Genetically Elevated Serum Uric Acid and Renal Function in an Apparently Healthy Population

BACKGROUND: The association between uric acid and kidney disease has been extensively investigated. Numerous studies have reported the association between circulating levels of uric acid and renal function. OBJECTIVES: To test, by the Mendelian randomization method, whether there is a causal association between circulating levels of uric acid and renal function. METHODS: In 989 participants, estimated glomerular filtration rate (eGFR) was calculated, the circulating level of uric acid was tested, and the uric acid polymorphism (rs11722228) was genotyped. RESULTS: After adjusting for age, gender, smoking history, alcohol intake, antihypertensive medication, body mass index, waist-to-hip ratio, and levels of urea nitrogen and creatinine, a significant allelic difference was found in uric acid levels for each genotype (p < 0.0001). Furthermore, the circulating levels of uric acid were negatively associated with eGFR after adjusting for cardiovascular risk factors and other potential confounders (p < 0.0001). Meanwhile, eGFR was significantly associated with the genotypes of rs11722228 (β = -0.07; p = 0.02). CONCLUSIONS: Evidence from the Mendelian randomization approach implied a causal relationship between uric acid and renal function in an apparently healthy population.