Brain Aging and Treatment Response in Geriatric Depression

Inclusion Criteria: * Meets the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria for major depressive disorder (recurrent and nonrecurrent course will be identified) * Score of 16 or higher on the 24-item Hamilton Rating Scale for Depression (HDRS) at study entry * Score of 24 or higher on the Mini-Mental State Exam (MMSE) * Age 60 years old or older Exclusion Criteria: * History of psychiatric illness or a substance abuse disorder other than unipolar depression, diagnosed prior to the onset of the first depressive episode * Presence of psychotic symptoms * Severe or acute medical illness (e.g., major surgery, metastatic cancer, stroke, heart attack) 6 months prior to study entry * Acute suicidal or violent behavior or history of suicide attempt within the year prior to study entry * Presence of delirium, neurodegenerative dementia, Parkinson's disease, or any other central nervous system (CNS) diseases * Toxic or metabolic abnormalities on laboratory examination * Medications taken or medical illnesses present that could account for depression * Active heart failure categorized as Class III or greater according to New York Heart Association criteria * Heart attack or crescendo angina within the 3 months prior to study entry * Symptomatic cardiac arrhythmias or symptomatic, hemodynamically significant mitral or aortic valvular disease * Resting heart rate less than 50 beats per minute and a corrected QT (QTc) interval greater than 0.45 seconds * Secon…