Risk adjustment for in-hospital mortality of contemporary patients with acute myocardial infarction: the acute coronary treatment and intervention outcomes network (ACTION) registry-get with the guidelines (GWTG) acute myocardial infarction mortality model and risk score.

BACKGROUND

accurate risk adjustment is needed to guide quality improvement initiatives and research to improve care of patients with acute myocardial infarction (MI). We developed and validated a model to predict the risk of in-hospital mortality for contemporary patients with acute MI treated in routine clinical practice.

METHODS

the Acute Coronary Treatment and Intervention Outcomes Network (ACTION) Registry-Get With The Guidelines (GWTG) database of patients with acute MI was used to derive (n = 65,668 from 248 US sites) and validate (n = 16,336) a multivariable logistic regression model to predict the likelihood of in-hospital mortality (4.9% in each cohort).

RESULTS

factors with the highest independent significance in terms of mortality prediction included age, baseline serum creatinine, systolic blood pressure, troponin elevation, heart failure and/or cardiogenic shock at presentation, ST-segment changes, heart rate, and prior peripheral arterial disease. The model showed very good discrimination, with c statistics of 0.85 and 0.84 in the derivation and validation cohorts, respectively. The model calibrated well overall and in key patient subgroups including males versus females, age <75 versus ≥ 75 years, diabetes versus no diabetes, and ST-elevation MI versus non-ST-elevation MI. The ACTION Registry-GWTG in-hospital mortality risk score was also developed from the model. Patients with a risk score of ≤ 40 had an observed mortality rate of <4% compared with those with a risk score of 41-50 (12%) and risk scores >50 (34%).

CONCLUSION

the ACTION Registry-GWTG™ in-hospital mortality model and risk score represent simple, accurate risk adjustment tools for contemporary patients with acute MI.