Chronotype in persons with depressive or anxiety disorders

background Being a morning or evening type, or ‘chronotype’ might be linked to psychopathology. aims We examined the association between chronotype and depressive and anxiety disorders in a large cohort study, while taking into account relevant sociodemographic, somatic health, and sleep characteristics, as well as type and severity of disorder and the use of psychotropic medication. Method Data from the baseline and two-year assessment from the Netherlands Study of Depression and Anxiety (NESDA) were analyzed. Included were 414 controls without lifetime psychiatric disorders, 771 subjects with remitted and 639 subjects with current depressive and/or anxiety disorders. Psychiatric diagnoses were based on DSM-IV criteria. Chronotype was measured with the Munich Chronotype Questionnaire. Results Current depressive and/or anxiety disorders were significantly associated with an evening chronotype (β=.10, p<.001), also after adjustment for sociodemographic, somatic health and sleep factors (β =.12, p<.001). Chronotype was not significantly different in persons with remitted depressive and/or anxiety disorders as compared to controls. Conclusions Current depressive and anxiety disorders are associated with an evening chronotype indicative of a phase delay in circadian chronotype. Further research is needed to determine if a later chronotype is a vulnerability factor for or a consequence of psychopathology. Chapter 6