Effect of Allopurinol on the Treatment of Chronic Kidney Disease: a Systematic Review and Meta-Analysis

Introduction: Chronic kidney disease (CKD) is defined by glomerular filtration rates (GFR) of less than 60 mL/min per 1.73 m2 or albumin to creatinine ratios of greater than 30 mg/g in urine for at least three months. Patients with CKD are at risk of developing the condition, leading to end-stage renal disease (ESRD). On the other hand, hyperuricemia can result in renal failure, increased blood pressure, fibrosis, and the progression of failure. In this study, using the meta-analysis method, we are looking to investigate the effect of allopurinol on the treatment of chronic renal failure. Materials and Methods: In this meta-analysis, which was written based on PRISMA (the Preferred Reporting Items for Systematic Reviews and Meta-Analyses) protocol, International databases including Cochrane, Web of Science, Scopus, PubMed, and Google Scholar search engine were searched. The data were analyzed using STATA (version 14) software, and the significance level of tests was considered P<0.05. Results: In 13 studies with a sample of 1172 people, allopurinol significantly reduced the serum level of uric acid (SMD: -1.28; 95% CI: -1.74, -0.82) more than the control group (SMD: -0.96; 95% CI: -2.09, 0.17). Additionally, allopurinol reduced the systolic blood pressure level by (SMD: -0.32; 95% CI: -0.54, -0.11) mm Hg and it was effective in reducing diastolic blood pressure level by (SMD: -0.39; 95% CI: -0.60, -0.17) mm Hg. However, the difference in scores GFR, proteinuria, cystatin C, before and after allopurinol were not statistically significant. In the control group, the difference in scores before and after the intervention was not significant in any of the above-mentioned cases. Conclusion: In CKD, allopurinol is effective in reducing blood pressure and uric acid levels. However, due to the limited number of studies and the different type of treatment in the control group of the studied studies, it is suggested to conduct more studies in this field. Registration: This study has been compiled based on the PRISMA checklist, and its protocol was registered on the PROSPERO website (ID=CRD42022371439, regional ethical code #IR.IAU. NAJAFABAD.REC.1399.140).