Test-retest reliability of 24 hours of activity monitoring in individuals with Parkinson's disease in home and community

Systematic Review Looking at the Use of Technology to Measure Free-Living Symptom and Activity Outcomes in Parkinson's Disease in the Home or a Home-like Environment

BACKGROUND

The emergence of new technologies measuring outcomes in Parkinson's disease (PD) to complement the existing clinical rating scales has introduced the possibility of measurement occurring in patients' own homes whilst they freely live and carry out normal day-to-day activities.

OBJECTIVE

This systematic review seeks to provide an overview of what technology is being used to test which outcomes in PD from free-living participant activity in the setting of the home environment. Additionally, this review seeks to form an impression of the nature of validation and clinimetric testing carried out on the technological device(s) being used.

METHODS

Five databases (Medline, Embase, PsycInfo, Cochrane and Web of Science) were systematically searched for papers dating from 2000. Study eligibility criteria included: adults with a PD diagnosis; the use of technology; the setting of a home or home-like environment; outcomes measuring any motor and non-motor aspect relevant to PD, as well as activities of daily living; unrestricted/unscripted activities undertaken by participants.

RESULTS

65 studies were selected for data extraction. There were wide varieties of participant sample sizes (<10 up to hundreds) and study durations (<2 weeks up to a year). The metrics evaluated by technology, largely using inertial measurement units in wearable devices, included gait, tremor, physical activity, bradykinesia, dyskinesia and motor fluctuations, posture, falls, typing, sleep and activities of daily living.

CONCLUSIONS

Home-based free-living testing in PD is being conducted by multiple groups with diverse approaches, focussing mainly on motor symptoms and sleep.

People With Aneurysmal Subarachnoid Hemorrhage Have Low Physical Fitness and Can Be Predisposed to Inactive and Sedentary Lifestyles

BACKGROUND

Physical inactivity, sedentary lifestyles, and low functional outcome are thought to impact the level of physical fitness in patients with aneurysmal subarachnoid hemorrhage (a-SAH). However, changes in fitness over time and associated factors have not been studied in a-SAH.

OBJECTIVE

The objective was to evaluate the level of physical fitness in the first year after a-SAH and explore longitudinal relations with physical activity, sedentary behavior, and functional outcome. Additionally, we evaluated whether physical fitness could be predicted by disease-related characteristics (ie, severity of a-SAH, location of the aneurysm, treatment procedure, pituitary dysfunction, and complications).

DESIGN

This was a prospective 1-year follow-up study.

METHODS

Fifty-two participants performed exercise testing at 6 and 12 months after a-SAH. Cardiopulmonary exercise testing and isokinetic dynamometry were applied to determine the peak oxygen uptake $({\rm{\dot{V}}}{{\rm{o}}_{2{\rm{peak}}}})$ and the peak torque of the knee extensors (PText) and flexors (PTflex). In addition, physical activity and sedentary behavior were evaluated by accelerometer-based activity monitoring. The functional outcome was assessed by the Functional Independence Measure and Functional Assessment Measure. Disease-related characteristics were collected at hospital intake.

RESULTS

At both 6 and 12 months, all fitness parameters were lower compared with predicted values (ranging from 18% to 28%). Physical activity is related to both ${\rm{\dot{V}}}{{\rm{o}}_{{\rm{2peak}}}}$ and PTflex. The Functional Independence Measure and Functional Assessment Measure scores was related to PText and PTflex. Further, participants who underwent surgical clipping had lower ${\rm{\dot{V}}}{{\rm{o}}_{{\rm{2peak}}}}$ and PTflex.

LIMITATIONS

Longitudinal observations cannot confirm causality.

CONCLUSIONS

Levels of physical fitness remain low over the first year after a-SAH. Participants who were physically more active had higher levels of physical fitness, whereas participants with impaired functional outcome or who were treated with surgical clipping were at risk of low physical fitness. Exercise interventions are warranted and should focus on the promotion of physical activity and target patients with impaired functional outcome or those who have been treated with surgical clipping.

Physical activity in wheelchair-using youth with spina bifida: an observational study

BACKGROUND

Even though typically developing youth are already at risk for physical inactivity, youth with spina bifida may be even at higher risk as a consequence of their reduced mobility. No objective data is available for youth with spina bifida who use a manual wheelchair, so the seriousness of the problem is unknown. The purpose of this observational study was to quantify physical activity in wheelchair-using youth with spina bifida and evaluate the intensity of activities.

METHODS

Fifty-three children and adolescents (5-19 years) with spina bifida who use a manual wheelchair for daily life, long distances or sports were included. To assess time spent in several types of activities VitaMove data of 34 participants were used and were presented as time spent sedentary and time spent physically active. This was compared to reference data of typically developing youth. To assess time spent in several intensities Actiheart data of 36 participants were used. The intensities were categorized according to the American College of Sports Medicine, ranging from very light intensity to near to maximal intensity. Data of 25 participants were used to combine type of activity and intensity.

RESULTS

Children and adolescents with spina bifida who use a manual wheelchair were more sedentary (94.3% versus 78.0% per 24 h, p < 0.000) and less physically active (5.0% versus 12.2% per 24 h, p < 0.000) compared to typically developing peers. Physical activity during weekend days was worse compared to school days; 19% met the Guidelines of Physical Activity during school days and 8% during weekend days. The intensities per activity varied extensively between participants.

CONCLUSIONS

Children and adolescents with spina bifida who use a manual wheelchair are less physically active and more sedentary than typically developing youth. The physical activity levels on school days seem to be more favorable than the physical activity levels on a weekend day. The low levels of physical activity need our attention in pediatric rehabilitation practice. The different intensities during activities indicate the importance of individually tailored assessments and interventions.

Evaluation of smartphone-based testing to generate exploratory outcome measures in a phase 1 Parkinson's disease clinical trial

BACKGROUND

Ubiquitous digital technologies such as smartphone sensors promise to fundamentally change biomedical research and treatment monitoring in neurological diseases such as PD, creating a new domain of digital biomarkers.

OBJECTIVES

The present study assessed the feasibility, reliability, and validity of smartphone-based digital biomarkers of PD in a clinical trial setting.

METHODS

During a 6-month, phase 1b clinical trial with 44 Parkinson participants, and an independent, 45-day study in 35 age-matched healthy controls, participants completed six daily motor active tests (sustained phonation, rest tremor, postural tremor, finger-tapping, balance, and gait), then carried the smartphone during the day (passive monitoring), enabling assessment of, for example, time spent walking and sit-to-stand transitions by gyroscopic and accelerometer data.

RESULTS

Adherence was acceptable: Patients completed active testing on average 3.5 of 7 times/week. Sensor-based features showed moderate-to-excellent test-retest reliability (average intraclass correlation coefficient = 0.84). All active and passive features significantly differentiated PD from controls with P < 0.005. All active test features except sustained phonation were significantly related to corresponding International Parkinson and Movement Disorder Society-Sponsored UPRDS clinical severity ratings. On passive monitoring, time spent walking had a significant (P = 0.005) relationship with average postural instability and gait disturbance scores. Of note, for all smartphone active and passive features except postural tremor, the monitoring procedure detected abnormalities even in those Parkinson participants scored as having no signs in the corresponding International Parkinson and Movement Disorder Society-Sponsored UPRDS items at the site visit.

CONCLUSIONS

These findings demonstrate the feasibility of smartphone-based digital biomarkers and indicate that smartphone-sensor technologies provide reliable, valid, clinically meaningful, and highly sensitive phenotypic data in Parkinson's disease. © 2018 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

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.

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.

Prospective change in daily walking over 2 years in older adults with or at risk of knee osteoarthritis: the MOST study

OBJECTIVE

Radiographic disease and knee pain are thought to decrease physical activity in people with knee osteoarthritis (OA), but this has not been formally studied. We examined change in objectively measured daily walking over 2 years and evaluated the association of certain risk factors with reduced walking among adults with or at risk of knee OA.

DESIGN

Steps/day over 7 days were collected at baseline and 2 years later in subjects with or at risk of knee OA from the Multicenter Osteoarthritis Study using a StepWatch. We evaluated the presence of radiographic knee osteoarthritis (ROA), knee pain, worsening of ROA and pain over 2 years, obesity, depressive symptoms, living situation, catastrophizing, fatigue, widespread pain and comorbidities with 2-year change in daily walking using regression models adjusted for potential confounders.

RESULTS

1318 met inclusion criteria (age 66.9 ± 7.7, 59% women, BMI 30.6 ± 5.9) and walked 126 ± 1700 steps/day fewer steps at 2 years (95% CI [-218, -35]). People with depressive symptoms at baseline walked 455 fewer steps/day [-872, -68], and there was a trend for people with ROA worsening to walk 183 fewer steps/day [-377.5, 11.7]. No other factors met statistical significance for change in daily walking.

CONCLUSION

Adults with or at risk of knee OA experienced only minimal declines in daily walking over 2 years. Nonetheless, depressive symptoms and may be worsening ROA are associated with a decline in steps/day in adults with or at risk of knee OA.

A behavioural intervention increases physical activity in people with subacute spinal cord injury: a randomised trial

QUESTIONS

For people with subacute spinal cord injury, does rehabilitation that is reinforced with the addition of a behavioural intervention to promote physical activity lead to a more active lifestyle than rehabilitation alone?

DESIGN

Randomised, controlled trial with concealed allocation, intention-to-treat analysis, and blinded assessors.

PARTICIPANTS

Forty-five adults with subacute spinal cord injury who were undergoing inpatient rehabilitation and were dependent on a manual wheelchair. The spinal cord injuries were characterised as: tetraplegia 33%; motor complete 62%; mean time since injury 150 days (SD 74).

INTERVENTION

All participants received regular rehabilitation, including handcycle training. Only the experimental group received a behavioural intervention promoting an active lifestyle after discharge. This intervention involved 13 individual sessions delivered by a coach who was trained in motivational interviewing; it began 2 months before and ended 6 months after discharge from inpatient rehabilitation.

OUTCOME MEASURES

The primary outcome was physical activity, which was objectively measured with an accelerometer-based activity monitor 2 months before discharge, at discharge, and 6 and 12 months after discharge from inpatient rehabilitation. The accelerometry data were analysed as total wheeled physical activity, sedentary time and motility. Self-reported physical activity was a secondary outcome.

RESULTS

The behavioural intervention significantly increased wheeled physical activity (overall between-group difference from generalised estimating equation 21minutes per day, 95% CI 8 to 35). This difference was evident 6 months after discharge (28minutes per day, 95% CI 8 to 48) and maintained at 12 months after discharge (25minutes per day, 95% CI 1 to 50). No significant intervention effect was found for sedentary time or motility. Self-reported physical activity also significantly improved.

CONCLUSION

The behavioural intervention was effective in eliciting a behavioural change toward a more active lifestyle among people with subacute spinal cord injury.

TRIAL REGISTRATION

NTR2424.

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.

An Emerging Era in the Management of Parkinson's Disease: Wearable Technologies and the Internet of Things

Current challenges demand a profound restructuration of the global healthcare system. A more efficient system is required to cope with the growing world population and increased life expectancy, which is associated with a marked prevalence of chronic neurological disorders such as Parkinson's disease (PD). One possible approach to meet this demand is a laterally distributed platform such as the Internet of Things (IoT). Real-time motion metrics in PD could be obtained virtually in any scenario by placing lightweight wearable sensors in the patient's clothes and connecting them to a medical database through mobile devices such as cell phones or tablets. Technologies exist to collect huge amounts of patient data not only during regular medical visits but also at home during activities of daily life. These data could be fed into intelligent algorithms to first discriminate relevant threatening conditions, adjust medications based on online obtained physical deficits, and facilitate strategies to modify disease progression. A major impact of this approach lies in its efficiency, by maximizing resources and drastically improving the patient experience. The patient participates actively in disease management via combined objective device- and self-assessment and by sharing information within both medical and peer groups. Here, we review and discuss the existing wearable technologies and the Internet-of-Things concept applied to PD, with an emphasis on how this technological platform may lead to a shift in paradigm in terms of diagnostics and treatment.

Can a lifestyle intervention programme improve physical behaviour among adolescents and young adults with spastic cerebral palsy? A randomized controlled trial

AIM

Optimal physical behaviour is important, as physical inactivity contributes to functional deterioration and reduced social participation. Nevertheless, research showed that persons with cerebral palsy (CP) have low physical activity levels. The objective of this study is to evaluate the effectiveness of a lifestyle intervention programme on physical behaviour.

METHOD

Fifty-seven persons (36 completed the total study) with spastic CP (age range 16 to 25y; 27 males, 30 females), classified as Gross Motor Function Classification System levels I-IV were included in this randomized controlled trial. Twenty-nine participants had a unilateral CP and 27 had a bilateral CP. A 6-month lifestyle intervention consisting of fitness training and counselling on physical behaviour and sports participation was evaluated. Physical behaviour was objectively measured using ambulatory activity monitors. Self-reported physical activity was determined using the Physical Activity Scale for Individuals with Physical Disabilities.

RESULTS

The intervention did not affect the objectively measured physical activity during the intervention (beta=0.34, CI=-1.70 to 2.37) or at follow-up (beta=0.30, CI=-1.99 to 2.59). Self-reported physical activity was positively affected during the intervention period (beta=7.61, CI=0.17-15.05); however, this effect was not present at follow-up (beta=3.65, CI=-3.05 to 10.36).

INTERPRETATION

The lifestyle intervention was ineffective in eliciting a behavioural change towards more favourable physical behaviour in adolescents and young adults with spastic CP.

Inactive and sedentary lifestyles amongst ambulatory adolescents and young adults with cerebral palsy

Background

To assess physical behaviour, including physical activity and sedentary behaviour, of ambulatory adolescents and young adults with cerebral palsy (CP). We compared participant physical behaviour to that of able-bodied persons and assessed differences related to Gross Motor Functioning Classification System (GMFCS) level and CP distribution (unilateral/bilateral).

Methods

In 48 ambulatory persons aged 16 to 24 years with spastic CP and in 32 able-bodied controls, physical behaviour was objectively determined with an accelerometer-based activity monitor. Total duration, intensity and type of physical activity were assessed and sedentary time was determined (lying and sitting). Furthermore, distribution of walking bouts and sitting bouts was specified.

Results

Adolescents and young adults with CP spent 8.6% of 24 hours physically active and 79.5% sedentary, corresponding with respectively 123 minutes and 1147 minutes per 24 hours. Compared to able-bodied controls, persons with CP participated 48 minutes less in physical activities (p < 0.01) and spent 80 minutes more sedentary per 24 hours (p < 0.01). Physical behaviour was not different between persons with GMFCS level I and II and only number of short sitting bouts were significantly more prevalent in persons with bilateral CP compared to unilateral CP (p < 0.05).

Conclusions

Ambulatory adolescents and young adults with CP are less physically active and spend more time sedentary compared to able-bodied persons, suggesting that this group may be at increased risk for health problems related to less favourable physical behaviour.

Trial registration

Nederlands trial register: NTR1785

Home-based system for physical activity monitoring in patients with multiple sclerosis (Pilot study)

Background

Limitations in physical activity are considered as a key problem in patients with multiple sclerosis (PwMS). Contemporary methods to assess the level of physical activity in PwMS are regular clinical observation. However, these methods either rely on high recall and accurate reporting from the patients (e.g. self-report questionnaires), or they are conducted during a particular clinical assessment with predefined activities. Therefore, the main aim of this pilot study was to develop an objective method to gather information about the real type and intensity of daily activities performed by PwMS in every-day living situations using an accelerometer. Furthermore, the accelerometer-derived measures are investigated regarding their potential for discriminating between different MS groups.

Methods

Eleven PwMS that were able to walk independently (EDSS ≤ 5) were divided into two groups: mild disability (EDSS 1–2.5; n = 6) and moderate disability (EDSS 3 –5; n = 5). Participants made use of an activity monitor device attached to their waist during their normal daily activities over 4 measurements. Activity parameters were assessed and compared for the time of each participant’s first measurement and follow-up measurement. Furthermore, differences between both subgroups, and the correlation of activity parameters with the clinical neurological variable (EDSS) were investigated.

Results

Participants showed significant decline in step count (p = 0.008), maximum walking speed (p = 0.02) and physical activity intensity (p = 0.03) throughout the study period. Compared to the mild subgroup, moderate affected participant accumulated less number of steps (G1: 9214.33 ± 2439.11, G2: 5018.13 ± 2416.96; p < 0.005) and were slower (G1: 1.48 ± 0.19, G2: 1.12 ± 0.44; p = 0.03). Additionally, the EDSS correlated negatively with mean walking speed (r = - 0.71, p = 0.01) and steps count (r = - 0.54, p = 0.08).

Conclusions

In this study, we used a portable activity monitoring sensor to gather information about everyday physical activity in PwMS at home. We showed that objective measurements using simple 3D accelerometers can track daily physical activity fluctuation. Furthermore, they track disability changes better than clinical measures. Thus, they can help to develop activity based treatments for PwMS.

Physical strain of walking relates to activity level in adults with cerebral palsy

OBJECTIVE

To gain insight into underlying mechanisms of inactive lifestyles among adults with spastic bilateral cerebral palsy (CP) with a focus on aerobic capacity, oxygen consumption, and physical strain during walking at preferred walking speed, as well as fatigue.

DESIGN

Cross-sectional.

SETTING

University hospital.

PARTICIPANTS

Adults (N=36), aged 25 to 45 years, with spastic bilateral CP, walking with (n=6) or without (n=30) walking aids.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Physical strain during walking was defined as oxygen uptake during walking, expressed as percentage of peak aerobic capacity. Participants with spastic bilateral CP walked their preferred walking speed while oxygen uptake was measured using a portable gas analyzer. Peak aerobic capacity was measured during maximal cycle ergometry. An accelerometry-based activity monitor measured total daily walking time. Regression analyses were performed to assess the relation between aerobic capacity, oxygen uptake, and physical strain of walking on the one hand and total daily walking time on the other hand.

RESULTS

Neither aerobic capacity nor oxygen uptake during walking was related to total daily walking time (r(2)=.29, P=.10 and r(2)=.27, P=.16, respectively). Physical strain of walking at preferred walking speed was inversely related to total daily walking time (r(2)=.44, P<.01).

CONCLUSIONS

Physical strain during walking is moderately related to total daily walking time, implying that people with high physical strain during walking at preferred walking speed likely walk less in daily life.

Capturing ambulatory activity decline in Parkinson's disease

BACKGROUND AND PURPOSE

Relatively little is known about the natural evolution of physical activity-related participation restrictions associated with Parkinson's disease (PD). We examined this issue prospectively, using continuous monitoring technology to capture the free-living ambulatory activity of persons with PD engaging in life situations. We specifically sought (1) to explore natural, long-term changes in daily ambulatory activity and (2) to compare the responsiveness of ambulatory activity parameters to clinical measures of gait and disease severity.

METHODS

Thirty-three persons with PD participated (Hoehn and Yahr range of 1-3). Participants wore a step activity monitor for up to 7 days at baseline and again at 1-year follow-up. Mean daily values were calculated for parameters indicative of amount, intensity, frequency, and duration of ambulatory activity. Clinical measures included the Unified Parkinson Disease Rating Scale, the 6-Minute Walk, and Maximal Gait Speed. Parametric tests for paired samples were used to investigate changes in ambulatory activity parameters and clinical measures.

RESULTS

Participants had significant declines in the amount and intensity of daily ambulatory activity but not in its frequency and duration (P < 0.007). Declines occurred in the absence of changes in clinical measures of gait or disease severity. The greatest 1-year decline occurred in the number of daily minutes participants spent engaging in at least moderate-intensity ambulatory activity.

CONCLUSION

Continuous monitoring of ambulatory activity beyond mere step counts may serve as a distinct and important means of quantifying declining ambulatory behavior associated with disease progression or improved ambulatory behavior resulting from rehabilitation and medical and/or surgical interventions in persons with PD.

Continuous monitoring of functional activities using wearable, wireless gyroscope and accelerometer technology

The development of functional activity monitors (FAMs) will allow rehabilitation researchers and clinicians to evaluate treatment efficacy, to monitor compliance to exercise instructions, and to provide real time feedback in the treatment of movement disorders during the performance of daily activities. The purpose of the present study was to develop and test a small sized wearable FAM system comprised of three sensors positioned on the sternum and both thighs, wireless Bluetooth transmission capability to a smartphone, and computationally efficient activity detection algorithms for the accurate detection of functional activities. Each sensor was composed of a tri-axial accelerometer and a tri-axial gyroscope. Computationally efficient activity recognition algorithms were developed, using a sliding window of 1 second, the variability of the tilt angle time series and power spectral analysis. In addition, it includes a decision tree that identifies postures such as sitting, standing and lying, walking at comfortable, slow and fast speeds, transitions between these functional activities (e.g, sit-to-stand and stand-to-sit), activity duration and step frequency. In a research lab setting the output of the FAM system, video recordings and a 3D motion analysis system were compared in 10 healthy young adults. The results show that the agreement between the FAM system and the video recordings ranged from 98.10% to 100% for all postures, transfers and walking periods. There were no significant differences in activity durations and step frequency between measurement instruments.

Toward Automated, At-Home Assessment of Mobility Among Patients With Parkinson Disease, Using a Body-Worn Accelerometer

Objective. To develop an automated and objective method to assess mobility in Parkinson disease (PD) patients in daily-life settings and to investigate whether accelerometer-derived measures discriminate between PD and healthy controls as they walk and simulate activities of daily living (ADL). Methods. Healthy older adults (17) and patients with PD (22) wore a triaxial accelerometer on their lower back during short walks (validation study) and during a walk around the medical center to simulate daily activities (ADL simulation). The variability (consistency and rhythmicity) of stepping was assessed. The patients completed the walks before and after taking their anti-Parkinsonian medications. Frequency-based acceleration measures included dominant frequency, amplitude (strength of signal frequency), width (frequency dispersion), and slope (a combination reflecting amplitude and width) of the main frequency of the power spectral density in the 0.5- to 3.0-Hz band. A subset of the Unified Parkinson-Disease Rating Scale provided a clinical measure of gait impairment (UPDRS-Gait5). A PD patient and control wore the sensors for 3 days at home. Results. The width was larger, and the amplitude and slope were smaller in the PD patients compared to the controls in the validation study and ADL simulation ( P < .02). The width decreased, and the amplitude and slope increased when patients took anti-Parkinsonian medications ( P < .007). Significant correlations were observed between acceleration-derived measures and UPDRS-Gait5. The data obtained at home was similar to the clinic data. Conclusions. Frequency-derived measures are valid and sensitive estimates of stride-to-stride variability that can be used to assess the quality and consistency of walking in patients with PD in real-life settings.

Accelerometry-based activity spectrum in persons with chronic physical conditions

OBJECTIVES

(1) To give an overview of the impact of a variety of chronic physical conditions on accelerometry-based levels of everyday physical activity and to identify high-risk conditions; and (2) to compare these objectively assessed activity levels with the levels estimated by rehabilitation physicians.

INTERVENTIONS

Not applicable.

DESIGN

Cross-sectional study.

SETTING

Participant's home environment.

PARTICIPANTS

Patients (n=461) with 18 chronic physical (sub)conditions and able-bodied subjects (n=96).

MAIN OUTCOME MEASURES

We summarized data on the level of everyday physical activity as objectively measured with an accelerometry-based activity monitor. Thirty-one rehabilitation physicians filled in a questionnaire designed to obtain their estimates of the level of physical activity in patients with the various conditions.

RESULTS

Only 4 of the studied conditions had normal activity levels (≥90% of the able-bodied level). Persons with transtibial amputation (vascular), spinal cord injury, and myelomeningocele (wheelchair dependent) had the lowest levels of activity, less than 40% of the able-bodied level. In general, rehabilitation physicians were aware of the inactive lifestyles, but considerably underestimated the magnitude of inactivity in the high-risk conditions.

CONCLUSIONS

This is the first study to provide an objectively assessed activity spectrum in a variety of chronic physical conditions. We hope this study will increase the awareness of health professionals as to which chronic physical conditions are at increased risk for an inactive lifestyle, and will contribute to adaptation of patient management accordingly.

Charting the progression of disability in Parkinson disease: study protocol for a prospective longitudinal cohort study

BACKGROUND

People with Parkinson disease (PD), even in the presence of symptomatic relief from medical, surgical, and rehabilitative interventions, face a persistent worsening of disability. This disability is characterized by diminished quality of life, reduced functional mobility, declining performance in activities of daily living and worsening neurological impairments. While evidence has emerged supporting the clinically meaningful benefits of short-term exercise programs on these underlying factors, assertions regarding the effects of sustained programs of exercise and physical activity on the trajectory of disablement in PD are made in the absence of direct evidence. Indeed, the natural decline in quality of life and functional mobility in people diagnosed with PD is poorly understood. Moreover, outcome measures commonly used in clinical exercise trials typically do not capture the full spectrum of disability as defined by the World Health Organization (WHO).

METHODS/DESIGN

The objective of this multicenter prospective study will be to examine the 2-year trajectory of disablement in a cohort of persons with PD. Two hundred sixty participants will be recruited to produce an expected final sample size of 150 individuals. Participants will be included if they are greater than 40 years of age, have a neurologist confirmed diagnosis of idiopathic PD, and are at Hoehn and Yahr stages 1 through 4. Data will be collected every 6 months during the study period. Primary outcome measures reflecting a broad spectrum of disablement will include, but will not be limited to, MDS-UPDRS, Timed Up and Go, Berg Balance Test, Nine Hole Peg Test, PDQ-39, and directly monitored ambulatory activity. Self-reported exercise and physical activity data also will be recorded. Statistical analyses will be used to characterize the trajectory of disablement and examine the influence of its underlying contributing factors.

DISCUSSION

Tertiary prevention is an important component of contemporary healthcare for individuals living with degenerative disease. For individuals with PD, there is growing recognition that exercise and/or physical activity efforts to slow the rate of functional mobility decline, in particular, may be critical for optimizing quality of life. By describing the natural trajectory of disablement, exercise habits, and physical activity in a cohort of persons with PD, this investigation will establish an important foundation for future intervention research. Specifically, through the evaluation of the influence of sustained exercise and physical activity on disablement, the study will serve as a preliminary step toward developing a randomized controlled trial of long-term exercise in persons with PD.

Assessing mobility at home in people with early Parkinson's disease using an instrumented Timed Up and Go test

Gait and mobility problems are prominent features of Parkinson's Disease (PD), and are difficult to observe clinically in early stages of PD. We previously reported that gait changes were measurable in early to mid-stage PD subjects, when we used inertial sensors during an instrumented Timed Up and Go test (iTUG). With the advent of wearable inertial sensors, home assessment of mobility has become possible. We tested six people with early PD and eight control subjects using the iTUG in the home and laboratory. Our objectives were to 1) investigate the feasibility of testing subjects at home, and 2) compare performance at home versus laboratory. We found that home iTUG testing is feasible and the patients with PD were more affected than the healthy control subjects when tested at home.

Does Cueing Training Improve Physical Activity in Patients With Parkinson’s Disease?

Background. Patients with Parkinson’s disease (PD) are encouraged to stay active to maintain their mobility. Ambulatory activity monitoring (AM) provides an objective way to determine type and amount of gait-related daily activities. Objective . To investigate the effects of a home cueing training program on functional walking activity in PD. Methods. In a single-blind, randomized crossover trial, PD patients allocated to early intervention received cueing training for 3 weeks, whereas the late intervention group received training in the following 3 weeks. Training was applied at home, using a prototype cueing device. AM was applied at baseline, 3, 6, and 12 weeks in the patient’s home, to record body movements. Postures and motions were classified as percentage of total time spent on ( a) static activity, further specified as % sitting and % standing, and ( b) % dynamic activity, further specified as % walking, % walking periods exceeding 5 seconds (W>" xbd="1983" xhg="1960" ybd="1440" yhg="1401"/>5s) and 10 seconds (W>10s). Random coefficient analysis was applied. Results. A total of 153 patients participated in this trial. Significant improvements were found for dynamic activity (β= 4.46; P < .01), static activity (β=-3.34; P < .01), walking (β= 4.23; P < .01), W>5s (β = 2.63; P < .05), and W>10s (β = 2.90; P < .01). All intervention effects declined significantly at 6 weeks follow-up. Conclusion. Cueing training in PD patients’ own home significantly improves the amount of walking as recorded by AM. Treatment effects reduced after the intervention period, pointing to the need for permanent cueing devices and follow-up cueing training.

Identifying fallers with Parkinson's disease using home-based tests: who is at risk?

The objective of this work is to determine risk factors for falling in patients with Parkinson's disease (PD) using home-based assessments and develop a prediction model. Data on falls, balance, gait-related activities, and nonmotor symptoms were obtained from 153 PD patients (Hoehn-Yahr 2-4) in their home. Fifty-one candidate determinants for falling were independently tested using bivariate logistic regression analysis. A multivariate logistic regression model was developed to identify patients susceptible to falls. Sixty-six subjects (43%) were classified as fallers. Eighteen determinants for falling were selected. The final multivariate model showed an accuracy of 74% and included: (1) Freezing of Gait Questionnaire, (2) Timed Get Up and Go (TGUG) score, (3) disease duration, (4) item 15 of the Unified Parkinson's Disease Rating Scale. Based on disease duration, freezing symptoms, walking problems, and a prolonged TGUG duration, assessed in the home situation, it was possible to accurately identify 74% of PD patients as fallers.