Maternal vitamin D intake during pregnancy and early childhood wheezing.
BACKGROUND
Maternal intake of vitamin D in pregnancy is a potentially modifiable but understudied risk factor for the development of asthma in children.


OBJECTIVE
We investigated whether maternal vitamin D intake in pregnancy is associated with decreased risks of wheezing symptoms in young children.


METHODS
Subjects were from a birth cohort recruited in utero with the primary objective of identifying associations between maternal diet during pregnancy and asthma and allergies in children. A random sample of 2000 healthy pregnant women was recruited while attending antenatal clinics at the Aberdeen Maternity Hospital, Scotland, at approximately 12 wk gestation. Maternal vitamin D intake was ascertained from a food-frequency questionnaire completed at 32 wk of gestation. The main outcome measures were wheezing symptoms, spirometry, bronchodilator response, atopic sensitization, and exhaled nitric oxide at 5 y.


RESULTS
Respiratory details through 5 y and maternal food-frequency-questionnaire data were available for 1212 children. In models adjusted for potential confounders, including the children's vitamin D intake, a comparison of the highest and lowest quintiles of maternal total vitamin D intake conferred lower risks for ever wheeze [odds ratio (OR): 0.48; 95% CI: 0.25, 0.91], wheeze in the previous year (OR: 0.35; 95% CI: 0.15, 0.83), and persistent wheeze (OR: 0.33; 95% CI: 0.11, 0.98) in 5-y-old children. In addition, lower maternal total vitamin D intakes in pregnancy were also associated with decreased bronchodilator response (P = 0.04). No associations were observed between maternal vitamin D intakes and spirometry or exhaled nitric oxide concentrations.


CONCLUSIONS
Increasing maternal vitamin D intakes during pregnancy may decrease the risk of wheeze symptoms in early childhood.
Devereux
Graham
G
Department of Environmental, University of Aberdeen, Aberdeen, United Kingdom.
Litonjua
Augusto A
AA
Turner
Stephen W
SW
Craig
Leone C A
LC
McNeill
Geraldine
G
Martindale
Sheelagh
S
Helms
Peter J
PJ
Seaton
Anthony
A
Weiss
Scott T
ST
D002675:Child, Preschool; D004032:Diet; D005260:Female; D006801:Humans; D011247:Pregnancy / Q000502:physiology*; D012135:Respiratory Sounds / Q000503:physiopathology*; D013147:Spirometry; D011795:Surveys and Questionnaires; D014807:Vitamin D / Q000378:metabolism*
D014807:Vitamin D