The Association between Circadian Syndrome and Frailty in US adults: a cross-sectional study of NHANES Data from 2007 to 2018

Purpose Frailty and Circadian Syndrome (CircS) are prevalent among the elderly, yet the link between them remains underexplored. This study aims to examine the association between CircS and frailty, particularly focusing on the impact of various CircS components on frailty. Materials and methods We conducted a cross-sectional analysis using data from the National Health and Nutrition Examination Survey (NHANES) spanning 2007 to 2018. The 49-item Frailty Index (FI) was employed to assess frailty. To understand the prevalence of CircS in relation to frailty, we applied three multivariate logistic regression models. Additionally, subgroup and interaction analyses were performed to investigate potential modifying factors. Results The study included 8,569 participants. In fully adjusted models, individuals with CircS showed a significantly higher risk of frailty compared to those without CircS (Odds Ratio [OR] = 2.18, 95% Confidence Interval [CI]: 1.91-2.49, p < 0.001). A trend of increasing frailty risk with greater CircS component was observed (trend test p < 0.001). Age (p = 0.01) and race (p = 0.02) interactions notably influenced this association, although the direction of effect was consistent across subgroups. Sensitivity analysis further confirmed the strength of this relationship. Conclusion This study identifies a strong positive correlation between CircS and frailty in the elderly. The risk of frailty escalates with an increasing number of CircS components. These findings highlight the intricate interplay between circadian syndrome and frailty in older adults, offering valuable insights for developing targeted prevention and intervention strategies.