Circadian-Based Sleep Interventions in Clinical Applications: A Narrative Review

Circadian misalignment, whether from external factors (shift work, jetlag, irregular schedules, or evening screen exposure) or internal factors (chronotype, circadian rhythm disorders), extends beyond sleep disruption to affect immune, cardiovascular, metabolic, and mental health. Despite growing evidence for their efficacy, circadian-based strategies such as timed light exposure, structured activity schedules, meal timing, and circadian psychoeducation, are not consistently integrated into behavioral sleep interventions, and standardized protocols remain limited. While Cognitive Behavioral Therapy for Insomnia (CBT-I) remains standard treatment for insomnia, it does not directly address biological timing. Recent evidence demonstrates that combining CBT-I with circadian rhythm support produces superior outcomes compared to either approach alone. However, gaps remain regarding optimal intervention timing, personalized protocols based on chronotype, long-term efficacy, and implementation in diverse clinical settings. This narrative review synthesizes current evidence on integrating circadian interventions with CBT-I in different clinical applications, and reviews novel assessment tools such as chronotype questionnaires and wearable devices that enable identification of circadian patterns and personalized interventions. By bridging behavioral therapy with circadian-based strategies, clinicians can move beyond symptom management to address underlying causes of sleep disruption, offering a more comprehensive framework for improving sleep and well-being.