Most studies of the effects of ECT in refractory patients have been conducted in patients who have failed to respond to monotherapy with an antidepressant, either a tricyclic or an MAOI. Response rates ranging from 50% to 89% indicate that ECT may be effective in patients suffering from refractory depression. However, no studies have adequately evaluated patients with "core refractory" depression, (ie, those who have failed to respond to multiple courses and combinations of drug therapies). In the absence of partial response to 6 unilateral treatments, a full course of bilateral treatment should be instituted, which can increase responsiveness.[14,49]
Although continuation pharmacotherapy usually is effective in nonrefractory depressed patients following ECT, a sizable number of depressive patients will relapse rapidly following acute response. Shapira and coworkers followed 28 depressed patients for up to 6 months after successful treatment with ECT and lithium maintenance treatment. Eight patients relapsed during this period. Factors associated with early relapse included a relatively short duration of the index episode of depression, a prior depression in the preceding 12 months, and the failure of an adequate trial of antidepressant medications prior to ECT.
An alternative to resumption of pharmacotherapy following ECT in formerly nonresponsive patients is continuation ECT. Petrides and colleagues followed 21 patients receiving continuation ECT after initial positive response. Relapse occurred in 33%, a rate lower than expected for this population. The relapse rate for patients with delusional depression was 42%, which was markedly lower than the 95% found in patients maintained on continuation pharmacotherapy. Continuation ECT has a strong potential for benefit in refractory depression, but further research is needed.
Medscape Psychiatry & Mental Health eJournal. 1996;1(6) © 1996 Medscape
Cite this: Treatment-Resistant Depression: Therapeutic Approaches - Medscape - Dec 16, 1996.