title: The incremental value of troponin biomarkers in risk stratification of acute coronary syndromes: is the relationship multiplicative?
abstract: OBJECTIVE
  To emphasize the importance of troponin in the context of a new score for risk stratifying acute coronary syndromes (ACS) patients. Although troponins have powerful prognostic value, current ACS scores do not fully capitalize this prognostic ability. Here, we weigh troponin status in a multiplicative manner to develop the TRACS score from previously published Rush score risk factors (RRF).
  
  
  METHODS
  2,866 ACS patients (46.7% troponin positive) from 9 centers comprising the TRACS registry, were randomly split into derivation (n=1,422) and validation (n=1,444) cohorts. In the derivation sample, RRF sum was multiplied by 3 if troponins were positive to yield the TRACS score, which was grouped into five categories of 0-2, 3-5, 6-8, 9-11, 12-15 (multiples of 3). Predictive performance of this score to predict hospital death was ascertained in the validation sample.
  
  
  RESULTS
  The TRACS score had ROC AUC of 0.71 in the validation cohort. Logistic regression, Kaplan-Meier analysis, likelihood-ratio and Bayesian Information Criterion (BIC) test indicated that weighing troponin status with 3 in the TRACS score improved the prediction of mortality. Hosmer-Lemeshow test indicated sound model fit.
  
  
  CONCLUSIONS
  We demonstrate that weighing troponin as a multiple of 3 yields robust prognostication of hospital mortality in ACS patients, when used in the context of the TRACS score.
authors: The John H. Stroger Hospital of Cook County (Cook County Hospital), Chicago, Illinois, USA.
authors: Amit P
authors: AP
authors: Amin
authors: Sandeep
authors: S
authors: Nathan
authors: Patricia
authors: P
authors: Vassallo
authors: James E
authors: JE
authors: Calvin