P846Discriminatory power of the grace score in non-ST segment elevation myocardial infarction in the real world: results from the portuguese registry on acute coronary syndromes
Authors: Alegria S , Marques A , Pereira A R , Briosa A , Sebaiti D , Gomes A C , Morgado G , Cale R , Martins C , Rangel I , Pereira H 
Published: October 2019

Introduction

Current clinical practice guidelines recommend risk stratification in patients with acute coronary syndrome (ACS) upon admission to the hospital. The Global Registry of Acute Coronary Events (GRACE) risk score was developed in a large multinational registry to predict both mortality and the combined events of death or reinfarction during the hospital stay and 6 months after discharge. Given the substantial regional variation and temporal changes in patient characteristics and management patterns, specially in non-ST segment elevation myocardial infarction (NSTEMI) patients, we sought to validate this risk score in a contemporary Portuguese population.

Purpose

To assess the discriminatory power of the GRACE risk score in a Portuguese contemporary cohort of patients with NSTEMI submitted to invasive strategy, regarding in-hospital mortality and the combined end-point of reinfarction and/or in-hospital mortality.

Methods

We included patients with NSTEMI submitted to coronary angiogram from the Portuguese Registry on Acute Coronary Syndrome (ProACS). For each patient, we calculated the GRACE risk score and classified them in low, intermediate or high risk, according to the cut-offs recommended in the guidelines. The discriminatory capacity of the GRACE risk score was evaluated by the area under the receiver operating characteristic [ROC] curve. The primary endpoint was defined as the occurrence of reinfarction and in-hospital mortality, and the secondary endpoint was in-hospital mortality.

A model with an AUC-ROC between 0.8 and 0.9 was considered to have a good capacity for discrimination.

Results

Among the 19.430 patients included in the ProACS between October 2010 and January 2019, we identified 7304 patients with NSTEMI that performed coronary angiogram and had the GRACE score calculated (37.6%). Patients were divided in three groups according to the GRACE score (group 1: 1–108; group 2: 109–140; group 3: 141–372), with 24.9% included in group 1, 33.0% in group 2, and 42.1% in group 3. Most patients were male (73.4%), with a mean age of 66±12 years, and 48.0% were admitted to non-percutaneous coronary intervention centers. In-hospital mortality was 1.0% and the primary endpoint occurred in 2.2% of the patients. The discriminatory capacity of the GRACE score in our population was good regarding in-hospital mortality: the area under the ROC curve was 0.83 (95% confidence interval [CI], 0.783–0.878), with the best cut-off of 148. The discriminatory capacity for the primary end-point was reasonable; the area under the ROC curve was 0.700 (95% CI 0.654–0.745), and the best cut-off was 164.

Conclusions

In our population of patients with NSTEMI submitted to an invasive strategy, the GRACE risk score presented a moderate discriminatory capacity for the occurrence of reinfarction and in-hospital, and a a good discriminatory power for in-hospital mortality.