Efficacy and safety of different doses of intravenous tissue plasminogen activator in Chinese patients with ischemic stroke.

Intravenous tissue plasminogen activator (tPA) at 0.9mg/kg improves outcome in acute ischemic stroke. The dose response to tPA may be different in Chinese patients compared with Western populations, but this has not been systematically examined. We aimed to compare the efficacy and safety of different doses of tPA in Chinese stroke patients. We included all acute ischemic stroke patients treated with tPA within 4.5 hours of onset. Patients were treated with three dose regimens of tPA (0.6-0.7mg/kg, 0.8mg/kg, 0.9mg/kg). The following data were collected: patient demographics; vascular risk factors; neuroimaging results; time of tPA administration; clinical assessment before treatment, at 24 hours and 3months; and modified Rankin Scale (mRS) score at 3months. A total of 105 patients with stroke of Han Chinese origin were included in the study. The baseline characteristics of the three dose groups were well matched. In the 0.9mg/kg group (n=51), 51.1% had favorable outcome at 3months, compared with 38.7% of patients in the 0.8mg/kg group (n=31) (odds ratio [OR] to 0.9mg/kg group, 0.57; 95% CI, 0.19-1.73; p=0.32) and 34.8% in the 0.6-0.7mg/kg group (n=23) (OR to 0.9mg/kg group, 0.31; 95% CI, 0.08-1.16; p=0.08). There were no statistically significant differences in the incidence of symptomatic intracerebral hemorrhage and mortality rate. There was a higher proportion of patients with good functional outcomes in the 0.9mg/kg group. Although not significant, these results strongly support the feasibility and urgent need for a dose ranging trial to establish an optimal tPA dose in Chinese stroke patients.