Association of Increase in Uric Acid Level With Worsening Renal Function in Patients With Congestive Heart Failure

Abstract

Background: Occasionally, increase in serum uric acid (SUA) levels during hospitalization was observed in patients with congestive heart failure (HF), and hyperuricemia is known as an independent predictor of adverse outcomes. In this study, we investigated the factors associated with SUA elevation during hospitalization in HF patients. Methods and Results: We enrolled 98 patients (80 ± 8.8 years, 45 male) hospitalized for congestive HF with normal SUA (<7.0 mg/dL). Blood test was performed on admission (1st measurement) and two weeks later (2nd measurement). Patients were divided into two groups according to the presence of hyperuricemia (SUA > 7.0 mg/dL) at 2nd measurement: high SUA group (n = 28) and normal SUA group (n = 70). No difference was found in the baseline characteristics, such as coronary risk factors, NT-proBNP and renal function between the two groups. However, change in estimated glomerular filtration rate (eGFR) was significantly greater in hyperuricemia group (−8.3 vs −3.8 mL/min/1.73 m2, P = .037). Interestingly, NT-proBNP level was unchangeable between two measurements in high SUA group (5314 to 4540 pg/mL, ns), whereas NT-proBNP was significantly reduced in normal SUA group (2983 to 1966 pg/mL, P = .037). Conclusion: An increase in the SUA levels during hospitalization was associated with worsening renal function. Our study suggested that variation of SUA levels is also important predictor of clinical outcomes in patients with HF.