Influence of vitamin D supplementation on growth, body composition, pubertal development and spirometry in South African schoolchildren: a randomised controlled trial (ViDiKids).

OBJECTIVE: To determine whether weekly oral vitamin D supplementation influences growth, body composition, pubertal development or spirometric outcomes in South African schoolchildren. DESIGN: Phase 3 double-blind randomised placebo-controlled trial. SETTING: Socioeconomically disadvantaged peri-urban district of Cape Town, South Africa. PARTICIPANTS: 1682 children of black African ancestry attending government primary schools and aged 6-11 years at baseline. INTERVENTIONS: Oral vitamin D3 (10 000 IU/week) versus placebo for 3 years. MAIN OUTCOME MEASURES: Height-for-age and body mass index-for-age, measured in all participants; Tanner scores for pubertal development, spirometric lung volumes and body composition, measured in a subset of 450 children who additionally took part in a nested substudy. RESULTS: Mean serum 25-hydroxyvitamin D3 concentration at 3-year follow-up was higher among children randomised to receive vitamin D versus placebo (104.3 vs 64.7 nmol/L, respectively; mean difference (MD) 39.7 nmol/L, 95% CI 37.6 to 41.9 nmol/L). No statistically significant differences in height-for-age z-score (adjusted MD (aMD) -0.08, 95% CI -0.19 to 0.03) or body mass index-for-age z-score (aMD -0.04, 95% CI -0.16 to 0.07) were seen between vitamin D versus placebo groups at follow-up. Among substudy participants, allocation to vitamin D versus placebo did not influence pubertal development scores, % predicted forced expiratory volume in 1 s (FEV1), % predicted forced vital capacity (FVC), % predicted FEV1/FVC, fat mass or fat-free mass. CONCLUSIONS: Weekly oral administration of 10 000 IU vitamin D3 boosted vitamin D status but did not influence growth, body composition, pubertal development or spirometric outcomes in South African schoolchildren. TRIAL REGISTRATION NUMBERS: ClinicalTrials.gov NCT02880982, South African National Clinical Trials Register DOH-27-0916-5527.

Influence of vitamin D supplementation on bone mineral content, bone turnover markers, and fracture risk in South African schoolchildren: multicenter double-blind randomized placebo-controlled trial (ViDiKids).

Randomized controlled trials (RCTs) to determine the influence of vitamin D on BMC and fracture risk in children of Black African ancestry are lacking. We conducted a sub-study (n = 450) nested within a phase 3 RCT of weekly oral supplementation with 10 000 IU vitamin D3 vs placebo for 3 yr in HIV-uninfected Cape Town schoolchildren aged 6-11 yr. Outcomes were BMC at the whole body less head (WBLH) and LS and serum 25-hydroxyvitamin D3 (25(OH)D3), PTH, alkaline phosphatase, C-terminal telopeptide, and PINP. Incidence of fractures was a secondary outcome of the main trial (n = 1682). At baseline, mean serum 25(OH)D3 concentration was 70.0 nmol/L (SD 13.5), and 5.8% of participants had serum 25(OH)D3 concentrations <50 nmol/L. Among sub-study participants, end-trial serum 25(OH)D3 concentrations were higher for participants allocated to vitamin D vs placebo (adjusted mean difference [aMD] 39.9 nmol/L, 95% CI, 36.1 to 43.6) and serum PTH concentrations were lower (aMD -0.55 pmol/L, 95% CI, -0.94 to -0.17). However, no interarm differences were seen for WBLH BMC (aMD -8.0 g, 95% CI, -30.7 to 14.7) or LS BMC (aMD -0.3 g, 95% CI, -1.3 to 0.8) or serum concentrations of bone turnover markers. Fractures were rare among participants in the main trial randomized to vitamin D vs placebo (7/755 vs 10/758 attending at least 1 follow-up; adjusted odds ratio 0.70, 95% CI, 0.27 to 1.85). In conclusion, a 3-yr course of weekly oral vitamin D supplementation elevated serum 25(OH)D3 concentrations and suppressed serum PTH concentrations in HIV-uninfected South African schoolchildren of Black African ancestry but did not influence BMC or serum concentrations of bone turnover markers. Fracture incidence was low, limiting power to detect an effect of vitamin D on this outcome.

Vitamin D­the "sunshine vitamin"­is essential for helping the body to absorb calcium from the diet, which is laid down in bone to improve its strength. There is a lack of clinical trials testing whether vitamin D supplements can improve bone content of calcium and other minerals, or reduce risk of bone fractures (broken bones) in children of Black African ancestry. We therefore conducted such a study, recruiting 1682 schoolchildren aged 6­11 yr living in Cape Town, South Africa. We found that a weekly dose of 10 000 international units (250 micrograms) of vitamin D3, given by mouth for 3 yr, was effective in boosting vitamin D levels in trial participants who received it. However, this did not have any effect on bone content of calcium and other minerals. Relatively few children experienced a broken bone during the study, so we were unable to say with confidence whether or not vitamin D supplements might affect this outcome.

The effect of pregnancy vitamin D supplementation on offspring bone mineral density in childhood: a systematic review and meta-analysis.

Systematic review and meta-analysis of the effect of moderate- to high-dose vitamin D supplementation in pregnancy on offspring bone mineralisation found a positive effect of vitamin D supplementation on offspring bone mineral density (BMD) at age 4-6 years, with a smaller effect on bone mineral content. PURPOSE: A systematic review and meta-analysis was performed to assess the effect of pregnancy vitamin D supplementation on offspring bone mineral density (BMD) in childhood. METHODS: A literature search was conducted for published RCTs of antenatal vitamin D supplementation with assessment of offspring BMD or bone mineral content (BMC) by dual-energy X-ray absorptiometry (DXA) using MEDLINE and EMBASE up to 13th July 2022. Risk of bias was assessed using the Cochrane Risk of Bias 2 tool. Study findings were grouped in two age groups of offspring assessment: neonatal period and early childhood (3-6 years). Random-effects meta-analysis of the effect on BMC/BMD at 3-6 years was performed using RevMan 5.4.1, yielding standardised mean difference (SMD) (95% CI). RESULTS: Five RCTs were identified with offspring assessment of BMD or BMC; 3250 women were randomised within these studies. Risk of bias was low in 2 studies and "of concern" in 3. Supplementation regimes and the control used (3 studies used placebo and 2 used 400 IU/day cholecalciferol) varied, but in all studies the intervention increased maternal 25-hydroxvitamin D status compared to the control group. Two trials assessing BMD in the neonatal period (total n = 690) found no difference between groups, but meta-analysis was not performed as one trial represented 96.4% of those studied at this age. Three trials assessed offspring whole-body-less-head BMD at age 4-6 years. BMD was higher in children born to mothers supplemented with vitamin D [0.16 SD (95% confidence interval 0.05, 0.27), n = 1358] with a smaller effect on BMC [0.07 SD (95% CI - 0.04, 0.19), n = 1351]. CONCLUSIONS: There are few RCTs published to address this question, and these are inconsistent in methodology and findings. However, meta-analysis of three trials suggests moderate- to high-dose vitamin D supplementation in pregnancy might increase offspring BMD in early childhood, but further trials are required to confirm this finding. (Prospero CRD42021288682; no funding received).

Does antenatal cholecalciferol supplementation affect the mode or timing of delivery? Post hoc analyses of the MAVIDOS randomized controlled trial.

BACKGROUND: Observational studies relating maternal 25-hydroxyvitamin D status to timing and mode of delivery have reported inconsistent results. We assessed the effect of antenatal cholecalciferol supplementation on the incidence of preterm birth, delivery mode and post-partum haemorrhage (PPH). METHODS: MAVIDOS was a randomized, double-blind, placebo-controlled trial of 1000 IU/day cholecalciferol from 14 weeks' gestation until delivery. Gestational age, mode of delivery [categorized as spontaneous vaginal delivery (SVD), instrumental (including forceps and vacuum extraction) or Caesarean section] and PPH (>500 ml estimated blood loss) were determined from medical records. RESULTS: A total of 965 women participated in the study until delivery. Gestation at birth and incidence of preterm birth (cholecalciferol 5.7%, placebo 4.5%, P = 0.43) were similar between the two treatment groups. SVD (versus instrumental or Caesarean delivery) was more likely in women randomized to cholecalciferol [Relative Risk (RR) 1.13, 95% confidence interval (CI) 1.02,1.25] due to lower instrumental (RR 0.68, 95%CI 0.51,0.91) but similar risk of Caesarean delivery (RR 0.94, 95%CI 0.74,1.19). PPH was less common in women randomized to cholecalciferol [32.1% compared with placebo (38.1%, P = 0.054) overall], but similar when stratified by delivery mode. CONCLUSIONS: Antenatal cholecalciferol supplementation did not alter timing of birth or prevalence of preterm birth but demonstrated a possible effect on the likelihood of SVD.

Role of vitamin D supplementation in the management of musculoskeletal diseases: update from an European Society of Clinical and Economical Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO) working group.

Vitamin D is a key component for optimal growth and for calcium-phosphate homeostasis. Skin photosynthesis is the main source of vitamin D. Limited sun exposure and insufficient dietary vitamin D supply justify vitamin D supplementation in certain age groups. In older adults, recommended doses for vitamin D supplementation vary between 200 and 2000 IU/day, to achieve a goal of circulating 25-hydroxyvitamin D (calcifediol) of at least 50 nmol/L. The target level depends on the population being supplemented, the assessed system, and the outcome. Several recent large randomized trials with oral vitamin D regimens varying between 2000 and 100,000 IU/month and mostly conducted in vitamin D-replete and healthy individuals have failed to detect any efficacy of these approaches for the prevention of fracture and falls. Considering the well-recognized major musculoskeletal disorders associated with severe vitamin D deficiency and taking into account a possible biphasic effects of vitamin D on fracture and fall risks, an European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO) working group convened, carefully reviewed, and analyzed the meta-analyses of randomized controlled trials on the effects of vitamin D on fracture risk, falls or osteoarthritis, and came to the conclusion that 1000 IU daily should be recommended in patients at increased risk of vitamin D deficiency. The group also addressed the identification of patients possibly benefitting from a vitamin D loading dose to achieve early 25-hydroxyvitamin D therapeutic level or from calcifediol administration.

Pregnancy Vitamin D Supplementation and Childhood Bone Mass at Age 4 Years: Findings From the Maternal Vitamin D Osteoporosis Study (MAVIDOS) Randomized Controlled Trial.

In the Maternal Vitamin D Osteoporosis Study (MAVIDOS) randomized trial, vitamin D supplementation in pregnancy did not lead to greater neonatal bone mass across the trial as a whole, but, in a prespecified secondary analysis by season of birth, led to greater neonatal bone mass among winter-born babies. Demonstrating persistence of this effect into childhood would increase confidence in a long-term benefit of this intervention. We investigated whether antenatal vitamin D supplementation increases offspring bone mineralization in early childhood in a prespecified, single-center follow-up of a double-blinded, multicenter, randomized controlled clinical trial based in the UK (MAVIDOS). A total of 1123 women in early pregnancy with a baseline 25-hydroxyvitamin D level 25-100 nmol/L from three research centers (2008-2014) were randomized to 1000 IU/d cholecalciferol or matched placebo from 14 weeks of gestation to delivery. Offspring born at the Southampton, UK research center were assessed at age 4 years (2013-2018). Anthropometry and dual-energy X-ray absorptiometry (DXA) were performed (yielding whole body less head [WBLH] bone mineral content [BMC], areal bone mineral density [aBMD], bone area [BA], and body composition). Of 723 children, 564 (78.0%) children attended the 4-year visit, 452 of whom had a useable DXA. Maternal vitamin D supplementation led to greater WBLH aBMD in the children compared with placebo (mean [95% confidence interval {CI}]: supplemented group: 0.477 (95% CI, 0.472-0.481) g/cm2; placebo group: 0.470 (95% CI, 0.466-0.475) g/cm2, p = 0.048). Associations were consistent for BMC and lean mass, and in age- and sex-adjusted models. Effects were observed across the whole cohort irrespective of season of birth. Maternal-child interactions were observed, with a greater effect size among children with low milk intake and low levels of physical activity. Child weight, height, and body mass index (BMI) were similar by maternal randomization group. These findings suggest a sustained beneficial effect of maternal vitamin D supplementation in pregnancy on offspring aBMD at age 4 years, but will require replication in other trials. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Maternal antenatal vitamin D supplementation and offspring risk of atopic eczema in the first 4 years of life: evidence from a randomized controlled trial.

BACKGROUND: Evidence linking prenatal maternal vitamin D supplementation with the offspring's risk of atopic eczema is inconsistent, with most data coming from observational studies. OBJECTIVES: To examine the influence of maternal cholecalciferol supplementation during pregnancy on the risk of atopic eczema in the offspring at ages 12, 24 and 48 months. METHODS: Within the UK Maternal Vitamin D Osteoporosis Study (MAVIDOS) double-blind, randomized placebo-controlled trial, we examined the relationship of maternal vitamin D supplementation during pregnancy with offspring atopic eczema at ages 12, 24 and 48 months. In MAVIDOS, pregnant women were allocated to either cholecalciferol 1000 IU per day or matched placebo, taken from around 14 weeks' gestation until delivery, with the primary outcome of neonatal whole-body bone mineral content. The prevalence of atopic eczema in the offspring was ascertained at ages 12 (n = 635), 24 (n = 610) and 48 (n = 449) months, based on the UK Working Party criteria for the definition of atopic dermatitis. The trial was registered with ISRCTN (82927713) and EudraCT (2007-001716-23). RESULTS: The characteristics of mothers and offspring were similar between the intervention and placebo groups, apart from longer breastfeeding duration in the intervention group. Adjusting for breastfeeding duration, offspring of mothers who received cholecalciferol 1000 IU daily had a lower odds ratio (OR) of atopic eczema at age 12 months [OR 0·55, 95% confidence interval (CI) 0·32-0·97, P = 0·04]; this effect weakened and was not statistically significant at ages 24 months (OR 0·76, 95% CI 0·47-1·23) or 48 months (OR 0·75, 95% CI 0·37-1·52). The statistical interaction of intervention and breastfeeding duration in relation to eczema at age 12 months was not significant (P = 0·41), but stratification showed reduced infantile eczema risk in the intervention group for infants breastfed for ≥ 1 month (OR 0·48, 95% CI 0·24-0·94, P = 0·03) but not in those breastfed for < 1 month (OR 0·80, 95% CI 0·29-2·17, P = 0·66). CONCLUSIONS: Our data provide the first randomized controlled trial evidence of a protective effect of antenatal cholecalciferol supplementation on the risk of infantile atopic eczema, with the effect potentially being via increased breast milk cholecalciferol levels. The findings support a developmental influence on atopic eczema, and point to a potentially modifiable perinatal influence on atopic eczema. What is already known about this topic? There are currently no antenatal interventions proven to reduce the incidence of infantile atopic eczema in the general population. However, observational studies have led to speculation that antenatal vitamin D supplementation may be beneficial.

Early life vitamin D depletion and mechanical loading determine methylation changes in the RUNX2, RXRA, and osterix promoters in mice.

BACKGROUND: Early life vitamin D exposure is linked to later skeletal health with maternal vitamin D status in pregnancy associated with neonatal bone mass. The MAVIDOS study has demonstrated that vitamin D supplementation leads to reduced RXRA DNA methylation. Mice exposed to early life vitamin D deficiency have reduced bone mass and bone accrual in response to mechanical loading. Using the tibiae of these mice, we have examined the effect of diet and mechanical loading on the DNA methylation of promoters of genetic loci important for bone growth and development and their association with bone strength. RESULTS: Mechanical loading of mouse tibiae leads to a reduction of RXRA DNA methylation. Early life vitamin D deficiency is associated with altered methylation of osterix and Runx2 in these bones. Tibia strength was also demonstrated to be associated with a change in DNA methylation status in CpGs of the vitamin D receptor (VDR), ostrix, and RXRA genes. CONCLUSIONS: We have shown for the first time that mechanical loading of bone and early life vitamin D deficiency leads to changes in the epigenome of this tissue in key genes in the vitamin D and osteoblast differentiation pathway.

Maternal and Fetal Genetic Variation in Vitamin D Metabolism and Umbilical Cord Blood 25-Hydroxyvitamin D.

CONTEXT: Single nucleotide polymorphisms (SNPs) in vitamin D metabolism pathway genes are associated with circulating 25-hydroxyvitamin D (25(OH)D) in adults. Less is known about the relationships between mother and offspring SNPs and umbilical cord blood 25(OH)D. OBJECTIVE: (1) To undertake a meta-analysis of the relationships of maternal and offspring SNPs in the vitamin D metabolism pathway and cord blood 25(OH)D in pregnant women including novel data; and (2) to examine these relationships in women who received antenatal cholecalciferol supplementation in a clinical trial. METHODS: Novel data analysis from an observational mother-offspring cohort study (Southampton Women's Survey) and the MAVIDOS double-blind, randomized, placebo-controlled trial of 1000 IU/day cholecalciferol supplementation in pregnancy, and an electronic literature search of published studies in PubMed up to 31 July 2021. Studies reporting associations between rs12785878 (DHCR7), rs10741657 (CYP2R1), rs6013897 (CYP24A1), or rs2282679 (GC) and cord blood 25(OH)D. One published study was included in addition to the novel data analysis. Associations between both maternal and offspring SNPs at rs2282679 (GC) and rs12785878 (DHCR7), and cord blood 25(OH)D were identified. When maternal genotype was adjusted for offspring genotype, and vice versa, there was persisting evidence for associations with maternal rs12785878 (ß [95% CI] 1.6 nmol/L [0.3, 2.8] per common allele), and offspring rs2282679 (ß 3.1 nmol/L ]2.0, 4.4] per common allele). Maternal and offspring SNPs at rs1074657 and rs613897 were not associated with cord blood 25(OH)D. RESULT: Associations between both maternal and offspring SNPs at rs2282679 (GC) and rs12785878 (DHCR7), and cord blood 25(OH)D were identified. When maternal genotype was adjusted for offspring genotype, and vice versa, there was persisting evidence for associations with maternal rs12785878 (ß [95% CI] 1.6 nmol/L [0.3, 2.8] per common allele), and offspring rs2282679 (ß 3.1 nmol/L ]2.0, 4.4] per common allele). Maternal and offspring SNPs at rs1074657 and rs613897 were not associated with cord blood 25(OH)D. CONCLUSION: Common genetic variation in the vitamin D metabolism pathway is associated with umbilical cord blood 25(OH)D.

Interdisciplinary management of FGF23-related phosphate wasting syndromes: a Consensus Statement on the evaluation, diagnosis and care of patients with X-linked hypophosphataemia.

X-linked hypophosphataemia (XLH) is the most frequent cause of hypophosphataemia-associated rickets of genetic origin and is associated with high levels of the phosphaturic hormone fibroblast growth factor 23 (FGF23). In addition to rickets and osteomalacia, patients with XLH have a heavy disease burden with enthesopathies, osteoarthritis, pseudofractures and dental complications, all of which contribute to reduced quality of life. This Consensus Statement presents the outcomes of a working group of the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases, and provides robust clinical evidence on management in XLH, with an emphasis on patients' experiences and needs. During growth, conventional treatment with phosphate supplements and active vitamin D metabolites (such as calcitriol) improves growth, ameliorates leg deformities and dental manifestations, and reduces pain. The continuation of conventional treatment in symptom-free adults is still debated. A novel therapeutic approach is the monoclonal anti-FGF23 antibody burosumab. Although promising, further studies are required to clarify its long-term efficacy, particularly in adults. Given the diversity of symptoms and complications, an interdisciplinary approach to management is of paramount importance. The focus of treatment should be not only on the physical manifestations and challenges associated with XLH and other FGF23-mediated hypophosphataemia syndromes, but also on the major psychological and social impact of the disease.

Immune-endocrine biomarkers associated with mental health: A 9-year longitudinal investigation from the Hertfordshire Ageing Study.

BACKGROUND: The study of neural-endocrine-immune system interactions has led to substantial advances in our understanding of neuropsychiatric disorders. Growing evidence reveals the pivotal roles of inflammatory cytokines signalling the brain to produce neurochemical, neuroendocrine, and neuroimmune changes which affect mood and behaviour. Ageing is accompanied by the development of low-grade systemic inflammation which may promote changes in the neural systems predisposing to geriatric depression via the hypothalamic-pituitary-adrenal (HPA) axis. The aim of this study was to investigate the longitudinal associations between baseline values and conditional changes (independent of baseline) in immune-endocrine biomarkers and mental health status in a population-based cohort of older adults. METHODS: Data from 347 subjects (200 men, 147 women) who participated in the Hertfordshire Ageing Study at baseline (1994/5, mean age 67.3 years) and at 9-year follow-up were analysed. Serum samples for analysis of inflammatory and endocrinological measures were collected at baseline and follow-up. At follow-up, depression (Hospital Anxiety and Depression Scale) and mental health (Short Form-36 questionnaire) were assessed. Baseline values and changes in biomarkers in relation to risk of high depression scores (top sex-specific third) and low mental health scores (bottom sex-specific third) were examined using logistic regression. RESULTS: Lower baseline cortisol was related to greater risk of high depression scores; higher baseline cortisol: dehydroepiandrosterone sulphate ratio (men only) and higher baseline C-reactive protein (CRP) (women only) were related to greater risk of poor mental health scores. In addition, greater decline in cortisol was related to increased risk of high depression scores among men. These relationships were robust (p < 0.05) after controlling for sex, age, BMI, smoking, alcohol consumption and number of systems medicated. CONCLUSION: This study provides further evidence of the role of the HPA axis and inflammation in older adults with poor mental health. In addition, the findings highlight sex differences where increased inflammation in women and declines in cortisol in men were linked to poorer mental health. Further research is warranted to confirm these findings. This could lead to the search for potential biomarkers to stratify medications as well as developing novel intervention targets to improve mental health at older age.

Determinants of circulating 25-hydroxyvitamin D concentration and its association with musculoskeletal health in midlife: Findings from the Hertfordshire Cohort Study.

INTRODUCTION: Several studies have reported the importance of vitamin D status to musculoskeletal health in populations of older adults. Here we report relationships between circulating serum 25(OH)D and musculoskeletal health in a community cohort of UK adults in midlife and investigate whether environmental (dietary intake, use of supplements) and/or genetic factors (4 SNPs previously related to vitamin D status) play more significant roles in determining vitamin D status in this population. METHODS: Participants were recruited from the Hertfordshire Cohort Study, an established longitudinal cohort study of community dwelling adults and were seen at baseline and follow up 9-12 years later. Lumbar spine and total femur BMD were measured at baseline using a Hologic QDR 4500 instrument. Osteoarthritis (OA) was defined by radiographs of the knees graded according to Kellgren & Lawrence at both time points. Serum 25(OH)D concentrations were measured using a DiaSorin Liaison chemiluminescent assay. Genotyping of 4 SNPs previously associated with 25(OH)D values were assessed: (rs12785878 (DHCR7), rs10741657 (CYP2R1) and rs6013897 (CYP24A1)) and a fourth SNP (rs4588), described as "a near-perfect proxy (i.e. substitute) for rs2282679 on the GC gene". RESULTS: 820 subjects (397 men, 423 women) participated at baseline, and 339 of these 820 subjects (164 men; 175 women) participated in a follow up study of OA progression. The median (IQR) age of participants at baseline was 64.0 (61.8-66.5) and 65.5 (63.3-67.6) for men and women respectively. Median circulating levels of 25(OH)D were 44.6 (35.0-63.0) nmol/L and 41.3 (29.8-53.5) nmol/L in men and women respectively. Circulating 25(OH)D was strongly associated with season of blood testing (p < 0.001). The greatest variance in a model of vitamin D status that included the four SNPs measured, season, and whether participants reported taking vitamin D supplements was explained by season of assay (17.9% men; 15.8% women). Higher femoral neck BMD was observed in men with higher baseline vitamin D status, after adjustment for age, season, BMI, smoker status, alcohol consumption, physical activity and social class (p = 0.01). Associations between 25(OH)D and BMD in women were not statistically significant in this population. There were no associations between circulating 25(OH)D and radiographic knee OA at either time point after adjustment for confounders and for duration of follow-up. CONCLUSION: Circulating 25(OH)D levels were generally lower than is recommended in community dwelling adults in midlife, with marked seasonal variation observed, but relationships with reported vitamin D supplementation were weaker. Circulating 25(OH)D was directly associated with hip BMD in men but relationships with BMD in women and radiographic OA were not seen in this sample.

Bone turnover in pregnancy, measured by urinary CTX, is influenced by vitamin D supplementation and is associated with maternal bone health: findings from the Maternal Vitamin D Osteoporosis Study (MAVIDOS) trial.

BACKGROUND: The pattern of change in maternal bone turnover throughout pregnancy is poorly characterized. OBJECTIVES: We investigated changes across pregnancy in a marker of maternal bone resorption, urinary C-terminal telopeptide of type I collagen (CTX), the influence of gestational vitamin D supplementation, and associations between CTX and maternal postnatal bone indices. METHODS: MAVIDOS (the Maternal Vitamin D Osteoporosis Study) is a randomized, double-blind, placebo-controlled trial of 1000 IU cholecalciferol/d compared with placebo from 14 weeks of gestation to birth. Maternal second-void urinary α- and ß-CTX were measured (ELISA) at 14 and 34 weeks of gestation; DXA was performed within 2 wk postpartum. The Mann-Whitney Rank Sum test, Spearman's rank correlation, and linear regression were used to compare median CTX values within and between groups from early to late pregnancy, and associations with maternal bone outcomes. RESULTS: In total, 372 women had CTX and 25-hydroxyvitamin D [25(OH)D] measured in early and late pregnancy. CTX at 14 and 34 weeks of gestation were correlated in both placebo (r = 0.31) and cholecalciferol (r = 0.45) groups (P < 0.0001). Median CTX increased from 14 to 34 weeks of gestation in both groups (n = 372 total) [placebo (n = 188): from 223.6 to 449.7 µg/mmol creatinine; cholecalciferol (n = 184): from 222.3 to 419.3 µg/mmol creatinine; P = 0.03 for placebo compared with cholecalciferol difference in CTX at 34 weeks of gestation]. The conditional mean ± SD increase in CTX [z-score (SD)] from early to late pregnancy was greater in the placebo group (n = 188) than in the cholecalciferol group (n = 184) (placebo: 0.16 ± 0.92; cholecalciferol: -0.16 ± 1.06; P-difference < 0.01). Higher CTX at 34 weeks of gestation was associated, similarly in both groups, with lower maternal total hip and lumbar spine bone mineral content and bone mineral density (BMD) (e.g., lumbar spine BMD: ß = -0.02 g · cm-2 · SD-1 increase in CTX; 95% CI: -0.027, -0.002 g · cm-2 · SD-1; P = 0.02, n = 283). CONCLUSIONS: Maternal urinary CTX, a bone resorption marker, rises through pregnancy, although to a lesser degree with gestational cholecalciferol supplementation, and is inversely associated with maternal bone mass postpartum.This trial was registered at www.isrctn.com as ISRCTN 82927713 and eudract.ema.europa.eu as EudraCT 2007-001716-23.

Vitamin D and coronavirus disease 2019 (COVID-19): rapid evidence review.

BACKGROUND: The rapid global spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID-19), has re-ignited interest in the possible role of vitamin D in modulation of host responses to respiratory pathogens. Indeed, vitamin D supplementation has been proposed as a potential preventative or therapeutic strategy. Recommendations for any intervention, particularly in the context of a potentially fatal pandemic infection, should be strictly based on clinically informed appraisal of the evidence base. In this narrative review, we examine current evidence relating to vitamin D and COVID-19 and consider the most appropriate practical recommendations. OBSERVATIONS: Although there are a growing number of studies investigating the links between vitamin D and COVID-19, they are mostly small and observational with high risk of bias, residual confounding, and reverse causality. Extrapolation of molecular actions of 1,25(OH)2-vitamin D to an effect of increased 25(OH)-vitamin D as a result of vitamin D supplementation is generally unfounded, as is the automatic conclusion of causal mechanisms from observational studies linking low 25(OH)-vitamin D to incident disease. Efficacy is ideally demonstrated in the context of adequately powered randomised intervention studies, although such approaches may not always be feasible. CONCLUSIONS: At present, evidence to support vitamin D supplementation for the prevention or treatment of COVID-19 is inconclusive. In the absence of any further compelling data, adherence to existing national guidance on vitamin D supplementation to prevent vitamin D deficiency, predicated principally on maintaining musculoskeletal health, appears appropriate.

The importance of maternal pregnancy vitamin D for offspring bone health: learnings from the MAVIDOS trial.

Optimisation of skeletal mineralisation in childhood is important to reduce childhood fracture and the long-term risk of osteoporosis and fracture in later life. One approach to achieving this is antenatal vitamin D supplementation. The Maternal Vitamin D Osteoporosis Study is a randomised placebo-controlled trial, the aim of which was to assess the effect of antenatal vitamin D supplementation (1000 IU/day cholecalciferol) on offspring bone mass at birth. The study has since extended the follow up into childhood and diversified to assess demographic, lifestyle and genetic factors that determine the biochemical response to antenatal vitamin D supplementation, and to understand the mechanisms underpinning the effects of vitamin D supplementation on offspring bone development, including epigenetics. The demonstration of positive effects of maternal pregnancy vitamin D supplementation on offspring bone development and the delineation of underlying biological mechanisms inform clinical care and future public-health policies.

Cardiovascular safety of calcium, magnesium and strontium: what does the evidence say?

Calcium, magnesium and strontium have all been implicated in both musculoskeletal and cardiovascular health and disease. However, despite these three elements being closely chemically related, there is marked heterogeneity of their characteristics in relation to cardiovascular outcomes. In this narrative review, we describe the relevant evidential landscape, focusing on clinical trials where possible and incorporating findings from observational and causal analyses, to discern the relative roles of these elements in musculoskeletal and cardiovascular health. We conclude that calcium supplementation (for bone health) is most appropriately used in combination with vitamin D supplementation and targeted to those who are deficient in these nutrients, or in combination with antiosteoporosis medications. Whilst calcium supplementation is associated with gastrointestinal side effects and a small increased risk of renal stones, purported links with cardiovascular outcomes remain unconvincing. In normal physiology, no mechanism for an association has been elucidated and other considerations such as dose response and temporal relationships do not support a causal relationship. There is little evidence to support routine magnesium supplementation for musculoskeletal outcomes; greater dietary intake and serum concentrations appear protective against cardiovascular events. Strontium ranelate, which is now available again as a generic medication, has clear anti-fracture efficacy but is associated with an increased risk of thromboembolic disease. Whilst a signal for increased risk of myocardial infarction has been detected in some studies, this is not supported by wider analyses. Strontium ranelate, under its current licence, thus provides a useful therapeutic option for severe osteoporosis in those who do not have cardiovascular risk factors.

2019 EULAR points to consider for non-physician health professionals to prevent and manage fragility fractures in adults 50 years or older.

OBJECTIVE: To establish European League Against Rheumatism (EULAR) points to consider for non-physician health professionals to prevent and manage fragility fractures in adults 50 years or older. METHODS: Points to consider were developed in accordance with EULAR standard operating procedures for EULAR-endorsed recommendations, led by an international multidisciplinary task force, including patient research partners and different health professionals from 10 European countries. Level of evidence and strength of recommendation were determined for each point to consider, and the mean level of agreement among the task force members was calculated. RESULTS: Two overarching principles and seven points to consider were formulated based on scientific evidence and the expert opinion of the task force. The two overarching principles focus on shared decisions between patients and non-physician health professionals and involvement of different non-physician health professionals in prevention and management of fragility fractures. Four points to consider relate to prevention: identification of patients at risk of fracture, fall risk evaluation, multicomponent interventions to prevent primary fracture and discouragement of smoking and overuse of alcohol. The remaining three focus on management of fragility fractures: exercise and nutritional interventions, the organisation and coordination of multidisciplinary services for post-fracture models of care and adherence to anti-osteoporosis medicines. The mean level of agreement among the task force for the overarching principles and the points to consider ranged between 8.4 and 9.6. CONCLUSION: These first EULAR points to consider for non-physician health professionals to prevent and manage fragility fractures in adults 50 years or older serve to guide healthcare practice and education.

Maternal pregnancy vitamin D supplementation increases offspring bone formation in response to mechanical loading: Findings from a MAVIDOS Trial sub-study.

The Maternal Vitamin D Osteoporosis (MAVIDOS) trial reported higher total body bone mineral content in winter-born infants of mothers receiving vitamin D supplementation [1000 IU/day cholecalciferol] compared with placebo from 14 weeks gestation until delivery. This sub-study aimed to determine whether antenatal vitamin D supplementation altered postnatal bone formation in response to mechanical stimulation. Thirty-one children born to MAVIDOS participants randomised to either placebo (n=19) or cholecalciferol (n=12) were recruited at age 4-5 years. Children received whole body vibration (WBV) for 10 minutes on 5 consecutive days. Fasting blood samples for bone homeostasis, 25 hydroxyvitamin D (25OHD), parathyroid hormone (PTH), and bone turnover markers (Pro-collagen Type 1 N-terminal propeptide, P1NP; Cross-linked C-telopeptide of Type I Collagen, CTX) were collected pre-WBV and on day 8 (D8). Mean changes (D) in P1NP (ng/ml) between baseline and D8 in the vitamin-D intervention and placebo groups were 40.6 and -92.6 respectively and mean changes (Δ) in CTX (ng/ml) were 0.034 (intervention) and -0.084 (placebo) respectively. Between-group DP1NP difference was 133.2ng/ml [95% CI 0.4, 266.0; p=0.049] and ΔCTX 0.05ng/ml (95% CI -0.159, 0.26ng/mL; p=0.62). Antenatal vitamin-D supplementation resulted in increased P1NP in response to WBV, suggesting early life vitamin D supplementation increases the anabolic response of bone to mechanical loading in children.

Prevention and management of osteoporotic fractures by non-physician health professionals: a systematic literature review to inform EULAR points to consider.

OBJECTIVE: To perform a systematic literature review (SLR) about the effect of non-pharmacological interventions delivered by non-physician health professionals to prevent and manage osteoporotic fractures. METHODS: Eight clinical questions based on two criteria guided the SLR: (1) adults≥50 years at high risk of osteoporotic fracture and (2) interventions delivered by non-physician health professionals to prevent and manage osteoporotic fractures. Interventions focused on diagnostic procedures to identify risk of falling, therapeutic approaches and implementation strategies. Outcomes included fractures, falls, risk of falling and change in bone mineral density. Systematic reviews and randomised controlled trials were preferentially selected. Data were synthesised using a qualitative descriptive approach. RESULTS: Of 15 917 records, 43 articles were included. Studies were clinically and methodologically diverse. We identified sufficient evidence that structured exercise, incorporating progressive resistance training delivered to people who had undergone hip fracture surgery, and multicomponent exercise, delivered to people at risk of primary fracture, reduced risk of falling. The effectiveness of multidisciplinary fracture liaison services in reducing refracture rate was confirmed. There was insufficient evidence found to support the effectiveness of nutrients and falls prevention programmes in this patient population. CONCLUSION: Despite study heterogeneity, our SLR showed beneficial effects of some interventions delivered by non-physician health professionals and the positive impact of multidisciplinary team working and patient educational approaches to prevent and manage osteoporotic fractures. These results informed a EULAR taskforce that developed points to consider for non-physician health professionals to prevent and manage osteoporotic fractures.