Hyperuricemia in addition to GRACE Score improves risk stratification in acute coronary syndromes

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Background Uric acid (UA) is a risk factor for coronary artery disease, and it might be a predictor of outcomes in patients (P) with acute coronary syndromes (ACS). Global Registry of Acute Coronary Events (GRACE) Score is an extensively validated tool for risk stratification in these P. The aim of this study is to evaluate the impact of hyperuricemia (HU) in the prognosis of ACS and compare it with the GRACE Score. Methods This study included all P admitted for ACS between 2007 and 2015 in a Cardiology Department. HU was defined as admission UA levels > 6 mg/dL. In-hospital mortality and all-cause mortality at 12 months after discharge were assessed. Chi-square and Mann-Whitney U tests were used for group comparisons; survival analysis used Kaplan-Meier curves and log-rank tests; and subgroup analysis was performed with an unadjusted Cox model. Results 959 P were included (mean age 67.7±12.8y, 71.1% male). HU occurred in 498 P (51.9%). Its presence was associated with older age (p<0.001); male sex (p=0.034); arterial hypertension (p<0.001); obesity (p=0.006) and chronic kidney disease (p=0.025). At admission, P with HU had higher heart rate (p=0.003); higher Killip-Kimball class (p=0.001); higher plasma concentrations of creatinine (p<0.001), C-reactive protein (p=0.003), blood natriuretic peptide (p=0.010) and triglycerides (p<0.001); and lower high-density lipoprotein cholesterol levels (p<0.001). HU was also associated with conservative treatment of ACS (p=0.005), left main disease (p=0.037) and longer length of hospital stay (p=0.009). Univariate logistic regression analysis showed that HU was a predictor of in-hospital mortality (OR 2.048; 95% CI 1.048-4.005; p=0.036). During the follow-up, P with HU had a significantly decreased survival than P with normal UA levels (Kaplan-Meier x²=8.25; p=0.004). In subgroup analysis, the effect of HU in survival was consistent among P stratified based on gender, age and comorbidities. When P were classified according to serum UA levels and GRACE Score, a progressive decline in survival was found in P without HU and GRACE score≤140, P with HU and GRACE score≤140, P without HU and GRACE score>140, and P with HU and GRACE score>140 (Kaplan-Meier χ²=24.17; p<0.001) - graph 1. Conclusions In this study, HU was associated with in-hospital and 12-month follow-up mortality. Its use may allow a better risk stratification in P with ACS, particularly when combined with the most widely used tool, the GRACE score.