Sleep onset REM periods in obsessive compulsive disorder

Sleep studies in patients with obsessive compulsive disorder (OCD) are sparse and results inconsistent. Moreover, in 3 out of 4 published studies up to 50% of patients suffered from secondary major depression. In this study, 10 inpatients with a DSM-IV diagnosis of OCD without comorbid major depression (Yale-Brown Obsessive Compulsive Scale (Y-BOCS) score > 15; Hamilton Depression Rating Scale (HAMD)-21 total score < 17) and 10 healthy matched controls were included. Polysomnography of patients (7 males, 3 females, 34.5 ± 12.7 years, Y-BOCS: 27.8 ± 4.6, HAMD-21: 13.3 ± 1.9) and controls (7 males, 3 females, 34.4 ± 12.8 years) was recorded, following an adaptation night. Sleep variables did not significantly differ in both groups except that stage 4 sleep was reduced in patients. Three of the patients with OCD, however, exhibited sleep onset REM periods (SOREMPs), i.e. rapid-eye-movement (REM) latencies < 10 min. Obsessive compulsive symptoms were significantly (P < 0.05) more severe in these patients (Y-BOCS: 32 ± 2.0) compared to those without SOREMPs (Y-BOCS 26 ± 4.2). This is, to our knowledge, the first report of sleep onset REM periods in OCD.