Postthrombolysis outcomes in acute ischemic stroke patients of Asian race-ethnicity

Background: Race-ethnic differences may influence postthrombolysis outcomes in acute ischemic stroke patients. Guidelines for thrombolytic therapy to treat Asian stroke patients are based mostly on extrapolated western data. Aims: We undertook to examine outcomes among Asians by comparing a propensity-matched cohort of thrombolyzed patients from a tertiary center in Singapore with nonthrombolyzed Asian comparators collated from Virtual International Stroke Trials Archives (control). Methods: We identified propensity scores-matched patients between thrombolyzed and control Asian patients lodged in the Virtual International Stroke Trials Archives by employing propensity scores method. We compared matched patients for their distributions of three-month functional (modified Rankin scores) and neurological outcomes (National Institute of Health Stroke Scale) by employing Cochran-Mantel-Haenszel test and proportional odds logistic regression analysis. We report odds ratio and 95% confidence interval for improved outcomes on day 90. Results: Virtual International Stroke Trials Archives and National University Hospital, Singapore, contributed 517 and 133 patients of Asian race-ethnicity (n=650), respectively. After propensity matching, sample size reduced to 237 patients; 104 were from Virtual International Stroke Trials Archives. Age (59·7 vs. 61·5 years, P=0·2) and mean baseline National Institute of Health Stroke Scale scores were similar (14) between thrombolyzed and control. The odds ratio for shift toward improved modified Rankin scores and National Institute of Health Stroke Scale distributions after tissue plasminogen activator therapy were 2·8 (95% confidence interval 1·8-4·5, P<0·0001, n=233; Cochran-Mantel-Haenszel P<0·0001) and 2·8 (95% confidence interval 1·7-4·7, P=0·0008, n=201; Cochran-Mantel-Haenszel P=0·0001). Conclusions: Our data indicate that Asian patients derive benefit from thrombolytic therapy.