Biological rhythm disturbance in remitted bipolar patients

Bipolar patients (n = 107) experienced greater biological rhythm alterations than the control group (n = 100) (BRIAN total scores 35.36 ± 7.11 vs. 32.48 ± 6.10, t = 6.912, p = 0.002, Cohen's d = 0.43, r = 0.21). In particular, patients were more impaired than the control group with regard to sleep/social (14.67 ± 4.14 vs. 13.49 ± 2.91, t = 10.61, p = 0.018, Cohen's d = 0.33, r = 0.16) and activity (8.49 ± 2.51 vs. 7.07 ± 2.13, t = 3.90, p = 0.001, Cohen's d = 0.61, r = 0.29) domains. Furthermore, a significant correlation was found between biological rhythms with residual depressive symptoms (r = 0.459, p < 0.001) and functioning (r = 0.432, p < 0.001). These findings suggest a potential link between biological rhythms and the pathophysiology of bipolar disorder. It highlights the importance of novel instruments (e.g., BRIAN) which allow us to assess biological rhythm disturbance in psychiatry. Finally, specific psychosocial interventions focused on lifestyle regularity may be considered as a supplemental treatment of bipolar illness episodes.