de Salud Carlos III, Madrid, Spain
| | - Sandra Hunziker
- Human Nutrition Laboratory, Institute of Food, Nutrition, and Health, ETH Zurich, Zurich, Switzerland
| | - Mònica Guxens
- Department of Child and Adolescent Psychiatry/Psychology, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands
- ISGlobal, Barcelona, Spain
- Universitat Pompeu Fabra, Barcelona, Spain
- Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Instituto de Salud Carlos III, Madrid, Spain
| | - Robin P Peeters
- Department of Internal Medicine, Academic Centre for Thyroid Diseases, Erasmus University Medical Centre, Rotterdam, The Netherlands
| | - Mario Murcia
- Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Instituto de Salud Carlos III, Madrid, Spain
- Servicio de Análisis de Sistemas de Información Sanitaria, Conselleria de Sanitat, Generalitat Valenciana, Valencia, Spain
- Epidemiology and Environmental Health Joint Research Unit, FISABIO-Universitat Jaume I-Universitat de València, Valencia, Spain
| | - Marisa Rebagliato
- Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Instituto de Salud Carlos III, Madrid, Spain
- Epidemiology and Environmental Health Joint Research Unit, FISABIO-Universitat Jaume I-Universitat de València, Valencia, Spain
- Predepartamental Unit of Medicine, University Jaume I, Castelló, Spain
| | - Amaia Irizar
- Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Instituto de Salud Carlos III, Madrid, Spain
- BIODONOSTIA Health Research Institute, Donostia‑San Sebastián, Spain
- Department of Preventive Medicine and Public Health, Faculty of Medicine and Nursery, University of the Basque Country (UPV/EHU), Leioa, Spain
| | - Alba Jimeno-Romero
- BIODONOSTIA Health Research Institute, Donostia‑San Sebastián, Spain
- Department of Preventive Medicine and Public Health, Faculty of Medicine and Nursery, University of the Basque Country (UPV/EHU), Leioa, Spain
| | - Jordi Sunyer
- ISGlobal, Barcelona, Spain
- Universitat Pompeu Fabra, Barcelona, Spain
- Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Instituto de Salud Carlos III, Madrid, Spain
- Parc Salut Mar-IMIM, Barcelona, Spain
| | - Tim I M Korevaar
- The Generation R Study Group, Erasmus University Medical Centre, Rotterdam, The Netherlands
- Department of Internal Medicine, Academic Centre for Thyroid Diseases, Erasmus University Medical Centre, Rotterdam, The Netherlands
| | - Sarah C Bath
- Department of Nutritional Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH, UK.
| |
Collapse
|
5
|
Optimizing Growth: The Case for Iodine. Nutrients 2023; 15:nu15040814. [PMID: 36839172 PMCID: PMC9959690 DOI: 10.3390/nu15040814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/29/2023] [Accepted: 02/03/2023] [Indexed: 02/08/2023] Open
Abstract
Iodine is an essential micronutrient and component of thyroid hormone. An adequate dietary iodine intake is critical to maintain and promote normal growth and development, especially during vulnerable life stages such as pregnancy and early infancy. The role of iodine in cognitive development is supported by numerous interventional and observational studies, and when iodine intake is too low, somatic growth is also impaired. This can be clearly seen in cases of untreated congenital hypothyroidism related to severe iodine deficiency, which is characterized, in part, by a short stature. Nevertheless, the impact of a less severe iodine deficiency on growth, whether in utero or postnatal, is unclear. Robust studies examining the relationship between iodine and growth are rarely feasible, including the aspect of examining the effect of a single micronutrient on a process that is reliant on multiple nutrients for optimal success. Conversely, excessive iodine intake can affect thyroid function and the secretion of optimal thyroid hormone levels; however, whether this affects growth has not been examined. This narrative review outlines the mechanisms by which iodine contributes to the growth process from conception onwards, supported by evidence from human studies. It emphasizes the need for adequate iodine public health policies and their robust monitoring and surveillance, to ensure coverage for all population groups, particularly those at life stages vulnerable for growth. Finally, it summarizes the other micronutrients important to consider alongside iodine when seeking to assess the impact of iodine on somatic growth.
Collapse
|
6
|
Sprayed microcapsules of minerals for fortified food. J Funct Foods 2023. [DOI: 10.1016/j.jff.2023.105401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
|
7
|
Businge CB, Musarurwa HT, Longo-Mbenza B, Kengne AP. The prevalence of insufficient iodine intake in pregnancy in Africa: a systematic review and meta-analysis. Syst Rev 2022; 11:231. [PMID: 36303220 PMCID: PMC9615360 DOI: 10.1186/s13643-022-02072-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 09/12/2022] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Fortification of foodstuffs with iodine, mainly through iodization of salt, which commenced in several African countries after 1995 is the main method for mitigating iodine deficiency in Africa. We assessed the degree of iodine nutrition in pregnancy across Africa before and after the implementation of national iodine fortification programs (CRD42018099434). METHODS Electronic databases and gray literature were searched for baseline data before implementation of population-based iodine supplementation and for follow-up data up to September 2020. R-metamedian and metamean packages were used to pool country-specific median urinary iodine concentration (UIC) estimates and derived mean UIC from studies with similar features. RESULTS Of 54 African countries, 23 had data on iodine nutrition in pregnancy mostly from subnational samples. Data before 1995 showed that severe iodine deficiency was prevalent in pregnancy with a pooled pregnancy median UIC of 28.6 μg/L (95% CI 7.6-49.5). By 2005, five studies revealed a trend towards improvement in iodine nutrition state in pregnancy with a pooled pregnancy median UIC of 174.1 μg/L (95% CI 90.4-257.7). Between 2005 and 2020 increased numbers of national and subnational studies revealed that few African countries had sufficient, while most had mildly inadequate, and some severely inadequate iodine nutrition in pregnancy. The pooled pregnancy median UIC was 145 μg/L (95% CI 126-172). CONCLUSION Improvement in iodine nutrition status in pregnancy following the introduction of fortification of foodstuffs with iodine in Africa is sub-optimal, exposing a large proportion of pregnant women to the risk of iodine deficiency and associated disorders. SYSTEMATIC REVIEW REGISTRATION PROSPERO CRD42018099434.
Collapse
Affiliation(s)
- Charles Bitamazire Businge
- Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa. .,Department of Obstetrics and Gynaecology, Faculty of Health Sciences, Walter Sisulu University, Private Bag x1 WSU, Mthatha, 5117, South Africa.
| | - Hannibal Tafadzwa Musarurwa
- Department of Biological Sciences, Faculty of Health Sciences, Walter Sisulu University, Private Bag x1 WSU, Mthatha, 5117, South Africa
| | | | - Andre Pascal Kengne
- Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Faculty of Medicine, University of Kinshasa, Kinshasa, Democratic Republic of Congo.,Non-Communicable Disease Research Unit, South African Medical Research Council, Cape Town, South Africa
| |
Collapse
|
8
|
Andersson M, Braegger CP. The Role of Iodine for Thyroid Function in Lactating Women and Infants. Endocr Rev 2022; 43:469-506. [PMID: 35552681 PMCID: PMC9113141 DOI: 10.1210/endrev/bnab029] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Indexed: 12/18/2022]
Abstract
Iodine is a micronutrient needed for the production of thyroid hormones, which regulate metabolism, growth, and development. Iodine deficiency or excess may alter the thyroid hormone synthesis. The potential effects on infant development depend on the degree, timing, and duration of exposure. The iodine requirement is particularly high during infancy because of elevated thyroid hormone turnover. Breastfed infants rely on iodine provided by human milk, but the iodine concentration in breast milk is determined by the maternal iodine intake. Diets in many countries cannot provide sufficient iodine, and deficiency is prevented by iodine fortification of salt. However, the coverage of iodized salt varies between countries. Epidemiological data suggest large differences in the iodine intake in lactating women, infants, and toddlers worldwide, ranging from deficient to excessive intake. In this review, we provide an overview of the current knowledge and recent advances in the understanding of iodine nutrition and its association with thyroid function in lactating women, infants, and toddlers. We discuss risk factors for iodine malnutrition and the impact of targeted intervention strategies on these vulnerable population groups. We highlight the importance of appropriate definitions of optimal iodine nutrition and the need for more data assessing the risk of mild iodine deficiency for thyroid disorders during the first 2 years in life.
Collapse
Affiliation(s)
- Maria Andersson
- Nutrition Research Unit, University Children's Hospital Zurich, CH-8032 Zürich, Switzerland
| | - Christian P Braegger
- Nutrition Research Unit, University Children's Hospital Zurich, CH-8032 Zürich, Switzerland
| |
Collapse
|
9
|
Mullan K, McMullan P, Kayes L, McCance D, Hunter A, Woodside JV. Thyroglobulin levels among iodine deficient pregnant women living in Northern Ireland. Eur J Clin Nutr 2022; 76:1542-1547. [PMID: 35513447 DOI: 10.1038/s41430-022-01144-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 04/01/2022] [Accepted: 04/05/2022] [Indexed: 11/09/2022]
Abstract
BACKGROUND Iodine deficiency has re-emerged among pregnant cohorts in the UK. Thyroglobulin (Tg) is a protein produced uniquely by the thyroid gland which appears to mount a U-shaped response to extremes of iodine status. Tg has been suggested as an alternative marker for chronic iodine deficiency but the value of Tg in pregnancy has not been fully elucidated. A recent non-European study suggested a median Tg ≤10 µg/L with <3% of values >44 µg/L was indicative of sufficiency in the second trimester of pregnancy. METHODS We measured serum Tg levels in each trimester in 241 pregnant women living in Northern Ireland, a population with mild iodine deficiency at all stages of pregnancy as defined by urinary iodine concentration (UIC) and iodine: creatinine ratio (ICR). Women with Tg antibodies (6% in 1st trimester) were excluded. RESULTS The median UIC in this cohort was in the deficient range at 73, 94 and 117 µg/L in sequential trimesters (adequacy ≥ 150 µg/L). Corresponding median Tg levels were 19, 16 and 16 µg/L respectively. Median Tg for all samples was 17 μg/L (IQR 11-31) suggestive of iodine deficiency. Tg was >44 μg/L in 14.3%, 9.4% and 12.4% of women in sequential trimesters respectively. Women with either UIC/ICR below the cut-offs 150 µg/L and 150 µg/g creatinine had higher Tg concentrations in 1st and 2nd trimester (p < 0.01; p < 0.001) but not in 3rd trimester. CONCLUSION This study adds to the evolving evidence that Tg measurement is of value in reflecting iodine status in pregnancy.
Collapse
Affiliation(s)
- Karen Mullan
- Royal Victoria Hospital (Regional Centre for Endocrinology and Diabetes), Belfast, Antrim, UK
| | - Paul McMullan
- Royal Victoria Hospital (Regional Centre for Endocrinology and Diabetes), Belfast, Antrim, UK
| | - Lucy Kayes
- Royal Victoria Hospital (Regional Centre for Endocrinology and Diabetes), Belfast, Antrim, UK.
| | - David McCance
- Royal Victoria Hospital (Regional Centre for Endocrinology and Diabetes), Belfast, Antrim, UK
| | - Alyson Hunter
- Royal Jubilee Maternity Hospital, Royal Victoria Hospital, Belfast, Antrim, UK
| | - Jayne V Woodside
- Centre for Public Health, Institute of Clinical Science, Queens University Belfast, Belfast, UK
| |
Collapse
|
10
|
Allen LH, Hampel D, Shahab-Ferdows S, Andersson M, Barros E, Doel AM, Eriksen KG, Christensen SH, Islam M, Kac G, Keya FK, Michaelsen KF, de Barros Mucci D, Njie F, Peerson JM, Moore SE. The Mothers, Infants, and Lactation Quality (MILQ) Study: A Multi-Center Collaboration. Curr Dev Nutr 2021; 5:nzab116. [PMID: 34712893 PMCID: PMC8546155 DOI: 10.1093/cdn/nzab116] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 09/02/2021] [Accepted: 09/08/2021] [Indexed: 12/19/2022] Open
Abstract
Little valid information is available on human milk nutrient concentrations, especially for micronutrients (MNs), and there are no valid reference values (RVs) across lactation. In this multi-center collaborative study, RVs will be established for human milk nutrients across the first 8.5 mo postpartum. Well-nourished, unsupplemented women in Bangladesh, Brazil, Denmark, and The Gambia (n = 250/site) were recruited during the third trimester of pregnancy. Milk, blood, saliva, urine, and stool samples from mothers and their infants are collected identically at 3 visits (1-3.49, 3.5-5.99, 6.0-8.49 mo postpartum). Milk analyses include macronutrients, selected vitamins, trace elements and minerals, iodine, metabolomics, amino acids, human milk oligosaccharides, and bioactive peptides. We measure milk volume; maternal and infant diets, anthropometry, and morbidity; infant development, maternal genome, and the infant and maternal microbiome. RVs will be constructed based on methods for the WHO Child Growth Standards and the Intergrowth-21st Project. This trial was registered at clinical trials.gov as NCT03254329.
Collapse
Affiliation(s)
- Lindsay H Allen
- USDA, Agricultural Research Service (ARS) Western Human Nutrition Research Center, Davis, CA, USA
- Department of Nutrition, University of California, Davis, CA, USA
| | - Daniela Hampel
- USDA, Agricultural Research Service (ARS) Western Human Nutrition Research Center, Davis, CA, USA
- Department of Nutrition, University of California, Davis, CA, USA
| | - Setareh Shahab-Ferdows
- USDA, Agricultural Research Service (ARS) Western Human Nutrition Research Center, Davis, CA, USA
- Department of Nutrition, University of California, Davis, CA, USA
| | - Maria Andersson
- Nutrition Research Unit, University Children's Hospital Zurich, Zurich, Switzerland
| | - Erica Barros
- Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Kamilla Gehrt Eriksen
- Department of Nutrition, Exercise, and Sports, University of Copenhagen, Copenhagen, Denmark
| | | | - Munirul Islam
- Nutrition and Clinical Services Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr, b), Dhaka, Bangladesh
| | - Gilberto Kac
- Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Farhana Khanam Keya
- Nutrition and Clinical Services Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr, b), Dhaka, Bangladesh
| | - Kim F Michaelsen
- Department of Nutrition, Exercise, and Sports, University of Copenhagen, Copenhagen, Denmark
| | | | - Fanta Njie
- Medical Research Council Unit The Gambia at London School of Hygiene & Tropical Medicine, Fajara, The Gambia, West Africa
| | - Janet M Peerson
- USDA, Agricultural Research Service (ARS) Western Human Nutrition Research Center, Davis, CA, USA
| | - Sophie E Moore
- Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Medical Research Council Unit The Gambia at London School of Hygiene & Tropical Medicine, Fajara, The Gambia, West Africa
| |
Collapse
|
11
|
Purdue-Smithe AC, Männistö T, Reische E, Kannan K, Kim UJ, Suvanto E, Surcel HM, Gissler M, Mills JL. Iodine and thyroid status during pregnancy and risk of stillbirth: A population-based nested case-control study. MATERNAL AND CHILD NUTRITION 2021; 18:e13252. [PMID: 34350728 PMCID: PMC8710109 DOI: 10.1111/mcn.13252] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 06/21/2021] [Accepted: 07/13/2021] [Indexed: 11/26/2022]
Abstract
Prior research suggests that severe iodine deficiency in pregnancy may be associated with stillbirth. However, the relationship between mild to moderate iodine insufficiency, which is prevalent even in developed countries, and risk of stillbirth is unclear. We thus examined associations of iodine status and risk of stillbirth in a prospective population‐based nested case–control study in Finland, a mild to moderately iodine insufficient population. Stillbirth cases (n = 199) and unaffected controls (n = 249) were randomly selected from among all singleton births in Finland from 2012 to 2013. Serum samples were collected between 10 and 14 weeks gestation and analysed for iodide, thyroglobulin (Tg) and thyroid‐stimulating hormone (TSH). Odds ratios (ORs) and 95% confidence intervals (CIs) for stillbirth were estimated using logistic regression. After adjusting for maternal age, prepregnancy body mass index, socio‐economic status and other factors, neither high nor low serum iodide was associated with risk of stillbirth (Q1 vs. Q2–Q3 OR = 0.92, 95% CI = 0.78–1.09; Q4 vs. Q2–Q3 OR = 0.78; 95% CI = 0.45–1.33). Tg and TSH were also not associated with risk of stillbirth in adjusted models. Maternal iodine status was not associated with stillbirth risk in this mildly to moderately iodine‐deficient population. Tg and TSH, which reflect functional iodine status, were also not associated with stillbirth risk. The lack of associations observed between serum iodide, TSH and Tg and risk of stillbirth is reassuring, given that iodine deficiency in pregnancy is prevalent in developed countries.
Collapse
Affiliation(s)
- Alexandra C Purdue-Smithe
- Division of Intramural Population Health Research, National Institutes of Health, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland, USA
| | - Tuija Männistö
- Northern Finland Laboratory Center NordLab, Oulu University Hospital, Oulu, Finland
| | - Elijah Reische
- Division of Intramural Population Health Research, National Institutes of Health, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland, USA
| | - Kurunthachalam Kannan
- Department of Pediatrics and Department of Environmental Medicine, New York University School of Medicine, New York, New York, USA
| | - Un-Jung Kim
- Department of Earth and Environmental Sciences, University of Texas at Arlington, Arlington, Texas, USA
| | - Eila Suvanto
- Oulu University Hospital, Department of Children and Women and Oulu University Medical Faculty PEDEGO Research Unit, Medical Research Center, Oulu, Finland
| | - Heljä-Marja Surcel
- Biobank Borealis of Northern Finland, Oulu University Hospital, Oulu, Finland.,Faculty of Medicine, University of Oulu, Oulu, Finland
| | - Mika Gissler
- Information Services Department, Finnish Institute of Health and Welfare, Helsinki, Finland.,Department of Neurobiology, Karolinska Institute, Stockholm, Sweden
| | - James L Mills
- Division of Intramural Population Health Research, National Institutes of Health, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland, USA
| |
Collapse
|
12
|
Businge CB, Longo-Mbenza B, Kengne AP. Iodine nutrition status in Africa: potentially high prevalence of iodine deficiency in pregnancy even in countries classified as iodine sufficient. Public Health Nutr 2021; 24:3581-3586. [PMID: 32744219 PMCID: PMC8369456 DOI: 10.1017/s1368980020002384] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To assess the burden of iodine deficiency in pregnancy in Africa using estimated pregnancy median urinary iodine concentration (pMUIC). DESIGN pMUIC for each African country was estimated using a regression equation derived by correlating the school-age children (SAC) median UIC (mUIC) and pMUIC from countries around the globe, and the SAC mUIC data for African countries obtained from the Iodine Global Network (IGN) 2017 and 2019 Score cards. SETTING Iodine deficiency was endemic in many African countries before the introduction of iodine fortification, mainly through universal salt iodisation programmes about 25 years ago. There is a scarcity of data on the level of iodine nutrition in pregnancy in Africa. Women living in settings with pMUIC below 150 µg/l are at risk of iodine deficiency-related pregnancy complications. PARTICIPANTS Fifty of the fifty-five African countries that had data on iodine nutrition status. RESULTS A cut-off school age mUIC ≤ 175 µg/l is correlated with insufficient iodine intake in pregnancy (pregnancy mUIC ≤ 150 μg/l). Twenty-two African countries had SAC mUIC < 175 μg/l, which correlated with insufficient iodine intake during pregnancy (pMUIC < 150 μg/l). However, nine of these twenty-two countries had adequate iodine intake based on SAC mUIC. CONCLUSIONS There is likely a high prevalence of insufficient iodine intake in pregnancy, including in some African countries classified as having adequate iodine intake in the general population. A SAC mUIC ≤ 175 µg/l predicts insufficient iodine intake among pregnant women in these settings.
Collapse
Affiliation(s)
- Charles Bitamazire Businge
- Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Department of Obstetrics and Gynaecology, Faculty of Health Sciences, Walter Sisulu University, Mthatha, South Africa
| | - Benjamin Longo-Mbenza
- Faculty of Medicine, University of Kinshasa, Kinshasa, Democratic Republic of Congo
- Lomo University of Research, Kinshasa, Democratic Republic of Congo
| | - Andre Pascal Kengne
- Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Non-Communicable Research Unit, South African Medical Research Council, Cape Town, South Africa
| |
Collapse
|
13
|
Consumption of multiple micronutrients or small-quantity lipid-based nutrient supplements containing iodine at the recommended dose during pregnancy, compared with iron and folic acid, does not affect women's urinary iodine concentration in rural Malawi: a secondary outcome analysis of the iLiNS DYAD trial. Public Health Nutr 2021; 24:3049-3057. [PMID: 33054890 PMCID: PMC9884741 DOI: 10.1017/s1368980020003250] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
OBJECTIVES Inadequate iodine intake during pregnancy increases the risk of neonatal morbidity and mortality. We aimed to evaluate whether prenatal supplements containing iodine affect urinary iodine concentrations (UIC) of pregnant women in Malawi. DESIGN A randomised controlled trial. Pregnant women (n 1391) were assigned to consume 60 mg/d Fe and 400 µg/d folic acid (IFA) or 18 vitamins and minerals including 250 µg/d iodine (MMN) or 20 g/d small-quantity lipid-based nutrient supplements (SQ-LNS) with similar nutrient contents as MMN group, plus macronutrients (LNS) until childbirth. In a sub-study (n 317), we evaluated group geometric mean urinary iodine concentration (UIC) (µg/L) at 36 weeks of gestation controlling for baseline UIC and compared median (baseline) and geometric mean (36 weeks) UIC with WHO cut-offs: UIC < 150, 150-249, 250-499 and ≥500 reflecting insufficient, adequate, above requirements and excessive iodine intakes, respectively. SETTING Mangochi District, Malawi. PARTICIPANTS Women ≤20 weeks pregnant. RESULTS Groups had comparable background characteristics. At baseline, overall median (Q1, Q3) UIC (319 (167, 559)) suggested iodine intakes above requirements. At 36 weeks, the geometric mean (95 % CI) UIC of the IFA (197 (171, 226)), MMN (212 (185, 243)) and LNS (220 (192, 253)) groups did not differ (P = 0·53) and reflected adequate intakes. CONCLUSIONS In this setting, provision of supplements containing iodine at the recommended dose to pregnant women with relatively high iodine intakes at baseline, presumably from iodised salt, has no impact on the women's UIC. Regular monitoring of the iodine status of pregnant women in such settings is advisable. Clinicaltrials.gov identifier: NCT01239693.
Collapse
|
14
|
Zimmermann MB, Andersson M. GLOBAL ENDOCRINOLOGY: Global perspectives in endocrinology: coverage of iodized salt programs and iodine status in 2020. Eur J Endocrinol 2021; 185:R13-R21. [PMID: 33989173 PMCID: PMC8240726 DOI: 10.1530/eje-21-0171] [Citation(s) in RCA: 82] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 05/14/2021] [Indexed: 12/18/2022]
Abstract
Iodine deficiency has multiple adverse effects on growth and development. Diets in many countries cannot provide adequate iodine without iodine fortification of salt. In 2020, 124 countries have legislation for mandatory salt iodization and 21 have legislation allowing voluntary iodization. As a result, 88% of the global population uses iodized salt. For population surveys, the urinary iodine concentration (UIC) should be measured and expressed as the median, in μg/L. The quality of available survey data is high: UIC surveys have been done in 152 out of 194 countries in the past 15 years; in 132 countries, the studies were nationally representative. The number of countries with adequate iodine intake has nearly doubled from 67 in 2003 to 118 in 2020. However, 21 countries remain deficient, while 13 countries have excessive intakes, either due to excess groundwater iodine, or over-iodized salt. Iodine programs are reaching the poorest of the poor: of the 15 poorest countries in the world, 10 are iodine sufficient and only 3 (Burundi, Mozambique and Madagascar) remain mild-to-moderately deficient. Nigeria and India have unstable food systems and millions of malnourished children, but both are iodine-sufficient and population coverage with iodized salt is a remarkable 93% in both. Once entrenched, iodine programs are often surprisingly durable even during national crises, for example, war-torn Afghanistan and Yemen are iodine-sufficient. However, the equity of iodized salt programs within countries remains an important issue. In summary, continued support of iodine programs is needed to sustain these remarkable global achievements, and to reach the remaining iodine-deficient countries.
Collapse
Affiliation(s)
- Michael B Zimmermann
- Department of Health Sciences and Technology, Human Nutrition Laboratory, ETH Zürich, Zürich, Switzerland
- Iodine Global Network, Ottawa, Ontario, Canada
| | - Maria Andersson
- Iodine Global Network, Ottawa, Ontario, Canada
- Nutrition Research Unit, University Children’s Hospital Zürich, Zürich, Switzerland
| |
Collapse
|
15
|
Prpić M, Franceschi M, Vidranski V, Andersson M, Zimmermann MB, Hunziker S, Milošević M, Kusić Z, Jukić T. IODINE STATUS AND THYROID FUNCTION IN LACTATING WOMEN AND INFANTS - A SURVEY IN THE ZAGREB AREA, CROATIA. Acta Clin Croat 2021; 60:259-267. [PMID: 34744276 PMCID: PMC8564841 DOI: 10.20471/acc.2021.60.02.12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 09/24/2019] [Indexed: 11/24/2022] Open
Abstract
Lactating women (LW) and infants have high dietary iodine requirements and are at risk of iodine deficiency. The aim of the study was to assess iodine status and thyroid function in LW and their breastfed infants in Zagreb, Croatia. The study included 133 LW and breastfed infant pairs. Urinary iodine concentration (UIC) and thyroid function parameters were measured in all subjects. In LW, breast milk iodine concentration (BMIC) was measured and iodine and salt rich food frequency questionnaire data were collected. Results of analysis indicated that 99.2% of the LW used iodized salt in household and 20.4% used iodine-containing vitamin and mineral supplements. Median (IQR) UIC was 75 µg/L (19.0-180.5 µg/L) in LW and 234 µg/L (151.0-367.5 µg/L) in infants, whereas BMIC was 121 µg/kg (87.8-170.8 µg/kg). Multivariate regression analysis revealed BMIC to be a significant predictor of infant UIC (p<0.001). Positive correlation was recorded between LW and infant thyroid function. This was the first study in Croatia demonstrating BMIC to be a reliable biomarker of iodine status during lactation and predicting iodine intake in breastfed infants. The study confirmed that mandatory salt iodization in Croatia ensured sufficient dietary iodine for LW and optimal iodine intake for breastfed infants via breast milk.
Collapse
Affiliation(s)
| | - Maja Franceschi
- 1Department of Oncology and Nuclear Medicine, Sestre milosrdnice University Hospital Centre, Zagreb, Croatia; 2School of Medicine, University of Zagreb, Zagreb, Croatia; 3Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia; 4Division of Gastroenterology and Nutrition, Zurich University Children's Hospital, Zurich, Switzerland; 5Iodine Global Network, Ottawa, Ontario, Canada; 6Human Nutrition Laboratory, Institute of Food, Nutrition and Health, Zurich ETH, Zurich, Switzerland; 7University of Zagreb, School of Medicine, Andrija Štampar School of Public Health, WHO Collaborative Centre for Occupational Health, Zagreb, Croatia; 8Croatian Academy of Sciences and Arts, Zagreb, Croatia
| | - Valentina Vidranski
- 1Department of Oncology and Nuclear Medicine, Sestre milosrdnice University Hospital Centre, Zagreb, Croatia; 2School of Medicine, University of Zagreb, Zagreb, Croatia; 3Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia; 4Division of Gastroenterology and Nutrition, Zurich University Children's Hospital, Zurich, Switzerland; 5Iodine Global Network, Ottawa, Ontario, Canada; 6Human Nutrition Laboratory, Institute of Food, Nutrition and Health, Zurich ETH, Zurich, Switzerland; 7University of Zagreb, School of Medicine, Andrija Štampar School of Public Health, WHO Collaborative Centre for Occupational Health, Zagreb, Croatia; 8Croatian Academy of Sciences and Arts, Zagreb, Croatia
| | - Maria Andersson
- 1Department of Oncology and Nuclear Medicine, Sestre milosrdnice University Hospital Centre, Zagreb, Croatia; 2School of Medicine, University of Zagreb, Zagreb, Croatia; 3Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia; 4Division of Gastroenterology and Nutrition, Zurich University Children's Hospital, Zurich, Switzerland; 5Iodine Global Network, Ottawa, Ontario, Canada; 6Human Nutrition Laboratory, Institute of Food, Nutrition and Health, Zurich ETH, Zurich, Switzerland; 7University of Zagreb, School of Medicine, Andrija Štampar School of Public Health, WHO Collaborative Centre for Occupational Health, Zagreb, Croatia; 8Croatian Academy of Sciences and Arts, Zagreb, Croatia
| | - Michael B Zimmermann
- 1Department of Oncology and Nuclear Medicine, Sestre milosrdnice University Hospital Centre, Zagreb, Croatia; 2School of Medicine, University of Zagreb, Zagreb, Croatia; 3Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia; 4Division of Gastroenterology and Nutrition, Zurich University Children's Hospital, Zurich, Switzerland; 5Iodine Global Network, Ottawa, Ontario, Canada; 6Human Nutrition Laboratory, Institute of Food, Nutrition and Health, Zurich ETH, Zurich, Switzerland; 7University of Zagreb, School of Medicine, Andrija Štampar School of Public Health, WHO Collaborative Centre for Occupational Health, Zagreb, Croatia; 8Croatian Academy of Sciences and Arts, Zagreb, Croatia
| | - Sandra Hunziker
- 1Department of Oncology and Nuclear Medicine, Sestre milosrdnice University Hospital Centre, Zagreb, Croatia; 2School of Medicine, University of Zagreb, Zagreb, Croatia; 3Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia; 4Division of Gastroenterology and Nutrition, Zurich University Children's Hospital, Zurich, Switzerland; 5Iodine Global Network, Ottawa, Ontario, Canada; 6Human Nutrition Laboratory, Institute of Food, Nutrition and Health, Zurich ETH, Zurich, Switzerland; 7University of Zagreb, School of Medicine, Andrija Štampar School of Public Health, WHO Collaborative Centre for Occupational Health, Zagreb, Croatia; 8Croatian Academy of Sciences and Arts, Zagreb, Croatia
| | - Milan Milošević
- 1Department of Oncology and Nuclear Medicine, Sestre milosrdnice University Hospital Centre, Zagreb, Croatia; 2School of Medicine, University of Zagreb, Zagreb, Croatia; 3Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia; 4Division of Gastroenterology and Nutrition, Zurich University Children's Hospital, Zurich, Switzerland; 5Iodine Global Network, Ottawa, Ontario, Canada; 6Human Nutrition Laboratory, Institute of Food, Nutrition and Health, Zurich ETH, Zurich, Switzerland; 7University of Zagreb, School of Medicine, Andrija Štampar School of Public Health, WHO Collaborative Centre for Occupational Health, Zagreb, Croatia; 8Croatian Academy of Sciences and Arts, Zagreb, Croatia
| | - Zvonko Kusić
- 1Department of Oncology and Nuclear Medicine, Sestre milosrdnice University Hospital Centre, Zagreb, Croatia; 2School of Medicine, University of Zagreb, Zagreb, Croatia; 3Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia; 4Division of Gastroenterology and Nutrition, Zurich University Children's Hospital, Zurich, Switzerland; 5Iodine Global Network, Ottawa, Ontario, Canada; 6Human Nutrition Laboratory, Institute of Food, Nutrition and Health, Zurich ETH, Zurich, Switzerland; 7University of Zagreb, School of Medicine, Andrija Štampar School of Public Health, WHO Collaborative Centre for Occupational Health, Zagreb, Croatia; 8Croatian Academy of Sciences and Arts, Zagreb, Croatia
| | - Tomislav Jukić
- 1Department of Oncology and Nuclear Medicine, Sestre milosrdnice University Hospital Centre, Zagreb, Croatia; 2School of Medicine, University of Zagreb, Zagreb, Croatia; 3Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia; 4Division of Gastroenterology and Nutrition, Zurich University Children's Hospital, Zurich, Switzerland; 5Iodine Global Network, Ottawa, Ontario, Canada; 6Human Nutrition Laboratory, Institute of Food, Nutrition and Health, Zurich ETH, Zurich, Switzerland; 7University of Zagreb, School of Medicine, Andrija Štampar School of Public Health, WHO Collaborative Centre for Occupational Health, Zagreb, Croatia; 8Croatian Academy of Sciences and Arts, Zagreb, Croatia
| |
Collapse
|
16
|
Iodine nutrition: Disorders, monitoring and policies. ADVANCES IN FOOD AND NUTRITION RESEARCH 2021; 96:365-415. [PMID: 34112358 DOI: 10.1016/bs.afnr.2021.01.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Iodine is an essential mineral nutrient and an integral component of thyroid hormones. Iodine deficiency is typically associated with goiter, but can have more serious health implications. Adequate iodine status is important for normal brain development. Iodine deficiency in utero or in early life can cause severe neurological and cognitive impairment. Over the last three decades, global efforts have reduced the prevalence of iodine deficiency disorders (IDD) in many areas of the world with implementation of nutrition policies and programs such as "salt" iodization. However, in a number of areas iodine deficiency is still widespread. Iodine deficiency in remote regions with high poverty will be more difficult to eradicate. Efforts to eliminate IDD in affected areas and sustaining successful iodine programs will be a priority given the substantial public health and economic benefits. A key component will be periodic monitoring of population iodine status to ensure sufficient intakes and the absence of excessive intakes. Median urinary iodine concentration (UIC), a validated biomarker for assessing population iodine status, will facilitate monitoring. Research validating "usual" UIC for use in combination with the Estimated Average Requirement cut-point method will expand its utility and allow accurate determination of the prevalence of inadequate intakes in populations. Further research on the development of biomarkers for assessment of individual iodine status for routine patient care will be important.
Collapse
|
17
|
Manousou S, Eggertsen R, Hulthén L, Filipsson Nyström H. A randomized, double-blind study of iodine supplementation during pregnancy in Sweden: pilot evaluation of maternal iodine status and thyroid function. Eur J Nutr 2021; 60:3411-3422. [PMID: 33620551 PMCID: PMC8354996 DOI: 10.1007/s00394-021-02515-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 02/05/2021] [Indexed: 12/01/2022]
Abstract
Purpose Pregnant women in Sweden are mildly iodine deficient. We investigated the effect of daily iodine supplementation on the iodine and thyroid status of pregnant women. Methods In this pilot, randomized, double-blind trial, 200 thyroid-healthy pregnant women were recruited at mean (standard deviation) pregnancy week 8.85 (1.62) and assigned (1:1) to daily intake of a multivitamin tablet with or without 150 μg of iodine. Urine and serum samples were collected at baseline and once during the second and third trimesters. Urinary iodine concentration (UIC), serum thyroglobulin (Tg), thyroid-stimulating hormone (TSH), free thyroxine (FT4), and thyroid peroxidase antibodies (TPOabs) were analyzed. Neonatal TSH data were collected. UIC and Tg were also analyzed in a group of 89 thyroid-healthy non-pregnant women of reproductive age (WRA). Results At baseline, the intervention and the control groups had similar median UIC (interquartile range (IQR)): 110 μg/L (74–119) and 111 μg/L (66–168), respectively. The intervention group reached iodine sufficiency with median UIC (IQR) 139 μg/L (89–234) and 136 μg/L (91–211) in the second and third trimester, respectively, without significant difference from the lower limit of the recommended range, i.e. 150–250 μg/L (p = 0.42 and p = 0.87, respectively). The intervention group had higher median UIC and lower median Tg compared to the control group during the second (p < 0.001 and p = 0.019, respectively) and third trimester (p < 0.001 and p = 0.003, respectively), whereas thyroid hormones, serum TPOabs, and neonatal TSH were similar. The WRA group presented median UIC (IQR) 65 μg/L (30–98) and median Tg (IQR) 18 μg/L (13–27).
Conclusion A daily supplement containing 150 μg of iodine to a group of pregnant women with mild iodine deficiency improved the iodine status from mild ID to iodine sufficiency. This improvement seems to have had a positive impact on maternal thyroglobulin. This study is now under extension to investigate the children’s neuropsychological development.
Trial registration ClinicalTrials.gov Identifier NCT02378246, May 3, 2015, retrospectively registered.
Collapse
Affiliation(s)
- Sofia Manousou
- Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden. .,Frölunda Specialist Hospital, Marconigatan 31, 42144, Västra Frölunda, Sweden.
| | - Robert Eggertsen
- School of Public Health and Community Medicine/General Medicine, R and D Centre Gothenburg and Södra Bohuslän, University of Gothenburg, Göteborg, Sweden
| | - Lena Hulthén
- Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden
| | - Helena Filipsson Nyström
- Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden.,Department of Endocrinology, Sahlgrenska University Hospital, Göteborg, Sweden.,Wallenberg Center for Molecular and Translational Medicine, University of Gothenburg and Sahlgrenska University Hospital, Göteborg, Sweden
| |
Collapse
|
18
|
BÍLEK R, DVOŘÁKOVÁ M, GRIMMICHOVÁ T, JISKRA J. Iodine, Thyroglobulin and Thyroid Gland. Physiol Res 2020; 69:S225-S236. [DOI: 10.33549/physiolres.934514] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Iodine is essential in the biosynthesis of thyroid hormones that affect metabolic processes in the organism from the prenatal state to the elderly. The immediate indicator of iodine intake is the concentration of iodine in urine, but the indicator of iodine intake in the longer term of several months is thyroglobulin (Tg). Tg negatively correlated with increasing intake of iodine in population that do not suffer from thyroid disease, while a more than adequate to excessive iodine intake leads to an increase in Tg. The dependence of Tg on iodine can be described by a U-shaped curve. Thyroglobulin in serum is elevated in thyroid disease mainly in hyperthyroidism (diagnosis E05 of WHO ICD-10 codes) and in goiter (diagnosis E04 of WHO ICD-10 codes). Tg values decrease below 20 µg/l after effective treatment of patients with thyroid disease. Thyroglobulin may thus be an indicator of thyroid stabilization and the success of the thyroid gland treatment.
Collapse
Affiliation(s)
- R. BÍLEK
- Institute of Endocrinology, Prague, Czech Republic
| | | | | | | |
Collapse
|
19
|
Eriksen KG, Andersson M, Hunziker S, Zimmermann MB, Moore SE. Effects of an Iodine-Containing Prenatal Multiple Micronutrient on Maternal and Infant Iodine Status and Thyroid Function: A Randomized Trial in The Gambia. Thyroid 2020; 30:1355-1365. [PMID: 32183608 PMCID: PMC7482118 DOI: 10.1089/thy.2019.0789] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Background: Iodine supplementation is recommended to pregnant women in iodine-deficient populations, but the impact in moderate iodine deficiency is uncertain. We assessed the effect of an iodine-containing prenatal multiple micronutrient (MMN) supplement in a rural Gambian population at risk of moderate iodine deficiency. Materials and Methods: This study uses data and samples collected as a part of the randomized controlled trial Early Nutrition and Immune Development (ENID; ISRCTN49285450) conducted in Keneba, The Gambia. Pregnant women (<20 weeks gestation) were randomized to either a daily supplement of MMNs containing 300 μg of iodine or an iron and folic acid (FeFol) supplement. Randomization was double blinded (participants and investigators). The coprimary outcomes were maternal urinary iodine concentration (UIC) and serum thyroglobulin (Tg), assessed at baseline and at 30 weeks' gestation. Secondary outcomes were maternal serum thyrotropin (TSH), total triiodothyronine (TT3), total thyroxine (TT4) (assessed at baseline and at 30 weeks' gestation), breast milk iodine concentration (BMIC) (assessed at 8, 12, and 24 weeks postpartum), infant serum Tg (assessed at birth [cord], 12, and 24 weeks postpartum), and serum TSH (assessed at birth [cord]). The effect of supplementation was evaluated using mixed effects models. Results: A total of 875 pregnant women were enrolled between April 2010 and February 2015. In this secondary analysis, we included women from the MMN (n = 219) and FeFol (n = 219) arm of the ENID trial. At baseline, median (interquartile range or IQR) maternal UIC and Tg was 51 μg/L (33-82) and 22 μg/L (12-39), respectively, indicating moderate iodine deficiency. Maternal MMN supplement increased maternal UIC (p < 0.001), decreased maternal Tg (p < 0.001), and cord blood Tg (p < 0.001) compared with FeFol. Maternal thyroid function tests (TSH, TT3, TT4, and TT3/TT4 ratio) and BMIC did not differ according to maternal supplement group over the course of the study. Median (IQR) BMIC, maternal UIC, and infant Tg in the MMN group were 51 μg/L (35-72), 39 μg/L (25-64), and 87 μg/L (59-127), respectively, at 12 weeks postpartum, and did not differ between supplement groups. Conclusions: Supplementing moderately iodine-deficient women during pregnancy improved maternal iodine status and reduced Tg concentration. However, the effects were not attained postpartum and maternal and infant iodine nutrition remained inadequate during the first six months after birth. Consideration should be given to ensuring adequate maternal status through pregnancy and lactation in populations with moderate deficiency.
Collapse
Affiliation(s)
- Kamilla G. Eriksen
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
- Address correspondence to: Kamilla G. Eriksen, PhD, Department of Nutrition, Exercise and Sports, University of Copenhagen, Rolighedsvej 26, 1958 Frederiksberg, Copenhagen, Denmark
| | - Maria Andersson
- Division of Gastroenterology and Nutrition, Children's Research Centre, University Children's Hospital Zurich, Zurich, Switzerland
| | - Sandra Hunziker
- Human Nutrition Laboratory, Institute of Food, Nutrition, and Health, ETH Zurich, Zurich, Switzerland
| | - Michael B. Zimmermann
- Human Nutrition Laboratory, Institute of Food, Nutrition, and Health, ETH Zurich, Zurich, Switzerland
| | - Sophie E. Moore
- Department of Women and Children's Health, King's College London, London, United Kingdom
| |
Collapse
|
20
|
Current iodine nutrition status in Poland (2017): is the Polish model of obligatory iodine prophylaxis able to eliminate iodine deficiency in the population? Public Health Nutr 2020; 23:2467-2477. [PMID: 32476639 DOI: 10.1017/s1368980020000403] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
OBJECTIVE The monitoring of the populations' iodine status is an essential part of successful programmes of iodine deficiency elimination. The current study aimed at the evaluation of current iodine nutrition in school children, pregnant and lactating women as a marker of the effectiveness and sustainability of mandatory iodine prophylaxis in Poland. DESIGN The following iodine nutrition indicators were used: urinary iodine concentration (UIC) (all participants) and serum thyroglobulin (pregnant and lactating women). SETTING The study was conducted in 2017 within the National Health Programme in five regions of Poland. PARTICIPANTS The research included 300 pregnant women, 100 lactating women and 1000 school children (aged 6-12 years). RESULTS In pregnant women, median UIC was 111·6 µg/l; there was no significant difference in median UIC according to the region of residence. In 8 % of pregnant women, thyroglobulin level was >40 ng/ml (median thyroglobulin 13·3 ng/ml). In lactating women, median UIC was 68·0 µg/l. A significant inter-regional difference was noted (P = 0·0143). In 18 % of breastfeeding women, thyroglobulin level was >40 ng/ml (median thyroglobulin 18·5 ng/ml). According to the WHO criteria, the investigated sample of pregnant and lactating women was iodine-deficient. Median UIC in school children was 119·8 µg/l (with significant inter-regional variation; P = 0·0000), which is consistent with iodine sufficiency. Ninety-four children (9·4 %) had UIC < 50 µg/l. CONCLUSIONS Mandatory iodisation of household salt in Poland has led to a sustainable optimisation of iodine status in the general population. However, it has failed to assure adequate iodine nutrition during pregnancy and lactation.
Collapse
|
21
|
Nazeri P, Shab-Bidar S, Pearce EN, Shariat M. Thyroglobulin Concentration and Maternal Iodine Status During Pregnancy: A Systematic Review and Meta-Analysis. Thyroid 2020; 30:767-779. [PMID: 31910106 DOI: 10.1089/thy.2019.0712] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Background: Literature to date has been inconclusive regarding the value of thyroglobulin (Tg) as a marker of iodine status in pregnant women. This systematic review and meta-analysis is one of the first to assess whether Tg concentration accurately reflects iodine status among pregnant women. Methods: We searched MEDLINE, the Web of Science, the Cochrane Library, Scopus, and other relevant databases to identify relevant studies published in the English language, between January 1988 and December 2018. The criteria for study inclusion in the systematic review were human studies, healthy pregnant women as participants, and available data for maternal urinary iodine concentration (UIC) and Tg level. Each study was assessed for quality and risk of bias. The pooled mean Tg values, and 95% confidence intervals were estimated in a population of women with UIC <150 and UIC ≥150 μg/L during pregnancy. Potential linear or nonlinear dose-response associations between maternal UIC and Tg concentration were examined. Results: Of 814 identified studies, 25 were eligible for inclusion in the meta-analysis. Studies included were conducted in Africa, Asia, Europe, South America, and the Oceania. The pooled mean (95% confidence interval [CI]) Tg concentration in iodine-deficient pregnant women was higher than that in iodine-sufficient pregnant women (10.73 μg/L [5.65-15.82] vs. 7.34 μg/L [2.20-12.47]); a comparison of the 95% CI showed that none of these values was significantly different. No significant differences were observed in Tg concentration between the two groups in each trimester of pregnancy. Dose-response meta-analyses revealed a significant nonlinear association between maternal UIC and Tg concentration during pregnancy. Among populations of pregnant women, an inverse association was found between UIC values <100 μg/L and Tg concentration (p-linearity = 0.007; p-nonlinearity = 0.027); however, higher values of UIC were not associated with Tg concentration. Conclusions: Our meta-analysis showed that Tg concentration can be a sensitive indicator of iodine deficiency, specifically in populations of pregnant women with median UIC <100 μg/L. Further studies are warranted to determine the sensitivity of Tg at different degrees of iodine deficiency during pregnancy.
Collapse
Affiliation(s)
- Pantea Nazeri
- Family Health Institute, Breastfeeding Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Sakineh Shab-Bidar
- Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran
| | - Elizabeth N Pearce
- Section of Endocrinology, Diabetes and Nutrition, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Mamak Shariat
- Family Health Institute, Maternal, Fetal and Neonatal Research Center, Tehran University of Medical Sciences, Tehran, Iran
| |
Collapse
|
22
|
Lazarus JH. Iodine deficiency in Israeli pregnant women - a time for action. Isr J Health Policy Res 2020; 9:20. [PMID: 32357947 PMCID: PMC7193697 DOI: 10.1186/s13584-020-00382-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 04/24/2020] [Indexed: 11/10/2022] Open
Abstract
Iodine is an essential micronutrient for thyroid gland function. Iodine deficiency disorders are a spectrum of conditions affecting the fetus, child, adolescent and adult. Iodine requirements are increased in pregnancy in order that the fetus receives enough maternal thyroxine via transplacental passage. Previous studies in Israel have shown widespread iodine deficiency by measurement of urinary iodine concentrations in school age children and adults. The present study clearly shows iodine deficiency in a group of 2nd trimester women as judged by measurement of serum thyroglobulin (a recently evaluated marker of iodine deficiency). An additional factor in this work is that the subjects all resided in an area using desalinated water. Desalination has previously been shown to significantly reduce the iodine content of water compared to water in Israel not subject to this process.The data in this group of pregnant women should serve as a wakeup call to the public health community to correct this deficiency which is known to significantly affect child neurodevelopment. There are several issues to be addressed. The knowledge base relating to iodine nutrition especially during pregnancy is low. An educational plan is required. The strategy for achieving adequate iodine nutrition in the population and particularly before and during pregnancy requires urgent review. While iodine supplementation before and during gestation can correct iodine deficiency, the provision of iodised salt in the community is recommended, similar to more than 80% of countries in the world.It is indeed a time for action to ensure the adequate intellectual performance of Israel's children.
Collapse
Affiliation(s)
- John H Lazarus
- Clinical Endocrinology, Thyroid Research Group, School of Medicine, Cardiff University, Cardiff, UK. .,Regional Coordinator West and Central Europe, Iodine Global Network, Cardiff, UK.
| |
Collapse
|
23
|
Akdader-Oudahmane S, Hamouli-Saïd Z, Zimmermann MB, Kherrab H, Azzoug S, Meskine D. High prevalence of TPO-Abs and subclinical hypothyroidism in iodine-sufficient pregnant women in Northern Algeria. J Trace Elem Med Biol 2020; 61:126533. [PMID: 32417633 DOI: 10.1016/j.jtemb.2020.126533] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 01/22/2020] [Accepted: 04/06/2020] [Indexed: 10/24/2022]
Abstract
BACKGROUND Iodine is a trace element whose adequate intakes are essential during gestation to promote the correct growth and development of the fetus. Historically, endemic goiter and cretinism affected northern regions of Algeria, and iodized salt was introduced in 1990. However, there has been no national study of iodine nutrition in Algeria since 1994. The aim of this study was to assess the iodine status and thyroid function of women of reproductive age (WRA) and pregnant women (PW) in northern Algeria. METHODS Healthy WRA and PW were recruited from an urban area (Algiers) and healthy WRA from a rural area (Tizi-Ouzou). Spot urine and venous blood samples were collected to assess iodine status (urinary iodine concentration, UIC) and serum thyroid hormones (TSH, FT4), thyroglobulin (Tg), and anti-thyroid peroxidase antibodies (TPO-Ab) concentrations. RESULTS The median UIC in WRA was 256 μg/L (IQR: 166-354 μg/L; n = 151) in Algiers and 253 μg/L (167-341 μg/L; n = 150) in Tizi-Ouzou. The median UIC for the PW in Algiers was 233 μg/L (IQR: 157-326 μg/L; n = 173).Thirty-five percent of WRA and 30% of PW had an UIC > 300 μg/L. Median TSH, FT4 and Tg concentrations were within reference ranges in all groups of women. Among PW, 72.7%, 75.4% and 75.5% in the first, second and third trimester were TPO-Ab+. Among TPO-Ab + PW in the first, second and third trimesters, 18.7%, 13% and 10.3% had subclinical hypothyroidism. CONCLUSION In northern Algeria, median UICs in PW indicate iodine sufficiency, and in WRA indicate more than adequate intakes. About 75% of PW are TPO-Ab + and the prevalence of subclinical hypothyroidism is high. Monitoring and surveillance of iodine fortification programs is vital to avoid both iodine deficiency and excess. There is an urgent need for a comprehensive national iodine status survey including school-age children and other vulnerable population groups in Algeria.
Collapse
Affiliation(s)
- Samira Akdader-Oudahmane
- L.B.P.O/Section Endocrinology, Faculty of Biological Sciences, USTHB, BP 32 El-Alia, Bab Ezzouar, 16 111 Algiers, Algeria; Departement of Biology, Faculty of Biological Sciences and Agricultural Sciences, UMMTO, 15 000 Tizi-Ouzou, Algeria.
| | - Zohra Hamouli-Saïd
- L.B.P.O/Section Endocrinology, Faculty of Biological Sciences, USTHB, BP 32 El-Alia, Bab Ezzouar, 16 111 Algiers, Algeria
| | | | - Hanane Kherrab
- Endocrinology Department, Public Hospital Etablishment IbnZiri, Bologhine, 16090 Algiers, Algeria
| | - Said Azzoug
- Endocrinology Department, Public Hospital Etablishment IbnZiri, Bologhine, 16090 Algiers, Algeria
| | - Djamila Meskine
- Endocrinology Department, Public Hospital Etablishment IbnZiri, Bologhine, 16090 Algiers, Algeria
| |
Collapse
|
24
|
Ollero MD, Martínez JP, Pineda J, Toni M, Espada M, Anda E. Change over time in the iodine nutritional status of pregnant women from the Pamplona healthcare region. ACTA ACUST UNITED AC 2020; 67:643-649. [PMID: 32327369 DOI: 10.1016/j.endinu.2019.12.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Revised: 11/30/2019] [Accepted: 12/11/2019] [Indexed: 11/18/2022]
Abstract
INTRODUCTION Adequate iodine intake is essential during pregnancy. A previous study of pregnant women from the Pamplona healthcare region showed mild iodine deficiency (mean urinary iodine level, 125 mcg/L). This study was intended to ascertain the iodine intake of pregnant women in our region and to analyze the change over time in their iodine nutritional status. METHODS An observational study of 400 women in their first trimester of pregnancy. An iodine intake questionnaire was administered. To assess iodine status, urinary iodine concentration (UIC) was measured in a simple urine sample, and serum thyroglobulin levels were determined. In addition, thyroid volume was measured by cervical ultrasound examination. RESULTS Iodized salt was used by 70.5% of all participants (55.3% since the pre-gestational period) and 98.5% of them received iodine-containing supplements (mean dose, 202.6±30.1 mcg/day). Mean urinary iodine concentration was 242 mcg/L (138.5-415.5 mcg/L) and the mean serum thyroglobulin level was 12.3 mcg/L (8.3-9 mcg/L). Iodized salt intake was associated with higher UICs and lower thyroid volume. No differences were found in any of the tested parameters regarding the intake of dairy products, fish, or eggs. CONCLUSIONS Iodine intake by pregnant women in Pamplona has increased due to a greater use of iodized salt and to higher doses of iodine supplements. As a result of this, an adequate iodine status has been achieved in the last decade.
Collapse
Affiliation(s)
- M Dolores Ollero
- Servicio de Endocrinología y Nutrición, Complejo Hospitalario de Navarra, Pamplona (Navarra), España; Instituto de Investigación Sanitaria de Navarra (IdisNa), Pamplona (Navarra), España.
| | - Juan Pablo Martínez
- Sección de Endocrinología, Hospital García Orcoyen, Estella (Navarra), España
| | - Javier Pineda
- Servicio de Endocrinología y Nutrición, Complejo Hospitalario de Navarra, Pamplona (Navarra), España; Instituto de Investigación Sanitaria de Navarra (IdisNa), Pamplona (Navarra), España
| | - Marta Toni
- Instituto de Investigación Sanitaria de Navarra (IdisNa), Pamplona (Navarra), España; Sección de Endocrinología, Hospital García Orcoyen, Estella (Navarra), España
| | - Mercedes Espada
- Unidad de Química Clínica, Laboratorio de Salud Pública del Gobierno Vasco, Derio, España
| | - Emma Anda
- Servicio de Endocrinología y Nutrición, Complejo Hospitalario de Navarra, Pamplona (Navarra), España; Instituto de Investigación Sanitaria de Navarra (IdisNa), Pamplona (Navarra), España
| |
Collapse
|
25
|
Rosen SR, Ovadia YS, Anteby EY, Fytlovich S, Aharoni D, Zamir D, Gefel D, Shenhav S. Low intake of iodized salt and iodine containing supplements among pregnant women with apparently insufficient iodine status - time to change policy? Isr J Health Policy Res 2020; 9:9. [PMID: 32223752 PMCID: PMC7104484 DOI: 10.1186/s13584-020-00367-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 02/18/2020] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Iodine is an essential nutrient for human health throughout the life cycle, especially during early stages of intrauterine life and infancy, to ensure adequate neurocognitive development. The growing global reliance on desalinated iodine-diluted water raises the specter of increased iodine deficiency in several regions. The case of Israel may be instructive for exploring the link between iodine status and habitual iodine intake in the setting of extensive national reliance on desalinated water. The aim of this study was to explore the relationship between iodine intake, including iodized salt and iodine-containing supplements intake, and iodine status among pregnant women residing in a sub-district of Israel that is highly reliant on desalinated iodine-diluted water. METHODS A total of 134 consecutive pregnant women were recruited on a voluntary basis from the obstetrics department of the Barzilai University Medical Center during 2018. Blood was drawn from participants to determine levels of serum thyrotropin (TSH), thyroid peroxidase antibodies (TPOAb), thyroglobulin antibodies (TgAb) and thyroglobulin (Tg). An iodine food frequency questionnaire (sIFFQ) was used to assess iodine intake from food, IS and ICS. A questionnaire was used to collect data on demographic and health characteristics. RESULTS A total of 105 pregnant women without known or reported thyroid disease were included in the study. Elevated Tg values (≥ 13 μg/L), were found among 67% of participants, indicating insufficient iodine status. The estimated iodine intake (median, mean ± SD 189, 187 ± 106 μg/d by sIFFQ) was lower than the levels recommended by the World Health Organization and the Institute of Medicine (250 vs. 220 μg/day respectively). The prevalence of iodized salt intake and iodine containing supplement intake were 4 and 52% (respectively). Values of Tg > 13 μg/L were inversely associated with compliance with World Health Organization and Institute of Medicine recommendations. CONCLUSIONS While the Israeli Ministry of Health has recommended the intake of iodized salt and iodine containing supplements, this is apparently insufficient for achieving optimal iodine status among Israeli pregnant women. The evidence of highly prevalent probable iodine deficiency in a sample of pregnant women suggests an urgent need for a national policy of iodized salt regulation, as well as guidelines to promote iodine containing supplements and adherence to them by caregivers. In addition, studies similar to this one should be undertaken in additional countries reliant on desalinated iodine-diluted water to further assess the impact of desalinization on maternal iodine status.
Collapse
Affiliation(s)
- Shani R Rosen
- School of Nutritional Science; Institute of Biochemistry, Food Science and Nutrition; Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, 76100, Rehovot, Israel.
- Obstetrics and Gynecology Department, "Barzilai" University Medical Center Ashkelon, Ashkelon, Israel.
| | - Yaniv S Ovadia
- Obstetrics and Gynecology Department, "Barzilai" University Medical Center Ashkelon, Ashkelon, Israel
- Foreign studies department; Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Eyal Y Anteby
- Obstetrics and Gynecology Department, "Barzilai" University Medical Center Ashkelon, Ashkelon, Israel
- Faculty of Health Sciences, Ben-Gurion University of Negev, Ashkelon, Israel
| | - Shlomo Fytlovich
- Laboratory of Clinical Biochemistry, Barzilai University Medical Center Ashkelon, Ashkelon, Israel
| | - Dorit Aharoni
- Laboratory of Clinical Biochemistry, Barzilai University Medical Center Ashkelon, Ashkelon, Israel
| | - Doron Zamir
- Faculty of Health Sciences, Ben-Gurion University of Negev, Ashkelon, Israel
- Internal Medicine Department, Barzilai University Medical Center Ashkelon, Ashkelon, Israel
| | - Dov Gefel
- School of Nutritional Science; Institute of Biochemistry, Food Science and Nutrition; Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, 76100, Rehovot, Israel
| | - Simon Shenhav
- Obstetrics and Gynecology Department, "Barzilai" University Medical Center Ashkelon, Ashkelon, Israel
- Faculty of Health Sciences, Ben-Gurion University of Negev, Ashkelon, Israel
| |
Collapse
|
26
|
Censi S, Watutantrige-Fernando S, Groccia G, Manso J, Plebani M, Faggian D, Mion MM, Venturini R, Andrisani A, Casaro A, Vita P, Avogadro A, Camilot M, Scaroni C, Bertazza L, Barollo S, Mian C. The Effects of Iodine Supplementation in Pregnancy on Iodine Status, Thyroglobulin Levels and Thyroid Function Parameters: Results from a Randomized Controlled Clinical Trial in a Mild-to-Moderate Iodine Deficiency Area. Nutrients 2019; 11:nu11112639. [PMID: 31689890 PMCID: PMC6893432 DOI: 10.3390/nu11112639] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 10/10/2019] [Accepted: 10/23/2019] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Iodine supplementation during pregnancy in areas with mild-to-moderate iodine deficiency is still debated. METHODS A single-center, randomized, single-blind and placebo-controlled (3:2) trial was conducted. We enrolled 90 women before 12 weeks of gestation. From enrollment up until 8 weeks after delivery, 52 women were given an iodine supplement (225 ug/day, potassium iodide tablets) and 38 were given placebo. At recruitment (T0), in the second (T1) and third trimesters (T2), and 8 weeks after delivery (T3), we measured participants' urinary iodine-to-creatinine ratio (UI/Creat), thyroid function parameters (thyroglobulin (Tg), TSH, FT3, and FT4), and thyroid volume (TV). The newborns' urinary iodine concentrations were evaluated in 16 cases. RESULTS Median UI/Creat at recruitment was 53.3 ug/g. UI/Creat was significantly higher in supplemented women at T1 and T2. Tg levels were lower at T1 and T2 in women with UI/Creat ≥ 150 ug/g, and in the Iodine group at T2 (p = 0.02). There was a negative correlation between Tg and UI/Creat throughout the study (p = 0.03, r = -0.1268). A lower TSH level was found in the Iodine group at T3 (p = 0.001). TV increased by +Δ7.43% in the Iodine group, and by +Δ11.17% in the Placebo group. No differences were found between the newborns' TSH levels on screening the two groups. CONCLUSION Tg proved a good parameter for measuring iodine intake in our placebo-controlled series. Iodine supplementation did not prove harmful to pregnancy in areas of mild-to-moderate iodine deficiency, with no appreciable harmful effect on thyroid function.
Collapse
Affiliation(s)
- Simona Censi
- Department of Medicine (DIMED), Endocrinology Unit; University of Padova, 35121 Padova, Italy.
| | | | - Giulia Groccia
- Department of Medicine (DIMED), Endocrinology Unit; University of Padova, 35121 Padova, Italy.
| | - Jacopo Manso
- Department of Medicine (DIMED), Endocrinology Unit; University of Padova, 35121 Padova, Italy.
| | - Mario Plebani
- Laboratory Medicine, Department of Medical and Surgical Sciences, University of Padua, 35121 Padua, Italy.
| | - Diego Faggian
- Laboratory Medicine, Department of Medical and Surgical Sciences, University of Padua, 35121 Padua, Italy.
| | - Monica Maria Mion
- Laboratory Medicine, Department of Medical and Surgical Sciences, University of Padua, 35121 Padua, Italy.
| | - Roberta Venturini
- Laboratory Medicine, Department of Medical and Surgical Sciences, University of Padua, 35121 Padua, Italy.
| | - Alessandra Andrisani
- Department of Women's and Children's Health, University of Padua, Salus Pueri, 35128 Padua, Italy.
| | - Anna Casaro
- Department of Medicine (DIMED), Endocrinology Unit; University of Padova, 35121 Padova, Italy.
| | - Pietro Vita
- Department of Medicine (DIMED), Endocrinology Unit; University of Padova, 35121 Padova, Italy.
| | - Alessandra Avogadro
- Department of Medicine (DIMED), Endocrinology Unit; University of Padova, 35121 Padova, Italy.
| | - Marta Camilot
- Department of Pediatrics, Regional Centre for Newborn Screening, Diagnosis and Treatment of Inherited Metabolic Diseases and Congenital Endocrine Diseases, Azienda Ospedaliera Universitaria Integrata, 37134 Verona, Italy.
| | - Carla Scaroni
- Department of Medicine (DIMED), Endocrinology Unit; University of Padova, 35121 Padova, Italy.
| | - Loris Bertazza
- Department of Medicine (DIMED), Endocrinology Unit; University of Padova, 35121 Padova, Italy.
| | - Susi Barollo
- Department of Medicine (DIMED), Endocrinology Unit; University of Padova, 35121 Padova, Italy.
| | - Caterina Mian
- Department of Medicine (DIMED), Endocrinology Unit; University of Padova, 35121 Padova, Italy.
| |
Collapse
|
27
|
The Joint Role of Thyroid Function and Iodine Status on Risk of Preterm Birth and Small for Gestational Age: A Population-Based Nested Case-Control Study of Finnish Women. Nutrients 2019; 11:nu11112573. [PMID: 31731400 PMCID: PMC6893669 DOI: 10.3390/nu11112573] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 10/21/2019] [Accepted: 10/22/2019] [Indexed: 11/17/2022] Open
Abstract
Normal maternal thyroid function during pregnancy is essential for fetal development and depends upon an adequate supply of iodine. Little is known about how iodine status is associated with preterm birth and small for gestational age (SGA) in mildly iodine insufficient populations. Our objective was to evaluate associations of early pregnancy serum iodine, thyroglobulin (Tg), and thyroid-stimulating hormone (TSH) with odds of preterm birth and SGA in a prospective, population-based, nested case-control study from all births in Finland (2012–2013). Cases of preterm birth (n = 208) and SGA (n = 209) were randomly chosen from among all singleton births. Controls were randomly chosen from among singleton births that were not preterm (n = 242) or SGA (n = 241) infants during the same time period. Women provided blood samples at 10–14 weeks’ gestation for serum iodide, Tg and TSH measurement. We used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for preterm birth and SGA. Each log-unit increase in serum iodide was associated with higher odds of preterm birth (adjusted OR = 1.19, 95% CI = 1.02–1.40), but was not associated with SGA (adjusted OR = 1.01, 95% CI = 0.86–1.18). Tg was not associated with preterm birth (OR per 1 log-unit increase = 0.87, 95% CI = 0.73–1.05), but was inversely associated with SGA (OR per log-unit increase = 0.78, 95% CI = 0.65–0.94). Neither high nor low TSH (versus normal) were associated with either outcome. These findings suggest that among Finnish women, iodine status is not related to SGA, but higher serum iodide may be positively associated with preterm birth.
Collapse
|
28
|
Manousou S, Andersson M, Eggertsen R, Hunziker S, Hulthén L, Nyström HF. Iodine deficiency in pregnant women in Sweden: a national cross-sectional study. Eur J Nutr 2019; 59:2535-2545. [PMID: 31616973 PMCID: PMC7413865 DOI: 10.1007/s00394-019-02102-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 09/26/2019] [Indexed: 01/20/2023]
Abstract
Purpose Voluntary salt iodization at 50 mg/kg salt ensures adequate iodine nutrition in Swedish school-aged children, but iodine status in pregnant women is uncertain. Methods We conducted a cross-sectional national study of 743 pregnant women, at median gestational age of 23 weeks (IQR 9, 38), recruited from maternal health care centers. We measured: urinary iodine concentration (UIC) and urinary creatinine concentration in spot urine samples; thyroglobulin (Tg), thyroid-stimulating hormone (TSH), and total thyroxine (tT4) on dried blood spots (DBS); and thyreoperoxidase antibodies in serum samples. Data on dietary supplement use were obtained, and women were classified as supplement users (consuming multivitamins containing ≥ 150 µg iodine/day) and non-supplement users (no supplements or < 150 µg iodine/day from supplements). Results Overall median UIC [bootstrapped 95% confidence interval (CI)] was 101 µg/L (95, 108; n = 737): 149 µg/L (132, 164) in supplement users (n = 253) and 85 µg/L (79, 92) in non-supplement users (n = 440) (p < 0.001). Overall geometric mean DBS-Tg (95% CI) was 22.1 μg/L (20.8, 23.5; n = 675) and the prevalence of elevated DBS-Tg was 19%. DBS-Tg was lower in supplement users (n = 229) than in non-supplement users (n = 405) (19.1 vs 24.4 μg/L, p < 0.001). DBS-TSH, DBS-tT4, and S-TPOab positivity did not differ between the two groups. Conclusions Pregnant women in Sweden have inadequate iodine nutrition. Women not taking iodine supplements containing ≥ 150 µg iodine/day are affected by mild iodine deficiency and are at higher risk for increased thyroid activity, while maintaining euthyroidism. Iodine intake should be improved in women both before and after conception by promotion of iodized salt instead of non-iodized salt. We urge regular monitoring of iodine status in the general Swedish population, as well as in risk groups.
Collapse
Affiliation(s)
- Sofia Manousou
- Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden. .,Frölunda Specialist Hospital, Marconigatan 31, 42144, Västra Frölunda, Sweden.
| | - Maria Andersson
- Division of Gastroenterology and Nutrition, University Children's Hospital Zurich, Eleonore Foundation, Steinwiesstrasse 75, 8032, Zurich, Switzerland.,Iodine Global Network, Ottawa, ON, Canada
| | - Robert Eggertsen
- Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden.,Mölnlycke Health Care Centre, Ekdalavägen 2, 43530, Mölnlycke, Sweden
| | - Sandra Hunziker
- Human Nutrition Laboratory, Institute of Food Nutrition and Health, ETH Zurich, Schmelzbergstrasse 7, 8092, Zurich, Switzerland
| | - Lena Hulthén
- Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden.,Department of Internal Medicine and Clinical Nutrition, Sahlgrenska Academy, University of Gothenburg, Medicinaregatan 13, 40530, Gothenburg, Sweden
| | - Helena Filipsson Nyström
- Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden.,Department of Endocrinology, Sahlgrenska University Hospital, Gröna Stråket 8, 41345, Gothenburg, Sweden
| |
Collapse
|
29
|
Excessive iodine intake is associated with formation of thyroid nodules in pregnant Chinese women. Nutr Res 2019; 66:61-67. [DOI: 10.1016/j.nutres.2019.02.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 01/04/2019] [Accepted: 02/27/2019] [Indexed: 02/08/2023]
|
30
|
Farebrother J, Zimmermann MB, Andersson M. Excess iodine intake: sources, assessment, and effects on thyroid function. Ann N Y Acad Sci 2019; 1446:44-65. [PMID: 30891786 DOI: 10.1111/nyas.14041] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 01/30/2019] [Accepted: 02/02/2019] [Indexed: 12/15/2022]
Abstract
Iodine is essential for thyroid hormone synthesis. High iodine intakes are well tolerated by most healthy individuals, but in some people, excess iodine intakes may precipitate hyperthyroidism, hypothyroidism, goiter, and/or thyroid autoimmunity. Individuals with preexisting thyroid disease or those previously exposed to iodine deficiency may be more susceptible to thyroid disorders due to an increase in iodine intake, in some cases at intakes only slightly above physiological needs. Thyroid dysfunction due to excess iodine intake is usually mild and transient, but iodine-induced hyperthyroidism can be life-threatening in some individuals. At the population level, excess iodine intakes may arise from consumption of overiodized salt, drinking water, animal milk rich in iodine, certain seaweeds, iodine-containing dietary supplements, and from a combination of these sources. The median urinary iodine concentration (UIC) of a population reflects the total iodine intake from all sources and can accurately identify populations with excessive iodine intakes. Our review describes the association between excess iodine intake and thyroid function. We outline potential sources of excess iodine intake and the physiological responses and consequences of excess iodine intakes. We provide guidance on choice of biomarkers to assess iodine intake, with an emphasis on the UIC and thyroglobulin.
Collapse
Affiliation(s)
- Jessica Farebrother
- Human Nutrition Laboratory, Institute of Food, Nutrition, and Health, ETH Zurich, Zurich, Switzerland.,Department of Women and Children's Health, King's College London, London, UK
| | - Michael B Zimmermann
- Human Nutrition Laboratory, Institute of Food, Nutrition, and Health, ETH Zurich, Zurich, Switzerland.,Iodine Global Network, Ottawa, Ontario, Canada
| | - Maria Andersson
- Human Nutrition Laboratory, Institute of Food, Nutrition, and Health, ETH Zurich, Zurich, Switzerland.,Iodine Global Network, Ottawa, Ontario, Canada.,Division of Gastroenterology and Nutrition, University Children's Hospital Zurich, Zurich, Switzerland
| |
Collapse
|
31
|
Effectiveness of increased salt iodine concentration on iodine status: trend analysis of cross-sectional national studies in Switzerland. Eur J Nutr 2019; 59:581-593. [PMID: 30843107 DOI: 10.1007/s00394-019-01927-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 02/06/2019] [Indexed: 01/26/2023]
Abstract
PURPOSE Despite longstanding voluntary salt iodisation in Switzerland, data suggest inadequate iodine intake in vulnerable population groups. In response, the salt iodine concentration was increased from 20 to 25 mg/kg and we assessed the impact on iodine status. METHODS We conducted a cross-sectional national study in school-age children (n = 731), women of reproductive age (n = 353) and pregnant women (n = 363). We measured urinary iodine concentration (UIC) and urinary sodium concentration (UNaC) in spot urine samples. The current median UIC was compared with national data from 1999, 2004 and 2009. We measured TSH, total T4 and thyroglobulin (Tg) on dried blood spot samples collected in women. RESULTS The median UIC (bootstrapped 95% CI) was 137 µg/L (131, 143 µg/L) in school children, 88 µg/L (72, 103 µg/L) in women of reproductive age and 140 µg/L (124, 159 µg/L) in pregnant women. Compared to 2009, the median UIC increased modestly in school children (P < 0.001), but did not significantly change in pregnant women (P = 0.417). Estimated sodium intake exceeded the recommendations in all population groups. The prevalence of thyroid disorders in women was low, but Tg was elevated in 13% of the pregnant women. CONCLUSION Iodine intake is overall adequate in Swiss school-age children, but only borderline sufficient in pregnant and non-pregnant women, despite high salt intakes and satisfactory household coverage with iodized salt. Our findings suggest increasing the concentration of iodine in salt may not improve iodine intakes in women if iodised salt is not widely used in processed foods. REGISTRATION This trial was registered at clinicaltrials.gov as NCT02312466.
Collapse
|
32
|
Zhao W, Li X, Xia X, Gao Z, Han C. Iodine Nutrition During Pregnancy: Past, Present, and Future. Biol Trace Elem Res 2019; 188:196-207. [PMID: 30218312 DOI: 10.1007/s12011-018-1502-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Accepted: 08/30/2018] [Indexed: 12/22/2022]
Abstract
Iodine is a trace element that is important for the synthesis of thyroid hormones. During pregnancy, iodine requirements are increased by approximately 50% because of physiological changes. Adequate iodine status in pregnancy is crucial for maternal health and fetal growth. The World Health Organization (WHO) recommends a daily intake of 250 μg iodine for pregnant women to maintain adequate iodine status. Severe iodine deficiency during pregnancy can result in a series of detrimental effects on maternal and fetal health including hypothyroidism, goiter, stillbirth, abortion, increased neonatal mortality, neurological damage, and intellectual impairment. Correction of severe iodine deficiency can reduce the risk of adverse impacts. However, the influences of mild-to-moderate maternal iodine deficiency on fetal neural development and cognitive function are less clear. The safety and efficacy of iodine supplementation in mildly-to-moderately iodine-deficient women also remain uncertain. In addition, excess iodine during pregnancy carries a risk of adverse effects, and the recommended safe upper limits of iodine intake are controversial. Effective iodine supplementation should be implemented, and routine monitoring is necessary to guarantee adequate iodine status.
Collapse
Affiliation(s)
- Wei Zhao
- Department of Endocrinology, Dalian Municipal Central Hospital Affiliated of Dalian Medical University, No. 826 Xinan Street, Dalian, 116033, Liaoning Province, People's Republic of China
| | - Xinyu Li
- Department of Endocrinology, Dalian Municipal Central Hospital Affiliated of Dalian Medical University, No. 826 Xinan Street, Dalian, 116033, Liaoning Province, People's Republic of China
| | - Xinghai Xia
- Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, 500 University Dr, Hershey, PA, 17033, USA
| | - Zhengnan Gao
- Department of Endocrinology, Dalian Municipal Central Hospital Affiliated of Dalian Medical University, No. 826 Xinan Street, Dalian, 116033, Liaoning Province, People's Republic of China.
| | - Cheng Han
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Forchheimer 216, the Bronx, New York, NY, 10461, USA.
| |
Collapse
|
33
|
Bell GA, Männistö T, Liu A, Kannan K, Yeung EH, Kim UJ, Suvanto E, Surcel HM, Gissler M, Mills JL. The joint role of thyroid function and iodine concentration on gestational diabetes risk in a population-based study. Acta Obstet Gynecol Scand 2019; 98:500-506. [PMID: 30580457 DOI: 10.1111/aogs.13523] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 12/11/2018] [Indexed: 01/04/2023]
Abstract
INTRODUCTION Iodine is essential for thyroid function, and iodine deficiency during pregnancy is common in Europe and the USA. However, no published studies have examined the role of iodine deficiency in the relation between thyroid function and gestational diabetes mellitus (GDM). MATERIAL AND METHODS We conducted a population-based, nested case-control study within the Finnish Maternity Cohort using pregnancy and perinatal outcome data from the Finnish Maternal Birth Register. We randomly selected 224 GDM cases with singleton pregnancies and 224 controls without GDM from all singleton births occurring in Finland during 2012-2013. Blood was drawn at 10-14 weeks' gestation and analyzed for serum iodide, thyroglobulin, and thyroid-stimulating hormone (TSH) concentrations. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CI) of GDM. RESULTS Very high thyroglobulin concentration (>95% percentile; >83 μg/L) was not associated with significantly altered odds of GDM compared to those with normal levels (OR 0.41; 95% CI: 0.12, 1.38). High concentrations of TSH were also not associated with increased odds of GDM compared to normal levels of TSH (OR 0.45; 95% CI: 0.06, 3.18). Women in the lowest 5th percentile (<1.58 ng/mL) of iodine did not have increased odds of GDM compared to those with iodide in the highest quartile (OR 0.39; 95% CI: 0.11, 1.35). CONCLUSIONS Low levels of iodide and thyroid function in early pregnancy are not associated with increased risk of GDM in this mildly iodine-deficient population.
Collapse
Affiliation(s)
- Griffith A Bell
- Division of Intramural Population Health Research, National Institutes of Health, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD, USA
| | - Tuija Männistö
- Northern Finland Laboratory Center NordLab, Oulu University and Oulu University Hospital, Oulu, Finland
| | - Aiyi Liu
- Division of Intramural Population Health Research, National Institutes of Health, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD, USA
| | | | - Edwina H Yeung
- Division of Intramural Population Health Research, National Institutes of Health, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD, USA
| | - Un-Jung Kim
- Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Eila Suvanto
- Northern Finland Laboratory Center NordLab, Oulu University and Oulu University Hospital, Oulu, Finland
| | - Heljä-Marja Surcel
- Biobank Borealis of Northern Finland, Oulu University Hospital, Oulu, Finland.,Faculty of Medicine, University of Oulu, Oulu, Finland
| | - Mika Gissler
- National Institute of Health and Welfare, Helsinki, Finland.,Karolinska Institute, Stockholm, Sweden
| | - James L Mills
- Division of Intramural Population Health Research, National Institutes of Health, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD, USA
| |
Collapse
|
34
|
Farebrother J, Zimmermann MB, Assey V, Castro MC, Cherkaoui M, Fingerhut R, Jia Q, Jukic T, Makokha A, San Luis TO, Wegmüller R, Andersson M. Thyroglobulin Is Markedly Elevated in 6- to 24-Month-Old Infants at Both Low and High Iodine Intakes and Suggests a Narrow Optimal Iodine Intake Range. Thyroid 2019; 29:268-277. [PMID: 30648484 DOI: 10.1089/thy.2018.0321] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
BACKGROUND In areas with incomplete salt iodization coverage, infants and children aged 6-24 months weaning from breast milk and receiving complementary foods are at risk of iodine deficiency. However, few data exist on the risk of excessive iodine intake in this age group. Thyroglobulin (Tg) is a sensitive marker of iodine intake in school-age children and adults and may be used to estimate the optimal iodine intake range in infancy. The aim of this study was to assess the association of low and high iodine intakes with Tg and thyroid function in weaning infants. METHODS This multicenter cross-sectional study recruited infants aged 6-24 months (n = 1543; Mage = 12.2 ± 4.6 months) receiving breast milk with complementary foods, from seven countries in areas with previously documented deficient, sufficient, or excessive iodine intake in schoolchildren or pregnant women. Urinary iodine concentration (UIC) and Tg, total thyroxine, and thyrotropin were measured using dried blood spot testing. RESULTS Median UIC ranged from 48 μg/L (interquartile range 31-79 μg/L) to 552 μg/L (interquartile range 272-987 μg/L) across the study sites. Median Tg using dried blood spot testing was high (>50 μg/L) at estimated habitual iodine intakes <50 μg/day and >230 μg/day. Prevalence of overt thyroid disorders was low (<3%). Yet, subclinical hyperthyroidism was observed in the countries with the lowest iodine intake. CONCLUSIONS Tg is a sensitive biomarker of iodine intake in 6- to 24-month-old infants and follows a U-shaped relationship with iodine intake, suggesting a relatively narrow optimal intake range. Infants with low iodine intake may be at increased risk of subclinical thyroid dysfunction. In population monitoring of iodine deficiency or excess, assessment of iodine status using UIC and Tg may be valuable in this young age group.
Collapse
Affiliation(s)
- Jessica Farebrother
- 1 Human Nutrition Laboratory, Institute of Food, Nutrition and Health, ETH Zurich, Switzerland
| | - Michael B Zimmermann
- 1 Human Nutrition Laboratory, Institute of Food, Nutrition and Health, ETH Zurich, Switzerland
- 2 Iodine Global Network, Ottawa, Ottawa, Canada
| | - Vincent Assey
- 2 Iodine Global Network, Ottawa, Ottawa, Canada
- 3 Nutrition Services Section, Preventive Services Department; Ministry of Health, Community Development, Gender, Elderly, and Children, Dar es Salaam, Tanzania
| | | | - Mohamed Cherkaoui
- 5 Faculté des Sciences Semlalia, Université Caddi Ayyed, Marrakech, Morocco
| | - Ralph Fingerhut
- 6 Swiss Newborn Screening Laboratory and Children's Research Center; University Children's Hospital Zurich, Zurich, Switzerland
| | - Qingzhen Jia
- 7 Shanxi Institute for Prevention and Treatment of Endemic Disease, Linfen, P.R. China
| | - Tomislav Jukic
- 8 Department of Nuclear Medicine and Oncology, Sestre Milosrdnice University Hospital Center and School of Medicine, University of Zagreb, Zagreb, Croatia
- 9 Faculty of Medicine Osijek, University Josip Juraj Strossmayer Osijek, Osijek, Croatia
| | - Anselimo Makokha
- 10 Department of Food Science, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | - Theofilo O San Luis
- 2 Iodine Global Network, Ottawa, Ottawa, Canada
- 11 St Luke's Medical Center, Quezon City, Manila, The Philippines
| | - Rita Wegmüller
- 12 Medical Research Council The Gambia, Keneba, The Gambia
| | - Maria Andersson
- 1 Human Nutrition Laboratory, Institute of Food, Nutrition and Health, ETH Zurich, Switzerland
- 2 Iodine Global Network, Ottawa, Ottawa, Canada
- 13 Division of Gastroenterology and Nutrition; University Children's Hospital Zurich, Zurich, Switzerland
| |
Collapse
|
35
|
Brindle E, Lillis L, Barney R, Bansil P, Lyman C, Boyle DS. Measurement of micronutrient deficiency associated biomarkers in dried blood spots using a multiplexed immunoarray. PLoS One 2019; 14:e0210212. [PMID: 30620768 PMCID: PMC6324783 DOI: 10.1371/journal.pone.0210212] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 12/17/2018] [Indexed: 11/18/2022] Open
Abstract
Simplifying blood collection is often critical when collecting specimens in remote and/or austere settings. The use of dried blood spots (DBS) offers a practical collection method suitable for a wide variety of analytes. A small volume of whole blood can be obtained rapidly through a minimally invasive heel- or finger-stick using a disposable safety lancet. Once dried, the samples require no further processing, are stable for months or longer, pose minimal risk of disease transmission, and are easy to ship. DBS are often used in demographic health surveys to assess infectious disease status in vulnerable populations. These samples can be used to screen biomarkers of micronutrient deficiency (MND) and inflammation. We recently described a multiplexed immunoarray, the Q-plex human micronutrient array, which can simultaneously quantify seven biomarkers related to MND, inflammation and malarial antigenemia using plasma (alpha-1-acid glycoprotein, C-reactive protein, ferritin, histidine-rich protein 2, retinol binding protein, soluble transferrin receptor, and thyroglobulin). In this work, we present a protocol for preparing eluates from DBS samples and their measurement using a modified protocol for this new tool. We evaluated the concordance of analyte concentrations (excluding ferritin) from a panel ninety samples of DBS prepared from anticoagulated venous blood and paired K2-EDTA plasma. The results show high correlation between DBS eluates and wet plasma for five of the six analytes screened, suggesting the Q-plex human micronutrient array can be used with DBS samples, but also highlighting that anticoagulants can have a negative effects on some test components.
Collapse
Affiliation(s)
- Eleanor Brindle
- Center for Studies in Demography and Ecology, University of Washington, Seattle, Washington, United States of America
| | | | | | - Pooja Bansil
- PATH, Seattle, Washington, United States of America
| | | | - David S. Boyle
- PATH, Seattle, Washington, United States of America
- * E-mail:
| |
Collapse
|
36
|
Garcia‐Casal MN, Mowson R, Rogers L, Grajeda R. Risk of excessive intake of vitamins and minerals delivered through public health interventions: objectives, results, conclusions of the meeting, and the way forward. Ann N Y Acad Sci 2018; 1446:5-20. [DOI: 10.1111/nyas.13975] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 09/03/2018] [Accepted: 09/08/2018] [Indexed: 11/25/2022]
Affiliation(s)
- Maria Nieves Garcia‐Casal
- Evidence and Programme Guidance Unit, Department of Nutrition for Health and Development World Health Organization Geneva Switzerland
| | - Robin Mowson
- Nutrition and Social Determinants the Pan American Health Organization Washington DC
| | - Lisa Rogers
- Evidence and Programme Guidance Unit, Department of Nutrition for Health and Development World Health Organization Geneva Switzerland
| | - Ruben Grajeda
- Nutrition and Social Determinants the Pan American Health Organization Washington DC
| | | |
Collapse
|
37
|
Pearce EN. Iodine nutrition: recent research and unanswered questions. Eur J Clin Nutr 2018; 72:1226-1228. [PMID: 30185854 DOI: 10.1038/s41430-018-0226-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 05/22/2018] [Indexed: 11/09/2022]
Affiliation(s)
- Elizabeth N Pearce
- Section of Endocrinology, Diabetes, and Nutrition, Boston University School of Medicine, 720 Harrison Ave, Suite 8100, Boston, MA, 02118, USA.
| |
Collapse
|
38
|
Farebrother J, Zimmermann MB, Abdallah F, Assey V, Fingerhut R, Gichohi-Wainaina WN, Hussein I, Makokha A, Sagno K, Untoro J, Watts M, Andersson M. Effect of Excess Iodine Intake from Iodized Salt and/or Groundwater Iodine on Thyroid Function in Nonpregnant and Pregnant Women, Infants, and Children: A Multicenter Study in East Africa. Thyroid 2018; 28:1198-1210. [PMID: 30019625 DOI: 10.1089/thy.2018.0234] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Acute excess iodine intake can damage the thyroid, but the effects of chronic excess iodine intake are uncertain. Few data exist for pregnant and lactating women and infants exposed to excessive iodine intake. METHODS This was a multicenter cross-sectional study. At study sites in rural Kenya and urban Tanzania previously reporting iodine excess in children, urinary iodine concentration (UIC), thyrotropin, total thyroxine, and thyroglobulin (Tg) were measured in school-age children (SAC), women of reproductive age, pregnant (PW) and lactating women, and breast-feeding and weaning infants. In a national study in Djibouti, UIC was measured in SAC and PW. At all sites, daily iodine intake was estimated based on UIC, and iodine concentration was measured in household salt and drinking water. RESULTS The total sample size was 4636: 1390, 2048, and 1198 subjects from Kenya, Tanzania, and Djibouti, respectively. In Kenya and Tanzania: (i) median UIC was well above thresholds for adequate iodine nutrition in all groups and exceeded the threshold for excess iodine intake in SAC; (ii) iodine concentrations >40 mg of iodine/kg were found in approximately 55% of household salt samples; (iii) iodine concentrations ≥10 μg/L were detected in 9% of drinking water samples; (iv) Tg was elevated in all population groups, but the prevalence of thyroid disorders was negligible, except that 5-12% of women of reproductive age had subclinical hyperthyroidism and 10-15% of PW were hypothyroxinemic. In Djibouti: (i) the median UIC was 335 μg/L (interquartile range [IQR] = 216-493 μg/L) in SAC and 265 μg/L (IQR = 168-449 μg/L) in PW; (ii) only 1.6% of Djibouti salt samples (n = 1200) were adequately iodized (>15 mg/kg); (iii) the median iodine concentration in drinking water was 92 μg/L (IQR = 37-158 μg/L; n = 77). In all countries, UIC was not significantly correlated with salt or water iodine concentrations. CONCLUSIONS Although iodine intake was excessive and Tg concentrations were elevated, there was little impact on thyroid function. Chronic excess iodine intake thus appears to be well tolerated by women, infants, and children. However, such high iodine intake is unnecessary and should be avoided. Careful evaluation of contributions from both iodized salt and groundwater iodine is recommended before any review of iodization policy is considered.
Collapse
Affiliation(s)
- Jessica Farebrother
- 1 Human Nutrition Laboratory, Institute of Food, Nutrition, and Health , ETH Zurich, Zurich, Switzerland
| | - Michael B Zimmermann
- 1 Human Nutrition Laboratory, Institute of Food, Nutrition, and Health , ETH Zurich, Zurich, Switzerland
- 2 Iodine Global Network , Ottawa, Canada
| | - Fatma Abdallah
- 3 Tanzania Food and Nutrition Centre , Dar es Salaam, Tanzania
| | - Vincent Assey
- 4 Nutrition Services Section, Preventive Services Department, Ministry of Health , Community Development, Gender, Elderly, and Children, Dar es Salaam, Tanzania
- 5 Regional Coordinator East and Southern Africa, Iodine Global Network , Ottawa, Canada
| | - Ralph Fingerhut
- 6 University Children's Hospital Zurich , Swiss Newborn Screening Laboratory and Children's Research Center, Zurich, Switzerland
| | - Wanjiku N Gichohi-Wainaina
- 7 International Crops Research Institute for Semi-Arid Tropics (ICRISAT) , Lilongwe, Malawi
- 8 Department of Food Science, Jomo Kenyatta University of Agriculture and Technology , Nairobi, Kenya
| | - Izzeldin Hussein
- 9 Regional Coordinator Middle East and North Africa, Iodine Global Network , Ottawa, Canada
| | - Anselimo Makokha
- 8 Department of Food Science, Jomo Kenyatta University of Agriculture and Technology , Nairobi, Kenya
| | - Kalil Sagno
- 10 Djibouti Country Office, United Nations Children's Fund , Djibouti, Djibouti
| | - Juliawati Untoro
- 11 Eastern and Southern Africa Regional Office, United Nations Children's Fund , Nairobi, Kenya
| | - Michael Watts
- 12 Inorganic Geochemistry, Centre for Environmental Geochemistry, British Geological Survey , Nottingham, United Kingdom
| | - Maria Andersson
- 1 Human Nutrition Laboratory, Institute of Food, Nutrition, and Health , ETH Zurich, Zurich, Switzerland
- 2 Iodine Global Network , Ottawa, Canada
- 13 Division of Gastroenterology and Nutrition, University Children's Hospital Zurich , Zurich, Switzerland
| |
Collapse
|
39
|
Dold S, Zimmermann MB, Jukic T, Kusic Z, Jia Q, Sang Z, Quirino A, San Luis TOL, Fingerhut R, Kupka R, Timmer A, Garrett GS, Andersson M. Universal Salt Iodization Provides Sufficient Dietary Iodine to Achieve Adequate Iodine Nutrition during the First 1000 Days: A Cross-Sectional Multicenter Study. J Nutr 2018; 148:587-598. [PMID: 29659964 DOI: 10.1093/jn/nxy015] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 01/16/2018] [Indexed: 12/14/2022] Open
Abstract
Background Dietary iodine requirements are high during pregnancy, lactation, and infancy, making women and infants vulnerable to iodine deficiency. Universal salt iodization (USI) has been remarkably successful for preventing iodine deficiency in the general population, but it is uncertain if USI provides adequate iodine intakes during the first 1000 d. Objective We set out to assess if USI provides sufficient dietary iodine to meet the iodine requirements and achieve adequate iodine nutrition in all vulnerable population groups. Methods We conducted an international, cross-sectional, multicenter study in 3 study sites with mandatory USI legislation. We enrolled 5860 participants from 6 population groups (school-age children, nonpregnant nonlactating women of reproductive age, pregnant women, lactating women, 0-6-mo-old infants, and 7-24-mo-old infants) and assessed iodine status [urinary iodine concentration (UIC)] and thyroid function in Linfen, China (n = 2408), Tuguegarao, the Philippines (n = 2512), and Zagreb, Croatia (n = 940). We analyzed the iodine concentration in household salt, breast milk, drinking water, and cow's milk. Results The salt iodine concentration was low (<15 mg/kg) in 2.7%, 33.6%, and 3.1%, adequate (15-40 mg/kg) in 96.3%, 48.4%, and 96.4%, and high (>40 mg/kg) in 1.0%, 18.0%, and 0.5% of household salt samples in Linfen (n = 402), Tuguegarao (n = 1003), and Zagreb (n = 195), respectively. The median UIC showed adequate iodine nutrition in all population groups, except for excessive iodine intake in school-age children in the Philippines and borderline low intake in pregnant women in Croatia. Conclusions Salt iodization at ∼25 mg/kg that covers a high proportion of the total amount of salt consumed supplies sufficient dietary iodine to ensure adequate iodine nutrition in all population groups, although intakes may be borderline low during pregnancy. Large variations in salt iodine concentrations increase the risk for both low and high iodine intakes. Strict monitoring of the national salt iodization program is therefore essential for optimal iodine nutrition. This trial was registered at clinicaltrials.gov as NCT02196337.
Collapse
Affiliation(s)
- Susanne Dold
- Human Nutrition Laboratory, Institute of Food Nutrition and Health, ETH Zurich, Zurich, Switzerland
| | - Michael B Zimmermann
- Human Nutrition Laboratory, Institute of Food Nutrition and Health, ETH Zurich, Zurich, Switzerland.,Iodine Global Network, Ottawa, Ontario, Canada
| | - Tomislav Jukic
- Department of Nuclear Medicine and Oncology, Sestre Milosrdnice University Hospital Centre and School of Medicine, University of Zagreb, Zagreb, Croatia.,Faculty of Medicine Osijek, University Josip Juraj Strossmayer Osijek, Osijek, Croatia
| | - Zvonko Kusic
- Department of Nuclear Medicine and Oncology, Sestre Milosrdnice University Hospital Centre and School of Medicine, University of Zagreb, Zagreb, Croatia.,Croatian Academy of Sciences and Arts, Zagreb, Croatia
| | - Qingzhen Jia
- Shanxi Institute for Prevention and Treatment of Endemic Disease, Linfen, China
| | - Zhongna Sang
- Institute of Endocrinology, Tianjin Medical University, Tianjin, China
| | - Antonio Quirino
- Technological Institute of the Philippines, Manila, Philippines
| | | | - Ralph Fingerhut
- Swiss Newborn Screening Laboratory, Division of Metabolism and Children's Research Centre (CRC), University Children's Hospital Zurich, Zurich, Switzerland
| | | | - Arnold Timmer
- Global Alliance for Improved Nutrition (GAIN), Geneva, Switzerland
| | - Greg S Garrett
- Global Alliance for Improved Nutrition (GAIN), Geneva, Switzerland
| | - Maria Andersson
- Human Nutrition Laboratory, Institute of Food Nutrition and Health, ETH Zurich, Zurich, Switzerland.,Iodine Global Network, Ottawa, Ontario, Canada
| |
Collapse
|
40
|
Valores de referencia para tiroglobulina sérica en individuos sanos. ENDOCRINOL DIAB NUTR 2018; 65:60-61. [DOI: 10.1016/j.endinu.2017.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 10/05/2017] [Indexed: 11/18/2022]
|
41
|
Gowachirapant S, Jaiswal N, Melse-Boonstra A, Galetti V, Stinca S, Mackenzie I, Thomas S, Thomas T, Winichagoon P, Srinivasan K, Zimmermann MB. Effect of iodine supplementation in pregnant women on child neurodevelopment: a randomised, double-blind, placebo-controlled trial. Lancet Diabetes Endocrinol 2017; 5:853-863. [PMID: 29030199 DOI: 10.1016/s2213-8587(17)30332-7] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2017] [Revised: 07/20/2017] [Accepted: 07/26/2017] [Indexed: 01/06/2023]
Abstract
BACKGROUND Iodine deficiency during pregnancy might be associated with reduced intelligence quotient (IQ) score in offspring. We assessed the effect of iodine supplementation in mildly iodine-deficient pregnant women on neurodevelopment of their offspring in areas where schoolchildren were iodine sufficient. METHODS In this randomised, placebo-controlled trial, pregnant women in Bangalore, India, and Bangkok, Thailand, were randomly assigned (1:1) to receive 200 μg iodine orally once a day or placebo until delivery. Randomisation was done with a computer-generated sequence and stratified by site. Co-primary outcomes were verbal and performance IQ scores on the Wechsler Preschool and Primary Scale of Intelligence Third Edition (WPPSI-III) and the global executive composite score from the Behaviour Rating Inventory of Executive Function-Preschool Version (BRIEF-P) in the children at age 5-6 years. The trial was double-blinded; some unmasking took place at age 2 years for an interim analysis, but participants and nearly all investigators remained masked to group assignment until age 5-6 years. Analysis was by intention to treat using mixed-effects models. This trial is registered with ClinicalTrials.gov, number NCT00791466. FINDINGS Between Nov 18, 2008, and March 12, 2011, 832 women entered the trial at a mean gestational age of 10·7 weeks (SD 2·7); median urinary iodine concentration was 131 μg/L (IQR 81-213). Mean compliance with supplementation was 87%, assessed by monthly tablet counts. 313 children (iodine group, n=159; placebo group, n=154) were analysed for verbal and performance IQ with WPPSI-III and 315 (iodine group, n=159; placebo group, n=156) for overall executive function with BRIEF-P. Mean WPPSI-III scores for verbal IQ were 89·5 (SD 9·8) in the iodine group and 90·2 (9·8) in the placebo group (difference -0·7, 95% CI -2·9 to 1·5; p=0·77), and for performance IQ were 97·5 (12·5) in the iodine group and 99·1 (13·4) in the placebo group (difference -1·6, -4·5 to 1·3; p=0·44). The mean BRIEF-P global executive composite score was 90·6 (26·2) in the iodine group and 91·5 (27·0) in the placebo group (difference -0·9, -6·8 to 5·0; p=0·74). The frequency of adverse events did not differ between groups during gestation or at delivery: 24 women in the iodine group and 28 in the placebo group reported adverse events (iodine group: abortion, n=20; blighted ovum, and n=2; intrauterine death, n=2; placebo group: abortion, n=22; blighted ovum, n=1; intrauterine death, n=2; early neonatal death, n=1; and neonatal death, n=2). INTERPRETATION Daily iodine supplementation in mildly iodine-deficient pregnant women had no effect on child neurodevelopment at age 5-6 years. FUNDING Swiss National Science Foundation, Nestlé Foundation, Wageningen University and Research, and ETH Zurich.
Collapse
Affiliation(s)
- Sueppong Gowachirapant
- Institute of Nutrition, Mahidol University, Nakhon Pathom, Thailand; Division of Human Nutrition, Wageningen University and Research, Wageningen, Netherlands
| | - Nidhi Jaiswal
- Division of Human Nutrition, Wageningen University and Research, Wageningen, Netherlands; St John's Research Institute, Bangalore, India
| | - Alida Melse-Boonstra
- Division of Human Nutrition, Wageningen University and Research, Wageningen, Netherlands
| | - Valeria Galetti
- Department of Health Sciences and Technology, Swiss Federal Institute of Technology (ETH), Zurich, Switzerland
| | - Sara Stinca
- Department of Health Sciences and Technology, Swiss Federal Institute of Technology (ETH), Zurich, Switzerland
| | - Ian Mackenzie
- Hearing Impairment Research Group, Liverpool School of Tropical Medicine, Liverpool, UK
| | | | | | | | | | - Michael B Zimmermann
- Department of Health Sciences and Technology, Swiss Federal Institute of Technology (ETH), Zurich, Switzerland.
| |
Collapse
|
42
|
Brindle E, Lillis L, Barney R, Hess SY, Wessells KR, Ouédraogo CT, Stinca S, Kalnoky M, Peck R, Tyler A, Lyman C, Boyle DS. Simultaneous assessment of iodine, iron, vitamin A, malarial antigenemia, and inflammation status biomarkers via a multiplex immunoassay method on a population of pregnant women from Niger. PLoS One 2017; 12:e0185868. [PMID: 28982133 PMCID: PMC5628875 DOI: 10.1371/journal.pone.0185868] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 09/20/2017] [Indexed: 11/24/2022] Open
Abstract
Deficiencies of vitamin A, iron, and iodine are major public health concerns in many low- and middle-income countries, but information on their status in populations is often lacking due to high costs and logistical challenges associated with assessing micronutrient status. Accurate, user-friendly, and low-cost analytical tools are needed to allow large-scale population surveys on micronutrient status. We present the expansion of a 7-plex protein microarray tool for the simultaneous measurement of up to seven biomarkers with relevance to the assessment of the key micronutrients iron, iodine, and vitamin A, and inflammation and malaria biomarkers: α-1-acid glycoprotein, C-reactive protein, ferritin, retinol binding protein 4, soluble transferrin receptor, thyroglobulin, and histidine-rich protein II. Assay performance was assessed using international reference standards and then verified by comparing the multiplexed and conventional immunoassay results on a training panel of plasma samples collected from US adults. These data were used to assign nominal concentrations to the calibrators of the assay to further improve performance which was then assessed by interrogating plasma samples from a cohort of pregnant women from Niger. The correlation between assays for each biomarker measured from this cohort was typically good, with the exception of thyroglobulin, and the sensitivity ranged from 74% to 93%, and specificity from 81% to 98%. The 7-Plex micronutrient assay has the potential for use as an affordable tool for population surveillance of vitamin A, iron, and iodine deficiencies as well as falciparum malarial parasitemia infectivity and inflammation. The assay is easy-to-use, requires minimal sample volume, and is scalable, rapid, and accurate—needing only a low-cost reader and basic equipment present in most reference laboratory settings and so may be employed by low and middle income countries for micronutrient surveillance to inform on status in key populations. Micronutrient deficiencies including iron, iodine, and vitamin A affect a significant portion of the world’s population. Efforts to assess the prevalence of these deficiencies in vulnerable populations are challenging, partly due to measurement tools that are inadequate for assessing multiple micronutrients in large-scale population surveys. We have developed a 7-plex immunoassay for the simultaneous measurement of seven biomarkers relevant to assessing iodine, iron, and vitamin A status, inflammation and Plasmodium falciparum parasitemia by measuring levels of thyroglobulin, ferritin, soluble transferrin receptor, retinol binding protein 4, α-1-acid glycoprotein, C-reactive protein, and histidine-rich protein II. This 7-plex immunoassay technique has potential as a rapid and effective tool for use in large-scale surveys and assessments of nutrition intervention programs in low- and middle-income countries.
Collapse
Affiliation(s)
- Eleanor Brindle
- Center for Studies in Demography and Ecology, University of Washington, Seattle, WA, United States of America
| | | | | | - Sonja Y. Hess
- Program in International and Community Nutrition, Department of Nutrition, University of California, Davis, CA, United States of America
| | - K. Ryan Wessells
- Program in International and Community Nutrition, Department of Nutrition, University of California, Davis, CA, United States of America
| | - Césaire T. Ouédraogo
- Program in International and Community Nutrition, Department of Nutrition, University of California, Davis, CA, United States of America
- Helen Keller International, Niamey, Niger
| | - Sara Stinca
- Laboratory of Human Nutrition, Swiss Federal Institute of Technology, Zurich, Switzerland
| | | | - Roger Peck
- PATH, Seattle, WA, United States of America
| | - Abby Tyler
- Quansys Biosciences, Logan, Utah, United States of America
| | | | | |
Collapse
|
43
|
Mridha MK, Matias SL, Paul RR, Hussain S, Khan MSA, Siddiqui Z, Ullah B, Sarker M, Hossain M, Young RT, Arnold CD, Dewey KG. Daily Consumption of Lipid-Based Nutrient Supplements Containing 250 μg Iodine Does Not Increase Urinary Iodine Concentrations in Pregnant and Postpartum Women in Bangladesh. J Nutr 2017; 147:1586-1592. [PMID: 28615379 DOI: 10.3945/jn.117.248963] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 03/03/2017] [Accepted: 05/22/2017] [Indexed: 11/14/2022] Open
Abstract
Background: Maternal iodine deficiency during pregnancy and lactation is common in Bangladesh.Objective: We evaluated the effect of lipid-based nutrient supplements for pregnant and lactating women (LNS-PL) on urinary iodine concentration (UIC).Methods: We conducted a cluster-randomized controlled effectiveness trial in which we enrolled 4011 pregnant women at ≤20 gestational weeks. Women in 48 clusters received iron and folic acid (IFA; 60 mg Fe/d + 400 μg folic acid/d) and women in 16 clusters received LNS-PL (20 g/d, 118 kcal) containing 22 vitamins and minerals (including 250 μg I). We randomly selected a subsample of 1159 women for repeated urine sample collection, i.e., at enrollment, at 36 wk of gestation, and at 6 mo postpartum, for UIC analysis, a secondary outcome of the trial.Results: The geometric mean UIC at 36 wk of gestation and at 6 mo postpartum did not differ significantly between the IFA and LNS-PL groups. The median (quartile 1, quartile 3) UIC at 36 wk was 27.4 μg/L (16.9, 52.7 μg/L) in the IFA group and 30.2 μg/L (17.7, 56.6 μg/L) in the LNS-PL group; at 6 mo, these were 23.0 μg/L (10.0, 45.9 μg/L) in the IFA group and 22.2 μg/L (9.1, 50.4 μg/L) in the LNS-PL group.Conclusion: Daily consumption of LNS-PL containing 250 μg I did not increase the UICs of pregnant and lactating women in Bangladesh. Iodine from lipid-based nutrient supplements may have been stored in the thyroid gland or secreted in breast milk instead of being excreted in urine. Additional research that uses other biomarkers of iodine status is needed to determine how to meet the iodine requirements of pregnant and lactating women in Bangladesh and similar settings. This trial was registered at clinicaltrials.gov as NCT01715038.
Collapse
Affiliation(s)
- Malay K Mridha
- Department of Nutrition, University of California, Davis, Davis, CA; and .,Divisions of Nutrition and Clinical Services
| | - Susana L Matias
- Department of Nutrition, University of California, Davis, Davis, CA; and
| | | | | | - Md Showkat Ali Khan
- Health System and Population Studies, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Zakia Siddiqui
- Health System and Population Studies, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Barkat Ullah
- Department of Nutrition, University of California, Davis, Davis, CA; and
| | | | | | - Rebecca T Young
- Department of Nutrition, University of California, Davis, Davis, CA; and
| | - Charles D Arnold
- Department of Nutrition, University of California, Davis, Davis, CA; and
| | - Kathryn G Dewey
- Department of Nutrition, University of California, Davis, Davis, CA; and
| |
Collapse
|
44
|
Katko M, Gazso AA, Hircsu I, Bhattoa HP, Molnar Z, Kovacs B, Andrasi D, Aranyosi J, Makai R, Veress L, Torok O, Bodor M, Samson L, Nagy EV. Thyroglobulin level at week 16 of pregnancy is superior to urinary iodine concentration in revealing preconceptual and first trimester iodine supply. MATERNAL AND CHILD NUTRITION 2017; 14. [PMID: 28593684 PMCID: PMC5763325 DOI: 10.1111/mcn.12470] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 04/26/2017] [Accepted: 05/09/2017] [Indexed: 11/30/2022]
Abstract
Pregnant women are prone to iodine deficiency due to the increased need for iodine during gestation. Progress has recently occurred in establishing serum thyroglobulin (Tg) as an iodine status biomarker, but there is no accepted reference range for iodine sufficiency during pregnancy. An observational study was conducted in 164 pregnant women. At week 16 of gestation urinary iodine concentration (UIC), serum Tg, and thyroid functions were measured, and information on the type of iodine supplementation and smoking were recorded. The parameters of those who started iodine supplementation (≥150 μg/day) at least 4 weeks before pregnancy (n = 27), who started at the detection of pregnancy (n = 51), and who had no iodine supplementation (n = 74) were compared. Sufficient iodine supply was found in the studied population based on median UIC (162 μg/L). Iodine supplementation ≥150 μg/day resulted in higher median UIC regardless of its duration (nonusers: 130 μg/L vs. prepregnancy iodine starters: 240 μg/L, and pregnancy iodine starters: 205 μg/L, p < .001, and p = .023, respectively). Median Tg value of pregnancy starters was identical to that of nonusers (14.5 vs. 14.6 μg/L), whereas prepregnancy starters had lower median Tg (9.1 μg/L, p = .018). Serum Tg concentration at week 16 of pregnancy showed negative relationship (p = .010) with duration of iodine supplementation and positive relationship (p = .008) with smoking, a known interfering factor of iodine metabolism, by multiple regression analysis. Serum Tg at week 16 of pregnancy may be a promising biomarker of preconceptual and first trimester maternal iodine status, the critical early phase of foetal brain development.
Collapse
Affiliation(s)
- Monika Katko
- Division of Endocrinology, Department of Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Andrea Anett Gazso
- Division of Endocrinology, Department of Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Ildiko Hircsu
- Division of Endocrinology, Department of Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Harjit Pal Bhattoa
- Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Zsuzsanna Molnar
- Department of Laboratory Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Bela Kovacs
- Institute of Food Science, University of Debrecen, Debrecen, Hungary
| | - David Andrasi
- Institute of Food Science, University of Debrecen, Debrecen, Hungary
| | | | - Rita Makai
- Kenézy Gyula Hospital, Debrecen, Hungary
| | - Lajos Veress
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Olga Torok
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Miklos Bodor
- Division of Endocrinology, Department of Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Laszlo Samson
- Division of Endocrinology, Department of Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Endre V Nagy
- Division of Endocrinology, Department of Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| |
Collapse
|
45
|
Stinca S, Andersson M, Herter-Aeberli I, Chabaa L, Cherkaoui M, El Ansari N, Aboussad A, Weibel S, Zimmermann MB. Moderate-to-Severe Iodine Deficiency in the "First 1000 Days" Causes More Thyroid Hypofunction in Infants Than in Pregnant or Lactating Women. J Nutr 2017; 147:589-595. [PMID: 28202636 DOI: 10.3945/jn.116.244665] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 12/16/2016] [Accepted: 01/12/2017] [Indexed: 11/14/2022] Open
Abstract
Background: Iodine deficiency early in the life cycle-the "first 1000 days"-can cause hypothyroidism and irreversibly impair neuromotor development. However, the relative vulnerability among women and infants during this critical period is unclear, making it difficult for country-based programs with limited resources to prioritize their iodine interventions.Objective: Our aim was to determine the prevalence of thyroid hypofunction in women and infants living in an area of moderate-to-severe iodine deficiency.Methods: In a cross-sectional survey in Morocco, we measured urinary iodine concentrations (UICs) and concentrations of thyroid-stimulating hormone (TSH) and total or free thyroxine (TT4 or fT4, respectively) in women of reproductive age (n = 156), pregnant women (n = 245), and lactating women (n = 239) and their young infants (n = 239). We calculated daily iodine intakes and measured iodine concentrations in breast milk and household salt. We compared the incidence of hypothyroidism between the 3 groups of women and with the infants.Results: Women of reproductive age, pregnant women, and lactating women had median (IQR) UICs of 41 (29-63), 32 (17-58), and 35 (19-62) μg/L; and estimated iodine intakes were ∼60%, 22%, and 26% of Recommended Nutrient Intakes (RNIs). The infants' median UIC was 73 (28-157) μg/L, which was greater than for all 3 groups of women (P < 0.001), and their dietary intakes were 27% of the RNI. The prevalence of hypothyroidism was not significantly different between the 4 groups, whereas the prevalence of hypothyroxinemia was higher in infants (40%) than in the 3 groups of women (11-14%) (P < 0.001). The median breast-milk iodine concentration was 42 (26-81) μg/L. Only 6% of salt samples were adequately iodized to a concentration of ≥15 ppm; 54% were inadequately iodized and 40% contained no measurable iodine.Conclusions: In an area of moderate-to-severe iodine deficiency, the prevalence of thyroid hypofunction is ∼4-fold higher in young infants compared with the 3 groups of women, suggesting that, in the "first 1000 days," infants are more vulnerable than their mothers and that programs should prioritize iodine prophylaxis for this group.
Collapse
Affiliation(s)
- Sara Stinca
- Laboratory of Human Nutrition, Institute of Food, Nutrition and Health, Swiss Federal Institute of Technology (ETH), Zurich, Switzerland;
| | - Maria Andersson
- Laboratory of Human Nutrition, Institute of Food, Nutrition and Health, Swiss Federal Institute of Technology (ETH), Zurich, Switzerland
| | - Isabelle Herter-Aeberli
- Laboratory of Human Nutrition, Institute of Food, Nutrition and Health, Swiss Federal Institute of Technology (ETH), Zurich, Switzerland
| | - Laila Chabaa
- Mohammed VI University Hospital, Marrakesh, Morocco; and.,Medical and Pharmaceutical Faculty, University Cady Ayyad, Marrakesh, Morocco
| | | | - Nawal El Ansari
- Mohammed VI University Hospital, Marrakesh, Morocco; and.,Medical and Pharmaceutical Faculty, University Cady Ayyad, Marrakesh, Morocco
| | - Abdelmounaim Aboussad
- Mohammed VI University Hospital, Marrakesh, Morocco; and.,Medical and Pharmaceutical Faculty, University Cady Ayyad, Marrakesh, Morocco
| | - Sandra Weibel
- Laboratory of Human Nutrition, Institute of Food, Nutrition and Health, Swiss Federal Institute of Technology (ETH), Zurich, Switzerland
| | - Michael B Zimmermann
- Laboratory of Human Nutrition, Institute of Food, Nutrition and Health, Swiss Federal Institute of Technology (ETH), Zurich, Switzerland;
| |
Collapse
|
46
|
Harding KB, Peña‐Rosas JP, Webster AC, Yap CMY, Payne BA, Ota E, De‐Regil LM. Iodine supplementation for women during the preconception, pregnancy and postpartum period. Cochrane Database Syst Rev 2017; 3:CD011761. [PMID: 28260263 PMCID: PMC6464647 DOI: 10.1002/14651858.cd011761.pub2] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Iodine is an essential nutrient required for the biosynthesis of thyroid hormones, which are responsible for regulating growth, development and metabolism. Iodine requirements increase substantially during pregnancy and breastfeeding. If requirements are not met during these periods, the production of thyroid hormones may decrease and be inadequate for maternal, fetal and infant needs. The provision of iodine supplements may help meet the increased iodine needs during pregnancy and the postpartum period and prevent or correct iodine deficiency and its consequences. OBJECTIVES To assess the benefits and harms of supplementation with iodine, alone or in combination with other vitamins and minerals, for women in the preconceptional, pregnancy or postpartum period on their and their children's outcomes. SEARCH METHODS We searched Cochrane Pregnancy and Childbirth's Trials Register (14 November 2016), and the WHO International Clinical Trials Registry Platform (ICTRP) (17 November 2016), contacted experts in the field and searched the reference lists of retrieved studies and other relevant papers. SELECTION CRITERIA Randomized and quasi-randomized controlled trials with randomisation at either the individual or cluster level comparing injected or oral iodine supplementation (such as tablets, capsules, drops) during preconception, pregnancy or the postpartum period irrespective of iodine compound, dose, frequency or duration. DATA COLLECTION AND ANALYSIS Two review authors independently assessed trial eligibility, risk of bias, extracted data and conducted checks for accuracy. We used the GRADE approach to assess the quality of the evidence for primary outcomes.We anticipated high heterogeneity among trials, and we pooled trial results using random-effects models and were cautious in our interpretation of the pooled results. MAIN RESULTS We included 14 studies and excluded 48 studies. We identified five ongoing or unpublished studies and two studies are awaiting classification. Eleven trials involving over 2700 women contributed data for the comparisons in this review (in three trials, the primary or secondary outcomes were not reported). Maternal primary outcomesIodine supplementation decreased the likelihood of the adverse effect of postpartum hyperthyroidism by 68% (average risk ratio (RR) 0.32; 95% confidence interval (CI) 0.11 to 0.91, three trials in mild to moderate iodine deficiency settings, 543 women, no statistical heterogeneity, low-quality evidence) and increased the likelihood of the adverse effect of digestive intolerance in pregnancy by 15 times (average RR 15.33; 95% CI 2.07 to 113.70, one trial in a mild-deficiency setting, 76 women, very low-quality evidence).There were no clear differences between groups for hypothyroidism in pregnancy or postpartum (pregnancy: average RR 1.90; 95% CI 0.57 to 6.38, one trial, 365 women, low-quality evidence, and postpartum: average RR 0.44; 95% CI 0.06 to 3.42, three trials, 540 women, no statistical heterogeneity, low-quality evidence), preterm birth (average RR 0.71; 95% CI 0.30 to 1.66, two trials, 376 women, statistical heterogeneity, low-quality evidence) or the maternal adverse effects of elevated thyroid peroxidase antibodies (TPO-ab) in pregnancy or postpartum (average RR 0.95; 95% CI 0.44 to 2.07, one trial, 359 women, low-quality evidence, average RR 1.01; 95% CI 0.78 to 1.30, three trials, 397 women, no statistical heterogeneity, low-quality evidence), or hyperthyroidism in pregnancy (average RR 1.90; 95% CI 0.57 to 6.38, one trial, 365 women, low-quality evidence). All of the trials contributing data to these outcomes took place in settings with mild to moderate iodine deficiency. Infant/child primary outcomesCompared with those who did not receive iodine, those who received iodine supplements had a 34% lower likelihood of perinatal mortality, however this difference was not statistically significant (average RR 0.66; 95% CI 0.42 to 1.03, two trials, 457 assessments, low-quality evidence). All of the perinatal deaths occurred in one trial conducted in a severely iodine-deficient setting. There were no clear differences between groups for low birthweight (average RR 0.56; 95% CI 0.26 to 1.23, two trials, 377 infants, no statistical heterogeneity, low-quality evidence), neonatal hypothyroidism/elevated thyroid-stimulating hormone (TSH) (average RR 0.58; 95% CI 0.11 to 3.12, two trials, 260 infants, very low-quality evidence) or the adverse effect of elevated neonatal thyroid peroxidase antibodies (TPO-ab) (average RR 0.61; 95% CI 0.07 to 5.70, one trial, 108 infants, very low-quality evidence). All of the trials contributing data to these outcomes took place in areas with mild to moderate iodine deficiency. No trials reported on hypothyroidism/elevated TSH or any adverse effect beyond the neonatal period. AUTHORS' CONCLUSIONS There were insufficient data to reach any meaningful conclusions on the benefits and harms of routine iodine supplementation in women before, during or after pregnancy. The available evidence suggested that iodine supplementation decreases the likelihood of postpartum hyperthyroidism and increases the likelihood of the adverse effect of digestive intolerance in pregnancy - both considered potential adverse effects. We considered evidence for these outcomes low or very low quality, however, because of study design limitations and wide confidence intervals. In addition, due to the small number of trials and included women in our meta-analyses, these findings must be interpreted with caution. There were no clear effects on other important maternal or child outcomes though these findings must also be interpreted cautiously due to limited data and low-quality trials. Additionally, almost all of the evidence came from settings with mild or moderate iodine deficiency and therefore may not be applicable to settings with severe deficiency.More high-quality randomised controlled trials are needed on iodine supplementation before, during and after pregnancy on maternal and infant/child outcomes. However, it may be unethical to compare iodine to placebo or no treatment in severe deficiency settings. Trials may also be unfeasible in settings where pregnant and lactating women commonly take prenatal supplements with iodine. Information is needed on optimal timing of initiation as well as supplementation regimen and dose. Future trials should consider the outcomes in this review and follow children beyond the neonatal period. Future trials should employ adequate sample sizes, assess potential adverse effects (including the nature and extent of digestive intolerance), and be reported in a way that allows assessment of risk of bias, full data extraction and analysis by the subgroups specified in this review.
Collapse
Affiliation(s)
- Kimberly B Harding
- Micronutrient InitiativeResearch and Evaluation180 Elgin Street, Suite 1000OttawaONCanadaK2P 2K3
| | - Juan Pablo Peña‐Rosas
- World Health OrganizationEvidence and Programme Guidance, Department of Nutrition for Health and Development20 Avenue AppiaGenevaGESwitzerland1211
| | - Angela C Webster
- The University of SydneySydney School of Public HealthEdward Ford Building A27SydneyNSWAustralia2006
| | - Constance MY Yap
- Westmead HospitalDepartment of Diabetes and EndocrinologyCorner Hawkesbury and Darcy RoadsWestmeadNSWAustralia2145
| | - Brian A Payne
- Ministry of Health BarbadosNational Nutrition CenterSt MichaelBarbados
| | - Erika Ota
- St. Luke's International University, Graduate School of Nursing SciencesGlobal Health Nursing10‐1 Akashi‐choChuo‐KuTokyoJapan104‐0044
| | - Luz Maria De‐Regil
- Micronutrient InitiativeResearch and Evaluation180 Elgin Street, Suite 1000OttawaONCanadaK2P 2K3
| | | |
Collapse
|