The time-averaged serum uric acid can better predict the prognosis of IgA nephropathy.

Background and aim: To understand the clinical and pathological characteristics of patients with IgA nephropathy (IgAN) complicated by hyperuricemia, and to analyze the time-averaged SUA (TA-SUA) on the prognosis of IgAN.

Methods and results: A retrospective analysis of 718 IgAN patients with diagnosis confirmed by renal biopsy and follow-up of more than 1 year was performed. At least two serum uric acid (SUA) levels were measured at intervals of 0.5-1 year during follow-up. The TA-SUA was calculated according to the area under the curve during the follow-up period. The primary endpoint of the study was the doubling of creatinine or end-stage renal disease. Four groups (Q1-Q4) were divided according to TA-SUA quartile spacing from low to high, and the association of the TA-SUA with prognosis in IgAN patients was assessed using Kaplan-Meier survival analysis and Cox proportional hazards models. This study included 718 patients with IgAN, of whom 181 (25.21 %) had hyperuricemia.Compared with the other three groups, the clinical and pathological characteristics of patients in the fourth quarter were more severe in both baseline SUA and TA-SUA groups. Multivariate results suggested that baseline SUA was not an independent risk factor for renal prognosis in IgAN patients after adjustment for clinical variables such as eGFR. High TA-SUA is an independent risk factor for renal prognosis in IgAN patients.

Conclusions: Hyperuricemia is common in IgA nephropathy.High TA-SUA in IgAN patients show more severe clinical features and pathological damage. TA-SUA is an independent risk factor for renal prognosis in IgA nephropathy patients.