Effect of Remote Ischemic Conditioning on Heart Rate Responses to Walking in People with Multiple Sclerosis

BACKGROUND: Remote ischemic conditioning (RIC), exposure of body parts to brief periods of circulatory occlusion and reperfusion, has been shown to improve cardiovascular responses to exercise in healthy individuals but its effects in people with MS are unknown. OBJECTIVE: This study aimed to assess the effect of RIC on heart rate responses to walking in people with MS. DESIGN: Double blind randomized controlled trial SETTING: Multiple sclerosis clinic of tertiary care center teaching hospital in the United Kingdom. METHODS: Three cycles of RIC were delivered by occluding the upper arm with a blood pressure cuff inflated to a pressure of 30 mmHg above the systolic blood pressure. In the sham group, the blood pressure cuff was inflated to 30 mmHg below diastolic blood pressure. Heart rate responses to the 6-minute walk test (6MWT), the tolerability of RIC using a numerical rating scale for discomfort (0-10), and adverse events were studied. RESULTS: Seventy-five participants (RIC -38 and Sham-37) completed the study. RIC was well tolerated. Compared to sham, RIC significantly decreased the rise in heart rate (P = 0.04) and percentage of predicted maximum heart rate (P = 0.016) after the 6MWT. CONCLUSION: RIC was well tolerated and improved the heart rate response to walking in people with MS. Further studies on RIC in the management of MS are needed.