Efficacy and safety of intravenous thrombolysis in mild ischemic stroke

Background: Intravenous thrombolysis is the preferred clinical treatment for ultra-early (<4.5 h) ischemic stroke. However, whether intravenous thrombolysis should be used in patients with mild stroke remains controversial. This study reports a systematic review and meta-analysis of the efficacy and safety of intravenous thrombolysis in acute mild stroke. Methods: The PubMed, Cochrane Library, MEDLINE, Embase and CBM disc databases were searched for studies on intravenous thrombolysis versus nonthrombolysis in acute mild stroke. All studies published in English prior to March 2022 were retrieved. The studies were screened and selected based on the inclusion and exclusion criteria. Then, the data were extracted and recorded by trained researchers. RevMan 5.4 statistical software was used to analyze the data on the efficacy (mRS score, stroke recurrence rate and mortality at 90 days) and safety (intracranial hemorrhage, symptomatic intracranial hemorrhage) of the patients with acute mild stroke in the intravenous thrombolysis and nonthrombolysis groups. Results: A total of 14 high-quality studies containing 86,063 patients with acute mild stroke (8,824 in the intravenous thrombolysis group; 77,239 in the nonthrombolysis group) were included in this meta-analysis. The meta-analysis results were as follows: (1) Efficacy: There were significant differences in mRS scores of 0~1 and 0~2 between the intravenous thrombolysis and nonthrombolysis groups (mRS 0-1, OR= 1.53, 95% CI: 1.31~1.79, Z=5.40, P <0.00001; mRS 0-2, OR= 1.33, 95% CI: 1.07~1.65, Z=2.59, P =0.01). (2) Safety: There was no significant difference in the recurrence rate of stroke or mortality between the two groups ( recurrence rate, OR= 0.62, 95% CI: 0.35~1.08, Z=1.68, P =0.09; mortality, OR=0.89, 95% CI: 0.45~1.77, Z=0.33, P =0.74). There were more patients with intracranial hemorrhage in intravenous thrombolysis group than in nonthrombolysis group (asymptomatic intracranial hemorrhage, OR= 2.39, 95% CI:1.19~4.80, Z=2.45, P =0.01; symptomatic intracranial hemorrhage, OR= 7.65, 95% CI:3.07~19.05, Z=4.37, P <0.0001). Conclusion: Intravenous thrombolysis significantly improved the functional outcomes but did not reduce mortality at 90 days in patients with acute mild stroke and had a higher risk of intracranial hemorrhage.