Serum uric acid is associated with damage in patients with systemic lupus erythematosus

Abstract

Introduction Serum uric acid levels have been reported as predictors of cardiovascular, pulmonary, neurological and renal morbidity in patients with SLE. However, their role in cumulative global damage in these patients has not yet been determined. Objective To determine whether serum uric acid levels are associated with new damage in patients with SLE. Methods This is a longitudinal study of patients with SLE from the Almenara Lupus Cohort, which began in 2012. At each visit, demographic and clinical characteristics were evaluated, such as activity (Systemic Lupus Erythematosus Disease Activity Index-2K or SLEDAI-2K) and cumulative damage (Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index or SDI). Treatment (glucocorticoids, immunosuppressive drugs and antimalarials) was also recorded. Univariable and multivariable Cox regression models were used to determine the impact of serum uric acid levels on the risk of new damage. Results We evaluated 237 patients, with a mean age (SD) at diagnosis of 35.9 (13.1) years; 220 patients (92.8%) were women, and the duration of the disease was 7.3 (6.6) years. The mean SLEDAI-2K and SDI scores were 5.1 (4.2) and 0.9 (1.3), respectively. Serum uric acid level was 4.5 (1.4) mg/dL. Follow-up time was 3.1 (1.3) years, and 112 (47.3%) patients accrued damage during follow-up. In univariable and multivariable analyses, serum uric acid levels were associated with new damage (HR=1.141 (95% CI 1.016 to 1.282), p=0.026; HR=1.189 (95% CI 1.025 to 1.378), p=0.022, respectively). Conclusion Higher serum uric acid levels are associated with global damage in patients with SLE.