Effect of Mean Uric Acid on Chronic Kidney Disease Incidence

Abstract

Objective: Hyperuricemia is a risk factor for chronic kidney disease (CKD). I examined gender-specific differences in the association between mean uric acid (MUA) and progression to CKD.

Methods: Between 2008 and 2011, 3,166 participants from the Takaoka Health Care Center who did not have diabetes or hypertension, or an eGFR<60mL/min/1.73m², were followed up for an average of 6.7 years. Study participants were divided into four groups according to results of baseline uric acid or follow-up MUA. CKD was defined as an eGFR<60mL/min/1.73m².

Results: In men, patients with MUA < 6mg/mL were used as the baseline group and multivariate adjusted hazard ratios for incident CKD were: 1.34 (95% CI: 0.97–1.84, p=0.07) in patients with MUA ranging from 6 to < 7mg/dL, 1.64 (95% CI: 1.04–2.57, p<0.04) in patients with MUA ranging from 7 to < 8mg/dL, and 2.32 (95% CI: 1.07–5.04, p<0.04) in patients with MUA > 8mg/dL. In women, patients with MUA < 4.5mg/dL were the baseline group and hazard ratios for incident CKD were: 1.22 (95% CI: 0.90–1.65, p=0.19) when MUA ranged from 4.5 to < 5.5mg/dL, 2.18 (95% CI: 1.41–3.38, p<0.001) when MUA ranged from 5.5 to < 6.5mg/dL, and 11.20 (95% CI: 3.81–32.91, p<0.001) when MUA was > 6.5mg/dL.

Conclusions: MUA is a better predictor of CKD compared to baseline uric acid. The risk of CKD was higher when MUA was > 7mg/dL in men and > 5.5mg/dL in women. Hyperuricemia was associated with a higher risk of CKD in women compared to men.