Information processing speed and disease severity predict real-world ambulation in persons with multiple sclerosis

BACKGROUND

Impairments in real-world gait quality and quantity are multifaceted for individuals with multiple sclerosis (MS), encompassing mobility, cognition, and fear of falling. However, these factors are often examined independently, limiting insights into the combined contributions they make to real-world ambulation.

RESEARCH QUESTION

How do mobility, cognition, and fear of falling contribute to real-world gait quality and quantity in individuals with MS?

METHODS

Twenty individuals with MS underwent a series of cognitive assessments, including the Paced Auditory Serial Addition Test (PASAT), Symbol Digits Modalities Test (SDMT), Stroop Test, and the Selective Reminding Test (SRT). Participants also completed the Falls Efficacy Scale - International (FES-I) and walking impairment using the Patient Determined Disease Steps (PDDS). Following the in-lab session, participants wore an inertial sensor on their lower back and asked to go about their typical daily routines for three days. Metrics of gait speed, stride regularity, time spent walking, and total bouts were extracted from the real-world data.

RESULTS

Significant correlations were found between both real-world gait speed and stride regularity and the SDMT, FES-I, and PDDS. Backward linear regression analysis was conducted for gait speed and stride regularity, with PDDS and SDMT included in the final model for both metrics. These variables explained 63% of the variance in gait speed and 69% of the variance in stride regularity. Results were not significant for gait quantity after adjusting for age and sex.

SIGNIFICANCE

The study's results provide insight regarding the roles of cognition, walking impairment, and fear of falling on real-world ambulation. Deeper understanding of these contributions can inform the development of targeted interventions that aim to improve walking. Additionally, the absence of significant correlations between gait metrics, cognition, and fear of falling with gait quantity underscores the need for further research to identify factors that increased walking in this population.

Mobility and Dual Tasking in the Everyday Lives of Adults with Multiple Sclerosis: A Qualitative Exploration

OBJECTIVE

The purpose of the study was to understand how people with multiple sclerosis experience dual-tasking situations in their everyday lives.

METHODS

Focus groups involving a total of 11 individuals with multiple sclerosis (eight females and three males) participated in this qualitative inquiry. Participants were asked open-ended questions focused on the nature of and consequences around dual tasking when standing or walking. Reflexive thematic analysis was employed to examine the data.

RESULTS

Three themes were generated from the data: (a) Life Is a Dual Task, (b) The Social Divide, and (c) Sacrifices for Stability.

CONCLUSIONS

This study highlights the significance and impact of dual tasking on the lived experience of adults with multiple sclerosis, furthering the need to more fully examine this phenomenon and potentially improve fall-prevention interventions and facilitate community participation.

An Exploratory Study of Community Mobility in Adults With Multiple Sclerosis Across Different Ambulation Levels

BACKGROUND

The purpose of this study was to identify differences in community mobility in adults with multiple sclerosis (MS) at various ambulation levels.

METHODS

Seventy-one adults with MS completed a survey about their mobility impairment and avoidance of challenging mobility tasks. Individuals were categorized as having mild, moderate, or severe gait impairment.

RESULTS

Participants across the different functional groups significantly differed in perceived ambulation disability, fatigue impact, falls efficacy, quality of life, challenges with dual-tasking, and self-efficacy for community mobility. There were no significant differences between the mild and moderate gait impairment groups in crossing a busy street or going out in different ambient conditions. Significant differences were found between those with mild impairment and those with severe impairment in avoidance of various terrain elements, heavy manual doors, postural transitions, attentional situations, and crowded places. The only environmental dimension that significantly differed across all 3 groups was carrying 2 or more items, in which avoidance increased as ambulation worsened.

CONCLUSIONS

Avoidance behavior for particular environmental features can begin relatively early in the disease process. This underscores the need to further study mobility differences, community ambulation, and participation restrictions in adults with MS.

High intensity exercise training on functional outcomes in persons with multiple sclerosis: A systematic review

BACKGROUND

There is growing interest and evidence for high intensity training (HIT) in clinical populations, including persons with multiple sclerosis (MS). While HIT has been shown to be a safe modality in this group, it is still unclear what collective knowledge exists for HIT on functional outcomes. This study examined HIT modalities (e.g., aerobic, resistance, functional training) on functional outcomes such as walking, balance, postural control, and mobility in persons with MS.

METHODS

High intensity training studies, including RCTs and non-RCTs, that targeted functional outcomes in persons with MS were included in the review. A literature search was conducted in MEDLINE, EMBASE, PsycINFO, SPORTSDiscus, and CINAHL in April 2022. Other literature search methods were performed via website and citation searching. The methodological quality of included studies was assessed by TESTEX for RCTs and ROBINS-I for non-RCTs. This review synthesized the following data: study design and characteristics, participant characteristics, intervention characteristics, outcome measures, and effect sizes.

RESULTS

Thirteen studies (6 RCTs and 7 non-RCTs) were included in the systematic review. The included participants (N = 375) had varying functional levels (EDSS range: 0-6.5) and phenotypes (relapsing remitting, secondary progressive, primary progressive). HIT modalities involving high intensity aerobic training (n = 4), high intensity resistance training (n = 7), and high intensity functional training (n = 2), revealed a significant and consistent benefit on walking speed and walking endurance in response to HIT, while the evidence regarding balance and mobility improvement was less clear.

CONCLUSION

Persons with MS can successfully tolerate and adhere to HIT. While HIT appears to be an effective modality for improving some functional outcomes, the heterogeneous testing protocols, HIT modalities, and exercise doses among the studies preclude any conclusive evidence for its effectiveness thus necessitating future inquiry.

Predicting falls in adults with multiple sclerosis using patient-reported measures: Are perceptions of dual-tasking missing?

BACKGROUND

Mobility challenges and cognitive impairments prominent in adults with multiple sclerosis (MS) significantly increase the risk of falling. Examining perceptions of how the simultaneous performance of completing motor and cognitive tasks impacts fall risk may have clinical utility. The purpose of this study was to identify the most significant self-reported predictors of falling including perceived dual-tasking.

METHODS

Participants included 79 individuals with MS were surveyed and reported their fall history over the previous 3 months and completed the Multiple Sclerosis Walking Scale -12 (MSWS-12), Modified Fatigue Impact Scale (MFIS), Falls Efficacy Scale International (FES-I), and two Dual-Task Questionnaires (DTQ), a previously published original one and a newly expanded version.

RESULTS

Of the sample, 63 were classified as non-fallers and 16 as fallers. Backward stepwise regression analysis revealed that perceived ambulation disability and dual-tasking best predicted fall status (sensitivity of 57.7%, specificity of 90.6%, area under the receiving operating curve of 0.81 (95% CI 0.70-0.92).

CONCLUSION

The inclusion of self-reported dual-tasking perceptions has utility in predicting fall risk. Effective assessment toward this end offers the potential for early detection and intervention.

Acute effects of axial loading on postural control during walking and turning in people with multiple sclerosis: A pilot study

BACKGROUND

Impaired sensory integration is heavily involved in gait control and accentuates fall risk in individuals with multiple sclerosis (MS). While axial loading has been found beneficial, little is known about the effect of non-specific axial loads on gait parameters and mobility tasks in those with MS.

RESEARCH QUESTION

What are the effects of non-specific axial loading via weighted vests on walking and turning in those with MS.

METHODS

Twelve participants with MS and eleven age- and gender-matched healthy controls participated in a cross-sectional study. All participants completed five trials of continuous walking with turns wearing weighted vests at 0%, 2%, 4%, 5%, and then 0% of their body weight. Gait parameters were measured using wireless inertial sensors. A 2 (group) x 5 (vest weight) multivariate analysis of variance (MANOVA) was performed to determine any significant differences between groups and across weighted vests for each gait variable. Post-hoc analysis and paired t-tests with corresponding effect sizes were also conducted.

RESULTS

A significant between groups main effect was found for group (F (6100) = 14.74, p = .000) in multiple gait parameters (p < 0.05), although no significant main effect was found for weighted vest. Within group analyses indicated significantly increased cadence and gait speed across varying weighted vests for both MS and control groups (p < 0 >05). Increased vest weight from 0%PRE to 2% also had large effect on shortening double support time and increasing stride length in the MS group.

SIGNIFICANCE

This study provided preliminary evidence that non-specific axial loads of varying weights appear to improve certain gait parameters. As such, this modality may offer mobility benefit and serve as an accessible home-based intervention alternative aimed at improving walking in individuals with MS.

Motivation for Physical Activity in Adults with Multiple Sclerosis: A Self-determination Theory–Based Approach

Background: Despite the benefits of regular physical activity (PA), most adults with multiple sclerosis (MS) are insufficiently active. Identifying the motivational correlates of PA is necessary to facilitate health behavior change. The extent to which the constructs of psychological need satisfaction and motivational regulations associate with self-determined PA in adults with the disease was examined.

Methods: Individuals with MS were provided a link to a web-based survey. There were 290 respondents: 242 women and 48 men aged 22 to 71 (mean ± SD, 49.50 ± 12.05) years with primarily mild-to-moderate mobility impairment who completed the Psychological Need Satisfaction in Exercise scale, the Behavioral Regulation in Exercise Questionnaire, and the International Physical Activity Questionnaire.

Results: Path analysis revealed that PA was best predicted by integrated regulation, competence, and mobility, explaining 28% of the variance in PA behavior. All three need satisfaction variables (relatedness, competence, and autonomy) and mobility impairment accounted for 43% of the variance in integrated regulation.

Conclusions: Increasing satisfaction of the need for relatedness, competence, and autonomy can lead to more integrated and internally motivated PA engagement in adults with MS.

A Preliminary Investigation of the Effects of Obstacle Negotiation and Turning on Gait Variability in Adults with Multiple Sclerosis

Many falls in persons with multiple sclerosis (PwMS) occur during daily activities such as negotiating obstacles or changing direction. While increased gait variability is a robust biomarker of fall risk in PwMS, gait variability in more ecologically related tasks is unclear. Here, the effects of turning and negotiating an obstacle on gait variability in PwMS were investigated. PwMS and matched healthy controls were instrumented with inertial measurement units on the feet, lumbar, and torso. Subjects completed a walk and turn (WT) with and without an obstacle crossing (OW). Each task was partitioned into pre-turn, post-turn, pre-obstacle, and post-obstacle phases for analysis. Spatial and temporal gait measures and measures of trunk rotation were captured for each phase of each task. In the WT condition, PwMS demonstrated significantly more variability in lumbar and trunk yaw range of motion and rate, lateral foot deviation, cadence, and step time after turning than before. In the OW condition, PwMS demonstrated significantly more variability in both spatial and temporal gait parameters in obstacle approach after turning compared to before turning. No significant differences in gait variability were observed after negotiating an obstacle, regardless of turning or not. Results suggest that the context of gait variability measurement is important. The increased number of variables impacted from turning and the influence of turning on obstacle negotiation suggest that varying tasks must be considered together rather than in isolation to obtain an informed understanding of gait variability that more closely resembles everyday walking.

The role of resilience: Physical activity continuation after falling in adults with multiple sclerosis

BACKGROUND

As activity curtailment is common after a fall, the ability to harness resiliency is particularly salient for those with multiple sclerosis (MS) who fall frequently and who significantly benefit from remaining physically active.

OBJECTIVE

The purpose of the study was to identify resilience factors, coping processes, and benefit finding underscoring the continuation of physical activity after experiencing a fall in individuals with MS.

METHODS

Twelve individuals with MS (seven females and five males) participated in this qualitative study. Participants were asked general questions regarding their physical activity engagement and experiences around falling. Specific questions focused on health perceptions, personal characteristics, strategies and behaviors employed after a fall that related to remaining physically active, and any positives they perceived from falling. Transcribed interviews were analyzed and semantic themes identified.

RESULTS

From the data, specific protective factors, resilience processes, and benefit finding emerged to explain participant capability to bounce back and continue with physical activity after falling. These personal factors included Locus of Control, Perseverance, Positive Attitude and Optimism, and Flexibility. Resilience processes included Utilizing Support, Problem Based Coping, and Perspective Taking. Finally, the theme of Looking Beyond Oneself was identified as a benefit.

CONCLUSIONS

Understanding existing resilience factors that allow an individual to remain physically active after falling can potentially inform resilience-building interventions that broaden and build resilience resources and improve psychological and physical health in those with MS.

Using Body-Worn Sensors to Detect Changes in Balance and Mobility After Acute Aerobic Exercise in Adults with Multiple Sclerosis

Background

Current mobility and functional assessments do not capture the subtle changes in balance and gait that may predispose people with multiple sclerosis (MS) to falling. The purpose of this study was to use clinical and instrumented measures to examine the effects of an acute bout of aerobic exercise on balance and gait in individuals with MS.

Methods

Ten adults with MS performed 15 minutes of moderate-intensity recumbent cycling or 15 minutes of rest. Exercise and rest visit order was randomized and separated by 1 week. Balance and mobility were assessed before, immediately after, and 2 hours after each test condition.

Results

There were no significant differences across measurement periods for Timed 25-Foot Walk test times or Brief Balance Evaluation Systems Test scores. Significant improvements in mean sway radius and sway velocity when standing on foam and in percentage of stance stride time variability were found immediately after exercise compared with immediately after rest.

Conclusions

This study lends further evidence that individuals with MS can safely engage in single bouts of aerobic exercise without detrimental short-term effects on function and may actually receive some short-term benefit regarding standing postural sway and gait variability. Future research should examine the dose-dependent relationship of varying types, intensities, or timing of exercise necessary to elicit short-term functional benefit and long-term health outcomes.

Social Cognitive Factors, Physical Activity, and Mobility Impairment in Adults with Multiple Sclerosis

Among those with multiple sclerosis (MS), mobility impairment is common and significantly affects independent functioning and quality of life. The purpose of the study was to examine the role of physical activity in mobility impairment in individuals with MS and explore the social cognitive factors of social support, outcome expectations, and self-efficacy that facilitate physical activity among those with the disease. A sample of 319 individuals with MS were assessed on the following: family and friend social support, self-efficacy, and physical and social outcome expectations. Self-reported physical activity, perceived ambulation disability, balance confidence, and fall history were also measured. The structural model fit the data (χ² (29) = 24.49, p = 0.70; Root Mean Square Error of Approximation < 0.01; Comparative Fit Index = 1.0; Normed Fit Index = 0.96; Goodness of Fit Index = 0.98; Standardized Root Mean Square Residual = 0.03). The primary findings of the study revealed that physical activity was strongly linked to mobility impairment (path coefficient, -0.43), such that increasing levels of physical activity were associated with less mobility impairment. The most important predictors of health-promoting levels of physical activity were self-efficacy (path coefficient, 0.48) and social support (path coefficient, 0.38), with support from friends being a stronger indicator of social support than support from family. It may be prudent to design interventions aimed at increasing physical activity, especially in regard to helping individuals become more efficacious and building larger social networks, as this may serve to forestall advancing mobility impairment in those with MS.

Symptom variability, affect and physical activity in ambulatory persons with multiple sclerosis: Understanding patterns and time-bound relationships

BACKGROUND

Individuals with multiple sclerosis (MS) experience a clinical course that is highly variable with daily fluctuations in symptoms significantly affecting functional ability and quality of life. Yet, understanding how MS symptoms co-vary and associate with physical and psychological health is unclear.

OBJECTIVE

The purpose of the study was to explore variability patterns and time-bound relationships across symptoms, affect, and physical activity in individuals with MS.

METHODS

The study employed a multivariate, replicated, single-subject repeated-measures (MRSRM) design and involved four individuals with MS. Mood, fatigue, pain, balance confidence, and losses of balance were measured daily over 28 days by self-report. Physical activity was also measured daily over this same time period via accelerometry. Dynamic factor analysis (DFA) was used to determine the dimensionality and lagged relationships across the variables.

RESULTS

Person-specific models revealed considerable time-dependent co-variation patterns as well as pattern variation across subjects. Results also offered insight into distinct variability structures at varying levels of disability.

CONCLUSION

Modeling person-level variability may be beneficial for addressing the heterogeneity of experiences in individuals with MS and for understanding temporal and dynamic interrelationships among perceived symptoms, affect, and health outcomes in this group.

Balance impairment in people with multiple sclerosis: preliminary evidence for the Balance Evaluation Systems Test

This study examined the validity of the Balance Evaluation Systems Test (BESTest) to identify balance impairments in people with multiple sclerosis (MS) by evaluating differences in BESTest performance between people with and without MS. We also assessed the BESTest's validity by correlation with objective measures of postural performance as well as with disease severity and fall status. Thirteen subjects with MS (Expanded Disability Status Scale; EDSS: 0-4.5) and 13 matched subjects without MS were evaluated on the BESTest, asked about fall history, and assessed by force plates and motion capture as they performed laboratory tasks of step initiation, forward leaning to the limits of stability, and postural responses to rotations of the support surface. Compared to subjects without MS, subjects with MS exhibited lower total BESTest scores (mean (95%) score for subjects with MS=91 (83-99); subjects without MS=105 (104-107)) as well as section scores pertaining to mechanical constraints, limits of stability, anticipatory postural adjustments, and gait. BESTest scores significantly correlated with objective laboratory measures of step velocity during step initiation (Pearson r(2)=0.48, P<0.01) as well as center-of-pressure displacements during both the leaning (Pearson r(2)=0.55, P<0.005) and postural-response tasks (Pearson r(2)=0.76, P<0.0001). BESTest total scores were 92% accurate to identify fallers and non-fallers, and BESTest scores significantly correlated with EDSS scores (Spearman's rho=0.85, P<0.0005). Thus, the BESTest provides a valid clinical assessment of balance impairments in people with MS.

Variability in constraints and functional competence in adults with multiple sclerosis

OBJECTIVE

Examine intraindividual change in physical and psychological impairments associated with multiple sclerosis and assess the relationship between changes in specific deficits and functional competence in activities of daily living.

DESIGN

A multivariate, replicated, single-subject, repeated-measures design was used to examine variability patterns across subjects. Five adults with multiple sclerosis were assessed on leg strength, upright postural control, mood, fatigue, stress, and self-efficacy for 4 mo. Functional competence in three activities of daily living was also evaluated. P-technique factor analyses were performed to examine which variables covaried with time.

RESULTS

Analyses revealed covariation among physical and psychological variables for four of the five participants. Across all participants, coefficients of variation revealed greater variability in stress (32.3%-53.4%) and fatigue (23.4%-5.9%) than in any of the physical variables (<20%), and variability in all impairments was greater than variability in the functional tasks (0%-12.6%).

CONCLUSIONS

The greater stability in functional performance compared with both physical and psychological constraints provides important insight into symptom management and clinical intervention. The magnitude of variability found in the psychological variables across individuals also has implications concerning psychological adjustment to the disease.