Short‐and Long‐term Efficacy of Electroconvulsive Therapy for Late‐life Depression: A Pilot Study

Abstract

Background: Electroconvulsive therapy (ECT) is often administered among the elderly, who are particularly likely to have concurrent medical conditions and medication intolerance. Objective: To examine the short‐and long‐term efficacy of ECT for late‐life depression, we performed a two‐phase, prospective, naturalistic follow‐up study that compared treatment outcome in old‐aged with that in middle‐aged subjects. Methods: Phase I study: Twenty‐one subjects who were consecutively referred for ECT, aged at least 50 years, and met the DSM‐IV criteria for a major depressive episode were enrolled. Before ECT, severity of concurrent medical conditions was assessed with the cumulative illness rating scale (CIRS). Before and after a course of ECT, the severity of depressive symptoms was evaluated with the 17‐item Hamilton rating scale for depression (HAM‐D). Phase II study: Seventeen subjects who responded to an acute ECT course in the phase I study were enrolled. Various continuation medications were administered, and symptoms were monitored and evaluated with the HAM‐D for 24 weeks or until relapse. Results: Overall the subjects had an 81 % short‐term response rate and a 47% relapse rate within 24 weeks after ECT. Response and relapse rates were not significantly different between the middle‐and old‐aged groups (response rates: 91% vs. 70%; relapse rates: 40% vs. 57%). However, the old‐aged patients had higher post‐ECT HAM‐D scores than the middle‐aged patients did (P<0.05), and CIRS scores positively correlated with post‐ECT HAM‐D scores (P<0.05). Relapsers tended to have higher CIRS scores than non‐relapsers did (P=0.06). Conclusion: In late‐life depression, the short‐term response rate to ECT is considerably good, but the relapse rate was relatively high. Clinicians need to take into consideration the age of patient and any concurrent medical conditions, when planning long‐term management of residual depressive symptoms and prevention of relapse after an initial good response to ECT.