Incidence and characteristics of vitamin D deficiency rickets in New Zealand children: a New Zealand Paediatric Surveillance Unit study

Adherence to Vitamin D Supplementation Recommendations for Breastfed Infants and Young Children: An Analysis of Canadian Community Health Survey Data Cycles From 2015 to 2018

BACKGROUND

In Canada, nutrition policy, as outlined in the Nutrition for Healthy Term Infants recommendations, includes a daily vitamin D supplement of 10 μg (400 IU) for breastfed infants and young children to support adequate vitamin D status.

OBJECTIVES

This study aimed to report on adherence to vitamin D supplementation recommendations for breastfed infants (≤12 months); and for children breastfed >12 mo.

METHODS

Canadian Community Health Survey (paired-cycles 2015/2016 and 2017/2018) maternal experiences data for infants born 2012-2018 who received any breastmilk formed the sample (n = 7079). Whether the infant was given a vitamin D supplement (yes/no) and the frequency (daily/almost every day, 1-2/wk, or <1/wk) were surveyed. Weighted data (95% CI) were summarized according to breastfeeding history (exclusive to 6 mo and continuing; partial to 6 mo and continuing; and stopped ≤6 mo). Correlates of supplement adherence were explored using logistic regression.

RESULTS

Overall, 87.1% (95% CI: 85.9%, 88.3%) of participants reported giving their infant (≤12 mo) a vitamin D supplement, and of these, 83.3% (95% CI: 81.9%, 84.7%) did so daily/almost every day, 12.4% (95% CI: 11.1%, 13.7%) did so 1-2/wk, and 4.3% (95% CI: 3.6%, 5.0%) did so <1/wk. Lower adjusted odds of adherence were observed among participants reporting: stopped breastfeeding ≤6 mo, lower education or income, recent immigration, and overweight prepregnancy body mass index; higher odds of adherence were observed in the western provinces. Regarding mothers of children >12 mo and breastfed (n = 2312), 58.0% (95% CI: 54.9%, 61.1%) gave a vitamin D supplement daily/almost every day.

CONCLUSIONS

Adherence to providing a vitamin D supplement to breastfed infants is high in Canada. Nonetheless, we estimate that ∼27% of mothers are nonadherent to daily/almost every day administration of a vitamin D supplement and that adherence declines in children breastfed >12 mo. Further promotion to support uptake of the current guidance may be necessary, particularly for parents of recent immigration or lower socioeconomic status.

Serum 25-hydroxyvitamin D threshold and risk of rickets in young children: a systematic review and individual participant data meta-analysis to inform the development of dietary requirements for vitamin D

PURPOSE

The objective of this systematic review was to determine a minimum serum 25-hydroxyvitamin D (25OHD) threshold based on the risk of having rickets in young children. This work was commissioned by the WHO and FAO within the framework of the update of the vitamin D requirements for children 0-3 years old.

METHODS

A systematic search of Embase was conducted to identify studies involving children below  4 years of age with serum 25OHD levels and radiologically confirmed rickets, without any restriction related to the geographical location or language. Study-level and individual participant data (IPD)-level random effects multi-level meta-analyses were conducted. The odds, sensitivity and specificity for rickets at different serum 25OHD thresholds were calculated for all children as well as for children with adequate calcium intakes only.

RESULTS

A total of 120 studies with 5412 participants were included. At the study-level, children with rickets had a mean serum 25OHD of 23 nmol/L (95% CI 19-27). At the IPD level, children with rickets had a median and mean serum 25OHD of 23 and 29 nmol/L, respectively. More than half (55%) of the children with rickets had serum 25OHD below 25 nmol/L, 62% below 30 nmol/L, and 79% below 40 nmol/L. Analysis of odds, sensitivities and specificities for nutritional rickets at different serum 25OHD thresholds suggested a minimal risk threshold of around 28 nmol/L for children with adequate calcium intakes and 40 nmol/L for children with low calcium intakes.

CONCLUSION

This systematic review and IPD meta-analysis suggests that from a public health perspective and to inform the development of dietary requirements for vitamin D, a minimum serum 25OHD threshold of around 28 nmol/L and above would represent a low risk of nutritional rickets for the majority of children with an adequate calcium intake.

Adherence to vitamin D supplementation guidelines in children under five years of age: a systematic literature review

PURPOSE

Despite the presence of guidelines on vitamin D supplementation in infants and young children, little is known about parental adherence to their recommendations. This review aims to summarise the evidence from observational studies investigating adherence to vitamin D supplementation guidelines in children under five years of age.

METHODS

Databases of PubMed, Scopus, Web of Science, and CINAHL were searched from January 2000 until July 2022. Qualitative data synthesis was used to summarise evidence on supplementation adherence. The adherence rate was categorised as low, moderate, and high if it was ≤ 50%, between 50 and 70%, and ≥ 70%, respectively.

RESULTS

Eleven studies investigating adherence to eight different vitamin D supplementation guidelines from European countries, USA and Canada were included. The majority of studies were cross-sectional and conducted among infants. Overall, the adherence rate ranged between 14.29% and 95.6%. Low, moderate, and high adherence to supplementation guidelines were reported in six, three, and two studies, respectively.

CONCLUSION

There is generally poor adherence to vitamin D supplementation guidelines in children under five years of age. Nevertheless, the evidence comes from a limited number of studies, mainly conducted in infants, with high methodological heterogeneity in terms of the vitamin D supplementation guideline assessed and the definition of supplementation adherence in the study population. Further research is warranted to identify effective health promotion interventions to increase supplementation adherence and reduce the risk of vitamin D deficiency at this critical life stage.

Rickets Types and Treatment with Vitamin D and Analogues

The definition of "Vitamin D" encompasses a group of fat-soluble steroid compounds of different origins with similar chemical structures and the same biological effects. Vitamin D deficiency and/or a defect in the process of its synthesis or transport predispose individuals to several types of rickets. In addition to cholecalciferol, ergocalciferol, and vitamins D3 and D2, there are also active metabolites for the treatment of this condition which are commercially available. Calcitriol and aphacalcidiol are active metabolites that do not require the renal activation step, which is required with calcifediol, or hepatic activation. The purpose of this review is to summarize current approaches to the treatment of rickets for generalist physicians, focusing on the best vitamin D form to be used in each type, or, in the case of X-linked hypophosphatemic rickets (XLH), on both conventional and innovative monoclonal antibody treatments.

Hereditary Rickets: A Quick Guide for the Pediatrician

With the increased discovery of genes implicated in vitamin D metabolism and the regulation of calcium and phosphate homeostasis, a growing number of genetic forms of rickets are now recognized. These are categorized into calciopenic and phosphopenic rickets. Calciopenic forms of hereditary rickets are caused by genetic mutations that alter the enzymatic activity in the vitamin D activation pathway or impair the vitamin D receptor action. Hereditary forms of phosphopenic rickets, on the other hand, are caused by genetic mutations that lead to increased expression of FGF23 hormone or that impair the absorptive capacity of phosphate at the proximal renal tubule. Due to the clinical overlap between acquired and genetic forms of rickets, identifying children with hereditary rickets can be challenging. A clear understanding of the molecular basis of hereditary forms of rickets and their associated biochemical patterns allow the health care provider to assign the correct diagnosis, avoid non-effective interventions and shorten the duration of the diagnostic journey in these children. In this mini-review, known forms of hereditary rickets listed on the Online Mendelian Inheritance in Man database are discussed. Further, a clinical approach to identify and diagnose children with hereditary forms of rickets is suggested.

A nutritional supplement during preconception and pregnancy increases human milk vitamin D but not B-vitamin concentrations

BACKGROUND & AIMS

Optimal maternal vitamin status during pregnancy and lactation is essential to support maternal and infant health. For instance, vitamin D3 is involved in infant bone development, and B-vitamins are involved in various metabolic processes, including energy production. Through a double-blind randomised controlled trial, we investigated the effects of maternal supplementation from preconception throughout pregnancy until birth on human milk (HM) concentrations of vitamin D3 and B-vitamins. In addition, we aimed to characterise longitudinal changes in milk concentrations of these vitamins.

METHODS

Both control and intervention supplements contained calcium, iodine, iron, β-carotene, and folic acid, while the intervention also contained zinc, vitamins B2, B6, B12, and D3, probiotics, and myo-inositol. HM samples were collected across 4 time points from 1 week to 3 months post-delivery from 158 mothers in Singapore, and 7 time points from 1 week to 12 months from 180 mothers in New Zealand. HM vitamin D was quantified using supercritical fluid chromatography and B-vitamins with mass spectrometry. Potential intervention effects on HM vitamins D3, B2, B6, and B9, as well as other B-vitamin (B1 and B3) concentrations were assessed using linear mixed models with a repeated measures design.

RESULTS

Over the first 3 months of lactation, HM 25-hydroxyvitamin D3 concentrations were 20% (95% CI 8%, 33%, P = 0.001) higher in the intervention group, with more marked effects in New Zealand. There were no observed intervention effects on HM concentrations of vitamins B1, B2, B3, B6, and B9. In New Zealand mothers, longitudinally, vitamin D3 concentrations gradually increased from early lactation up to 12 months, while vitamins B1 and B2 peaked at 6 weeks, B3 at 3 weeks, and B6 and B9 at 3 months.

CONCLUSIONS

Maternal supplementation during preconception and pregnancy increased HM vitamin D, but not B-vitamin concentrations in lactation. Further studies are required to examine the discrete benefits of vitamin D supplementation starting preconception vs during pregnancy, and to further characterise the effects of supplementation on later offspring health outcomes.

CLINICAL TRIAL REGISTRATION

Registered at ClinicalTrials.gov on the 16 July 2015 (identifier NCT02509988); Universal Trial Number U1111-1171-8056. This study was academic-led by the EpiGen Global Research Consortium.

Nutritional rickets masquerading as spinal muscular atrophy type III

Muscle atrophy, weakness, and loss of ambulation in the pediatric population are signs of progressive neuromuscular diseases. Rapid identification of such diseases is important to prevent further progression. In pediatric neurology, it is well understood to include neuromuscular disorders in the differential for such presentations. We report a case of severe nutritional rickets that mimicked the presentation of spinal muscular atrophy type III and discuss the importance of including rickets in the differential for muscle atrophy and loss of ambulation. A 33-month-old African American boy with several months of gait abnormality was referred to outpatient neurology. The initial diagnostic evaluation focused primarily on neuromuscular disorders, specifically SMA type III, given the absence of reflexes on examination and the history of prior ambulation. After an unfruitful genetic workup, it was elucidated that the child had very poor dietary intake and minimal sun exposure causing nutritional rickets that improved with intervention.

The role of dietary calcium in the etiology of childhood rickets in the past and the present

For more than two centuries, lack of sunlight has been understood to cause vitamin D deficiency and documented as a primary cause of rickets. As such, evidence of rickets in the archeological record has been used as a proxy for vitamin D status in past individuals and populations. In the last decade, a clinical global consensus has emerged wherein it is recognized that dietary calcium deficiency also plays a role in the manifestation of rickets and classic skeletal deformities may not form if dietary calcium is normal even if vitamin D is deficient. This disease is now clinically called "nutritional rickets" to reflect the fact that rickets can take calcium deficiency-predominant or vitamin D deficiency-predominant forms. However, there are currently no paleopathological studies wherein dietary calcium deficiency is critically considered a primary etiology of the disease. We review here the interplay of calcium, vitamin D, and phosphorous in bone homeostasis, examine the role of dietary calcium in human health, and critically explore the clinical literature on calcium deficiency-predominant rickets. Finally, we report a case of rickets from the late Formative Period (~2500-1500 years ago) of the Atacama Desert and argue the disease in this infant is likely an example of calcium deficiency-predominant rickets. We conclude that most archeological cases of rickets are the result of multiple micronutrient deficiencies that compound to manifest in macroscopic skeletal lesions. For clinicians, these factors are important for implementing best treatment practice, and for paleopathologists they are necessary for appropriate interpretation of health in past communities.

Vitamin D Intake and Meeting Recommendations Among Infants Participating in WIC Nationally

OBJECTIVE

To report and examine associations with infant vitamin D intake and meeting recommendations among a national sample participating in Special Supplemental Nutrition Program for Women, Infants, and Children (WIC).

DESIGN

Secondary analysis from the 2013-2015 WIC Infant Toddler Feeding Practices Study-2.

PARTICIPANTS

US Infants.

VARIABLES MEASURED

Total reported vitamin D intake from diet and supplementation at the time of data collection.

ANALYSIS

Descriptive statistics and generalized estimating equations.

RESULTS

The median total vitamin D intake ranged from 5.43 (95% confidence interval, 5.40-5.46) mcg/d at month 1 to 8.18 (95% confidence interval, 8.11-8.20) mcg/d at month 13, with 16% to 36% of infants meeting the infant vitamin D recommendation over that time. Overall, 6% to 12% of all participants reported supplementation across all time points. Although most (between 78% to 98%) of supplemented breastfed infants met the recommendation, very few were supplemented as a group. Hence, breastfed infants were less likely to meet the recommendation than those who were formula fed across at time points except month 1 (P < 0.001 for all). Whereas infant age, feeding type, and/or their interaction were significant predictors of both receiving supplementation and meeting the recommendation, mother/caregiver nativity (P = 0.006) and parity (P = 0.01 and P < 0.001) predicted receiving supplementation, and child sex (P < 0.001) and mother/caregiver race/ethnicity (P < 0.001) predicted meeting the recommendation.

CONCLUSIONS AND IMPLICATIONS

Among a national sample of infants participating in WIC between 2013-2015, a high proportion were not meeting the current vitamin D recommendation. The WIC program is 1 resource for promoting strategies for increasing the number of American infants meeting D recommendations, but a coordinated approach involving other health care providers is likely needed. Future research exploring the reason for lack of supplementation, from both the perspective of parents and providers and the clinical impact of low vitamin D intake, is warranted.

Effect of maternal prenatal and postpartum vitamin D supplementation on offspring bone mass and muscle strength in early childhood: follow-up of a randomized controlled trial

BACKGROUND

Maternal vitamin D status during pregnancy and lactation is a modifiable factor that may influence offspring musculoskeletal outcomes. However, few randomized trials have tested the effects of prenatal or postpartum vitamin D supplementation on offspring bone and muscle development.

OBJECTIVES

The aim was to examine hypothesized effects of improvements in early-life vitamin D status on childhood musculoskeletal health in Dhaka, Bangladesh.

METHODS

In a previously completed, double-blind, dose-ranging trial, healthy pregnant women (n = 1300) were recruited at 17-24 weeks' gestation and randomly assigned to a prenatal/postpartum regimen of 0/0, 4200/0, 16,800/0, 28,000/0, or 28,000/28,000 IU cholecalciferol (vitamin D3)/wk until 26 wk postpartum. In this new report, we describe additional follow-up at 4 y of age (n = 642) for longer-term outcomes. Bone mineral content (BMC) and areal bone mineral density (aBMD) were measured by DXA. Grip strength was tested using a hand-held dynamometer. The primary comparison was children of women assigned to 28,000 IU/wk prenatally compared with placebo. Differences are expressed as means and 95% CIs.

RESULTS

Total-body-less-head (TBLH) BMC, TBLH aBMD, and grip strength were similar in the combined high-dose prenatal (28,000/0 and 28,000/28,000 IU/wk) compared with placebo groups (mean difference [95% CI] = 0.61 g [-10.90, 12.13], 0.0004 g/cm2 [-0.0089, 0.0097], and 0.02 kg [-0.26, 0.31], respectively). In dose-ranging analyses, TBLH BMC and aBMD, whole-body BMC and aBMD, and grip strength in each of the prenatal vitamin D groups were not significantly different from placebo (P > 0.05 for all comparisons). Only head aBMD was greater in children of women assigned to the 28,000/28,000-IU regimen compared with placebo (mean difference [95% CI] = 0.024 g/cm2 [0.0009, 0.047], P = 0.042); the effect was attenuated upon adjustment for child height, weight, and sex (P = 0.11).

CONCLUSIONS

Maternal prenatal, with or without postpartum, vitamin D supplementation does not improve child BMC, aBMD, or grip strength at 4 y of age. The MDIG trial and present follow-up study were registered prospectively at www.clinicaltrials.gov as NCT01924013 and NCT03537443, respectively.

Nutritional rickets & osteomalacia: A practical approach to management

Defective mineralization of the growth plate and preformed osteoid result in rickets and osteomalacia, respectively. The leading cause of rickets worldwide is solar vitamin D deficiency and/or dietary calcium deficiency collectively termed as nutritional rickets. Vitamin D deficiency predominates in high-latitude countries in at-risk groups (dark skin, reduced sun exposure, infants and pregnant and lactating women) but is emerging in some tropical countries due to sun avoidance behaviour. Calcium deficiency predominates in tropical countries, especially in the malnourished population. Nutritional rickets can have devastating health consequences beyond bony deformities (swollen wrist and ankle joints, rachitic rosary, soft skull, stunting and bowing) and include life-threatening hypocalcaemic complications of seizures and, in infancy, heart failure due to dilated cardiomyopathy. In children, diagnosis of rickets (always associated with osteomalacia) is confirmed on radiographs (cupping and flaring of metaphyses) and should be suspected in high risk individuals with the above clinical manifestations in the presence of abnormal blood biochemistry (high alkaline phosphatase and parathyroid hormone, low 25-hydroxyvitamin D and calcium and/or low phosphate). In adults or adolescents with closed growth plates, osteomalacia presents with non-specific symptoms (fatigue, malaise and muscle weakness) and abnormal blood biochemistry, but only in extreme cases, it is associated with radiographic findings of Looser's zone fractures. Bone biopsies could confirm osteomalacia at earlier disease stages, for definitive diagnosis. Treatment includes high-dose cholecalciferol or ergocalciferol daily for a minimum of 12 wk or stoss therapy in exceptional circumstances, each followed by lifelong maintenance supplementation. In addition, adequate calcium intake through diet or supplementation should be ensured. Preventative approaches should be tailored to the population needs and incorporate multiple strategies including targeted vitamin D supplementation of at-risk groups and food fortification with vitamin D and/or calcium. Economically, food fortification is certainly the most cost-effective way forward.

Alfacalcidol improves the growth velocity in children with vitamin D deficiency/insufficiency: A single center retrospective cohort study

OBJECTIVES

To investigate the growth velocity-improving effects of vitamin D replacement therapy in pediatric patients diagnosed with vitamin D deficiency and insufficiency.

STUDY DESIGN

A retrospective cohort study was conducted in 34 pediatric patients diagnosed with vitamin D deficiency/insufficiency. Based on the clinical findings, the subjects were divided into two groups: a bowed leg (BL) group and a non-bowed leg (non-BL) group. After the initiation of alfacalcidol, the standard deviation score (SDS) of their heights, weights and growth velocities in each group were monitored.

RESULTS

The median age at the first visit was significantly lesser in the BL group (1.58 years old [interquartile range (IQR): 1.33, 2.17]) than that in the non-BL group (3.00 years old [IQR: 2.33, 3.67]). On the contrary, the SDS for height was significantly lower in the non-BL group (-2.27 [IQR: -2.63, -1.94]) than that in the BL group (-1.37 [IQR: -1.91, -1.07]). One-year treatment with alfacalcidol showed significant improvements in both height SDSs and growth velocity SDSs not only in the BL group but also in the non-BL group.

CONCLUSIONS

The current study revealed that vitamin D replacement therapy improved the growth rate in children with vitamin D deficiency/insufficiency, regardless of the presence of BL. This study emphasizes the importance of assessing the vitamin D status in children with poor growth rates and suggests that alfacalcidol could be a valid option for the treatment of short stature.

Comparison of Vitamin D and 25-Hydroxyvitamin D Concentrations in Human Breast Milk between 1989 and 2016-2017

BACKGROUND

Breast milk is considered the optimal source of nutrition during infancy. Although the vitamin D concentration in human breast milk is generally considered poor for infants, vitamin D in breast milk is an important source for exclusively breastfed infants. Increases in vitamin D insufficiency and deficiency in lactating mothers may reduce vitamin D concentrations in breast milk. This study aimed to compare vitamin D and 25-hydroxyvitamin D (25OHD) concentrations in breast milk collected in 1989 and 2016-2017 and simultaneously analyze them with liquid chromatography-tandem mass spectrometry (LC-MS/MS); the association between the lifestyle of recent lactating mothers (2016-2017) and vitamin D status in human breast milk was also evaluated.

METHOD

Lactating mothers were recruited from three regions of Japan in 1989 (n = 72) and 2016-2017 (n = 90), and milk from 3-4 months was collected in summer and winter. The samples were strictly sealed and stored at -80℃ until measurement. Breast milk vitamin D and 25OHD concentrations were analyzed by LC-MS/MS. Vitamin D intake, sun exposure, and sunscreen use of the lactating mothers in 2016-2017 were assessed.

RESULTS

Both vitamin D and 25OHD concentrations in breast milk were higher in the summer regardless of the survey year. Significantly lower vitamin D and 25OHD concentrations were observed in 2016-2017 compared with 1989 in summer, but no survey year difference was observed in winter. The stepwise multiple regression analyses identified season, daily outdoor activity, and suntan in the last 12 months as independent factors associated with vitamin D₃ concentrations.

CONCLUSION

The results suggest that low vitamin D status in recent lactating mothers may have decreased vitamin D and 25OHD concentrations in breast milk compared with the 1980s. These results are helpful for developing public health strategies to improve vitamin D status in lactating mothers and infants.

Failure of national antenatal vitamin D supplementation programme puts dark skinned infants at highest risk: A newborn bloodspot screening study

OBJECTIVES

To determine the prevalence of vitamin D deficiency on dried blood spots (DBS) obtained at newborn blood spot screening (NBS) and thereby test the efficacy of the UK national antenatal supplementation programme in an increasingly ethnically diverse English population. To evaluate the seasonal and ethnic variation in neonatal plasma 25 hydoxyvitamin D (25OHD) and its determinants.

DESIGN

Three thousand random DBS samples received at a single regional newborn screening laboratory (52° N) over two one-week periods, one in winter (February 2019) and one in summer (August 2019), were collected. Data was collected from NBS cards on birth weight, gestational age, maternal age, ethnicity, and post code which was replaced with index of multiple deprivation (IMD). 25OHD concentrations were measured on 6 mm sub-punch from DBS using quantitative liquid chromatography tandem mass spectrometry adjusted to equivalent plasma values. 25OHD variation with season was assessed using Mann-Whitney U test and ethnic groups compared using Kruskal-Wallis test. Linear regression was used to assess the determinants of 25OHD concentrations.

RESULTS

25OHD measurements were available in 2999 (1580 males) subjects [1499 winter-born and 1500 summer-born]. The majority were white British (59.1%) and born at term (mean ± SD gestational age of 38.8 ± 1.8 weeks) with a mean (±SD) birth weight of 3306 (±565) grams. The overall prevalence of vitamin D deficiency [25OHD<30 nmol/L (12 μg/L)] was 35.7% (n = 1070) and insufficiency [30-50 nmol/L (12-20 μg/L)] 33.7% (n = 1010). The median (IQR) 25OHD concentration was significantly lower in the winter-born compared to summer-born [29.1 (19.8, 40.6) vs 49.2 (34.3, 64.8) nmol/L respectively; p < 0.001]. Across both seasons, when compared to white British babies (41.6 nmol/L), the median 25OHD concentrations were significantly lower in babies of black (30.3 nmol/L; p < 0.001), Asian (31.3 nmol/L; p < 0.001), any other mixed (32.9 nmol/L; p < 0.001), mixed white and black (33.7 nmol/L; p < 0.05) and any other white (37.7 nmol/L; p < 0.05) ethnicity. The proportion of deficiency was also higher in babies of Asian (48%), black (47%) and mixed ethnicity (38-44%) compared to any other white (34%) or white British (30%) ethnicity. Season of birth, ethnicity, gestation and maternal age accounted for almost 24% of the variation in 25OHD concentrations.

CONCLUSION

The current UK antenatal supplementation programme fails to protect newborns from vitamin D deficiency, especially those from minority ethnic groups who are at high risk of vitamin D deficiency. Nearly 70% of all newborns and 85% of winter-borns had 25OHD concentrations below 50 nmol/L (20 μg/L). Almost 50% of babies of Black or Asian origin were deficient at birth, which explains their high risk of hypocalcaemic complications and rickets if left unsupplemented. Our findings call for an immediate review of the delivery of antenatal and infant vitamin D supplementation programmes and implementation of food fortification in the long term.

Global consensus on nutritional rickets: Implications for Australia

In 2016, a global consensus on the prevention, diagnosis and management of nutritional rickets was published. The bone and mineral working group of the Australasian Paediatric Endocrine Group provides a summary and highlights differences to previous Australian and New Zealand (ANZ) guidelines on vitamin D deficiency and their implications for clinicians. Key points are: (i) The International Consensus document is focused on nutritional rickets, whereas the ANZ guidelines were focused on vitamin D deficiency. (ii) Definitions for the interpretation of 25-hydroxy vitamin D (25OHD) levels do not differ between statements. (iii) The global consensus recommends that routine 25OHD screening should not be performed in healthy children and recommendations for vitamin D supplementation are not based solely on 25OHD levels. The Australasian Paediatric Endocrine Group bone and mineral working group supports that screening for vitamin D deficiency should be restricted to populations at risk. (iv) Recommendations from the global consensus for vitamin D dosages for the therapy of nutritional rickets (diagnosed based on history, physical examination, biochemical testing and a confirmation by X-rays) are higher than in ANZ publications. (v) The global consensus recommends the implementation of public health strategies such as universal supplementation with vitamin D from birth to 1 year of age and food fortification. We conclude that updated global recommendations for therapy of nutritional rickets complement previously published position statements for Australia and New Zealand. Screening, management and the implementation of public health strategies need to be further explored for Australia.

Nutritional rickets under 16 years: UK surveillance results

OBJECTIVE

The UK national incidence of nutritional rickets is unknown. We aimed to describe the incidence, presentation and clinical management of children under 16 years with nutritional rickets in the UK presenting to secondary care.

METHODS

Prospective data were collected monthly between March 2015 and March 2017 from 3500 consultant paediatricians using British Paediatric Surveillance Unit methodology. Clinicians completed online clinical questionnaires for cases fitting the surveillance case definition.

RESULTS

125 cases met the case definition, an annual incidence of 0.48 (95% CI 0.37 to 0.62) per 100 000 children under 16 years. 116 children were under 5 years (annual incidence of 1.39 (95% CI 1.05 to 1.81) per 100 000. Boys (70%) were significantly more affected than girls (30%) (OR 2.17, 95% CI 1.25 to 3.78). The majority were of Black (43%) or South Asian (38%) ethnicity. 77.6% of children were not taking vitamin D supplements despite being eligible. Complications included delayed gross motor development (26.4%), fractures (9.6%), hypocalcaemic seizures (8%) and dilated cardiomyopathy (3%). Two children died (1.6%). In eight cases, rickets was confirmed radiologically and biochemically [raised serum alkaline phosphatase (ALP) and parathyroid hormone (PTH) levels ] but were excluded from the incidence analysis for not meeting the case definition of 25-hydroxyvitamin D of <25 nmol/L.

CONCLUSION

The incidence of nutritional rickets in the UK is lower than expected. Serious complications and unexpected deaths, particularly in Black and South Asian children under 5 years, occurred. Both vitamin D deficiency and dietary calcium deficiency are role players in pathogenesis. Uptake of vitamin D supplementation remains low.

Nutritional rickets: Historic overview and plan for worldwide eradication

Rickets was first described in great detail in the mid 17th century and was affecting a great number of children in major European cities. The disease, however, existed already in the Roman times. The etiology of this disease remained enigmatic until the 1920s when two different mechanisms, lack of exposure to sunlight and lack of a dietary factor were finally solved by the discovery of vitamin D and its dual origin. Soon thereafter, the implementation of vitamin D supplementation for all infants and small children largely eliminated nutritional rickets in Europe and North America. It took nearly a century to elucidate the complex chemistry, metabolism, mode and spectrum of activity of the vitamin D endocrine system. Nutritional rickets, whether due to simple vitamin D or calcium deficiency or both, remains widely ravaging many infants and children around the world. Asian countries and the Middle East are mainly confronted with vitamin D deficiency whereas many African and some Asian countries face calcium deficiency rickets. Immigrants and refugees or in general people with a darker skin living in moderate climate zone are also confronted with this disease. There is great consensus how this disease could be prevented or cured. In collaboration with most international professional societies, we prepare a memorandum, in line with the successful battle against iodine deficiency disorders, to convince the World Health Organization and its member states to start an implementation program to eradicate nutritional rickets by 2030.

Vitamin D: Giveth to Those Who Needeth

Severe vitamin D deficiency may cause rickets. While this point is not disputed, the use of vitamin D in the elderly to prevent fractures has been challenged recently by a meta‐analysis of 81 RCTs, suggesting that the effects of vitamin D were trivial. As is true for any review of the literature, the interpretation of a meta‐analysis can be confounded by the choice of publications to include or exclude. Indeed, the authors excluded RCTs with combined vitamin D and calcium supplementation, included futile studies of very short duration, or studies with high bolus doses known to transiently increase fracture risk. The best available data show that calcium and vitamin D supplementation of elderly subjects can decrease the risk of hip and other non‐vertebral fractures, especially in institutionalized subjects or elderly subjects with poor calcium and vitamin D status. Vitamin D deficiency is associated with many chronic diseases. The VIDA and VITAL trials did not show a protective effect on cardiovascular diseases and cancer. The D2d study also did not influence the progress of prediabetes to diabetes. However, the baseline 25OHD concentrations of the majority of the participants of all these trials were essentially normal. Post‐hoc analysis of these studies suggest some possibly beneficial health outcomes in vitamin D deficient subjects. A meta‐analysis suggested that vitamin D could partly prevent upper respiratory infections. Mendelian randomization studies suggest a causal link between lifelong low vitamin D status and multiple sclerosis. A vitamin D supplement in pregnant women may decrease maternal morbidity and improve the health of their offspring. Better‐designed studies are needed to answer all outstanding questions. However, based on all available data, it seems that correction of vitamin D and/or calcium deficiency of infants, pregnant women and elderly subjects can improve their health. © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

The Effect of High-Dose Postpartum Maternal Vitamin D Supplementation Alone Compared with Maternal Plus Infant Vitamin D Supplementation in Breastfeeding Infants in a High-Risk Population. A Randomized Controlled Trial

In view of continuing reports of high prevalence of severe vitamin D deficiency and low rate of infant vitamin D supplementation, an alternative strategy for prevention of vitamin D deficiency in infants warrants further study. The aim of this randomized controlled trial among 95 exclusively breastfeeding mother-infant pairs with high prevalence of vitamin D deficiency was to compare the effect of six-month post-partum vitamin D₃ maternal supplementation of 6000 IU/day alone with maternal supplementation of 600 IU/day plus infant supplementation of 400 IU/day on the vitamin D status of breastfeeding infants in Doha, Qatar. Serum calcium, parathyroid hormone, maternal urine calcium/creatinine ratio and breast milk vitamin D content were measured. At baseline, the mean serum 25-hydroxyvitamin D (25(OH)D) of mothers on 6000 IU and 600 IU (35.1 vs. 35.7 nmol/L) and in their infants (31.9 vs. 29.6) respectively were low but similar. At the end of the six month supplementation, mothers on 6000 IU achieved higher serum 25(OH)D mean ± SD of 98 ± 35 nmol/L than 52 ± 20 nmol/L in mothers on 600 IU (p < 0.0001). Of mothers on 6000 IU, 96% achieved adequate serum 25(OH)D (≥50 nmol/L) compared with 52%in mothers on 600 IU (p < 0.0001). Infants of mothers on 600 IU and also supplemented with 400 IU vitamin D₃ had slightly higher serum 25(OH)D than infants of mothers on 6000 IU alone (109 vs. 92 nmol/L, p = 0.03); however, similar percentage of infants in both groups achieved adequate serum 25(OH)D ≥50 nmol/L (91% vs. 89%, p = 0.75). Mothers on 6000 IU vitamin D₃/day also had higher human milk vitamin D content. Safety measurements, including serum calcium and urine calcium/creatinine ratios in the mother and serum calcium levels in the infants were similar in both groups. Maternal 6000 IU/day vitamin D₃ supplementation alone safely optimizes maternal vitamin D status, improves milk vitamin D to maintain adequate infant serum 25(OH)D. It thus provides an alternative option to prevent the burden of vitamin D deficiency in exclusively breastfeeding infants in high-risk populations and warrants further study of the effective dose.

Current vitamin D status in European and Middle East countries and strategies to prevent vitamin D deficiency: a position statement of the European Calcified Tissue Society

Vitamin D deficiency (serum 25-hydroxyvitamin D (25(OH)D) <50 nmol/L or 20 ng/mL) is common in Europe and the Middle East. It occurs in <20% of the population in Northern Europe, in 30-60% in Western, Southern and Eastern Europe and up to 80% in Middle East countries. Severe deficiency (serum 25(OH)D <30 nmol/L or 12 ng/mL) is found in >10% of Europeans. The European Calcified Tissue Society (ECTS) advises that the measurement of serum 25(OH)D be standardized, for example, by the Vitamin D Standardization Program. Risk groups include young children, adolescents, pregnant women, older people (especially the institutionalized) and non-Western immigrants. Consequences of vitamin D deficiency include mineralization defects and lower bone mineral density causing fractures. Extra-skeletal consequences may be muscle weakness, falls and acute respiratory infection, and are the subject of large ongoing clinical trials. The ECTS advises to improve vitamin D status by food fortification and the use of vitamin D supplements in risk groups. Fortification of foods by adding vitamin D to dairy products, bread and cereals can improve the vitamin D status of the whole population, but quality assurance monitoring is needed to prevent intoxication. Specific risk groups such as infants and children up to 3 years, pregnant women, older persons and non-Western immigrants should routinely receive vitamin D supplements. Future research should include genetic studies to better define individual vulnerability for vitamin D deficiency, and Mendelian randomization studies to address the effect of vitamin D deficiency on long-term non-skeletal outcomes such as cancer.

Spot the silent sufferers: A call for clinical diagnostic criteria for solar and nutritional osteomalacia

Osteomalacia and rickets result from defective mineralization when the body is deprived of calcium. Globally, the main cause of osteomalacia is a lack of mineral supply for bone modeling and remodeling due to solar vitamin D and/or dietary calcium deficiency. Osteomalacia occurs when existing bone is replaced by unmineralized bone matrix (osteoid) during remodeling in children and adults, or when newly formed bone is not mineralized in time during modeling in children. Rickets occurs when hypomineralization affects the epiphyseal growth plate chondrocytes and adjacent bone metaphysis in growing children. Hence, osteomalacia co-exists with rickets in growing children. Several reports in the last decade highlight the resurgence of so-called "nutritional" rickets in the dark-skinned population living in high-income countries. However, very few studies have ever explored the hidden iceberg of nutritional osteomalacia in the population. Rickets presents with hypocalcaemic (seizures, tetany, cardiomyopathy), or hypophosphataemic complications (leg bowing, knock knees, rachitic rosary, muscle weakness) and is diagnosed on radiographs (cupping and fraying of metaphyses). In contrast, osteomalacia lacks distinctive, non-invasive diagnostic laboratory or imaging criteria and the clinical presentation is non-specific (general fatigue, malaise, muscle weakness and pain). Hence, osteomalacia remains largely undiagnosed, as a hidden disease in millions of dark-skinned people who are at greatest risk. Radiographs may demonstrate Looser's zone fractures in those most severely affected, however to date, osteomalacia remains a histological diagnosis requiring a bone biopsy. Biochemical features of high serum alkaline phosphatase (ALP), high parathyroid hormone (PTH) with or without low 25 hydroxyvitamin D (25OHD) concentrations are common to both rickets and osteomalacia. Here, we propose non-invasive diagnostic criteria for osteomalacia. We recommend a diagnosis of osteomalacia in the presence of high ALP, high PTH, low dietary calcium intake (<300 mg/day) and/or low serum 25OHD (<30 nmol/L). Presence of clinical symptoms (as above) or Looser's zone fractures should be used to reaffirm the diagnosis. We call for further studies to explore the true prevalence of nutritional osteomalacia in various populations, specifically the Black and Asian ethnic groups, in order to identify the hidden disease burden and inform public health policies for vitamin D/calcium supplementation and food fortification.

A Brief History of Nutritional Rickets

Since first described almost a century ago, vitamin D preparations have been successfully used as a public health intervention to prevent nutritional rickets. In this manuscript, we document the periods in history when nutritional rickets was described, examine early efforts to understand its etiology and the steps taken to treat and prevent it. We will also highlight that despite the wealth of historical data and multiple preventative strategies, nutritional rickets remains a significant public health disorder. Nutritional rickets has both skeletal and extraskeletal manifestations. While the skeletal manifestations are the most recognized features, it is the extraskeletal complications, hypocalcaemic seizure and cardiomyopathy that are the most devastating features and result in reported fatalities. Reviewing this history provides an opportunity to further promote recent global consensus recommendations for the prevention and management of nutritional rickets, as well as gain a greater understanding of the well-known public health measures that can be used to manage this entirely preventable disease.

Global prevalence and disease burden of vitamin D deficiency: a roadmap for action in low- and middle-income countries

Vitamin D is an essential nutrient for bone health and may influence the risks of respiratory illness, adverse pregnancy outcomes, and chronic diseases of adulthood. Because many countries have a relatively low supply of foods rich in vitamin D and inadequate exposure to natural ultraviolet B (UVB) radiation from sunlight, an important proportion of the global population is at risk of vitamin D deficiency. There is general agreement that the minimum serum/plasma 25-hydroxyvitamin D concentration (25(OH)D) that protects against vitamin D deficiency-related bone disease is approximately 30 nmol/L; therefore, this threshold is suitable to define vitamin D deficiency in population surveys. However, efforts to assess the vitamin D status of populations in low- and middle-income countries have been hampered by limited availability of population-representative 25(OH)D data, particularly among population subgroups most vulnerable to the skeletal and potential extraskeletal consequences of low vitamin D status, namely exclusively breastfed infants, children, adolescents, pregnant and lactating women, and the elderly. In the absence of 25(OH)D data, identification of communities that would benefit from public health interventions to improve vitamin D status may require proxy indicators of the population risk of vitamin D deficiency, such as the prevalence of rickets or metrics of usual UVB exposure. If a high prevalence of vitamin D deficiency is identified (>20% prevalence of 25(OH)D < 30 nmol/L) or the risk for vitamin D deficiency is determined to be high based on proxy indicators (e.g., prevalence of rickets >1%), food fortification and/or targeted vitamin D supplementation policies can be implemented to reduce the burden of vitamin D deficiency-related conditions in vulnerable populations.

Vitamin D insufficiency: Definition, diagnosis and management

Severe vitamin D deficiency can be defined as the dose of vitamin D or serum 25OHD concentrations needed to prevent nutritional rickets or osteomalacia. There is large international consensus that these diseases can be prevented by 400 IU of vitamin D/d and 25OHD above 30 nmol/l (12 ng/ml). Vitamin D deficiency can also accelerate the risk of fractures and probably also of falls in elderly subjects but there is no consensus on the required daily doses or minimal 25OHD threshold for these endpoints. The majority of experts consider 800 IU/d and serum 25OHD above 50 nmol/l (20 ng/ml) as sufficient, with a minority opinion aiming for 75 nmol/l or even higher. For other extra-skeletal endpoints, no hard evidence is available to define whether or not this is causally related to vitamin D status. Therefore, for these endpoints no minimal dosage or 25OHD threshold can be defined.

Incidence rate and characteristics of symptomatic vitamin D deficiency in children: a nationwide survey in Japan

There is concern that vitamin D deficiency is prevalent among children in Japan as well as worldwide. We conducted a nationwide epidemiologic survey of symptomatic vitamin D deficiency to observe its incidence rate among Japanese children. A questionnaire inquiring the number of new patients with vitamin D deficiency rickets and/or hypocalcemia for 3 years was sent to 855 randomly selected hospitals with a pediatrics department in Japan. In this survey, we found that 250 children were diagnosed with symptomatic vitamin D deficiency. The estimated number of patients with symptomatic vitamin D deficiency per year was 183 (95% confidence interval (CI): 145-222). The overall annual incidence rate among children under 15 years of age was 1.1 per 100,000 population (95% CI: 0.9-1.4). The second survey has provided detailed information on 89 patients with symptomatic vitamin D deficiency under 5 years of age in hospitals in the current research group. The nationwide and second surveys estimated the overall annual incidence rate of symptomatic vitamin D deficiency in children under 5 years of age to be 3.5 (2.7-4.2) per 100,000 population. The second survey revealed 83% had bowed legs, 88% had exclusive breastfeeding, 49% had a restricted and/or unbalanced diet and 31% had insufficient sun exposure among the 89 patients. This is the first nationwide survey on definitive clinical vitamin D deficiency in children in Japan. Elucidating the frequency and characteristics of symptomatic vitamin D deficiency among children is useful to develop preventative public health strategies.

Cardiac, bone and growth plate manifestations in hypocalcemic infants: revealing the hidden body of the vitamin D deficiency iceberg

BACKGROUND

Whilst hypocalcemic complications from vitamin D deficiency are considered rare in high-income countries, they are highly prevalent among Black, Asian and Minority Ethnic (BAME) group with darker skin. To date, the extent of osteomalacia in such infants and their family members is unknown. Our aim was to investigate clinical, cardiac and bone histomorphometric characteristics, bone matrix mineralization in affected infants and to test family members for biochemical evidence of osteomalacia.

CASE PRESENTATION

Three infants of BAME origin (aged 5-6 months) presented acutely in early-spring with cardiac arrest, respiratory arrest following seizure or severe respiratory distress, with profound hypocalcemia (serum calcium 1.22-1.96 mmol/L). All infants had dark skin and vitamin D supplementation had not been addressed during child surveillance visits. All three had severely dilated left ventricles (z-scores + 4.6 to + 6.5) with reduced ejection fraction (25-30%; normal 55-70), fractional shortening (7 to 15%; normal 29-40) and global hypokinesia, confirming hypocalcemic dilated cardiomyopathy. They all had low serum levels of 25 hydroxyvitamin D (25OHD < 15 nmol/L), and elevated parathyroid hormone (PTH; 219-482 ng/L) and alkaline phosphatase (ALP; 802-1123 IU/L), with undiagnosed rickets on radiographs. One infant died from cardiac arrest. At post-mortem examination, his growth plate showed a widened, irregular zone of hypertrophic chondrocytes. Histomorphometry and backscattered electron microscopy of a trans-iliac bone biopsy sample revealed increased osteoid thickness (+ 262% of normal) and osteoid volume/bone volume (+ 1573%), and extremely low bone mineralization density. Five of the nine tested family members had vitamin D deficiency (25OHD < 30 nmol/L), three had insufficiency (< 50 nmol/L) and 6/9 members had elevated PTH and ALP levels.

CONCLUSIONS

The severe, hidden, cardiac and bone pathology described here exposes a failure of public health prevention programs, as complications from vitamin D deficiency are entirely preventable by routine supplementation. The family investigations demonstrate widespread deficiency and undiagnosed osteomalacia in ethnic risk groups and call for protective legislation.

Rickets

Rickets is a bone disease associated with abnormal serum calcium and phosphate levels. The clinical presentation is heterogeneous and depends on the age of onset and pathogenesis but includes bowing deformities of the legs, short stature and widening of joints. The disorder can be caused by nutritional deficiencies or genetic defects. Mutations in genes encoding proteins involved in vitamin D metabolism or action, fibroblast growth factor 23 (FGF23) production or degradation, renal phosphate handling or bone mineralization have been identified. The prevalence of nutritional rickets has substantially declined compared with the prevalence 200 years ago, but the condition has been re-emerging even in some well-resourced countries; prematurely born infants or breastfed infants who have dark skin types are particularly at risk. Diagnosis is usually established by medical history, physical examination, biochemical tests and radiography. Prevention is possible only for nutritional rickets and includes supplementation or food fortification with calcium and vitamin D either alone or in combination with sunlight exposure. Treatment of typical nutritional rickets includes calcium and/or vitamin D supplementation, although instances infrequently occur in which phosphate repletion may be necessary. Management of heritable types of rickets associated with defects in vitamin D metabolism or activation involves the administration of vitamin D metabolites. Oral phosphate supplementation is usually indicated for FGF23-independent phosphopenic rickets, whereas the conventional treatment of FGF23-dependent types of rickets includes a combination of phosphate and activated vitamin D; an anti-FGF23 antibody has shown promising results and is under further study.

Ethnic disparities in the dietary requirement for vitamin D during pregnancy: considerations for nutrition policy and research

Despite the inverse association between skin colour and efficiency of cutaneous vitamin D synthesis, in addition to the widely accepted racial disparity in vitamin D status, populations of ethnic minority are understudied in terms of setting target serum 25-hydroxyvitamin D concentrations and corresponding dietary requirements for vitamin D. In minority groups, prevention of vitamin D deficiency on a population basis is challenging due to the lack of clarity surrounding the metabolism and transport of vitamin D. Authoritative agencies have been unable to define pregnancy-specific dietary recommendations for vitamin D, owing to an absence of sufficient evidence to confirm whether nutritional requirements for vitamin D are altered during pregnancy. While the question of setting race- and pregnancy-specific dietary reference values for vitamin D has not been addressed to date, endemic vitamin D deficiency has been reported among gravidae worldwide, specifically among ethnic minorities and white women resident at high latitude. In light of the increased risk of nutritional rickets among infants of ethnic minority, coupled with growing evidence for potential non-skeletal roles of vitamin D in perinatal health, determination of the dietary vitamin D requirement that will prevent deficiency during pregnancy is a research priority. However, systematic approaches to establishing dietary requirements are limited by the quality of the available evidence and the under-representation of minority groups in clinical research. This review considers the evidence for racial differences in vitamin D status and response to vitamin D supplementation, with particular application to pregnancy-specific requirements among ethnic minorities resident at high latitudes.

Nutritional Rickets and Osteomalacia in the Twenty-first Century: Revised Concepts, Public Health, and Prevention Strategies

PURPOSE OF REVIEW

Nutritional rickets and osteomalacia are common in dark-skinned and migrant populations. Their global incidence is rising due to changing population demographics, failing prevention policies and missing implementation strategies. The calcium deprivation spectrum has hypocalcaemic (seizures, tetany and dilated cardiomyopathy) and late hypophosphataemic (rickets, osteomalacia and muscle weakness) complications. This article reviews sustainable prevention strategies and identifies areas for future research.

RECENT FINDINGS

The global rickets consensus recognises the equal contribution of vitamin D and dietary calcium in the causation of calcium deprivation and provides a three stage categorisation for sufficiency, insufficiency and deficiency. For rickets prevention, 400 IU daily is recommended for all infants from birth and 600 IU in pregnancy, alongside monitoring in antenatal and child health surveillance programmes. High-risk populations require lifelong supplementation and food fortification with vitamin D or calcium. Future research should identify the true prevalence of rickets and osteomalacia, their role in bone fragility and infant mortality, and best screening and public health prevention tools.

Comparative analysis of nutritional guidelines for vitamin D

Vitamin D is essential for calcium and bone homeostasis. Humans are largely dependent on UVB-radiation-induced photosynthesis of vitamin D, as few foods contain vitamin D. However, the same radiation that produces vitamin D is also carcinogenic, albeit with a long lag time, and causes DNA damage. In view of the increasing life expectancy, avoiding excessive sun exposure is prudent. Several groups of people have a shortfall between their requirements for vitamin D and their combined endogenous synthesis and intake from natural foods, and therefore need vitamin D supplementation. Governments and scientific societies are regularly updating their recommendations for intake of vitamin D, especially for groups that should (infants) or prefer to (especially elderly individuals) avoid direct sunlight. An overview of such guidelines is presented in this Review. A fairly large consensus exists that all infants should receive 400 international units (IU) (10 μg) daily during their first year of life and that elderly individuals should have access to vitamin D supplementation (at recommended dosages varying from 400 IU to 800 IU daily in most governmental guidelines but at higher dosages in other guidelines). All guidelines unanimously agree that serum levels of 25-hydroxyvitamin D (25OHD) <25 nmol/l (10 ng/ml) should be avoided at all ages. Children and adults who have limited sun exposure should receive vitamin D supplementation, but the recommended doses vary widely (from 200 IU to 2,000 IU daily), in line with disagreement regarding the minimal desirable serum concentration of 25OHD (which varies from 25 nmol/l to >100 nmol/l).

Vitamin D-Deficient Rickets in Japan

Objectives: Our study aimed to clarify the trend of vitamin D deficiency and rickets diagnosed in the past 10 years. Methods: This observational study used health insurance claims data from 2005 to 2014. The number of beneficiaries for 2005 and 2014 were 91 617 and 365 800, respectively. We included children aged 0 to 15 years diagnosed with vitamin D deficiency or vitamin D-deficient rickets; those with congenital/secondary rickets and low-birth-weight infants were excluded. We analyzed the number of patients and the temporal trend of these diseases in Japan. Results: The annual number of patients from 2005 to 2008 was <5. The number of patients in 2009 and 2014 were 3.88 (95% confidence interval = 1.77-7.37) and 12.30/100 000 (95% confidence interval = 8.97-16.46), respectively. Conclusions: Diagnosed cases of vitamin D deficiency and vitamin D-deficient rickets have apparently increased in Japan. Further studies to identify the trend, cause, and prevention of vitamin D-deficient rickets are necessary.

Trends in the Diagnosis of Vitamin D Deficiency

BACKGROUND

Vitamin D has attracted considerable interest in recent years, and health care providers have reported large increases in vitamin D test requests. However, rates of diagnosis of vitamin D deficiency in clinical practice have not been investigated. We examined trends in diagnosis of vitamin D deficiency in children in England over time, and by sociodemographic characteristics.

METHODS

Cohort study using primary care records of 711 788 children aged 0 to 17 years, from the Health Improvement Network database. Incidence rates for diagnosis of vitamin D deficiency were calculated per year between 2000 and 2014. Rate ratios exploring differences by age, sex, ethnicity, and social deprivation were estimated using multivariable Poisson regression.

RESULTS

The crude rate of vitamin D deficiency diagnosis increased from 3.14 per 100 000 person-years in 2000 (95% confidence interval [CI], 1.31-7.54) to 261 per 100 000 person-years in 2014 (95% CI, 241-281). After accounting for changes in demographic characteristics, a 15-fold (95% CI, 10-21) increase in diagnosis was seen between 2008 and 2014. Older age (≥10 years), nonwhite ethnicity, and social deprivation were independently associated with higher rates of diagnosis. In children aged <5 years, diagnosis rates were higher in boys than girls, whereas in children aged ≥10 they were higher in girls.

CONCLUSIONS

There has been a marked increase in diagnosis of vitamin D deficiency in children over the past decade. Future research should explore the drivers for this change in diagnostic behavior and the reasons prompting investigation of vitamin D status in clinical practice.

High-Dose Monthly Maternal Cholecalciferol Supplementation during Breastfeeding Affects Maternal and Infant Vitamin D Status at 5 Months Postpartum: A Randomized Controlled Trial

BACKGROUND

Many countries recommend daily infant vitamin D supplementation during breastfeeding, but compliance is often poor. A monthly, high-dose maternal regimen may offer an alternative strategy, but its efficacy is unknown.

OBJECTIVE

The objective of the study was to determine the effect of 2 different monthly maternal doses of cholecalciferol on maternal and infant 25-hydroxyvitamin D [25(OH)D] status during the first 5 mo of breastfeeding.

METHODS

With the use of a randomized, double-blind, placebo-controlled design, women who were planning to exclusively breastfeed for 6 mo (n = 90; mean age: 32.1 y; 71% exclusively breastfeeding at week 20) were randomly assigned to receive either cholecalciferol (50,000 or 100,000 IU) or a placebo monthly from week 4 to week 20 postpartum. The treatment effects relative to placebo were estimated as changes in maternal and infant serum 25(OH)D from baseline to week 20 postpartum by using a linear fixed-effects regression model. Additional secondary analyses, adjusted for potential confounders such as season of birth, vitamin D-fortified formula intake, and infant or maternal skin color, were also conducted.

RESULTS

After 16 wk of supplementation, changes in maternal serum 25(OH)D were significantly higher in the 50,000-IU/mo (12.8 nmol/L; 95% CI: 0.4, 25.2 nmol/L) and 100,000-IU/mo (21.5 nmol/L; 95% CI: 9.2, 33.8 nmol/L) groups than in the placebo group (P = 0.43 and P < 0.001, respectively). For infants, the unadjusted mean changes in serum 25(OH)D were 4.5 nmol/L (95% CI: -16.2, 25.0 nmol/L) for the 50,000-IU/mo group and 15.8 nmol/L (95% CI: -4.7, 36.4 nmol/L) for the 100,000-IU/mo group, but the changes did not differ from the placebo reference group. However, after adjustment for season of birth, vitamin D-fortified formula intake, and infant skin color, the mean change effect size for the 100,000-IU/mo group was 19.1 nmol/L (95% CI: 2.5, 35.6 nmol/L; P = 0.025) higher than that in the placebo group.

CONCLUSIONS

Maternal cholecalciferol supplementation at a dose of 100,000 IU/mo during the first 5 mo of breastfeeding potentially benefits infant vitamin D status. Further studies are required to determine optimum dose and dosing frequency. This trial was registered at www.anzctr.org.au as ACTRN12611000108910.

NRAS and EPHB6 mutation rates differ in metastatic melanomas of patients in the North Island versus South Island of New Zealand

Melanoma, the most aggressive skin cancer type, is responsible for 75% of skin cancer related deaths worldwide. Given that New Zealand (NZ) has the world's highest melanoma incidence, we sought to determine the frequency of mutations in NZ melanomas in recurrently mutated genes. NZ melanomas were from localities distributed between North (35°S-42°S) and South Islands (41°S-47°S). A total of 529 melanomas were analyzed for BRAF exon 15 mutations by Sanger sequencing, and also by Sequenom MelaCarta MassARRAY. While, a relatively low incidence of BRAFV600E mutations (23.4%) was observed overall in NZ melanomas, the incidence of NRAS mutations in South Island melanomas was high compared to North Island melanomas (38.3% vs. 21.9%, P=0.0005), and to The Cancer Genome Atlas database (TCGA) (38.3% vs. 22%, P=0.0004). In contrast, the incidence of EPHB6G404S mutations was 0% in South Island melanomas, and was 7.8% in North Island (P=0.0002). Overall, these data suggest that melanomas from geographically different regions in NZ have markedly different mutation frequencies, in particular in the NRAS and EPHB6 genes, when compared to TCGA or other populations. These data have implications for the causation and treatment of malignant melanoma in NZ.