Validation of grace risk score in predicting in-hospital mortality in patients with non ST-elevation myocardial infarction and unstable angina

Objective: To validate the global registry of acute coronary event (grace) risk score in a Pakistani population at Tabba Heart Institute Karachi in patients with non ST-Elevation Myocardial Infarction (NSTEMI) and Unstable Angina (UA). Methods: In this prospective Observational registry study, 530 adults hospitalized patients with a diagnosis of Non-ST-Elevation Myocardial Infarction and unstable angina were enrolled between March 2012 and August 2012 at the Tabba Heart Institute, Karachi, Pakistan. For each patient, the grace risk score was calculated and its discrimination evaluated and correlated with in-hospital mortality using the Kendall's tau-b bivariate correlation test. Each patient was grouped either into high, intermediate or low risk groups according to their GRS. Results: A total of 530 patients with NSTEMI and UA were included; the overall mean grace risk score in our population was 131.87 +/- 41.56. The GRACE Risk Score showed good discrimination, with Area under the ROC curve of 0.803 (95% Cl 0.705-0.902, P < 0.001). During the in-hospital stay, total of 19 (3.6%) patients died, and out of those 15 (8.4%) patients belonged to high risk group. Conclusion: GRACE RS strongly validates the in-hospital mortality among our patient population presenting with a wide spectrum of complications. However, more multicentre registries on a larger population with long term follow up are required to study detailed trends in our population.