Association Between Chronotype and Dysfunctional Beliefs About Sleep in Psychiatric Outpatients With Sleep Disturbance

Objective: This study investigated the association between chronotype and dysfunctional sleep-related beliefs in psychiatric outpatients presenting with sleep disturbance. Methods: This study analyzed medical records of 117 psychiatric outpatients with sleep disturbance (mean age 54.24±15.02 years; 65.8% female). Chronotype was assessed using the reduced Morningness-Eveningness Questionnaire (rMEQ). Sleep-related beliefs were evaluated using the Dysfunctional Beliefs and Attitudes about Sleep scale (DBAS-16). The relationship between chronotype and sleep-related beliefs and the interaction effect of age on their relationship were examined. Results: There was a significant negative association between rMEQ and DBAS-16 (r=-0.267, p<0.01, n=117), indicating that a stronger evening preference was associated with more pronounced dysfunctional sleep beliefs. This association remained significant after adjusting for age and sex (β=-0.299, p<0.01) or after controlling for depression, anxiety, insomnia, daytime sleepiness, and sleep quality (β=-0.277, p<0.01). The rMEQ score was independently associated with DBAS-16, accounting for 7% of the total variance. This negative relationship remained robust even after adjusting for all potential covariates including clinical and demographic factors (β=-0.277, p=0.003). There was a significant interaction of age group on the association between rMEQ and DBAS-16 (F(4, 108)=3.211, p=0.016). The effect of chronotype on dysfunctional beliefs was more evident among middle-aged and older patients. Conclusion: Chronotype is independently associated with dysfunctional beliefs about sleep in psychiatric outpatients with sleep disturbance.