Validity of the GRACE score for 6-month death or reinfarction after presentation with acute myocardial infarction in patients 80 years of age and older.

INTRODUCTION AND OBJECTIVE

The Global Registry of Acute Coronary Events (GRACE) risk score provides a prediction of the probability of death and myocardial infarction within 6 months after acute coronary syndrome. Our aim was to detect the validity of the GRACE risk score in predicting 6-month death or reinfarction in Chinese acute myocardial infarction (AMI) inpatients 80 years of age and older between 2003 and 2012.

METHODS

Using the GRACE risk score to predict the combined endpoints of all-cause death or reinfarction within 6 months of AMI, we evaluated its discrimination and calibration by the C-statistic and the Hosmer-Lemeshow test, respectively.

RESULTS

In total, 370 patients presenting with ST segment elevation myocardial infarction (STEMI) and non-STEMI were included. The GRACE risk score ranged between 181 and 325; death or reinfarction within 6 months of AMI was 49.2%. The GRACE model showed good discrimination overall (C-statistic 0.708, 95% confidence interval: 0.655-0.760, P<0.001) and in patients with non-STEMI (C-statistic 0.756, 95% confidence interval: 0.690-0.823, P<0.001). However, the discriminatory capacity was lower in patients with STEMI (C-statistic 0.645, P=0.001). The calibration was optimal overall (Hosmer-Lemeshow, P=0.398) and in the subgroups (STEMI, P=0.098; non-STEMI, P=0.822). There was a high correlation (R=0.926) between the predicted and the observed 6-month death or reinfarction after AMI.

CONCLUSION

The GRACE score is accurate for determination of 6-month death or reinfarction in Chinese AMI inpatients 80 years of age and older; however, the discrimination and calibration performs less well in patients with STEMI.