Low-dose versus standard-dose recombinant tissue plasminogen activator in the very elderly patients with acute ischaemic stroke: a single-center study in Tianjin, China

Abstract Objective: The optimal dose of recombinant tissue plasminogen activator for acute ischemic stroke among the very elderly patients (aged ≥80 years) in China is unclear. We aimed to assess the efficacy and safety of low-dose (0.6 mg/kg) and standard-dose (0.9 mg/kg) rt-PA for varying severity and age of Chinese geriatric stroke patients. Methods: According to dose of rt-PA, the enrolled patients were divided into two groups: rt-PA low-dose group (0.6 mg/kg) and rt-PA standard-dose group (0.9 mg/kg). The efficacy outcome was favorable functional outcome(modified Rankin Scale score of ≤2) at 90 days. The short-term safety outcomes were intracerebral hemorrhage (ICH), symptomatic intracranial hemorrhage (sICH) and fatal intracerebral hemorrhage (fICH). The long-term safety outcome was death within 90 days. We assessed the efficacy and safety of low-dose vs standard-dose of rt-PA for acute ischemic stroke in Chinese very elderly patients. Results: A total of 201 eligible patients were enrolled; among them, 93 patientswere treated with low-dose rt-PA and 108 patients received standard-dose rt-PA. The incidences of ICH, sICH and fICH in rt-PA low-dose group were lower than rt-PA standard-dose group [8.6%(8/93) vs. 19.4%(21/108), 4.3%(4/93) vs. 10.2%(11/108), 1.1%(1/93) vs. 9.3%(10/108); unadjusted and adjusted P< .05]. There were no statistically significant differences between the two groups concerning the long-term safety index and the effectiveness index. Stratification by stroke severity and age，the favorable functional outcome rate at 90 days of moderate stroke sub-group and ≥90 years old in rt-PA low-dose group were both higher than rt-PA standard-dose group [76.3%(29/38) vs. 52.6%(20/38), 56.5%(13/23) vs. 25.0%(5/20); P< .05] and without a higher risk of mortality (mRS score of 6; P> .05). Conclusions: The efficacy and safety at 90 days of low-dose (0.6 mg/kg) rt-PA intravenous thrombolytic therapy for Chinese geriatric AIS patients was equivalent to the standard-dose (0.9 mg/kg) rt-PA but with a lower risk of ICH, sICH and fICH. For AIS patients with moderate stroke and age 90 years or older, intravenous thrombolytic therapy with rt-PA 0.6 mg/kg is recommended. Confirmation of the results through multicentre, prospective, randomised trial is required.