Personality Traits Interact With Sleep and Biological Rhythm in Patients With Bipolar Disorder.

Sleep disturbances and circadian rhythm changes in bipolar disorder (BD) may have behavioral components as well as biological components. This study aimed to examine the relationship between personality traits, sleep and circadian rhythm in BD. A total of 150 participants with BD, and 150 healthy controls completed the Big Five Personality Test-50 (B5PT-50-TR), Biological Rhythm Interview of Assessment in Neuropsychiatry (BRIAN), Functioning Assessment Short Test (FAST), Pittsburgh Sleep Quality Index (PSQI), Young Mania Rating Scale and Beck Depression Inventory. In the BD group, B5PT-50-TR emotional stability and openness subscale scores were significantly lower in comparison with the healthy control group. Agreeableness and emotional stability subscales were covariates for the BRIAN sleep subscale and emotional stability was a covariate for PSQI total score. Emotional instability might be a vulnerability factor for sleep disorders and biological rhythm abnormalities in BD. Improvement in emotional instability may relieve sleep disorders and biological rhythm, thereby leading to better treatment outcomes in BD.