Hyperuricemia as a risk factor for contrast-induced nephropathy in patients with chronic kidney disease.

Hyperuricemia as a risk factor for contrast-induced nephropathy (CIN) has not been studied. The aim of the present study was to assess the influence of hyperuricemia on the development of CIN in patients undergoing coronary angiography. This was a prospective cohort study. A total of 266 patients with a mean age of 58.33 +/- 7.85 years and serum creatinine > or = 1.2 mg/dl were divided into two groups (hyperuricemic, n = 126, and normouricemic, n = 140). CIN was defined as an increase of > or = 25% in creatinine over baseline within 48 hr of angiography, and hyperuricemia as serum uric acid > or = 7 mg/dl in males and > or = 6.5 mg/dl in females. CIN occurred in 15.1% of the hyperuricemic group and 2.9% of the normouricemic group (P < 0.001). Serum creatinine increased from 1.45 +/- 0.20 to 1.67 +/- 0.45 mg/dl in the hyperuricemic group and from 1.42 +/- 0.16 to 1.56 +/- 0.23 mg/dl in the normouricemic group (P < 0.001). Hyperuricemia [odds ratio (OR) 4.71; 95% confidence interval (95% CI) 1.29-17.21; P = 0.019] and a high incidence of multi-vessel coronary involvement (OR 3.59; 95% CI 1.12-11.48; P = 0.032) in the hyperuricemic group were predictors of CIN. Hypoalbuminemia (P = 0.001) and age > or = 70 years (P = 0.023) were other risk indicators of CIN. Length of hospital stay (P < 0.001) and CIN requiring renal replacement therapy (P = 0.017) were significantly higher in hyperuricemic group. Serum uric acid level > or = 7 mg/dl in males and > or = 5.9 mg/dl in females were found to be the best cut-off value for prediction of CIN. Our data support the hypothesis that patients with hyperuricemia are at risk of developing CIN. 2006 Wiley-Liss, Inc.