Creatine kinase and bleeding in patients with acute coronary syndromes

The association between elevated creatine kinase (CK) and bleeding in patients with acute coronary syndrome (ACS) remains incompletely investigated. We undertook this study to assess whether there is an association between elevated CK activity and the risk for bleeding in contemporary patients with ACS.

This post hoc analysis of a randomized trial included 3368 patients with ACS undergoing percutaneous coronary intervention. CK was measured serially in all patients until hospital discharge. The main outcome was 30-day incidence of major bleeding (type 3 to 5 bleeding according to the Bleeding Academic Research Consortium criteria).

Patients were categorized in groups according to the peak CK tertiles: 1st tertile (CK ≤259 U/L; n = 1127 patients), 2nd tertile (CK ≥260 to 990 U/L; n = 1119 patients), and 3rd tertile (CK ≥ 991 U/L; n = 1122 patients). Peak CK activity was higher in patients with bleeding than those without bleeding (771 [316-1845] U/L vs. 496 [190-1357] U/L; P <.001). Bleeding occurred in 26 patients (2.3%) with peak CK within 1st tertile, 39 patients (3.5%) with peak CK within 2nd tertile, and 54 patients (4.8%) with peak CK within 3rd tertile (univariable hazard ratio [HR]=1.39, 95% confidence interval [CI] 1.08 to 1.81, P =.012, per tertile increment in CK values). After adjustment, peak CK activity remained significantly associated with the 30-day bleeding (HR = 1.67 [1.16-2.41]; P =.006 per unit increment in logarithmic CK values). The C statistic of the multivariable model with CK activity was 0.807 [0.770-0.842].

In patients with ACS, peak CK activity was independently associated with increased 30-day incidence of bleeding.