Your legs are made for walking. Lose leg function and it correlates with the impact of MS on your life in general. #MSBlog #MSResearch
"Who thought you could relate the social and occupational impact of MS to mobility as determined by the number of steps you take in a single day? So called real-life anchors (unemployment, divorce, assistive device use) resulted in a mean minimal clinically important difference MCID of 2,580 steps/day, which was only 45% of mean score for MS group as a whole. Put in another way MSers who were unemployed, divorced or needed a assistive device took 55% fewer steps on average than the whole MS group. Are you surprised? The question that this study raises is whether or not the regulators will accept steps per day as a surrogate, or indicator, for the impact that MS has on the life of someone with the disease?"
BACKGROUND: The number of steps taken per day (steps/day) provides a reliable and valid outcome of free-living walking behavior in MSers.
OBJECTIVE: This study examined the clinical meaningfulness of steps/day using the minimal clinically important difference (MCID) value across stages representing the developing impact of MS.
METHODS: This study was a secondary analysis of de-identified data from 15 investigations totalling 786 MSers and 157 healthy controls. All participants provided demographic information and wore an accelerometer or pedometer during the waking hours of a 7-day period. Those with MS further provided real-life, health, and clinical information and completed the Multiple Sclerosis Walking Scale-12 (MSWS-12) and Patient Determined Disease Steps (PDDS) scale. MCID estimates were based on regression analyses and analysis of variance for between group differences.
RESULTS: The mean MCID from self-report scales that capture subtle changes in ambulation (1-point change in PDSS scores and 10-point change in MSWS-12 scores) was 779 steps/day (14% of mean score for MS sample); the mean MCID for clinical/health outcomes (MS type, duration, weight status) was 1,455 steps/day (26% of mean score for MS sample); real-life anchors (unemployment, divorce, assistive device use) resulted in a mean MCID of 2,580 steps/day (45% of mean score for MS sample); and the MCID for the cumulative impact of MS (MS vs. control) was 2,747 steps/day (48% of mean score for MS sample).
CONCLUSION: The change in motion sensor output of ∼800 steps/day appears to represent a lower-bound estimate of clinically meaningful change in free-living walking behavior in interventions of MS.