Indexed on: 05 May '09Published on: 05 May '09Published in: Sleep and Biological Rhythms
The primary symptom of circadian rhythm sleep disorders (CRSDs) is the inability to sleep during the desired sleep time. CRSDs are divided into two broad classes: (i) disorders not related to forced alterations of the sleep-wake schedule or light-dark cycle (including advanced sleep phase disorder [ASPD], delayed sleep phase disorder [DSPD], non-entrained type [NET], and irregular sleep-wake rhythm [ISWR]); and (ii) disorders related to forced alterations of the sleep-wake schedule or light-dark cycle (including shift work sleep disorder [SWSD], jet lag disorder [JLD], and CRSDs related to diseases and medications). DSPD and ASPD are the common primary circadian rhythm disorders. We discuss the recent developments in the pathogenesis, diagnosis, and management of CRSDs.