Eveningness is associated with poor sleep quality and negative affect in obsessive–compulsive disorder

BackgroundObsessive–compulsive disorder (OCD) is characterized by intrusive thoughts and repetitive behaviors that severely encumber daily functioning. OCD patients seem to exhibit sleep disturbances, especially delayed bedtimes that reflect disrupted circadian rhythmicity. Morningness–eveningness is a fundamental factor reflecting individual variations in diurnal preferences related to sleep and waking activities. Eveningness reflecting a delayed sleep–wake timing has repeatedly been associated with sleep problems and negative affect (NA). Therefore, the aim of this study was to examine the associations between morningness–eveningness, sleep complaints, and symptom severity in OCD patients and compared with a mixed psychiatric control group.Materials and methodsThe data of 49 OCD and 49 mixed psychiatric inpatients (with unipolar depression and anxiety disorders) were analyzed. Patients completed questionnaires regarding morningness–eveningness, sleep quality, nightmare frequency, depression, anxiety, an...