Comparison of GRACE and TIMI risk scores in the prediction of in-hospital and long-term outcomes among East Asian non-ST-elevation myocardial infarction patients

Abstract Background Risk stratification in non-ST segment elevation myocardial infarction (NSTEMI) determines the intervention time. Limited study compared two risk scores, the Thrombolysis in Myocardial Infarction (TIMI) and Global Registry of Acute Coronary Events (GRACE) risk scores in the current East Asian NSTEMI patients. Methods This retrospective observational study consecutively collected patients in a large academic hospital between 01/01 and 11/01/2017 and followed for 4 years. Patients were scored by TIMI and GRACE scores on hospital admission. In-hospital endpoints were defined as the in-hospital composite event, including mortality, re-infarction, heart failure, stroke, cardiac shock, or resuscitation. Long-term outcomes were all-cause mortality and cardiac mortality in 4-year follow-up. Results A total of 232 patients were included (female 29.7%, median age 67 years), with a median follow-up of 3.7 years. GRACE score grouped most patients (45.7%) into high risk, while TIMI grouped the majority (61.2%) into medium risk. Further subgrouping the TIMI medium group showed that half (53.5%) of the TIMI medium risk population was GRACE high risk (≥ 140). Compared to TIMI medium group + GRACE < 140 subgroup, the TIMI medium + GRACE high-risk (≥ 140) subgroup had a significantly higher in-hospital events (39.5% vs. 9.1%, p < 0.05), long-term all-cause mortality (22.2% vs. 0% p < 0.001) and cardiac death (11.1% vs. 0% p = 0.045) in 4-year follow-up. GRACE risk scores showed a better predictive ability than TIMI risk scores both for in-hospital and long-term outcomes. (AUC of GRACE vs. TIMI, In-hospital: 0.82 vs. 0.62; long-term mortality: 0.89 vs. 0.68; long-term cardiac mortality: 0.91 vs. 0.67, all p < 0.05). Combined use of the two risk scores reserved both the convenience of scoring and the predictive accuracy. Conclusion GRACE showed better predictive accuracy than TIMI in East Asian NSTEMI patients in both in-hospital and long-term outcomes. The sequential use of TIMI and GRACE scores provide an easy and promising discriminative tool in predicting outcomes in NSTEMI East Asian patients.