title: Efficacy and safety of ticagrelor versus clopidogrel in acute coronary syndrome in Taiwan: A multicenter retrospective pilot study.
abstract: BACKGROUND
  The efficacy and safety of ticagrelor compared with clopidogrel in acute coronary syndrome has not previously been evaluated in an Eastern Asian population, which is recognized to have a different response to P2Y12 antagonists compared with the Caucasian population in real-life situations.
  
  
  METHODS
  A multicenter retrospective pilot study was performed to evaluate 928 consecutive patients with acute coronary syndrome, receiving aspirin and one P2Y12 antagonist (324 ticagrelor or 604 clopidogrel). Using propensity score matching, 448 patients were selected and divided into two equal groups. Kaplan-Meier analysis was used to study patient survival and event-free status using the log-rank test. Independent covariates were identified using univariate in a multivariate Cox proportional hazard model.
  
  
  RESULTS
  In the overall cohort, significant differences were observed for certain variables between the two groups. During the mean 164.3 (±116.4)-day follow-up in the overall cohort, ticagrelor treatment had no significant effect on the primary efficacy endpoint (myocardial infarction, stroke, or vascular death); however, in the matched cohort, ticagrelor showed a lower incidence of primary endpoint (hazard ratio: 0.56; 95% confidence interval: 0.30-1.04; p = 0.07) and stroke (hazard ratio: 0.15; 95% confidence interval: 0.02-1.24; p = 0.08) with marginal statistical significance, and a similar bleeding rate. The protective effect of ticagrelor treatment was consistent for all subgroups. More patients treated with ticagrelor experienced dyspnea (21.0% vs. 11.6%, p = 0.007), and P2Y12 antagonist treatment was consequently discontinued.
  
  
  CONCLUSIONS
  Ticagrelor treatment could provide a marginally favorable effect at the expense of an increased risk of dyspnea in real-life situations. This pilot study provides a scientific basis to call for a larger, suitably powered Phase 4 prospective or observational study in this ethnic population.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Tainan Municipal Hospital, Tainan, Taiwan, ROC.
authors.forename: I-Chih
authors.initials: IC
authors.lastname: Chen
authors.affiliation: Division of Cardiology, Department of Internal Medicine, National Cheng Kung University College of Medicine and Hospital, Tainan, Taiwan, ROC; Institute of Clinical Pharmacy and Pharmaceutical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan, ROC.
authors.forename: Cheng-Han
authors.initials: CH
authors.lastname: Lee
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Tainan Municipal Hospital, Tainan, Taiwan, ROC.
authors.forename: Ching-Chang
authors.initials: CC
authors.lastname: Fang
authors.affiliation: Division of Cardiology, Department of Internal Medicine, National Cheng Kung University College of Medicine and Hospital, Tainan, Taiwan, ROC. Electronic address: chaoth@mail.ncku.edu.tw.
authors.forename: Ting-Hsing
authors.initials: TH
authors.lastname: Chao
authors.affiliation: Institute of Clinical Pharmacy and Pharmaceutical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan, ROC.
authors.forename: Ching-Lan
authors.initials: CL
authors.lastname: Cheng
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Tainan Municipal Hospital, Tainan, Taiwan, ROC.
authors.forename: Yi
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Tainan Municipal Hospital, Tainan, Taiwan, ROC.
authors.forename: Ching-Lung
authors.initials: CL
authors.lastname: Yu
authors.affiliation: Division of Cardiology, Department of Internal Medicine, National Cheng Kung University College of Medicine and Hospital, Tainan, Taiwan, ROC.
authors.forename: Chih-Chan
authors.initials: CC
authors.lastname: Lin
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Tainan Municipal Hospital, Tainan, Taiwan, ROC.
authors.forename: Chun-Yuan
authors.initials: CY
authors.lastname: Lin
authors.affiliation: Division of Cardiology, Department of Internal Medicine, National Cheng Kung University College of Medicine and Hospital, Tainan, Taiwan, ROC.
authors.forename: Yi-Heng
authors.initials: YH
authors.lastname: Li
mesh_terms: D054058:Acute Coronary Syndrome / Q000188:drug therapy* / Q000401:mortality; D000241:Adenosine / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000077144:Clopidogrel; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D016016:Proportional Hazards Models; D058921:Purinergic P2Y Receptor Antagonists / Q000627:therapeutic use*; D012189:Retrospective Studies; D000077486:Ticagrelor; D013988:Ticlopidine / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use
chemical_list: D010975:Platelet Aggregation Inhibitors; D058921:Purinergic P2Y Receptor Antagonists; D000077144:Clopidogrel; D000077486:Ticagrelor; D000241:Adenosine; D013988:Ticlopidine
keywords: acute coronary syndrome; antiplatelet therapy; clopidogrel; outcomes; ticagrelor