Dynamic walking features and improved walking performance in multiple sclerosis patients treated with fampridine (4-aminopyridine)

Abstract

BackgroundImpaired walking capacity is a frequent confinement in Multiple Sclerosis (MS). Patients are affected by limitations in coordination, walking speed and the distance they may cover. Also abnormal dynamic walking patterns have been reported, involving continuous deceleration over time. Fampridine (4-aminopyridine), a potassium channel blocker, may improve walking in MS. The objective of the current study was to comprehensively examine dynamic walking characteristics and improved walking capacity in MS patients treated with fampridine.MethodsA sample of N = 35 MS patients (EDSS median: 4) underwent an electronic walking examination prior to (Time 1), and during treatment with fampridine (Time 2). Patients walked back and forth a distance of 25 ft for a maximum period of 6 min (6-minute 25-foot-walk). Besides the total distance covered, average speed on the 25-foot distance and on turns was determined separately for each test minute, at Time 1 and Time 2.ResultsPrior to fampridine administration, 27/35 patients (77 %) were able to complete the entire 6 min of walking, while following the administration, 34/35 patients (97 %) managed to walk for 6 min. In this context, walking distance considerably increased and treatment was associated with faster walking and turning across all six test minutes (range of effect sizes: partial eta squared = .34-.72). Importantly, previously reported deceleration across test minutes was consistently observable at Time 1 and Time 2.DiscussionFampridine administration is associated with improved walking speed and endurance. Regardless of a treatment effect of fampridine, the previously identified, abnormal dynamic walking feature, i.e. the linear decline in walking speed, may represent a robust feature.ConclusionsThe dynamic walking feature might hence be considered as a candidate for a new outcome measure in clinical studies involving interventions other than symptomatic treatment, such as immune-modulating medication.Trial registrationDRKS00009228 (German Clinical Trials Register). Date obtained: 25.08.2015.

Multiple Sclerosis and Clinical Gait Analysis before and after Fampridine: A Systematic Review

“…Certain studies (4 of 17) provided a precise time for this criterion: mean time to do the T25FW was between 8 and 45 s [8,13,15,24]. Only one study required patients to be able to walk for at least 3 min [20].…”

“…The MSFC battery of tests also includes tests to evaluate upper-limb function (the 9 Hole-Peg Test) and cognition (the Paced Auditory Serial Addition Test). Secondary Criteria Other walking tests, such as the 2-Minute Walk Test (2MWT) [19,23,25,27] or the 6-Minute Walk Test (6MWT), were sometimes used in association with the T25FW to evaluate endurance [16,20,28,29]. The most recent studies [17,18,28] also used the 6-Spot Step Test to evaluate coordination and balance while walking.…”

“…When it was taken into account, the score had to be between 4 and 7 inclusive [17][18][19][20][21][22] or between 3.5 and 6.5 [23]. However, for the majority of studies (17 of 18), gait disorders had to be established objectively before treatment by using the timed 25-foot walk (T25FW).…”

“…Concerning prior treatment with fampridine, it was considered an exclusion criterion in 2 of 18 studies. In the other studies, patients could be included provided that a wash-out period had been respected for at least 24 h [20] or, more prudently, for 4 weeks [16].…”

“…The most recent studies [17,18,28] also used the 6-Spot Step Test to evaluate coordination and balance while walking. Of these, 2 studies conducted an analysis of spatiotemporal gait parameters [19,20].…”