Randomized controlled trial of a behavioral intervention targeting symptoms and physical activity in multiple sclerosis.

BACKGROUND: Exercise training is beneficial, but most persons with multiple sclerosis (MS) are sedentary and physically inactive. This has prompted a new focus on the promotion of lifestyle physical activity in MS. We previously designed, tested, and refined a behavioral intervention delivered through the Internet that successfully increased lifestyle physical activity in MS, but have not evaluated the effects on secondary symptomatic and health-related quality of life (HRQOL) outcomes. OBJECTIVE: We conducted a 6-month randomized controlled trial (RCT) that examined the efficacy of an Internet-delivered, behavioral intervention for improving outcomes of fatigue, depression, anxiety, pain, sleep quality, and HRQOL in 82 ambulatory persons with MS. The secondary aim was to replicate previous results regarding change in free-living physical activity. RESULTS: There was a significant and positive effect of the intervention on fatigue severity (p=.001, η ρ (2)=.15) and its physical impact (p=.008, η ρ (2)=.09), depression (p=.006, η ρ (2)=.10), and anxiety (p=.006, η ρ (2)=.10). There were non-significant improvements in pain (p=.08, η ρ (2)=.04), sleep quality (p=.06, η ρ (2)=.05), and physical HRQOL (p=.06, η ρ (2)=.05). We replicated our previous results by demonstrating an increase in self-reported physical activity (p=.001, η ρ (2)=.13). CONCLUSIONS: Our results support behavioral interventions targeting lifestyle physical activity as an alternative approach for managing symptoms in MS.

Psychometric properties of the Fatigue Severity Scale and the Modified Fatigue Impact Scale.

OBJECTIVE: Fatigue is one of the most common, debilitating and life altering symptoms experienced by those with multiple sclerosis (MS) and has become the focus of therapeutic interventions and clinical rehabilitation. There is limited evidence regarding the psychometric properties and clinical relevance of fatigue outcomes for interpreting the effectiveness of intervention and rehabilitation strategies. This study determined the reliability, precision and clinically important change of the uni-dimensional Fatigue Severity Scale (FSS) and the multi-dimensional Modified Fatigue Impact Scale (MFIS). METHODS: The FSS and MFIS along with physical, psychological and cognitive clinical outcomes were administered to a sample of 82 persons with MS in a clinical research setting on two time points, separated by six months. Intraclass correlation coefficient (ICC) analyses established reliability; standard error of measurement (SEM) and coefficient of variation (CV) determined precision; minimal detectable change (MDC) defined clinically important change. RESULTS: Participants varied in type of MS and disability status, with 77% of participants classified as having substantial fatigue, based on the criteria of a mean FSS score ≥4. The MFIS (ICC=0.863) and the FSS (ICC=0.751) had acceptable reliability over six months. Precision was reasonable for both scales (based on SEM and CV estimates) but better for the FSS. MDC estimates were established and were lower for the FSS. CONCLUSION: Reliability of the FSS and MFIS falls within acceptable ranges, and precision and clinically important change estimates provide guidelines for interpreting change in scores from these outcomes in clinical research of intervention and rehabilitation approaches for managing fatigue.

Symptomatic correlates of six-minute walk performance in persons with multiple sclerosis.

BACKGROUND: The six-minute walk (6MW) test has been identified as a valid, reliable, and reproducible measure of endurance walking performance that differentiates persons with multiple sclerosis (MS) and controls and correlates with disability and walking impairment. AIM: This study examined symptoms of fatigue, pain, and depression as correlates of 6MW performance and the possibility that such symptoms would account for the difference in 6MW distance between persons with MS and controls. DESIGN: Observational. SETTING: Research laboratory. POPULATION: Sixty-six persons, 33 with MS and 33 controls matched on age, sex, height, and weight. METHODS. Participants completed the fatigue severity scale (FSS), short-form of the McGill pain questionnaire (SF-MPQ), and depression items of the hospital anxiety and depression scale (HADS-D) and then performed the six-minute walk (6MW) in a rectangular corridor. RESULTS: There were statistically significant differences between groups in 6MW distance (p = 0.0001) and FSS (P=0.0001) and SF-MPQ (P=0.025), but not HADS-D (P>0.05), scores. 6MW distance was significantly correlated with FSS (P=-0.66), SF-MPQ (P=-0.38), and HADS-D (P=-0.33) scores in the overall sample, but 6MW distance was significantly correlated with only FSS scores in the separate samples of those with MS (P=-0.46) and controls (P=-0.46). Only group (ß=0.32) and FSS scores (ß=-0.53) explained variance in overall 6MW distance in a hierarchical, linear regression analysis. CONCLUSION: This study provides new insight into the symptomatic correlates of 6MW performance and identifies fatigue as a possible target of interventions designed to improve walking endurance in MS. CLINICAL REHABILITATION IMPACT: Clinicians and practitioners might consider targeting fatigue as a method of managing compromised endurance walking in persons with MS.

Accelerometry as a measure of walking behavior in multiple sclerosis.

OBJECTIVE: Accelerometry has been identified as a possible ecologically valid and objective approach for measuring community ambulation in multiple sclerosis (MS). This study provides a validation of accelerometer output based on associations with Expanded Disability Status Scale (EDSS), Patient Determined Disease Steps (PDDS) Scale, and Multiple Sclerosis Walking Scale-12 (MSWS-12) scores, timed 25-foot walk (T25FW) and 6-min walk (6MW) performance, oxygen cost (O(2) cost) of walking, and spatial and temporal parameters of gait. MATERIALS AND METHODS: 256 persons with MS completed the PDDS and MSWS-12, underwent an examination for the generation of an EDSS score, undertook two T25FW tests and a 6MW while wearing a portable metabolic unit for measuring the O(2) cost of walking, completed two trials of comfortable walking on a GAITRite electronic walkway for measuring spatial and temporal parameters of gait, and then wore an Actigraph accelerometer during the waking hours of a 7-day period. RESULTS: The accelerometer output was significantly correlated with EDSS (ρ = -0.522), PDDS (ρ = -0.551), and MSWS-12 (ρ = -0.617) scores, T25FW (ρ = -0.595) and 6MW (ρ = 0.630) performance, and O(2) cost of walking (ρ = -0.457). Regarding gait parameters, the accelerometer output was significantly correlated with velocity (ρ = 0.420), cadence (ρ = 0.349), step time (ρ = -0.353), step length (ρ = 0.395), double support (ρ = -0.424), and single support (ρ = 0.400). CONCLUSION: We provide comprehensive evidence from a large sample of persons with MS that further supports accelerometry as a measure of walking behavior.

Physical activity and multiple sclerosis: new insights regarding inactivity.

OBJECTIVES: There is increasing recognition that physical activity has beneficial consequences among persons with multiple sclerosis (MS), but there is concern regarding the current degree of physical inactivity in this population because of limitations with previous research and increased recognition of health behaviors in MS. This study compared physical activity levels between large samples of persons with mild MS and matched controls using validated measures of physical activity. MATERIALS AND METHODS: The sample included 77 cases of MS and 77 controls matched on age, height, weight, and gender. Physical activity was assessed using five measures, namely the Godin Leisure-Time Exercise Questionnaire (GLTEQ), International Physical Activity Questionnaire (IPAQ), and activity counts per day, step counts per day, and time spent in moderate-to-vigorous physical activity (MVPA) per day by accelerometry. RESULTS: There were statistically significant differences between groups in accelerometer activity counts (t = -3.87, P = 0.0001), accelerometer step counts (t = -4.29, P = 0.0001), time spent in MVPA (t = -2.39, P = 0.01), GLTEQ scores (t = -3.83, P = 0.0001), and IPAQ scores (t = -3.42, P = 0.0001). The average effect size across all five measures was d = -0.59 and indicated that persons with MS overall were moderately less physically active than the matched controls. CONCLUSIONS: The primary finding was a moderate reduction in physical activity among those with MS, but the magnitude was substantially smaller than reported in a published meta-analysis. Importantly, the degree of physical inactivity can likely be overcome through the delivery of behavioral interventions for increasing physical activity and this should translate into meaningful consequences for persons with MS.