Role of chronotype in depression.

Depression is a widespread and debilitating mental health disorder affecting millions globally. Chronotype has been increasingly recognized as a significant factor associated with depression. This review aims to comprehensively dissect the role of chronotype in depression, providing insights into the underlying mechanisms linking chronotype to depression, as well as the potential therapeutic implications. Converging evidence indicates that evening chronotype is notably associated with an elevated risk of depression, more severe symptoms, and a higher rate of suicidality, while morning chronotype may exert a protective effect. These findings highlight that chronotype plays a crucial role in the development, manifestation, and management of depression. Nevertheless, some methodological issues of the existing studies (e.g., reliance on self-reported chronotype assessments) should be noted and discussed. Further investigations are warranted to elucidate the intricate mechanisms underlying the relationship between chronotype and depression, establish causal links, and optimize the clinical application of chronotype-based interventions for depression.