The use of ketamine as an antidepressant: a systematic review and meta‐analysis
Human Psychopharmacology Clinical and Experimental – April 07, 2015
Source: OpenAlex
Summary
A meta-analysis of 21 studies, involving 437 patients, reveals a single ketamine infusion can significantly alleviate major depressive disorder and bipolar disorder symptoms within 4 hours, lasting up to 7 days. Originally an anesthesia medicine, ketamine shows powerful antidepressant effects. Repeat infusions yielded larger effect sizes for treatment of Major Depression. The percentage of males predicted antidepressant response at 7 days. This internal medicine and psychology research highlights ketamine's promise in mental health research topics; future placebo-controlled studies will clarify its long-term efficacy for bipolar disorder and treatment.
Abstract
Objective The current meta‐analysis examines the effects of ketamine infusion on depressive symptoms over time in major depressive disorder (MDD) and bipolar disorder (BD). Methods Following a systematic review of the literature, data were extracted from 21 studies ( n = 437 receiving ketamine) and analysed at four post‐infusion time points (4 h, 24 h, 7 days and 12–14 days). The moderating effects of several factors were assessed including: repeat/single infusion, diagnosis, open‐label/participant‐blind infusion, pre–post/placebo‐controlled design and the sex of patients. Results Effect sizes were significantly larger for repeat than single infusion at 4 h, 24 h and 7 days. For single infusion studies, effect sizes were large and significant at 4 h, 24 h and 7 days. The percentage of males was a predictor of antidepressant response at 7 days. Effect sizes for open‐label and participant‐blind infusions were not significantly different at any time point. Conclusions Single ketamine infusions elicit a significant antidepressant effect from 4 h to 7 days; the small number of studies at 12–14 days post infusion failed to reach significance. Results suggest a discrepancy in peak response time depending upon primary diagnosis — 24 h for MDD and 7 days for BD. The majority of published studies have used pre–post comparison; further placebo‐controlled studies would help to clarify the effect of ketamine over time. Copyright © 2015 John Wiley & Sons, Ltd.