An Overview of Sleep and Circadian Rhythms in Bipolar Disorder

Abstract

Since the conception of bipolar disorder (BD) as a psychiatric condition, sleep and circadian rhythm disruptions have been cardinal symptoms of the disorder. Current nosologies recognise this and such disruptions form part of the diagnostic criteria for both manic and depressive episodes. However, despite their historical precedence and their importance for people with BD, sleep and circadian rhythms are often underappreciated in bipolar research. In this review we summarise key research findings about the role of sleep and circadian rhythms in BD. The areas covered include the presentation and comorbidity of sleep and circadian disorders in BD, relevant risk factors, and finally the assessment and treatment of sleep and circadian disruptions in both patients and those at-risk. Recommendations for future research focus on routine and rigorous assessment of sleep and circadian rhythms in BD, investigations into the causal ordering of sleep, circadian and mood symptoms, their use to identify and assist people at-risk of BD, and the integration of sleep and circadian interventions in treatment plans for people with BD.