The Longitudinal Occurrence and Impact of Comorbid Chronic Pain and Chronic Depression over Two Years in Continuing Care Retirement Community Residents

OBJECTIVE: To describe the longitudinal course of depressive symptoms and pain experienced by continuing care retirement community (CCRC) residents and to investigate the impact of comorbid chronic activity-limiting pain and chronic high depressive symptoms on physical functioning and health service use. METHODS: This longitudinal study of 169 CCRC residents involved five assessments (baseline and four in-person interviews at 6-month intervals). The Geriatric Depression Scale (GDS), questions drawn from the McGill Pain Questionnaire, and self-report data on physical functioning and health care use were assessed. Individuals reporting activity-limiting pain and those with GDS scores > or =11 at three or more assessments were considered to have chronic pain or chronic depression, respectively. The analysis sample included 169 CCRC residents. Multivariate logistic regression was used to test hypotheses. RESULTS: Pain and depressive symptoms were characterized by longitudinal stability. Of the sample, 37% met the criteria for chronic activity-limiting pain, 21% met the criteria for chronic high depressive symptoms, and 13% were comorbid. Adjusting for age and health conditions, those with chronic activity-limiting pain were five times more likely than those in the lowest pain group to persistently be in the worst two quartiles of physical functioning, as were those with even one GDS score >5. The odds of poor physical functioning were 11.2 times greater in those with comorbid chronic pain and depression. Comparable greater odds were seen in this sample for frequency of medical care visits (adjusted odds ratio AOR]=12.4) and consistently high use of all medical services (AOR=3.5). CONCLUSIONS: Pain and depressive symptoms were both common and appeared remarkably stable over time. Depressive symptoms contributed significantly to the prediction of impairment associated with pain, and identification and treatment of such symptoms, even minor symptoms, could reduce pain-related impairment and health care costs in the elderly.