[Night sleep disorders during recovery of severe head injuries (author's transl)].

In 16 young (15 to 25 years) patients, sleep recordings have been performed one month (group T1, 10 cases) or 6 months (group T6,6 cases) after recovery of consciousness following severe head injury. Group T1 can be divided in two subgroups according to clinical and EEG datas: T1A (4 cases) with long duration of coma (15 to 40 days) and low level of brain stem dysfunction (diencephalic). In group T6 every duration of coma and level of dysfunction are present. Percentage of intrasleep wakefulness and number of awakenings are very increased in group T1A (31,5% and 24); these datas are less increased in group T1B (10,1% and 19) and T6 (11.8% and 19). Percentage of REM sleep is very low in group T1A (9,57%) and T1B (12,65%) because of short duration of each phase. In group T6 REM sleep is close to control subjects (16,15% and 20,52%). These results are compared to those reported in normal or insomniac subjects of same age or much older. They are very similar to sleep perturbations observed in elderly (70 years) but normal people. This may evoke an early ageing of brain stem structures involved in organization of wakefulness-sleep rhythm and REM sleep.