Circadian syndrome is associated with the development of chronic kidney disease and rapid decline in kidney function in middle-aged and elder adults: a China nationwide cohort study

The correlation between circadian syndrome (CircS) and kidney outcomes is currently supported by limited empirical evidence. Thus, the objective of this study was to determine the potential relationship between CircS and the development of chronic kidney disease (CKD), as well as the rapid decline in renal function. We utilized data from the 2011 China Health and Retirement Longitudinal Study (CHARLS), which involved 6002 Chinese adults ≥40 years of age. Among these participants, 3670 subsequently had follow-up evaluations in the 2015 survey. The primary outcome was the development of CKD, as defined by an estimated glomerular filtration rates decrease to a level <60 ml/min/1.73 m2, while the secondary outcome was rapid decline in renal function, as defined by an estimated glomerular filtration rates decrease of >5 ml/min/1.73 m2 per year. Multivariable logistic regression analysis was utilized to determine the association between CircS and kidney outcomes. Compared to participants without CircS, those with CircS had a higher risk of CKD in the cross-sectional studies conducted in 2011 (OR, 1.292; 95% CI, 1.053–1.585) and 2015 (OR, 1.860; 95% CI, 1.469–2.355). Participants with CircS in the longitudinal cohort study had a higher risk of progressing to CKD (OR, 3.050; 95% CI, 2.052–4.534) and a rapid decline in renal function (OR, 1.959; 95% CI, 1.433–2.677) after 4 years of follow-up evaluations and adjustment for covariates. Moreover, participants who had CircS with ≥6 CirS components had the highest risk of a rapid decline in renal function (OR, 1.703; 95% CI, 1.054–2.753). CirS significantly increased the risk of CKD progression and rapid decline in renal function among middle-aged and elder individuals. Our study findings highlights the importance of recognizing and managing CirC as a preventative strategy for CKD.