Evaluation of the NICE mini-GRACE Risk Scores for Acute Myocardial Infarction Using the Myocardial Ischaemia National Audit Project (MINAP) 2003-2009: National Institute for Cardiovascular Outcomes Research (NICOR)

Heart. 2013 Jan;99(1):35-40. doi: 10.1136/heartjnl-2012-302632. Epub 2012 Sep 22.

Abstract

Objective: To evaluate the performance of the National Institute for Health and Clinical Excellence (NICE) mini-Global Registry of Acute Coronary Events (GRACE) (MG) and adjusted mini-GRACE (AMG) risk scores.

Design: Retrospective observational study.

Setting: 215 acute hospitals in England and Wales.

Patients: 137 084 patients discharged from hospital with a diagnosis of acute myocardial infarction (AMI) between 2003 and 2009, as recorded in the Myocardial Ischaemia National Audit Project (MINAP).

Main outcome measures: Model performance indices of calibration accuracy, discriminative and explanatory performance, including net reclassification index (NRI) and integrated discrimination improvement.

Results: Of 495 263 index patients hospitalised with AMI, there were 53 196 ST elevation myocardial infarction and 83 888 non-ST elevation myocardial infarction (NSTEMI) (27.7%) cases with complete data for all AMG variables. For AMI, AMG calibration was better than MG calibration (Hosmer-Lemeshow goodness of fit test: p=0.33 vs p<0.05). MG and AMG predictive accuracy and discriminative ability were good (Brier score: 0.10 vs 0.09; C statistic: 0.82 and 0.84, respectively). The NRI of AMG over MG was 8.1% (p<0.05). Model performance was reduced in patients with NSTEMI, chronic heart failure, chronic renal failure and in patients aged ≥85 years.

Conclusions: The AMG and MG risk scores, utilised by NICE, demonstrated good performance across a range of indices using MINAP data, but performed less well in higher risk subgroups. Although indices were better for AMG, its application may be constrained by missing predictors.

Publication types

  • Comparative Study
  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Academies and Institutes*
  • Aged
  • England / epidemiology
  • Female
  • Humans
  • Male
  • Medical Audit
  • Myocardial Infarction / classification
  • Myocardial Infarction / diagnosis*
  • Myocardial Infarction / mortality
  • Outcome Assessment, Health Care / methods*
  • Prognosis
  • Registries
  • Reproducibility of Results
  • Retrospective Studies
  • Risk Assessment*
  • Risk Factors
  • Severity of Illness Index
  • Survival Rate
  • Time Factors
  • Wales / epidemiology