Evaluating maintenance electroconvulsive therapy in Bipolar Disorders: 3-year mirror-image study

Abstract

Backgorund: Maintenance electroconvulsive therapy (mECT) is underused in the treatment of bipolar disorder (BD). We aimed to study the real-life effectiveness of mECT in BD.

Methods: Naturalistic 3-year mirror-image study in individuals diagnosed with BD who underwent mECT at a tertiary hospital. Intra-subject comparisons of psychiatric hospitalization were performed using McNemar test. Days and number of psychiatric hospitalizations before and during mECT were compared through wilcoxon signed-rank test. Mean annual days and mean annual number of psychiatric hospitalizations per patient were compared by means of the rate ratio (RR) estimation through a generalized estimating equation (GEE) model.

Results: A total of 43 patients were included and 37 required psychiatric hospitalization during the study. The use of mECT showed an effectiveness of 62.2% for preventing psychiatric hospitalizations (p<0.01). We found significant reduction in days and number of psychiatric hospitalizations during mECT compared to before mECT (p<0.01). Comparison of the 3-year period before/during mECT showed a reduction in mean annual days (RR=0.14; 95%CI: 0.07-0.29) and mean annual number (RR=0.24; 95%CI: 0.13-0.43) of psychiatric hospitalizations, without substantial changes for adjusted models for gender and age of onset of the illness.

Limitations: The main limitations of this study consisted of the mirror-image retrospective naturalistic study design, the relatively small sample size, and possibly patient selection bias.

Conclusions: mECT reduced the number of psychiatric hospitalizations and hospitalization days in BD. The use of mECT outlines a mood stabilizing effect in BD. This naturalistic study supports the effectiveness of mECT in BD across several mood states.