Electroconvulsive Therapy: Schizophrenia
Evidence for Acute-Phase Efficacy
Although the first use of ECT was reported in patients with schizophrenia, it was not long before it was appreciated that the efficacy of ECT in schizophrenia was generally less than that in patients with mood disorders. The development of effective antipsychotic drugs, beginning in the late 1950s, led to a number of clinical trials comparing their primary treatment efficacy with that of ECT. With most of these studies reporting that pharmacological agents were at least as effective as ECT alone, the use of ECT for the treatment of schizophrenia steadily declined. More recently, however, there has been a growing interest in the antipsychotic effects of ECT in combination with antipsychotic pharmacological agents (American Psychiatric Association Committee on ECT 2000). In this regard, a number of well-controlled studies have established that when the patient is in a distinct acute episode of illness that is marked by prominent psychotic symptoms, this combination treatment may be more effective than either antipsychotic medication or ECT alone (Klapheke 1993; Sajatovic and Meltzer 1993).
The role of ECT in the treatment of medication-resistant cases not presenting with an acute exacerbation is unclear. Although some practitioners believe that all such medication-resistant schizophrenic patients should undergo a trial of ECT at some point during their lifetime, others do not. In particular, no efficacy has been claimed regarding “negative,” or “deficit,” symptoms. In any event, one would generally first consider trials of atypical antipsychotic medications. These latter agents, including clozapine, have also been combined with ECT with reports of success (Benatov et al. 1996).
Because of the evidence pointing to a relatively good response to ECT in mood disorders, it is not surprising that patients with schizophreniform disorder or schizoaffective disorder appear to respond to ECT more readily than do patients with schizophrenia. Indeed, data from retrospective series and case reports have supported this position (Fink and Sackeim 1996; Krueger and Sackeim 1995).
Evidence for Continuation/Maintenance-Phase Efficacy
Perhaps even more so than with mood disorders, the risk of recurrence is extremely high in schizophrenia, particularly among the relatively medication-resistant population who are generally referred for ECT. Many of these individuals have already failed to respond to prophylaxis with antipsychotic drugs, are known to be noncompliant with these agents, or are intolerant of their use. This situation once again raises the issue of C/M ECT, and a recent study reported a prophylactic benefit for the combination of continuation ECT and antipsychotic medication in medication-resistant individuals with schizophrenia (Chanpattana et al. 1999).
Revision date: June 22, 2011
Last revised: by David A. Scott, M.D.