Self-assessed remission rates after electroconvulsive therapy of depressive disorders

Electroconvulsive therapy (ECT) effectively treats severe depression, but not all patients remit. The aim of the study was to identify clinical factors that associate with ECT-induced remission in a community setting.

Depressed patients who underwent ECT in 2011-2014 were identified from the Swedish National Quality Register for ECT. Remission was defined as self-rated Montgomery-Åsberg Depression Rating Scale scores of 0-10 after ECT. Other registers provided data on previous antidepressant use, comorbidities, and demographics.

Of 1671 patients fulfilling the inclusion criteria, 42.8% achieved remission. Older age, education length over 9 years, psychotic symptoms, shorter duration of preceding antidepressant use, pulse width stimulus≥0.50ms, absence of substance use disorders, anxiety diagnosis, lamotrigine, and benzodiazepines, were associated with remission.

This study shows that psychotic subtype of depression and older age are clinically relevant predictors of a beneficial ECT effect. Additionally, ECT outcomes can be further improved by optimizing the treatment technique and concomitant medication.