Familial depression and respiratory illness in children

Objective: To determine the relationship between parental major depression and respiratory illness in youth. Design: Three-generation family cohort study. Setting: Baseline study initiated at the Yale University Depression Research Unit. Participants: One hundred sixty-one children and their parents and grandparents. Main Exposure: Family history of major depression. Main Outcome Measures: We studied the lifetime prevalence of respiratory illness and a range of other physical disorders, including gastrointestinal, neurodevelopmental, and cardiovascular diseases, in offspring of parents with and without major depression. Analyses were also stratified by parental and grandparental major depression status and were adjusted for age, sex, parental prenatal smoking, and parental functional impairment. Results: Parental major depression is associated with a significantly increased likelihood of respiratory illness in youth (odds ratio, 3.7; 95% confidence interval, 1.6-8.6). This association persists after adjusting for age, sex, parental prenatal smoking, parental respiratory disease, and parental functional impairment. Conclusions: Our results suggest that youth of parents with major depression may have heightened vulnerability to respiratory illness. Neither parental respiratory illness, prenatal smoking, nor functional impairment appears to explain this link.