Authors: Fernando Pérez Ruiz, Pascal Richette, Austin G Stack, Ravichandra Karra Gurunath, Ma Jesus García de Yébenes Loreto Carmona
Objective: To determine the impact of achieving serum uric acid (sUA) of <0.36 mmol/L on overall and cardiovascular (CV) mortality in patients with gout. Methods Prospective cohort of patients with gout recruited from 1992 to 2017. Exposure was defined as the average sUA recorded during the first year of followup, dichotomised as ≤ or >0.36 mmol/L. Bi-variate and multivariate Cox proportional hazards models were used to determine mortality risks, expressed HRs and 95% CIs.
Results: Of 1193 patients, 92% were men with a mean age of 60 years, 6.8 years’ disease duration, an average of three to four flares in the previous year, a mean sUA of 9.1 mg/dL at baseline and a mean follow-up 48 months; and 158 died. Crude mortality rates were significantly higher for an sUA of ≥0.36 mmol/L, 80.9 per 1000 patient-years (95% CI 59.4 to 110.3), than for an sUA of <0.36 mmol/L, 25.7 per 1000 patient-years (95% CI 21.3 to 30.9). After adjustment for age, sex, CV risk factors, previous CV events, observation period and baseline sUA concentration, an sUA of ≥0.36 mmol/L was associated with elevated overall mortality (HR=2.33, 95% CI 1.60 to 3.41) and CV mortality (HR=2.05, 95% CI 1.21 to 3.45).
Conclusions: Failure to reach a target sUA level of 0.36 mmol/L in patients with hyperuricaemia of gout is an independent predictor of overall and CV-related mortality. Targeting sUA levels of <0.36 mmol/L should be a principal goal in these high-risk patients in order to reduce CV events and to extend patient survival.
Pérez Ruiz F, Richette P,Stack AG, et al. Failure to reach uric acid target of <0.36 mmol/L in hyperuricaemia of gout is associated with elevated total and cardiovascular mortality. RMD Open 2019;5:e001015. doi:10.1136/ rmdopen-2019-001015.