Background: Although depression is a risk factor for adverse outcomes in chronic illness, little is known about the prevalence or risk factors for depressive symptoms in chronic obstructive pulmonary disease (COPD).
Objective: To determine the prevalence of depressive symptoms in COPD as compared to other chronic illnesses and to identify risk factors for depressive symptoms in COPD.
Design and patients: Cross-sectional study of 18,588 persons (1,736 subjects with self-reported COPD), representing a sample of the US population aged > or =50 years who participated in the 2004 Health and Retirement Survey.
Measurements: Presence of COPD and other chronic conditions was defined by self-report. Presence of depressive symptoms was assessed using the CES-D8 scale. Participants with a score > or =3 on CES-D8 were classified as having clinically significant depressive symptoms.
Main results: Of 1,736 participants with COPD, 40% had > or =3 depressive symptoms. Depressive symptoms were more common in COPD than in coronary heart disease, stroke, diabetes, arthritis, hypertension, and cancer. Risk factors for > or =3 depressive symptoms in COPD: younger age (OR 1.02/per year younger, 95% CI [1.02-1.03]), female gender (1.2 [1.1-1.3]), current smoking (1.5 [1.3-1.7]), marital status [divorced/separated (1.8 [1.6-2.1]), widowed (1.8 [1.6-2]), never married (1.4 [1.1-1.8]), < or =high school degree (1.6 [1.5-1.8]), dyspnea (2.3 [2.1-2.6]), difficulty walking (2.8 [2.5-3.2]), and co-morbid diabetes (1.2 [1.1-1.4]), arthritis (1.3 [1.2-1.5]) or cancer (1.2 [1.1-1.4]).
Conclusions: Depressive symptoms are common in COPD and are more likely to occur in COPD than in other common chronic illnesses. The risk factors identified may be used for targeted depression screening in COPD patients.