Parkinson disease (PD) is a movement disorder affecting more than 1 million people in the United States and an estimated 4 million to 6 million worldwide. One of the chief complaints of persons with PD is deteriorating movement and mobility, resulting in slowness of walking and an increased risk of falls. A variety of forms of exercise have shown promise at improving gait and balance.1,2 Exercise has led to gains in functional ability,3 balance,4 as well as gait and quality of life.5 A recent National Parkinson Foundation study6 reported that regular exercise (>150 min/wk) was associated with a slower decline in mobility and quality of life and was also associated with less cognitive decline, slower progression of disease, and less caregiver burden 1 year later.
These gains have the potential to be maintained with continued exercise programs.7 Ongoing vigorous exercise, defined as resulting in an increased heart rate and an increased need for oxygen, may also have a neuroprotective effect in people with PD.8 In addition, the potential for neuroplasticity, such as reversal of dendritic spine loss demonstrated in animal models9 and exercise-induced increases in human dopamine binding,10 provides further evidence that continued exercise is important.
Physical therapy for PD often includes a regular exercise component. However, physical therapists (PTs) are concerned that initial improvement in mobility may not be maintained if the patients do not adhere to the prescribed home exercise program (HEP) after discharge from physical therapy services. Adherence to an HEP following physical therapy interventions has been examined across a variety of patient populations with a wide range of findings. Long-term adherence rates have been reported as low as 30% to 35% among the general population.11 Some studies report higher adherence. A study of older adults with impaired balance12 found that 53% continued exercise at home. Two studies of patients with PD performing home exercises13,14 reported higher adherence, ranging from 72% to 86%. Thus, it is difficult to obtain a clear understanding of adherence rates across studies because of the wide variety of conditions and methods; reliability is questionable, as most home exercise rates are self-reported.15 Despite the lack of a uniform outcome measure, a broad variety of factors have been identified as negatively affecting adherence, including perceived barriers to exercise, misunderstanding of the exercise regimen, lack of positive feedback, low self-efficacy, and loss of personal contact with the PT.11,16‐18
This case report describes an initial field test of a new telehealth system—System for Technology-Augmented Rehabilitation and Training (START)—to augment the delivery of the Lee Silverman Voice Technique BIG (LSVT BIG) therapy protocol to a person with PD. One of the primary goals for START is to help improve adherence to an HEP; it was designed to positively impact many of the factors affecting adherence to exercise as discussed previously. START is an automated assistant designed to guide and provide feedback to participants on their conduct of an HEP in the absence of a therapist. By placing the START system in the home of the participant, the perceived barriers to exercise may be reduced. START provides both audible and visual instructions to the participant, helping clarify the exercise regimen. The system uses motion capture technology to provide both real-time and post hoc feedback to the participant. The stored data are forwarded in a secure manner to the therapist, allowing remote monitoring of the participant. The data collected capture actual exercise adherence rates to report actual HEP engagement.
This case study is the foundation for ongoing research designed to test 3 propositions. First, is a sophisticated telehealth system such as START functionally and technically feasible for long periods of independent and in-home use? Second, will the system enhance HEP adherence? And third, will long-term adherence improve health outcomes? Therefore, the purpose of this case report was to (1) discuss START feasibility for in-home use and (2) describe outcomes related to START and HEP adherence rates in a 4-month intervention.
The participant was a 67-year-old woman diagnosed with PD by a neurologist 2 years before participating in this case study. Her medical history was significant for 2 lumbar compression fractures more than 40 years ago, resulting in chronic pain, a cervical fusion and laminectomy, and a paralyzed hemidiaphragm on the right from an unknown origin. Her medications included Sinemet (carbidopa-levodopa, 25/100 mg, 1 tablet, 5 × per day) for PD symptoms. She also reported taking tramadol and Tylenol III (codeine and acetaminophen) for back pain as needed.
The social history included the participant living alone. Her hobbies included reading, weaving, watching TV, volunteering at her church, and yard work. Despite attending an exercise class for people with PD twice a week, she viewed herself as sedentary with a dislike for regular exercise. She had never gone through the LSVT BIG protocol in a clinical setting but was willing to be a participant in the case study with hopes of improving her balance and helping maintain her independence. Some specific activities with which she had difficulty are as follows: (1) coming sit-to-stand from a chair without arms; (2) turning in bed; (3) walking with larger steps; (4) walking backward; and (5) getting in and out of cars.
The participant described herself as having a moderate level of computer literacy, owned her own PC, and was connected to the Internet at home. Her knowledge and use of computers did not extend beyond causal Web browsing and the use of electronic mail.
The outcomes included health-related measures, adherence to HEP, and participant satisfaction with the START system to assess use of telehealth in physical therapy practice. We also assessed specific aspects of the overall feasibility of the START system.
The health-related outcome measures were chosen for their reliability and validity in persons with PD. To provide a comprehensive and holistic approach to examination, outcome measures addressing all 4 levels of the World Health Organization's International Classification of Functioning (ICF)19,20 model were chosen. These include health condition, participation restriction, activity limitations, and body function. Hoehn and Yahr21,22 and the Unified Parkinson's Disease Rating Scale (UPDRS)23 were chosen to reflect the participant's health condition. The Parkinson's Disease Questionnaire (PDQ-39)24 broadly measures quality of life, which reflects participation restriction. The 10-m walk (10MW),25,26 the Timed Up and Go (TUG)27 test, and the Activities-specific Balance Confidence (ABC) scale26,28 give an indication of activity limitations. The 6-Minute Walk Test25,26 measures endurance, a body function.
START has the capability to track and report on actual usage by the participant. The system detects and logs each attempt to perform an exercise, so it can be used to track the number of sessions, the number of exercises attempted per session, and the number of repetitions attempted per exercise. We aggregated data from these logs to provide accurate HEP adherence measures.
System Feasibility Measures
This case study was designed to provide input into a comprehensive software feasibility analysis. We gathered data on usefulness, ease of use, and user satisfaction to assess technical and operational feasibility of the START system. At the conclusion of the case study, we conducted a semistructured interview, with questions derived from the Telemedicine Satisfaction and Usefulness Questionnaire.29 The system must also be operationally feasible, meaning that a participant must be able to operate consistently and reliably with minimal intervention from a technician. Diagnostic data indicating both proper operation and exception conditions are logged automatically with START. Support requests from the participant were documented and logged manually. These logs were used to assess operational feasibility.
Our participant presented with symptoms consistent with Hoehn and Yahr Stage II, with mild symptom severity progression as indicated by UPDRS I-III. Consistent with her self-reported concerns of balance and gait and as indicated on the ABC scale, times on the outcome measures of TUG test and 10MW indicated she was at risk for falls.30 From the PDQ-39, it was important to recognize that bodily discomfort may limit participation in LSVT BIG and the home exercises. However, because our participant was concerned about improving her balance and walking so that she could continue safely living alone, she was motivated to participate in the LSVT BIG program. LSVT BIG was chosen because of its potential effectiveness on tasks she had particular deficits in, such as walking, balance, and bed mobility.31,32 The exercise protocol required no equipment, such as a treadmill or weights, and could be done at home.
This case study was approved by the Augusta University institutional review board, and our participant gave written informed consent to participate. There were 2 components to the intervention including LSVT BIG and the START telehealth system. These are described in more detail in this section.
LSVT BIG is an exercise protocol designed specifically to target the motor symptoms of PD with high-intensity training and functional movements. It incorporates principles of motor learning31,33 and neuroplasticity by encouraging high levels of patient effort with increased intensity and amplitude of movement.34 LSVT BIG includes 16 sessions delivered over 4 weeks, with four 1-hour sessions per week. Directed exercises are coupled with an HEP, which is expected to be maintained indefinitely beyond the initial 4 weeks. Preliminary studies of LSVT BIG are promising, with participants showing improvements in gait, balance, and the motor category of UPDRS III, both immediately following the 4-week protocol31,35 and at 3 months' follow-up.35
The LSVT BIG protocol specifies 16 therapist-led sessions—four 1-hour sessions over 4 weeks. As summarized in Table 1, each session consists of 7 maximal daily exercises (2 sustained and 5 repetitive movements), 5 functional component tasks (sit-to-stand plus 4 other individualized tasks—for our participant, these included rolling, supine-to-sit, walking forward and backward, and ascending and descending steps), and BIG walking (emphasizing large, long steps and arm swing). Each session also includes 1 to 3 hierarchy tasks that were designed to be more complex and also individualized for our participant's goals (eg, enter/exit car from the passenger side to facilitate going out to lunch with friends).
During the 4-week intervention period, our participant was instructed to perform the HEP, which included the 7 maximal daily exercises as well as practice of the functional component tasks and BIG walking. She was instructed to perform the HEP twice on days that the PT did not come to her home for a therapist-led session and once on the days the PT did come for the sessions. She was also instructed to perform the exercises with the same amplitude and intensity of movement that she was encouraged to do while one-on-one with the PT.
START Telehealth System
We developed the START system adapting modern, cost-effective video game technologies to provide an in-home system to augment face-to-face physical therapy sessions. START integrates the ability to tailor a standardized rehabilitation exercise protocol to the individualized needs of a patient, interactively guide the patient through the execution of the protocol, measure the accuracy of the patient's performance, and track adherence to therapist-prescribed frequency of exercise (Figure 1).
START comprises 4 distinct software components: (1) Create; (2) Customize; (3) Train; and (4) Monitor. The Create tool is used by therapists and software specialists to design, develop, and publish new exercises and exercise protocols. The Customize tool is used by therapists to tailor each exercise movement to the capabilities of each individual if and as needed. The Train tool is the sole patient-accessible component, and it was the primary focus of this case study. Train guides the patient through the exercises and provides both real-time and post hoc feedback as to the patient's performance of each exercise. Data collected by the Train component regarding adherence and performance are securely transmitted for analysis by the patient's therapist and physician using the Monitor tool.
START Train is designed to augment a standard DVD video playback experience (ie, exercise videos). For each exercise, a model is recorded using the Create tool to provide a correct baseline of the movements required. Each exercise is broken down into individual repetitions, and each repetition further broken down into measurable poses (snapshots of the body in the proper form). Effectively working as an electronic goniometer, the tool allows each pose to be tagged with the angles that the therapist deems most critical to achieve. Once fully tagged, the repetitions and poses are sequenced such that they are fully synchronized with the DVD playback. Thus, the system can determine whether the participant is achieving a desired pose at the proper time during the DVD playback.
During playback, START Train captures the motions of the participant, compares them against the ideal form, and provides real-time feedback to the participant regarding performance. A similar system has been shown to provide feedback that matches trained PTs with a high degree of accuracy.36 For this case study, only visual feedback was provided to the participant. An unobtrusive overlay was pinned to the right of the video playback window (Figure 2) consisting of the following: (1) a gauge showing progress through the exercise and an indicator of a “score”; (2) individual indicators showing performance against each ideal pose; and (3) a silhouetted image of the participant mirroring his or her movements in real-time. The audio from the DVD itself was played without alteration or augmentation. In addition to this real-time feedback, the participant could access screens depicting performance over time as a series of drill-down charts.
All components of START are designed to run on modest, off-the-shelf computer hardware. START's Train component additionally leverages a commercially available motion capture device (Kinect; Microsoft). For this case study, the hardware installed in the patient home—including an all-in-one touchscreen PC and the Kinect—had a total cost of less than $1000. The system was provided for our participant at no cost. For this case study, the START system was configured to play the LSVT BIG Homework Helper DVD. The DVD was purchased for the participant and also provided at no cost. LSVT Global gave consent to leverage its copyrighted material in this manner for this case study.
Sequence of Intervention
Figure 3 graphically illustrates the sequence of intervention for this case study. The intervention began with therapist-led, in-home administration of the LSVT BIG protocol augmented by the START system to guide the participant through her prescribed HEP. Introduction of the START system began at the beginning of the third week of the intervention (before and during LSVT BIG session 9). This point in the protocol was chosen on the basis of the PT's clinical experience that participants seem consistently to be able to perform the LSVT BIG exercises with much less feedback after the eighth session. Location of the START system was critical, as it requires clear line of sight to a suitable area free of obstacles, approximately 2 meters (6 feet) on a side, to safely perform the exercises. The participant was able to furnish a suitable location. Installation was performed by one of the investigators and required approximately 30 minutes. Connectivity was established wirelessly using the participant's existing home Internet connection. Although the system was installed in the participant's home and physical security risks were deemed minimal, access to the system was secured using a numeric passcode that needed to be entered prior to each use.
Immediately after installation, the participant was given approximately 30 minutes of training on the use of the system. The participant then performed the entire set of exercises, recorded by START. This recording could be used by the Customize tool to tailor the movement capture system to her specific needs, although in this case, no customization was deemed necessary. She was instructed to use the system to guide her through most of her LSVT BIG HEP, including all 7 maximal daily exercises as well as “sit-to-stand.” The participant kept the system for 3 full months following the conclusion of the 4-week, therapist-led sessions. She was encouraged to continue to use the system twice a day and to continue to practice her functional tasks and BIG walking. For this case study, we were most interested in the performance of the system and its acceptance by the participant as an autonomous agent, so the therapist did not regularly monitor her data or contact her during this 3-month period.
The health-related outcome measures for this case study are summarized in Table 2. Minimal detectable change (MDC) values are provided along with an indication of whether the participant exceeded this threshold. Our participant exhibited a change that exceeded the MDC in 6MW (372 to 473 m), TUG test (14.29 to 9.07 seconds), and 10MW (1.12 to 1.59 m/s). The change observed for the ABC scale did not reach the level of MDC; however, there was initial and maintained improvement (86.1% to 95.8%). Similarly, although below MDC, her PDQ-39 scores decreased slightly from 30 to 25, indicating an improvement in her overall quality of life from the initial examination. The most noticeable change was in the category of mobility, indicating slightly more difficulty (2 points) at month 1 as compared with initial assessment. At month 4, she reported no difficulty in almost all areas of mobility, including walking a half-mile and feeling frightened or worried about falling in public. She indicated that she only occasionally needed someone to accompany her when she went out into the community.
Table 3 lists relevant usage and adherence metrics. Our participant was encouraged to perform her HEP twice per day, and her adherence to this prescription was 24%. However, the participant completed the entire HEP at least once per day 78% of the time. Adherence in month 1 was notably higher than in later months.
We also conducted a semistructured interview during the final evaluation session in month 4 to gauge the participant's satisfaction with the START system. As part of the interview, we collected verbal responses to questions derived from the Telemedicine Satisfaction and Usefulness Questionnaire.29 Her overall satisfaction with the system was high (5/5), and she felt that the system helped her manage (4/5) and monitor (5/5) her condition. She had high praise for the ease with which she was able to learn to use the system (5/5) as well as with its ease of use (5/5) and reliability (5/5). Despite some initial concern, she was satisfied that the system maintained her privacy (5/5). She felt that the lack of physical contact with a therapist was not a significant issue (5/5) and that the use of the system saved her time (5/5) when compared with attending in-person exercise sessions. In open-ended questioning, the participant indicated that she was very pleased with her overall experience with the START system. The participant did not contact the investigators with any technical issues during the intervention, nor did she note any technical issues during our questioning.
The participant did express concern regarding 2 of the system's feedback mechanisms. First, she felt that the real-time feedback received while performing exercises was somewhat confusing and provided no immediate feedback as to why she was not achieving each desired pose. Worse, because we chose simply to play the audio from the DVD itself, she heard repeated positive verbal feedback (eg, “good” and “great job”) while the system was otherwise telling her that her performance was deficient.
Second, she stated that she became discouraged by her perception of poor performance on exercises. Likely, this can be attributed to the way START measured and reported success. Only a dichotomous measure of whether a repetition of an exercise was 100% correct or not (ie, all poses were adequately similar to the ideal) was used to show successful achievement in both the real-time and post hoc feedback displays. For example, even if she correctly matched 5 out of 6 poses and was off only by a small margin on the sixth, she would receive a score of “0” on that repetition. As such, her perception of her overall performance was exceptionally poor despite performing relatively well on all exercises.
We were encouraged that our participant showed improvement in objective measures of gait and endurance, as well as self-reported confidence in balance and quality of life. An MDC was not observed for the ABC scale or for any of the dimensions of the PDQ-39; however, the trajectories were generally positive. We also noted that we would have been unlikely to observe a positive MDC, given her initial scores on the ABC scale.
If the START system were to have an impact on outcomes, it would most likely be due to one of 2 factors. First, it could have encouraged higher levels of long-term adherence. Second, it could have helped the participant conduct the exercises properly long after the initial encounter with a PT. START provides a virtual therapy assistant, demonstrating correct form and providing immediate feedback. The performance data collected by START do indicate that she continued to perform the exercises with correct amplitude and intensity of movement. START may have played a role in the maintenance of this correct form; however, without a much larger controlled study, we cannot draw any definitive conclusions.
The prescribed dosage for the HEP was 2 sessions per day, and we find only a 24% adherence rate (47% short-term and 21% long-term). This is at the lower end of self-reported adherence from prior studies. However, the participant did perform at least 1 complete HEP session on 93% of the days during the first month and on 75% thereafter. Thus, the daily participation rate was quite high and consistent with the upper range of self-reported adherence in prior studies.12,14,16 We did note that HEP participation dropped significantly after the first month, providing an opportunity for a therapist to consider ways to encourage continued participant engagement.
These adherence data compare unfavorably with some prior studies12,14; however, there are confounding factors that may help explain these findings. First, the HEP dosage for LSVT BIG (2 hours per day every day) is significantly higher.12,14,16 It seems possible that a twice-daily HEP dosage is simply too burdensome, and long-term adherence to such a program may not be a practical expectation. A future study might examine explicitly the relationships between HEP dosage, long-term adherence, and outcomes for protocols with high HEP expectations. Second, other studies rely on self-reported results15 whereas the START system collects objective measures via a motion capture system. This is a desired outcome, whereby a participant's self-report can be augmented with objective data collected using technology. It is plausible that social desirability bias may have the tendency to inflate self-reported adherence figures. Third, especially given the high dosage and the fact that our participant lived alone, it is possible that she needed reminders or some form of extrinsic motivation to continue participation at prescribed levels.
Regarding the feasibility of the START telehealth system as an HEP companion for persons with PD, this case does provide significant encouragement for further study. START was installed in the participant's home and was used for the duration of the case study without a reported technical issue. The participant received only a single, 30-minute training session and was from then on able to use the system correctly both to perform her HEP and to examine her past performance. And according to the participant, her satisfaction with the system was very high. Although the feedback from the system was at times confusing to her and may have adversely affected her experience, these concerns can be addressed with software updates. All components of the system functioned as designed, lending support to our proposition that a sophisticated telehealth system can be deployed in a home and operate consistently and reliably with limited external support for the participant. However, this finding needs to be studied in a larger trial.
Limitations and Future Direction
Although data from a single participant can provide interesting insights and individual feedback is valuable in guiding ongoing development of a tool such as START, these results are not generalizable. Furthermore, during this exploratory phase, motor outcomes were rated by the administering PT, so the validity of the measures could be questioned. And although many variables such as PD medication dosage stayed constant, many potentially influential external variables, such as additional exercise or changes to daily routine, could not be controlled. Future studies will necessarily entail a much larger number of participants and better controls during data collection.
We have already incorporated many changes designed to address the specific concerns of our participant with regard to automated feedback, but insights gained from this research have greatly expanded our understanding of the technological problems and have helped shape the future development roadmap for START.
The need to maintain motivation and remove barriers to adherence for persons requiring HEP was highlighted in this report. Perhaps, future iterations of START could be more proactive in motivating use. For example, the system could provide automated reminders via alarm or text message. Likewise, if adherence dropped consistently below goal, the system could alert the therapist or a designated caregiver to provide encouragement and support. START's Train tool is not easily moved after installation, so bringing a subset of the START functionality to mobile devices, such as phones and tablets, may also be desirable as a means of removing a barrier to use.
This case report also provided much insight into the potential need for ongoing human interaction to supplement the automated feedback provided by START. For this case study, START offered no system-mediated human interaction, such as text, audio, or video messaging to and from the PT or physician. Interview feedback from this participant would seem to support integrating this kind of human interaction. In a recent description of a study protocol37 using a telehealth system with similarities to START, regular teleconsultations with the therapist were included. When implementing a telehealth program for PT, perhaps regular scheduled contact with the therapist may provide a greater sense of ongoing human presence, increasing motivation and giving the patient an opportunity to ask questions and have the exercise program individualized. In addition, some researchers have experimented with increasing access to group exercise sessions for individuals with PD by using telepresence technology to connect a remote facility.38 A future version could add telepresence and other interactive, social capabilities to START. This could further extend the reach of group exercise sessions into individual homes and offer a more socially engaging experience.
Literature supports the notion that ongoing regular exercise has the potential to positively impact the decline of motor skills in individuals with PD. This case report seems to support past findings on the impact of exercise as part of a long-term physical therapy regimen. Especially for those who are living alone with compromised mobility, it seems critical that the exercise should be available and accessible at home. Allowing the PT to maintain ongoing visibility outside of the clinic, monitoring adherence and performance, and potentially adjusting the HEP prescription as needed present a potentially exciting opportunity to help improve and maintain the quality of life of those with neurodegenerative disorders such as PD. This case supports the notion that an in-home telehealth solution may be a viable way of extending the benefits of directed physical therapy. Future studies need to determine whether telehealth technology is cost-effective, scalable, and sustainable in the digital age. Likewise, larger studies will be needed to determine whether these results—in terms of system feasibility, adherence, and motor outcomes—can be externalized to other patients and populations. However, initial findings are encouraging and warrant further study.
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