Physical inactivity, neurological disability, and cardiorespiratory fitness in multiple sclerosis

Body composition in multiple sclerosis

Multiple sclerosis affects central nervous system leading to disability. Among other complications the deterioration of body composition is usually neglected and increases the risk for diseases such as coronary heart disease, non-insulin dependent diabetes mellitus, lipid abnormalities and bone loss leading to fractures in this population. Body mass index values, the effect of spasticity, the increased number of drugs used and the relationship between skeletal muscle and bone which interacts with impaired motor function leading to body composition alterations in multiple sclerosis are reviewed.

Randomized controlled trial of a teleconference fatigue management plus physical activity intervention in adults with multiple sclerosis: rationale and research protocol

BACKGROUND

Chronic fatigue and inactivity are prevalent problems among individuals with multiple sclerosis (MS) and may independently or interactively have detrimental effects on quality of life and ability to participate in life roles. However, no studies to date have systematically evaluated the benefits of an intervention for both managing fatigue and promoting physical activity in individuals with MS. This study involves a randomized controlled trial to examine the effectiveness of a telehealth intervention that supports individuals with MS in managing fatigue and increasing physical activity levels.

METHODS/DESIGN

A randomly-allocated, three-parallel group, time-series design with a social support program serving as the control group will be used to accomplish the purpose of the study. Our goal is to recruit 189 ambulatory individuals with MS who will be randomized into one of three telehealth interventions: (1) a contact-control social support intervention, (2) a physical activity-only intervention, and (3) a physical activity plus fatigue management intervention. All interventions will last 12 weeks and will be delivered entirely over the phone. Our hypothesis is that, in comparison to the contact-control condition, both the physical activity-only intervention and the physical activity plus fatigue management intervention will yield significant increases in physical activity levels as well as improve fatigue and health and function, with the physical activity plus fatigue management intervention yielding significantly larger improvements. To test this hypothesis, outcome measures will be administered at Weeks 1, 12, and 24. Primary outcomes will be the Fatigue Impact Scale, the Godin Leisure-Time Exercise Questionnaire (GLTEQ), and Actigraph accelerometers. Secondary outcomes will include the SF-12 Survey, Mental Health Inventory, Multiple Sclerosis Impact Scale, the Community Participation Indicator, and psychosocial constructs (e.g., self-efficacy).

DISCUSSION

The proposed study is novel, in that it represents a multi-disciplinary effort to merge two promising lines of research on MS: fatigue management and physical activity promotion. Collectively, the proposed study will be the largest randomized controlled trial to examine the effects of a lifestyle physical activity intervention in people with MS.

TRIAL REGISTRATION

NCT01572714.

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.

The benefits of exercise training in multiple sclerosis

Multiple sclerosis (MS) is an immune-mediated disease characterized by inflammatory demyelination and neurodegeneration within the CNS. This damage of CNS structures leads to deficits of body functions, which, in turn, affect patient activities, such as walking, and participation. The pathogenesis and resulting consequences of MS have been described as concepts within the International Classification of Functioning, Disability and Health (ICF) model--an international standard to describe and measure health and disability. Evidence suggests that exercise training in people with MS has the potential to target and improve many of the components outlined in the ICF model. Although the body of research examining the effects of exercise training on depression, cognition and participatory outcomes is not sufficiently developed, some preliminary evidence is promising. Exercise training is proposed to affect inflammation, neurodegeneration, and CNS structures, but current evidence is limited. In this Review, we discuss evidence from clinical trials that suggests beneficial effects of exercise training on muscle strength, aerobic capacity and walking performance, and on fatigue, gait, balance and quality of life. Issues with current studies and areas of future research are highlighted.

Vascular dysfunction and physical activity in multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is an inflammatory disorder of the brain and spinal cord. Disability status and progression are associated with reduced physical activity (PA) and cardiovascular function. Lack of adequate PA combined with inflammation may create high susceptibility to subclinical atherosclerosis and vascular dysfunction.

PURPOSE

The purpose of this study was to compare subclinical atherosclerosis and arterial function between individuals with and without MS matched for age, sex, and body mass index.

METHODS

Thirty-three individuals diagnosed with MS and 33 controls underwent strain gauge plethysmography for resting forearm blood flow (FBF) and peak reactive hyperemia for the microvascular function. Intima-media thickness and arterial compliance (AC) were measured using carotid ultrasound for vascular function. C-reactive protein and PA (7-d accelerometer data) were also measured.

RESULTS

There was a significant difference (P < 0.05) in resting FBF, peak reactive hyperemia, central pulse wave velocity, and AC between the MS and control groups. PA was associated with peak FBF and central pulse wave velocity but not FBF and carotid AC. Individuals with MS exhibit reduced arterial function but similar intima-media thickness compared with controls. Persons with MS had significantly reduced PA levels compared with controls, and PA accounted for differences in arterial function between groups.

CONCLUSIONS

These results indicate that subclinical markers of atherosclerosis are higher in individuals with MS, suggesting a higher risk of cardiovascular disease in this population. However, the higher levels of subclinical atherosclerosis were accounted for by the low PA in persons with MS, suggesting that increasing PA may reduce the increase in cardiovascular disease risk in patients with MS.

Energy cost of walking and its association with gait parameters, daily activity, and fatigue in persons with mild multiple sclerosis

BACKGROUND

Energy cost of walking (C(w)) is elevated in persons with multiple sclerosis (MS), perhaps because of gait impairment, and may impact daily activity and fatigue.

OBJECTIVE

The authors examined for associations between C(w), spatiotemporal gait parameters, daily activity, and perceived fatigue in persons with mild MS.

METHODS

Forty-four participants completed 4 trials of walking on a GAITRite mat and one 6-minute trial of walking on a treadmill at a constant, controlled speed of 54 m min(-1) while expired gases were analyzed for oxygen consumption. Participants also completed the Fatigue Severity Scale (FSS) and wore a waist-mounted accelerometer for 7 days.

RESULTS

C (w) was significantly and inversely associated with gait speed (r = -.25) and stride length (r = -.32) and positively associated with double limb support (r = .27). C (w) was significantly and inversely associated with daily accelerometer activity counts (r = -.35) and positively associated with FSS scores (ρ = .31).

CONCLUSION

The results support the development and application of rehabilitation strategies to address impaired gait parameters as an approach to improve C(w), daily activities, and fatigue.

Walking impairment in patients with multiple sclerosis: exercise training as a treatment option

Multiple sclerosis (MS) is a chronic disease of the central nervous system that culminates in the progression of physical and cognitive disability over time. Walking impairment is a ubiquitous feature of MS and a sentinel characteristic of the later or advanced stages of the disease. This paper presents a conceptual rationale along with empirical evidence for exercise training as a rehabilitation approach for managing walking impairment and improving walking function in persons with MS. Conceptually, MS is associated with a decrease in physical activity, which, in turn, can result in deconditioning across multiple domains of physiological functioning. The resulting deconditioning feeds back and further drives physical inactivity until a threshold is reached that likely initiates the progression of walking impairment in MS. Empirically, physical activity and exercise training have been associated with beneficial effects on walking function in persons with MS. This is based on cross-sectional, longitudinal, and experimental research that included diversity in the breadth of measures of walking, persons with MS, and exercise/physical activity characteristics. Of particular importance, future researchers might consider examining the combinatory effects of exercise training plus pharmacological agents on walking mobility in MS. Collectively, exercise training and physical activity might hold significant potential for the management of progressive mobility disability in MS.