Contrast-induced nephropathy (CIN) is a major drawback in percutaneous coronary intervention (PCI). Significant uricosuria has been reported following contrast exposure. Allopurinol—a xanthine oxidase inhibitor—has been suggested to prevent the formation of oxygen-free radicals, which may contribute to CIN. The aim of the present study was to evaluate the possible efficacy of allopurinol in preventing CIN.
In this double-blind placebo-controlled trial, patients with an estimated glomerular filtration rate ≥60 mL/min who were admitted for elective PCI, were randomized to receive either allopurinol 600 mg or a placebo administered 24 h before the procedure, and again immediately before the procedure. Blood samples were drawn at 24 h before and 24 h after contrast exposure to measure serum creatinine (SCr), uric acid, and serum cystatin-c.
The baseline characteristics were almost similar between the placebo and allopurinol groups. The overall change in SCr and the rate of CIN, which is defined as ≥25% increase in serum cystatin-c relative to baseline, failed to show a significant difference between the two groups. When adjusted on the baseline cystatin-c, SCr, sex, and positive family history, the difference in the overall increase in serum cystatin-c was statistically significantly lower in the allopurinol group.
Allopurinol administration in patients undergoing PCI failed to show efficacy in preventing CIN. Nevertheless, this effect should be further evaluated in the patient population with chronic kidney disease.