Impact of White Blood Cell Count on Clinical Outcomes in Patients Treated with Aspirin-Free Ticagrelor Monotherapy after Percutaneous Coronary Intervention: Insights from the GLOBAL LEADERS Trial.

AIMS To investigate the efficacy and safety of ticagrelor monotherapy in patients undergoing percutaneous coronary intervention (PCI) stratified according to the baseline white blood cell (WBC) count. METHODS AND RESULTS This is a post-hoc analysis of the GLOBAL LEADERS trial, a multicentre, open-label, randomized all-comer trial in patients undergoing PCI, comparing the experimental strategy (23-month ticagrelor monotherapy following 1-month dual anti-platelet therapy [DAPT]) with the reference strategy (12-month aspirin monotherapy following 12-month DAPT). Patients were stratified into two WBC groups, either < or ≥median WBC count of 7.8 x 109 cells/L (lower or higher WBC group, respectively). The primary endpoint was a composite of all-cause mortality or new Q-wave myocardial infarction (MI) at 2 years.Out of 14,576 patients included in the present study, 7,212 patients (49.5%) were classified as the lower WBC group, who had a significantly lower risk of both ischemic and bleeding outcomes at 2 years. At 2 years, the experimental strategy was associated with a significant lower incidence of the primary endpoint compared with the reference strategy in the lower WBC group (2.8% vs. 4.2%; hazard ratio [HR]: 0.67; 95% CI: 0.52-0.86) but not in the higher WBC group (4.8% vs. 4.7%; HR: 1.01; 95% CI: 0.82-1.25; pinteraction=0.013). There were no significant differences in the risks of BARC type 3 or 5 bleeding between two antiplatelet strategies regardless of the WBC groups. CONCLUSIONS Increased WBC counts, which may reflect degree of inflammation, at the time of index procedure may attenuate the anti-ischemic benefits of ticagrelor monotherapy observed in patients with lower WBC counts.