Stroke 2017 01 29;48(1):167-173. Epub 2016 Nov 29.
From the Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, China (Y.W.); China National Clinical Research Center for Neurological Diseases, Beijing (Y.W.); Center of Stroke, Beijing Institute for Brain Disorders, China (Y.W.); Beijing Key Laboratory of Translational Medicine for Cerebrovascular Disease, China (Y.W.); National Cerebral and Cardiovascular Center, Suita, Osaka, Japan (K.M.); Department of Medicine and Therapeutics, Chinese University of Hong Kong (K.S.L.W.); Department of Neurology and Stroke Center, Bichat University Hospital and Medical School, Paris, France (P.A.); Department of Neurology, Stanford University Medical Center, Stanford Stroke Center, Palo Alto, CA (G.W.A.); AstraZeneca, Gothenburg, Sweden (H.D., P.H., J.J.); Department of Neurology, University of California, San Francisco (D.E.); Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA (S.R.E.); Stroke Unit, Hospital Vall d'Hebron, Barcelona, Spain (C.A.M.); and Dean's Office, Dell Medical School, University of Texas, Austin (S.C.J.).
Background And Purpose: In the SOCRATES trial (Acute Stroke or Transient Ischemic Attack Treated With Aspirin or Ticagrelor and Patient Outcomes), ticagrelor was not superior to aspirin. Because of differences in patient demographics and stroke disease pattern in Asia, outcomes of ticagrelor versus aspirin were assessed among Asian patients in a prespecified exploratory analysis.
Methods: Baseline demographics, treatment effects, and safety of ticagrelor and aspirin were assessed among Asian patients. Differences in outcomes between groups were assessed using Cox proportional hazard model.
Results: A total of 3858 (29.2%) SOCRATES participants were recruited in Asia. Among the Asian patients, the primary end point event occurred in 186 (9.6%) of the 1933 patients treated with ticagrelor, versus 224 (11.6%) of the 1925 patients treated with aspirin (hazard ratio, 0.81; 95% confidence interval, 0.67-0.99). The exploratory P value for treatment-by-region interaction was 0.27. The primary end point event rate in the Asian subgroup was numerically higher than that in the non-Asian group (10.6% versus 5.7%; nominal P<0.01). Among the Asian patients, the rate of PLATO (Platelet Inhibition and Patient Outcomes)-defined major bleeding was similar in the ticagrelor group and the aspirin group (0.6% versus 0.8%; hazard ratio, 0.76; 95% confidence interval, 0.36-1.61).
Conclusions: The event rates were numerically higher in the Asian patients. Among the Asian patients with acute stroke or transient ischemic attacks, there was a trend toward a lower hazard ratio in reducing risk of the primary end point of stroke, myocardial infarction, or death in the ticagrelor group.
Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01994720.