Experimental Therapeutics and Pathophysiology Branch, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA.
2 papers in the library · 22 citations · publishing 2024-2025
Ketamine, a drug that modulates the glutamate system, is linked to changes in sleep, depression, and suicidal thoughts. In a randomized, double-blind, crossover trial, 36 people with treatment-resistant major depression and 25 healthy volunteers underwent polysomnography before and after receiving ketamine or placebo. At baseline, those with depression had less total sleep time and shorter REM latency. Ketamine increased slow-wave (delta) brain activity early in the night and both alpha and delta activity later, compared to placebo. However, ketamine did not significantly alter sleep arousal metrics or mediate its antidepressant or anti-suicidal effects through sleep changes. The findings suggest sleep-related variables are part of broader neurobiological shifts after ketamine.
People with treatment-resistant depression show higher REM density in the first REM period and shorter REM latency than healthy volunteers, while total night REM density does not differ. Ketamine treatment reduces REM density in the first REM period but does not change total night REM density or REM latency. Baseline REM density in the first REM period moderately predicts whether a person will respond to ketamine, with higher levels indicating greater likelihood of response. This marker could help identify individuals most likely to benefit from ketamine therapy.