Effect of the Remote Ischemic Postconditioning on the Prognosis of Patients with Acute Ischemic Stroke beyond Time Window: a Randomized Controlled Trial

Background The incidence of acute ischemic stroke (AIS) remains high, and a timely restoration of cerebral blood flow is crucial for its prognosis. There are less therapeutic approaches to promote recovery of cerebral blood flow in AIS patients treated beyond a limited time window. The analysis of remote ischemic postconditioning (RIPostC) on the efficacy, complications and prognosis of AIS patients beyond the time window is of great significance. Objective To investigate the role of RIPostC on the prognosis of AIS beyond time window, thus providing a safe and effective cerebral blood flow restoration way for AIS beyond time window. Methods It was a randomized, parallel group, placebo-controlled trial involving AIS patients beyond time window (onset time > 6 h) of thrombolysis who were hospitalized in the Department of Neurology, Beijing Aerospace General Hospital from September 2, 2021 to August 31, 2022. They were randomly assigned into the control group and experimental group, and treated and followed up for 90 days. General treatment and conventional treatment of cerebrovascular disease were performed in both groups. RIPostC and simulated RIPostC were respectively given 28 times within 14 days in the experimental group and control group, respectively. Before the intervention, and 30 days and 90 days after the intervention, neurological function was assessed using the modified Rankin Scale (mRS) and the National Institutes of Health Stroke Scale (NIHSS). Cognitive function was assessed by the Mini-mental Status Examination (MMSE) and Montreal Cognitive Assessment (MoCA). Daily living ability was assessed by the Instrumental Activity of Daily Living (IADL). Mental status was assessed by the Self-rating Anxiety Scale (SAS) and Self-rating Depression Scale (SDS). Cerebral blood flow velocity was assessed by the transcranial Doppler ultrasound (TCD). Inflammatory response was assessed by measuring interleukin 6 (IL-6) levels. Results Ninety-nine out of 122 AIS patients finally completed the trial and follow-up, including 49 patients in the experimental group and 50 in the control group. There were no significant differences in gender, age, underlying diseases (hypertension, diabetes, coronary heart disease) and baseline NIHSS scores between the two groups (P>0.05). Repeated measures analysis of variance showed that there was an interaction between time and group on MMSE, MoCA, mRS, NIHSS, cerebral blood flow velocity, and IL-6 (P0.05). The incidence of skin ecchymosis [4.00% (2/50) vs. 12.24% (6/49) ] and the overall incidence of adverse events [12.00% (6/50) vs. 34.69% (17/49) ] in the control group were significantly lower than those of the experimental group (P