Abstract WP68: The Risk of Hemorrhagic Transformation After Thrombolysis for Acute Ischemic Stroke in Chinese vs. North American Patients: A Comparative Study

Abstract

Introduction: There is a widespread belief that Asian population is more susceptible to bleeding, which limits the use of t-PA in patients with ischemic stroke (AIS) in China because of the fear of hemorrhagic transformation (HT). However, this has not been examined in clinical practice. We undertook the current study to compare the incidence of symptomatic HT (SHT) among thrombolysis-treated AIS patients in 2 academic institutions in China and United States. Methods: We compared the clinical and radiological features of 191 consecutive patients treated with IV t-PA within 4.5h of onset ± endovascular therapy from an American (ASC; n = 86) and a Chinese stroke centers (CSC; n = 105). SHT was defined using various definitions based on the NINDS t-PA, ECASS-2, and a modified version of SITS-MOST study (mSITS-MOST) criteria. We used penalized logistic regression to adjust for confounding variables and to identify predictors of SHT. Results: ASC patients were older; had higher prevalence of women; diabetes, hypertension, and cardiac disease; and use of anti-thrombotics and statins. They also had higher baseline serum glucose, shorter onset-to-treatment time, and fewer endovascular interventions. However, none of these emerged as independent predictor of SHT. On logistic regression, there was a trend for an association between baseline serum glucose and the risk of SHT in the ACS population (p=0.056), but not the CSC cohort (p=0.119). The rates of SHT were higher in the ASC cohort compared to the CSC cohort, as follows: 18.6% vs. 13.9% based on NINDS definition of SHT; 15.1% vs. 11.9% based on ECASS-2; and 11.6% vs. 5.0% based on mSITS-MOST. Despite higher rates of SHT in the ASC, fatal HT occurred in only 5.9% of cases vs. 7.9% in CSC cases. However, none of these differences were significant (unadjusted and adjusted p values >0.05). Conclusions: Contrary to perceived notions that HT is more common in AIS Chinese patients, we found that the rate of SHT after t-PA is equivalent between Chinese and North American stroke patients. Our findings require further confirmation in a larger and multi-institutional cohort of patients. Similar results could have a positive impact on increased use of t-PA for AIS in China and other Asian countries.