A DOUBLE-BLIND, PLACEBO-CONTROLLED EVALUATION OF THE EFFECTS OF ORALLY-ADMINISTERED VENLAFAXINE ON SLEEP IN INPATIENTS WITH MAJOR DEPRESSION

Venlafaxine, a member of a novel chemical class, phenethylamines, is a new antidepressant that inhibits neuronal uptake of serotonin, norepi nephrine, and dopamine (in decreasing order of potency) at doses of 75 to 375 mg per day. Depression and antidepressant drugs are known to m odify human sleep patterns. Our objective in this double-blind, placeb o-controlled study was to assess the effects of venlafaxine on polysom nographic variables by comparing the effects of venlafaxine and placeb o on sleep (hypnographic and all-night electroencephalographic [EEG] s pectral analysis) and clinical measures (Hamilton Rating Scale for Dep ression [HAM-D], Montgomery-Asberg Depression Rating Scale [MADRS], an d Clinical Global Impressions [CGI]) in inpatients with major depressi on (DSM-III-R). Following a 7- to 13-day placebo washout period, patie nts were randomly assigned to receive either placebo or venlafaxine (m aximum dose 225 mg/day) for up to 29 days. Sleep evaluations took plac e at baseline (3 nights immediately before entering the double-blind p hase), after 1 week of treatment, and after 1 month of treatment. Slee p stage parameters and all-night spectral parameters were first tested by analysis of variance for repeated measures and then, if indicated, by two-tailed Student t-test. The results on psychiatric rating scale s showed improvement from baseline in both treatment groups at all tim e points, with improvement tending to be greater in the venlafaxine gr oup. Venlafaxine induced a decrease of sleep continuity (decreased tot al sleep time and increased wake time), an important increase in the o nset latency of rapid eye movement (REM) sleep, and a decrease in tota l REM sleep duration. All-night sleep EEG frequency structure was not modified significantly by venlafaxine treatment as compared with place bo. In conclusion, venlafaxine, despite its novel chemical structure, shows a sleep profile comparable with that of most classical antidepre ssants.