Evaluating the Role of Allopurinol in Mitigating Contrast-Induced Nephropathy in Percutaneous Coronary Intervention Patients: A Systematic Review and Meta-Analysis.

This meta-analysis investigates the potential of allopurinol to prevent contrast-induced nephropathy (CIN), a common and serious complication of percutaneous coronary intervention (PCI). CIN is particularly prevalent among high-risk populations, including patients with chronic kidney disease (CKD) or acute coronary syndrome (ACS), where the administration of contrast agents can exacerbate renal injury. Allopurinol, a xanthine oxidase inhibitor, is known for its dual action in reducing oxidative stress and uric acid production, positioning it as a promising therapeutic candidate to mitigate CIN. The analysis included eight studies encompassing a total of 929 patients undergoing PCI, with a mean age of 63 years. These studies compared the effects of allopurinol with placebo across varying doses and contrast agent types. The results demonstrated a significant reduction in CIN incidence with allopurinol, yielding a pooled odds ratio (OR) of 0.26 [95% CI (0.12, 0.56), P = 0.0006]. Despite the encouraging findings, moderate heterogeneity was observed (I² = 59%), likely arising from variations in study design, patient demographics, and the types of contrast agents used. Sensitivity analysis focusing on studies employing the contrast agent Omnipaque provided further support for the efficacy of allopurinol, with pronounced benefits observed in patients with CKD or ACS. These findings underline the potential of allopurinol as a preventive measure against CIN, especially in high-risk populations. However, the identified heterogeneity and inherent limitations of the included studies highlight the critical need for larger, well-designed randomized controlled trials to confirm these results, establish optimal dosing protocols, and explore the broader applicability of allopurinol in clinical practice.