Abstract
Background
Chronic kidney disease (CKD) poses a significant global health burden, with oxidative stress implicated in its pathogenesis. The composite dietary antioxidant index (CDAI), integrating multiple dietary antioxidants, may offer a novel approach to CKD risk assessment, yet evidence remains limited.Objective
This study aimed to evaluate the association between CDAI and CKD risk in a nationally representative U.S.Cohort
Materials and methods
Cross-sectional data from 24,202 adults in NHANES (1999 - 2018) were analyzed. CDAI was calculated from six dietary antioxidants (vitamins A/C/E, zinc, selenium, β-carotene). CKD was defined by estimated glomerular filtration rate (eGFR) 2 or UACR ≥ 30 mg/g. Multivariable logistic regression, restricted cubic splines (RCS), and subgroup analyses were employed to assess associations, adjusted for demographics, lifestyle, comorbidities, and laboratory parameters.Results
Participants in the highest CDAI quartile (Q4) had a 27% lower CKD risk (adjusted OR = 0.73, 95% CI: 0.62 - 0.87, p 20. Subgroup analyses showed stronger inverse associations in women, older adults (≥ 65 years), and individuals with diabetes or cardiovascular disease (p-interaction Conclusion
Higher CDAI levels were independently associated with reduced CKD risk, particularly in high-risk subgroups. These findings support the potential role of dietary antioxidants in CKD prevention, warranting further prospective validation.