Fatigue and Mobility Post-Stroke

Fatigue post-stroke is a disabling and persistent symptom affecting many stroke survivors. Despite its high prevalence, the pathophysiology underlying this phenomenon remains obscure. Thus, the aim of this thesis was to study the neuromuscular basis underlying fatigue post-stroke and its association with self-reported fatigue and with the performance of tasks incorporating balance and mobility components. Community-dwelling stroke survivors who had mild to moderate deficits in functional balance and mobility participated in a series of investigations. Chapter 2 describes the initial validation of the Community Balance and Mobility (CB&M) scale for use in persons with chronic stroke. Chapter 3 reported the presence of self-reported fatigue, assessed with the Fatigue Assessment Scale and restricted functional balance and mobility, measured with the 6-minute walk test and with the CB&M. Based on the findings obtained from the twitch interpolation and transcranial magnetic stimulation techniques, stroke resulted in a shift of the origin of neuromuscular fatigue such that the participants with stroke were more susceptible to the development of central fatigue following a standardized fatigue task, whereas healthy subjects had more evidence of peripheral fatigue. Also, the results from Chapter 3 demonstrated that the susceptibility to central failure was positively associated with the increased self-reported fatigability and negatively with the 6-MWT and CB&M scores. In Chapter 4 changes in the intrinsic properties of the spinal motoneurons, manifested as prolongation of the afterhyperpolarization time-course estimated with the interval death rate transform method were demonstrated. Prolonged afterhyperpolarization may have contributed to the increased central fatigue observed on the paretic side of the participants with stroke. In summary, the stroke-induced disturbances along the neuromuscular system together with the post-stroke deficits in functional balance and mobility may compromise the ability of the central nervous system to cope with the increased physiological demands during physical activities. This may lead to the increased perception of effort, which could influence the performance of activities of daily living and may partially underlie the general complaint of fatigue experienced by people with stroke. The findings reported in this thesis have advanced the understanding of a pathophysiological basis of fatigue post-stroke, which is essential for developing and guiding effective rehabilitation treatments

Does perturbation-based balance training prevent falls? Systematic review and meta-analysis of preliminary randomized controlled trials

Background: Older adults and individuals with neurological conditions are at an increased risk for falls. While physical exercise can prevent falls, certain types of exercise may be more effective. Perturbation-based balance training is a novel intervention involving repeated postural perturbations aiming to improve control of rapid balance reactions. Purpose: To estimate the effect of perturbation-based balance training on falls in daily life. Data sources: Medline (1946-July 2014), EMBASE (1974-July 2014), PEDro (all dates), CENTRAL (1991-July 2014) and Google Scholar (all dates). Study selection: Randomized controlled trials written in English were included if they focused on perturbation-based balance training among older adults or individuals with neurological conditions and collected falls data post-training. Data extraction: Two investigators extracted data independently. Study authors were contacted to obtain missing information. A PEDro score was obtained for each study. Primary outcomes were proportion of participants who reported one or more falls (i.e., number of fallers) and the total number of falls. The risk ratio (proportion of fallers) and rate ratio (number of falls) were entered into the analysis. Data synthesis: Eight studies involving 404 participants were included. Participants who completed perturbation-based balance training were less likely to report a fall (overall risk ratio 0.71, 95% confidence interval [0.52, 0.96]; p=0.02) and reported fewer falls than those in the control groups (overall rate ratio 0.54, 95% confidence interval [0.34, 0.85]; p=0.007). Limitations: Study authors do not always identify that they have included perturbation training in their intervention; therefore, it is possible that some appropriate studies were not included. Study designs were heterogeneous preventing sub-analyses. Conclusions: Perturbation-based balance training appears to reduce fall risk among older adults and individuals with Parkinson’s disease.KP was supported by a Focus on Stroke personnel award from the Heart and Stroke Foundation and the Canadian Stroke Network. We thank Jessica Babineau, BA MLIS, for her assistance with the literature search

Promoting Optimal Physical Exercise for Life: An Exercise and Self-Management Program to Encourage Participation in Physical Activity after Discharge from Stroke Rehabilitation—A Feasibility Study

People with stroke do not achieve adequate levels of physical exercise following discharge from rehabilitation. We developed a group exercise and self-management program (PROPEL), delivered during stroke rehabilitation, to promote uptake of physical activity after discharge. This study aimed to establish the feasibility of a larger study to evaluate the effect of this program on participation in self-directed physical activity. Participants with subacute stroke were recruited at discharge from one of three rehabilitation hospitals; one hospital offered the PROPEL program whereas the other two did not (comparison group; COMP). A high proportion (11/16) of eligible PROPEL program participants consented to the study. Fifteen COMP participants were also recruited. Compliance with wearing an accelerometer for 6 weeks continuously and completing physical activity questionnaires was high (>80%), whereas only 34% of daily heart rate data were available. Individuals who completed the PROPEL program seemed to have higher outcome expectations for exercise, fewer barriers to physical activity, and higher participation in physical activity than COMP participants (Hedge’s g≥0.5). The PROPEL program delivered during stroke rehabilitation shows promise for reducing barriers to exercise and increasing participation in physical activity after discharge. This study supports feasibility of a larger randomized trial to evaluate this program

Promoting Optimal Physical Exercise for Life: An Exercise and Self-Management Program to Encourage Participation in Physical Activity after Discharge from Stroke Rehabilitation—A Feasibility Study

People with stroke do not achieve adequate levels of physical exercise following discharge from rehabilitation. We developed a group exercise and self-management program (PROPEL), delivered during stroke rehabilitation, to promote uptake of physical activity after discharge. This study aimed to establish the feasibility of a larger study to evaluate the effect of this program on participation in self-directed physical activity. Participants with subacute stroke were recruited at discharge from one of three rehabilitation hospitals; one hospital offered the PROPEL program whereas the other two did not (comparison group; COMP). A high proportion (11/16) of eligible PROPEL program participants consented to the study. Fifteen COMP participants were also recruited. Compliance with wearing an accelerometer for 6 weeks continuously and completing physical activity questionnaires was high (>80%), whereas only 34% of daily heart rate data were available. Individuals who completed the PROPEL program seemed to have higher outcome expectations for exercise, fewer barriers to physical activity, and higher participation in physical activity than COMP participants (Hedge’s ). The PROPEL program delivered during stroke rehabilitation shows promise for reducing barriers to exercise and increasing participation in physical activity after discharge. This study supports feasibility of a larger randomized trial to evaluate this program.Peer Reviewe

Use of Accelerometer-Based Feedback of Walking Activity for Appraising Progress With Walking-Related Goals in Inpatient Stroke Rehabilitation: A Randomized Controlled Trial

Trial registration: ClinicalTrials.gov NCT01521234Background: Regaining independent ambulation is important to those with stroke. Increased walking practice during ‘down time’ in rehabilitation could improve walking function for individuals with stroke. Objective: To determine the effect of providing physiotherapists with accelerometer-based feedback on patient activity and walking-related goals during in-patient stroke rehabilitation. Methods: Participants with stroke wore accelerometers around both ankles every weekday during in-patient rehabilitation. Participants were randomly assigned to receive daily feedback about walking activity via their physiotherapists (n=29) or to receive no feedback (n=28). Changes in measures of daily walking (walking time, number of steps, average cadence, longest bout duration, and number of ‘long’ walking bouts) and changes in gait control and function assessed in-laboratory were compared between groups. Results: There was no significant increase in walking time, number of steps, longest bout duration, or number of long walking bouts for the feedback group compared to the control group (p-values>0.20). However, individuals who received feedback significantly increased cadence of daily walking than the control group (p=0.013). From the in-laboratory gait assessment, individuals who received feedback had a greater increase in walking speed and decrease in step time variability than the control group (p-values<0.030). Conclusion: Feedback did not increase the amount of walking completed by individuals with stroke. However, there was a significant increase in cadence, indicating that intensity of daily walking was greater for those who received feedback than the control group. Additionally, more intense daily walking activity appeared to translate to greater improvements in walking speed.This project was generously funded by a grant from the Ontario Ministry of Health and Long-Term Care, administered and supported by the Ontario Stroke Network (OSN1101-000149). Equipment and space have been funded with grants from the Canada Foundation for Innovation, Ontario Innovation Trust, and the Ministry of Research and Innovation. At the time of this study, Elizabeth Inness was supported by a Canadian Institutes of Health Research fellowship. The views expressed do not necessarily reflect those of the funders

Perturbation training to promote safe independent mobility post-stroke: study protocol for a randomized controlled trial

Abstract Background Falls are one of the most common medical complications post-stroke. Physical exercise, particularly exercise that challenges balance, reduces the risk of falls among healthy and frail older adults. However, exercise has not proven effective for preventing falls post-stroke. Falls ultimately occur when an individual fails to recover from a loss of balance. Thus, training to specifically improve reactive balance control could prevent falls. Perturbation training aims to improve reactive balance control by repeatedly exposing participants to postural perturbations. There is emerging evidence that perturbation training reduces fall rates among individuals with neurological conditions, such as Parkinson disease. The primary aim of this work is to determine if perturbation-based balance training can reduce occurrence of falls in daily life among individuals with chronic stroke. Secondary objectives are to determine the effect of perturbation training on balance confidence and activity restriction, and functional balance and mobility. Methods/design Individuals with chronic stroke will be recruited. Participants will be randomly assigned to one of two groups: 1) perturbation training, or 2) ‘traditional’ balance training. Perturbation training will involve both manual perturbations (e.g., a push or pull from a physiotherapist), and rapid voluntary movements to cause a loss of balance. Training will occur twice per week for 6 weeks. Participants will record falls and activity for 12 months following completion of the training program. Standardized clinical tools will be used to assess functional balance and mobility, and balance confidence before and after training. Discussion Falls are a significant problem for those with stroke. Despite the large body of work demonstrating effective interventions, such as exercise, for preventing falls in other populations, there is little evidence for interventions that prevent falls post-stroke. The proposed study will investigate a novel and promising intervention: perturbation training. If effective, this training has the potential to not only prevent falls, but to also improve safe independent mobility and engagement in daily activities for those with stroke. Trial registration Current Controlled Trials: ISRCTN05434601