Sleep-onset REM sleep in obsessive compulsive disorder

Sleep studies in obsessive compulsive disorder (OCD) are sparse and had contradictory results. Therefore, polysomonographic recordings were conducted in 10 inpatients with a DSM-IV diagnosis of OCD (Yale-Brown Obsessive Compulsive Scale (Y-BOCS) score >15; HAMD–21 total score <16) and 10 healthy matched controls, following an adaptation night. The following sleep variables were calculated: time in bed (TIB), total sleep time, time awake, sleep onset latency, SWS latency, REM latency, sleep efficiency, absolute time spent in each sleep stage, and number of awakenings. Group differences were assessed using a MANOVA. In patients (7, males, 34.5±12.7 years) Y-BOCS scores ranged from 22 to 34 (27.8±4.6) and HAMD–21 total scores from 9 to 16 (13.3±1.9). There was no significant difference in any of the determined sleep variables between OCD-patients and healthy controls (7 males, 34.4±12.8 years). However, three OCD-patients but none of the healthy controls had an sleep-onset REM sleep, i.e. a REM latency <10 min. In these patients obsessive compulsive symptoms were severe to extreme (Y-BOCS total score 30, 32, 34). The findings suggest that sleep-onset REM sleep may occur in OCD, most probably in patients severely affected.