Low-dose versus standard-dose alteplase for intravenous thrombolysis in patients with acute ischemic stroke in Iran: Results from the safe implementation of treatments in stroke registry

Background: Rates of intracranial hemorrhage (ICH) after intravenous thrombolysis (IVT) differ depending on ethnicity, one reason that few Eastern countries have approved a lower dose of alteplase. Data in this regard are scarce in the Middle Eastern region. Methods: The present retrospective study was performed on data extracted from the Safe Implementation of Treatments in Stroke (SITS) registry. Computed tomography (CT) image analysis was based on the SITS-Monitoring Study (SITS-MOST) definition for symptomatic ICH (SICH). Functional outcome at 3 months was assessed using the modified Rankin Scale (mRS). Multivariate logistic regression including adjusted analysis was used for comparison between groups. Results: Of 6615 patients, 1055 were enrolled. A total of 86% (n = 906) received a standard dose and 14% (n = 149) received a low dose of alteplase. Favorable 3-month outcome was achieved in 481 (53%) patients in the standard group and 71 (48%) patients in the low-dose group [adjusted odds ratio (AOR) = 1.24, 95% confidence interval (CI): 0.87-1.75, P = 0.218]. SICH occurred in 14 (1.5%) patients in the standard group and 3 (2%) patients in the low-dose group [odds ratio (OR) = 2.77, 95% CI: 0.36-21.04, P = 0.120]. At 3 months, mortality occurred in 145 (16.0%) patients in the standard group and 29 (19.4%) patients in the low-dose group (OR = 1.22, 95% CI: 0.78-1.91, P = 0.346). Conclusion: Low-dose compared to standard-dose alteplase for patients with acute ischemic stroke (AIS) was not associated with fewer hemorrhagic events and there was no significant difference in the favorable 3-month outcome (mRS: 0-2) or mortality rate.