Allopurinol and mortality in hyperuricaemic patients.

Abstract

While studies have suggested that gout and hyperuricaemia are associated with the risk of premature death, none has investigated the role of urate-lowering therapy on this critical outcome. We examined the impact of allopurinol, the most commonly used urate-lowering drug, on the risk of mortality in hyperuricaemic patients. From a population of hyperuricaemic veterans of [serum urate level >416 micromol/l (7.0 mg/dl)] at least 40 years of age, we compared the risk of death between incident allopurinol users (n = 2483) and non-users (n = 7441). We estimated the multivariate mortality hazard ratio (HR) of allopurinol use with Cox proportional hazards models. Of the 9924 veterans (males, 98% and mean age 62.7 years), 1021 died during the follow-up. Patients who began treatment with allopurinol had worse prognostic factors for mortality, including higher BMI and comorbidities. After adjusting for baseline urate levels, allopurinol treatment was associated with a lower risk of all-cause mortality (HR 0.78; 95% CI 0.67, 0.91). Further adjustment with other prognostic factors did not appreciably alter this estimate (HR 0.77; 95% CI 0.65, 0.91). The mean change from baseline in serum urate within the allopurinol group was -111 micromol/l (-1.86 mg/dl). Adjusting for baseline urate level, allopurinol users had a 40 micromol/l (0.68 mg/dl) lower follow-up serum urate value than controls (95% CI -0.55, -0.81). Our findings indicate that allopurinol treatment may provide a survival benefit among patients with hyperuricaemia.