Abstract Circadian syndrome (CircS) involves the integration of systemic circadian disruption with cardiometabolic risk factors, but its longitudinal effect on incident chronic lung disease (CLD) remains unknown. This prospective dual-cohort study analyzed data from the China Health and Retirement Longitudinal Study (CHARLS, n = 7,553) and the English Longitudinal Study of Ageing (ELSA, n = 4,957). CircS was defined by the clustering of at least 4 out of 7 circadian-metabolic components. Multivariate Cox proportional hazards models estimated hazard ratios (HRs) for incident CLD over a seven-year follow-up. In the discovery cohort (CHARLS), CircS was independently associated with an increased risk of incident CLD ( HR = 1.16, 95% CI = 1.01–1.33). This was robustly confirmed in the validation cohort (ELSA) with a stronger effect size ( HR = 1.53, 95% CI = 1.20–1.95). Furthermore, subgroup analyses revealed that this risk was significantly amplified by alcohol consumption in the British population ( P < 0.05), suggesting an interactive effect between circadian misalignment and lifestyle stressors. In conclusion, CircS serves as a robust, independent predictor of respiratory decline. Evaluating circadian integrity offers a reliable indicator of respiratory vulnerability, and holistic chronomedicine approaches targeting sleep hygiene and moderate alcohol consumption may help mitigate the global CLD burden.
Liu et al. (2026) studied this question.