Outcomes of low-dose versus standard-dose alteplase in acute ischemic stroke patients aged over 80 years: A real-world propensity score-matched study from China

BACKGROUND: Optimal alteplase dosing for intravenous thrombolysis in stroke patients aged >80 years remains debated due to underrepresentation in pivotal trials. This study evaluates the relative effectiveness and safety of low-dose (0.6 mg/kg) versus standard-dose (0.9 mg/kg) alteplase in elderly patients treated within 4.5 hours of onset. METHODS: Utilizing the China Stroke Center Alliance registry database (2018-2022), we conducted a propensity score-matched analysis encompassing 6,522 patients over 80 years of age, ultimately generating 2,050 matched pairs. The primary outcome was functional dependence or death at discharge (mRS 2-6). Secondary measures included major disability (mRS 3-6), in-hospital mortality, and symptomatic intracranial hemorrhage (sICH). RESULTS: The primary outcome showed no statistical difference between low-dose (81.6 %) and standard-dose (81.8 %) groups (OR 0.99; 95 % CI 0.84-1.16; P=0.871). Rates of major disability (56.0 % vs. 57.7 %; OR 1.02; P=0.730), mortality (15.6 % vs. 14.4 %; OR 1.10; P=0.294), and sICH (4.4 % vs. 5.2 %; OR 0.85; P=0.274) were broadly alike. Low-dose alteplase showed a numerical decline in bleeding events. Subgroup analysis found no modifying factors. CONCLUSIONS: In octogenarian stroke patients, low-dose alteplase offers parallel efficacy and safety to standard therapy, with a possible reduction in hemorrhagic complications. These results support low-dose regimens as a reasonable option for elderly patients, particularly when minimizing bleeding risk is a clinical priority.