Characterizing Response to Electroconvulsive Therapy in Schizophrenia

Researchers at the American Psychiatric Association 2023 Annual Meeting featured a retrospective study on response rate and response predictors with bilateral electroconvulsive therapy (ECT) among patients with schizophrenia.

According to data gathered by Chanaichon Ruangsetakit and colleagues, ECT is an effective treatment for patients with schizophrenia. In addition, they found speed of response to ECT was associated with the number of failed antipsychotics prior to starting ECT.

Investigators enrolled 46 patients undergoing bilateral ECT from Jan. 2013 to June 2022 and reviewed demographic, clinical, ECT, and treatment response findings. Response was defined as a 40% reduction in Brief Psychiatric Rating Scale (BPRS) psychotic symptom subscale after the last treatment session.

Patients had the following reasons for undergoing ECT:

  • Nonresponse to antipsychotics (n=27; 58.7%)
  • Agitation (n=11; 23.9%)
  • Psychomotor retardation (n=5; 10.9%)
  • Intolerance to psychotropic medication side effects (n=3; 6.5%)

Researchers reported the overall response rate to ECT was 60.9%. Specifically, nine (19.6%) patients responded after three sessions, 17 (37%) after six sessions, 20 (43.5%) after nine sessions, 25 (54.3%) after 12 sessions, and 28 (60.9%) after the final session.

Notably, responders had significantly higher baseline mean BPRS subscale scores at 17.0±5.8 compared with nonresponders at 10.9±6.4 (P<.05). Likewise, responders had significantly longer electroencephalographic seizure duration at 53.9±22.6 compared with nonresponders at 42.7±11.0. Authors noted no associations were observed between demographic or ECT characteristics and treatment response.

In the 28 responders, 20 (71.4%) responded after nine sessions, which the authors categorized as faster responders, compared with the eight (29.6%) patients who responded later (slower responders). Faster responders had a mean number of failed previous antipsychotics of 2.8±1.6 compared with 4.4±1.9 for slower responders (P=.02). Investigators stated the number of prior antipsychotics was associated with speed of response, with an odds ratio of 1.77 (P=.037).

Ultimately, Ruangsetakit and colleagues suggested ECT was an effective option for patients with schizophrenia and that more severe symptoms at baseline might predict response to ECT treatment.