Clinical efficacy of formula-based bifrontal versus right unilateral electroconvulsive therapy (ECT) in the treatment of major depression among elderly patients: a pragmatic, randomized, assessor-blinded, controlled trial

Abstract

Background: No prior study has compared the efficacy of bifrontal (BF) vs right unilateral (RUL) electroconvulsive therapy (ECT) by including the subgroup that is most likely to receive it: only elderly patients with major depression (MD).

Methods: This single-site, randomized, assessor-blinded, controlled trial was conducted from 2009 to 2013. Seventy-three elderly patients with MD, unipolar and bipolar, were treated with a course of formula-based BF ECT or RUL ECT. The 17-item Hamilton Rating Scale for Depression (HRSD17) was used to measure efficacy. Safety was assessed with the Mini Mental State Examination (MMSE).

Results: Both electrode placements resulted in highly significant downward trends in symptom severity (all p<0.001), with a non-significant difference between methods (p=0.703). At the end of the ECT course, response rates for the BF and RUL group were 63.9% and 67.6%, respectively. Short-term remission, defined as an HRSD17 score≤7, was achieved in 14 (38.9%) patients in the BF group and 19 (51.4%) patients in the RUL group. Global cognitive function, as measured by the MMSE, did not deteriorate in the two treatment groups.

Limitations: The small number of subjects may have led to reduced power to detect real differences. The MMSE is not sufficient to ascertain the negative effect of ECT on cognition.

Conclusions: This study indicates that formula-based BF and RUL ECT are equally efficacious, and that remission rates of formula-based dosing are lower than those previously reported for titrated dosing, in a clinical sample of elderly patients with MD.

Trial registration: ClinicalTrials.gov NCT01559324.

Keywords: Bifrontal ECT; Electroconvulsive therapy; Major depression; Old age; Right unilateral ECT; Treatment efficacy.