To define the role of continuation electroconvulsive therapy (C-ECT) in relapse-prevention of seriously ill patients with major depressive disorder (MDD). To determine the relative efficacy and safety of C-ECT in comparison to the traditional approach of continuation pharmacotherapy (C-PHARM) to prevent relapses of MDD.

Electroconvulsive therapy (ECT) is a highly effective treatment for MDD that is helpful for patients with the most severe forms of affective illness; however, relapse after successful acute phase ECT or pharmacotherapy remains a major public health problem. To prevent relapse in patients with MDD who have responded to ECT, the common practice is to prescribe an antidepressant (e.g., a tricyclic [TCA], a selective serotonin reuptake inhibitor [SSRI], or lithium) as continuation therapy. Recent studies show an alarmingly high relapse rate after ECT despite conventional continuation pharmacotherapy (C-PHARM). Continuation ECT (C-ECT) is also in widespread clinical use; however, its efficacy and safety have never been rigorously tested.

Investigators at four sites (Mayo Clinic, UMDNJ-New Jersey Medical School, Zucker Hillside Hospital, and University of Texas SW Medical Center, Dallas) randomize patients to receive either C-ECT or an aggressive pharmacological strategy (nortriptyline and lithium in combination, [NOR-Li]) for 6 months following response to acute phase ECT. Raters at each site evaluate symptoms and side effects. On the basis of edited videotapes obtained at regular intervals, a site-independent, blinded evaluator also assesses symptoms. A neuropsychological battery is administered prior to acute phase ECT, shortly after the ECT course, 3 months after the end of the acute phase treatment, and at the end of the 6-month continuation trial. These continuation therapies are compared in their effects on relapse, cognitive performance, global functioning, side effects, and perceived health status. NOR and Li levels are optimized by blood level monitoring. Bilateral ECT, at progressively increasing intervals, are used for C-ECT. Methods are included to ensure the integrity of clinical diagnoses, symptom severity assessment, data collection and entry, and treatment delivery. In all patients, surreptitious use of prescription or recreational drugs is monitored by urine testing.