1596. Impact of Injury Duration to Start Regenerative Treatment in Chronic Spinal Cord Injury: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Authors: Mohamad Bydon, MD, FAANS ; F M Moinuddin, PhD; Mohammed Ali Alvi, MBBS; Yagiz U Yolcu; Waseem Wahood (Rochester, MN)

Introduction: Regenerative therapy for Spinal cord injury (SCI) is promising field in chronic stage where neurological deficit remains static. Currently, number of clinical trials are performed to investigate regenerative therapy for improving outcomes of patients with chronic SCI. However, in enrollment process, there are different views on how time period between the injury and interventions should be determined. Herein, we sought to evaluate the impact of time-to-intervention in obtaining significant neurologic improvement. Methods: A comprehensive search of PubMed, Ovid MEDLINE and Ovid EMBASE databases was conducted for clinical trials. Studies of regenerative intervention for chronic SCI, which presented individual patient data were included in the final analysis. All patients were divided into three groups based on their time intervals between injury and treatment (group1=<12, group2= 12-23 and group3= ≥24 months). Comparison of different time groups with regards to ASIA Score improvements were conducted. A stratified analysis is also made for separate injury groups according to ASIA Impairment Scale. Results: Eight studies and 142 patients (group1=30, group2=55 and group3=57) were included in this meta-analysis. For patients with a baseline of ASIA Impairment Scale (AIS) A, group2 showed a greater improvement in the cumulative motor and sensory ASIA score than group3 (Estimate:20.4, p=0.047). As for those with a baseline of AIS B, group1 showed a greater improvement in total ASIA score than group2(Estimate: 42.3, p=0.04). Conclusion: The analysis revealed that difference in improvement was more pronounced in patients with complete injuries (AIS A) when treated within 12 to 24 months beyond injury compared to treatment initiation after 24 months. Although this is a long time period and majority of patients are already receiving treatments, the current results suggest that there is still a high chance of significant improvement with timely interventions.