Management of asymptomatic hyperuricaemia in patients with chronic kidney disease by Japanese nephrologists: A questionnaire survey

AIM: Hyperuricaemia is associated with chronic kidney disease (CKD) progression and cardiovascular events (CVE). In a US study, only 4% of rheumatologists initiated urate-lowering therapy in patients with asymptomatic hyperuricaemia (AHU). The present study aimed to clarify how Japanese board-certified nephrologists manage AHU in CKD patients. METHODS: Questionnaires on management of AHU in CKD stage 3 or more were mailed to 1500 Japanese board-certified nephrologists, excluding paediatricians and urologists, randomly selected from the directory of the Japanese Society of Nephrology (n = 2976). RESULTS: Five hundred and ninety-five nephrologists (40%) responded. Most nephrologists (84-89%) recommended that AHU in patients in CKD stages 3-5 should be treated, but fewer nephrologists (63%) recommended that AHU in patients of CKD stage 5D should be treated. The serum urate level to start urate-lowering therapy and the target serum urate level to be achieved (mg/dL) were 8.2 ± 0.9 and 6.9 ± 0.9, 8.4 ± 0.9 and 7.0 ± 1.0, 8.6 ± 1.0 and 7.3 ± 1.1, and 9.1 ± 1.2 and 7.8 ± 1.3 at stages 3, 4, 5 and 5D, respectively. The most frequently used maximal dosage of allopurinol was 100 mg/day at each stage. Benzbromarone was used in 52% of patients at stage 3, but only in 29%, 13% and 5% of patients at stages 4, 5 and 5D, respectively. The most important reasons to treat AHU at CKD stages 3-5 were prevention of CKD progression (45%), CVE (33%), gout (18%) and urolithiasis (3%). CONCLUSION: Most Japanese nephrologists treat AHU in pre-dialysis CKD with an aim to prevent CKD progression or CVE mainly by allopurinol.