The use of ketamine as an antidepressant: a systematic review and meta‐analysis
Caoimhe M. Coyle, Keith R. Laws
Human Psychopharmacology Clinical and Experimental April 7, 2015 DOI: 10.1002/hup.2475 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Meta-analysis Peer reviewed |
|---|---|
| Sample size | 437 |
| Population | People with major depressive disorder or bipolar disorder receiving ketamine infusion |
| Intervention | Ketamine infusion |
| Duration | Assessed at 4 hours, 24 hours, 7 days, and 12–14 days post-infusion |
| Topics | Depression Ketamine Esketamine |
| Keywords | Antidepressant Meta-analysis Placebo Anesthesia |
| Citations | 279 |
| Key findings | Single ketamine infusions produce a significant antidepressant effect from 4 hours to 7 days, with larger effects from repeated infusions and a possible difference in peak response time by diagnosis. |
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.
Comparable studies
Other systematic reviews and meta-analyses on ketamine for depression, most cited first.