Cognitive side-effects are the most troublesome side-effects after electroconvulsive therapy (ECT). Efforts to reduce side-effects, maintaining a high efficacy are ongoing. Cognitive effects of bifrontal and unilateral ultra-brief pulse ECT were compared, in the treatment of patients with a depressive episode.

Sixty four patients with a depressive episode that was highly medication refractory, and with a high degree of comorbidity completed a course of bifrontal ECT at 1.5 times seizure threshold (ST) or unilateral ECT at 6 times ST, with a pulse width of 0.3 msec by random assignment. An extensive cognitive battery was performed at baseline and at 1 and 6 weeks post-treatment, by a blinded rater.

At the end of the treatment course, 78.1% of patients responded (≥ 50% decrease HDRS-scores). There was a significant increase in global cognitive function (MMSE), verbal memory (RAVLT), attention (CPT), executive function (WCST) and autobiographical memory (AMI). Patients reported a significant increase of their subjective memory function both during and after the ECT-course. There were no significant differences between the patients given bifrontal ECT and those given unilateral ECT.

Bifrontal and unilateral ultra-brief pulse ECT are effective treatment techniques that do not cause measurable cognitive side-effects or cognitive complaints.