Circadian rhythm of REM sleep of chronic alcoholics during alcohol withdrawal.

Sleep structures were polygraphically investigated during the alcohol withdrawal periods of six male alcoholics. Polygraphic recordings were taken 10 days, 1 month and 3 months after hospitalization. Total sleep time was almost equal among the three recording nights for each patient. Stages 3 and 4 sleep were remarkably reduced on all the recording nights. REM sleep time was normal throughout the study. REM latency decreased in many patients on the 10th day, and gradually increased on the following nights. A very important change was observed in the distribution of REM sleep. Maximal duration was noted in the first REM episode on the 10th day in four of the six. On the second recording night the second REM episode was the longest in five of the six subjects. On the last recording night many patients exhibited a normal distribution of REM sleep. These findings which suggest that the acrophase of REM sleep is advanced by several hours for a few months after alcohol withdrawal have also been observed in patients with endogenous depression. Although our patients did not show any depressive symptoms during the study, one of them developed a severely depressive state after he began to drink alcohol thereafter.