More than 30% of individuals who experience major depressive episodes (MDEs) do not achieve remission after several trials of antidepressants. Such treatment-resistant depression (TRD) has conventionally been managed by Electroconvulsive therapy and more recently with ketamine. However, no study has yet quantified the overall treatment effect sizes of efficacy and safety outcomes between ketamine and ECT.
A recently conducted meta-analysis and systematic review published in JAMA Psychiatry has shown that that ECT may be superior to ketamine for improving depression severity in the acute phase.
The study included 6 clinical trials comprising 340 patients and efficacy outcomes included depression severity, cognition, and memory performance. Safety outcomes included serious adverse events (eg, suicide attempts and deaths) and other adverse events.
The overall pooled SMD for depression symptoms for ECT when compared with ketamine was −0.69, suggesting an efficacy advantage for ECT compared with ketamine for depression severity.
Any virtues with ketamine use?
While the meta-analysis suggests that ECT may be superior to ketamine in terms of efficacy, treatment options should still be individualized and patient-centered because ketamine's faster antidepressant effects may still be desirable for certain patients with severe MDE who require quick recovery from the severity of depression.
"For instance, 3 studies qualitatively reported that ketamine had more rapid antidepressant effects than ECT during the initial course of treatment sessions, whereas 1 study found that patients receiving ECT recovered more quickly than those receiving ketamine", note authors.
What about cognitive effects?
Because of underpowered study designs, no firm conclusions regarding cognition and memory performance can be made in this meta-analysis.
An important consideration for clinicians and patients with serious depression is the comparative tolerability and safety of ketamine vs ECT. The provision of ketamine only involves the administration of a low dose of anesthesia medicine, while the provision of ECT involves the administration of a full dose of anesthesia plus an electrical stimulus that induces a seizure. Hence, it is expected that ketamine would be better tolerated and safer than ECT.
To conclude, although ECT may be more efficacious than ketamine in the acute phase, treatment options should be individualized and patient-centered, considering different adverse effect profiles and patient preferences.
Source: JAMA Psychiatry: doi:10.1001/jamapsychiatry.2022.3352