Eveningness Chronotype Preference among Individuals at Clinical High Risk for Psychosis.

Background: Circadian rhythm disturbances are frequently implicated in psychosis. Indeed, research has sug-gested several avenues by which circadian rhythms may play a mechanistic role as well as contribute to clinical outcomes. Despite its potential role as a risk factor, little is known about circadian rhythm disruption among individuals at clinical high risk (CHR) for psychosis, clinical correlates, or specificity to the psychosis risk syndrome. Methods: Eighty-four CHR, 74 individuals with depressive disorders (DD), and 101 non-psychiatric controls (NPC) participated in structured clinical interviews and provided self-reports of chronotype preference. Clinical (positive, negative, anxious, and depressive symptoms) and social functioning outcomes were self-reported and/ or clinician-rated. Analyses of covariance controlling for demographics examined group differences in chro-notype preference, and partial Pearson correlations evaluated associations with clinical/functional outcomes. Results: Group differences were observed (F(11, 246) = 8.05, p < .001) with CHR and DD individuals indicating greater eveningness preference compared to NPC. A follow-up sensitivity analysis examining CHR participants with (n = 25) and without (n = 59) depressive disorders indicated no difference in chronotype preference (F (10,72) = 0.00, p = .99). Greater eveningness preference was related to greater negative symptoms (i.e., avo-lition; r =-0.25) and anxiety (r =-0.34) among CHR individuals. Conclusions: CHR and DD display greater preference for eveningness chronotype compared to NPC indicating the disruption is associated with a range of mental health concerns, and not specific to the psychosis-risk syndrome. However, comorbidity with DD did not appear to be driving the finding in the CHR group. Further research may examine shared versus non-shared underlying mechanisms contributing to chronotype preference across psy-chiatric presentations.