Serum Uric Acid Levels and Their Association with Renal Function Decline and Kidney Disease Progression in Middle-Aged and Elderly Populations: A Retrospective Cohort Study.

Objective: To evaluate the associations between serum uric acid (SUA) levels and estimated glomerular filtration rate (eGFR) and chronic kidney disease (CKD), with a focus on gender differences, and variations among women pre-and post-menopausal stages. Design: A retrospective cohort study. Setting: A large community-based survey was conducted every two years from 2010 to 2018 in Hangzhou, Zhejiang Province, Southeastern China. Participants: 10,218 participants (40 years or above) without CKD at baseline who underwent three physical examinations were enrolled. CKD was defined as an eGFR of less than 60 mL/min/1.73m Methods: Participants with SUA levels were divided into four groups (Q1-Q4) based on baseline SUA quartiles. The Q1 was the reference. By stratifying participants by gender, the relationships between SUA levels and eGFR were investigated using the generalized additive mixture model. The associations of SUA and the risk of incident CKD were examined using multivariate logistic regression models in the generalized estimating equation. Results: After adjusting for confounding variables, a nonlinear association between SUA and eGFR was observed in females, while an approximately linear relationship was observed in males, suggesting that elevated SUA levels are associated with renal function decline. Furthermore, the highest quartile of SUA was associated with a 2.16-fold (95% CI: 1.31-3.58) increased risk of CKD in males and a 2.76-fold (95% CI: 1.59-4.78) increased risk in females, compared with the lowest quartile. And the spline curves demonstrated a U-shaped pattern, suggesting a potential threshold effect of SUA on the risk of CKD. Additionally, Subgroup analyses revealed significant associations between elevated SUA levels with CKD in postmenopausal women, but not in premenopausal women. Conclusion: Elevated SUA levels are associated with an increased risk of CKD development and renal function decline in middle-aged and elderly individuals, particularly in postmenopausal women.