Both electroconvulsive therapy (ECT) and subanesthetic intravenous ketamine are presently used to treat treatment-resistant major depression, although their relative efficacy is unknown.

The research was an open-label, randomized, noninferiority experiment including individuals with treatment-resistant major depression who were referred to ECT clinics. Patients with treatment-resistant major depression without psychosis were enrolled and randomly randomized to either ketamine or ECT in a 1:1 ratio. During the first three weeks of therapy, individuals either got ECT three times per week or ketamine twice per week.

A total of 403 patients were randomly randomized to one of five study locations; 200 were assigned to the ketamine group and 203 to the ECT group. After 38 patients withdrew before the start of the allocated therapy, 195 patients received ketamine, and 170 received ECT. 

The ketamine group had a response rate of 55.4%, whereas the ECT group had a response rate of 41.2%. After 3 weeks of therapy, ECT appeared to be related to a decline in memory recall, with modest recovery during follow-up. The two experimental groups improved similarly in terms of patient-reported quality of life. ECT was linked to musculoskeletal side effects, whereas ketamine was linked to dissociation.

The study revealed that ketamine was not inferior to ECT as a treatment for treatment-resistant major depression without psychosis. IV ketamine and ECT both enhanced the quality of life in non-psychotic treatment-resistant major depression.

(Source: https://www.medpagetoday.com/meetingcoverage/apa/104691

https://www.nejm.org/doi/full/10.1056/NEJMoa2302399)