Depressive symptoms and the incidence of adult-onset asthma in African American women

Background: Some evidence suggests that depression may increase the risk of adult-onset asthma. No data are available for African American women, in whom the prevalence of depression and asthma is high. Objective: To conduct prospective analyses of the relation of depressive symptoms to asthma incidence in the Black Women's Health Study, a prospective cohort of US black women followed since 1995 with mailed biennial questionnaires. Methods: Of 31,848 participants followed from 1999 to 2011, 771 reported incident asthma. Depressive symptoms were ascertained on 1999 and 2005 follow-up questionnaires with the Center for Epidemiological Studies-Depression Scale (CES-D). Participants rated the frequency of 20 symptoms. A score was calculated by summing the responses to all questions. Cox regression models were used to derive incidence rate ratios and 95% confidence intervals for 4 categories of the CES-D score in relation to incident asthma, adjusted for body mass index, smoking, and other covariates. Results: The multivariable incidence rate ratio in the highest category of CES-D score (>= 33) compared with the lowest (< 16) was 2.08 (95% confidence interval 1.58-2.74), with a significant trend (P < .0001). The incidence rate ratio was higher in women who took antidepressants, were current or former smokers, were not obese, and were at least 40 years old, although there were no statistically significant interactions. Conclusion: A positive association was observed between CES-D score and the incidence of adult-onset asthma. If the hypothesis is confirmed, depression could contribute substantially to the burden of asthma in adults. (C) 2014 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.