Meta-analysis of short- and mid-term efficacy of ketamine in unipolar and bipolar depression
Choucha, W., Fossati, P., Romeo, B., Rotge, J.
This meta-analysis (2015) of six randomised, double-blind, placebo-controlled trials (n=101) examined the short-and mid-term efficacy of ketamine (bipolar) to depression. Ketamine effectively reduced symptoms in unipolar depression for seven days, , whereas the maintenance of its efficacy in bipolar depression failed to reach significance after 4 days.
Abstract
Introduction: Among treatments currently assessed in major depression, ketamine, has been proposed of great interest, especially because of its very rapid action. However, the time-course of the antidepressive action of ketamine remained unclear. In the present meta-analysis, we provided a clear and objective view regarding the putative antidepressive effect of ketamine and its time-course.Methods: We searched the MEDLINE and PsycINFO databases through December 2013, without limits on year of publication, using the key words ketamine and synonyms for mood disorder or episode. Six randomized, double-blind and placebo-controlled trials of ketamine in major depression (n=103 patients) were thus identified. Authors were contacted and they all provided original data necessary for this meta-analysis. Standardized mean differences (SMD) were calculated between the depression scores in ketamine and placebo groups at days 1, 2, 3-4, 7 and 14.Results: Ketamine showed an overall antidepressive efficacy from day 1 to day 7. However, the maintenance of its efficacy over time failed to reach significance in bipolar depression after day 3-4. Significant SMDs were not explained by demographic or clinical characteristics of included samples.Discussion: The present meta-analysis provides a high level of evidence that ketamine has a rapid antidepressive action during one week, especially in unipolar disorder.