Contributions
Abstract: P807
Type: Poster
Abstract Category: Therapy - symptomatic - 33 Treatment of specific symptoms
Background: Impairment in walking ability is a hallmark feature of Multiple Sclerosis (MS). Fampridine (FAM) has been reported to improve walking ability, as measured by 25 Foot Walk Test (25FWT) time, in MS patients who respond to this therapy. However, the improvement in economy of walking, as measured by expired gas analysis, in responding subjects has not been reported. Accordingly, it is the objective of this study to determine if, and to what extent, walking economy is improved in MS patients who respond to FAM.
Methods: Ethical approval was obtained for this study. Inclusion criteria: Expanded Disability Status Score between 3.5 and 5.5 and responders to FAM therapy (defined as improvement in 25FWT time of 10% or greater). Subjects responding to FAM discontinued their therapy and were scheduled for 3 subsequent treadmill (TM) sessions. TM1 and TM2 were performed between 7 and 14 days after discontinuation of FAM to allow for washout. TM1 familiarized the subject to the treadmill test and metabolic measurement equipment and determined a constant speed the subject could walk at for 6 minutes. TM2 involved connecting the subject to the metabolic measurement system and recording resting data for 4 minutes. Subjects then walked for 6 minutes at the predetermined speed before sitting and resting for 4 minutes. Data for the last three minutes of exercise was averaged and used for analysis. After TM2, subjects resumed FAM therapy. TM3 repeated the protocol performed in TM2 and occurred 3-4 weeks after resuming FAM.
Results: Data are presented as (mean±SD). 59 subjects were recruited, 39 responded to FAM
(27 female) with an average age of 52.3(±9.9) years. Pre and post treadmill tests were compared using Repeated Measures ANOVA. Subjects showed an improvement in relative oxygen consumption (VO2) (Pre: 11.39±2.92 vs. Post: 10.75±3.16 mL/kg/min, P=0.057) with significant improvements observed in: Absolute VO2 (Pre: 0.90±0.35 vs. Post: 0.84±0.35 L/min, P< 0.05), ventilation (Pre: 28.16±10.55 vs. Post: 25.89±10.10 L/min, P< 0.05), carbon dioxide production (Pre: 0.80±0.31 vs. Post: 0.75±0.32 L/min, P< 0.05) and mean exercising heart rate (Pre: 108.6±5.9 vs. Post: 104.9±13.7 bpm, P< .0.05).
Conclusion: Subjects responding to FAM show a significantly lower oxygen requirement and heart rate for walking at a constant speed. Further research into the benefits and mechanisms of these improvements needs to be further investigated.
Disclosure: This study was funded through an investigator-initiated trial grant from Biogen.
K. Riess, no other disclosures
B. Stewart, no other disclosures
Abstract: P807
Type: Poster
Abstract Category: Therapy - symptomatic - 33 Treatment of specific symptoms
Background: Impairment in walking ability is a hallmark feature of Multiple Sclerosis (MS). Fampridine (FAM) has been reported to improve walking ability, as measured by 25 Foot Walk Test (25FWT) time, in MS patients who respond to this therapy. However, the improvement in economy of walking, as measured by expired gas analysis, in responding subjects has not been reported. Accordingly, it is the objective of this study to determine if, and to what extent, walking economy is improved in MS patients who respond to FAM.
Methods: Ethical approval was obtained for this study. Inclusion criteria: Expanded Disability Status Score between 3.5 and 5.5 and responders to FAM therapy (defined as improvement in 25FWT time of 10% or greater). Subjects responding to FAM discontinued their therapy and were scheduled for 3 subsequent treadmill (TM) sessions. TM1 and TM2 were performed between 7 and 14 days after discontinuation of FAM to allow for washout. TM1 familiarized the subject to the treadmill test and metabolic measurement equipment and determined a constant speed the subject could walk at for 6 minutes. TM2 involved connecting the subject to the metabolic measurement system and recording resting data for 4 minutes. Subjects then walked for 6 minutes at the predetermined speed before sitting and resting for 4 minutes. Data for the last three minutes of exercise was averaged and used for analysis. After TM2, subjects resumed FAM therapy. TM3 repeated the protocol performed in TM2 and occurred 3-4 weeks after resuming FAM.
Results: Data are presented as (mean±SD). 59 subjects were recruited, 39 responded to FAM
(27 female) with an average age of 52.3(±9.9) years. Pre and post treadmill tests were compared using Repeated Measures ANOVA. Subjects showed an improvement in relative oxygen consumption (VO2) (Pre: 11.39±2.92 vs. Post: 10.75±3.16 mL/kg/min, P=0.057) with significant improvements observed in: Absolute VO2 (Pre: 0.90±0.35 vs. Post: 0.84±0.35 L/min, P< 0.05), ventilation (Pre: 28.16±10.55 vs. Post: 25.89±10.10 L/min, P< 0.05), carbon dioxide production (Pre: 0.80±0.31 vs. Post: 0.75±0.32 L/min, P< 0.05) and mean exercising heart rate (Pre: 108.6±5.9 vs. Post: 104.9±13.7 bpm, P< .0.05).
Conclusion: Subjects responding to FAM show a significantly lower oxygen requirement and heart rate for walking at a constant speed. Further research into the benefits and mechanisms of these improvements needs to be further investigated.
Disclosure: This study was funded through an investigator-initiated trial grant from Biogen.
K. Riess, no other disclosures
B. Stewart, no other disclosures