Differential effects of trimipramine and fluoxetine on sleep in geriatric depression

The effects of trimipramine, a tricyclic antidepressant (TCA) with atypical pharmacological properties, and fluoxetine, a selective serotonine reuptake inhibitor (SSRI), were compared in an exploratory analysis using mood and polysomnographic parameters during a six-week double-blind trial in 19 depressed geriatric patients. In sleep EEG measures, trimipramine demonstrated clear-cut effects on sleep measures resulting in higher values for sleep efficiency, total sleep time, stage 2 sleep, and shorter wake time. Under fluoxetine treatment, the proportion of REM sleep was decreased and REM latency was lengthened, whereas no change in REM sleep parameters was observed in the trimipramine group. The present data suggest that early antidepressant effects of medication occur independently of drug-induced changes in objective measures of sleep, i.e. suppression of REM sleep.