The impact of serum uric acid reduction on renal function and blood pressure in chronic kidney disease patients with hyperuricemia

BackgroundFebuxostat is tolerable in chronic kidney disease (CKD) patients with hyperuricemia. However, the long-term effect of lowering uric acid with febuxostat on renal function and blood pressure has not been elucidated.MethodsThis was a 2years retrospective observational study. 86 CKD patients with hyperuricemia who continued with allopurinol (allopurinol group, n=30), switched from allopurinol to febuxostat (switched group, n=25), or were newly prescribed febuxostat (febuxostat group, n=31) were included in this study. Serum uric acid, estimated glomerular filtration rate (eGFR), blood pressure, and urinary protein were analyzed. Moreover, the impact of serum uric acid reduction on renal function and blood pressure was assessed.ResultsSerum uric acid in the switched and febuxostat groups was significantly reduced at 6months (switched group; 8.491.32-7.19 +/- 1.14mg/dL, p<0.0001, febuxostat group; 9.43 +/- 1.63-6.31 +/- 0.90mg/dL, p<0.0001). In the allopurinol group, serum uric acid was increased (6.86 +/- 0.87-7.10 +/- 0.85mg/dL, p=0.0213). eGFR was significantly increased (35.2 +/- 12.8-37.3 +/- 13.9mL/min/1.73m(2), p=0.0232), while mean arterial pressure (93.1 +/- 10.8-88.2 +/- 9.5mmHg, p=0.0039) was significantly decreased at 6months in the febuxostat group, resulting in the retention of eGFR for 2years.ConclusionsThe impact of serum uric acid reduction might have beneficial effects on CKD progression and blood pressure. However, a large prospective study is needed to determine the long-term efficacy of febuxostat therapy in CKD patients with hyperuricemia.