Objective: Since co-morbid depression can complicate medical conditions such as cardiovascular disease and cancer, physicians may treat depression more aggressively in patients with these conditions. This study compared antidepressant medication use in persons with and without medical co-morbidities.
Methods: This cross-sectional study was conducted in a national network of outpatient electronic medical record users. Participants included active adult patients with an active diagnosis of depression as of 11/30/05 (the "prevalent" population, 185,029 patients) or a new episode of depression during the one-year period 12/1/03-11/30/04 (the "incident" population, 29,768 patients). For each population, four co-morbid conditions were defined--diabetes, coronary heart disease (CHD), stroke, and cancer. Prescription of antidepressant medication was compared for persons with and without each medical condition.
Results: The most common medical condition was diabetes, with cancer being the least common (7.6% and 2.4% of the prevalent population). Overall, 69.6% of the prevalent population and 76.1% of the incident population were treated with antidepressant medications. For the prevalent population, treatment was significantly more likely for patients with diabetes (OR 1.07, 95% CI 1.03-1.11) but significantly less likely for patients with CHD (OR 0.94 95% CI 0.90-0.99), after controlling for differences in age and gender. For the incident population, treatment was significantly more likely for persons with diabetes (OR 1.14, 95% CI 1.04-1.26), CHD (OR 1.23 95% CI 1.08-1.39), and stroke (OR 1.21, 95% CI 1.04-1.42).
Conclusions: Antidepressant medication use was somewhat higher in persons with medical co-morbidities, although these differences were small and inconsistent.