Association between Serum Uric Acid and the Early Marker of Kidney Function Decline among Chinese Middle-Aged and Older Population: Evidence from the China Health and Retirement Longitudinal Study.

Objective: To evaluate the association between serum uric acid (SUA) and kidney function decline.
Methods: Data was obtained from the China Health and Retirement Longitudinal Study on the Chinese middle-aged and older population for analysis. The kidney function decline was defined as an annual estimated glomerular filtration rate (eGFR) decrease by > 3 mL/min per 1.73 m ² . Multivariable logistic regression was applied to determine the association between SUA and kidney function decline. The shape of the association was investigated by restricted cubic splines.
Results: A total of 7,346 participants were included, of which 1,004 individuals (13.67%) developed kidney function decline during the follow-up of 4 years. A significant dose-response relation was recorded between SUA and the kidney function decline ( OR 1.14, 95% CI 1.03-1.27), as the risk of kidney function decline increased by 14% per 1 mg/dL increase in SUA. In the subgroup analyses, such a relation was only recorded among women ( OR 1.22, 95% CI 1.03-1.45), those aged < 60 years ( OR 1.22, 95% CI 1.05-1.42), and those without hypertension and without diabetes ( OR 1.22, 95% CI 1.06-1.41). Although the dose-response relation was not observed in men, the high level of SUA was related to kidney function decline ( OR 1.83, 95% CI 1.05-3.17). The restricted cubic spline analysis indicated that SUA > 5 mg/dL was associated with a significantly higher risk of kidney function decline.
Conclusion: The SUA level was associated with kidney function decline. An elevation of SUA should therefore be addressed to prevent possible kidney impairment and dysfunction.
(Copyright © 2023 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.)