Late-life depression: when and how to intervene.

Late-life depression ranges from mild to severe and can lead to significant physical and social limitations. Up to one-third of patients with medical disorders also suffer from depressive symptoms. Differential diagnosis of depression is often confounded by medical conditions that impair cognitive functioning, such as Alzheimer's disease and vascular dementia. Depression is a modifiable risk factor for suicide in old age. Once diagnosed, depression is a highly treatable disease. Treatment modalities include psychotherapy, antidepressants, and electroconvulsive therapy for intractable cases. Many patients are now being treated in primary care settings, due to managed care limits on referrals and to patient reluctance to seek psychiatric care.