Maternal vitamin D status during pregnancy: the Mediterranean reality

Insights in Nutrition to Optimize Type 1 Diabetes Therapy

Nutrition is an essential part of therapy for type 1 diabetes and is constantly evolving, offering growing opportunities to prevent this disease, slow down its evolution, and mitigate it. An attempt was made to bring together the current state of knowledge. In the path from the preclinical phase of the disease to its clinical onset, there is a phase known as the "honeymoon period" or partial remission, where different possible dietary options for combatting this disease have been presented. The most commonly used dietary models were compared, and the most frequent co-existing pathologies, such as overweight, non-alcoholic fatty liver disease, dyslipidemia, celiac disease, and metabolic instability, were addressed from their nutritional and dietary perspectives to provide clinicians with an updated framework of knowledge and support researchers in further investigations into the topic. Finally, a glimpse into the possible interplay between nutrition and the gut microbiome, food security, and ultra-processed food is provided. It is hoped that clinicians treating people with type 1 diabetes will be provided with further opportunities for the daily management of their patients through personalized nutrition.

Vitamin D and ω-3 Polyunsaturated Fatty Acids towards a Personalized Nutrition of Youth Diabetes: A Narrative Lecture

After the discovery of insulin, nutrition has become central in the management of diabetes in order to limit glycemic rise after meals, optimize metabolic control, and prevent complications. Over the past one hundred years, international scientific societies have consecutively refined nutritional needs and optimized food intake for the treatment of diabetes. In particular, over the past century, nutrition applied with pumps for the administration of insulin and continuous glucose monitoring have allowed substantial advancement in the treatment of type 1 diabetes mellitus. The role of some substances, such as vitamin D and n-3 polyunsaturated fatty acids, have been proposed without univocal conclusions, individually or in combination, or in the diet, to improve the nutrition of type 1 and type 2 diabetes. This second condition, which is highly associated with overweight, should be prevented from childhood onwards. Personalized nutrition could bypass the problem, reaching a scientific conclusion on the individual subject. This article focuses on childhood and adolescent diabetes, aims to provide a narrative summary of nutrition over the past century, and promotes the concept of personalized nutrition to pediatricians and pediatric diabetologists as a possible tool for the treatment of type 1 diabetes and the prevention of type 2 diabetes.

Maternal and Neonatal Vitamin D Binding Protein Polymorphisms and 25-Hydroxyvitamin D Cutoffs as Determinants of Neonatal Birth Anthropometry

Background: Vitamin D-binding protein (VDBP) is a vital regulator of optimal vitamin D homeostasis and bioavailability. Apart from its well-documented role as a key component in vitamin D dynamic transfer and circulation, it has a myriad of immunoregulatory functions related to innate immunity, which becomes particularly critical in states of increased immunological tolerance including pregnancy. In this regard, VDBP dyshomeostasis is considered to contribute to the development of several fetal, maternal, and neonatal adverse outcomes. However, precise physiological pathways, including the contribution of specific VDBP polymorphisms behind such phenomena, are yet to be fully deciphered. Our aim was to assess the combined effect of maternal and neonatal VDBP polymorphism heterogeneity in conjunction with different maternal and neonatal 25(OH)D cutoffs on the neonatal anthropometric profile at birth. Methods: The study included data and samples from a cohort of 66 mother–child pairs at birth. The inclusion criterion was full-term pregnancy (gestational weeks 37–42). Neonatal and maternal 25(OH)D cutoffs were included according to vitamin D status at birth and delivery. Concentrations of 25(OH)D2 and 25(OH)D3 were measured using liquid chromatography–tandem mass spectrometry. Results: The upper arm length of neonates with 25(OH)D ≤ 25 nmol/L was higher in neonate CC carriers for rs2298850. The upper thigh neonatal circumference was also higher in the ones with either 25(OH)D ≤ 50 or ≤75 nmol/L in rs2298850 CG + GG or rs4588 GT + TT carriers. We did not observe any significant effect for maternal VDBP polymorphisms nor for birth maternal 25(OH)D concentrations, on birth neonatal anthropometry. Conclusions: Our findings emphasize a potential role for neonatal VDBP genotypes rs2298850 and rs4588, in conjunction with specific neonatal 25(OH)D cutoffs, in the range of sufficiency on neonatal growth and development.

Could the Majority of the Greek and Cypriot Population Be Vitamin D Deficient?

OBJECTIVE

Hypovitaminosis D is prevalent in epidemic proportions in many developed countries. The aim of this study is to investigate the prevalence of adequate 25-hydroxyvitamin D [25(OH)D] levels in two Mediterranean countries, Greece and Cyprus.

METHODS

Data such as 25(OH)D, the month of blood sample collection, and demographic information were blindly collected from 8780 Greek and 2594 Cypriot individuals over 5 years. Comorbidities were also recorded for 839 Greek subjects. Univariate and multivariate analyses were used to examine the relationship between these variables and 25(OH)D levels.

RESULTS

In the samples studied, 72.7% of the Greek and 69.3% of the Cypriot population sample had inadequate levels of 25(OH)D. The mean level for the Greek subjects was 25.1 ng/mL and for Cypriots 25.8 ng/mL. For both samples, only month and gender were significantly associated with 25(OH)D levels, and the highest mean levels were recorded in September. For the recorded diseases, the lowest levels were recorded in sickle cell anaemia 13.6 ± 10.2 ng/mL, autoimmune diseases 13.0 ± 8.4 ng/mL, and cancer 22.6 ± 9.5 ng/mL.

CONCLUSIONS

The prevalence of vitamin D deficiency is paradoxically high in both Mediterranean countries.

Early pregnancy vitamin D insufficiency and gestational diabetes mellitus

OBJECTIVES

To test the hypothesis that a link existed between vitamin D levels in the first trimester and gestational diabetes mellitus (GDM).

METHODS

The 25-hydroxyvitamin D₃ levels were tested in the first trimester and pregnant outcomes were followed up in 1726 women.

RESULTS

Only 5.9% of pregnant women have sufficient 25(OH)D₃ . More women with GDM are in the status of 25(OH)D₃ insufficiency than women with normal glucose tolerance (NGT) (p < 0.05). Age (odds ratio [OR]: 1.047, 95% confidence interval [CI]: 1.014-1.081), pre-pregnancy body mass index (BMI) (OR: 1.132, 95%CI: 1.092-1.173) were risk factors of GDM while 25-(OH) D₃ (OR: 0.979, 95%CI: 0.960-0.999) was a protective factor. After adjusted for maternal age and pre-pregnancy BMI, 25(OH)D₃ insufficiency (<30 ng/mL) is an independent predictor of GDM (OR: 2.122, 95%CI: 1.084-4.155); 25(OH)D₃ level correlated with fasting blood glucose in the first trimester negatively.

CONCLUSION

Vitamin D insufficiency in early pregnancy was significantly associated with an increased risk for GDM in Chinese women.

Vitamin D Levels in Early and Middle Pregnancy and Preeclampsia, a Systematic Review and Meta-Analysis

Vitamin D (VitD) shows a beneficial role in placentation, the immune system, and angiogenesis, and thus, VitD status may link to the risk of preeclampsia. A meta-analysis was conducted to investigate the association between VitD status in early and middle pregnancy and the risk of preeclampsia. A total of 22 studies with 25,530 participants were included for analysis. Women with VitD insufficiency or deficiency had a higher preeclampsia rate compared to women with replete VitD levels (OR 1.58, 95% CI 1.39–1.79). Women with VitD deficiency had a higher preeclampsia rate compared to women with replete or insufficient VitD levels (OR 1.35, 95% CI 1.10–1.66). Women with insufficient VitD levels had a higher preeclampsia rate compared to women with replete VitD levels (OR 1.44, 95% CI 1.24–1.66). Women with deficient VitD levels had a higher preeclampsia rate compared to women with replete VitD levels (OR 1.50, 95% CI 1.05–2.14). Sensitivity analysis showed the results were stable after excluding any one of the included studies. In conclusion, our systematic review suggested that VitD insufficiency or deficiency was associated with an increased risk of preeclampsia.

Investigating the Role of Functional Polymorphism of Maternal and Neonatal Vitamin D Binding Protein in the Context of 25-Hydroxyvitamin D Cutoffs as Determinants of Maternal-Neonatal Vitamin D Status Profiles in a Sunny Mediterranean Region

Recent results indicate that dysregulation of vitamin D-binding protein (VDBP) could be involved in the development of hypovitaminosis D, and it comprises a risk factor for adverse fetal, maternal and neonatal outcomes. Until recently, there was a paucity of results regarding the effect of maternal and neonatal VDBP polymorphisms on vitamin D status during pregnancy in the Mediterranean region, with a high prevalence of hypovitaminosis D. We aimed to evaluate the combined effect of maternal and neonatal VDBP polymorphisms and different maternal and neonatal 25-hydroxyvitamin D (25(OH)D) cut-offs on maternal and neonatal vitamin D profile. Blood samples were obtained from a cohort of 66 mother–child pairs at birth. Our results revealed that: (i) Maternal VDBP polymorphisms do not affect neonatal vitamin D status at birth, in any given internationally adopted maternal or neonatal cut-off for 25(OH)D concentrations; (ii) neonatal VDBP polymorphisms are not implicated in the regulation of neonatal vitamin D status at birth; (iii) comparing the distributions of maternal VDBP polymorphisms and maternal 25(OH)D concentrations, with cut-offs at birth, revealed that mothers with a CC genotype for rs2298850 and a CC genotype for rs4588 tended to demonstrate higher 25(OH)D (≥75 nmol/L) during delivery (p = 0.05 and p = 0.04, respectively), after adjustments for biofactors that affect vitamin D equilibrium, including UVB, BMI and weeks of gestation. In conclusion, this study from Southern Europe indicates that maternal and neonatal VDBP polymorphisms do not affect neonatal vitamin D status at birth, whereas mothers with CC genotype for rs2298850 and CC genotype for rs4588 demonstrate higher 25(OH)D concentrations. Future larger studies are required to establish a causative effect of these specific polymorphisms in the attainment of an adequate (≥75 nmol/L) maternal vitamin D status during pregnancy.

Vitamin D Fortification of Consumption Cow's Milk: Health, Nutritional and Technological Aspects. A Multidisciplinary Lecture of the Recent Scientific Evidence

Vitamin D is essential in assuring bone health at all stages of life, but its non-skeletal effects are also essential: This vitamin impacts the physiology of the immune system, skeletal muscles and adipose tissue, glucose metabolism, skin, cardiovascular and reproductive systems, neuro-cognitive functions and cell division. The incidence of vitamin D deficiency is widespread worldwide, at any age, in young and healthy subjects, as well as in pregnant women and the elderly population, due to several factors, including inadequate sunlight exposure, skin pigmentation and coverage, adiposity, lifestyle and low dietary intakes. To overcome this problem, the fortification of foods that are consumed on a daily basis, such as milk, is strongly advisable. This opinion paper aims to discuss, in a multidisciplinary way, the current evidence supporting the importance of vitamin D in health and disease and the role of milk as an optimal carrier of this vitamin, to promote adequate intakes, highlighting its unique physico-chemical characteristics linked to both fat globule membrane and casein micelle structure. Moreover, it addresses the impact of industrial processing and storage of consumption milk on the stability of these structures, thus in determining vitamin D bioavailability and the achievement of adequate intakes.

Prevalence and risk factors of hypovitaminosis D in pregnant Spanish women

The hypovitaminosis D epidemic is a global health problem. Our aim was to assess the prevalence and potential risk factors of hypovitaminosis D among pregnant women on the eastern Mediterranean coast. Cross-sectional analysis involved 793 healthy pregnant women (35.3 ± 5.0 years) participating in ECLIPSES, a multicenter randomized trial. Socio-demographic, obstetric, anthropometric, lifestyle, dietary variables and blood draw was collected in the first trimester. Vitamin D deficiency was identified in 50.2% and insufficiency in 30.3% of pregnant women. The mean vitamin D level in the overall sample was 33.9 nmol/L (SD, 17.0). Multivariable logistic regression analysis applying AIC-based backward selection identified excess weight during the 1st trimester (BMI ≥ 25 kg/m²) (OR = 1.950, 95% CI = 1.409, 2.699), Arab ethnic group/dark skin colour (OR = 4.005, 95% CI = 2.488, 6.447), winter/spring (OR = 4.319, 95% CI = 3.112, 5.994), and consumption of milk (OR = 0.754, 95% CI = 0.572, 0.993) and yogurt (OR = 0.635, 95% CI = 0.436, 0.922) as independent risk factors for vitamin D deficiency. All of these factors (except yogurt consumption) and physical activity were independently associated with vitamin D deficiency/insufficiency risk in the final multivariable model (all p < 0.05). All these factors and social class were the most important determinants of circulating 25(OH)D concentrations. Our results confirm a high prevalence of vitamin D deficiency and insufficiency among pregnant women from the eastern Mediterranean coast.

Free and Bioavailable Fractions of Vitamin D: Association with Maternal Characteristics in Brazilian Pregnant Women

Normal pregnancy is characterized by many changes in vitamin D metabolism, challenging the assessment of vitamin D status based exclusively on serum total 25-hydroxyvitamin D (25(OH)D). We hypothesized that measuring free and bioavailable fractions contributes to a better vitamin D status assessment in late pregnancy. Our aim was to evaluate a broad set of biomarkers of vitamin D status in Brazilian women in the third trimester of pregnancy. This cross-sectional study was conducted in women (n = 123, 18-44 y, 27-41 wk gestation) attended in a public maternity in Rio de Janeiro (2016-2018). Biomarkers included serum concentrations of total 25(OH)D3, parathyroid hormone (PTH), vitamin D-binding protein (DBP), and free and bioavailable fractions of 25(OH)D3. Vitamin D insufficiency (<50 nmol/L) was prevalent in 47.9% of the pregnant women. Serum 25(OH)D3 was inversely associated with the gestational week (β = -0.71, 95% confidence interval (CI): -1.31 to -0.16) and season, being lower in autumn (β = -9.90, 95% CI: -16.14 to -3.64) and winter (β = -16.74, 95%CI: -23.13 to -10.34). Concentrations of DBP, and free and bioavailable 25(OH)D3 were also inversely associated with winter months (P < 0.05). DBP was directly associated with prepregnancy BMI (β = 5.84, 95% CI: 0.62 to 11.06). The recognized season-effect on total 25(OH)D3 appeared to also occur on free and bioavailable fractions. Although advanced gestational age was associated with lower total 25(OH)D3, our results suggest an adaptive mechanism responsible for maintaining free fraction during the 3rd trimester. We also suggest that starting pregnancy in obese condition may have an impact on vitamin D bioavailability, which deserves further investigation.

Vitamin D supplementation and fracture risk: Evidence for a U-shaped effect

During the last decade, a cascade of evidence has questioned the anti-fracture efficacy of vitamin D supplementation. In general, vitamin D status, reflected by serum 25-hydroxy-vitamin D [25(OH)D] concentrations, seems to predict fracture risk and bone mineral density (BMD). Despite the well-documented detrimental effect of vitamin D deficiency on bones, vitamin D monotherapy does not seem to reduce the risk of fractures. On the other hand, high vitamin D doses, either at monthly (60,000-100,000 IU) or daily intervals (>4000 IU), appear to be harmful with regard to falls, fracture risk and BMD, especially for people without vitamin D deficiency and at low fracture risk. Therefore, a U-shaped effect of vitamin D on the musculoskeletal system may be supported by the current evidence. Vitamin D supplementation could be of value, at daily doses of at least 800 IU, co-supplemented with calcium (1000-1200  mg/day), in elderly populations, especially those with severe vitamin D deficiency [25(OH)D <25-30  nmol/L (<10-12  ng/mL)], although its anti-fracture and anti-fall efficacy is modest. Good compliance and at least 3-5 years of therapy are required.

Characterizing neonatal vitamin D deficiency in the modern era: A maternal-neonatal birth cohort from Southern Europe

Absence of adequate maternal vitamin D supplementation and decreased maternal ultraviolet exposure during pregnancy are key determinants for the manifestation of neonatal hypovitaminosis D at birth. These parameters may vary, according to country-specific dietary patterns, health policies and sunshine exposure. We aimed to investigate differences in calcium metabolism and anthropometric profiles according to neonatal vitamin D status at birth, in a sunny region of Northern Greece. A secondary aim was to identify maternal parameters as risk factors for developing neonatal vitamin D deficiency at birth. A total of 129 mother-neonate pairs were included in the study and classified into three groups, according to neonatal 25-hydroxy-D [25(OH)D)] concentrations at birth [deficiency (<30 nmol/l), insufficiency (30-50 nmol/l) and sufficiency (>50 nmol/l)]. Neonatal biochemical and anthropometric profiles and maternal demographic, social, dietary and biochemical profiles were comparatively evaluated between the three groups. Univariate and multivariate logistic regression was performed to identify independent associations of maternal factors with neonatal vitamin D status. Vitamin D deficient-neonates manifested higher parathyroid hormone (7.20 ± 2.60 vs 5.50 ± 1.50 pg/ml, p = 0.01) and lower corrected calcium (10.70 ± 0.70 vs 11.30 ± 1.30 mg/dl, p = 0.02) concentrations compared with vitamin d-insufficient neonates. Mothers of vitamin D deficient and insufficient neonates had a lower total of 25(OH)D (31.7 ± 19.2 and 36.5 ± 22.3 vs 53.3 ± 39.0 nmol/l, p < 0.01) and 25(OH)D₃ (27.4 ± 17.5 and 33.3 ± 19.9 vs 47.3 ± 36.7 nmol/l, p < 0.01 and p = 0.04, respectively) concentrations respectively, compared with those of vitamin D-sufficient neonates. Maternal use of alcohol during pregnancy was associated with a 5.57-fold higher risk for neonatal vitamin D deficiency at birth (OR 5.57, 95 % CI1.17-26.56, p = 0.03). Newborns with vitamin D deficiency presented a 6.89-fold higher risk of having been given birth by vitamin D deficient mothers (OR 6.89, 95 % CI 3.09-15.38, p < 0.01). In conclusion, neonatal vitamin D deficiency is associated with maternal 25(OH)D concentrations at birth and maternal alcohol use. Further studies are required to replicate these findings in other regions and populations.

Factors Influencing Vitamin D Levels in Neonatal Umbilical Cord Blood: A Two-Center Study From Tibet and Shenyang

Objective: To investigate the factors influencing the levels of vitamin D (vitD) in the umbilical cord blood of neonates born in Naqu, Tibet (4,500 m above sea level), and Shenyang, Liaoning Province (500 m above sea level). Methods: This prospective study was conducted from June 2017 to October 2018 in Naqu (the plateau group) and Shenyang, (the non-plateau group). Healthy mothers that gave birth to healthy neonates of >2,000g after 38 weeks' gestation were enrolled in the study, as were their neonates. After separation of serum from the umbilical cord and mothers for routine biochemical tests, discarded samples were remained for analyses of vitD, calcium, phosphorus, alkaline phosphatase (ALP) and parathyroid hormone (PTH). Questionnaires were developed covering the demographic characteristics and possible risk factors for neonatal vitD deficiency of mothers. Statistical analysis was performed to identify associations between the calcium, phosphorus, ALP, PTH, maternal factors and neonatal vitD levels. Results: In total, 295 neonates and 225 mothers were enrolled in the study. VitD deficiency was common in neonates and mothers. The risk of vitD deficiency was higher in the plateau group than in the non-plateau group. The mean levels of 25-hydroxy vitD (25(OH)D) in mothers and neonates from the plateau group were 8.49 ± 4.12 ng/mL and 10.17 ± 5.07 ng/mL, respectively. Such levels were significantly lower than those in the non-plateau group (19.77 ± 9.57 ng/mL and 23.93 ± 11.01 ng/mL, respectively). The vitD levels of neonates and mothers were highest in the summer and lowest in the winter. Cord blood vitD was positively correlated with the vitD levels in mothers' serum (r = 0.75, P < 0.05). Increased PTH levels in mothers and decreased cord blood calcium levels were risk factors for neonatal vitD deficiency. A lack of vitD supplementation during pregnancy was associated with an 8.91-fold higher probability of neonatal vitD deficiency (OR = 8.91, 95% CI = 1.521-9.429, P < 0.001). Conclusions: The levels of neonatal and maternal vitD in the plateau group were generally lower than those in the non-plateau group. VitD supplementation during pregnancy could effectively reduce the risk of vitD deficiency in neonates.

Vitamin D and Gestational Diabetes Mellitus: Is There a Link?

Gestational diabetes mellitus (GDM) is a very common condition among pregnant women worldwide with important metabolic implications on the mother and the offspring. Vitamin D status has been suggested to potentially play a role in GDM risk with no documented consequences for the offspring. The purpose of this article was to review currently available evidence on the relationship between vitamin D and GDM. Current evidence shows an association between vitamin D blood levels and risk of GDM, despite heterogeneity of results across studies limit the conclusions. Moreover, data from randomized controlled trials is scarce and resulting in null findings. Among the limitations to be noted, improving the standardization of dosages, the characteristics of individuals in the sample, and the appropriate outcome measurement could provide a more effective approach in understanding the relationship between vitamin D and GDM. In conclusions, despite observational studies may suggest that adequate vitamin D levels may decrease the risk of GDM compared to deficiency status, evidence from clinical trials is inadequate to draft any definitive conclusion regarding its supplementation. Future better designed randomized clinical trials taking into account a more integrated approach could provide clearer and definitive data on the outcomes of such a multifactorial condition.

The prevalence of hypovitaminosis D and its risk factors in pregnant women and their newborns in the Middle East: A systematic review

BACKGROUND

Pregnant women and newborns are at risk for vitamin D deficiency (VDD). Also, poor health outcomes for pregnant women with VDD are reported in the published literature.

OBJECTIVE

The aim of this systematic review was to estimate the prevalence of hypovitaminosis D and the associated risk factors for hypovitaminosis D in Middle Eastern pregnant women and their newborns.

RESULTS

The prevalence of circulating 25-hydroxyvitamin D (25(OH)D) < 50 nmol/L as a marker of vitamin D status in pregnant women and their newborns was between 24.5-98% and 22-100%, respectively. The prevalence of 25(OH) D < 25 nmol/L in pregnant women and their newborns was over a wide range between 16.7-80% and 22-82%, respectively. Predictors for low maternal and neonatal 25(OH)D concentrations included decreased vitamin D synthesis due to reduced exposure to sunlight and decreased nutritional intake of vitamin D. A predictor of low neonatal 25(OH)D concentrations included maternal vitamin D status and the correlation between vitamin D concentrations in maternal and cord blood.

CONCLUSION

The high prevalence of VDD in the pregnant women of the Middle East underscores the necessity of implementing national prevention and intervention strategies. A clear policy for clinicians and healthcare workers is needed for screening and maintaining sufficient vitamin D status during pregnancy.

Vitamin D status in Sudanese pregnant women: a cross-sectional study

Background

Maternal vitamin D deficiency is associated with maternal and perinatal adverse effects. This study was conducted to assess the vitamin D status among pregnant Sudanese women.

Methods

A total of 180 pregnant women were enrolled in a cross-sectional study in Saad Abualila Hospital, Khartoum, Sudan. The medical history of each woman was collected and 25-hydroxyvitamin D [25(OH)D] was measured using an electrochemiluminescence immunoassay.

Results

The median age, gravidity and gestational age was 27.7 y, 1.0 and 10.7 weeks, respectively. Of the 180 woman, 169 (93.9%) had vitamin D deficiency (≤20 ng/ml). There was no correlation between the 25(OH)D level and body mass index (r=−0.135, p=0.071) or haemoglobin level (r= 0.001, p=0.999).

Conclusions

The current study showed a high prevalence of vitamin D deficiency. Further studies investigating the risk factors for vitamin D deficiency and the outcome of pregnancy are needed.

Hypovitaminosis D in Healthy Pregnant Women and their Newborns in Greece

BACKGROUND/OBJECTIVES

The aim of this work was to evaluate the current vitamin D status in healthy pregnant women and their newborns living in Greece and assess possible associations between 25(OH)D and anthropometric features of their fetuses and newborns.

MATERIALS & METHODS

81 healthy women were monitored during pregnancy. Biochemical markers related to bone metabolism, 25(OH)D and PTH levels were measured in serum samples of mothernewborn pairs at 1st trimester of pregnancy and at delivery in mothers, in cord blood and at the 3rd day of life of newborns.

RESULTS

Maternal 25(OH)D levels at the 1st trimester of pregnancy (22.6±9.2ng/ml) were significantly higher than those at delivery (19.2±9.2ng/ml) (p<0.001). Furthermore, umbilical 25(OH)D levels (21.3±9.3ng/ml) were higher than maternal at delivery (p=0.005) and neonatal levels (19.4±10.4 ng/ml) (p=0.021). Only 57.3% of the mothers at the first trimester and 46.7% at delivery as well as 55.8% of the fetuses and 38.5% of the neonates had adequate vitamin D levels (25(OH)D≥30ng/ml). A significant positive correlation was found between fetal femur length at the 22nd week of gestation and maternal 25(ΟΗ)D at the 1st trimester of pregnancy (r=0.36, p=0.048) while body length was significantly higher in newborns whose mothers had sufficient 25(OH)D levels (51.5±2.1cm) compared with those whose mothers had insufficient or deficient 25(OH)D levels at delivery (50.6±2.0cm) (p=0.047).

CONCLUSION

The study confirms inadequate levels of vitamin D in pregnant women in Greece associated with inadequate vitamin D levels of their fetuses and newborns.

Vitamin D Deficiency, Prevalence and Treatment in Neonatal Period

OBJECTIVE

Maternal vitamin D deficiency is an important risk factor that causes infantile rickets in the neonatal and infantile period. The aim of this study was to review the prevalence, clinical characteristics, and treatment of vitamin D deficiency and the follow-ups with infants and their mothers by the neonatal intensive care unit of Afiyet Hospital in Turkey.

METHODS

Calcium (Ca), phosphorus (P) and 25 (OH) vitamin D were studied and prospectively recorded in infants and their mothers detected to have hypocalcemia during routine biochemistry tests performed on the third postnatal day of the patients follow up and treated with different diagnoses.

RESULTS

A total of 2,460 infants were admitted into the neonatal intensive care unit between August 2014 and January 2018. Of the infants included in the study, 324 (66.1%) were male and 166 (33.8%) were female, and 366 (74.6%) of them had been delivered by cesarean section (C/S), 124 (25.3%) of them had been delivered by Normal Spontaneous Delivery (NSD). Hypocalcemia was detected in 490 (19.9%) of the infants. In a total of 190 (38.7%) infants and 86 mothers (17.5%), the levels of 25 (OH) vitamin D were found to be below the laboratory detection limit of <3 ng/ml. When vitamin D deficiency + insufficiency is assessed by season, 151 of them were found to be in summer (30.99%), 118 in spring (24.18%), 117 in the winter season(23.87%), and 93 in autumn(18.97%), respectively. There was a statistically significant positive correlation of 78.7% between the vitamins D values of the mothers and the infants (p: 0.000, p<0.05).

CONCLUSION

This study conducted that a positive correlation of between the vitamin D values of the mothers and the infants. In order to prevent maternal vitamin D deficiency, the appropriate dose of prophylaxis providing optimal levels of vitamin D and should be given by according to the levels of 25 (OH) D vitamin during pregnancy.

An investigation of vitamin D deficiency in pregnant women and their infants in Giresun province located in the Black Sea region of Turkey

The aim of this study is to investigate vitamin D deficiency and the associated risk factors in pregnant women and their infants in the Black Sea region of Turkey. One hundred and twenty healthy pregnant women in the last trimester and their healthy newborn pairs were observed between June and August 2017 in Giresun province. The serum 25(OH)D3 and calcium levels were measured through the samples collected from maternal and neonatal cord blood. The effects of maternal lifestyle on the maternal vitamin D levels were assessed by multiple regression analysis. The mean concentrations of 25(OH)D3 were found to be 9.54 ± 6.35 ng/mL and 11.16 ± 6.52 ng/mL in the maternal and neonatal cord blood sera, respectively. Vitamin D deficiency (≤20 ng/mL) and severe vitamin D deficiency (≤5 ng/mL) were observed in between 94.2% and 24.2% of mothers and 90% and 10% of infants, respectively. The clothing style, the consumption of milk/dairy products and antenatal multivitamin supplement usage were found as significant factors on the serum vitamin D levels. Even during the Summer months, the vitamin D deficiency in mothers and infants was observed at high rates in the Eastern Black Sea region of Turkey. As a result, it has been concluded that routine maternal serum 25(OH)D3 measurements for clinical follow-up, vitamin D supplementation and regular consumption of dairy products should be recommended. Impact Statement What is already known on this subject? Vitamin D deficiency is a very important risk factor to be considered for maternal and infant health. In a large number of studies, it has been observed that the risk of a vitamin D deficiency in women during their pregnancy was found to be higher, depending on the various strong influences such as the demographic and maternal lifestyles. What the results of this study add? A vitamin D deficiency associated with the demographic and lifestyle factors of pregnant women and their infants was investigated in Giresun province, located in the Eastern Black Sea region of Turkey. The results of this study add that a vitamin D deficiency in the maternal and in the infants may be observed at high rates in regions with mostly rainy weather, even during the Summer months. What the implications are of these findings for clinical practice and/or further research? The vitamin D levels in infants can be determined indirectly by looking at the vitamin D levels in third trimester pregnancies. Furthermore, it is suggested as a non-invasive method to determine vitamin D levels by taking advantage of the maternal level, without measuring the vitamin D levels of infants. Thus, this will be effective to reduce health costs and to prevent the possible diseases affecting the future life of infants. Routine maternal serum 25(OH)D3 measurements for clinical follow-up, vitamin D supplementation and the regular consumption of dairy products should be recommended to pregnant women with risk factors, even in the Summer in the Black Sea Region of Turkey. In addition, further studies are needed to investigate the vitamin D deficiency associated with the demographic and lifestyle factors of pregnant women and their infants, especially for the different locations of Turkey.

Maternal type 1collagen N-terminal telopeptide levels in severe hyperemesis gravidarum

Background

Nausea and vomiting occur 50–90% during the first trimester of pregnancy. However, patients with hyperemesis gravidarum (HG) may be hospitalized at an incidence rate of 0.8–2% before the 20th week of gestational age. The symptoms generally start during the 5–6th gestational weeks, reaching the highest degree during the 9th week, and decline after the 16–20th weeks of gestation. Clinical findings are proportional to the severity of the disease and severe HG is characterized with dehydration, electrolyte imbalance, and nutritional deficiency as a result of vomiting.

Methods

The study population consisted of two groups of pregnant volunteers at 5–12 weeks of gestation: a severe HG group and a control group. The HG severity was scored using the Pregnancy-Unique Quantification of Emesis (and nausea) (PUQE).The serum levels of the maternal Ca, parathyroid hormone (PTH), Na, K, blood urea nitrogen(BUN), creatinine, vitamin D(25OHD3), and the maternal urine NTx levels were compared between the groups.

Results

In total, 40 volunteers were enrolled in this study: 20 healthy pregnant volunteers and 20 with severe HG. There were no statistically significant differences between the maternal characteristics. The first trimester weight loss of ≥5 kg was significantly higher in the severe HG group (p < 0.001), while the control group had a significantly higher sunlight exposure ratio than the severe HG group (p = 0.021). The urine NTx levels were significantly higher in the severe HG group (39.22 ± 11.68NTx/Cre) than in the control group(32.89 ± 8.33NTx/Cre) (p = 0.028).The serum Ca, PTH, Na, K, BUN, and creatinine levels were similar between the groups (p = 0.738, p = 0.886, p = 0.841, p = 0.957, p = 0.892, and p = 0.824, respectively). In the severe HG group, the serum 25OHD₃ levels were significantly lower than in the control group (p < 0.001).

Conclusions

The data from this study indicated that severe HG is associated with increased urine NTx levels. However, large-scale studies are required to understand the clinical significance of this finding, as well as the long-term consequences of elevated urine NTx levels and the underlying mechanisms.

Trial registration

NCT02862496 Date of registration: 21/07/2016.

Neonatal hypocalcemia and its relation to vitamin D and calcium supplementation

OBJECTIVES

To assess the prevalence of hypocalcemia in outpatient clinic neonates and its relation to vitamin D and calcium supplementation.  Methods: This cross-sectional analytical study was conducted at the University Teaching Hospital from May to October 2016. Data were collected from 100 neonates by interviewing mothers using a structured questionnaire; which included socio-demographic information, maternal and neonatal history; in addition to investigations of serum calcium total and ionized and serum vitamin D level. Results: The prevalence of hypocalcemia was 76%, late hypocalcemia represent 52% of hypocalcemic neonates. The prevalence of hypovitaminosis D was 38%. Hypocalcemia was found more prevalent among neonates with no history of vitamin D supplementation (98.7%), no history of maternal calcium supplementation (57.9%), while they had a history of neonatal jaundice on phototherapy (46.1%) which increased to 53.8% with late hypocalcemia. Conclusion: Neonatal hypocalcemia is widely prevalent in Fayoum governorate with significant association with a history of neonatal jaundice on phototherapy, not receiving maternal calcium or neonatal vitamin D supplementation.

Low maternal vitamin D status in pregnancy increases the risk of childhood obesity

BACKGROUND

Vitamin D may modulate adipogenesis. However, limited studies have investigated the effect of maternal vitamin D during pregnancy on offspring adiposity or cardiometabolic parameters with inconclusive results.

OBJECTIVES

The objective of this study is to examine the association of maternal 25(OH)-vitamin D [25(OH)D] status with offspring obesity and cardiometabolic characteristics in 532 mother-child pairs from the prospective pregnancy cohort Rhea in Crete, Greece.

METHODS

Maternal 25(OH)D concentrations were measured at the first prenatal visit (mean: 14 weeks, SD: 4). Child outcomes included body mass index standard deviation score, waist circumference, skin-fold thickness, blood pressure and serum lipids at ages 4 and 6 years. Body fat percentage was also measured at 6 years. Body mass index growth trajectories from birth to 6 years were estimated by mixed effects models with fractional polynomials of age. Adjusted associations were obtained via multivariable linear regression analyses.

RESULTS

About two-thirds of participating mothers had 25(OH)D concentrations <50 nmol L^-1 . Offspring of women in the low 25(OH)D tertile (<37.7 nmol L^-1 ) had higher body mass index standard deviation score (β 0.20, 95% CI: 0.03, 0.37), and waist circumference (β 0.87 95% CI: 0.12, 1.63) at preschool age, compared with the offspring of women with higher 25(OH)D measurements (≥37.7 nmol L^-1 ), on covariate-adjusted analyses. The observed relationships persisted at age 6 years. We found no association between maternal 25(OH)D concentrations and offspring blood pressure or serum lipids at both time points.

CONCLUSIONS

Exposure to very low 25(OH)D concentrations in utero may increase childhood adiposity indices. Given that vitamin D is a modifiable risk factor, our findings may have important public health implications.

Christian Orthodox fasting in practice: A comparative evaluation between Greek Orthodox general population fasters and Athonian monks

OBJECTIVES

Christian Orthodox fasting (COF), a periodical vegetarian subset of the Mediterranean diet, has been proven to exert beneficial effects on human health. Athonian fasting is a pescetarian COF variation, where red meat is strictly restricted throughout the year. Previous studies have examined the COF nutritional synthesis and health effects in general population fasters (GF) and Athonian monks (AM), separately. The aim of this study is to comparatively evaluate the characteristics and effects of this nutritional advocacy between the two populations.

METHODS

The study included 43 male GFs (20-45 y of age) and 57 age-matched male AMs following COF. Dietary intake data were collected in both groups during a restrictive (RD) and a nonrestrictive (NRD) day. Nutritional, cardiometabolic, and anthropometric parameters were compared between the two cohorts.

RESULTS

AM presented lower daily total caloric intake for both RD (1362.42 ± 84.52 versus 1575.47 ± 285.96 kcal, P < 0.001) and NRD (1571.55 ± 81.07 versus 2137.80 ± 470.84 kcal, P < 0.001) than GF.They also demonstrated lower body mass index (23.77 ± 3.91 versus 28.92 ± 4.50 kg/m², P <0.001), body fat mass (14.57 ± 8.98 versus 24.61 ± 11.18 kg, P = 0.001), and homeostatic model assessment for insulin resistance values (0.98 ± 0.72 versus 2.67 ± 2.19 mmol/L, P < .001) than GF. Secondary hyperparathyroidism (parathyroid hormone concentrations: 116.08 ± 49.74 pg/mL), as a result of profound hypovitaminosis D [25(OH)D: 9.27 ± 5.81 ng/mL], was evident in the AM group.

CONCLUSIONS

The results of the present study highlight the unique characteristics of Athonian fasting and its value as a health-promoting diet. The effects of limitation of specific vitamins and minerals during fasting warrants further investigation.

Thyroid Function and 25 (OH) Vitamin D Level among Sudanese Women in Early Pregnancy

AIM:

A cross-sectional study was conducted at Saad Abualila Hospital (Khartoum, Sudan) to evaluate the vitamin D levels and thyroid function among pregnant Sudanese women (132) in early pregnancy.

METHODS:

A cross-sectional study was conducted at Saad Abualila hospital (Khartoum, Sudan) during the period from March to July 2015. Women who were in early pregnancy with a singleton pregnancy were approached to participate in the study after signing informed consent. A sample size of 132 participants was calculated guided by the normal interval of thyroid function in Sudanese women in the first trimester and not the level of 25(OH) vitamin D. The 25 - hydroxyvitamin D (25 (OH) vitamins levels were measured using an electrochemiluminescence immunoassay on an Elecsys 2010 Analyzer (Roche Diagnostics, Mannheim, Germany).

RESULTS:

The mean (SD) of age, gravidity and gestational age was 27.6 (5.5) years, 2.2 (1.6) and 10.4 (2.2) weeks, respectively. The mean (SD) of the body mass index (BMI) and haemoglobin was 27.1 (5.2) kg/m² and 10.8 (1.1) g/dl, respectively. Median (interquartile) values of TSH, FT3, and FT4 were 1.164 IU/ml (0.079 -2.177 IU/ml), 4.639 nmol/l (3.843 - 6.562 nmol/l), and 16.86 pmol/l (13.02 - 31.48 pmol/l), respectively. There was no significant correlation between vitamin D levels and TSH, FT3 and FT4

CONCLUSION:

There is no correlation between 25 (OH) vitamin D levels and thyroid function during early pregnancy among Sudanese pregnant women, despite prevalent vitamin D deficiency among these women.

High maternal vitamin D levels in early pregnancy may protect against behavioral difficulties at preschool age: the Rhea mother-child cohort, Crete, Greece

Animal studies suggest that prenatal vitamin D status may affect fetal brain growth. However, human studies are scarce with conflicting results. We aimed to investigate the association of maternal 25-hydroxyvitamin D [25(OH) D] levels with multiple neurodevelopmental outcomes at 4 years of age. We included 487 mother-child pairs from the prospective pregnancy cohort, "Rhea" in Crete, Greece. Maternal serum 25(OH) D concentrations were measured at the first prenatal visit (13 ± 2.4 weeks). Cognitive functions at 4 years were assessed by means of the McCarthy Scales of Children's Abilities. Behavioral difficulties were assessed by means of Strengths and Difficulties Questionnaire and Attention Deficit Hyperactivity Disorder Test. Children of women in the high 25(OH) D tertile (>50.7 nmol/l) had 37% decreased number of hyperactivity-impulsivity symptoms (IRR 0.63, 95% CI 0.39, 0.99, p _trend = 0.05) and 40% decreased number of total ADHD-like symptoms (IRR 0.60, 95% CI 0.37, 0.95, p _trend = 0.03) at 4 years of age, compared to children of women in the low 25(OH) D tertile (<38.4 nmol/l), after adjustment for several confounders. Similar associations were found with the hyperactivity/inattention score of the SDQ questionnaire. Children of mothers with high 25(OH) D levels had also fewer total behavioral difficulties (beta-coeff: -1.25, 95% CI -2.32, -0.19) and externalizing symptoms (beta-coeff: -0.87, 95% CI -1.58, -0.15) at preschool age. The observed associations were stronger in girls than in boys (p _{for interaction} < 0.1). No association was observed between maternal 25(OH) D concentrations and cognitive function in preschoolers. Our results suggest that high maternal vitamin D levels in early pregnancy may protect against behavioral difficulties, especially ADHD-like symptoms at preschool age.

Deconvoluting the Biological Roles of Vitamin D-Binding Protein During Pregnancy: A Both Clinical and Theoretical Challenge

The teleological purpose of an ongoing pregnancy is to fulfill its fundamental role of a successful, uncomplicated delivery, in conjunction with an optimal intrauterine environment for the developing fetus. Vitamin D metabolism is adapted to meet both these demands during pregnancy; first by stimulation of calcium absorption for adequate intrauterine bone mineral accrual of the fetus, and second, by enhancing systemic and local maternal tolerance to paternal and fetal alloantigens. Vitamin D-binding protein (VDBP) is one of the key biomolecules that optimize vitamin D homeostasis and also contributes as an immune regulator for a healthy, ongoing pregnancy. In this regard, recent results indicate that dysregulation of VDBP equilibrium could be a risk factor for adverse fetal, maternal, and neonatal outcomes, including preeclampsia, preterm birth, and gestational diabetes. Moreover, it has been hypothesized to be also implicated in the interpretation of vitamin D status in the pregnant state. The aim of this review is to assess available literature regarding the association of VDBP with clinical outcomes during pregnancy, as a potential biomarker for future clinical practice, with a discourse on current knowledge gaps and future research agenda.

Adiponectin and vitamin D-binding protein are independently associated at birth in both mothers and neonates

CONTEXT

Adult body fat is associated with birth anthropometry, suggesting a role for metabolic regulators including vitamin D and the adipokines-adiponectin and irisin-which have been reported to interact but, as yet, data remain controversial.

OBJECTIVE

To study (i) the relationship between vitamin D, its binding protein (VDBP) and the adipokines, adiponectin, and irisin in mothers and neonates at birth and (ii) their effects on neonate anthropometric outcomes.

DESIGN

Cross-sectional study for healthy mothers with full-term and uncomplicated births.

SETTING

Primary care.

SUBJECTS

Seventy pairs of newly delivered neonates and their mothers.

MAIN OUTCOMES FEATURES

Biochemical markers from maternal and cord: VDBP, adiponectin, irisin, calcium, albumin, parathyroid hormone, 25OHD, 1,25(OH)₂D. Maternal demographic and social characteristics and neonate anthropometric parameters were recorded.

RESULTS

Maternal VDBP levels (364.1 ± 11.9 μg/ml) demonstrated a strong positive correlation with maternal adiponectin (4.4 ± 0.4 μg/ml) and irisin (308.8 ± 50.8 ng/ml) concentrations, which remained significant (p < 0.001 and p < 0.041, respectively) after adjustment with multiple parameters, including weeks of gestation, maternal age, and BMI. The finding of a strong association of VDBP (355.3 ± 29.2 μg/ml) and adiponectin (11.9 ± 2.0 μg/ml) but not irisin (174.4 ± 26.0 ng/ml) was also evident in neonates (p = 0.03 and p = 0.94, respectively). No association was observed in both maternal and neonatal vitamin D, adiponectin, and irisin.

CONCLUSIONS

The main findings of this study are (i) the perspective of a potential independent interaction of VDBP and adiponectin in both mothers and neonates and (ii) the lack of a causative model effect of both maternal/neonatal vitamin D status and adipokine profile on neonatal anthropometry at birth, as a surrogate marker of future metabolic health of the offspring.

Vitamin D Concentration in Maternal and Umbilical Cord Blood by Season

Summer is generally considered to be the season when the body is well-supplied with vitamin D. The aim of this study was to compare maternal and umbilical cord blood concentrations of vitamin D during two extreme seasons of the year in Poland-winter and summer. A total of 100 pregnant women with no history of chronic diseases before pregnancy were included in the study. Pre-delivery maternal venous blood and neonatal cord blood samples were collected and total 25(OH)D concentration was measured. Data on vitamin D consumption (collected with the use of Food Frequency Questionnaire) and lifestyle factors were taken. Both, maternal and umbilical cord blood concentrations of vitamin D were higher in the summer group as compared to the winter group (mean 22.2 ± 6.5 ng/mL vs. 16.5 ± 8.2 ng/mL (p < 0.001), respectively for the mothers and 31.3 ± 9.4 ng/mL vs. 22.7 ± 11.0 ng/mL (p < 0.0001), respectively for the neonates). However, only 16% of the pregnant women reached the optimal vitamin D concentration during summer. Therefore, summer improves the levels of vitamin D in the body but does not guarantee the recommended concentration and supplementation throughout the whole year is essential.

Meta-analysis of the effect of the maternal vitamin D level on the risk of spontaneous pregnancy loss

BACKGROUND

The association between vitamin D deficiency and early spontaneous pregnancy loss (SPL) is unclear.

OBJECTIVES

To assess the association of serum 25-hydroxyvitamin D (25(OH)D) and SPL.

SEARCH STRATEGY

Embase, PubMed, and Web of Science were searched for relevant papers published before February 20, 2016, using search terms including "vitamin D" and "pregnancy loss."

SELECTION CRITERIA

Case-control and cohort studies investigating the relationship of maternal serum 25(OH)D and SPL were included.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted original data from the selected papers. The DerSimonian-Laird random-effects model was used to perform the meta-analysis. Heterogeneity was assessed by calculating I² .

MAIN RESULTS

Five studies, including 10 630 pregnant women, met the inclusion criteria. There was no significant association between a low 25(OH)D level and an increased risk of SPL. In a subgroup analysis, an extremely low 25(OH)D level (<20 ng/mL) was significantly associated with an increased risk of SPL in the first trimester (relative risk 2.24, 95% confidence interval 1.15-4.37); the heterogeneity across studies was not significant (I² =0.0%, P=0.355).

CONCLUSIONS

Severe Vitamin D deficiency could be detrimental to early embryonic development and increase the risk of early SPL.

Health benefits and consequences of the Eastern Orthodox fasting in monks of Mount Athos: a cross-sectional study

BACKGROUND/OBJECTIVES

Greek Orthodox fasting (OF), which involves 180-200 days of fasting per year, is dictated by the Christian Orthodox religion. For the first time, this cross-sectional study examines the characteristics and the effects of OF on anthropometry, cardiometabolic markers and calcium homeostasis in Athonian monks (AMs).

SUBJECTS/METHODS

Daily intakes of energy, macro- and micronutrients of a day during a weekend of Nativity Fast, defined as non-restrictive day (NRD), and a weekday during Great Lent, labeled as restrictive day (RD) were recorded.

RESULTS

The daily energy intake of 70 AM (age=38.8±9.7 years) was low during both RD and NRD (1265.9±84.5 vs 1660±81 kcal, respectively, P<0.001). Paired samples t-test showed statistically significant difference between daily intakes in RD and NRD: carbohydrates (159.6±21.8 vs 294.3±23.4 g, P<0.0001) and saturated fat (12.7±0.0 vs 16.4±0.0 g, P<0.0001) were lower, whereas protein (89.2±1.3 vs 72.35±1.3 g, P<0.001) was higher during RD. A subsample of 50 monks (age=38.7±10.6 years) formed a study cohort for cardiometabolic and calcium homeostasis assessment. Body weight (74.3±12.9 kg) and body mass index (BMI; 23.8±4.1 kg/m2) were independent of level of physical activity. Optimal profiles for lipid and glucose parameters (total cholesterol: 183.4±41.7 mg/dl, LDL: 120.6±37.6 mg/dl, triglycerides: 72.2±31.3 mg/dl, HDL: 48.5±14.2 mg/dl and homeostasis model assessment of insulin resistance (HOMA-IR) 1.02±0.40) were found. Profound hypovitaminosis D (8.8±6.2 ng/ml), high parathyroid hormone (PTH): 115.5±48.0 pg/ml with normal serum calcium levels (8.9±3.2 mg/dl) was observed.

CONCLUSIONS

Unaffected by variation in lifestyle factors, the results of this unique study offers clear evidence for the health benefits of the strict Athonian OF through optimal lipid and glucose homeostasis.

Vitamin D status correction in Saudi Arabia: an experts' consensus under the auspices of the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis, and Musculoskeletal Diseases (ESCEO)

BACKGROUND

Vitamin D deficiency is common in the Middle East and in Saudi Arabia, in particular. While several international recommendations on the management of vitamin D deficiency have been documented and practiced globally, these recommendations should be adapted to the conditions of the Middle Eastern region. To address this challenge, the Prince Mutaib Chair for Biomarkers of Osteoporosis (PMCO) in King Saud University (KSU), Riyadh, KSA, together with local experts and in cooperation with the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis (ESCEO), organized a panel that formulated unified recommendations in the diagnosis and treatment of vitamin D deficiency in the region.

METHODS

The selection of local and international experts commenced during the 2nd International Vitamin D Symposium conducted in Riyadh, Saudi Arabia, last January 20--21, 2016. Reviews of the most recent literature were done, and face-to-face meetings were conducted for revisions and final recommendations.

RESULTS

Vitamin D sufficiency is defined as circulating serum 25(OH)D ≥50 nmol (≥20 ng/ml) for the general population and vitamin D adequacy as serum 25(OH)D >75 nmol/L l (>30 ng/ml) for the frail and osteoporotic elderly. Despite overwhelming prevalence of vitamin D deficiency, universal screening is not recommended. Recommendations for the general population, children, pregnant/lactating women, post-menopausal women, the elderly, and those with subsequent metabolic diseases were provided.

RESULTS

Vitamin D sufficiency is defined as circulating serum 25(OH)D ≥50 nmol (≥20 ng/ml) for the general population and vitamin D adequacy as serum 25(OH)D >75 nmol/L l (>30 ng/ml) for the frail and osteoporotic elderly. Despite overwhelming prevalence of vitamin D deficiency, universal screening is not recommended. Recommendations for the general population, children, pregnant/lactating women, post-menopausal women, the elderly, and those with subsequent metabolic diseases were provided.

CONCLUSION

Vitamin D supplementation/correction is advised in all persons whose serum 25(OH)D falls below 50 nmol/l (20 ng/ml), and achieving a target of 75 nmol/l (30 ng/ml) is particularly suited for frail, osteoporotic, and older patients. Conducting well-designed clinical trials in the region that will address economic implications and investigations on the treatment persistence and compliance to vitamin D treatment in the region are encouraged.

Better Body Composition and Lipid Profile Can Be Associated with Vitamin D Status in Spanish Elderly? The PHYSMED Study

Studies have shown that vitamin D deficiency increases the risk for lipid metabolism disorders, but this relationship has provided inconsistent results in elderly. Thus the aim was to assess the association between body composition and blood lipid profile levels on serum 25-hydrovitamin D [25(OH)D] concentration in Spanish elderly. A cross-sectional multicentre study was carried out in 383 participants (58.2% females) aged of 55-88 years. Fasting blood samples analyzed serum concentrations of 25(OH)D, low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides (TG) and total cholesterol (TC). Body composition parameters (fat mass, fat free mass) were obtained by bioimpedance, waist circumference (WC), physical activity and vitamin D intake were also evaluated. BMI, fat mass and total fat mass were lower in vitamin D sufficient subjects than vitamin D insufficient and deficient subjects, but this difference was not significant (p>0,05). Those with vitamin D adequate levels also showed lower TC/HDL ratio than those who had inadequate (insufficient or deficient) vitamin D levels (p=0.04). Significant association between 25(OH)D and BMI, waist circumference, total muscle mass, TC/HDL-c ratio, HDL and TG (for all p≤ 0.05) was found after controlling for some confounders. Subjects with inadequate HDL levels (<40mg/dL) showed 1.7 times higher odds than vitamin D deficiency than those with adequate HDL levels (>60mg/dL) (95% CI= 1.10 to 2.85 p= 0.017) and WC was negatively associated with vitamin D status odds ratio of 0.98 (0.96 to 1.00; p= 0.04). Vitamin D concentration was positively correlated with HDL-c and total muscle mass, as well as negatively correlated with WC, LDL-c/HDL-c and TC/HDL-c independently of age, gender and some confounders.

Maternal Vitamin D Status and Adverse Birth Outcomes in Children from Rural Western Kenya

Maternal plasma 25-hydroxyvitamin D (25(OH)D) status and its association with pregnancy outcomes in malaria holoendemic regions of sub-Saharan Africa is poorly defined. We examined this association and any potential interaction with malaria and helminth infections in an ongoing pregnancy cohort study in Kenya. The association of maternal plasma 25(OH)D status with pregnancy outcomes and infant anthropometric measurements at birth was determined in a subset of women (n = 63). Binomial and linear regression analyses were used to examine associations between maternal plasma 25(OH)D and adverse pregnancy outcomes. Fifty-one percent of the women had insufficient (<75 nmol/L) and 21% had deficient (<50 nmol/L) plasma 25(OH)D concentration at enrollment. At birth, 74.4% of the infants had insufficient and 30% had deficient plasma 25(OH)D concentrations, measured in cord blood. Multivariate analysis controlling for maternal age and body mass index (BMI) at enrollment and gestational age at delivery found that deficient plasma 25(OH)D levels were associated with a four-fold higher risk of stunting in neonates (p = 0.04). These findings add to the existing literature about vitamin D and its association with linear growth in resource-limited settings, though randomized clinical trials are needed to establish causation.

Maternal serum vitamin D levels and pregnancy outcomes: from Lagos, Nigeria

In an attempt to investigate the effect of vitamin D deficiency on pregnancy complications including caesarean section and foetal outcome in our population, blood samples of 461 pregnant women who attended antenatal booking clinic between 10 and 28 weeks of pregnancy were taken for vitamin D estimation and followed up. Details concerning pregnancy complications, labour and foetal outcome were obtained after delivery. They were divided into three groups according to the serum vitamin D level: group 1 (0-20)ng/ml (deficiency), group 2 (21-30)ng/ml (insufficiency), and group 3 (more than 30 mg/ml) normal. The prevalence of vitamin D deficiency was 29%. There were no differences between the groups regarding complications during pregnancy, including preeclampsia and rate of caesarean section. A multicenter study was advocated to elucidate further the role of vitamin D during pregnancy in our population.

Effects of maternal genetic polymorphisms in vitamin D-binding protein and serum 25-hydroxyvitamin D concentration on infant birth weight

OBJECTIVE

Vitamin D deficiency is a common problem during pregnancy and might contribute to adverse birth outcomes. Vitamin D-binding protein plays a key role in regulating vitamin D metabolism. We investigated whether maternal genetic variation in GC, the gene encoding vitamin-D binding protein, modulates the relationship between 25-hydroxyvitamin D [25(OH)D] levels and infant birth weight.

METHODS

We measured 25(OH)D concentrations in maternal and umbilical cord blood from 356 pregnant women and their infants by liquid chromatography tandem mass spectrometry. We extracted DNA from the maternal blood for genotyping GC single-nucleotide polymorphisms (SNPs).

RESULTS

The 25(OH)D concentrations were significantly higher in the maternal blood than in the cord blood, although the concentrations from each source were positively correlated with one another among individuals. Maternal GC SNPs rs12512631 and rs7041 were not significantly associated with infant birth weight. On the other hand, the GC SNPs rs12512631 and rs7041 significantly modified the relationships between the maternal and cord-blood concentrations of 25(OH)D and birth weight. Low 25(OH)D levels in the maternal and cord blood were significantly associated with decreased birth weight among infants born to mothers carrying the rs12512631 'C' allele but not in those born to mothers homozygous for the 'T' allele (P-interaction = 0.043 and 0.0008 for the maternal and cord blood, respectively). Low 25(OH)D levels in the cord blood were significantly associated with decreased birth weight only among infants born to mothers carrying the rs7041 'G' allele (P-interaction = 0.009).

CONCLUSIONS

Our findings suggest that the interaction between 25(OH)D status and some maternal GC variants influence the birth weight of infants.

Maternal vitamin D levels during pregnancy and neonatal health: evidence to date and clinical implications

Low maternal vitamin D levels during pregnancy have been associated with a plethora of adverse neonatal outcomes, including small for gestational age and preterm births, detrimental effect on offspring bone and teeth development, and risk of infectious diseases. Although most observational studies indicate a significant linear relationship between maternal 25-hydroxyvitamin D and the above outcomes, some randomized controlled trials to date are inconclusive, mostly due to differences in study design and supplementation regimen. The currently available results indicate that vitamin D supplementation during pregnancy reduces the risk of preterm birth, low birth weight, dental caries of infancy, and neonatal infectious diseases such as respiratory infections and sepsis. This narrative review aims to summarize available trial results regarding the effect of low maternal vitamin D levels during pregnancy, in conjunction with neonatal outcomes on the field, with a discourse on the appropriate clinical approach of this important issue.

Vitamin D in Fibromyalgia: A Causative or Confounding Biological Interplay?

Fibromyalgia (FM) is a chronic syndrome with an increasing prevalence, characterized by widespread musculoskeletal pain in combination with a variety of cognitive symptoms and fatigue. A plethora of scientific evidence that has accumulated during the last decades, resulted in a significant improvement of the understanding of the pathophysiology of the disease. However, current therapeutic approaches in patients with FM remains a multidimensional approach including patient education, behavioral therapy, exercise, pain management, and relief of chronic symptoms, rather than the use drug therapies, based on the mechanisms of disease development. Vitamin D, a fat-soluble vitamin derived mainly from skin synthesis through ultraviolet radiation, has been recognized to manifest a plethora of extraskeletal actions, apart from its fundamental role in skeletal and calcium homeostasis, including modulation of cell growth, neuromuscular actions, and potential anti-inflammatory properties. Recent findings indicate that hypovitaminosis D to be highly prevalent in patients with FM. Supplementation studies are limited so far, indicating potential beneficial effects on pain and severity of the disease, however specific recommendations are lacking. This review aims to summarize and critically appraise data regarding the pathophysiological interplay between vitamin D and FM, available results from observational and supplementation studies so far, with a clinical discourse on current knowledge gaps and future research agenda.

Impact of vitamin D deficiency on maternal and birth outcomes in the Saudi population: a cross-sectional study

Background

Low serum vitamin D [25(OH)D] has been associated with different health problems worldwide. However, its causal role in several diseases remains unclear. We aimed to correlate vitamin D status with maternal and neonatal outcomes in pregnant females.

Method

One thousand pregnant women were recruited during early labour from the labour ward of King Khaled University Hospital, Riyadh, Saudi Arabia. Detailed medical data of all participants were collected from their records. Delivery events and birth outcomes were also documented. Serum 25(OH)D levels were measured using an enzyme-linked immunosorbent assay. A receiver operating characteristic (ROC) curve was constructed to evaluate the ability of vitamin D levels to predict complicated pregnancies. Regression analysis was used to test the correlation between serum 25(OH)D levels and different variables.

Results

Most of the participants were Saudis (89.9 %) and housewives (85.1 %) and 86.4 % of them had vitamin D deficiency (mean: 30.46 ± 19.6 nmol/L). Gestational diabetes mellitus (GDM) was the commonest complication detected (11.1 %) while the history of miscarriage was elevated (24.5 %). There was no association between GDM and low 25(OH)D. Yet, there was a significant negative correlation between serum 25(OH)D levels and fasting blood glucose among females older than 35 years (r = −0.2, p = 0.03). Hypertensive disorders of pregnancy and pre-existing hypertension were less than 1.5 % of frequency. Nevertheless, they were only recorded in women with insufficient and deficient vitamin D. ROC curve revealed that 25(OH)D levels were not able to discriminate between normal and adverse pregnancy outcomes (AUROC curve: 0.51; 95 % confidence interval (CI): 0.44–0.58; p = 0.8).

Conclusion

Hypovitaminosis D, a highly prevalent health problem among pregnant females in Riyadh, has no relation to adverse pregnancy outcomes except for a higher prevalence of miscarriage in women with low 25(OH)D.

Electronic supplementary material

The online version of this article (doi:10.1186/s12884-016-0901-4) contains supplementary material, which is available to authorized users.

Association Between High Ambient Temperature and Risk of Stillbirth in California

Recent studies have linked elevated apparent temperatures with adverse birth outcomes, such as preterm delivery, but other birth outcomes have not been well studied. We examined 8,510 fetal deaths (≥20 weeks' gestation) to estimate their association with mean apparent temperature, a combination of temperature and humidity, during the warm season in California (May-October) from 1999 to 2009. Mothers whose residential zip codes were within 10 km of a meteorological monitor were included. Meteorological data were provided by the California Irrigation Management Information System, the US Environmental Protection Agency, and the National Climatic Data Center, while the California Department of Public Health provided stillbirth data. Using a time-stratified case-crossover study design, we found a 10.4% change (95% confidence interval: 4.4, 16.8) in risk of stillbirth for every 10°F (5.6°C) increase in apparent temperature (cumulative average of lags 2-6 days). Risk varied by maternal race/ethnicity and was greater for younger mothers, less educated mothers, and male fetuses. The highest risks were observed during gestational weeks 20-25 and 31-33. No associations were found during the cold season (November-April), and the observed associations were independent of air pollutants. This study adds to the growing body of literature identifying pregnant women and their fetuses as subgroups vulnerable to heat exposure.

The persistence of maternal vitamin D deficiency and insufficiency during pregnancy and lactation irrespective of season and supplementation

BACKGROUND

Pregnancy and lactation comprise a critical window spanning all seasons during which maternal vitamin D status potentially may influence the long-term health of the newborn. Women typically receive calcium/vitamin D supplementation through antenatal vitamins, but there has been limited serial evaluation of maternal vitamin D status across this critical window.

DESIGN/PATIENTS/MEASUREMENTS

In this prospective observational cohort study, 467 women in Toronto, Canada, underwent measurement of serum 25-hydroxy vitamin D (25-OH-D) at mean 29·7 ± 2·9 weeks' gestation, 3 months postpartum and 12 months postpartum, enabling serial assessment across 3 seasons. At each assessment, vitamin D status was classified as deficiency (25-OH-D<50 nmol/l), insufficiency (25-OH-D≥50 nmol/l and <75 nmol/l) or sufficiency (25-OH-D≥75 nmol/l).

RESULTS

The prevalence rates of vitamin D deficiency and insufficiency were 31·5% and 35·1% in pregnancy, 33·4% and 35·3% at 3 months, and 35·6% and 33·8% at 12 months postpartum, respectively. These high rates remained stable over time (P = 0·49) despite declining usage of antenatal calcium/vitamin D supplementation from pregnancy to 3 months to 12 months postpartum (P < 0·001). Indeed, on mixed model analyses, vitamin D deficiency and insufficiency in pregnancy were independently associated with decrements in average 25-OH-D over time of 49·6 nmol/l and 26·4 nmol/l, respectively (both P < 0·001). In contrast, season of baseline assessment and use of calcium/vitamin D supplements were independently associated with changes in 25-OH-D in the range of 3-5 nmol/l (both P < 0·008).

CONCLUSIONS

The persistence of vitamin D deficiency/insufficiency during pregnancy and lactation, irrespective of season and supplementation, supports the emerging concept that current vitamin D supplementation in antenatal care is likely inadequate.

Vitamin D Status in Pregnancy and Determinants in a Southern European Cohort Study

BACKGROUND

Population-based data on vitamin D status in pregnancy in southern European countries are scarce. We assessed the prevalence and determinants of vitamin D insufficiency and deficiency in pregnancy in Spain.

METHODS

Plasma 25-hydroxyvitamin D3 (25(OH)D3) concentration was measured at the first trimester of gestation in 2,036 pregnant women from several geographical areas of Spain (latitude 39-42°N). Uni- and multivariable regression models were conducted to identify predictors of circulating 25(OH)D3 concentration and vitamin D insufficiency (20-30 ng/mL) and deficiency (<20 ng/mL).

RESULTS

Thirty-one per cent and 18% of women were vitamin D insufficient and deficient, respectively. Season at blood collection, latitude, age, social class, tobacco smoking, physical activity and use of vitamin D supplements were identified as independent determinants of 25(OH)D3 concentration. Lower risk of vitamin D insufficiency and deficiency was associated with summer season at blood collection (RR for insufficiency = 0.34, confidence intervals (CI) 0.25, 0.48; and RR for deficiency = 0.07, 95% CI 0.04, 0.12), southern latitude (RR for insufficiency = 0.71, 95% CI 0.50, 1.02; RR for deficiency = 0.60, 95% CI 0.38, 0.94); use of vitamin D supplements (RR for insufficiency = 0.50, 95% CI 0.35, 0.71; RR for deficiency = 0.24, 95% CI 0.14, 0.41); and strong physical activity (RR for insufficiency = 0.80, 95% CI 0.58, 1.09; and RR for deficiency = 0.67, 95% CI 0.46, 1.03). Higher risk of vitamin D deficiency was related to lower social class (RR = 1.94, 95% CI 1.19, 3.16) and smoking (RR = 1.76, 95% CI 1.23, 2.54).

CONCLUSIONS

Vitamin D insufficiency and deficiency are highly prevalent in pregnancy. Recommendations and policies to detect and prevent hypovitaminosis D during pregnancy should be developed taking into account the associated factors.

Micronutrient deficiencies in pregnancy worldwide: health effects and prevention

Micronutrients, vitamins and minerals accessible from the diet, are essential for biologic activity. Micronutrient status varies widely throughout pregnancy and across populations. Women in low-income countries often enter pregnancy malnourished, and the demands of gestation can exacerbate micronutrient deficiencies with health consequences for the fetus. Examples of efficacious single micronutrient interventions include folic acid to prevent neural tube defects, iodine to prevent cretinism, zinc to reduce risk of preterm birth, and iron to reduce the risk of low birth weight. Folic acid and vitamin D might also increase birth weight. While extensive mechanistic and association research links multiple antenatal micronutrients with plausible materno-fetal health advantages, hypothesized benefits have often been absent, minimal or unexpected in trials. These findings suggest a role for population context in determining health responses and filling extensive gaps in knowledge. Multiple micronutrient supplements reduce the risks of being born with low birth weight, small for gestational age or stillborn in undernourished settings, and justify micronutrient interventions with antenatal care. Measurable health effects of gestational micronutrient exposure might persist into childhood but few data exists on potential long-term benefits. In this Review, we discuss micronutrient intake recommendations, risks and consequences of deficiencies, and the effects of interventions with a particular emphasis on offspring.

Hypovitaminosis D in pregnancy in the Mediterranean region: a systematic review

Despite high levels of sunshine, maternal hypovitaminosis D during pregnancy is prevalent in the Mediterranean region. The aim of this study is to systematically review trials that investigated vitamin D concentrations during pregnancy in this region, in order to determine predictors of hypovitaminosis D and explain this phenomenon. After applying inclusion/exclusion criteria, 15 studies were entered into the systematic review involving 2649 pregnant women and 820 neonates. The main outcome was maternal vitamin D status, assessed by serum 25-hydroxy-vitamin D (25(OH)D) concentrations. Possible predictors of the outcome included maternal age, body mass index (BMI), race, socioeconomic status, skin type, gestational age, sun exposure, calcium and vitamin D intake and supplementation, smoking status, parity and season of delivery. Studies differed widely in vitamin D deficiency criteria, method of measurement and outcomes. The prevalence of vitamin D insufficiency ranges from 9.3 to 41.4%, whereas that of vitamin D deficiency from 22.7 to 90.3%. A positive association with 25(OH)D concentrations exists for light skin color, white race, uncovered dressing pattern, maternal vitamin D supplementation and season of gestation (spring/summer). An inverse association exists for BMI and gestational age, whereas data for smoking and socioeconomic status are controversial. We concluded that vitamin D deficiency in pregnancy seems to be quite common, even in the Mediterranean region. Racial, social and cultural habits, as well as the absence of preventive supplementation/dietary strategies, seem to negate the benefits of sun exposure.

Vitamin D during pregnancy: why observational studies suggest deficiency and interventional studies show no improvement in clinical outcomes? A narrative review

A considerable number of studies have examined vitamin D status during pregnancy. Although data from observational studies denote vitamin D hypovitaminosis (deficiency or insufficiency) during pregnancy is associated with a plethora of adverse maternal and neonatal outcomes, data from interventional (supplementation) trials fail to reveal a significant impact on maternal and offspring health. The aim of this narrative review was to critically appraise the methodology of the most representative published randomized controlled trials in an attempt to explain the difference between observational and supplementation results. We found that this difference could be attributed to a variety of factors, namely: (i) study design (lack of a specific outcome in conjunction with timing of supplementation, enrolment of participants with heterogeneous vitamin D status); (ii) pitfalls in the interpretation of vitamin D equilibrium (lack of determination of plasma half-life); (iii) supplementation regimen (administration of a wide range of regimens, in terms of dose, bolus and form); (iv) geographical characteristics (vitamin D needs could vary significantly within a country, particularly in areas with a wide range of latitude gradient); (v) adaptations of vitamin D metabolism during pregnancy (vitamin D and calcium equilibrium are changed during pregnancy compared with the non-pregnant state) and (vi) supplementation of populations with low baseline 25(OH)D values would likely manifest beneficial effects. All these parameters should be taken into consideration in the design of future vitamin D supplementation trials.

Bone metabolic changes during pregnancy: a period of vulnerability to osteoporosis and fracture

Changes in bone density and bone markers suggest that pregnancy is associated with deterioration of bone mass in the mother. The metabolism of calcium resets to allow for the needs imposed by the building of the fetal skeleton. The fetus contributes to the process through the output of regulators from the placenta. Understanding of the whole process is limited, but some changes are unambiguous. There is an increase in the circulating levels of vitamin D, but its functional impact is unclear. Fetal parathyroid hormone (PTH) and PTH-related peptide (PTHrp) play an indirect role through support of a calcium gradient that creates hypercalcemia in the fetus. Placental GH, which increases up to the end of pregnancy, may exert some anabolic effects, either directly or through the regulation of the IGF1 production. Other key regulators of bone metabolism, such as estrogens or prolactin, are elevated during pregnancy, but their role is uncertain. An increase in the ratio of receptor activator of nuclear factor kappa B ligand (RANKL) to osteoprotegerin (OPG) acts as an additional pro-resorbing factor in bone. The increase in bone resorption may lead to osteoporosis and fragility fracture, which have been diagnosed, although rarely. However, the condition is transitory as long-term studies do not link the number of pregnancies with osteoporosis. Prevention is limited by the lack of identifiable risk factors. When fractures are diagnosed, rest, analgesics, or, when indicated, orthopedic intervention have demonstrated efficacy. Systemic treatment with anti-osteoporotic drugs is effective, but the potential harm to the fetus imposes caution in their use.

Regulation of calcitriol biosynthesis and activity: focus on gestational vitamin D deficiency and adverse pregnancy outcomes

Vitamin D has garnered a great deal of attention in recent years due to a global prevalence of vitamin D deficiency associated with an increased risk of a variety of human diseases. Specifically, hypovitaminosis D in pregnant women is highly common and has important implications for the mother and lifelong health of the child, since it has been linked to maternal and child infections, small-for-gestational age, preterm delivery, preeclampsia, gestational diabetes, as well as imprinting on the infant for life chronic diseases. Therefore, factors that regulate vitamin D metabolism are of main importance, especially during pregnancy. The hormonal form and most active metabolite of vitamin D is calcitriol. This hormone mediates its biological effects through a specific nuclear receptor, which is found in many tissues including the placenta. Calcitriol synthesis and degradation depend on the expression and activity of CYP27B1 and CYP24A1 cytochromes, respectively, for which regulation is tissue specific. Among the factors that modify these cytochromes expression and/or activity are calcitriol itself, parathyroid hormone, fibroblast growth factor 23, cytokines, calcium and phosphate. This review provides a current overview on the regulation of vitamin D metabolism, focusing on vitamin D deficiency during gestation and its impact on pregnancy outcomes.