Development of a New Scoring System to Classify Risk in Unstable Angina

pp 584-590

Abstract

Objective

Unstable angina (UA) is a complex syndrome with diverse outcomes. Although many prognostic variables have been described, few efforts have been made to group them so as to improve their individual power. We performed this study to develop a new scoring system to stratify risk in patients with a diagnosis of UA.

Material and methods

In a first phase, 473 patients were prospectively included to determine which factors were significantly associated with the end-point of refractory angina, acute myocardial infarction(AMI)or death. A risk score scale ranging from 0 to 10 was developed using a multivariate analysis. Such score was validated in a new sample of 242 patients and finally applied to the entire study population (n = 715).

Results

Independent prognostic variables were: ST-segment deviation on the electrocardiogram, age >_ 70 years, previous bypass surgery and troponin T >_0.1 ng/mL. A clear distinction was seen among categories of low, intermediate and high risk, defined according to the risk score. The incidence of the triple end-point was 6%, 19.2% and 44.7% respectively, and the figures for AMI or death were 2%,11.4% and 27.6% respectively (p < 0.00001).

Conclusions

This new scoring system is simple and easy to employ. It allows a very good stratification of risk in patients with UA. They may be divided in three categories, which could be of help for the medical management of this population.