Development and validation of Women Acute Myocardial Infarction in-Hospital Mortality Score (WAMI Score)

Abstract

BackgroundA variety of risk models have been developed to predict acute myocardial infarction (AMI) in-hospital mortality risk. As a distinct, higher-risk population, women with AMI have different risk profiles from their men counterparts. Published researches have indicated that the interaction between variables in these models for in-hospital mortality and gender are significant. Due to the interaction and gender differences, the predicting value of these risk models for women could be controversial. MethodsDatabases from the China Patient-centered Evaluative Assessment of Cardiac Events (China PEACE) Retrospective AMI Study were utilized for model derivation (n=16,100, women were 4896) and databases from the China PEACE Prospective AMI Study for model validation (n=6207, women were 2090). A multivariable backward stepwise logistic regression was used to examine correlates of in-hospital mortality, and the variables were subsequently weighted and integrated into a scoring system. ResultsWe constructed a novel risk-predicting tool to estimate the baseline risk of in-hospital mortality among women with AMI. The risk score includes 8 variables [age, systolic blood pressure, heart rate, initial glomerular filtration rate (GFR), serum glucose, Killip class, cardiac arrest, ventricular tachycardia/ventricular fibrillation (VT/VF)]. The prognostic discriminatory capacity of the Women Acute Myocardial Infarction in-Hospital Mortality (WAMI) risk score was excellent (c statistic 0.84, 95% confidence interval [CI]: 0.83 to 0.86, p<0.001). External validation of the model showed better prognostic capacity (c statistic 0.87, 95% CI: 0.84 to 0.90, p<0.001) than the GRACE risk score (0.77, 95% CI 0.72–0.82, p<0.001) and TIMI risk score (0.72, 95% CI 0.68–0.77, p<0.001). ConclusionsThe WAMI Score is a simple robust tool for predicting the in-hospital mortality risk of women with AMI. Trial registration“China PEACE-Retrospective AMI Study”, NCT01624883, retrospectively registered: April 2012. Date of enrolment of the first participant to the trial: June 17, 2012.“China PEACE-Prospective AMI Study”, NCT01624909, prospectively registered: December 2012. Date of enrolment of the first participant to the trial: June 17, 2012.