Abstract 118: Vagus Nerve Stimulation Paired With Rehabilitation for Post-Stroke Arm Impairment: One Year Follow-Up of the VNS-REHAB Pivotal Trial

Abstract

Background: Persistent post-stroke impairment of the arm and hand is debilitating after stroke. Pairing vagus nerve stimulation (VNS) with upper extremity (UE) rehabilitation improves such deficits after 5 months and was approved by the FDA in 2021. Here, we present 1-year outcomes from the VNS-REHAB pivotal trial. Methods: Stroke participants with moderate-to-severe UE impairment were randomized to task-specific rehabilitation plus either active VNS (n=53, VNS) or sham VNS (n=55, Control). After baseline assessment (Pre-therapy), both groups did 6 wk. of in-clinic therapy followed by a 3-mo. home exercise program combined with active or sham VNS (post90). Controls then crossed over to receive 6 wk. of active VNS followed by a 3-mo. home exercise program (Cross-over post90). Both groups continued active VNS with a home exercise program through 1 year, after which change from Pre-therapy baseline in Fugl-Meyer Assessment-Upper Extremity (FMA-UE) and Wolf Motor Function Test (WMFT) scores were obtained. To determine whether participants made additional gains, 1 year outcome scores (n=70) were also compared to post90 (n=38, VNS) and Cross-over post90 (n=32, Control) scores. Data was available from 74 participants at one year, with others not available mainly due to COVID-19. Results: At 1-year, both FMA-UE and WMFT scores improved from Pre-therapy baseline by 5.3±6.9 (CI=3.7-6.9, p<0.001) and 0.51±0.52 (CI=0.39-0.63, p<0.001) points, respectively. FMA-UE change at 1-year was not significantly different from the post90 (VNS) and Cross-over post90 (control) timepoints (n=70, mean difference: -0.3±4.1, CI=-1.3-0.67, p=0.52), but WMFT was, by an additional 0.09 points (n=70, mean difference: 0.09±0.35, CI=0.01-0.18, p=0.03), indicating that participants either improved or maintained motor gains through 1 year. Conclusion: Improvements in arm and hand function with VNS were maintained at 1-year follow-up, supporting use of VNS paired with rehabilitation as a long-term treatment option for individuals with post-stroke UE impairment. Limitations include sample size and lack of details of therapeutic regimens over the long term. Future studies and an ongoing clinical registry will explore the long-term impact of active VNS in real-world settings.