Effects of acupuncture on ischemic stroke: A systematic review with meta-analyses and trial sequential analyses

Background: Although acupuncture is widely used to treat ischemic stroke, its effects remain uncertain. This systematic review aims to synthesize current evidence on the effects of acupuncture for ischemic stroke and assess whether current randomized controlled trials (RCTs) have sufficient power to detect its effects. Methods: Seven databases and two registry platforms were searched systematically from inception to June 13, 2023, to identify RCTs comparing the effects of acupuncture on ischemic stroke with control groups (placebo/ blank). The Cochrane Risk of Bias 2 (RoB 2) tool was used to evaluate the risk of bias in the included trials. Random effects models through restricted maximum likelihood estimation were further used to estimate the pooled mean differences (MDs) and the corresponding 95 % confidence intervals (CIs). The primary outcome was neurological function (National Institutes of Health Stroke Scale, NIHSS), while secondary outcomes included global disability (modified Rankin Scale, mRS) and activities of daily living (ADLs) (Barthel Index, BI or Modified Barthel Index, MBI). The Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) system was used to evaluate the certainty of the evidence. Trial sequential analysis (TSA) was further applied to control random errors and calculate the required information size (RIS). Results: Forty RCTs involving 4485 patients were included. Acupuncture was found to significantly improve NIHSS (18 trials, 2658 patients; MD =-1.61, 95 % CI [-2.12,-1.09], low certainty evidence), mRS (3 trials, 298 patients; MD =-0.34, 95 % CI [-0.50,-0.19], moderate certainty evidence), and BI/MBI (26 trials, 2562 patients; MD = 8.98, 95 % CI [6.18, 11.77], low certainty evidence). Further, graphs of TSA indicated that the sample size of the trials was sufficient, and the results are robust. Conclusion: Current evidence suggests that acupuncture can significantly improve neurological function, global disability, and ADLs in patients with ischemic stroke. The results were robust, as confirmed by TSA. However, the certainty of the evidence is moderate to low and should be further verified by more high-quality RCTs.