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1.
J Public Health (Oxf) ; 45(3): 738-747, 2023 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-36585903

RESUMO

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.


Assuntos
Cesárea , Nascimento Prematuro , Gravidez , Feminino , Recém-Nascido , Humanos , Cesárea/efeitos adversos , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/prevenção & controle , Colecalciferol/uso terapêutico , Parto Obstétrico , Suplementos Nutricionais
2.
JBMR Plus ; 6(7): e10651, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35866154

RESUMO

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.

3.
Am J Clin Nutr ; 114(5): 1600-1611, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34297067

RESUMO

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.


Assuntos
Densidade Óssea , Remodelação Óssea , Colágeno Tipo I/urina , Peptídeos/urina , Vitamina D/administração & dosagem , Adulto , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Recém-Nascido , Gravidez , Vitamina D/análogos & derivados , Vitamina D/sangue
4.
J Bone Miner Res ; 34(2): 231-240, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30321476

RESUMO

We have previously demonstrated inverse associations between maternal 25(OH)-vitamin D status and perinatal DNA methylation at the retinoid-X-receptor-alpha (RXRA) locus and between RXRA methylation and offspring bone mass. In this study, we used an existing randomized trial to test the hypothesis that maternal gestational vitamin D supplementation would lead to reduced perinatal RXRA locus DNA methylation. The Maternal Vitamin D Osteoporosis Study (MAVIDOS) was a multicenter, double-blind, randomized, placebo-controlled trial of 1000 IU/day cholecalciferol or matched placebo from 14 weeks' gestation until delivery. Umbilical cord (fetal) tissue was collected at birth and frozen at -80°C (n = 453). Pyrosequencing was used to undertake DNA methylation analysis at 10 CpG sites within the RXRA locus (identified previously). T tests were used to assess differences between treatment groups in methylation at the three most representative CpG sites. Overall, methylation levels were significantly lower in the umbilical cord from offspring of cholecalciferol-supplemented mothers, reaching statistical significance at four CpG sites, represented by CpG5: mean difference in % methylation between the supplemented and placebo groups was -1.98% (95% CI, -3.65 to -0.32, p = 0.02). ENCODE (Encyclopedia of DNA Elements) evidence supports the functionality of this locus with strong DNase hypersensitivity and enhancer chromatin within biologically relevant cell types including osteoblasts. Enrichment of the enhancer-related H3K4me1 histone mark is also seen in this region, as are binding sites for a range of transcription factors with roles in cell proliferation, response to stress, and growth factors. Our findings are consistent with previous observational results and provide new evidence that maternal gestational supplementation with cholecalciferol leads to altered perinatal epigenetic marking, informing mechanistic understanding of early life mechanisms related to maternal vitamin D status, epigenetic marks, and bone development. © 2018 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals Inc.


Assuntos
Ilhas de CpG , Metilação de DNA/efeitos dos fármacos , Suplementos Nutricionais , Loci Gênicos , Receptor X Retinoide alfa , Vitamina D/análogos & derivados , Adulto , Método Duplo-Cego , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Receptor X Retinoide alfa/genética , Receptor X Retinoide alfa/metabolismo , Vitamina D/administração & dosagem
5.
Clin J Gastroenterol ; 11(5): 396-400, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29680980

RESUMO

Bezoars are intra-luminal concretions of ingested material which accumulate within the bowel. They are termed pharmacobezoars when the constituent material is drugs. We report a 64-year-old female with abdominal pain and obstipation for 3 days. Patient had completed anti-tuberculous combination therapy for suspected abdominal tuberculosis 25 years ago. She exhibited features of shock with a right iliac fossa lump. Abdominal X-ray displayed multiple air-fluid levels with densely cluttered radio-opacities in the right lower quadrant. Laparotomy revealed a palpable mid-ileal intra-luminal lump, adherent to the ascending colon and proximal ileum necessitating resection. Ex vivo examination of resected specimen revealed numerous tablets aggregating proximal to an ileal stricture. The patient post-operatively confirmed the tablets resembled the herbal laxatives she had been consuming. Pharmacobezoars can lead to subacute intestinal obstruction. Numerous drugs have been implicated. Patients with partial gastrectomy and vagotomy are at risk. CT is the pre-eminent diagnostic modality. The treatment options for pharmacobezoars include lavage, endoscopic retrieval, in addition to surgery. Pharmacobezoars need a high index of suspicion for pre-operative diagnosis. A detailed history and correlation with radioimaging can offer important cues. One can prevent pharmacobezoars by abstaining from unwarranted medications and identifying those at risk.


Assuntos
Bezoares/complicações , Doenças do Íleo/etiologia , Obstrução Intestinal/etiologia , Laxantes/efeitos adversos , Preparações de Plantas/efeitos adversos , Dor Abdominal/etiologia , Bezoares/patologia , Bezoares/cirurgia , Constipação Intestinal/etiologia , Feminino , Humanos , Doenças do Íleo/cirurgia , Obstrução Intestinal/cirurgia , Pessoa de Meia-Idade , Comprimidos
6.
J Clin Endocrinol Metab ; 102(8): 2941-2949, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28575224

RESUMO

Context: Single-nucleotide polymorphisms (SNPs) in genes related to vitamin D metabolism have been associated with serum 25-hydroxyvitamin D [25(OH)D] concentration, but these relationships have not been examined following antenatal cholecalciferol supplementation. Objective: To determine whether SNPs in DHCR7, CYP2R1, CYP24A1, and GC are associated with the response to gestational cholecalciferol supplementation. Design: Within-randomization group analysis of the Maternal Vitamin D Osteoporosis Study trial of antenatal cholecalciferol supplementation. Setting: Hospital antenatal clinics. Participants: In total, 682 women of white ethnicity (351 placebo, 331 cholecalciferol) were included. SNPs at rs12785878 (DHCR7), rs10741657 (CYP2R1), rs6013897 (CYP24A1), and rs2282679 (GC) were genotyped. Interventions: 1000 IU/d cholecalciferol from 14 weeks of gestation until delivery. Main Outcome Measure: 25(OH)D at randomization and 34 weeks of gestation were measured in a single batch (Liaison; Diasorin, Dartford, UK). Associations between 25(OH)D and the SNPs were assessed by linear regression using an additive model [ß represents the change in 25(OH)D per additional common allele]. Results: Only rs12785878 (DHCR7) was associated with baseline 25(OH)D [ß = 3.1 nmol/L; 95% confidence interval (CI), 1.0 to 5.2 nmol/L; P < 0.004]. In contrast, rs10741657 (CYP2R1) (ß = -5.2 nmol/L; 95% CI, -8.2 to -2.2 nmol/L; P = 0.001) and rs2282679 (GC) (ß = 4.2 nmol/L; 95% CI, 0.9 to 7.5 nmol/L; P = 0.01) were associated with achieved 25(OH)D status following supplementation, whereas rs12785878 and rs6013897 (CYP24A1) were not. Conclusions: Genetic variation in DHCR7, which encodes 7-dehyrocholesterol reductase in the epidermal vitamin D biosynthesis pathway, appears to modify baseline 25(OH)D. In contrast, the response to antenatal cholecalciferol supplementation was associated with SNPs in CYP2R1, which may alter 25-hydroxylase activity, and GC, which may affect vitamin D binding protein synthesis or metabolite affinity.


Assuntos
Colecalciferol/uso terapêutico , Deficiência de Vitamina D/prevenção & controle , Vitaminas/uso terapêutico , Adulto , Alelos , Colestanotriol 26-Mono-Oxigenase/genética , Família 2 do Citocromo P450/genética , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Genótipo , Humanos , Modelos Lineares , Análise Multivariada , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Polimorfismo de Nucleotídeo Único , Gravidez , Resultado do Tratamento , Vitamina D/análogos & derivados , Vitamina D/sangue , Proteína de Ligação a Vitamina D/genética , Vitamina D3 24-Hidroxilase/genética , Adulto Jovem
7.
J Clin Endocrinol Metab ; 101(12): 5012-5020, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27788053

RESUMO

CONTEXT: Current approaches to antenatal vitamin D supplementation do not account for interindividual differences in 25-hydroxyvitamin D (25(OH)D) response. OBJECTIVE: We assessed which maternal and environmental characteristics were associated with 25(OH)D after supplementation with cholecalciferol. DESIGN: Within-randomization-group analysis of participants in the Maternal Vitamin D Osteoporosis Study trial of vitamin D supplementation in pregnancy. SETTING: Hospital antenatal clinics. PARTICIPANTS: A total of 829 pregnant women (422 placebo, 407 cholecalciferol). At 14 and 34 weeks of gestation, maternal anthropometry, health, and lifestyle were assessed and 25(OH)D measured. Compliance was determined using pill counts at 19 and 34 weeks. INTERVENTIONS: 1000 IU/d of cholecalciferol or matched placebo from 14 weeks of gestation until delivery. MAIN OUTCOME MEASURE: 25(OH)D at 34 weeks, measured in a single batch (Diasorin Liaison). RESULTS: 25(OH)D at 34 weeks of gestation was higher in the women randomized to vitamin D (mean [SD], 67.7 [21.3] nmol/L) compared with placebo (43.1 [22.5] nmol/L; P < .001). In women randomized to cholecalciferol, higher pregnancy weight gain from 14 to 34 weeks of gestation (kg) (ß = -0.81 [95% confidence interval -1.39, -0.22]), lower compliance with study medication (%) (ß = -0.28 [-0.072, -0.48]), lower early pregnancy 25(OH)D (nmol/L) (ß = 0.28 [0.16, 0.40]), and delivery in the winter vs the summer (ß = -10.5 [-6.4, -14.6]) were independently associated with lower 25(OH)D at 34 weeks of gestation. CONCLUSIONS: Women who gained more weight during pregnancy had lower 25(OH)D in early pregnancy and delivered in winter achieved a lower 25(OH)D in late pregnancy when supplemented with 1000 IU/d cholecalciferol. Future studies should aim to determine appropriate doses to enable consistent repletion of 25(OH)D during pregnancy.


Assuntos
Colecalciferol/farmacologia , Avaliação de Resultados em Cuidados de Saúde , Gravidez/sangue , Vitamina D/análogos & derivados , Vitaminas/farmacologia , Aumento de Peso , Adulto , Colecalciferol/administração & dosagem , Método Duplo-Cego , Feminino , Humanos , Gravidez/efeitos dos fármacos , Trimestres da Gravidez , Estações do Ano , Vitamina D/sangue , Vitaminas/administração & dosagem , Adulto Jovem
8.
Lancet Diabetes Endocrinol ; 4(5): 393-402, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26944421

RESUMO

BACKGROUND: Maternal vitamin D status has been associated with bone mass of offspring in many, but not all, observational studies. However, maternal vitamin D repletion during pregnancy has not yet been proven to improve offspring bone mass in a randomised controlled trial. We aimed to assess whether neonates born to mothers supplemented with vitamin D during pregnancy have greater whole-body bone mineral content (BMC) at birth than those of mothers who had not received supplementation. METHODS: The Maternal Vitamin D Osteoporosis Study (MAVIDOS) was a multicentre, double-blind, randomised, placebo-controlled trial that recruited pregnant women from three study sites in the UK (Southampton, Oxford, and Sheffield). Eligible participants were older than 18 years, with a singleton pregnancy, gestation of less than 17 weeks, and a serum 25-hydroxyvitamin D (25[OH]D) concentration of 25-100 nmol/L at 10-17 weeks' gestation. P'articipants were randomly assigned (1:1), in randomly permuted blocks of ten, to either cholecalciferol 1000 IU/day or matched placebo, taken orally, from 14 weeks' gestation (or as soon as possible before 17 weeks' gestation if recruited later) until delivery. Participants and the research team were masked to treatment allocation. The primary outcome was neonatal whole-body BMC, assessed within 2 weeks of birth by dual-energy x-ray absorptiometry (DXA), analysed in all randomly assigned neonates who had a usable DXA scan. Safety outcomes were assessed in all randomly assigned participants. This trial is registered with the International Standard Randomised Controlled Trial registry, ISRCTN 82927713, and the European Clinical Trials Database, EudraCT 2007-001716-23. FINDINGS: Between Oct 10, 2008, and Feb 11, 2014, we randomly assigned 569 pregnant women to placebo and 565 to cholecalciferol 1000 IU/day. 370 (65%) neonates in the placebo group and 367 (65%) neonates in the cholecalciferol group had a usable DXA scan and were analysed for the primary endpoint. Neonatal whole-body BMC of infants born to mothers assigned to cholecalciferol 1000 IU/day did not significantly differ from that of infants born to mothers assigned to placebo (61·6 g [95% CI 60·3-62·8] vs 60·5 g [59·3-61·7], respectively; p=0·21). We noted no significant differences in safety outcomes, apart from a greater proportion of women in the placebo group with severe post-partum haemorrhage than those in the cholecalciferol group (96 [17%] of 569 mothers in the placebo group vs 65 [12%] of 565 mothers in the cholecalciferol group; p=0·01). No adverse events were deemed to be treatment related. INTERPRETATION: Supplementation of women with cholecalciferol 1000 IU/day during pregnancy did not lead to increased offspring whole-body BMC compared with placebo, but did show that 1000 IU of cholecalciferol daily is sufficient to ensure that most pregnant women are vitamin D replete, and it is safe. These findings support current approaches to vitamin D supplementation in pregnancy. Results of the ongoing MAVIDOS childhood follow-up study are awaited. FUNDING: Arthritis Research UK, Medical Research Council, Bupa Foundation, and National Institute for Health Research.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Densidade Óssea/efeitos dos fármacos , Recém-Nascido , Fenômenos Fisiológicos da Nutrição Pré-Natal , Vitamina D/administração & dosagem , Adulto , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Gravidez , Estações do Ano
9.
Trials ; 13: 13, 2012 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-22314083

RESUMO

UNLABELLED: MAVIDOS is a randomised, double-blind, placebo-controlled trial (ISRCTN82927713, registered 2008 Apr 11), funded by Arthritis Research UK, MRC, Bupa Foundation and NIHR. BACKGROUND: Osteoporosis is a major public health problem as a result of associated fragility fractures. Skeletal strength increases from birth to a peak in early adulthood. This peak predicts osteoporosis risk in later life. Vitamin D insufficiency in pregnancy is common (31% in a recent Southampton cohort) and predicts reduced bone mass in the offspring. In this study we aim to test whether offspring of mothers supplemented with vitamin D in pregnancy have higher bone mass at birth than those whose mothers were not supplemented. METHODS/DESIGN: Women have their vitamin D status assessed after ultrasound scanning in the twelfth week of pregnancy at 3 trial centres (Southampton, Sheffield, Oxford). Women with circulating 25(OH)-vitamin D levels 25-100 nmol/l are randomised in a double-blind design to either oral vitamin D supplement (1000 IU cholecalciferol/day, n = 477) or placebo at 14 weeks (n = 477). Questionnaire data include parity, sunlight exposure, dietary information, and cigarette and alcohol consumption. At 19 and 34 weeks maternal anthropometry is assessed and blood samples taken to measure 25(OH)-vitamin D, PTH and biochemistry. At delivery venous umbilical cord blood is collected, together with umbilical cord and placental tissue. The babies undergo DXA assessment of bone mass within the first 14 days after birth, with the primary outcome being whole body bone mineral content adjusted for gestational age and age. Children are then followed up with yearly assessment of health, diet, physical activity and anthropometric measures, with repeat assessment of bone mass by DXA at age 4 years. DISCUSSION: As far as we are aware, this randomised trial is one of the first ever tests of the early life origins hypothesis in human participants and has the potential to inform public health policy regarding vitamin D supplementation in pregnancy. It will also provide a valuable resource in which to study the influence of maternal vitamin D status on other childhood outcomes such as glucose tolerance, blood pressure, cardiovascular function, IQ and immunology.


Assuntos
Densidade Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Colecalciferol/administração & dosagem , Suplementos Nutricionais , Osteoporose/prevenção & controle , Complicações na Gravidez/prevenção & controle , Projetos de Pesquisa , Deficiência de Vitamina D/prevenção & controle , Absorciometria de Fóton , Administração Oral , Fatores Etários , Biomarcadores/sangue , Osso e Ossos/diagnóstico por imagem , Pré-Escolar , Método Duplo-Cego , Inglaterra , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Osteoporose/etiologia , Osteoporose/metabolismo , Gravidez , Resultado do Tratamento , Vitamina D/análogos & derivados , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/complicações
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