Prenatal Vitamin D Supplementation and Child Respiratory Health: A Randomised Controlled Trial

Abstract

BackgroundObservational studies suggest high prenatal vitamin D intake may be associated with reduced childhood wheezing. We examined the effect of prenatal vitamin D on childhood wheezing in an interventional study.MethodsWe randomised 180 pregnant women at 27 weeks gestation to either no vitamin D, 800 IU ergocalciferol daily until delivery or single oral bolus of 200,000 IU cholecalciferol, in an ethnically stratified, randomised controlled trial. Supplementation improved but did not optimise vitamin D status. Researchers blind to allocation assessed offspring at 3 years. Primary outcome was any history of wheeze assessed by validated questionnaire. Secondary outcomes included atopy, respiratory infection, impulse oscillometry and exhaled nitric oxide. Primary analyses used logistic and linear regression.ResultsWe evaluated 158 of 180 (88%) offspring at age 3 years for the primary outcome. Atopy was assessed by skin test for 95 children (53%), serum IgE for 86 (48%), exhaled nitric oxide for 62 (34%) and impulse oscillometry of acceptable quality for 51 (28%). We found no difference between supplemented and control groups in risk of wheeze [no vitamin D: 14/50 (28%); any vitamin D: 26/108 (24%) (risk ratio 0.86; 95% confidence interval 0.49, 1.50; P = 0.69)]. There was no significant difference in atopy, eczema risk, lung function or exhaled nitric oxide between supplemented groups and controls.ConclusionPrenatal vitamin D supplementation in late pregnancy that had a modest effect on cord blood vitamin D level, was not associated with decreased wheezing in offspring at age three years.Trial RegistrationControlled-Trials.com ISRCTN68645785

Does maternal diet during pregnancy and lactation affect outcomes in offspring? A systematic review of food-based approaches

“…One RCT evaluating the effect of vitamin D supplementation in 180 women during late pregnancy reported no difference between offspring in the supplemented or unsupplemented groups for wheeze, allergic disease, lung function or allergic inflammation in the first three years [88]. The outcomes of other vitamin D supplementation intervention trials that are in progress will provide information for future evidence-based dietary guidelines related to vitamin D in the diet and development of atopy.…”

Early-life origins of chronic respiratory diseases: understanding and promoting healthy ageing

“…Studies on folic acid intake during pregnancy and asthma in children have also generally found no association between the two [82][83][84][85]. According to several large birth cohort studies, vitamin D intake or plasma levels during pregnancy are generally not associated with childhood asthma or lung function [86][87][88][89], and an RCT examining the effects of vitamin D supplementation during pregnancy (n5180) found no significant difference in children's wheezing at 3 years of age [90].…”

Prenatal Intake of Vitamins and Allergic Outcomes in the Offspring: A Systematic Review and Meta-Analysis

“…These included trials (including total of 2456 children) were represented by 217 five original papers [13][14][15][16][17] and four grouped as their companion papers [18][19][20][21] . 218 Table 1 shows the characteristics of the included trials, their companion 219 papers and study population.…”

“…The types of vitamin supplementations included 221 were as vitamins C+E 13 , vitamin D 14,[16][17] and crushed vitamin C 15 . The 222 duration of intervention and follow-up in the included studies varied from 3.5-4 223 to 7.5 months and 12 to 36 months respectively.…”

“…The studies were of unselected pregnant 377 women 16 , women with a history of atopy 17 , pregnant women at risk of 378 developing pre-eclampsia 13 , different ethnic/race groups 14 and smoking 379 pregnant women 15 . Two studies were judged to have a high risk of bias due to 380 their performance bias [13][14] or high rate of loss to follow-up 13 . All trials were 381 rated having low risk of bias for blinding of outcome assessment.…”