Capturing ambulatory activity decline in Parkinson's disease

Optimizing Clinical Assessments in Parkinson's Disease Through the Use of Wearable Sensors and Data Driven Modeling

The emergence of motion sensors as a tool that provides objective motor performance data on individuals afflicted with Parkinson's disease offers an opportunity to expand the horizon of clinical care for this neurodegenerative condition. Subjective clinical scales and patient based motor diaries have limited clinometric properties and produce a glimpse rather than continuous real time perspective into motor disability. Furthermore, the expansion of machine learn algorithms is yielding novel classification and probabilistic clinical models that stand to change existing treatment paradigms, refine the application of advance therapeutics, and may facilitate the development and testing of disease modifying agents for this disease. We review the use of inertial sensors and machine learning algorithms in Parkinson's disease.

Accuracy of Activity Trackers in Parkinson Disease: Should We Prescribe Them?

BACKGROUND

Wearable, consumer-grade activity trackers have become widely available as a means of monitoring physical activity in the form of step counts. However, step counts may not be accurate in persons with Parkinson disease (PD) due to atypical gait characteristics.

OBJECTIVE

This study aimed to investigate the accuracy of 4 consumer-grade activity trackers in individuals with PD while ambulating during continuous and discontinuous walking tasks.

DESIGN

This study used a cross-sectional design.

METHODS

Thirty-three persons with PD (Hoehn & Yahr stages 1-3) donned 4 models of activity trackers on the less affected side of their bodies. Participants performed 2 continuous walking tasks (2-minute walk tests at comfortable and fast speeds) and 2 discontinuous walking tasks (a simulated household course and an obstacle negotiation course) in an outpatient setting. Bland-Altman plots and intraclass correlation coefficients [ICC(2,1)] were computed as a measure of agreement between actual steps taken (reference standard: video recording) and steps recorded by each tracker.

RESULTS

The accuracy of the activity trackers varied widely, with ICCs ranging from -0.03 to 0.98. Overall, the most accurate device across all tasks was the Fitbit Zip, and the least accurate was the Jawbone Up Move during the simulated household course. All activity trackers were more accurate for continuous walking tasks compared with discontinuous walking tasks. Waist-mounted devices were more accurate than wrist-mounted devices with continuous tasks. Bland-Altman plots revealed that all activity trackers underestimated step counts.

LIMITATIONS

All walking tasks were measured over relatively short distances.

CONCLUSIONS

In persons with mild-to-moderate PD, waist-worn activity trackers may be prescribed to monitor bouts of continuous walking with reasonable accuracy; however, activity trackers have little utility in monitoring discontinuous walking common in household settings.

Prática mental após fisioterapia mantém mobilidade funcional de pessoas com doença de Parkinson

RESUMO O objetivo deste estudo foi avaliar a prática mental após a fisioterapia motora para manutenção dos efeitos obtidos na mobilidade funcional de pessoas com doença de Parkinson (DP). Este ensaio clínico randomizado controlado, com cegamento simples, incluiu 14 sujeitos com DP nos estágios de 1 a 3 (escala de Hoehn & Yahr), com idade entre 45 e 72 anos. Após a avaliação inicial com o Timed Up & Go (TUG), Dynamic Gait Index (DGI) e Falls Efficacy Scale - International Brazil (FES-I Brasil), os sujeitos realizaram 15 sessões de fisioterapia motora. Foram reavaliados e divididos randomicamente em Grupo Controle (GC) e Grupo Prática Mental (GPM). Após a alocação, o GPM foi submetido a 10 sessões de prática mental associada a orientações de exercícios domiciliares. O GC foi orientado apenas a realizar os exercícios domiciliares. Em seguida, os grupos foram novamente reavaliados. Verificou-se que o GPM continuou apresentando redução na média de tempo do TUG na segunda reavaliação (p=0,05). Na segunda reavaliação do DGI, o GPM manteve a mesma média de escore da primeira reavaliação e o GC apresentou declínio da média. Não foram verificadas diferenças significativas na comparação intergrupos dos escores na FES-I Brasil. A prática mental foi capaz de manter os ganhos obtidos pela fisioterapia na mobilidade funcional de pacientes com DP.

Peer Coaching Through mHealth Targeting Physical Activity in People With Parkinson Disease: Feasibility Study

Background

Long-term engagement in exercise and physical activity mitigates the progression of disability and increases quality of life in people with Parkinson disease (PD). Despite this, the vast majority of individuals with PD are sedentary. There is a critical need for a feasible, safe, acceptable, and effective method to assist those with PD to engage in active lifestyles. Peer coaching through mobile health (mHealth) may be a viable approach.

Objective

The purpose of this study was to develop a PD-specific peer coach training program and a remote peer-mentored walking program using mHealth technology with the goal of increasing physical activity in persons with PD. We set out to examine the feasibility, safety, and acceptability of the programs along with preliminary evidence of individual-level changes in walking activity, self-efficacy, and disability in the peer mentees.

Methods

A peer coach training program and a remote peer-mentored walking program using mHealth was developed and tested in 10 individuals with PD. We matched physically active persons with PD (peer coaches) with sedentary persons with PD (peer mentees), resulting in 5 dyads. Using both Web-based and in-person delivery methods, we trained the peer coaches in basic knowledge of PD, exercise, active listening, and motivational interviewing. Peer coaches and mentees wore FitBit Zip activity trackers and participated in daily walking over 8 weeks. Peer dyads interacted daily via the FitBit friends mobile app and weekly via telephone calls. Feasibility was determined by examining recruitment, participation, and retention rates. Safety was assessed by monitoring adverse events during the study period. Acceptability was assessed via satisfaction surveys. Individual-level changes in physical activity were examined relative to clinically important differences.

Results

Four out of the 5 peer pairs used the FitBit activity tracker and friends function without difficulty. A total of 4 of the 5 pairs completed the 8 weekly phone conversations. There were no adverse events over the course of the study. All peer coaches were “satisfied” or “very satisfied” with the training program, and all participants were “satisfied” or “very satisfied” with the peer-mentored walking program. All participants would recommend this program to others with PD. Increases in average steps per day exceeding the clinically important difference occurred in 4 out of the 5 mentees.

Conclusions

Remote peer coaching using mHealth is feasible, safe, and acceptable for persons with PD. Peer coaching using mHealth technology may be a viable method to increase physical activity in individuals with PD. Larger controlled trials are necessary to examine the effectiveness of this approach.

Wearable sensors for clinical applications in epilepsy, Parkinson's disease, and stroke: a mixed-methods systematic review

OBJECTIVES

Wearable technology is increasingly used to monitor neurological disorders. The purpose of this systematic review was to synthesize knowledge from quantitative and qualitative clinical researches using wearable sensors in epilepsy, Parkinson's disease (PD), and stroke.

METHODS

A systematic literature search was conducted in PubMed and Scopus spanning from 1995 to January 2017. A synthesis of the main findings, reported adherence to wearables and missing data from quantitative studies, is provided. Clinimetric properties of measures derived from wearables in laboratory, free activities in hospital, and free-living environment were also evaluated. Qualitative thematic synthesis was conducted to explore user experiences and acceptance of wearables.

RESULTS

In total, 56 studies (50 reporting quantitative and 6 reporting qualitative data) were included for data extraction and synthesis. Among studies reporting quantitative data, 5 were in epilepsy, 21 PD, and 24 studies in stroke. In epilepsy, wearables are used to detect and differentiate seizures in hospital settings. In PD, the focus is on quantification of cardinal motor symptoms and medication-evoked adverse symptoms in both laboratory and free-living environment. In stroke upper extremity activity, walking and physical activity have been studied in laboratory and during free activities. Three analytic themes emerged from thematic synthesis of studies reporting qualitative data: acceptable integration in daily life, lack of confidence in technology, and the need to consider individualization.

CONCLUSIONS

Wearables may provide information of clinical features of interest in epilepsy, PD and stroke, but knowledge regarding the clinical utility for supporting clinical decision making remains to be established.

Obtaining Reliable Estimates of Ambulatory Physical Activity in People with Parkinson's Disease

We determined the number of days required, and whether to include weekdays and/or weekends, to obtain reliable measures of ambulatory physical activity in people with Parkinson's disease (PD). Ninety-two persons with PD wore a step activity monitor for seven days. The number of days required to obtain a reliable estimate of daily activity was determined from the mean intraclass correlation (ICC2,1) for all possible combinations of 1-6 consecutive days of monitoring. Two days of monitoring were sufficient to obtain reliable daily activity estimates (ICC2,1 > 0.9). Amount (p = 0.03) but not intensity (p = 0.13) of ambulatory activity was greater on weekdays than weekends. Activity prescription based on amount rather than intensity may be more appropriate for people with PD.

Interval setting selection affects ambulatory activity outputs in children with cerebral palsy

INTRODUCTION

Accelerometer based devices have been widely used to assess the ambulatory activity of children with and without functional disabilities. Many researchers who utilize the StepWatch Activity Monitor (SAM) collect at a 60second (60sec) interval setting. The purpose of this study was to assess the effect of SAM interval settings on ambulatory activity outputs in children with cerebral palsy (CP) and typically developing youth.

METHODS

Participants wore a SAM which recorded the number of strides every 10seconds (10s) for one week. Raw 10s data was downsampled to combine strides into 60sec intervals. Strides were ensembled into walking bouts with the Intensity/Duration calculated as a percentage of Total Ambulatory Time (TAT).

RESULTS

Twenty-eight children with CP (14 boys; avg. 12 yrs. 4 mths.; GMFCS Level I n=4, Level II n=19, Level III n=5) completed testing and 28 age matched typically developing youth (14 boys; avg. 12 yrs. 6 mths.) were included. Using the 10sec interval, ∼80% of walking bouts in both groups were less than or equal to 60s. Data recorded at 60sec intervals had higher daily TAT but fewer walking bouts. In children with CP, daily steps were higher using the 60sec interval. At the Easy intensity, the 60sec interval reported an increased volume of Long duration walking, and it rarely identified any Moderate+ intensity activity.

CONCLUSIONS

60sec interval data overestimated low intensity and long duration ambulatory activity. It is imperative that investigators choose a finer interval setting (10sec) to maximize the detection of gait transitions and rest periods which are critical in describing community ambulation of patients with cerebral palsy.

Analysis of Correlation between an Accelerometer-Based Algorithm for Detecting Parkinsonian Gait and UPDRS Subscales

Background

Our group earlier developed a small monitoring device, which uses accelerometer measurements to accurately detect motor fluctuations in patients with Parkinson’s (On and Off state) based on an algorithm that characterizes gait through the frequency content of strides. To further validate the algorithm, we studied the correlation of its outputs with the motor section of the Unified Parkinson’s Disease Rating Scale part-III (UPDRS-III).

Method

Seventy-five patients suffering from Parkinson’s disease were asked to walk both in the Off and the On state while wearing the inertial sensor on the waist. Additionally, all patients were administered the motor section of the UPDRS in both motor phases. Tests were conducted at the patient’s home. Convergence between the algorithm and the scale was evaluated by using the Spearman’s correlation coefficient.

Results

Correlation with the UPDRS-III was moderate (rho −0.56; p < 0.001). Correlation between the algorithm outputs and the gait item in the UPDRS-III was good (rho −0.73; p < 0.001). The factorial analysis of the UPDRS-III has repeatedly shown that several of its items can be clustered under the so-called Factor 1: “axial function, balance, and gait.” The correlation between the algorithm outputs and this factor of the UPDRS-III was −0.67 (p < 0.01).

Conclusion

The correlation achieved by the algorithm with the UPDRS-III scale suggests that this algorithm might be a useful tool for monitoring patients with Parkinson’s disease and motor fluctuations.

Integration of technology-based outcome measures in clinical trials of Parkinson and other neurodegenerative diseases

INTRODUCTION

We sought to review the landscape of past, present, and future use of technology-based outcome measures (TOMs) in clinical trials of neurodegenerative disorders.

METHODS

We systematically reviewed PubMed and ClinicalTrials.gov for published and ongoing clinical trials in neurodegenerative disorders employing TOMs. In addition, medical directors of selected pharmaceutical companies were surveyed on their companies' ongoing efforts and future plans to integrate TOMs in clinical trials as primary, secondary, or exploratory endpoints.

RESULTS

We identified 164 published clinical trials indexed in PubMed that used TOMs as outcome measures in Parkinson disease (n = 132) or other neurodegenerative disorders (n = 32). The ClinicalTrials.gov search yielded 42 clinical trials using TOMs, representing 2.7% of ongoing trials. Sensor-based technology accounted for over 75% of TOMs applied. Gait and physical activity were the most common targeted domains. Within the next 5 years, 83% of surveyed pharmaceutical companies engaged in neurodegenerative disorders plan to deploy TOMs in clinical trials.

CONCLUSION

Although promising, TOMs are underutilized in clinical trials of neurodegenerative disorders. Validating relevant endpoints, standardizing measures and procedures, establishing a single platform for integration of data and algorithms from different devices, and facilitating regulatory approvals should advance TOMs integration into clinical trials.

From Disease to Health: Physical Therapy Health Promotion Practices for Secondary Prevention in Adult and Pediatric Neurologic Populations

BACKGROUND AND PURPOSE

Over the last decade there has been a substantial increase in efforts to better understand how targeted physical activity and exercise interventions can be used to minimize secondary consequences arising from neurological damage in both adult and pediatric populations. This article offers an overview of contemporary research that addresses mediators of functional and neuroplastic adaptations associated with physical activity and exercise. We emphasize the important role that physical therapists can play to increase participation and improve well-being in adults and children with neurological disorders. We further highlight potential strategies to foster translation of evidence-based findings for use by clinicians and consumers.

SUMMARY OF KEY POINTS

Engagement in physical activity can serve as a powerful promoter of health and well-being in adults and youth with neurologic disease, and has the potential to alter the course of disease processes. Physical therapists can play a key role in promoting fitness and wellness by encouraging active living, providing early diagnosis of disease and prescribing targeted activity interventions to improve fitness and participation, and helping individuals overcome personal and environmental barriers to an active lifestyle.

RECOMMENDATIONS FOR CLINICAL PRACTICE

Physical therapists must adopt a model of rehabilitation that emphasizes secondary prevention in adults and youth with neurologic diseases. Physical therapists have a unique role in developing forward-thinking approaches in using innovative health and wellness strategies to promote positive changes in activity and exercise behaviors.

Factors Associated With Ambulatory Activity in De Novo Parkinson Disease

BACKGROUND AND PURPOSE

Objective ambulatory activity during daily living has not been characterized for people with Parkinson disease prior to initiation of dopaminergic medication. Our goal was to characterize ambulatory activity based on average daily step count and examine determinants of step count in nonexercising people with de novo Parkinson disease.

METHODS

We analyzed baseline data from a randomized controlled trial, which excluded people performing regular endurance exercise. Of 128 eligible participants (mean ± SD = 64.3 ± 8.6 years), 113 had complete accelerometer data, which were used to determine daily step count. Multiple linear regression was used to identify factors associated with average daily step count over 10 days. Candidate explanatory variable categories were (1) demographics/anthropometrics, (2) Parkinson disease characteristics, (3) motor symptom severity, (4) nonmotor and behavioral characteristics, (5) comorbidities, and (6) cardiorespiratory fitness.

RESULTS

Average daily step count was 5362 ± 2890 steps per day. Five factors explained 24% of daily step count variability, with higher step count associated with higher cardiorespiratory fitness (10%), no fear/worry of falling (5%), lower motor severity examination score (4%), more recent time since Parkinson disease diagnosis (3%), and the presence of a cardiovascular condition (2%).

DISCUSSION AND CONCLUSIONS

Daily step count in nonexercising people recruited for this intervention trial with de novo Parkinson disease approached sedentary lifestyle levels. Further study is warranted for elucidating factors explaining ambulatory activity, particularly cardiorespiratory fitness, and fear/worry of falling. Clinicians should consider the costs and benefits of exercise and activity behavior interventions immediately after diagnosis of Parkinson disease to attenuate the health consequences of low daily step count.Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1, http://links.lww.com/JNPT/A170).

A Cross-sectional Analysis of the Characteristics of Individuals With Parkinson Disease Who Avoid Activities and Participation Due to Fear of Falling

BACKGROUND AND PURPOSE

Avoidance behavior can have deleterious consequences on health and quality of life for persons with Parkinson disease (PD); for this reason, it is important to identify potentially mitigable characteristics. We compared the characteristics of individuals with PD who exhibit fear of falling (FOF) avoidance behavior with those who do not.

METHODS

Fifty-nine participants with PD were classified as avoiders (n = 27) or nonavoiders (n = 32) by using the Fear of Falling Avoidance Behavior Questionnaire and compared across 5 domains: demographic characteristics; PD-specific symptoms (subtype, Movement Disorder Society-Unified Parkinson's Disease Rating Scale [MDS-UPDRS], Hoehn and Yahr Scale, Parkinson's Disease Questionnaire-39 [PDQ-39]); balance and falls (fall history, Berg Balance Scale [BBS], Activities-Specific Balance Confidence [ABC] Scale, Impact of Events Scale, Consequences of Falling Questionnaire [CoFQ]); physical performance (30 Second Sit-to-Stand Test, Timed Up and Go Test, physical activity monitoring); and psychological factors (Zung Anxiety Scale, Beck Depression Inventory [BDI]).

RESULTS

There were no differences between avoiders and nonavoiders for demographic characteristics and fall history (Ps > 0.272). Avoiders had worse MDS-UPDRS (Ps < 0.014) and PDQ-39 scores (Ps < 0.028). Avoiders had poorer balance performance (BBS, P = 0.003), lower balance confidence (ABC, P < 0.001), and more fall catastrophization (CoFQ, P < 0.001). Avoiders reported more depression (P = 0.015) and anxiety (P = 0.028).

DISCUSSION AND CONCLUSIONS

PD FOF avoiders had more involved symptoms and scored lower on balance and physical performance measures. In addition, they reported greater psychological stress. Several potentially mitigable characteristics of those with FOF avoidance behavior were identified.Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A153).

What Adherence Measures Should Be Used in Trials of Home-Based Rehabilitation Interventions? A Systematic Review of the Validity, Reliability, and Acceptability of Measures

OBJECTIVE

To systematically review methods for measuring adherence used in home-based rehabilitation trials and to evaluate their validity, reliability, and acceptability.

DATA SOURCES

In phase 1 we searched the CENTRAL database, NHS Economic Evaluation Database, and Health Technology Assessment Database (January 2000 to April 2013) to identify adherence measures used in randomized controlled trials of allied health professional home-based rehabilitation interventions. In phase 2 we searched the databases of MEDLINE, Embase, CINAHL, Allied and Complementary Medicine Database, PsycINFO, CENTRAL, ProQuest Nursing and Allied Health, and Web of Science (inception to April 2015) for measurement property assessments for each measure.

STUDY SELECTION

Studies assessing the validity, reliability, or acceptability of adherence measures.

DATA EXTRACTION

Two reviewers independently extracted data on participant and measure characteristics, measurement properties evaluated, evaluation methods, and outcome statistics and assessed study quality using the COnsensus-based Standards for the selection of health Measurement INstruments checklist.

DATA SYNTHESIS

In phase 1 we included 8 adherence measures (56 trials). In phase 2, from the 222 measurement property assessments identified in 109 studies, 22 high-quality measurement property assessments were narratively synthesized. Low-quality studies were used as supporting data. StepWatch Activity Monitor validly and acceptably measured short-term step count adherence. The Problematic Experiences of Therapy Scale validly and reliably assessed adherence to vestibular rehabilitation exercises. Adherence diaries had moderately high validity and acceptability across limited populations. The Borg 6 to 20 scale, Bassett and Prapavessis scale, and Yamax CW series had insufficient validity. Low-quality evidence supported use of the Joint Protection Behaviour Assessment. Polar A1 series heart monitors were considered acceptable by 1 study.

CONCLUSIONS

Current rehabilitation adherence measures are limited. Some possess promising validity and acceptability for certain parameters of adherence, situations, and populations and should be used in these situations. Rigorous evaluation of adherence measures in a broader range of populations is needed.

A Method for Quantifying Upper Limb Performance in Daily Life Using Accelerometers

A key reason for referral to rehabilitation services after stroke and other neurological conditions is to improve one's ability to function in daily life. It has become important to measure a person's activities in daily life, and not just measure their capacity for activity in the structured environment of a clinic or laboratory. A wearable sensor that is now enabling measurement of daily movement is the accelerometer. Accelerometers are commercially-available devices resembling large wrist watches that can be worn throughout the day. Data from accelerometers can quantify how the limbs are engaged to perform activities in peoples' homes and communities. This report describes a methodology to collect accelerometry data and turn it into clinically-relevant information. First, data are collected by having the participant wear two accelerometers (one on each wrist) for 24 h or longer. The accelerometry data are then downloaded and processed to produce four different variables that describe key aspects of upper limb activity in daily life: hours of use, use ratio, magnitude ratio, and the bilateral magnitude. Density plots can be constructed that visually represent the data from the 24 h wearing period. The variables and their resultant density plots are highly consistent in neurologically-intact, community-dwelling adults. This striking consistency makes them a useful tool for determining if upper limb daily performance is different from normal. This methodology is appropriate for research studies investigating upper limb dysfunction and interventions designed to improve upper limb performance in daily life in people with stroke and other patient populations. Because of its relative simplicity, it may not be long before it is also incorporated in clinical neurorehabilitation practice.

Estimating bradykinesia severity in Parkinson's disease by analysing gait through a waist-worn sensor

Bradykinesia is a cardinal symptom of Parkinson's disease (PD) and describes the slowness of movement revealed in patients. Current PD therapies are based on dopamine replacement, and given that bradykinesia is the symptom that best correlates with the dopaminergic deficiency, the knowledge of its fluctuations may be useful in the diagnosis, treatment and better understanding of the disease progression. This paper evaluates a machine learning method that analyses the signals provided by a triaxial accelerometer placed on the waist of PD patients in order to automatically assess bradykinetic gait unobtrusively. This method employs Support Vector Machines to determine those parts of the signals corresponding to gait. The frequency content of strides is then used to determine bradykinetic walking bouts and to estimate bradykinesia severity based on an epsilon-Support Vector Regression model. The method is validated in 12 PD patients, which leads to two main conclusions. Firstly, the frequency content of the strides allows for the dichotomic detection of bradykinesia with an accuracy higher than 90%. This process requires the use of a patient-dependant threshold that is estimated based on a leave-one-patient-out regression model. Secondly, bradykinesia severity measured through UPDRS scores is approximated by means of a regression model with errors below 10%. Although the method has to be further validated in more patients, results obtained suggest that the presented approach can be successfully used to rate bradykinesia in the daily life of PD patients unobtrusively.

Clinical Assessments in Parkinson's Disease: Scales and Monitoring

Measurement of disease state is essential in both clinical practice and research in order to assess the severity and progression of a patient's disease status, effect of treatment, and alterations in other relevant factors. Parkinson's disease (PD) is a complex disorder expressed through many motor and nonmotor manifestations, which cause disabilities that can vary both gradually over time or come on suddenly. In addition, there is a wide interpatient variability making the appraisal of the many facets of this disease difficult. Two kinds of measure are used for the evaluation of PD. The first is subjective, inferential, based on rater-based interview and examination or patient self-assessment, and consist of rating scales and questionnaires. These evaluations provide estimations of conceptual, nonobservable factors (e.g., symptoms), usually scored on an ordinal scale. The second type of measure is objective, factual, based on technology-based devices capturing physical characteristics of the pathological phenomena (e.g., sensors to measure the frequency and amplitude of tremor). These instrumental evaluations furnish appraisals with real numbers on an interval scale for which a unit exists. In both categories of measures, a broad variety of tools exist. This chapter aims to present an up-to-date summary of the most relevant characteristics of the most widely used scales, questionnaires, and technological resources currently applied to the assessment of PD. The review concludes that, in our opinion: (1) no assessment methods can substitute the clinical judgment and (2) subjective and objective measures in PD complement each other, each method having strengths and weaknesses.

Monitoring training activity during gait-related balance exercise in individuals with Parkinson's disease: a proof-of-concept-study

BACKGROUND

Despite the benefits of balance exercise in clinical populations, balance training programs tend to be poorly described, which in turn makes it difficult to evaluate important training components and compare between programs. However, the use of wearable sensors may have the potential to monitor certain elements of balance training. Therefore, this study aimed to investigate the feasibility of using wearable sensors to provide objective indicators of the levels and progression of training activity during gait-related balance exercise in individuals with Parkinson's disease.

METHODS

Ten individuals with Parkinson's disease participated in 10 weeks of group training (three sessions/week) addressing highly-challenging balance exercises. The training program was designed to be progressive by gradually increasing the amount of gait-related balance exercise exercises (e.g. walking) and time spent dual-tasking throughout the intervention period. Accelerometers (Actigraph GT3X+) were used to measure volume (number of steps/session) and intensity (time spent walking >1.0 m/s) of dynamic training activity. Training activity was also expressed in relation to the participants' total daily volume of physical activity prior to the training period (i.e. number of steps during training/the number of steps per day). Feasibility encompassed the adequacy of data sampling, the output of accelerometer data and the participants' perception of the level of difficulty of training.

RESULTS

Training activity data were successfully obtained in 98% of the training sessions (n = 256) and data sampling did not interfere with training. Reflecting the progressive features of this intervention, training activity increased throughout the program, and corresponded to a high level of the participants' daily activity (28-43%). In line with the accelerometer data, a majority of the participants (n = 8) perceived the training as challenging.

CONCLUSIONS

The findings of this proof-of-concept study support the feasibility of applying wearable sensors in clinical settings to gain objective informative measures of gait-related balance exercise in individuals with Parkinson's disease. Still, this activity monitoring approach needs to be further validated in other populations and programs including gait-related balance exercises.

TRIAL REGISTRATION

NCT01417598 , 15th August 2011.

Regular Exercise, Quality of Life, and Mobility in Parkinson's Disease: A Longitudinal Analysis of National Parkinson Foundation Quality Improvement Initiative Data

BACKGROUND

Research-based exercise interventions improve health-related quality of life (HRQL) and mobility in people with Parkinson's disease (PD).

OBJECTIVE

To examine whether exercise habits were associated with changes in HRQL and mobility over two years.

METHODS

We identified a cohort of National Parkinson Foundation Quality Improvement Initiative (NPF-QII) participants with three visits. HRQL and mobility were measured with the Parkinson's Disease Questionnaire (PDQ-39) and Timed Up and Go (TUG). We compared self-reported regular exercisers (≥2.5 hours/week) with people who did not exercise 2.5 hours/week. Then we quantified changes in HRQL and mobility associated with 30-minute increases in exercise, across PD severity, using mixed effects regression models.

RESULTS

Participants with three observational study visits (n = 3408) were younger, with milder PD, than participants with fewer visits. After 2 years, consistent exercisers and people who started to exercise regularly after their baseline visit had smaller declines in HRQL and mobility than non-exercisers (p < 0.05). Non-exercisers worsened by 1.37 points on the PDQ-39 and a 0.47 seconds on the TUG per year. Increasing exercise by 30 minutes/week was associated with slower declines in HRQL (-0.16 points) and mobility (-0.04 sec). The benefit of exercise on HRQL was greater in advanced PD (-0.41 points) than mild PD (-0.14 points; p < 0.02).

CONCLUSIONS

Consistently exercising and starting regular exercise after baseline were associated with small but significant positive effects on HRQL and mobility changes over two years. The greater association of exercise with HRQL in advanced PD supports improving encouragement and facilitation of exercise in advanced PD.

Measuring Habitual Physical Activity in Neuromuscular Disorders: A Systematic Review

BACKGROUND

Free-living or habitual physical activity (HPA) refers to someone's performance in his or her free-living environment. Neuromuscular disorders (NMD) manifest through HPA, and the observation of HPA can be used to identify clinical risks and to quantify outcomes in research. This review summarizes and analyses previous studies reporting the assessment of HPA in NMD, and may serve as the basis for evidence-based decision-making when considering assessing HPA in this population.

METHODS

A systematic review was performed to identify all studies related to HPA in NMD, followed by a critical appraisal of the assessment methodology and a final review of the identified HPA tools.

RESULTS

A total of 22 studies were selected, reporting on eight different direct tools (or activity monitors) and ten structured patient-reported outcomes. Overall, HPA patterns in NMD differ from healthy control populations. There was a noticeable lack of validation studies for these tools and outcome measures in NMD. Very little information regarding feasibility and barriers for the application of these tools in this population have been published.

CONCLUSIONS

The variety and heterogeneity of tools and methods in the published literature makes the comparison across different studies difficult, and methodological guidelines are warranted. We propose a checklist of considerations for the assessment and reporting of HPA in NMD.

Assessing Motor Fluctuations in Parkinson's Disease Patients Based on a Single Inertial Sensor

Altered movement control is typically the first noticeable symptom manifested by Parkinson's disease (PD) patients. Once under treatment, the effect of the medication is very patent and patients often recover correct movement control over several hours. Nonetheless, as the disease advances, patients present motor complications. Obtaining precise information on the long-term evolution of these motor complications and their short-term fluctuations is crucial to provide optimal therapy to PD patients and to properly measure the outcome of clinical trials. This paper presents an algorithm based on the accelerometer signals provided by a waist sensor that has been validated in the automatic assessment of patient's motor fluctuations (ON and OFF motor states) during their activities of daily living. A total of 15 patients have participated in the experiments in ambulatory conditions during 1 to 3 days. The state recognised by the algorithm and the motor state annotated by patients in standard diaries are contrasted. Results show that the average specificity and sensitivity are higher than 90%, while their values are higher than 80% of all patients, thereby showing that PD motor status is able to be monitored through a single sensor during daily life of patients in a precise and objective way.

Auditing the Physical Activity and Parkinson Disease Literature Using the Behavioral Epidemiologic Framework

Motor and nonmotor symptoms associated with Parkinson disease place individuals at greater risk of sedentary behaviors and comorbidities. Physical activity is one modifiable means of improving health and reducing the risk of morbidity. We applied a behavioral framework to classify existing research on physical activity and Parkinson disease to describe the current evolution and inform knowledge gaps in this area. Research placed in phase 1 establishes links between physical activity and health-related outcomes; phase 2 develops approaches to quantify physical activity behavior; phase 3 identifies factors associated with implementation of physical activity behaviors; phase 4 assesses the effectiveness of interventions to promote activity; and phase 5 disseminates evidence-based recommendations. Peer-reviewed literature was identified by searching PubMed, Google Scholar, and EBSCO-host. We initially identified 287 potential articles. After further review, we excluded 109 articles, leaving 178 included articles. Of these, 75.84% were categorized into phase 1 (n = 135), 10.11% in phase 2 (n = 18), 9.55% into phase 3 (n = 17), 3.37% into phase 4 (n = 6), and 1.12% into phase 5 (n = 2). By applying the behavioral framework to the physical activity literature for people with Parkinson disease, we suggest this area of research is nascent with more than 75% of the literature in phase 1.

LEVEL OF EVIDENCE

III.

Continuous monitoring of turning in Parkinson's disease: Rehabilitation potential

BACKGROUND

Difficulty turning during gait is a major contributor to mobility disability, falls and reduced quality of life in patients with Parkinson's disease (PD). Unfortunately, the assessment of mobility in the clinic may not adequately reflect typical mobility function or its variability during daily life. We hypothesized that quality of turning mobility, rather than overall quantity of activity, would be impaired in people with PD over seven days of continuous recording.

METHODS

Thirteen subjects with PD and 8 healthy control subjects of similar age wore three Opal inertial sensors (on their belt and on each foot) throughout seven consecutive days during normal daily activities. Turning metrics included average and coefficient of variation (CV) of: (1) number of turns per hour, (2) turn angle amplitude, (3) turn duration, (4) turn mean velocity, and (5) number of steps per turn. Turning characteristics during continuous monitoring were compared with turning 90 and 180 degrees in a observed gait task.

RESULTS

No differences were found between PD and control groups for observed turns. In contrast, subjects with PD showed impaired quality of turning compared to healthy control subjects (Turn Mean Velocity: 43.3 ± 4.8°/s versus 38 ± 5.7°/s, mean number of steps 1.7 ± 1.1 versus 3.2 ± 0.8). In addition, PD patients showed higher variability within the day and across days compared to controls. However, no differences were seen between PD and control subjects in the overall activity (number of steps per day or percent of the day walking) during the seven days.

CONCLUSIONS

We show that continuous monitoring of natural turning during daily activities inside or outside the home is feasible for patients with PD and the elderly. This is the first study showing that continuous monitoring of turning was more sensitive to PD than observed turns. In addition, the quality of turning characteristics was more sensitive to PD than quantity of turns. Characterizing functional turning during daily activities will address a critical barrier to rehabilitation practice and clinical trials: objective measures of mobility characteristics in real-life environments.

Technology in Parkinson's disease: Challenges and opportunities

The miniaturization, sophistication, proliferation, and accessibility of technologies are enabling the capture of more and previously inaccessible phenomena in Parkinson's disease (PD). However, more information has not translated into a greater understanding of disease complexity to satisfy diagnostic and therapeutic needs. Challenges include noncompatible technology platforms, the need for wide-scale and long-term deployment of sensor technology (among vulnerable elderly patients in particular), and the gap between the "big data" acquired with sensitive measurement technologies and their limited clinical application. Major opportunities could be realized if new technologies are developed as part of open-source and/or open-hardware platforms that enable multichannel data capture sensitive to the broad range of motor and nonmotor problems that characterize PD and are adaptable into self-adjusting, individualized treatment delivery systems. The International Parkinson and Movement Disorders Society Task Force on Technology is entrusted to convene engineers, clinicians, researchers, and patients to promote the development of integrated measurement and closed-loop therapeutic systems with high patient adherence that also serve to (1) encourage the adoption of clinico-pathophysiologic phenotyping and early detection of critical disease milestones, (2) enhance the tailoring of symptomatic therapy, (3) improve subgroup targeting of patients for future testing of disease-modifying treatments, and (4) identify objective biomarkers to improve the longitudinal tracking of impairments in clinical care and research. This article summarizes the work carried out by the task force toward identifying challenges and opportunities in the development of technologies with potential for improving the clinical management and the quality of life of individuals with PD. © 2016 International Parkinson and Movement Disorder Society.

Remote Physical Activity Monitoring in Neurological Disease: A Systematic Review

OBJECTIVE

To perform a systematic review of studies using remote physical activity monitoring in neurological diseases, highlighting advances and determining gaps.

METHODS

Studies were systematically identified in PubMed/MEDLINE, CINAHL and SCOPUS from January 2004 to December 2014 that monitored physical activity for ≥24 hours in adults with neurological diseases. Studies that measured only involuntary motor activity (tremor, seizures), energy expenditure or sleep were excluded. Feasibility, findings, and protocols were examined.

RESULTS

137 studies met inclusion criteria in multiple sclerosis (MS) (61 studies); stroke (41); Parkinson's Disease (PD) (20); dementia (11); traumatic brain injury (2) and ataxia (1). Physical activity levels measured by remote monitoring are consistently low in people with MS, stroke and dementia, and patterns of physical activity are altered in PD. In MS, decreased ambulatory activity assessed via remote monitoring is associated with greater disability and lower quality of life. In stroke, remote measures of upper limb function and ambulation are associated with functional recovery following rehabilitation and goal-directed interventions. In PD, remote monitoring may help to predict falls. In dementia, remote physical activity measures correlate with disease severity and can detect wandering.

CONCLUSIONS

These studies show that remote physical activity monitoring is feasible in neurological diseases, including in people with moderate to severe neurological disability. Remote monitoring can be a psychometrically sound and responsive way to assess physical activity in neurological disease. Further research is needed to ensure these tools provide meaningful information in the context of specific neurological disorders and patterns of neurological disability.

A systematic review of the characteristics and validity of monitoring technologies to assess Parkinson's disease

Background

There is growing interest in having objective assessment of health-related outcomes using technology-based devices that provide unbiased measurements which can be used in clinical practice and scientific research. Many studies have investigated the clinical manifestations of Parkinson’s disease using such devices. However, clinimetric properties and clinical validation vary among the different devices.

Methods

Given such heterogeneity, we sought to perform a systematic review in order to (i) list, (ii) compare and (iii) classify technological-based devices used to measure motor function in individuals with Parkinson's disease into three groups, namely wearable, non-wearable and hybrid devices. A systematic literature search of the PubMed database resulted in the inclusion of 168 studies. These studies were grouped based on the type of device used. For each device we reviewed availability, use, reliability, validity, and sensitivity to change. The devices were then classified as (i) ‘recommended’, (ii) ‘suggested’ or (iii) ‘listed’ based on the following criteria: (1) used in the assessment of Parkinson’s disease (yes/no), (2) used in published studies by people other than the developers (yes/no), and (3) successful clinimetric testing (yes/no).

Results

Seventy-three devices were identified, 22 were wearable, 38 were non-wearable, and 13 were hybrid devices. In accordance with our classification method, 9 devices were ‘recommended’, 34 devices were ‘suggested’, and 30 devices were classified as ‘listed’. Within the wearable devices group, the Mobility Lab sensors from Ambulatory Parkinson’s Disease Monitoring (APDM), Physilog®, StepWatch 3, TriTrac RT3 Triaxial accelerometer, McRoberts DynaPort, and Axivity (AX3) were classified as ‘recommended’. Within the non-wearable devices group, the Nintendo Wii Balance Board and GAITRite® gait analysis system were classified as ‘recommended’. Within the hybrid devices group only the Kinesia® system was classified as ‘recommended’.

Electronic supplementary material

The online version of this article (doi:10.1186/s12984-016-0136-7) contains supplementary material, which is available to authorized users.

A Viewpoint on Wearable Technology-Enabled Measurement of Wellbeing and Health-Related Quality of Life in Parkinson's Disease

In this viewpoint, we discuss how several aspects of Parkinson's disease (PD) - known to be correlated with wellbeing and health-related quality of life-could be measured using wearable devices ('wearables'). Moreover, three people with PD (PwP) having exhaustive experience with using such devices write about their personal understanding of wellbeing and health-related quality of life, building a bridge between the true needs defined by PwP and the available methods of data collection. Rapidly evolving new technologies develop wearables that probe function and behaviour in domestic environments of people with chronic conditions such as PD and have the potential to serve their needs. Gathered data can serve to inform patient-driven management changes, enabling greater control by PwP and enhancing likelihood of improvements in wellbeing and health-related quality of life. Data can also be used to quantify wellbeing and health-related quality of life. Additionally these techniques can uncover novel more sensitive and more ecologically valid disease-related endpoints. Active involvement of PwP in data collection and interpretation stands to provide personally and clinically meaningful endpoints and milestones to inform advances in research and relevance of translational efforts in PD.

Ambulatory Activity in People with Early Parkinson's Disease

People with Parkinson's disease (PD) are encouraged to participate in physical activity levels equivalent to those recommended for the general population. Understanding factors that influence this activity is important for facilitating this participation. This study examined factors associated with participation in moderate and high intensity daily ambulatory activity in people with mild to moderate PD. Fifty community-dwelling people with mild-moderate PD were monitored with accelerometers over three days to characterise their daily ambulatory activity levels. Personal factors, disease characteristics, gait and cognitive capacity were measured. Prediction models were created to identify factors influencing ambulation activity. People with PD spent approximately 77 minutes walking per day, mostly at a moderate intensity resulting in a median of 6300 steps/day. Disease severity predicted time spent in moderate ambulation bouts (R2 = 0.116, p = .017). Gait (Timed Up and Go (TUG) Test) and executive function together predicted engagement in high intensity ambulatory activity (R2 > 0.170, p < .022). While disease severity, gait performance and executive function were predictive of engagement in moderate and high intensity walking activity, additional personal and social factors should be considered and are likely to also strongly impact on activity levels.

What Engineering Technology Could Do for Quality of Life in Parkinson's Disease: A Review of Current Needs and Opportunities

Parkinson's disease (PD) involves well-known motor symptoms such as tremor, rigidity, bradykinesia, and altered gait, but there are also nonlocomotory motor symptoms (e.g., changes in handwriting and speech) and even nonmotor symptoms (e.g., disrupted sleep, depression) that can be measured, monitored, and possibly better managed through activity-based monitoring technologies. This will enhance quality of life (QoL) in PD through improved self-monitoring and also provide information that could be shared with a healthcare provider to help better manage treatment. Until recently, nonmotor symptoms ("soft signs") had been generally overlooked in clinical management, yet these are of primary importance to patients and their QoL. Day-to-day variability of the condition, the high variability in symptoms between patients, and the isolated snapshots of a patient in periodic clinic visits make better monitoring essential to the proper management of PD. Continuously monitored patterns of activity, social interactions, and daily activities could provide a rich source of information on status changes, guiding self-correction and clinical management. The same tools can be useful in earlier detection of PD and will improve clinical studies. Remote medical communications in the form of telemedicine, sophisticated tracking of medication use, and assistive technologies that directly compensate for disease-related challenges are examples of other near-term technology solutions to PD problems. Ultimately, a sensor technology is not good if it is not used. The Parkinson's community is a sophisticated early adopter of useful technologies and a group for which engineers can provide near-term gratifying benefits.

Levels and Patterns of Physical Activity and Sedentary Behavior in Elderly People With Mild to Moderate Parkinson Disease

BACKGROUND

Decreased movement ability, one of the hallmarks of Parkinson disease (PD), may lead to inadequate physical activity (PA) and excessive time spent in sedentary behaviors-2 factors associated with an elevated risk for lifestyle-related diseases, poor management of PD, and premature death. To identify the extent to which people with PD are physically active, a comprehensive characterization of PA in this population is needed.

OBJECTIVE

The study objective was to describe levels and patterns of PA and sedentary behaviors in elderly people with PD.

DESIGN

This cross-sectional study involved a free-living setting and 53 men and 42 women (mean age=73.4 years) with mild to moderate idiopathic PD.

METHODS

Time spent in PA and sedentary behaviors was assessed for 1 week with accelerometers.

RESULTS

Mean daily step counts were 4,765; participants spent 589 minutes in sedentary behaviors, 141 minutes in low-intensity activities, 30 minutes in moderate-intensity lifestyle activities, and 16 minutes in moderate- to vigorous-intensity ambulatory activities. No differences were found between weekdays and weekend days. Patterns were characterized by a rise in total PA in the morning, peaking between 10 am and 3 pm, and a gradual decline toward the late evening. The proportion achieving 150 minutes of moderate- to vigorous-intensity PA per week was 27%, and 16% achieved 7,000 or more steps per day.

LIMITATIONS

Nonrandomized selection of participants may limit the generalizability of the results.

CONCLUSIONS

Physical activity levels were generally low, in terms of both total volume and intensity, with only minor variations over the course of a day or between days. These results emphasize the need to develop strategies to increase PA and reduce time spent in sedentary behaviors in elderly people with mild to moderate PD.

Toward Understanding Ambulatory Activity Decline in Parkinson Disease

BACKGROUND

Declining ambulatory activity represents an important facet of disablement in Parkinson disease (PD).

OBJECTIVE

The primary study aim was to compare the 2-year trajectory of ambulatory activity decline with concurrently evolving facets of disability in a small cohort of people with PD. The secondary aim was to identify baseline variables associated with ambulatory activity at 1- and 2-year follow-up assessments.

DESIGN

This was a prospective, longitudinal cohort study.

METHODS

Seventeen people with PD (Hoehn and Yahr stages 1-3) were recruited from 2 outpatient settings. Ambulatory activity data were collected at baseline and at 1- and 2-year annual assessments. Motor, mood, balance, gait, upper extremity function, quality of life, self-efficacy, and levodopa equivalent daily dose data and data on activities of daily living also were collected.

RESULTS

Participants displayed significant 1- and 2-year declines in the amount and intensity of ambulatory activity concurrently with increasing levodopa equivalent daily dose. Worsening motor symptoms and slowing of gait were apparent only after 2 years. Concurrent changes in the remaining clinical variables were not observed. Baseline ambulatory activity and physical performance variables had the strongest relationships with 1- and 2-year mean daily steps.

LIMITATIONS

The sample was small and homogeneous.

CONCLUSIONS

Future research that combines ambulatory activity monitoring with a broader and more balanced array of measures would further illuminate the dynamic interactions among evolving facets of disablement and help determine the extent to which sustained patterns of recommended daily physical activity might slow the rate of disablement in PD.

Defining the clinically meaningful difference in gait speed in persons with Parkinson disease

BACKGROUND AND PURPOSE

Gait dysfunction is a common target for pharmacological, behavioral, and surgical interventions in persons with Parkinson disease. However, the responsiveness of gait speed, that is, clinically important difference, is not well described in the literature for this population. The purpose of this study was to determine the magnitude of meaningful difference in gait speed using multiple methods of assessment and utilizing a large sample of participants inclusive of various stages of disease severity.

METHODS

Gait speed was measured using an instrumented walkway in 324 ambulatory persons with idiopathic Parkinson disease. Cross-sectional analysis of the clinically important difference for gait speed was performed using distribution- and anchor-based approaches: disability (Schwab and England Activities of Daily Living Scale), disease stage (Modified Hoehn and Yahr Scale), and severity (Unified Parkinson's Disease Rating Scale).

RESULTS

Using distribution-based analyses and effect size metrics, the small important difference in gait speed was 0.06 m/s, moderate was 0.14 m/s, and large was 0.22 m/s. Applying previously established cut-points for small, moderate, and large change in the motor scale score, the associated changes in gait speed that might be expected are 0.02, 0.06, and 0.10 m/s.

DISCUSSION AND CONCLUSIONS

Our data revealed that the clinically important difference in gait speed among persons with Parkinson disease on medication ranged from 0.05 m/s to 0.22 m/s by distribution-based analysis and ranged from 0.02 m/s to 0.18 m/s per level within the anchor-based metrics. These data will aid in evaluating the effectiveness of interventions to improve gait speed in persons with Parkinson disease.Video Abstract available. See video (Supplemental Digital Content 1, http://links.lww.com/JNPT/A77) for more insights from the authors.

Role of body-worn movement monitor technology for balance and gait rehabilitation

This perspective article will discuss the potential role of body-worn movement monitors for balance and gait assessment and treatment in rehabilitation. Recent advances in inexpensive, wireless sensor technology and smart devices are resulting in an explosion of miniature, portable sensors that can quickly and accurately quantify body motion. Practical and useful movement monitoring systems are now becoming available. It is critical that therapists understand the potential advantages and limitations of such emerging technology. One important advantage of obtaining objective measures of balance and gait from body-worn sensors is impairment-level metrics characterizing how and why functional performance of balance and gait activities are impaired. Therapy can then be focused on the specific physiological reasons for difficulty in walking or balancing during specific tasks. A second advantage of using technology to measure balance and gait behavior is the increased sensitivity of the balance and gait measures to document mild disability and change with rehabilitation. A third advantage of measuring movement, such as postural sway and gait characteristics, with body-worn sensors is the opportunity for immediate biofeedback provided to patients that can focus attention and enhance performance. In the future, body-worn sensors may allow therapists to perform telerehabilitation to monitor compliance with home exercise programs and the quality of their natural mobility in the community. Therapists need technological systems that are quick to use and provide actionable information and useful reports for their patients and referring physicians. Therapists should look for systems that provide measures that have been validated with respect to gold standard accuracy and to clinically relevant outcomes such as fall risk and severity of disability.

Validation of a portable device for mapping motor and gait disturbances in Parkinson's disease

BACKGROUND

Patients with severe idiopathic Parkinson's disease experience motor fluctuations, which are often difficult to control. Accurate mapping of such motor fluctuations could help improve patients' treatment.

OBJECTIVE

The objective of the study was to focus on developing and validating an automatic detector of motor fluctuations. The device is small, wearable, and detects the motor phase while the patients walk in their daily activities.

METHODS

Algorithms for detection of motor fluctuations were developed on the basis of experimental data from 20 patients who were asked to wear the detector while performing different daily life activities, both in controlled (laboratory) and noncontrolled environments. Patients with motor fluctuations completed the experimental protocol twice: (1) once in the ON, and (2) once in the OFF phase. The validity of the algorithms was tested on 15 different patients who were asked to wear the detector for several hours while performing daily activities in their habitual environments. In order to assess the validity of detector measurements, the results of the algorithms were compared with data collected by trained observers who were accompanying the patients all the time.

RESULTS

The motor fluctuation detector showed a mean sensitivity of 0.96 (median 1; interquartile range, IQR, 0.93-1) and specificity of 0.94 (median 0.96; IQR, 0.90-1).

CONCLUSIONS

ON/OFF motor fluctuations in Parkinson's patients can be detected with a single sensor, which can be worn in everyday life.

The Effects of Highly Challenging Balance Training in Elderly With Parkinson's Disease: A Randomized Controlled Trial

Background. Highly challenging exercises have been suggested to induce neuroplasticity in individuals with Parkinson’s disease (PD); however, its effect on clinical outcomes remains largely unknown. Objective. To evaluate the short-term effects of the HiBalance program, a highly challenging balance-training regimen that incorporates both dual-tasking and PD-specific balance components, compared with usual care in elderly with mild to moderate PD. Methods. Participants with PD (n = 100) were randomized, either to the 10-week HiBalance program (n = 51) or to the control group (n = 49). Participants were evaluated before and after the intervention. The main outcomes were balance performance (Mini-BESTest), gait velocity (during normal and dual-task gait), and concerns about falling (Falls Efficacy Scale–International). Performance of a cognitive task while walking, physical activity level (average steps per day), and activities of daily living were secondary outcomes. Results. A total of 91 participants completed the study. After the intervention, the between group comparison showed significantly improved balance and gait performance in the training group. Moreover, although no significant between group difference was observed regarding gait performance during dual-tasking; the participants in the training group improved their performance of the cognitive task while walking, as compared with the control group. Regarding physical activity levels and activities of daily living, in comparison to the control group, favorable results were found for the training group. No group differences were found for concerns about falling. Conclusions. The HiBalance program significantly benefited balance and gait abilities when compared with usual care and showed promising transfer effects to everyday living. Long-term follow-up assessments will further explore these effects.

Technical and clinical view on ambulatory assessment in Parkinson's disease

With the progress of technologies of recent years, methods have become available that use wearable sensors and ambulatory systems to measure aspects of--particular axial--motor function. As Parkinson's disease (PD) can be considered a model disorder for motor impairment, a significant number of studies have already been performed with these patients using such techniques. In general, motion sensors such as accelerometers and gyroscopes are used, in combination with lightweight electronics that do not interfere with normal human motion. A fundamental advantage in comparison with usual clinical assessment is that these sensors allow a more quantitative, objective, and reliable evaluation of symptoms; they have also significant advantages compared to in-lab technologies (e.g., optoelectronic motion capture) as they allow long-term monitoring under real-life conditions. In addition, based on recent findings particularly from studies using functional imaging, we learned that non-motor symptoms, specifically cognitive aspects, may be at least indirectly assessable. It is hypothesized that ambulatory quantitative assessment strategies will allow users, clinicians, and scientists in the future to gain more quantitative, unobtrusive, and everyday relevant data out of their clinical evaluation and can also be designed as pervasive (everywhere) and intensive (anytime) tools for ambulatory assessment and even rehabilitation of motor and (partly) non-motor symptoms in PD.

Objective biomarkers of balance and gait for Parkinson's disease using body-worn sensors

Balance and gait impairments characterize the progression of Parkinson's disease (PD), predict the risk of falling, and are important contributors to reduced quality of life. Advances in technology of small, body-worn, inertial sensors have made it possible to develop quick, objective measures of balance and gait impairments in the clinic for research trials and clinical practice. Objective balance and gait metrics may eventually provide useful biomarkers for PD. In fact, objective balance and gait measures are already being used as surrogate endpoints for demonstrating clinical efficacy of new treatments, in place of counting falls from diaries, using stop-watch measures of gait speed, or clinical balance rating scales. This review summarizes the types of objective measures available from body-worn sensors. The metrics are organized based on the neural control system for mobility affected by PD: postural stability in stance, postural responses, gait initiation, gait (temporal-spatial lower and upper body coordination and dynamic equilibrium), postural transitions, and freezing of gait. However, the explosion of metrics derived by wearable sensors during prescribed balance and gait tasks, which are abnormal in individuals with PD, do not yet qualify as behavioral biomarkers, because many balance and gait impairments observed in PD are not specific to the disease, nor have they been related to specific pathophysiologic biomarkers. In the future, the most useful balance and gait biomarkers for PD will be those that are sensitive and specific for early PD and are related to the underlying disease process.

Ambulatory activity in incident Parkinson's: more than meets the eye?

Physical activity is important for people with Parkinson's disease (PD) to improve disease-specific impairment and ameliorate secondary consequences related to deconditioning. Activity may also have a neuroprotective role if instigated early. Ambulatory activity has not been examined in incident PD. Eighty-nine newly diagnosed PD cases [mean (SD) age 67.3 (9.9) years] and 97 controls [mean (SD) 69.2 (7.7) years] wore an activity monitor (activPAL™) for 7 days. Volume, pattern and variability outcomes were compared. Accumulation of activity (α) was classified as short (< 30 s), medium (30 s-2 min) and long (> 2 min) bouts of walking. Associations between sustained walking (> 2 min) and motor, cognitive and affective characteristics were identified. Activity outcomes were considered with respect to global health recommendations. Total steps (volume), accumulation of bout length (α), and variability (S2w) outcomes were significantly different (all P < 0.001). PD participants (including Hoehn & Yahr (H&Y) stage I) accumulated significantly less time in long bouts (> 2 min) of walking compared with controls, due to performing fewer long bouts, rather than a reduction in time spent in walking per bout. For PD and controls there were weak but significant correlations for a range of characteristics and sustained walking. Fewer people with PD achieved the recommended 30 min of walking per day comprised of bouts > 10 min (P = 0.02) and bouts > 2 min (P < 0.001). People with PD were significantly less active than controls, with an inability to sustain levels of walking, and with differences apparent very early on in the disease process. A focus on increasing general ambulatory activity and exercise from the outset is recommended.

Feasibility of a virtual exercise coach to promote walking in community-dwelling persons with Parkinson disease

OBJECTIVE

The short-term benefits of exercise for persons with Parkinson disease (PD) are well established, but long-term adherence is limited. The aim of this study was to explore the feasibility, acceptability, and preliminary evidence of the effectiveness of a virtual exercise coach to promote daily walking in community-dwelling persons with Parkinson disease.

DESIGN

Twenty subjects with Parkinson disease participated in this phase 1, single-group, nonrandomized clinical trial. The subjects were instructed to interact with the virtual exercise coach for 5 mins, wear a pedometer, and walk daily for 1 mo. Retention rate, satisfaction, and interaction history were assessed at 1 mo. Six-minute walk and gait speed were assessed at baseline and after the intervention.

RESULTS

Fifty-five percent of the participants were women, and the mean age was 65.6 yrs. At the study completion, there was 100% retention rate. The subjects had a mean satisfaction score of 5.6/7 (with 7 indicating maximal satisfaction) with the virtual exercise coach. Interaction history revealed that the participants logged in for a mean (SD) of 25.4 (7) days of the recommended 30 days. The mean adherence to daily walking was 85%. Both gait speed and the 6-min walk test significantly improved (P < 0.05). No adverse events were reported.

CONCLUSIONS

Sedentary persons with Parkinson disease successfully used a computer and interacted with a virtual exercise coach. Retention, satisfaction, and adherence to daily walking were high for 1 mo, and significant improvements were seen in mobility.