Double-blind randomized controlled study showing symptomatic and cognitive superiority of bifrontal over bitemporal electrode placement during electroconvulsive therapy for schizophrenia

Abstract

Background: Several studies show that bifrontal electrode placement produces relatively fewer cognitive adverse effects than bitemporal placement during electroconvulsive therapy (ECT) in depression. There are no reports comparing these electrode placements in schizophrenia.

Objectives: This study compared the clinical and cognitive effects of bifrontal and bitemporal electrode placements in schizophrenia patients referred for electroconvulsive therapy (ECT).

Methods: 122 schizophrenia patients who were prescribed ECT were randomized to receive ECT with either bifrontal (BFECT; n = 62) or bitemporal (BTECT; n = 60) placement. Their concomitant anti-psychotic medications and the number of ECT sessions were not controlled. Psychopathology was assessed using the Brief Psychiatric Rating Scale (BPRS), Bush-Francis Catatonia Rating Scale (BFCRS), and the Nurse Observation Scale for Inpatient Evaluation (NOSIE). Cognitive functions were assessed 24-h after the final ECT using a battery of tests. Clinical improvement was compared using chi-square test, repeated measures ANOVA and analysis of covariance (ANCOVA). Cognitive adverse effects were compared using t-test.

Results: At the end of 2 weeks (after 6 ECT sessions) 63% and 13.2% of BFECT and BTECT patients respectively had met the response criterion for BPRS (40% reduction in total score; OR = 20.8; 95% CI = 3.61-34.33). BFECT patients showed significantly faster clinical response on BPRS (Time × Group interaction effect: P = 0.001), BFCRS (P < 0.001) and the NOSIE total assets score (P = 0.003). ANCOVA using baseline scores as covariates and treatment-resistance status as between-subject factor showed that BFECT patients had significantly greater improvement in all measures. BFECT patients had significantly higher PGI-memory-scale total score than BTECT patients (t = 5.16; P < 0.001). They also showed superior performance in other cognitive measures.

Conclusions: BFECT results in superior clinical and cognitive outcomes than BTECT in schizophrenia patients referred for ECT.