Ambulatory activity in individuals with multiple sclerosis

Specific characteristics of physical activity limitations associated with multiple sclerosis (MS) remain unclear. Our purpose was to examine the impact of MS disability on physical activity behaviors involving ambulation. We also explored relationships among ambulatory activity parameters and clinical measures of gait, balance, and fatigue.

Twenty-one adults with MS participated: 11 without ambulatory limitation (Expanded Disability Status Scale [EDSS] score ≤ 4.5) and 10 with ambulatory limitation (EDSS score > 4.5). Participants wore a step activity monitor for up to 7 days. Daily values were calculated for parameters indicative of (1) overall activity, (2) upper limits of activity output, and (3) activity work-rest cycles. Clinical measures included Multiple Sclerosis Walking Scale, Timed 25-Foot Walk, Timed Up and Go test, 6-Minute Walk, Dynamic Gait Index, Berg Balance Scale, Activities-specific Balance Confidence Scale, and Modified Fatigue Impact Scale. Statistical analyses were conducted using nonparametric tests.

Participants without limitation were more active, demonstrated higher upper limits of activity output, and had longer activity bouts than participants with limitation (P < 0.05). Only 1 participant averaged more than 100 steps per minute over a 30-minute period. Of the ambulatory activity parameters, daily step count was most strongly related to gait and balance measures. Of the clinical measures, EDSS and Multiple Sclerosis Walking Scale scores were most strongly related to daily step count.

Individuals with MS are not necessarily sedentary, but few may achieve recommended daily physical activity levels. Ambulatory activity characteristics revealed new insights into physical activity limitations in MS. The study findings suggest that disability status should direct physical activity interventions.