Efficacy and Safety of Stem Cell Therapies for Patients with Stroke: a Systematic Review and Single Arm Meta-Analysis

BACKGROUND AND OBJECTIVES: Stem cell-based therapy is a potential new approach in the treatment of stroke. However, the efficacy and safety of these treatments are not yet fully understood. Therefore, we performed a meta-analysis of available single-arm studies using stem cell-based therapy in patients with stroke. METHODS: We searched MEDLINE, EMBASE, and the Cochrane database for studies of stem cell therapy in patients with stroke from its inception through July 2014. The articles included in the search were restricted to the English language, studies with at least 5 patients, and those using cell-based therapies for treating stroke. RESULTS: Fourteen studies included in the meta-analysis. The pooled mean difference in National Institutes of Health Stroke Scale (NIHSS) scores from baseline to follow-up points was 5.7 points (95%CI: −8.2 to −3.2, I(2)=91.5%) decreased. Also the pooled mean difference in modified Bathel index (BI) score was increased by 31.5 points (95%CI: 35.6∼14.9, I(2)=52.7%) and the pooled incidence rate to achieve on modified Rankin score (mRS)≤2 was 40% (95% CI: 30%∼51%, I(2)=35.4%) at follow-up points. The pooled incidence rates of death, seizure, and infection were 13% (95%CI, 8∼23%), 15% (95%CI, 8∼25%), and 15% (95%CI, 8∼23%), respectively. CONCLUSIONS: The published data suggest that stem cell-based therapy for patients with stroke can be judged as effective based on single arm clinical studies. However, clinical benefits of stem cell therapy for patients with stroke need further investigation and reevaluation to test the clinical efficacy.