Performance of a Bleeding-risk Score

Abstract & Commentary

By Michael H. Crawford, MD

Source: Abu-Assi E, et al. Evaluating the performance of the can rapid risk stratification of unstable angina patients suppress adverse outcomes with early implementation of the ACC/AHA guidelines (CRUSADE) bleeding score in a contemporary Spanish cohort of patients with non-ST segment elevation acute myocardial infarction. Circulation. 2010;121:2419-2426.

The can rapid-risk stratification of unstable angina Patients Suppress Adverse Outcomes with Early Implementation of the ACC/AHA Guidelines (CRUSADE) is a registry study of acute coronary-syndrome patients. A bleeding risk score was developed for non-ST elevation myocardial infarction (NSTEMI) patients based upon more than 80,000 such patients in the registry. The purpose of this study is to test the bleeding-risk score in a contemporary Spanish cohort of patients with NSTEMI. This is a retrospective study of 782 patients who met inclusion criteria for this analysis of the predictive ability of the CRUSADE bleeding-risk score. Two or more antiplatelet agents were used in 84%, almost all of whom underwent cardiac catheterization. The total incidence of major bleeding was 9.5%, and increased with the risk-score category: very low 1.5%; low 4.3%; moderate 7.8%; high 11.8%; and very high 28.9% (p < 0.001). The score performed well in all treatment subgroups except those treated with two or more antithrombotics who did not undergo cardiac catheterization (n = 48). The authors concluded that the CRUSADE bleeding-risk score was useful in a Spanish cohort of patients with NSTEMI who mainly underwent invasive therapy.

Commentary

In this Spanish cohort of NSTEMI patients, the CRUSADE bleeding-risk score performed well despite several significant differences between the Spanish validation cohort and the CRUSADE derivation population. In addition, the risk of major bleeding was almost identical between the two groups: 9.5 vs. 9.4%. Also, the validation group confirmed the increased mortality risk of having a major bleeding event. Thus, it would seem that using this score could help select the appropriate antithrombic therapy for patients with NSTEMI. For example, in patients with high scores, a drug like prasugrel could be avoided, given its higher bleeding risk vs. clopidogrel. However, most risk scores work better in groups of patients then they often do in individuals. A prospective study randomizing patients to usual care vs. bleeding risk-directed care would be ideal to establish the utility of this score, but will probably never be done.

The major barrier to using this score is its complexity. It involves four categorical characteristics: sex, heart failure on admission, prior vascular event, and presence of diabetes; and four continuous variables: hematocrit, creatinine clearance, heart rate, and systolic blood pressure. The continuous variables are divided into levels with more points for each level. The total possible score is 86. The average score in this study was 30. The eight variables and points assigned to the various levels will not be easy to remember. Thus, electronic access to the scoring system will be necessary for most. Perhaps there is an app for this.