Association between P2Y12 inhibitor reloading and in-hospital outcomes for patients with non-ST-segment elevation acute coronary syndrome already on chronic P2Y12 receptor inhibitors therapy in China: findings from the CCC–ACS (improving care for cardiovascular disease in China-acute coronary syndrome) project

Abstract Background The association between P2Y12 receptor inhibitors reloading and in-hospital outcomes in non-ST-segment elevation acute coronary syndrome (NSTEACS) patients who were on chronic P2Y12 receptor inhibitors therapy remained underdetermined. Methods The Improving Care for Cardiovascular Disease in China–Acute Coronary Syndrome (CCC–ACS project) is a national registry active from November 2014 to December 2019. 4790 NSTEACS patients on chronic P2Y12 receptor inhibitors therapy were included. Cox proportional hazard models, Kaplan–Meier curves, and subgroup analyses were conducted. Results The NSTEACS patients who received reloading of P2Y12 receptor inhibitors were younger and had fewer comorbid conditions. The reloading group had a lower risk of major adverse cardiac events (MACE) (0.51% vs. 1.43%, P = 0.007), and all-cause death (0.36% vs. 0.99%, P = 0.028), the risks of myocardial infarction and major bleeding were not significantly different between patients with and without reloading. In survival analysis, a lower cumulative risk of MACE could be identified (Log-rank test, P = 0.007) in reloading group. In the unadjusted Cox model, reloading P2Y12 receptor inhibitors was associated with a decreased risk of MACE [HR, 0.35; 95% CI 0.16–0.78; (P = 0.010)] and all-cause death [HR, 0.37; 95% CI 0.14–0.94; (P = 0.036)]. Reloading of P2Y12 receptor inhibitors was associated with a decreased risk of MACE in most of the subgroups. Conclusions In NSTEACS patients already taking P2Y12 receptor inhibitors, we observed a decreased risk of in-hospital MACEs and all-cause mortality and did not observe an increased risk of major bleeding, with reloading. The differential profile in the two groups might influence this association and further studies are warranted. Clinical trial registration: https://www.clinicaltrials.gov (Unique identifier: NCT02306616, date of first registration: 03/12/2014)