Use of Accelerometers to Measure Real-Life Physical Activity in Ambulatory Individuals with Multiple Sclerosis

Abstract

Background: Multiple sclerosis (MS) may negatively affect individuals' participation in physical activity (PA). We used accelerometers to determine PA level in individuals with MS with varying degrees of disability as measured by the Expanded Disability Status Scale (EDSS) during regular daily activities. Methods: Participants wore an accelerometer from 8 a.m. to 9 p.m. for 7 consecutive days. Activity counts recorded during this period were analyzed in 1-minute epochs and categorized into one of four PA levels: light, moderate, hard, and very hard. Results: The study cohort comprised 13 patients with MS and 12 controls. There were significant negative correlations for minutes spent in PA and EDSS measures on weekdays (r = −0.61), weekend (r = −0.64), and full week (r = −0.61) and number of steps taken on weekdays (r = −0.56), weekend (r = −0.80), and full-week average (r = −0.68). Significant positive correlations were found for minutes spent in light PA and EDSS score (r = 0.69). Significant negative correlations were found for minutes spent in moderate and hard PA and EDSS score. No significant difference was seen between the MS group and controls on any parameters (P > .05). Conclusions: This study showed that accelerometers can be used to objectively quantify PA levels in individuals with MS with different disability levels. This cohort demonstrated that the amount of PA is inversely proportional to the degree of physical disability. Collected data revealed not only the amount but also the intensity of PA performed in real-life circumstances.