Medical comorbidity and late life depression: what is known and what are the unmet needs?

Depression is an important problem in older patients with multiple medical problems, where the under-recognition and undertreatment of depression is especially common. A large number of studies assessing the relationship between depression and medical burden have focused on patients with cardiac disease, and recent research has focused on the role of depression as an independent risk factor for cardiac disease, mortality, and functional status in elderly patients. In particular, among coronary bypass surgery patients, depressive symptoms were found to occur most commonly in those with the highest comorbidity. In the treatment of depression in older adults, both pharmacologic and psychosocial interventions have shown promise, but such treatments need to be tested to determine whether mortality and functional status are affected. From a methodological perspective, new studies will need to control for comorbid disease, as many previous studies suggesting depression as a risk factor for mortality in cardiovascular patients have not consistently done so.