High prevalence of vitamin D deficiency in newborn infants of high-risk mothers

Gut microbiota: Linking nutrition and perinatal depression

Perinatal depression is a mood disorder that is reported in women during pregnancy (prenatal) and after childbirth (postnatal). The onset of perinatal depression is associated with changes in reproductive hormones, stress hormones and neurosteroids. These chemical compounds can be modulated by the gut microbiota, which may affect maternal mental health during the perinatal period via the gut-brain-axis. Recent studies suggest that nutritional and dietary interventions (vitamin D, ω-3 fatty acids, iron, and fiber) effectively prevent or mitigate maternal depression and anxiety, but their efficacy is confounded by various factors, including the gut microbiota. Probiotics are efficacious in maintaining microbiota homeostasis, and thus, have the potential to modulate the development of perinatal mood disorders, despite no evidence in human. Therefore, clinical trials are warranted to investigate the role of probiotic supplementation in perinatal depression and behavioral changes. This article reviews the interplay between nutrition, gut microbiota and mood and cognition, and the evidence suggesting that probiotics affect the onset and development of perinatal depression.

Influence of maternal socioeconomic deprivation and living environment on newborn bloodspot 25-hydroxyvitamin D levels

Objectives

Vitamin D deficiency in neonates can have life-threatening consequences, hence the knowledge of risk factors is essential. This study aimed to explore the effect of maternal socioeconomic status (SES) on newborn 25-hydroxyvitamin D (25OHD) concentrations.

Design

Over two 1-week periods (winter and summer of 2019), 3000 newborn heel prick dried blood spots (DBS) and additional data of newborns, from a regional newborn screening laboratory (52° N) in the West Midlands, UK, were gathered. Post code was replaced with lower layer super output area (LSOA). Index of Multiple Deprivation (IMD) quintiles for the corresponding LSOA was used to assess SES [quintile one (Q1): most deprived 20%, quintile five (Q5): least deprived 20%]. Each of the seven domains of deprivation were examined (income, employment, education, health, barriers to housing and services, crime and living environment). 25OHD was measured on 6mm sub-punch from DBS using quantitative liquid chromatography tandem mass spectrometry and equivalent plasma values were derived.

Results

In total 2999 (1500 summer-born, 1499 winter-born) newborn DBS (1580 males) were analysed. Summer-born newborns had significantly higher 25OHD (IQR) concentrations [49.2 (34.3; 64.8) nmol/l] than winter-born newborns [29.1 (19.8; 40.6) nmol/l, p<0.001].25OHD levels varied significantly between the different IMD quintiles in the whole (p<0.001) and summer-born cohort (p<0.001), but not in the winter-born cohort (p=0.26), whereby Q1 had the lowest 25OHD concentrations. Among the domains of deprivation, living environment had a significant influence on 25OHD levels (β=0.07, p=0.002). In this subdomain, 25OHD levels varied significantly between quintiles in the whole (p<0.001) and summer-born cohort (mean 25OHD Q1 46.45 nmol/l, Q5 54.54 nmol/l; p<0.001) but not in the winter-born cohort (mean 25OHD Q1 31.57 nmol/l, Q5 31.72 nmol/l; p=0.16). In a regression model, living environment was still significant (p=0.018), albeit less than season of birth and ethnicity.

Conclusion

Among the seven domains of deprivation, maternal living environment had the greatest effect on newborn 25OHD levels. Whilst improved living environment positively influenced vitamin D status in the summer-born babies, winter-born had low 25OHD levels irrespective of the environment. Strategies such as enhanced supplementation and food fortification with vitamin D should be considered to overcome the non-modifiable main risk factors for vitamin D deficiency.

Vitamin D Deficiency Prevalence in Late Neonatal Hypocalcemia: A Multicenter Study

OBJECTIVE

Late neonatal hypocalcemia (LNH) is a common metabolic problem associated with hypoparathyroidism, high phosphate intake and vitamin D deficiency, often presenting with seizures. In this cross-sectional study, we aimed to evaluate the role of vitamin D deficiency in LNH in Turkey and to describe the characteristics of affected newborns.

METHODS

Conducted with a cross-sectional design and with the participation of 61 neonatal centers from December 2015 to December 2016, the study included term neonates with LNH (n=96) and their mothers (n=93). Data were registered on the FAVOR Web Registry System. Serum samples of newborns and mothers were analyzed for calcium, phosphate, magnesium, albumin, alkaline phosphatase, intact parathyroid hormone (iPTH) and 25 hydroxyvitamin D [25(OH)D] levels.

RESULTS

The median (range) onset time of hypocalcemia was 5.0 (4.0-8.0) days of age, with a male preponderance (60.4%). The median (range) serum 25(OH)D levels of the neonates and their mothers were 6.3 (4.1-9.05) and 5.2 (4.7-8.8) ng/mL, respectively. The prevalence of vitamin D deficiency (<12 ng/mL) was high in both the neonates (86.5%) and mothers (93%). Serum 25(OH)D levels of the infants and mothers showed a strong correlation (p<0.001). While the majority (93.7%) of the neonates had normal/high phosphorus levels, iPTH levels were low or inappropriately normal in 54.2% of the patients.

CONCLUSION

Vitamin D deficiency prevalence was found to be high in LNH. Efforts to provide vitamin D supplementation during pregnancy should be encouraged. Evaluation of vitamin D status should be included in the workup of LNH.

Pooled estimate of vitamin D deficiency among pregnant women in India: a systematic review and meta-analysis

BACKGROUND

Vitamin D deficiency among pregnant women is a public health concern globally. In India, individual studies report high prevalence. However, lack of national data masks the true burden. This work determined the pooled prevalence of vitamin D deficiency among pregnant women in India through a systematic review of literature and meta-analysis.

METHODS

Three different search engines yielded 15 eligible articles. Study quality was assessed by 10 different criteria and summary of study quality was categorized as per Cochrane standards. Meta-analysis was performed to estimate pooled prevalence of vitamin D deficiency among healthy pregnant women and heterogeneity among selected studies. A sample of n = 4088 was used to study the pooled prevalence among pregnant women.

RESULTS

The random effects combined estimate was 32.35% (95% CI, (12.58-117.48). High heterogeneity (tau² = 0.39, I² = 100%) and high risk of bias was observed among the selected studies. The test for overall effect was observed to be z = 2.54(P = 0.01).

CONCLUSION

Pooled estimate > 30% emphasizes the need for screening through antenatal care services and initiate preventive measures to address the deficiency.

Cord Blood Vitamin D Levels and Early Childhood Blood Pressure: The Healthy Start Study

Background Vitamin D deficiency is associated with cardiovascular events among adults, but it is unclear whether early-life vitamin D deficiency influences cardiovascular risk factors in children. Methods and Results We measured total and bioavailable 25-dihydroxyvitamin D (25OHD) in cord blood and in blood from 4- to 6-year-old children, and we assessed cardiovascular risk factors (blood pressure, arterial stiffness, body size, and adiposity) at 4 to 6 years. We tested for racial/ethnic differences in total and bioavailable 25OHD (n=715) and modeled the adjusted association between cord blood 25OHD and childhood cardiovascular risk factors (n=171). We observed racial/ethnic differences in total and bioavailable 25OHD levels in both cord and child blood samples (all P<0.05). Each 25-nmol/L increase in cord blood total 25OHD was associated with a 2.5-mm Hg (SE 0.8) decrease in systolic blood pressure ( P=0.002) and a 1.7-mm Hg (SE 0.6) decrease in diastolic blood pressure ( P=0.01), independent of childhood 25OHD levels, race/ethnicity, and other covariates. There was no association between cord blood total 25OHD and any other cardiovascular risk factors. Cord blood levels of bioavailable and free 25OHD were not associated with any cardiovascular risk factor in childhood. Conclusions In this diverse prebirth cohort, we observed lower systolic and diastolic blood pressure among children with higher total 25OHD levels at birth. Our findings suggest that intrauterine exposure to vitamin D may contribute to early-life programming of offspring blood pressure. Intervention studies are needed to determine whether increasing fetal vitamin D exposure can reduce the risk of elevated blood pressure in childhood.

Serum 25 hydroxyvitamin D levels and affecting factors among preconception fertile women

Background

Recent study found that vitamin D before conception was considered as a potential additional determinant for achieving pregnancy and live births. The study aimed to evaluate the serum 25 hydroxyvitamin D (25(OH)D) levels and its affecting factors among preconception fertile women.

Methods

This cross-sectional study enrolled 410 women aged 22–44 years who attended a preconception genetic counseling clinic from January 2018 to May 2019. Sociodemographic characteristics and reproductive history of women were collected, and height and weight were measured. Serum 25(OH)D concentration was assayed with chemiluminescence immunoassay. Descriptive statistics were used to examine serum 25(OH)D concentration, and socio-demographic characteristics and reproductive history among preconception women. Determinants of vitamin D deficiency and its affecting factors were assessed using χ2 test and logistic regression.

Results

Findings showed 84.4% of women had serum 25(OH)D concentration below 20 ng/mL. Women working indoors as well as without a history of childbirth had significantly lower 25(OH)D levels compared with those non-working individuals and having delivered a previous child (both P < 0.05). The 25(OH)D levels were the lowest in winter among that in spring, summer, and autumn (all P < 0.001). Women in winter have significantly elevated OR of 5.00 (95%CI 1.75–14.25) to develop vitamin D deficiency. Seasonal variation in serum 25(OH)D levels was not present in non-working individuals and women aged 31–44 years.

Conclusions

Vitamin D deficiency is common among preconception women especially nulliparous women and working women, which propose to screen serum 25(OH)D on preconception evaluation and emphasize need vitamin D supplements and get sunshine exposure.

Screening of vitamin D and calcium concentrations in neonates of mothers at high risk of vitamin D deficiency

Objective

The aim of this study was to determine, retrospectively, the serum 25OHD and calcium concentrations of screened neonates of mothers at high risk of 25OHD deficiency and examine whether their measurement contributes to the management of these neonates.

Methods

Serum 25OHD and calcium concentrations from 600 samples of umbilical cord blood or venous blood collected from neonates over a 12-month period were analysed.

Results

There was a high prevalence of vitamin D insufficiency (27.6%, 30–50 nmol/L) and deficiency (21.3%, < 30 nmol/L) in neonates from high-risk maternal groups. There was a statistically positive but weak correlation (ρ = 0.22, P < 0.0001) between 25OHD and serum calcium. Only 7 neonates out of 569 (1.2%) had calcium concentrations in the hypocalcaemic range; however, a significant number (47.6%) were reported to be in the hypercalcaemic range. Nearly all of these were venous samples collected in first 24 h after birth.

Conclusion

Vitamin D deficiency is prevalent in neonates of high-risk mothers but the risk of hypocalcaemia due to vitamin D deficiency at birth is low. Screening neonates entails blood testing which can cause distress to neonates and their parents, substantial imposition on staff and financial burden on the health care system. Vitamin D supplementation of these neonates from birth without routine screening appears more reasonable. Also, the data from this study suggest that the paediatric reference range for corrected calcium concentrations in neonates should be re-evaluated.

Maternal and neonatal 25-hydroxyvitamin D concentrations and school-age lung function, asthma and allergy. The Generation R Study

BACKGROUND

Vitamin D deficiency in early life might affect the developing lung and immune system, and subsequently influence the risk of asthma and allergy in later life.

OBJECTIVE

We examined the associations of 25-hydroxyvitamin D concentrations in mid-gestation and at birth with lung function, asthma, inhalant allergic sensitization and inhalant allergy at school-age.

METHODS

This study among 4951 children and their mothers was embedded in a population-based prospective cohort in Rotterdam, the Netherlands. Maternal venous blood samples in mid-gestation and umbilical cord blood samples at birth were used to determine 25-hydroxyvitamin D concentrations. At age 10 years, lung function was measured by spirometry, current asthma and physician-diagnosed inhalant allergy by questionnaire, and inhalant allergic sensitization by skin prick tests. We used multivariable regression models to examine associations.

RESULTS

Higher 25-hydroxyvitamin D concentrations in mid-gestation were associated with a higher forced vital capacity (FVC), but a lower forced expiratory volume in 1 second/FVC (FEV₁ /FVC) and a lower forced expiratory flow after exhaling 75% of FVC (FEF₇₅ ) (Z-score differences [95% CI] 0.02 [0.00, 0.03], -0.02 [-0.03, -0.01] and -0.01 [-0.03, -0.00], respectively, per 10 nmol/L 25-hydroxyvitamin D), but not with asthma. Furthermore, higher 25-hydroxyvitamin D concentrations in mid-gestation were associated with an increased risk of inhalant allergy (Odds Ratio [95% CI] 1.07 [1.02, 1.12]), but not with inhalant allergic sensitization. After additional adjustment for child's 25-hydroxyvitamin D concentrations at the age of 6 years, only the associations of 25-hydroxyvitamin D concentrations in mid-gestation with FEV₁ /FVC and FEF₇₅ remained. We did not find consistent associations of 25-hydroxyvitamin D concentrations at birth with respiratory or allergy outcomes.

CONCLUSION AND CLINICAL RELEVANCE

Our results suggest that maternal 25-hydroxyvitamin D concentrations in mid-gestation may influence lung development. The clinical implications of the observed associations remain unclear.

Vitamin D Deficiency and Antenatal and Postpartum Depression: A Systematic Review

Vitamin D has been implicated in antenatal depression (AD) and postpartum depression (PPD) in many studies; however, results have been inconsistent due to the complexity of this association. We searched the MEDLINE, Embase, PsycINFO, and Maternity and Infant Care databases for literature addressing associations between vitamin D and AD and PPD. Two independent authors reviewed titles and abstracts of the search results and selected studies for full review. Data were extracted, and a quality rating was done using the Newcastle-Ottawa Scale (NOS) on the selected studies. A total of 239 studies were identified; 14 were included in the review. The quality assessment of the included studies ranged from moderate to high. Of the studies on PPD, five of nine (55%) showed a significant association between vitamin D and PPD. Five of seven (71%) studies on AD showed a significant association with vitamin D status. As the included studies used different effect estimates and statistical analyses to report the association, it was not possible to transform the existing data into one single effect measure to employ meta-analytic techniques. While results of this systematic review vary, they indicate a significant association between vitamin D status and AD and PD.

Non-skeletal health effects of vitamin D supplementation: A systematic review on findings from meta-analyses summarizing trial data

BACKGROUND

A large number of observational studies have reported harmful effects of low 25-hydroxyvitamin D (25OHD) levels on non-skeletal outcomes. We performed a systematic quantitative review on characteristics of randomized clinical trials (RCTs) included in meta-analyses (MAs) on non-skeletal effects of vitamin D supplementation.

METHODS AND FINDINGS

We identified systematic reviews (SR) reporting summary data in terms of MAs of RCTs on selected non-skeletal outcomes. For each outcome, we summarized the results from available SRs and scrutinized included RCTs for a number of predefined characteristics. We identified 54 SRs including data from 210 RCTs. Most MAs as well as the individual RCTs reported null-findings on risk of cardiovascular diseases, type 2 diabetes, weight-loss, and malignant diseases. Beneficial effects of vitamin D supplementation was reported in 1 of 4 MAs on depression, 2 of 9 MAs on blood pressure, 3 of 7 MAs on respiratory tract infections, and 8 of 12 MAs on mortality. Most RCTs have primarily been performed to determine skeletal outcomes, whereas non-skeletal effects have been assessed as secondary outcomes. Only one-third of the RCTs had low level of 25OHD as a criterion for inclusion and a mean baseline 25OHD level below 50 nmol/L was only present in less than half of the analyses.

CONCLUSIONS

Published RCTs have mostly been performed in populations without low 25OHD levels. The fact that most MAs on results from RCTs did not show a beneficial effect does not disprove the hypothesis suggested by observational findings on adverse health outcomes of low 25OHD levels.

Vitamin D status of White pregnant women and infants at birth and 4 months in North West England: A cohort study

The prevalence of vitamin D deficiency in pregnant white-skinned women (WSW) and their infants has not been investigated at northern latitudes in a developed county. A 2-year observational cohort study was undertaken in the North West of England to determine 25-hydroxyvitamin D (25OHD) levels in WSW and their infants during pregnancy and 4 months postdelivery and to explore factors associated with these levels. Nutritional and lifestyle questionnaires were completed and 25OHD levels measured at 28 weeks and 4 months postdelivery. Twenty-seven percent and 7% of WSW had insufficient and deficient levels of 25OHD during pregnancy and 48% and 11% four months postdelivery. WSW with Fitzpatrick skin-type I (FST I) have significantly lower 25OHD than other skin types after controlling for time spent outside and vitamin D intake. Twenty-four percent and 13% of infants had insufficient and deficient 25OHD levels at 4 months. Unsupplemented breast-fed infants have the highest level of insufficiency (67%) compared with formula-fed infants (2%). Factors associated with infant serum 25OHD levels at 4 months included breast feeding, supplementation, and time outside. WSW have a high prevalence of insufficiency and deficiency during pregnancy which doubles 4 months after birth. Breast-fed infants of WSW are rarely considered at risk of vitamin D insufficiency but have high rates compared with formula-fed infants. This is the first study to show the finding that FST I WSW have significantly lower levels of 25OHD than those with FST II-IV (difference adjusted for diet and time outside 14 (95%CI 7-21) nmol/L).

Global summary of maternal and newborn vitamin D status - a systematic review

Pregnant women and newborns are at increased risk of vitamin D deficiency. Our objective was to create a global summary of maternal and newborn vitamin D status. We completed a systematic review (1959-2014) and meta-analysis of studies reporting serum 25-hydroxyvitamin D [25(OH)D] concentration in maternal and newborn populations. The 95 identified studies were unevenly distributed by World Health Organization (WHO) region: Americas (24), European (33), Eastern Mediterranean (13), South-East Asian (7), Western Pacific (16) and African (2). Average maternal 25(OH)D concentrations (nmol L(-1) ) by region were 47-65 (Americas), 15-72 (European), 13-60 (Eastern Mediterranean), 20-52 (South-East Asian), 42-72 (Western Pacific) and 92 (African). Average newborn 25(OH)D concentrations (nmol L(-1) ) were 35-77 (Americas), 20-50 (European), 5-50 (Eastern Mediterranean), 20-22 (South-East Asian), 32-67 (Western Pacific) and 27-35 (African). The prevalences of 25(OH)D <50 and <25 nmol L(-1) by WHO region in pregnant women were: Americas (64%, 9%), European (57%, 23%), Eastern Mediterranean (46%, 79%), South-East Asian (87%, not available) and Western Pacific (83%, 13%). Among newborns these values were: Americas (30%, 14%), European (73%, 39%), Eastern Mediterranean (60%, not available), South-East Asian (96%, 45%) and Western Pacific (54%, 14%). By global region, average 25(OH)D concentration varies threefold in pregnant women and newborns, and prevalence of 25(OH)D <25 nmol L(-1) varies eightfold in pregnant women and threefold in newborns. Maternal and newborn 25(OH)D concentrations are highly correlated. Addressing vitamin D deficiency in pregnant women and newborns should be a global priority. To protect children from the adverse effects of vitamin D deficiency requires appropriate interventions during both pregnancy and childhood.

Autism spectrum disorder and low vitamin D at birth: a sibling control study

BACKGROUND

Insufficient vitamin D activity has attracted increasing interest as a possible underlying risk factor in disorders of the central nervous system, including autism.

METHODS

In this study, 25-hydroxyvitamin D (25(OH)D) was analysed in 58 Sweden-born sibling pairs, in which one child had autism spectrum disorder (ASD) and the other did not. The study group consisted of two representative samples; 47 Gothenburg sibling pairs with mixed ethnicities and 11 Stockholm sibling pairs with Somali background. 25(OH)D levels were analysed in the stored dried blood spots taken in the neonatal period for metabolic screening.

RESULTS

The collapsed group of children with ASD had significantly lower vitamin D levels (M = 24.0 nM, SD = 19.6) as compared with their siblings (M = 31.9 nM, SD = 27.7), according to a paired samples t-test (P = 0.013). The difference was - most likely - not only accounted for by a difference in season of birth between ASD and non-ASD siblings since the mean 25(OH)D levels differed with similar effect size between the sibling pairs born during winter and summer, respectively. All children with African/Middle East background, both the children with ASD and their non-ASD siblings, had vitamin D deficiency.

CONCLUSIONS

The findings suggest that low prenatal vitamin D may act as a risk factor for ASD, however, there is a need for replication with larger samples. Future research should study whether or not adequate supplementation of vitamin D to pregnant women might lower the risk for ASD in the offspring.

Vitamin D deficiency among native Dutch and first- and second-generation non-Western immigrants

The aim of this study was to determine the prevalence of 25-hydroxyvitamin D (25(OH)D) deficiency in a hospital-based population of both native Dutch and non-Western immigrants and to investigate the influence of immigrant status on the prevalence of vitamin D deficiency. A cross-sectional survey was conducted among 132 patients (1-18 years of age) visiting the paediatric outpatient department. Serum levels of 25(OH)D were measured using high-performance liquid chromatography. Cut-off levels of 30 and 50 nmol/l for serum 25(OH)D were evaluated. One third of the patients had serum 25(OH)D levels below 30 nmol/l, and half of the study population had serum levels below 50 nmol/l. Non-Western immigrants had an increased risk for vitamin D deficiency compared to their native Dutch peers [25(OH)D of <30 nmol/l, p = 0.03, odds ratio (OR) 3.87 (95 % confidence interval (CI) 1.13-13.29); 25(OH)D of <50 nmol/l, p = 0.02, OR 3.57 (95 % CI 1.26-10.14)] with the highest risk for first-generation non-Western immigrants.

CONCLUSION

Vitamin D deficiency in the paediatric population is still a matter of concern in the Netherlands, in particular among first-generation non-Western immigrants. We therefore strongly recommend vitamin D supplementation for all non-Western immigrants, regardless of age, skin type or season. Health-care staff who work with non-Western immigrants should be aware of the prevalence and implications of vitamin D deficiency.

Comparison of two regimens of vitamin D supplementation for vitamin D-deficient neonates

INTRODUCTION

Vitamin D deficiency is common in pregnant women, and supplementation of vitamin D is necessary for the infants of these women. This study explored the efficacy of an alternative way of vitamin D supplementation in an area with a high prevalence of vitamin D deficiency in mothers.

METHODS

This was a non-randomised clinical trial conducted in 2010 in Yazd, Iran. Full-term healthy infants born to vitamin D-deficient mothers (n = 82) were divided into the high-dose regimen (HDR; single oral bolus 30,000 IU vitamin D3, n = 34) and the standard-dose regimen (SDR; 400 IU/day vitamin D3 within two weeks of life, n = 48) groups. 25-hydroxyvitamin D (25OHD) was measured using chemiluminescent immunoassays, and 25OHD level > 20 ng/mL was deemed sufficient.

RESULTS

Over 90% of infants in the HDR group attained vitamin D sufficiency within one month, while comparable sufficiency was reached in the SDR group only after four months. At two months, the proportion of infants attaining 25OHD > 30 ng/mL was 93.3% and 27.9% in the HDR and SDR groups, respectively (p = 0.003). None of our infants achieved 25OHD levels > 100 ng/mL.

CONCLUSION

For infants born to vitamin D-deficient mothers, oral supplementation of 30,000 IU vitamin D3 during the first month of life, followed by a routine recommended dose of 400 IU/day, should be considered. The four-month lag for attaining vitamin D sufficiency in 90% of infants in the SDR group may have clinical implications and should be further investigated.

Vitamin D deficiency in cord plasma from multiethnic subjects living in the tropics

BACKGROUND

Vitamin D deficiency is commonly reported in high-latitude areas and in dark-pigmented individuals. However, nothing is known about vitamin D in cord blood from multiethnic subjects living in the tropics.

OBJECTIVE

Our study objective was to determine the prevalence of vitamin D deficiency in summer and winter in cord blood from multiethnic individuals in Hawai'i where sufficient sun irradiance occurs year-round for cutaneous vitamin D production.

METHODS

25-Hydroxyvitamin D (25(OH)D) levels were quantified by enzyme immunoassay in 100 cord plasma samples from apparently healthy full-term newborns and their mothers. Stratification was performed by birth season and ethnicity.

RESULTS

Mean 25(OH)D levels were 24.5 ng/mL (9.1-68.3 ng/mL). Overall, 28% of samples were vitamin D deficient (<20 ng/mL) and 50% were insufficient (20-30 ng/mL). 25(OH)D levels (ng/mL) were highest in Caucasians (30.5, n = 19), followed by Asians (25.1, n = 43), Hispanics (21.5, n = 3), Pacific Islanders (20.0, n = 25), and African Americans (19.6, n = 2). Differences among groups were significant (p = 0.008). Cord plasmas from summer versus winter were higher overall (p = 0.001) and among Asians (p = 0.0003). Seasonal changes were correlated with sun irradiance overall (r = 0.43, p = 0.0001), among Caucasians (r = 0.45, p = 0.05), and among Asians (r = 0.45, p = 0.0001).

CONCLUSION

Our results suggest that prenatal supplement recommendations of 400 IU vitamin D/day do not protect against vitamin D deficiency, even in subjects living in the tropics where ample sun irradiance exists for cutaneous vitamin D synthesis. The high prevalence of vitamin D deficiency we observed emphasizes the necessity for regular 25(OH)D monitoring, particularly during pregnancy and lactation, in dark-pigmented individuals, and during winter months.

Vitamin D hormone regulates serotonin synthesis. Part 1: relevance for autism

Serotonin and vitamin D have been proposed to play a role in autism; however, no causal mechanism has been established. Here, we present evidence that vitamin D hormone (calcitriol) activates the transcription of the serotonin-synthesizing gene tryptophan hydroxylase 2 (TPH2) in the brain at a vitamin D response element (VDRE) and represses the transcription of TPH1 in tissues outside the blood-brain barrier at a distinct VDRE. The proposed mechanism explains 4 major characteristics associated with autism: the low concentrations of serotonin in the brain and its elevated concentrations in tissues outside the blood-brain barrier; the low concentrations of the vitamin D hormone precursor 25-hydroxyvitamin D [25(OH)D3]; the high male prevalence of autism; and the presence of maternal antibodies against fetal brain tissue. Two peptide hormones, oxytocin and vasopressin, are also associated with autism and genes encoding the oxytocin-neurophysin I preproprotein, the oxytocin receptor, and the arginine vasopressin receptor contain VDREs for activation. Supplementation with vitamin D and tryptophan is a practical and affordable solution to help prevent autism and possibly ameliorate some symptoms of the disorder.

Obesity and Vitamin D Deficiency - Current Concepts on their Impact on Pregnancy

Both obesity and vitamin D deficiency are linked to morbidity and ultimately mortality. Vitamin D sufficiency is believed to confer many health benefits; however, with the exception of the classic functions related to bone health these are not yet well understood, especially in relationship to pregnancy and infant health outcomes.1 Conversely, insufficiency is associated with adverse health outcomes, which are consequently related to public health concerns that arise from these and these need addressing.2,3 While the links between health and vitamin D are being considered and researched, there are an increasing number of reports that demonstrate vitamin D deficiency is prevalent particularly among people who are darker skinned, those who live at latitudes above 52°, and are therefore exposed to reduced sunlight especially in the autumn and winter months, those who through lifestyle choices cover their bodies, preventing sunlight exposure, and in obese people.3-6 Obesity is also of growing concern. Health journalists and academics sometimes dramatically refer to 'obesity epidemics,' which is not surprising as over one-third of Americans are obese.7-9 This problem, if not addressed, will lead to adverse health outcomes for individuals as well as being a long-term burden both to families and society.10-11 It is interesting to note that both vitamin D deficiency and obesity have shared risks for mortality and morbidity including cardiovascular disease, diabetes, respiratory problems, cancer and musculoskeletal disease. This paper considers current concepts and the links between obesity and vitamin D deficiency in pregnancy seeking to determine whether being vitamin D deficient and obese is simply double trouble, where both are present, or whether there are there other factors that need further exploration, reviewing the associated implications for practice.12-15.

Impact of maternal vitamin D status during pregnancy on the prevalence of neonatal vitamin D deficiency

Maternal vitamin D deficiency is not uncommon. The lack of vitamin D during pregnancy may result in poor fetal growth and altered neonatal development that may persist into later life. Recognition of risk factors and early detection of vitamin D deficiency during pregnancy is important in order to prevent neonatal vitamin D deficiency and related complications. The aim of the current study is to assess the effect of maternal vitamin D status on the neonatal vitamin D stores. A total of 92 pregnant women at the end of the 3(rd) trimester and their newborns were recruited from Al Khafji Joint Operation Hospital, Saudi Arabia, during the year 2011. Maternal and cord blood samples were taken for determination of serum levels of circulating 25-hydroxyvitamin D3 [25(OH)D3] concentration, serum calcium (Ca(++)), phosphorus (PO4) and alkaline phosphatase (ALP). Compared with pregnant women with adequate vitamin D levels, women deficient in vitamin D had infants with vitamin D deficiency (X±SD 33.44±18.33 nmol/L vs 55.39±17.37 nmol/L, P=0.01). Maternal and neonatal serum 25(OH)D3 levels showed a positive correlation with serum Ca(++) and negative correlation with serum PO4 and ALP. Neonatal 25(OH)D was related to maternal 3(rd) trimester levels (r=0.89, P=0.01). The newborn serum 25(OH)D3 concentrations rely on maternal vitamin D status. Poor maternal vitamin D status may adversely affect neonatal vitamin D status and, consequently, calcium homeostasis.

Vitamin D deficiency in pregnancy - still a public health issue

The objectives of this study were to quantify the prevalence of vitamin D insufficiency and deficiency in pregnancy, explore associated risk factors and discuss the public health implications. The study used retrospective analysis of randomly selected data. This is the first report on serum vitamin D levels in an unselected multi-ethnic population of pregnant women collected between April 2008 and March 2009. Women with sufficient stored serum were randomly selected from among all women who delivered between April 2008 and March 2009. Serum vitamin D levels were determined using liquid chromatography coupled to tandem mass spectrometry. Vitamin D levels were analysed with respect to ethnicity (marking skin tone), calendar quartile, body mass index (BMI), trimester and parity. Deficiency was defined as <25 nmol L(-1) , insufficiency 25-75 nmol L(-1) and adequacy >75 nmol L(-1) . Three hundred and forty-six women were included and represented the total population regarding skin tone, quartile, BMI, gestation and parity. Overall, 18% [95% confidence interval (CI): 15-23%] of sample women had adequate vitamin D levels; 36% were deficient, 45% insufficient. Among women with dark skin, only 8% (95% CI: 5-12%) had adequate levels compared with 43% (95% CI: 33-53%) of those with light skin. Obese women were found have significantly lower vitamin D levels than non-obese women. Vitamin D deficiency and insufficiency are prevalent year-round among pregnant women in North West London, especially those with darker skin. Existing supplementation guidelines should be supported; however, other measures are required to improve status among all women.

High prevalence of vitamin D deficiency in pregnant women: a national cross-sectional survey

An increasing number of studies suggest that vitamin D deficiency during pregnancy is associated with multiple adverse health outcomes in mothers, neonates and children. There are no representative country data available on vitamin D status of pregnant women in Europe. The aim of this study was to estimate the prevalence of vitamin D deficiency among Belgian pregnant women and to assess the determinants of vitamin D status in the first and third trimester of pregnancy. The women were selected via a multi-stage proportionate-to-size sampling design. Blood samples were collected and a questionnaire was completed face-to-face. 55 obstetric clinics were randomly selected and 1311 pregnant women participated in the study. The median serum 25-hydroxyvitamin D [25-(OH)D] concentration was significantly lower in the first trimester (20.4 ng/ml) than in third trimester (22.7 ng/ml). Of all women, 74.1% (95%CI = 71.8–76.5%) were vitamin D insufficient (25-(OH)D <30 ng/ml), 44.6% (95%CI = 41.9–47.3%) were vitamin D deficient (25-(OH)D <20 ng/ml), while 12.1% (95%CI = 10.3–13.8%) were severely vitamin D deficient (25-(OH)D <10 ng/ml). Of all women included, 62.0% reported taking vitamin D-containing multivitamins, of which only 24.2% started taking those before pregnancy. The risk of vitamin D deficiency (25-(OH)D <20 ng/ml) was significantly higher for less educated women and women who reported not going on holidays to sunny climates. The risk of severe vitamin D deficiency (25-(OH)D <10 ng/ml) decreased for women who reported alcohol consumption during pregnancy, decreased with more frequent use of sunscreen lotion and increased for smokers and women who reported preference for shadow. In conclusion, vitamin D deficiency is highly prevalent among pregnant women in Belgium and this raises concerns about the health consequences for the mother and the offspring. A targeted screening strategy to detect and treat women at high risk of severe vitamin D deficiency is needed in Belgium and in Europe.

Factors Associated with Vitamin D Deficiency and Inadequacy among Women of Childbearing Age in the United States

Objective. To examine the prevalence and correlates of vitamin D deficiency and inadequacy among US women of childbearing age. Methods. Data from 1,814 female participants (20-44 y) in the 2003-2006 NHANES were analyzed to estimate the age-adjusted prevalence and prevalence ratios with 95% confidence intervals (CIs) for vitamin D deficiency (defined as serum 25-hydroxyvitamin D [25(OH)D] <12.0 ng/mL) and inadequacy (defined as 25(OH)D: 12.0-<20.0 ng/mL). Results. The age-adjusted prevalence was 11.1% (95% CI: 8.8-14.0%) for vitamin D deficiency and 25.7% (95% CI: 22.3-29.5%) for vitamin D inadequacy. Race/ethnicity other than non-Hispanic white and obesity were associated with increased risks, whereas dietary supplement use, milk consumption of ≥1 time/day, and potential sunlight exposure during May-October were associated with decreased risks for both vitamin D deficiency and inadequacy (P < 0.05). Current smoking and having histories of diabetes and cardiovascular disease were also associated with an increased risk for vitamin D deficiency (P < 0.05). Conclusions. Among women of childbearing age, periconceptional intervention programs may focus on multiple risk factors for vitamin D deficiency and inadequacy to ultimately improve their vitamin D nutrition.

Vitamin D deficiency in pregnant women and their neonates in spring time in western Turkey

Although Turkey is located in a sunny region, vitamin D deficiency is still a serious health problem in pregnant women and their infants, especially among the low socio-economic status Turkish population. This study was carried out in order to measure serum 25-hydroxyvitamin D3 [25(OH)D] concentrations of the pregnant women in the last trimester and in their neonates at delivery and to determine the factors associated with maternal serum 25(OH)D concentrations. Among the patients visiting the Ege Obstetrics and Gynecology Hospital in the period March to May 2008, 258 healthy pregnant women ≥37 weeks of gestation were included in this study. The information on different characteristics such as the number of pregnancies and births, nutritional status, vitamin and mineral support during gestation, educational status, clothing style and the economic level of the family was collected from women. Blood samples from the mothers and umbilical cord of the newborns were taken to measure 25(OH)D. The mean 25(OH)D concentrations of the mothers and their infants were 11.5 ± 5.4 ng/mL and 11.5 ± 6.8 ng/mL, respectively. We found a strong positive correlation between maternal serum and umbilical cord blood 25(OH)D concentrations (r = 0.651, P < 0.001). The concentration of 25(OH)D was ≤20 ng/mL in 233 mothers (90.3%) and ≤10 ng/mL in 130 mothers (50.4%). Maternal serum 25(OH)D concentrations related strongly to factors such as uncovered dressing style, sufficient consumption of dairy products and multivitamin use during gestation (P < 0.05). About half (52.7%) of these women had a covered dressing style. 25(OH)D concentrations of these covered dressing mothers and their infants were 9.7 ± 5.1 ng/mL and 9.7 ± 5.6 ng/mL, respectively, which were significantly lower compared with those of uncovered mothers and their babies (P < 0.001). This study showed that, despite a sunny environment, vitamin D deficiency and insufficiency are highly prevalent among the mothers and their neonates. This is generally due to the life style and nutritional status of the mothers. These findings suggest that much more effective vitamin D prophylaxis programmes should be implemented for pregnant women as well as for their babies.

Rickets

Rickets is disorder of a growing child arising from disorders that result in impaired apoptosis of hypertrophic cells and mineralization of the growth plate. Rickets due to nutritional causes remains an important global problem. The factors responsible for resurgence of rickets among dark-skinned infants living in developed countries include the following: residence in northern or southern latitudes, voluntary avoidance of exposure to solar ultraviolet B radiation, maternal vitamin D deficiency during pregnancy, and prolonged breastfeeding without provision of vitamin D supplements. Fibroblast growth factor 23 (FGF23), secreted by osteocytes, is an important regulator of serum phosphate and 1,25(OH)(2)D(3) levels. Hypophosphatemic rickets resulting from increased synthesis or under-catabolism of FGF23 is reviewed.

Clinical practice: diagnostic approach to the rachitic child

Rickets remains a common problem among infants and children in many countries worldwide. Although the classical presentation associated with bone abnormalities is well known, paediatricians need to be aware of atypical presentations, especially in the first 6 months of life. Furthermore, although vitamin D deficiency rickets remains the commonest form of rickets in most countries, health care providers need to be aware of other possible causes and their typical clinical and biochemical presentations. This article discusses these and highlights the characteristic features of various forms of rickets and possible pitfalls clinicians should be aware of when confronted with a patient with suspected rickets. In conclusion, the recent advances made in understanding the underlying pathogeneses of the various forms of rickets has helped to delineate the diagnostic tests that assist in the diagnosis and management of the disease in children.

Prevalence of vitamin D deficiency in a North London antenatal population

OBJECTIVE

We evaluated the prevalence of vitamin D deficiency in the antenatal patients attending North Middlesex University Hospital between March 2008 and March 2009.

STUDY DESIGN

A prospective study of maternal levels of vitamin D at booking.

RESULTS

The prevalence of both deficient and insufficient levels of 25[OH]D was 87.6% across all included patients.

CONCLUSION

There is a high prevalence of asymptomatic vitamin D deficiency in the antenatal booking population.

Vitamin D: current status and perspectives

The role of vitamin D in maintaining bone health has been known for decades. Recently, however, the discovery that many tissues expressed the vitamin D receptor and were able to transform the 25-OH vitamin D into its most active metabolite, 1,25-(OH)

Clin Chem Lab Med 2009;47:120–7.

Pediatric vitamin D and calcium nutrition in developing countries

Over one billion humans have insufficient circulating levels of vitamin D, and dietary insufficiency of calcium is common in developing countries. Worldwide, nutritional rickets is considered to be the most common non-communicable disease of children. Rickets can be due either to primary deficiencies of vitamin D or calcium or to combined deficiencies of both elements. Vitamin D deficiency is also increasingly linked to non-skeletal complications. Even without laboratory and radiologic resources, the diagnosis of rickets is considered clinically when a child presents with limb deformities and has beaded ribs and widened wrists and ankles. Prevention is possible through increased sun exposure and dietary enhancement. Treatment of nutritional rickets involves provision of adequate vitamin D and calcium. Further research is needed to elucidate the precise epidemiology of vitamin D and calcium deficiencies in developing countries, to determine the roles of additional pathologic factors contributing to the development and morbidity of rickets, to improve affordable and feasible means of diagnosing rickets in resource-limited areas, to better target at-risk populations for preventive interventions, to identify accurate dosing and delivery of therapeutic interventions, and to evaluate the long-term consequences of vitamin D and calcium deficiencies in childhood.

Asthma year in review 2006-7

This review focuses on papers published between September 2006 and September 2007 that either answer important clinical questions, or signpost important areas for future research.

Inherited disorders of calcium homeostasis

In mammals a complicated homeostatic mechanism has evolved to maintain near consistency of extracellular calcium ion levels. The homeostatic mechanism involves several hormones, which comprise among others, parathyroid hormone and vitamin D. The recent resurge in vitamin D deficiency, as a global health issue, has increased interest in the hormone. In addition to vitamin D deficiency, other causes of rickets are calcium deficiency and inherited disorders of vitamin D and phosphorus metabolism. Vitamin D-resistant syndromes are caused by hereditary defects in metabolic activation of the hormone or by mutations in the vitamin D receptor, which binds the hormone with high affinity and regulates the expression of genes through zinc finger mediated DNA binding and protein-protein interaction. Current interest is to correlate the type/position of mutations that result in disorders of vitamin D metabolism or in vitamin D receptor function with the variable phenotypic features and clinical presentation. The calcium sensing receptor plays a key role in calcium homeostasis. Loss of function mutations in the calcium sensing receptor can cause familial benign hypocalciuric hypercalcemia in heterozygotes and neonatal severe hyperparathyroidism when homozygous mutations occur in the calcium sensing receptor. Gain of function mutation can cause the opposite effect causing autosomal dominant hypocalcemia. Mouse models using targeted gene disruption strategies have been valuable tools to study the effect of mutations on the calcium sensing receptor or in the vitamin D activation pathway. Dysfunctional calcium sensing receptors with function altering mutations may be responsive to treatment with allosteric modulators of the calcium sensing receptor. Vitamin D analogs which induce unusual structural conformations on the vitamin D receptor may have a variety of therapeutic indications. This review summarises recent advances in knowledge of the molecular pathology of inherited disorders of calcium homeostasis.

High prevalence of asymptomatic vitamin D and iron deficiency in East African immigrant children and adolescents living in a temperate climate

OBJECTIVES

Vitamin D deficiency (VDD) is common in immigrant children with increased skin pigmentation living in higher latitudes. We assessed the pattern of and risk factors for VDD in immigrant East African children living in Melbourne (latitude 37 degrees 49' South).

STUDY DESIGN

A prospective survey of 232 East African children attending a clinic in Melbourne. Data were collected by questionnaire, medical assessment and laboratory tests.

RESULTS

Low 25-hydroxyvitamin D (25-OHD) levels (<50 nmol/l) occurred in 87% of children, and VDD (25-OHD <25 nmol/l) in 44%. Risk factors included age <5 years, female gender, increased time in Australia, decreased daylight exposure and winter/spring season. Anaemia (20%), vitamin A deficiency (20%) and iron deficiency (19%) were also identified.

CONCLUSIONS

Asymptomatic VDD is common in East African immigrant children residing at a temperate latitude. Risk factors for VDD limit endogenous vitamin D production. Screening of immigrant children with increased skin pigmentation for VDD, anaemia, iron and vitamin A deficiency is appropriate. VDD in adolescent females identifies an increased risk of future infants with VDD.