Circadian Cycle in Patients with Bipolar Disorder

Objective: To examine the distribution of chronotypes (morning, evening, intermediate) in patients with bipolar disorder and their associations with sociodemographic factors, clinical history, and comorbidities. Results: Chronotype. Distribution: Morning 74%, Evening 15%, Intermediate 11%. Bipolar type I: Morning 34.6%, Evening 8.6%, Intermediate 32.1%. Bipolar type II: Morning 11.1%, Evening 0%, Intermediate 13.6%. Significant associations: Morning chronotype linked to fewer suicide attempts (p = 0.034). Fewer depressive episodes in morning chronotype vs. evening/intermediate (p < 0.001). No significant associations: Chronotype vs. gender, age, marital status, education, occupation, medical comorbidities, number of manic/hypomanic episodes. Discussion: Unexpected. Finding: Predominance of morning chronotype, contrary to literature which often finds evening preference in bipolar disorder. Possible Explanations: Lithium and mood stabilizers’ effect on circadian genes, Long-term psychiatric follow-up and structured daily routines, Social/work constraints in an urban population. Low evening chronotype proportion: May reflect stable/post-acute phase, prior hospitalization routines, or underreporting.