Clinical characteristics of circadian rhythm sleep disorders.

From our practice at the sleep disorders clinic in Kohnodai Hospital, National Center of Neurology and Psychiatry (NCNP), we report the clinical characteristics of circadian sleep-wake rhythm disorders. Nearly 90% of circadian rhythm sleep disorders were diagnosed as delayed sleep phase syndrome (DSPS) or as non-24 sleep-wake syndrome (non-24). While DSPS was equally common in males and females, non-24 was more frequently seen in men. It was of psychiatric interest that a considerable number of patients had depressive states in the course of their circadian rhythm sleep disorders. Difficulty in adapting to social life was more severe in patients with non-24 than in those with DSPS.