'Rapid speed of response to ECT in bipolar depression: A chart review

Objective: To validate a faster speed of response to electroconvulsive therapy (ECT) for bipolar depression (BPD) compared to major depressive disorder (MDD) Method: Retrospective chart review on an ECT cohort in an academic hospital setting. Speed of response was defined by the number of ECT treatments needed for response or remission. Results: Sixty-four depressed patients were included, of whom 53 (MDD: 40, BPD: 13) could be analyzed. The bipolar group responded faster with a mean difference of 3.3 fewer ECT treatments to meet response criteria (MDD 10.4 vs. BPD 7.1, p = 0.054). When using mixed effects regression models for the response/remitter group (n = 35), a faster response for the bipolar group (AIC 252.83 vs 258.55, χ2 = 11.72, p = 0.008) was shown. Other factors, such as psychotic features or comorbidity, did not influence the speed of response. Conclusion: This chart review of an ECT cohort in an naturalistic academic hospital setting shows an evident and clinically relevant faster speed of response in bipolar depression