Asthma and depression: the Cooper Center Longitudinal Study.

BACKGROUND: Prior research suggests a possible association between asthma and depression. OBJECTIVE: To examine the association between asthma and depressive symptoms, controlling for asthma medications, lung function, and overall health. METHODS: We conducted a cross-sectional study of 12,944 adults who completed physician-based preventive health examinations at the Cooper Clinic from 2000 to 2012. Information on medical histories, including asthma and depression, and medications were collected. Participants reported overall health status, completed spirometry testing, and underwent depression screening using the 10-item Center for Epidemiologic Studies Depression Scale (CES-D). Dependent variables of current depressive symptoms (CES-D scores ≥10) and lifetime history of depression were separately modeled using logistic regression with independent variables, including demographics, spirometry, asthma controller medications, and patient-reported health status. RESULTS: The sample was predominantly white and well educated. The prevalence of asthma was 9.0%. Asthma was associated with an odds ratio (OR) of 1.41 (95% CI, 1.16-1.70; P < .001) of current depressive symptoms based on CES-D score. Asthma was also associated with lifetime history of depression (OR, 1.66; 95% CI, 1.40-1.95; P < .001). Neither lung function nor asthma controller medications were significantly associated with depression. CONCLUSION: Asthma was associated with increased prevalence of current depressive symptoms and lifetime depression in a large sample of relatively healthy adults. These findings suggest that the increased likelihood of depression among patients with asthma does not appear to be exclusively related to severe or poorly controlled asthma. People with asthma, regardless of severity, may benefit from depression screening in clinical settings.