Development and validation of a bleeding risk model for patients undergoing elective percutaneous coronary...

Accurate estimation of bleeding risk in patients undergoing elective percutaneous coronary intervention (PCI) is difficult and not based on widely accepted scores or characteristics. We developed and validated a simple prediction model for major bleeding using the SafeTy and Efficacy of Enoxaparin in PCI patients, an internationaL randomized Evaluation (STEEPLE) trial, which demonstrated the superior safety of enoxaparin over unfractionated heparin (UFH) in 3528 patients undergoing elective PCI.

Independent predictors of non-coronary artery bypass graft (CABG)-related major bleeding events were determined using stepwise multivariate logistic regression analysis from a development dataset using bootstrap resampling. These predictors were assigned an integer coefficient (risk score) proportional to the estimated coefficient from the logistic model. Risk scores were tested in a validation cohort. Female sex, use of unfractionated heparin (vs. enoxaparin), and use of a glycoprotein IIb/IIIa inhibitor (vs. nonuse) were the strongest independent predictors of bleeding. Extensive testing found that the final model performed well with bootstrap resampling in the development set (c-statistic 0.75; 95% CI: 0.70-0.82; Hosmer-Lemeshow p = 0.29), validation set (c-statistic 0.67; Hosmer-Lemeshow p = 0.12), and subgroups of high-risk patients analysed from the validation set (c-statistic ≥ 0.67).

Our model for evaluating the risk of non-CABG-related major bleeding in patients undergoing elective PCI identified sex, the type of antithrombin used, and glycoprotein IIb/IIIa inhibitor use as important indicators of bleeding risk, and accurately predicted the incidence of non-CABG-related major bleeding in patients undergoing elective PCI in the STEEPLE trial.