June 6, 2007 (San Diego) — For patients with major depression, relapse rates after acute electroconvulsive therapy (ECT) are higher without maintenance medications, and the lowest rates of relapse appeared to occur in patients who received combination therapy including lithium.

The findings were presented here at the American Psychiatric Association 2007 Annual Meeting.

The success of ECT in acute cases of depression is commonly followed by a high relapse rate, up to 100%, the researchers, with lead author Jan Di Pauli, MD, a psychiatrist at the Regional Hospital Rankweil, in Austria, point out. Among the different strategies developed to minimize relapse rates is the use of maintenance medications following ECT; however, the optimal medication has yet to be determined.

To assess outcomes after ECT, the authors used follow-up data from a previous randomized double-blind study of 92 patients with major depression; the trial had been designed to evaluate the optimal stimulation placement of ECT. The aim of this follow-up study was to assess the outcome of patients after a successful course of ECT.

Higher Relapse Without Lithium

All 92 patients had major depression and were stimulated 6 times either unilaterally (2.5 times seizure threshold) or bifrontally (1.5 times threshold). Depending on clinical status following these 6 sessions, patients received further ECT unilaterally, bifrontally, or bilaterally and were followed up between the fifth and seventh month after treatment. Patients, their psychiatrists, and study raters all completed semistructured questionnaires to assess outcome, maintenance therapy, and patients' attitude.

The patients were first evaluated by the study nurses, then treated with ECT; after 6 sessions the patients were reevaluated, then treated by their own psychiatrists; after 6 months the study nurses (raters) contacted the patients without consulting the questionnaires sent to the psychiatrists and the patients.

There were 88 questionnaires returned. According to the 57 completed questionnaires used for the 6-month outcome analysis, 28 patients were taking lithium, 29 were not. Of those on lithium, 32% (9) relapsed, while 62% (18) of the group not on lithium relapsed.

According to Dr. Di Pauli, "The relapse rate without lithium was much higher; for all patients the relapse rate is highest within the first 2 months after treatment. There were 71 patients on a combination therapy of at least 2 antidepressants, a therapy that is not evidence based." Currently recommended therapy is 1 antidepressant with or without lithium.

The researchers concluded that a lithium combination therapy seems more effective following acute ECT in minimizing relapse rates.

Prospective Data Needed

George Nikopoulos, MD, a psychiatrist in Salt Lake City, Utah, who is experienced in ECT treatment, commented, "The published literature is small on maintenance ECT. We customize it [the schedule] to individual patients. The majority are severely treatment-resistant. This should have been a prospective study; some of these patients just happened to be on lithium; we don't know whether that made a significant difference."