Maternal dietary flavonoid intake and child wheeze and asthma in the Conditions Affecting Neurocognitive Development and Learning in Early Childhood (CANDLE) cohort

Background: Higher intakes of flavonoids have been associated with better lung function in adults. The aim of this study was to examine the associations between maternal prenatal intake of flavonoids and offspring asthma and wheeze. Methods: We conducted a prospective study of Black (62.8%) and White (37.2%) mother–child dyads (N = 906) enrolled in the CANDLE study. We estimated prenatal dietary flavonoid intake using the Block Food Frequency Questionnaire administered during the second trimester and subsequently linked to the United States Department of Agriculture's Provisional Flavonoid Addendum and Proanthocyanidin database. Our primary outcomes included parent report of child current wheeze and asthma (based on diagnosis, symptoms, and/or medication use) at approximately age 4 years. We used multivariable logistic regression to investigate associations between prenatal flavonoid intake and child respiratory outcomes. Results: Overall, 19.4% and 15.8% of children had current wheeze and asthma, respectively. The highest quartile of prenatal dietary total flavonoid was associated with lower odds of childhood respiratory outcomes, relative to the lowest quartile, for current wheeze (adjusted odds ratios (aOR) [95% confidence intervals (CI)]: 0.58 [0.35, 0.96]) and current asthma (aOR [95% CI]: 0.53 [0.31, 0.91]), respectively, although there was not a clear dose–response. We observed an inverse association between the prenatal intake of proanthocyanidin and offspring current asthma, but no associations for other flavonoid subclasses. Conclusions: We report a novel finding that children of women with the highest compared to the lowest prenatal intake of total dietary flavonoids had lower odds of current wheeze and asthma at age 4 years.