Rationale: We have previously reported an association between reduced maternal vitamin E intake during pregnancy and wheezing in 2-yr-old children.
Objectives: To assess whether maternal nutrient intake during pregnancy is associated with asthma-related outcomes in children aged 5 yr.
Methods: A longitudinal cohort study of 1,861 children born to women recruited during pregnancy and followed up at 5 yr.
Measurements: Maternal nutrient status was assessed by a food frequency questionnaire and plasma levels. Respiratory and food frequency questionnaires were completed at 5 yr and children were invited for measurement of spirometry and skin-prick testing.
Main results: Symptom and food frequency questionnaire data were available for 1,253 and 1,120 children, respectively; 700 children were skin prick tested, and FEV(1) was measured in 478 and exhaled nitric oxide in 167 children. In 5-yr-old children, maternal vitamin E intake during pregnancy was negatively associated with wheeze in previous year (odds ratio per intake quintile, 0.82; 95% confidence interval, 0.71-0.95), asthma ever (0.84, 0.72-0.98), asthma and wheeze in previous year (0.79, 0.65-0.95), and persistent wheezing (0.77, 0.63-0.93). Maternal plasma alpha-tocopherol during pregnancy was positively associated with post-bronchodilator FEV(1) at 5 yr, with a 7-ml (95% confidence interval, 0-14; p = 0.04) increase in FEV(1) per microg/ml alpha-tocopherol. Maternal zinc intake during pregnancy was negatively associated with asthma ever (0.83, 0.71-0.78) and active asthma (0.72, 0.59-0.89). There were no associations between children's nutrient intake and respiratory outcomes.
Conclusion: Maternal intake of foods containing vitamin E and zinc during pregnancy is associated with differences in the risks of developing childhood wheeze and asthma.