Abstract: Objective To observe the clinical outcome of intravenous thrombolysis for acute ischemic stroke in the patients aged 90 years old and over, and to evaluate the efficacy and safety of intravenous thrombolysis in this population. Methods The clinical data of the patients with acute ischemic stroke aged ≥90 years admitted to Shanghai Jiading District Central Hospital from December 2018 to December 2023 were retrospectively collected. The patients who visited the hospital within 4.5 hours of symptom onset, with a National Institutes of Health Stroke Scale (NIHSS) score >3 on admission, and a pre-stroke modified Rankin Scale (mRS) score ≤3 were enrolled. The clinical outcome of the patients were recorded, including outcome 90 d after onset, in-hospital mortality, the incidence of hemorrhagic transformation, symptomatic intracranial hemorrhage and pulmonary infection. The clinical data were compared between thrombolysis group and non-thrombolysis group. Results A total of 52 patients with a median age of 91 years were enrolled. Among them, there were 37 females (71.2%) and 15 males (28.8%), and the median NIHSS score at onset was 13 (8,20). In this study, 27 patients received intravenous thrombolysis. There were no significant differences in risk factors for stroke, previous history, NIHSS score at onset, pre-stroke mRS score, and TOAST classification between thrombolysis group and non-thrombolysis group. There was significant difference in the proportion of good outcomes between the two groups (33.3% vs 8.0%, P<0.05). There were no significant differences in the incidence rates of hemorrhagic transformation, symptomatic intracranial hemorrhage, pulmonary infection and in-hospital mortality between the two groups. Conclusions Intravenous thrombolysis can increase the proportion of good outcomes in the patients with acute ischemic stroke aged 90 years old and over, and it is safe without increasing the risk of symptomatic intracranial hemorrhage. Therefore, intravenous thrombolysis should not be denied to this population based on age alone.

Key words: nonagenarians, acute ischemic stroke, intravenous thrombolysis, outcome