Accelerometer measured physical activity and sedentary time in individuals with multiple sclerosis versus age matched controls: A systematic review and meta-analysis

Reduced physical activity in multiple sclerosis: The role of gait parameters, gait variability parameters and self-reported measure of gait

BACKGROUND

It is important to understand the gait disorders that lead to physical inactivity in patients with multiple sclerosis (PwMS). The objective of this study was to evaluate the relationship between physical activity (PA) and gait in PwMS in a holistic manner, employing objective, subjective and patient perspective methods.

METHODS

The study cohort comprised 30 PwMS. PA was evaluated using a SenseWear Armband and the International Physical Activity Questionnaire. The gait was evaluated using the 10 Meter Walk Test, the Timed Up and Go Test, the GAITRite Analysis System, and the 12-item Multiple Sclerosis Walking Scale. Moreover, the gait variability was calculated using the data obtained from the GAITRite Analysis System.

RESULTS

The findings of this study indicate that the walking Metabolic Equivalent of Task (MET) value was moderately correlated with the results of both clinical gait parameters and objective gait analysis results. The moderate correlation between the moderate/total MET results and step length variability was also observed. The step count results demonstrated a moderate correlation with both clinical gait parameters and objective gait analysis results, as well as with parameters of gait variability (p < 0.05).

CONCLUSION

The findings of our study indicate that PwMS with higher step counts and walking MET values demonstrated superior gait performance, reduced gait variability, and enhanced gait stability. These findings support the potential value of targeting leisure-time PA as a behavioural strategy for the prevention of gait disturbances in PwMS.

Differences in physical activity between individuals with multiple sclerosis and healthy adults in Central Europe

BACKGROUND

The health benefits of regular exercise and physical activity in people with multiple sclerosis (MS) have been described in numerous studies. Despite this, research from global and North American populations suggests that people with MS are less physically active. However, not enough data are available from Central European countries. To address this gap we conducted a study to evaluate the physical activity of people with MS and to compare it with a group of healthy controls.

METHODS

Physical activity levels were assessed using the Godin Leisure-Time Exercise Questionnaire (GLTEQ) for both the MS and healthy control groups. The Pearson χ2 test was employed to analyse the effect of age, gender and BMI on physical activity-category (GLTEQ) within the MS and HC groups.

RESULTS

The study included 729 participants, comprising 354 individuals with MS and 375 healthy controls. Participants with MS exhibited substantially lower levels of physical activity than the healthy controls (p < 0.001) and engaged in exercise less frequently and regularly (p < 0.001). Lack of time was the primary barrier to participation in physical activity for both groups. However, physical limitations were a common obstacle for individuals with MS, whereas healthy controls more often cited the absence of equipment or other reasons. Women with MS were significantly more likely to abstain from physical activity, while men with MS were more likely to exercise regularly. Unlike healthy controls, the level of physical activity in individuals with MS was not influenced by BMI.

CONCLUSION

Compared to healthy individuals, people with MS have reduced levels of physical activity and are less likely to exercise regularly. They also experience various barriers and motivational factors affecting their physical activity.

Internet-based exercise and physical activity promotion for persons with multiple sclerosis: a randomized controlled trial

BACKGROUND

We evaluated the effects of a 12-week internet-based exercise and physical activity promotion program for persons with multiple sclerosis.

METHODS

We performed a multicenter, randomized, waitlist-controlled study. The intervention group (IG) received the 12-week program, followed by 12 weeks with usual care. The control group (CG) received usual care only. The main components of the 12-week program were: (1) a tailored home-based exercise prescription, (2) e-learning resources, (3) telephone and video meetings with an exercise therapist, (4) the provision of a consumer-based PA monitor. Measurements were taken at baseline, postintervention, and after 24 weeks. The primary outcome was device-measured steps/day. Other outcomes were device-measured moderate-to-vigorous physical activity, subjectively measured leisure-time and transportation physical activity and sport/exercise, physical activity-related health competence, walking ability, quality of life, fatigue, depression, and PA-related self-concordance. We compared changes from baseline to postintervention between groups and analyzed changes in the IG during the follow-up.

RESULTS

Analysis of 56 persons with multiple sclerosis (IG: n = 29, CG: n = 27, age: 45.6 ± 10.9) revealed no significant intervention effect on steps/day. However, significant improvements were observed in moderate-to-vigorous physical activity, sport/exercise, control competence, fatigue, and quality of life (physical). During the follow-up, sport/exercise and quality of life decreased significantly. Leisure-time and transportation physical activity increased significantly.

CONCLUSIONS

Our study provides first evidence that the developed program can increase control competence, aspects of physical activity and health in persons with multiple sclerosis. A trial with a larger sample is recommended to confirm our results and examine intervention mechanisms.

TRIAL REGISTRATION

Registry: Clinicaltrials.gov; registration number: NCT04367389; date of registration: 2020-04-21 (retrospectively registered).

Impact of Usual-Care Physiotherapy on Physical Activity and Self-Efficacy in People With Multiple Sclerosis: An Observational Longitudinal Study

BACKGROUND

People with multiple sclerosis (MS) experience motor and nonmotor symptoms that affect daily life. Although regular physical activity (PA) may enhance the overall well-being of people with MS, they tend to have lower activity levels than healthy individuals. This study aims to investigate the impact of usual-care physiotherapy on PA and self-efficacy in people with MS and identify prerehabilitation factors that influence positive changes in PA with physiotherapy.

METHODS

Forty-one people with MS undergoing physiotherapy with a median (IQR) age of 54.00 (17.00) years and an Expanded Disability Status Scale score of 6.00 (2.00) points were assessed on the first days (T0) and last days of their rehabilitation period (T1), and 6 weeks after it ended (T2). Instrumental assessment utilized Fitbit Versa trackers, measuring daily steps and moderate/vigorous PA engagement (MVPA). Self-efficacy, perceived fatigue, walking ability, and quality of life were measured using the Self-Efficacy in Multiple Sclerosis scale (SEMS), the Fatigue Severity Scale, the 10-Meter Walk Test, and the Short Form-12 Health Survey.

RESULTS

Usual-care physiotherapy did not improve (P > .05) daily steps (T0: 4139 [3333]; T1: 4438 [2505] steps per day), MVPA (T0: 6.00 [15.6]; T1: 10.52 [16.30] minutes per day), or self-efficacy (SEMS: T0: 42.0 [10.8]; T1: 40.5 [8.7] points). Low perceived fatigue, better overall PA, and good physical health perception were identified as predictors of positive changes in PA after physiotherapy.

CONCLUSIONS

Usual-care physiotherapy focusing on mobility did not result in significant improvements in PA or self-efficacy for people with MS. Perceived fatigue and overall PA before physiotherapy impacted PA levels after rehabilitation. Future interventions may benefit from integrating motivational strategies into the rehabilitation protocol to increase PA levels.

Accelerometry-Assessed Physical Activity and Circadian Rhythm to Detect Clinical Disability Status in Multiple Sclerosis: Cross-Sectional Study

Background

Tools for measuring clinical disability status in people with multiple sclerosis (MS) are limited. Accelerometry objectively assesses physical activity and circadian rhythmicity profiles in the real-world environment and may potentially distinguish levels of disability in MS.

Objective

This study aims to determine if accelerometry can detect differences in physical activity and circadian rhythms between relapsing-remitting multiple sclerosis (RRMS) and progressive multiple sclerosis (PMS) and to assess the interplay within person between the 2 domains of physical activity (PA) and circadian rhythm (CR) in relation to MS type.

Methods

This study represents an analysis of the baseline data from the prospective HEAL-MS (home-based evaluation of actigraphy to predict longitudinal function in multiple sclerosis) study. Participants were divided into 3 groups based on the Expanded Disability Status Scale (EDSS) criteria for sustained disability progression: RRMS-Stable, RRMS-Suspected progression, and PMS. Baseline visits occurred between January 2021 and March 2023. Clinical outcome measures were collected by masked examiners. Participants wore the GT9X Link ActiGraph on their nondominant wrists for 2 weeks. After adjusting for age, sex, and BMI, a logistic regression model was fitted to evaluate the association of each accelerometry metric with odds of PMS versus RRMS. We also evaluated the association of accelerometry metrics in differentiating the 2 RRMS subtypes. The Joint and Individual Variation Explained (JIVE) model was used to assess the codependencies between the PA and CR domains and their joint and individual association with MS subtype.

Results

A total of 253 participants were included: 86 with RRMS-Stable, 82 with RRMS-Suspected progression, and 85 with PMS. Compared to RRMS, participants with PMS had lower total activity counts (β=-0.32, 95% CI -0.61 to -0.03), lower time spent in moderate to vigorous physical activity (β=-0.01, 95% CI -0.02 to -0.004), higher active-to-sedentary transition probability (β=5.68, 95% CI 1.86-9.5), lower amplitude (β=-0.0004, 95% CI -0.0008 to -0.0001), higher intradaily variability (β=4.64, 95% CI 1.45-7.84), and lower interdaily stability (β=-4.43, 95% CI -8.77 to -0.10). Using the JIVE model for PA and CR domains, PMS had higher first joint component (β=0.367, 95% CI 0.088-0.656), lower PA-1 component (β=-0.441, 95% CI -0.740 to -0.159), and lower PA-2 component (β=-0.415, 95% CI -0.717 to -0.126) compared to RRMS. No significant differences were detected between the 2 RRMS subtypes except for lower relative amplitude in those with suspected progression (β=-5.26, 95% CI -10.80 to -0.20).

Conclusions

Accelerometry detected differences in physical activity patterns between RRMS and PMS. More advanced analytic techniques may help discern differences between the 2 RRMS subgroups. Longitudinal follow-up is underway to assess the potential for accelerometry to detect or predict disability progression.

Quantifying shoulder motion in the free-living environment using wearable inertial measurement units: Challenges and recommendations

Understanding function and dysfunction of the shoulder may be best addressed by capturing the motion of the shoulder in the unstructured, free-living environment where the magnitudes and frequencies of required daily motion can be quantified. Miniaturized wearable inertial measurement units (IMUs) enable measurement of shoulder motion in the free-living environment; however, there are challenges in using IMU-based data to estimate traditionally used measures of shoulder motion from lab-based motion capture. There are limited options for IMU placement/fixation that minimize soft tissue effects and there are significant challenges in developing the algorithms that can accurately estimate shoulder joint angles from IMU measurements of acceleration and angular velocity. In an effort to collate current knowledge and highlight solutions to addressable challenges, in this paper, we report the results of a focused search of research articles using IMUS for kinematic measurements of the shoulder in the free-living environment, discuss the basic steps required for quantifying shoulder motion in the non-laboratory field-based setting using wearable IMUs, and we discuss the challenges that must be overcome in the context of the shoulder joint and the literature review. Finally, we suggest some IMU-based measures that are less sensitive to experimental design and algorithm choices, make recommendations for the information documented in manuscripts describing studies that use IMUs to quantify shoulder motion, and propose directions for future research.

Within-person changes in objectively measured activity levels as a predictor of brain atrophy in multiple sclerosis

Objective

The evaluate the association between changes in accelerometry-derived activity patterns and brain atrophy in people with multiple sclerosis (PwMS).

Methods

We included PwMS aged ≥40 years with approximately annual brain MRI who wore GT9X Actigraph accelerometers every three months over two years. Functional principal components analysis (fPCA) summarized overall activity and timing. Additional indices included total and 2-hour specific activity, sedentary time, and circadian rhythm parameters. Whole brain segmentation used SLANT-CRUISE. Generalized estimating equations quantifying between- and within-person effects modeled associations between accelerometry changes and MRI outcomes, adjusting for demographic and clinical factors.

Results

We included 233 PwMS (mean age: 54.4 years, SD: 8.6, 30% male) who wore accelerometers an average of 6.3 times over 58 days across two years. fPCA showed within-person increases in the first fPC, representing low nighttime and high morning activity, were associated with slower brain atrophy (per 1 SD increase: 0.24%; 95% CI: 0.10, 0.40; p=0.0009). Similarly, a 10% increase in 8:00-10:00 AM activity was associated with 0.49% higher whole brain volume (95% CI: 0.19, 0.79; p=0.001) over time, while increased nighttime activity (0:00-2:00) was linked to -0.28% brain volume loss (95% CI: -0.48, -0.08; p=0.007). Higher moderate-to-vigorous activity and daytime activity were associated with greater brain volume preservation longitudinally.

Interpretation

Changes in activity patterns, particularly increased nighttime activity and reduced morning activity, are linked to brain atrophy in PwMS. Accelerometry offers a scalable, sensitive method for tracking MS progression and may be beneficial as a recruitment or outcome measure in trials.

Cardiovascular comorbidities, mental health, and physical activity in persons with multiple sclerosis

This study examined the associations among cardiovascular comorbidities, symptoms of depression and anxiety, and physical activity in persons with multiple sclerosis. Participants with multiple sclerosis (N = 217) completed demographic, cardiovascular comorbidity, depression, and anxiety self-report measures, and wore an accelerometer for 7 days. We examined the bivariate, non-parametric correlations among the variables and conducted parametric, independent samples t-tests when examining the differences in variables based on cardiovascular comorbidity status. Bivariate correlation analysis indicated that there were statistically significant associations between anxiety scores, but not depression scores, and cardiovascular comorbidities. Physical activity, especially moderate-to-vigorous physical activity (MVPA), was correlated with cardiovascular comorbidities. There were small significant differences based on hyperlipidemia status in anxiety scores (p = 0.015, d = -0.42), MVPA (p < 0.001, d = 0.44), and steps/day (p < 0.001, d = 0.50), and based on hypertension status in anxiety scores (p = 0.010, d = -0.35), depression scores (p = 0.046, d = -0.26), MVPA (p = 0.003, d = 0.41), and steps/day (p < 0.001, d = 0.53). The findings indicate that there are significant associations among cardiovascular comorbidities, symptoms of depression and anxiety, and physical activity in persons with multiple sclerosis. Physical activity, specifically MVPA, may be a target for managing those outcomes in persons with multiple sclerosis.

Comprehensive evaluation of accelerometer-based physical activity in persons with multiple sclerosis - The influence of disability status and its impact on walking capacity

INTRODUCTION

Multiple sclerosis has a substantial negative impact on physical activity (PA). However, limited knowledge exists on objectively measured PA levels and types across disability status along with its influence on walking capacity.

OBJECTIVES

To (1) determine PA levels/types in persons with MS (pwMS) (overall and across disability status) and in healthy controls (HC), and (2) investigate the association between PA levels/types and walking capacity.

METHODS

In this study (n = 280 pwMS, n = 118 HC), pwMS were stratified into subgroups based on the Expanded Disability Status Scale (EDSS): no disability (EDSS 0-1.5), mild (EDSS 2-2.5), moderate (EDSS 3-4.5), and severe (EDSS 5-6.5). PA levels/types were assessed by thigh-worn accelerometry and walking capacity by 2-min Walk Test (2MWT), Six Spot Step Test (SSST), and Timed 25-foot Walk Test (T25FWT). Simple and multiple linear regression analyses were used to investigate associations between PA levels/types and walking capacity in pwMS.

RESULTS

PA levels/types and walking capacity differed (p < 0.05) between HC and pwMS, and this was especially pronounced for counts per minute (CPM) (774±297 vs. 518±261), sedentary time (558±59 vs. 588±82 min), moderate-to-vigorous physical activity (MVPA) (47±26 vs. 27±22 min), and walking (94±33 vs. 75±38 min) with differences being accentuated with advanced disability. PA levels/types were associated with walking capacity (p < 0.001, r2 = 0.04-0.31), which remained after adjusting for age, sex, Body Mass Index (BMI), EDSS, and time since diagnosis (r2 = 0.42-0.57). Importantly, certain PA levels outcomes (light PA (LPA) and moderate-to-vigorous PA (MVPA)) and PA types outcomes (walking) were independently associated with walking capacity.

CONCLUSION

The present cross-sectional study observed that PA levels and types were negatively impacted in pwMS compared to HC, especially with advanced disability status. Furthermore, PA levels (LPA and MVPA in particular) and PA types (walking in particular) were associated with walking capacity, independently of age, sex, BMI, and disability status.

Elaborating the knowledge structure and emerging research trends of physical activity for multiple sclerosis: A bibliometric analysis from 1994 to 2023

BACKGROUND

Multiple sclerosis is a common inflammatory neurological disease among young adults and is the tenth leading cause of the global burden of disease. Existing common treatments such as pharmacological and palliative therapies do not control the neurodegenerative process or cure multiple sclerosis. Numerous epidemiological surveys, randomised controlled trials, and systematic reviews with meta-analyses support the effects of physical activity on health-related outcomes among patients with multiple sclerosis. Moreover, bibliometric analysis can provide a broad evidence synthesis beyond systematic reviews and meta-analyses, allowing researchers and other stakeholders to obtain a one-stop overview of this research field. Therefore, this bibliometric analysis aims to provide insight into the knowledge structure of the field of physical activity for multiple sclerosis over the past three decades, and to predict emerging research trends.

METHODS

This study strictly complied with step-by-step guidelines of bibliometric analysis, combining performance analysis and science mapping. Four indexes from the Web of Science Core Collection were selected as data sources, and articles and review articles in the field of physical activity for multiple sclerosis from 1994 to 2023 were included in this analysis. Mircrosoft Excel, RStudio, VOSviewer 1.6.20, and CiteSpace 6.3.R1 (64-bit) Advanced were used to perform performance analysis and science mapping.

RESULTS

Over the past three decades, this field published a total of 1,271 documents, with the scientific output showing a rapid upward trend over the past two decades. Robbert W Motl was the most prolific author in this field, with a total of 300 publications. The USA contributed nearly half of the publications in this field (549 documents), and the University of Illinois System was the institution with the highest number of publications (222 documents). Multiple Sclerosis and Related Disorders was the journal that published the highest number of documents in this field (117 documents), while more than a third of this field's publications were included in the category: Clinical Neurology (438 documents). The Reference co-citation analysis identified three main research trends, including shifts in research methodology, changes in health outcomes in randomised controlled trials, and shifts in different types of physical activity interventions. Combining the results from reference co-citation analysis and citation burst analysis, the combination of behaviour change technique and telerehabilitation may be the emerging research trend.

CONCLUSION

This bibliometric analysis identifies rapid growth in the field of physical activity for multiple sclerosis over the past two decades. Moreover, the combination of performance analysis and science mapping provides insight into knowledge structure in this field and informed future research trends for researchers and the relevant stakeholders.

The therapeutic potential of exercise for improving mobility in multiple sclerosis

Multiple sclerosis (MS) is a chronic autoimmune disease characterized by inflammation and demyelination in the central nervous system (CNS) with subsequent axonal and neuronal degeneration. These changes are associated with a broad range of symptoms including skeletal muscle dysfunction. Importantly, musculoskeletal impairments manifest in various ways, compromise the quality of life and often precede the later development of mobility disability. As current standard disease modifying therapies for MS predominantly act on neuroinflammation, practitioners and patients face an unmet medical need for adjunct therapies specifically targeting skeletal muscle function. This review is intended to detail the nature of the skeletal muscle dysfunctions common in people with MS (pwMS), describe underlying intramuscular alterations and outline evidence-based therapeutic approaches. Particularly, we discuss the emerging role of aerobic and resistance exercise for reducing the perception of fatigue and increasing muscle strength in pwMS. By integrating the most recent literature, we conclude that both exercise interventions should ideally be implemented as early as possible as they can address MS-specific muscle impairments. Aerobic exercise is particularly beneficial for pwMS suffering from fatigue and metabolic impairments, while resistance training efficiently counters muscle weakness and improves the perception of fatigue. Thus, these lifestyle interventions or possible pharmacological mimetics have the potential for improving the general well-being and delaying the functional declines that are relevant to mobility.

The association of fear of falling and falls with sedentary behavior in people with multiple sclerosis

OBJECTIVE

Sedentary behavior, falls, and fear of falling (FoF) are specific concerns for people with MS (pwMS). Considering the relatively high incidence and potential linkage, it is surprising that this triple relationship has as yet not been extensively investigated in pwMS. Thus, the present study aimed to examine the correlates of sedentary behavior with FoF and falls in pwMS.

METHODS

Fifty pwMS, 30 women, were admitted to this cross-sectional study. Primary outcome measures included physical activity and sedentary behavior metrics measured by accelerometry, fall status, and FoF. Additional measures included mobility clinical tests, cognition, perceived fatigue, depression, and anxiety. The sample was divided into two subgroups according to the daily Metabolic Equivalent of Task (MET) rate scores; <1.5 was defined as sedentary, ≥1.5 were defined as non-sedentary. Multivariate analysis of variance and linear regression analyses assessed the relationships by using an alpha of 0.05.

RESULTS

Sixty-four percent of the sample were classified as sedentary. The sedentary subgroup reported more FoF than the non-sedentary subgroup (32.5 (S·D. = 11.3) vs. 29.9 (S.D. = 9.5); however, no differences were found in fall status between the subgroups. No differences were found for depression, anxiety, cognition, and perceived fatigue between the subgroups. Furthermore, according to the linear regression analysis, FoF explained 23.9% of the variance pertaining to the daily MET rate when controlling for age, gender, disease duration, and disability.

CONCLUSIONS

Clinicians are encouraged to incorporate the issue of FoF during standard management, which may represent an opportunity to improve care and reduce sedentary behavior in pwMS.

Age and asymmetry of corticospinal excitability, but not cardiorespiratory fitness, predict cognitive impairments in multiple sclerosis

Background

Cognitive impairment is a disabling and underestimated consequence of multiple sclerosis (MS), with multiple determinants that are poorly understood.

Objectives

We explored predictors of MS-related processing speed impairment (PSI) and age-related mild cognitive impairment (MCI) and hypothesized that cardiorespiratory fitness and corticospinal excitability would predict these impairments.

Methods

We screened 73 adults with MS (53 females; median [range]: Age 48 [21-70] years, EDSS 2.0 [0.0-6.5]) for PSI and MCI using the Symbol Digit Modalities Test and Montréal Cognitive Assessment, respectively. We identified six persons with PSI (No PSI, n = 67) and 13 with MCI (No MCI, n = 60). We obtained clinical data from medical records and self-reports; used transcranial magnetic stimulation to test corticospinal excitability; and assessed cardiorespiratory fitness using a graded maximal exercise test. We used receiver operator characteristic (ROC) curves to discern predictors of PSI and MCI.

Results

Interhemispheric asymmetry of corticospinal excitability was specific for PSI, while age was both sensitive and specific for MCI. MS-related PSI was also associated with statin prescriptions, while age-related MCI was related to progressive MS and GABA agonist prescriptions. Cardiorespiratory fitness was associated with neither PSI nor MCI.

Discussion

Corticospinal excitability is a potential marker of neurodegeneration in MS-related PSI, independent of age-related effects on global cognitive function. Age is a key predictor of mild global cognitive impairment. Cardiorespiratory fitness did not predict cognitive impairments in this clinic-based sample of persons with MS.

Accelerometry measures of physical activity and sedentary behavior: Associations with cognitive functioning in MS

BACKGROUND

Cognitive dysfunction is a pervasive symptom of multiple sclerosis (MS). Correlational evidence on the relationships between physical activity, sedentary behavior, and cognition has been mixed and limited to a few activity measures. The collinearity of accelerometry-based metrics has precluded an assessment of the full activity spectrum. Here, we aimed to examine the rich set of activity measures using analytic approaches suitable for collinear metrics. We investigated the combination of physical activity, sedentary, and clinicodemographic measures that explain the most variance in composite scores of working memory/processing speed, visual memory, and verbal memory.

METHODS

We analyzed baseline accelerometry and neuropsychological data (n = 80) from a randomized controlled trial of pedometer tracking. Using partial least squares regression (PLSR), we built three models to predict latent scores on the three domains of cognition using 12 activity metrics, sex, education, and Expanded Disability Status Scale (EDSS) scores. Significance was assessed using linear regression models with model component scores as predictors and cognitive composites as outcomes.

RESULTS

The latent component was significant for working memory/processing speed but was not significant for visual memory and verbal memory after Bonferroni correction. Working memory/processing speed was positively associated with average kilocalories, moderate-to-vigorous physical activity (MVPA), steps, and sex (i.e., higher scores in males) and negatively related to duration of long sedentary bouts and EDSS.

CONCLUSIONS

These findings suggest that increasing overall energy expenditure through walking and MVPA, while decreasing prolonged sedentary time may positively benefit working memory/processing speed in people with MS.

TRIAL REGISTRATION

This RCT #NCT03244696 was registered on Clinicaltrials.gov (https://www.

CLINICALTRIALS

gov/ct2/show/NCT03244696).

Free-Living Peak Cadence in Multiple Sclerosis: A New Measure of Real-World Walking?

BACKGROUND

Physical function and walking performance have become important outcomes in clinical trials and rehabilitation involving persons with multiple sclerosis (MS). However, assessments conducted in controlled settings may not reflect real-world capacity and movement in a natural environment. Peak cadence via accelerometry might represent a novel measure of walking intensity and prolonged natural effort under free-living conditions.

OBJECTIVE

We compared peak 30-minute cadence, peak 1-minute cadence, and time spent in incremental cadence bands between persons with MS and healthy controls, and examined the associations between peak cadence and laboratory-assessed physical function and walking performance.

METHODS

Participants (147 MS and 54 healthy controls) completed questionnaires on disability status and self-reported physical activity, underwent the Short Physical Performance Battery, Timed 25-Foot Walk, Timed Up and Go, and 6-Minute Walk, and wore an accelerometer for 7 days. We performed independent samples t-tests and Spearman bivariate and partial correlations adjusting for daily steps.

RESULTS

The MS sample demonstrated lower physical function and walking performance scores, daily steps, and peak cadence (P < .001), and spent less time in purposeful steps and slow-to-brisk walking (40-119 steps/minutes), but accumulated more incidental movement (1-19 steps/minutes) than healthy controls. The associations between peak cadence and performance outcomes were strong in MS (|rs| = 0.59-0.68) and remained significant after controlling for daily steps (|prs| = 0.22-0.44), P-values < .01. Peak cadence was inversely correlated with age and disability, regardless of daily steps (P < .01).

CONCLUSIONS

Our findings provide preliminary evidence for the potential use of peak cadence with step-based metrics for comprehensively evaluating free-living walking performance in MS.

Abnormal thalamic functional connectivity correlates with cardiorespiratory fitness and physical activity in progressive multiple sclerosis

BACKGROUND

Altered thalamic volumes and resting state (RS) functional connectivity (FC) might be associated with physical activity (PA) and cardiorespiratory fitness (CRF) in people with progressive multiple sclerosis (PMS).

OBJECTIVES

To assess thalamic structural and functional alterations and investigate their correlations with PA/CRF levels in people with PMS.

METHODS

Seven-day accelerometry and cardiopulmonary exercise testing were used to assess PA/CRF levels in 91 persons with PMS. They underwent 3.0 T structural and RS fMRI acquisition with 37 age/sex-matched healthy controls (HC). Between-group comparisons of MRI measures and their correlations with PA/CRF variables were assessed.

RESULTS

PMS people had lower volumes compared to HC (all p < 0.001). At corrected threshold, PMS showed decreased intra- and inter-thalamic RS FC, and increased RS FC between the thalamus and the hippocampus, bilaterally. At uncorrected threshold, decreased thalamic RS FC with caudate nucleus, cerebellum and anterior cingulate cortex (ACC), as well as increased thalamic RS FC with occipital regions, were also detected. Lower CRF, measured as peak oxygen consumption (VO_2peak), correlated with lower white matter volume (r = 0.31, p = 0.03). Moreover, lower levels of light PA correlated with increased thalamic RS FC with the right hippocampus (r = - 0.3, p = 0.05).

DISCUSSION

People with PMS showed widespread brain atrophy, as well as pronounced intra-thalamic and thalamo-hippocampal RS FC abnormalities. White matter atrophy correlated with CRF, while increased thalamo-hippocampal RS FC was associated to worse PA levels. Thalamic RS FC might be used to monitor physical impairment and efficacy of rehabilitative and disease-modifying treatments in future studies.