EMST with SpiroGym App for Parkinson's Disease (NCT06942533)

Overview

Overview

This clinical trial investigates the effects of visual feedback from the SpiroGym mobile application on Expiratory Muscle Strength Training (EMST) performance in patients with [Parkinson's Disease](/diseases/parkinsons-disease). The study is conducted at the General University Hospital in Prague, Czechia, and represents an innovative approach to addressing respiratory dysfunction in [Parkinson's disease](/diseases/parkinsons-disease) patients through device-assisted breathing exercises.

Trial Details

| Parameter | Value |
|-----------|-------|
| NCT Number | NCT06942533 |
| Title | The Effect of Visual Feedback From the SpiroGym Mobile Application on Expiratory Muscle Strength Training Performance in Patients With Parkinson's Disease |
| Brief Title | Effect of Visual Feedback From the SpiroGym Mobile Application |
| Status | Recruiting |
| Phase | Not Applicable |
| Study Type | Interventional |
| Enrollment | 30 participants |
| Sponsor | General University Hospital, Prague |
| Start Date | May 1, 2025 |
| Completion Date | July 1, 2026 |
| Locations | Prague, Czechia |

Primary Outcome Measures

Scientific Rationale

Respiratory Dysfunction in Parkinson's Disease

Respiratory dysfunction is a common and often underappreciated complication of Parkinson's disease, affecting up to 50-90% of patients across various disease stages. This dysfunction manifests through multiple mechanisms:

1. Muscle Weakness

• Diaphragmatic weakness: The diaphragm, the primary muscle of inspiration, shows reduced contractile force in PD patients
• Abdominal muscle impairment: Expiratory muscles including the internal and external obliques, transversus abdominis, and rectus abdominis demonstrate decreased strength
• Accessory muscle dysfunction: Secondary respiratory muscles show early fatigue and reduced efficiency

2. Airway Protection Deficits

Parkinson's disease affects the coordinated muscle activity required for effective cough:

• Reduced cough flow: Peak expiratory flow during cough is significantly diminished
• Impaired glottic closure: Incomplete vocal cord adduction reduces cough effectiveness
• Secretion retention: Inability to clear secretions leads to recurrent respiratory infections

3. Autonomic Contributions

The autonomic nervous system dysfunction in PD extends to respiratory control, affecting the [autonomic nervous system](/entities/autonomic-nervous-system):

• Reduced respiratory drive: Central autonomic impairment affects baseline respiratory effort
• Abnormal breathing patterns: Irregular breathing rhythms and reduced variability
• Dysregulated airway tone: Altered autonomic control of bronchial smooth muscle

Expiratory Muscle Strength Training (EMST)

EMST is a targeted rehabilitation technique designed to improve expiratory muscle function through progressive resistance training. The approach is grounded in the principle of overload and specificity:

Mechanism of Action

Evidence Base

EMST has demonstrated efficacy in multiple populations:

• Parkinson's disease: Studies show improved cough strength, swallow function, and voice outcomes
• Multiple System Atrophy: Benefits respiratory function and reduces aspiration risk
• Healthy elderly: Improves age-related decline in respiratory muscle function
• Neurological conditions: Effective in stroke, ALS, and traumatic brain injury

SpiroGym Mobile Application

The SpiroGym system represents a novel integration of traditional EMST with digital health technology:

Device Components

How SpiroGym Works

During correct performance of the expiratory manoeuvre with the handheld device:

• The exhalation valve opens and the resulting airflow increases the sound level detected by the smartphone microphone
• The application provides real-time visual feedback on the mobile phone screen as a curve depicting the current sound level
• The patient's task is to keep the curve within the training zone, defined by two lines corresponding to the lower and upper thresholds

Innovation in This Trial

The key innovation in NCT06942533 is the investigation of visual feedback's impact on training outcomes:

• Real-time Monitoring: Users see their expiratory sound intensity in real-time
• Goal Visualization: Target zones and progress toward goals displayed graphically
• Performance Tracking: Historical data visualization encourages adherence
• Biofeedback Potential: Visual cues may enhance motor learning and muscle recruitment

Connection to Parkinson's Disease Pathology

Alpha-Synuclein and Respiratory Centers

While primarily considered a motor disorder, Parkinson's disease affects multiple brainstem nuclei that control respiration through the accumulation of [alpha-synuclein](/proteins/alpha-synuclein):

• Dorsal respiratory group: Located in the medulla, affected by alpha-synuclein deposition
• Ventral respiratory group: Coordinates accessory muscle activity during forced expiration
• Pneumotaxic center: Located in the pons, regulates breathing rhythm

Lewy Body Pathology in Respiratory Pathways

Research demonstrates that Lewy bodies (aggregated alpha-synuclein) are present in:

• Brainstem respiratory nuclei
• Peripheral autonomic [neurons](/entities/neurons) controlling airway smooth muscle
• Enteric nervous system afferents that modulate respiratory reflexes

Clinical Implications

Respiratory dysfunction in PD contributes to:

Study Design

Intervention Protocol

The trial employs a prospective crossover design:

• Device: EMST150 pressure threshold trainer (Aspire Products, LLC)
• Application: SpiroGym mobile [app](/entities/app-protein) for visual feedback (when assigned)
• Protocol: Five sets of five forceful expirations at 75% of maximum expiratory pressure (MEP)
• Duration: Each session conducted at baseline and week 2 (separated by two-week interval)

Crossover Design

Each PD patient completes two EMST sessions:

The order is randomly assigned. This allows each participant to serve as their own control.

Assessment Methodology

Surface Electromyography (sEMG)

The primary outcome measure uses sEMG to assess muscle activation:

• Target Muscles:
• Internal oblique abdominis (m. obliquus internus abdominis) — primary
• Rectus abdominis (m. rectus abdominis)
• External oblique abdominis (m. obliquus externus abdominis)
• Suprahyoid muscle complex
• Measurement: Wireless electrodes placed on clean skin; Reference Voluntary Contraction (RVC) used for normalization
• Analysis: Comparison of sEMG amplitude between EMST with vs. without SpiroGym conditions

SpiroGym Sound Intensity (SSI)

Secondary outcome measures the intensity of sound generated:

• Principle: Louder sound indicates greater expiratory force
• Comparison: SSI values during EMST with vs. without visual feedback

Participant Feedback Questionnaire

Secondary outcome assessing:

• Perceived exercise difficulty (Likert scale)
• Motivation to perform exercises with vs. without visual feedback

Eligibility Criteria

Inclusion:

• Diagnosis of Parkinson's disease
• Stable dopaminergic medication (stable dose for at least 1 month)

• Other neurological disorders
• Significant cognitive impairment
• Major psychiatric disorder
• History of head or neck cancer or previous surgical interventions in the neck region
• Illness during the study period

Expected Outcomes

This trial aims to establish whether visual feedback enhances EMST effectiveness:

| Hypothesis | Expected Result |
|------------|-----------------|
| sEMG activation | Greater muscle activation with visual feedback |
| SSI values | Higher sound intensity (expiratory force) with feedback |
| Perceived difficulty | Lower difficulty with visual feedback |
| Motivation | Higher motivation with visual feedback |

The previous pilot study showed that two weeks of intensive EMST with SpiroGym was sufficient to significantly improve voluntary peak cough flow (PCF), with improvement quantitatively comparable to that reported in other intensive EMST studies of longer duration.

Relevance to Parkinson's Disease Therapeutics

This trial represents the intersection of rehabilitation medicine and digital health, testing an innovative approach to addressing respiratory dysfunction in PD:

| Approach | Stage | Mechanism |
|----------|-------|-----------|
| EMST + SpiroGym (NCT06942533) | Recruiting | Visual feedback-enhanced expiratory training |
| Standard EMST | Evidence-based | Progressive resistance breathing exercises |
| Lee Silverman Voice Treatment (LSVT) | Standard of Care | Voice and swallow rehabilitation |

Related Pages

• [Parkinson's Disease](/diseases/parkinsons-disease)](/proteins/parkin)
• [Autonomic Nervous System](/entities/autonomic-nervous-system)](/entities)
• [Alpha-Synuclein](/proteins/alpha-synuclein)](/proteins)
• [Digital Therapeutics](/digital-therapeutics)

Principal Investigator

Martin Srp, Ph.D.
Chief Physiotherapist
General University Hospital, Prague
Department of Neurology and Centre of Clinical Neuroscience
First Faculty of Medicine, Charles University

Contact: martin.srp@vfn.cz | +420224965513

External Links

• [ClinicalTrials.gov - NCT06942533](https://clinicaltrials.gov/study/NCT06942533)
• [General University Hospital Prague](https://www.vfn.cz/)

References

Pathway Diagram

The following diagram shows the key molecular relationships involving EMST with SpiroGym App for Parkinson's Disease (NCT06942533) discovered through SciDEX knowledge graph analysis: