ObjectiveTo systematically evaluate the association between red cell distribution width (RDW) and prognosis of patients with acute ischemic stroke (AIS) undergoing intravenous thrombolytic therapy.MethodsWe searched the PubMed, Embase, Cochrane Library, Web of Science, Chinese Biomedical Literature Service System, China National Knowledge Infrastructure, Wanfang database, and CQVIP database to identify eligible studies evaluating the relation between RDW and prognosis in AIS patients receiving intravenous thrombolysis from the establishment of databases to May 2021. The Newcastle-Ottawa Scale was used to evaluate the literature quality, and RevMan 5.3 software was used to process the data. The relationship between RDW and prognosis in AIS patients treated with intravenous thrombolytic therapy was analyzed using odds ratio (OR) and 95% confidence interval (CI).ResultsFive studies with a total of 1 269 participants were included into this meta-analysis. All the studies were retrospective case-control studies. Because of statistical heterogeneity (I2=59%, P=0.04), random-effects model was chosen. Meta-analysis result showed that among AIS patients who received intravenous thrombolysis, those with elevated RDW before thrombolysis were more likely to have poor prognosis than those without elevated RDW [OR=1.50, 95%CI (1.14, 1.98), P=0.004].ConclusionElevated RDW is associated with adverse outcome of AIS patients treated with thrombolysis, and may be a risk factor for poor prognosis in patients treated with thrombolytic therapy.