Predictors of depressive symptoms in patients with COPD and health impact

While depression is a common co-morbid condition among patients with COPD, little is known about predictors or health impact of depression among these patients. To address these gaps in knowledge we conducted a cross-sectional survey of 207 patients with COPD cared for in a network of primary care clinics affiliated with an urban academic health center. A standardized questionnaire was used to measure demographic characteristics, smoking status, co-morbid medical conditions, current medications, self-efficacy, social support, illness intrusiveness, and self-reported health care utilization during the previous 6 months. Depressive symptoms were assessed using the Centers for Epidemiologic Studies-Depression scale. Overall, the prevalence of moderate to high levels of depressive symptoms was 60.4%. In a multivariate analysis independent predictors of depressive symptoms were being a former smoker (OR = 0.41 (95% CI 0.19-0.89)), higher self-efficacy (OR = 0.42 (0.28-0.64)), higher social support (OR = 0.72 (0.52-0.99)), and higher perceived illness intrusiveness (OR = 1.05 (1.02-1.08)). Depressive symptoms were associated with increased physician visits, emergency room visits, and hospitalizations for lung disease. In conclusion, depressive symptoms are common among patients with COPD and associated with an increase in healthcare utilization. These findings suggest that the identification of risk factors for depressive symptoms (e.g., continued smoking) may increase detection and improve management of depression and health outcomes among patients with COPD.