Predictors of Remission After Electroconvulsive Therapy in Unipolar Major Depression

Alexandre Y. Dombrovski, M.D.; Benoit H. Mulsant, M.D.; Roger F. Haskett, M.D.; Joan Prudic, M.D.; Amy E. Begley, M.A.; and Harold A. Sackeim, Ph.D.

Context: Electroconvulsive therapy (ECT) is the most effective biological treatment for major depression. However, there is little agreement about clinically useful predictors of acute ECT outcomes.

Objective: To assess whether age, sex, burden of comorbid physical illness, age at onset, history of recurrence, episode duration, chronic depression or comorbid dysthymia, melancholic features, episode severity, and medication resistance are predictors of remission after an acute course of ECT.

Design: We performed an analysis using data gathered prospectively in 328 patients with unipolar major depression (according to Research Diagnostic Criteria) treated with ECT. The study was conducted from 1993 through 1999. Patients had a pretreatment score of 21 or higher on the 24-item Hamilton Rating Scale for Depression (HAM-D). Treatment history was assessed using the Antidepressant Treatment History Form. Remission was defined as a 24-item HAM-D score of 10 or less and a 60% or more relative reduction of the HAM-D score.

Results: On univariate logistic regression, statistically significant predictors of nonremission were chronic depression/dysthymia, medication resistance, longer episode duration, and younger age. On backward elimination logistic regression, only medication resistance (OR = 1.67, 95% CI = 1.05 to 2.67) and chronic depression/dysthymia (OR = 1.84, 95% CI = 1.06 to 3.21) were statistically significant predictors of nonremission.

Conclusions: In patients with major depression, lower rates of remission after acute ECT are associated with medication resistance and chronicity, but not with age or burden of physical illness.

(J Clin Psychiatry 2005;66:1043-1049)

Received Oct. 11, 2004; accepted Jan. 18, 2005. From the Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine (Drs. Dombrovski, Mulsant, and Haskett and Ms. Begley); the Geriatric Research, Education, and Clinical Center (GRECC), VA Pittsburgh Health System (Dr. Mulsant), Pittsburgh, Pa.; and the New York State Psychiatric Institute and Columbia University College of Physicians and Surgeons, New York

(Drs. Prudic and Sackeim).

Supported in part by U.S. Public Health Service grants MH30915, MH48512, MH52247, and MH01613 from the National Institute of Mental Health. MECTA Corporation donated equipment to the investigators.

Financial disclosure appears at the end of the article.

Corresponding author and reprints: Benoit H. Mulsant, M.D., WPIC (E837), 3811 O'Hara Street, Pittsburgh, PA 15213 (e-mail: mulsantbh@upmc.edu).