Serum uric acid and mortality thresholds among men and women in the Irish health system: A cohort study

• Published in: European journal of internal medicine 2021-02, Vol.84, p.46-55
• Main Authors: Browne, Leonard D., Jaouimaa, Fatima-Zahra, Walsh, Cathal, Perez-Ruiz, Fernando, Richette, Paschal, Burke, Kevin, Stack, Austin G.
• Format: Article
• Language: English
• Subjects: Cohort Studies; Female; Humans; Irish adults; Lifetimes; Male; Mortality; Non-linear; Proportional Hazards Models; Retrospective Studies; Risk Factors; Serum uric acid; Uric Acid
• ISSN: 0953-6205; 1879-0828
• DOI: 10.1016/j.ejim.2020.10.001

•SUA exhibits a nonlinear relationship with mortality in Irish patients•Mortality risks of SUA differs between men and women.•Optimal SUA values for best survival in men are 304-454 μmol/l.•Optimal SUA values for best survival in women are < 409 μmol/l.•Substantial reductions in survival are associated with extremes of SUA Elevation of serum uric acid (SUA) is associated with increased mortality; however, controversy exists regarding the nature of the relationship and differences between men and women. We explored relationships of SUA levels with all-cause mortality in a large cohort of patients within the Irish health system. A retrospective cohort study of 26,525 participants was conducted using data from the National Kidney Disease Surveillance System. SUA was modelled in increments of 59.48 µmol/L (1 mg/dL), Cox's proportional hazards model estimated hazard ratios (HRs) and 95% Confidence Intervals (CI), median lifetimes were also computed separately for men and women. Mortality patterns were further explored using penalised splines. There were 1,288 (4.9%) deaths over a median follow-up of 5.1 years. In men, the risk of mortality was greatest for the lowest (535 µmol/L) categories [HR 2.35 (1.65–3.14) and HR 2.52 (1.87–3.29) respectively]; the corresponding median lifetimes for men were reduced by 9.5 and 11.7 years respectively compared to the referent. In women, mortality risks were elevated for SUA >416 mol/L [HR 1.69 (1.13–2.47) and beyond; the corresponding median lifetime for women were reduced by 5.9 years compared to the referent. Spline analysis revealed a U-shaped association between SUA and mortality in men, while for women, the pattern of association was J-shaped. Mortality patterns attributed to SUA differ between men and women. Optimal survival was associated with SUA concentrations of 304–454 µmol/L for men and < 409 µmol/L for women.