Electroconvulsive Therapy: Manic Episodes

Evidence for Acute-Phase Efficacy
ECT is highly effective in its ability to induce a remission in manic states, with 80% of patients showing marked improvement (Mukherjee et al. 1994). The relative efficacy of ECT versus a lithium/antipsychotic combination was more recently the subject of two controlled investigations. The first study (Small et al. 1988), which allowed the use of antipsychotics with ECT, found that ECT plus antipsychotic was at least as effective as lithium plus antipsychotic, with various trends in the data favoring ECT. The second trial (Mukherjee 1994), carried out in patients whose depression was initially nonresponsive to either lithium or an antipsychotic, showed a 59% incidence of marked response to ECT alone compared with a 0% incidence of response to lithium plus the antipsychotic. These studies provide additional evidence that ECT is demonstrably effective in mania but raise as-yet-unanswered questions concerning whether antipsychotic agents might potentiate the antimanic response to ECT and whether the response is diminished in patients who are medication-resistant during their current episode.

Despite its efficacy in mania, ECT is currently used primarily for patients who are resistant or intolerant to alternative treatments or in cases when there is an urgent need for a rapid response (American Psychiatric Association 1994b). This pattern of use probably represents a relative underutilization of this treatment modality. A case discussion describing the use of ECT in the treatment of mania is provided at the end of this chapter.

No direct comparison of ECT and anticonvulsant antimanic agents has been carried out, although the typical efficacy rate with ECT appears to be considerably higher than that reported with such medications (Mukherjee et al. 1994).

Other than anecdotal reports, no studies have addressed the antimanic efficacy of ECT in patients with rapid-cycling bipolar disorder. When used in this condition, ECT, like alternative treatments, probably loses its efficacy over repeated episodes, at least for some patients. ECT has been reported to be efficacious in patients with schizoaffective disorder, with a likelihood of improvement that is intermediate between that observed in patients with primary mood disorders and that found in patients with schizophrenia (see below). Finally, ECT has been reported to be beneficial in the treatment of catatonic excitement, a rare condition that can be difficult to distinguish from a severe manic state.

Evidence for Continuation/Maintenance-Phase Efficacy

As with major depressive episodes, a single course of ECT does not prevent recurrence of manic episodes. Generally, ECT responders are given antimanic (and often other) pharmacological agents after completion of the ECT course. However, there has been a practice of using continuation ECT for this purpose in patients who have a history of either no benefit from or intolerance to medication treatment. Unfortunately, the use of C/M ECT in the treatment of patients with bipolar disorder has been so little studied that almost nothing appears on this topic in the literature (Vanelle et al. 1994). Conceptually, it would be expected that prophylactic ECT would be beneficial, although a definitive answer cannot yet be given.