Chronotype and Psychiatric Disorders – An Updated Review

Abstract Purpose of Review Chronotype is increasingly recognized as relevant to a range of psychiatric conditions, but its clinical significance and mechanistic role remain poorly understood. This review summarizes recent evidence on chronotype and psychiatric disorders published since 2018, and highlights key developments in study design, measurement, and proposed pathways linking chronotype to mental health. Recent Findings Eveningness continues to show the strongest and most consistent associations with depressive disorders, including major depressive disorder and seasonal affective disorder. Supporting evidence linking eveningness to bipolar disorder, suicidality, and addictive behaviors has expanded, based on several longitudinal cohort studies. Findings for anxiety disorders, post-traumatic stress disorder, obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, autism spectrum disorder, personality disorders, and psychotic disorders remain more mixed, partly reflecting heterogeneity in samples and chronotype definitions. A small but increasing number of studies incorporate objective markers (e.g., actigraphy, dim-light melatonin onset) and intensive designs (e.g., ecological momentary assessment), allowing for more precise estimates of sleep–wake timing. However, these multimethod approaches remain limited, and findings across modalities are inconsistent. Summary Chronotype is robustly associated with multiple psychiatric outcomes, most notably depression, substance use, and aspects of bipolar disorder and suicidality. Despite more longitudinal and multimethod evidence, the literature remains dominated by cross-sectional designs and subjective measures that may conflate biological phase with behavioral or contextual factors. Future work should integrate behavioral, biological, and environmental data across time to determine whether chronotype reflects a causal influence, a vulnerability marker, or an epiphenomenon of psychopathology.