Home-based exergaming to treat gait and balance disorders in patients with Parkinson's disease: A phase II randomized controlled trial.

BACKGROUND: Exergaming has been proposed to improve gait and balance disorders in Parkinson's disease (PD) patients. We aimed to assess the efficacy of a home-based, tailored, exergaming training system designed for PD patients with dopa-resistant gait and/or balance disorders in a controlled randomized trial. METHODS: We recruited PD patients with dopa-resistant gait and/or balance disorders. Patients were randomly assigned (1:1 ratio) to receive 18 training sessions at home by playing a tailored exergame with full-body movements using a motion capture system (Active group), or by playing the same game with the computer's keyboard (Control group). The primary endpoint was the between-group difference in the Stand-Walk-Sit Test (SWST) duration change after training. Secondary outcomes included parkinsonian clinical scales, gait recordings, and safety. RESULTS: Fifty PD patients were enrolled and randomized. After training, no significant difference in SWST change was found between groups (mean change SWST duration [SD] -3.71 [18.06] s after Active versus -0.71 [3.41] s after Control training, p = 0.61). Some 32% of patients in the Active and 8% in the Control group were considered responders to the training program (e.g., SWST duration change ≥2 s, p = 0.03). The clinical severity of gait and balance disorders also significantly decreased after Active training, with a between-group difference in favor of the Active training (p = 0.0082). Home-based training induced no serious adverse events. CONCLUSIONS: Home-based training using a tailored exergame can be performed safely by PD patients and could improve gait and balance disorders. Future research is needed to investigate the potential of exergaming.

Study protocol for the MIND-PD study: a randomized controlled trial to investigate clinical and biological effects of mindfulness-based cognitive therapy in people with Parkinson's disease.

BACKGROUND: People with Parkinson's disease (PD) are very sensitive to the effects of stress. The prevalence of stress-related neuropsychiatric symptoms is high, and acute stress worsens motor symptoms. Animal studies suggest that chronic stress may accelerate disease progression, but evidence for this in humans is lacking. Mindfulness-based interventions (MBIs) train participants to focus on the present moment, on purpose and without judgement. Previous studies suggest that MBIs may alleviate stress and reduce depression and anxiety in PD. We aim to demonstrate the efficacy of Mindfulness-Based Cognitive Therapy (MBCT) as a non-pharmacologic treatment strategy for neuropsychiatric (and motor) symptoms in PD, and to identify the mechanisms underlying stress and stress reduction in PD. METHODS: In a prospective randomized controlled trial (RCT), we investigate whether 8 weeks of MBCT, as compared to care as usual, can reduce symptoms of anxiety and depression in people with PD. We aim to include 124 PD patients, who experience mild-moderate symptoms of anxiety and depression, are eligible for magnetic resonance imaging (MRI) and naïve to mindfulness, and who have a disease duration ≤ 10 years. Every participant is followed for 12 months. Clinical and biochemical assessments take place at baseline (T0), after 2 months (T1), and after 12 months (T2); MRI assessments take place at T0 and T2. Our primary outcome is the total score on the Hospital Anxiety and Depression Scale (HADS) at T1, while correcting for the HADS score at T0, age, and gender. Beyond testing the effects of MBCT on symptoms of anxiety and depression in PD, we explore whether MBCT: (1) has an effect on motor symptom severity, (2) influences cerebral and biochemical markers of stress, and (3) leads to a change in biomarkers of PD progression. DISCUSSION: MIND-PD is one of the first RCTs with a 1-year follow-up to investigate the effects of MBCT on symptoms of anxiety and depression in PD, and to explore possible mechanisms underlying stress and stress reduction in PD. Insight into these mechanisms can pave the way to new treatment methods in the future. TRIAL REGISTRATION: ClinicalTrials.gov, NCT05779137. Registered on 12 January 2023.

Study protocol for the Heads-Up trial: a phase II randomized controlled trial investigating head-up tilt sleeping to alleviate orthostatic intolerance in Parkinson's Disease and parkinsonism.

BACKGROUND: In persons with Parkinson's Disease (PD) or certain forms of atypical parkinsonism, orthostatic hypotension is common and disabling, yet often underrecognized and undertreated. About half of affected individuals also exhibit supine hypertension. This common co-occurrence of both orthostatic hypotension and supine hypertension complicates pharmacological treatments as the treatment of the one can aggravate the other. Whole-body head-up tilt sleeping (HUTS) is the only known intervention that may improve both. Evidence on its effectiveness and tolerability is, however, lacking, and little is known about the implementability. METHODS: In this double-blind multicenter randomized controlled trial (phase II) we will test the efficacy and tolerability of HUTS at different angles in 50 people with PD or parkinsonism who have both symptomatic orthostatic hypotension and supine hypertension. All participants start with one week of horizontal sleeping and subsequently sleep at three different angles, each maintained for two weeks. The exact intervention will vary between the randomly allocated groups. Specifically, the intervention group will consecutively sleep at 6°, 12° and 18°, while the delayed treatment group starts with a placebo angle (1°), followed by 6° and 12°. We will evaluate tolerability using questionnaires and compliance to the study protocol. The primary endpoint is the change in average overnight blood pressure measured by a 24-hour ambulatory blood pressure recording. Secondary outcomes include orthostatic blood pressure, orthostatic tolerance, supine blood pressure, nocturia and various other motor and non-motor tests and questionnaires. DISCUSSION: We hypothesize that HUTS can simultaneously alleviate orthostatic hypotension and supine hypertension, and that higher angles of HUTS are more effective but less tolerable. The Heads-Up trial will help to clarify the effectiveness, tolerability, and feasibility of this intervention at home and can guide at-home implementation. TRIAL REGISTRATION: ClinicalTrials.gov NCT05551377; Date of registration: September 22, 2022.

Aerobic Exercise Alters Brain Function and Structure in Parkinson's Disease: A Randomized Controlled Trial.

OBJECTIVE: Randomized clinical trials have shown that aerobic exercise attenuates motor symptom progression in Parkinson's disease, but the underlying neural mechanisms are unclear. Here, we investigated how aerobic exercise influences disease-related functional and structural changes in the corticostriatal sensorimotor network, which is involved in the emergence of motor deficits in Parkinson's disease. Additionally, we explored effects of aerobic exercise on tissue integrity of the substantia nigra, and on behavioral and cerebral indices of cognitive control. METHODS: The Park-in-Shape trial is a single-center, double-blind randomized controlled trial in 130 Parkinson's disease patients who were randomly assigned (1:1 ratio) to aerobic exercise (stationary home trainer) or stretching (active control) interventions (duration = 6 months). An unselected subset from this trial (exercise, n = 25; stretching, n = 31) underwent resting-state functional and structural magnetic resonance imaging (MRI), and an oculomotor cognitive control task (pro- and antisaccades), at baseline and at 6-month follow-up. RESULTS: Aerobic exercise, but not stretching, led to increased functional connectivity of the anterior putamen with the sensorimotor cortex relative to the posterior putamen. Behaviorally, aerobic exercise also improved cognitive control. Furthermore, aerobic exercise increased functional connectivity in the right frontoparietal network, proportionally to fitness improvements, and it reduced global brain atrophy. INTERPRETATION: MRI, clinical, and behavioral results converge toward the conclusion that aerobic exercise stabilizes disease progression in the corticostriatal sensorimotor network and enhances cognitive performance. ANN NEUROL 2022;91:203-216.

Specialized Versus Generic Allied Health Therapy and the Risk of Parkinson's Disease Complications.

BACKGROUND: Specialized versus generic physiotherapy (PT) reduces Parkinson's disease (PD)-related complications. It is unclear (1) whether other specialized allied heath disciplines, including occupational therapy (OT) and speech and language therapy (S<), also reduce complications; (2) whether there is a synergistic effect among multiple specialized disciplines; and (3) whether each allied health discipline prevents specific complications. OBJECTIVES: To longitudinally assessed whether the level of expertise (specialized vs. generic training) of PT, OT, and S< was associated with the incidence rate of PD-related complications. METHODS: We used claims data of all insured persons with PD in the Netherlands between January 1, 2010, and December 31, 2018. ParkinsonNet-trained therapists were classified as specialized, and other therapists as generic. We used mixed-effects Poisson regression models to estimate rate ratios adjusting for sociodemographic and clinical characteristics. RESULTS: The population of 51,464 persons with PD (mean age, 72.4 years; standard deviation 9.8) sustained 10,525 PD-related complications during follow-up (median 3.3 years). Specialized PT was associated with fewer complications (incidence rate ratio [IRR] of specialized versus generic = 0.79; 95% confidence interval, [0.74-0.83]; P < 0.0001), as was specialized OT (IRR = 0.88 [0.77-0.99]; P = 0.03). We found a trend of an association between specialized S< and a lower rate of PD-related complications (IRR = 0.88 [0.74-1.04]; P = 0.18). The inverse association of specialized OT persisted in the stratum, which also received specialized PT (IRR = 0.62 [0.42-0.90]; P = 0.001). The strongest inverse association of PT was seen with orthopedic injuries (IRR = 0.78 [0.73-0.82]; P < 0.0001) and of S< with pneumonia (IRR = 0.70 [0.53-0.93]; P = 0.03). CONCLUSIONS: These findings support a wider introduction of specialized allied health therapy expertise in PD care and conceivably for other medical conditions. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

The STEPWISE study: study protocol for a smartphone-based exercise solution for people with Parkinson's Disease (randomized controlled trial).

BACKGROUND: Exercise has various health benefits for people with Parkinson's disease (PD). However, implementing exercise into daily life and long-term adherence remain challenging. To increase a sustainable engagement with physical activity of people with PD, interventions that are motivating, accessible, and scalable are needed. We primarily aim to investigate whether a smartphone app (STEPWISE app) can increase physical activity (i.e., step count) in people with PD over one year. Our second aim is to investigate the potential effects of the intervention on physical fitness, and motor- and non-motor function. Our third aim is to explore whether there is a dose-response relationship between volume of physical activity and our secondary endpoints. METHODS: STEPWISE is a double-blind, randomized controlled trial. We aim to include 452 Dutch people with PD who can walk independently (Hoehn & Yahr stages 1-3) and who do not take more than 7,000 steps per day prior to inclusion. Physical activity levels are measured as step counts on the participant's own smartphone and scaled as percentage of each participant's baseline. Participants are randomly assigned to an active control group with an increase of 5-20% (active controls) or any of the three intervention arms with increases of 25-100% (intermediate dose), 50-200% (large dose), or 100-400% (very large dose). The primary endpoint is change in step count as measured by the STEPWISE smartphone app from baseline to 52 weeks. For our primary aim, we will evaluate the between-group difference in average daily step count change from baseline to 52 weeks. For our second aim, measures of physical fitness, and motor- and non-motor function are included. For our third aim, we will associate 52-week changes in step count with 52-week changes in secondary outcomes. DISCUSSION: This trial evaluates the potential of a smartphone-based intervention to increase activity levels in people with PD. We envision that motivational apps will increase adherence to physical activity recommendations and could permit conduct of remote clinical trials of exercise for people with PD or those at risk of PD. TRIAL REGISTRATION: ClinicalTrials.gov; NCT04848077; 19/04/2021. CLINICALTRIALS: gov/ct2/show/NCT04848077.

Exercise Made Accessible: the Merits of Community-Based Programs for Persons with Parkinson's Disease.

PURPOSE OF REVIEW: Many studies have identified positive effects of physiotherapy and exercise for persons with Parkinson's disease (PD). Most work has thus far focused on the therapeutic modality of exercise as used within physiotherapy programs. Stimulated by these positive findings, there is now a strong move to take exercise out of the clinical setting and to deliver the interventions in the community. Although the goals and effects of many such community-based exercise programs overlap with those of physiotherapy, it has also become more clear that both exercise modalities also differ in various ways. Here, we aim to comprehensively review the evidence for community-based exercise in PD. RECENT FINDINGS: Many different types of community-based exercise for people with PD are emerging and they are increasingly being studied. There is a great heterogeneity considering the types of exercise, study designs, and outcome measures used in research on this subject. While this review is positive regarding the feasibility and potential effects of community-based exercise, it is also evident that the general quality of these studies needs improvement. By focusing on community-based exercise, we hope to generate more knowledge on the effects of a wide range of different exercise modalities that can be beneficial for people with PD. This knowledge may help people with PD to select the type and setting of exercise activity that matches best with their personal abilities and preferences. As such, these insights will contribute to an improved self-management of PD.

Home-based monitoring of falls using wearable sensors in Parkinson's disease.

INTRODUCTION: Falling is among the most serious clinical problems in Parkinson's disease (PD). We used body-worn sensors (falls detector worn as a necklace) to quantify the hazard ratio of falls in PD patients in real life. METHODS: We matched all 2063 elderly individuals with self-reported PD to 2063 elderly individuals without PD based on age, gender, comorbidity, and living conditions. We analyzed fall events collected at home via a wearable sensor. Fall events were collected either automatically using the wearable falls detector or were registered by a button push on the same device. We extracted fall events from a 2.5-year window, with an average follow-up of 1.1 years. All falls included were confirmed immediately by a subsequent telephone call. The outcomes evaluated were (1) incidence rate of any fall, (2) incidence rate of a new fall after enrollment (ie, hazard ratio), and (3) 1-year cumulative incidence of falling. RESULTS: The incidence rate of any fall was higher among self-reported PD patients than controls (2.1 vs. 0.7 falls/person, respectively; P < .0001). The incidence rate of a new fall after enrollment (ie, hazard ratio) was 1.8 times higher for self-reported PD patients than controls (95% confidence interval, 1.6-2.0). CONCLUSION: Having PD nearly doubles the incidence of falling in real life. These findings highlight PD as a prime "falling disease." The results also point to the feasibility of using body-worn sensors to monitor falls in daily life. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Feasibility of a Cognitive Training Game in Parkinson's Disease: The Randomized Parkin'Play Study.

Cognitive training (CT) shows modest positive effects on cognitive function in patients with Parkinson's disease (PD). Gamification may enhance adherence to traditional CT, but this has not been studied yet. Here, we investigated the feasibility of a gamified CT. We performed a randomized controlled trial including PD patients with mild cognitive impairment. Participants were randomly allocated to a 12-week home-based gamified CT intervention or waiting-list control group. Assessments were performed at baseline and at weeks 12 and 24. Forty-one patients were included (21 intervention and 20 waiting-list controls). Sixty-three percent of the intervention group trained >50% of the recommended sessions, while 81% voluntarily continued training after 12 weeks. After 24 weeks, 87.5% graded the game to be satisfactory. Global cognition scores improved after 24 weeks. Home-based gamified CT shows acceptable feasibility in patients with PD, and we observed preliminary indications for efficacy. Larger trials are needed to establish this efficacy.

Towards seeing the visual impairments in Parkinson's disease: protocol for a multicentre observational, cross-sectional study.

BACKGROUND: Visual disorders are common in Parkinson's disease (PD) but their exact frequency and severity are unknown. Good visual functioning is crucial for patients with PD, because of their need to compensate for loss of automated motor control and their postural instability, forcing patients to guide their movements visually. Here, we describe the study design of a cross-sectional, multi-centre study aiming to: (1) validate the Visual Impairment screening questionnaire (VIPD-Q, which aims to identify PD patients who should be referred to an ophthalmologist for further assessment); (2) study the prevalence of visual disorders in PD; (3) study the severity and clinical impact of different types of visual disorders in PD; and (4) explore treatment options for ophthalmologic disorders in PD, as a basis for future guideline development. METHODS: This study consists of two phases. In phase one, 750 PD patients and 250 healthy controls will be recruited to complete the VIPD-Q. In phase two, a subgroup of responders (n = 100) (with the highest and lowest scores on the VIPD-Q) will be invited for an extensive neurological and ophthalmological assessment. The in-depth ophthalmologic examination will serve as the "gold standard" for validating the VIPD-Q. Moreover, these assessments will be used to study associations between visual disorders and clinical presentation, in order to gain more insight in their clinical impact. DISCUSSION: Our study will heighten the awareness of visual problems in PD and offers a robust starting point to systematically approach this subject. In current daily practice, the association between visual problems and PD is far from obvious to both patients and clinicians. Consequently, patients may not adequately report visual problems themselves, while clinicians miss potentially treatable visual disorders. Routinely asking patients to complete a simple screening questionnaire could be an easy solution leading to timely identification of visual problems, tailored treatment, restored mobility, greater independence and improved quality of life. TRIAL REGISTRATION: Dutch Trial Registration, NL7421 , Registered on 4 December 2018 - Retrospectively registered.

Physical therapy and occupational therapy in Parkinson's disease.

Current medical management is only partially effective in controlling the symptoms of Parkinson's disease. As part of comprehensive multidisciplinary care, physical therapy and occupational therapy aim to support people with Parkinson's disease in dealing with the consequences of their disease in daily activities. In this narrative review, we address the limitations that people with Parkinson's disease may encounter despite optimal medical management, and we clarify both the unique and shared approaches that physical therapists and occupational therapists can apply in treating these limitations.

Unmasking levodopa resistance in Parkinson's disease.

Some motor and nonmotor features associated with Parkinson's disease (PD) do not seem to respond well to levodopa (or other forms of dopaminergic medication) or appear to become resistant to levodopa treatment with disease progression and longer disease duration. In this narrative review, we elaborate on this issue of levodopa resistance in PD. First, we discuss the possibility of pseudoresistance, which refers to dopamine-sensitive symptoms or signs that falsely appear to be (or have become) resistant to levodopa, when in fact other mechanisms are at play, resulting in suboptimal dopaminergic efficacy. Examples include interindividual differences in pharmacodynamics and pharmacokinetics and underdosing because of dose-limiting side effects or because of levodopa phobia. Moreover, pseudoresistance can emerge as not all features of PD respond adequately to the same dosage of levodopa. Second, we address that for several motor features (eg, freezing of gait or tremor) and several nonmotor features (eg, specific cognitive functions), the response to levodopa is fairly complex, with a combination of levodopa-responsive, levodopa-resistant, and even levodopa-induced characteristics. A possible explanation relates to the mixed presence of underlying dopaminergic and nondopaminergic brain lesions. We suggest that clinicians take these possibilities into account before concluding that symptoms or signs of PD are totally levodopa resistant. © 2016 International Parkinson and Movement Disorder Society.

Nonpharmacological treatments for patients with Parkinson's disease.

Since 2013, a number of studies have enhanced the literature and have guided clinicians on viable treatment interventions outside of pharmacotherapy and surgery. Thirty-three randomized controlled trials and one large observational study on exercise and physiotherapy were published in this period. Four randomized controlled trials focused on dance interventions, eight on treatment of cognition and behavior, two on occupational therapy, and two on speech and language therapy (the latter two specifically addressed dysphagia). Three randomized controlled trials focused on multidisciplinary care models, one study on telemedicine, and four studies on alternative interventions, including music therapy and mindfulness. These studies attest to the marked interest in these therapeutic approaches and the increasing evidence base that places nonpharmacological treatments firmly within the integrated repertoire of treatment options in Parkinson's disease.

Design of the Park-in-Shape study: a phase II double blind randomized controlled trial evaluating the effects of exercise on motor and non-motor symptoms in Parkinson's disease.

BACKGROUND: Parkinson's disease (PD) is a neurodegenerative disorder with a wide range of motor and non-motor symptoms. Despite optimal medical management, PD still results in a high disability rate and secondary complications and many patients lead a sedentary lifestyle, which in turn is also associated with a higher co-morbidity and mortality. Exercise has been explored as a strategy to reduce secondary complications and results suggests that it not only provides general health benefits, but may also provide symptomatic relief. If this holds true exercise would be a very attractive addition to the therapeutic arsenal in PD. The supportive evidence remains incomplete. Here, we describe the design of the Park-in-Shape study, which primarily aims to evaluate whether aerobic exercise affords clinically relevant improvements in motor symptoms in sedentary PD patients. A specific new element is the introduction of gaming to optimize compliance to the exercise intervention. METHODS/DESIGN: The Park-in-Shape study is a randomized controlled, assessor- and patient-blinded single center study. Two parallel groups will include a total of 130 patients, receiving either aerobic exercise on a home trainer equipped with gaming elements ("exergaming"), or a non-aerobic intervention (stretching, flexibility and relaxation exercises). Both groups are supported by a specifically designed motivational app that uses gaming elements to stimulate patients to exercise and rewards them after having completed the exercise. Both interventions are delivered at home at least 3 times a week for 30-45 minutes during 6 months. Eligible patients are community-dwelling, sedentary patients diagnosed with mild-moderate PD. The primary outcome is the MDS-UPDRS motor score (tested in the off state) after 6 months. Secondary outcomes include various motor and non-motor symptoms, quality of life, physical fitness, and adherence. DISCUSSION: This Park-in-Shape study is anticipated to answer the question whether high intensity aerobic exercise combined with gaming elements ("exergaming") provides symptomatic relief in PD. Strong elements include the double-blinded randomized controlled trial design, the MDS-UPDRS as valid primary outcome, the large sample size and unique combination of home-based pure aerobic exercise combined with gaming elements and motivational aspects. TRIAL REGISTRATION: Dutch trial register NTR4743.

Dietary Interventions in Parkinson's Disease.

Several dietary patterns and nutritional supplements have been linked to the development, progression, and symptomatic treatment of Parkinson's disease (PD). Most of the evidence, at this point, is preliminary and based largely on observational studies. Interventional studies are scarce, so the evidence on effectiveness remains inconclusive. Dietary interventions could, analogous to exercise, potentially have a beneficial effect on disease symptoms as well as on the progression of the disease and should therefore be researched in high quality studies. Further work is also needed to study whether dietary interventions, when applied to an at-risk population, have any potential to postpone the onset of manifest PD. In this paper, we summarize all ongoing clinical trials on dietary interventions in PD. We found 10 ongoing studies, all aimed at a different intervention. These studies are mostly exploratory in nature or represent phase I or phase II trials focusing on safety, biological responses, and symptomatic effects. Taken together, we conclude that research on dietary interventions in persons with PD is still in its early days. The results of the various ongoing trials are expected to generate new hypotheses and will help to shape the agenda for future research on this important topic.

The value of consciousness coaching in Parkinson's disease: Experiences and possible impact of holistic coaching.

Background: People with a chronic condition such as Parkinson's disease (PD) struggle with acceptance and finding meaning in life. Consciousness coaching could be a valuable addition in addressing these issues. Objective: We aim to evaluate the user experiences and potential effectiveness of consciousness coaching for people with PD (PwPD). Methods: We performed a pilot randomized controlled trial including PwPD in Hoehn & Yahr stage 1-3. People with cognitive impairments, severe psychiatric disorders, or those who did not have a clear issue to address with consciousness coaching, were excluded. PwPD were randomly allocated to either receiving 6 months of consciousness coaching in addition to usual care or to usual care alone. To explore experiences we performed semi-structured qualitative interviews with all PwPD in the intervention group. Potential effects were explored using questionnaires on quality of life, activities of daily life, self-management and non-motor symptoms at baseline and after 6 months. Results: We included 39 PwPD, 19 participants in the intervention group and 20 in the control group. Based on the interviews, we identified a number of themes and codes. In general PwPD experienced consciousness coaching as confronting but supportive in reaching their goals and in taking more responsibility for their lives. Quantitatively, we did not find a difference between groups for any of the outcomes. Conclusions: Consciousness coaching was considered valuable by most participants in this study and may be an interesting addition to PD treatment. We did not find any effects of the intervention on PD symptoms or quality of life.

Natural Health Products for Symptomatic Relief of Parkinson's Disease: Prevalence, Interest, and Awareness.

Background: Natural health products have emerged as a potential symptomatic therapeutic approach for people with Parkinson's disease (PD). Objective: To determine the prevalence of natural health product use, interest in natural health products, awareness of potential herb-drug interactions, and consultation of healthcare professionals regarding natural health products use among people with PD. Methods: Cross-sectional 4-item survey embedded in the PRIME-NL study, which is a population-based cohort of PD. Results: Of 367 people with PD, 36% reported having used natural health products to alleviate PD-related symptoms, with coffee, cannabis and turmeric being the most popular. Furthermore, 71% of people with PD were interested in learning more about natural health products. 39% of natural health products users were aware that these products could interact with PD medication and 39% had discussed their use with their healthcare professional. Conclusions: Natural health products are commonly used to alleviate symptoms by people with PD, but most users are unaware that these products can interact with PD medication and do not discuss their consumption with their healthcare professional.

Parkinson's disease is a complex neurodegenerative disorder for which current treatments are limited to symptomatic relief, and prescribed medication often causes side effects. In this context, there is an increasing interest in non-pharmacological interventions, and people living with Parkinson's disease may want to explore natural health products to alleviate disease-associated symptoms. Examples of these products include cannabis, coffee, or velvet bean (as a natural source of Levodopa). However, it remains unclear how many people with Parkinson's disease have ever used, or wish to use, natural health products to relieve disease-related symptoms. In addition, limited information is available to evaluate whether they are aware of possible interactions between these products and prescribed medication. Therefore, the aim of this study was to investigate these questions in a large representative group of people with Parkinson's disease. A total of 367 people responded to the survey, and 36% reported that they had used natural health products to relieve Parkinson's disease-related symptoms. Among the supplements listed in our survey, coffee (16%), cannabis (13%) and turmeric (10%) were the most popular. Additionally, 71% of participants were interested in learning more about natural health products, and we found that 39% of natural health product users were aware of possible interactions with prescribed Parkinson's disease medication. However, it appeared that only 39% of users had discussed these supplements with their healthcare provider. These observations are important because a concern regarding the integration of natural health products into clinical practice is their potential interactions with prescribed medication. Therefore, these findings support the need for additional research efforts into the health benefits and safety of these products. We conclude that natural health products are used by people with Parkinson's disease to provide symptomatic relief, and open discussions with their healthcare providers are encouraged to ensure efficacy and safety.

Guide to Decomposition of Causal Effects Into Mediation, Interaction, and Direct Effects: Case Study on Aerobic Exercise and Parkinson Disease.

Mediation analysis can be applied in medical research with the aim of understanding the pathways that operate between an exposure and its effects on an outcome. This method can help to improve our understanding of pathophysiologic mechanisms and may guide the choice of potential treatment strategies. Traditional mediation analysis decomposes the total effect of an intervention on the outcome into 2 effects: (1) an indirect effect, from exposure using a mediator to the outcome, and (2) a direct effect, directly from exposure to outcome. A limitation of this method is that it assumes no interaction between the exposure and the mediator, which can either lead to an over- or underestimation of clinically relevant effects. The "4-way decomposition" method has the advantage of overcoming this limitation. Specifically, the total effect of an exposure on the outcome is decomposed into 4 elements: (1) reference interaction (interaction only), (2) mediated interaction (mediation and interaction), (3) the pure indirect effect (mediation but not interaction), and (4) the direct effect (no mediation and no interaction). We provide a guide to select the most appropriate method to investigate and decompose any causal effect given the research question at hand. We explain the application of the 4-way decomposition and illustrate this with a real-world example of how aerobic exercise may influence motor function in persons with Parkinson disease.

The sound of Parkinson's disease: A model of audible bradykinesia.

INTRODUCTION: Evaluation of bradykinesia is based on five motor tasks from the MDS-UPDRS. Visually scoring these motor tasks is subjective, resulting in significant interrater variability. Recent observations suggest that it may be easier to hear the characteristic features of bradykinesia, such as the decrement in sound intensity or force of repetitive movements. The objective is to evaluate whether audio signals derived during four MDS-UPDRS tasks can be used to detect and grade bradykinesia, using two machine learning models. METHODS: 54 patients with Parkinson's disease and 28 healthy controls were filmed while executing the bradykinesia motor tasks. Several features were extracted from the audio signal, including number of taps, speed, sound intensity, decrement and freezes. For each motor task, two supervised machine learning models were trained, Logistic Regression (LR) and Support Vector Machine (SVM). RESULTS: Both classifiers were able to separate patients from controls reasonably well for the leg agility task, area under the receiver operating characteristic curve (AUC): 0.92 (95%CI: 0.78-0.99) for LR and 0.93 (0.81-1.00) for SVM. Also, models were able to differentiate less severe bradykinesia from severe bradykinesia, particularly for the pronation-supination motor task, with AUC: 0.90 (0.62-1.00) for LR and 0.82 (0.45-0.97) for SVM. CONCLUSION: This audio-based approach discriminates PD from healthy controls with moderate-high accuracy and separated individuals with less severe bradykinesia from those with severe bradykinesia. Sound analysis may contribute to the identification and monitoring of bradykinesia.

Measuring Physical Functioning Using Wearable Sensors in Parkinson Disease and Chronic Obstructive Pulmonary Disease (the Accuracy of Digital Assessment of Performance Trial Study): Protocol for a Prospective Observational Study.

BACKGROUND: Physical capacity and physical activity are important aspects of physical functioning and quality of life in people with a chronic disease such as Parkinson disease (PD) or chronic obstructive pulmonary disease (COPD). Both physical capacity and physical activity are currently measured in the clinic using standardized questionnaires and tests, such as the 6-minute walk test (6MWT) and the Timed Up and Go test (TUG). However, relying only on in-clinic tests is suboptimal since they offer limited information on how a person functions in daily life and how functioning fluctuates throughout the day. Wearable sensor technology may offer a solution that enables us to better understand true physical functioning in daily life. OBJECTIVE: We aim to study whether device-assisted versions of 6MWT and TUG, such that the tests can be performed independently at home using a smartwatch, is a valid and reliable way to measure the performance compared to a supervised, in-clinic test. METHODS: This is a decentralized, prospective, observational study including 100 people with PD and 100 with COPD. The inclusion criteria are broad: age ≥18 years, able to walk independently, and no co-occurrence of PD and COPD. Participants are followed for 15 weeks with 4 in-clinic visits, once every 5 weeks. Outcomes include several walking tests, cognitive tests, and disease-specific questionnaires accompanied by data collection using wearable devices (the Verily Study Watch and Modus StepWatch). Additionally, during the last 10 weeks of this study, participants will follow an aerobic exercise training program aiming to increase physical capacity, creating the opportunity to study the responsiveness of the remote 6MWT. RESULTS: In total, 89 people with PD and 65 people with COPD were included in this study. Data analysis will start in April 2024. CONCLUSIONS: The results of this study will provide information on the measurement properties of the device-assisted 6MWT and TUG in the clinic and at home. When reliable and valid, this can contribute to a better understanding of a person's physical capacity in real life, which makes it possible to personalize treatment options. TRIAL REGISTRATION: ClinicalTrials.gov NCT05756075; https://clinicaltrials.gov/study/NCT05756075. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/55452.