Children whose mothers consumed the highest levels of vitamin E during pregnancy had less asthma and wheezing than did their peers whose mothers consumed less vitamin E while pregnant, according to findings from a cohort study.
Dr. Graham Devereux and colleagues from the University of Aberdeen (Scotland) found that 5-year-old children of women with the highest intake of vitamin E during pregnancy had the lowest incidence of wheezing, physician visits because of wheezing, and both suspected and physician-diagnosed asthma (Am. J. Respir. Crit. Care Med. 2006;174:499–507).
A group of 2,000 expectant mothers was initially recruited in 1997 and 1999 from prenatal clinics, at a median of 12 weeks' gestation. A total of 1,856 women completed a questionnaire, underwent a skin-prick test to assess atopic status, and provided a blood sample. At 32 weeks' gestation, 1,704 women answered a food-frequency questionnaire (FFQ) to assess dietary intake during the preceding 3 months. Upon delivery, maternal and infant (cord blood) plasma was sampled in 1,134 mothers and 877 infants and analyzed for antioxidant content via liquid chromatography.
Six weeks after their singleton children turned 5 years old, a questionnaire was mailed to each child's family to assess history of wheezing and asthma; 1,253 were completed and received. A total of 1,120 parents who responded to this questionnaire filled out an additional FFQ based on the child's diet, and parents of 797 children accepted an invitation to take the child to the hospital for spirometry, skin-prick testing, and fraction of exhaled nitric oxide measurement.
Ultimately, “children born to mothers with the lowest quintile of vitamin E intake [were] 3.47 times more likely to be of the persistent wheezing phenotype than [were] children born to mothers with the highest quintile of vitamin E intake,” the investigators wrote.
They had reported an association between maternal vitamin E intake during pregnancy and asthma at age 2 years in the same cohort.