Respiratory Muscle Strength Training in Presbyphonia

Study Overview
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Brief Summary
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Presbyphonia is an age-related voice disorder that affects more than 10 million people in the United States. Presbyphonia is characterized by vocal fold atrophy that impairs older individuals' ability to communicate, leading to social isolation and reduced quality of life. Outcomes from current treatment approaches are often suboptimal for patients with presbyphonia as they do not sufficiently challenge the respiratory system to induce meaningful change. It is highly likely that the addition of respiratory training would result in greatly improved outcomes, such as the ability to speak loud and long enough to have a normal conversation. The purpose of this study will be to examine the effect of adding inspiratory muscle strength training (IMST) or expiratory muscle strength training (EMST) to standard of care voice therapy on respiratory and voice outcomes in patients with an age-related voice disorder. Forty-eight participants diagnosed with presbyphonia will be blocked-randomized into three intervention groups, using a 3-parallel arm design: IMST and voice exercises, EMST and voice exercises, and voice exercises during all session. Study endpoints will be the change in voice and respiratory measures after four treatment sessions compared to baseline values. Response to treatment will be analyzed to determine if there are subgroups of high- or low-responders based on baseline voice and respiratory characteristics.

Official Title
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Respiratory Muscle Strength Training in Presbyphonia

Conditions
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Presbylarynx

Intervention / Treatment
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* Device: Inspiratory Muscle Strength Training (IMST)
* Device: Expiratory Muscle Strength Training (EMST)
* Behavioral: Voice Exercises


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: must receive a diagnosis of presbyphonia by a trained laryngologist. The diagnosis will be given following a visual examination if the observations are consistent with the characteristics of a presbylarynx, as judged by the laryngologist. must be 50 years old and older. Exclusion Criteria: has received voice therapy in the past year presents with a vocal fold pathology other than presbyphonia has a known neurologic or a progressive neuromuscular disease has a medical condition that could be aggravated by the experimental intervention, or any condition judged by the physician (Dr. Halstead) as being unsuitable for RMST. has dysarthria or a language disorder has a hearing loss that is not adequately managed has a cognitive disorder that might affect treatment compliance is unable to give informed consent

Ages Eligible for Study
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Minimum Age: 50 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Inspiratory Muscle Strength Training<br>The participants in the IMST arm will receive, in addition to standard of care voice therapy, inspiratory muscle strength training (IMST). The IMST intervention will consist of 5 sets of 5 breaths in the inspiratory threshold device every day during four weeks, with a loading dose set at 75% of the participants' maximal inspiratory pressure (MIP). MIP will be measured once a week during the weekly supervised session to adjust the inspiratory trainer. | Device: Inspiratory Muscle Strength Training (IMST)<br>* IMST will be conducted using an inspiratory pressure threshold trainer (Philips Respironics® Threshold IMT or POWERbreathe® Medic Plus), which consists of a mouthpiece with a spring-loaded valve. The valve blocks the airflow until the threshold pressure is achieved by breathing in forcefully into the device. This allows airflow as long as the sufficient pressure is maintained.<br>* Other names: POWERbreathe® Medic Plus;Behavioral: Voice Exercises<br>* Voice exercises will consist of the Vocal Function Exercises (VFE) protocol, developed by Stemple (2005). It contains 4 steps: (a) sustain the vowel /i/ on the musical note F for as long as possible. Repeat as judged by the SLP. (b) Glide from the lowest note to the highest note. Repeat as judged by the SLP. (c) Glide from the highest note to the lowest note. Repeat as judged by the SLP. (d) Sustain the notes C-D-E-F-G for as long as possible. Each note will be repeated until the participant finds the right placement (forward-focused voice), as judged by the SLP. Humming will be used to facilitate placement.<br>|
| Experimental: Expiratory Muscle Strength Training<br>The participants in the EMST arm will receive, in addition to standard of care voice therapy, expiratory muscle strength training (EMST). The EMST intervention will consist of 5 sets of 5 breaths in the expiratory threshold device every day during four weeks, with a loading dose set at 75% of the participants' maximal expiratory pressure (MEP). MEP will be measured once a week during the weekly supervised session to adjust the inspiratory trainer. | Device: Expiratory Muscle Strength Training (EMST)<br>* EMST will be conducted using an expiratory pressure threshold trainer (EMST150®), which consists of a mouthpiece with a spring-loaded valve. The valve blocks the airflow until the threshold pressure is achieved by breathing out forcefully into the device. This allows airflow as long as the sufficient pressure is maintained.<br>* Other names: EMST150®;Behavioral: Voice Exercises<br>* Voice exercises will consist of the Vocal Function Exercises (VFE) protocol, developed by Stemple (2005). It contains 4 steps: (a) sustain the vowel /i/ on the musical note F for as long as possible. Repeat as judged by the SLP. (b) Glide from the lowest note to the highest note. Repeat as judged by the SLP. (c) Glide from the highest note to the lowest note. Repeat as judged by the SLP. (d) Sustain the notes C-D-E-F-G for as long as possible. Each note will be repeated until the participant finds the right placement (forward-focused voice), as judged by the SLP. Humming will be used to facilitate placement.<br>|
| Active Comparator: Voice Exercises<br>The participants in the voice exercises group will receive standard of care voice therapy with a speech language pathologist, once a week during four weeks, plus daily practices. | Behavioral: Voice Exercises<br>* Voice exercises will consist of the Vocal Function Exercises (VFE) protocol, developed by Stemple (2005). It contains 4 steps: (a) sustain the vowel /i/ on the musical note F for as long as possible. Repeat as judged by the SLP. (b) Glide from the lowest note to the highest note. Repeat as judged by the SLP. (c) Glide from the highest note to the lowest note. Repeat as judged by the SLP. (d) Sustain the notes C-D-E-F-G for as long as possible. Each note will be repeated until the participant finds the right placement (forward-focused voice), as judged by the SLP. Humming will be used to facilitate placement.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Post-Treatment Mean in Voice Handicap Index Score | Voice Handicap Index-10 (ordinal scale that measures the degree of handicap a person experiences because of their voice disorder. Minimum score 0, maximal score 40. A lower score is better ) | up to 5 weeks after baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Post-treatment Mean in (Habitual) Sound Pressure Level | Acoustic measure of loudness, in Decibels | up to 5 weeks after baseline | 
| Post-treatment Mean in Baseline Smoothed Cepstral Peak Prominence (CPPS) (During Reading) | Acoustic measure of voice quality, in Decibels | up to 5 weeks after baseline | 
| Post-treatment Mean in Baseline Noise-to-harmonic Ratio (NHR) | Acoustic measure of voice quality, expressed as a ratio of noise to harmonics in the signal. | up to 5 weeks after baseline | 
| Post-Treatment Mean in Baseline Amplitude Perturbation Quotient (APQ) | Acoustic measure of voice quality, expressed as a percentage | up to 5 weeks after baseline | 
| Post-treatment Mean in Overall Severity of Voice Quality | This is a auditory-perceptual measure rated on the standardized form: Consensus Auditory-Perceptual Evaluation of Voice (a 100-mm visual analogue scale where 0 represents a normal voice and 100 represents an extremely disrupted voice quality. A lower score is better). | up to 5 weeks after baseline | 
| Post-treatment Mean in Baseline Bowing Index | Measure of vocal fold atrophy, calculated as the length of the membranous vocal fold/distance from the edge x100. The index was calculated based on still images from the larynx obtained from videostroboscopy. A smaller bowing index is indicative of less atrophy, and is therefore a better outcome. A greater bowing index is indicative of more atrophy and represent a worse outcome. | up to 5 weeks after baseline | 
| Post-treatment Mean in Communicative Participation Item Bank (CPIB) Score | Ordinal scale measuring the impact of the communication disorder on various situations. A higher score is indicative of a more functional communication (the minimum score is 0 and the maximum score is 30). | up to 5 weeks after baseline | 
| Post-treatment Mean in Glottal Function Index (GFI) Score | Glottal Function Index (ordinal scale that measures the presence and degree of symptoms of glottal dysfunction experienced by a patient. Minimum score is 0, maximum score is 20. A lower score is better). | up to 5 weeks after baseline | 
| Post-treatment Mean in Average Glottal Airflow | Aerodynamic measure of voice expressed in Liters/second | up to 5 weeks after baseline | 
| Post-treatment Mean in Average Subglottal Pressure | Aerodynamic measure of voice expressed in cmH20 | up to 5 weeks after baseline | 
| Post-treatment Mean in Aerodynamic Resistance | Aerodynamic measure (subglottal pressure divided by mean flow rate), expressed as cmH20/liters/second | up to 5 weeks after baseline | 
| Post-treatment Mean in Maximum Expiratory Pressure (MEP) | Indirect measure of respiratory (expiratory) muscle strength, expressed in cmH20 | up to 5 weeks after baseline | 
| Post-treatment Mean in Maximum Inspiratory Pressure (MIP) | Indirect measure of respiratory muscle strength, expressed in cmH20 | up to 5 weeks after baseline | 
| Post-treatment Mean in Forced Vital Capacity (FVC) | Measure of pulmonary function, expressed as a percent predicted value | up to 5 weeks after baseline | 
| Post-treatment Mean in Forced Expiratory Volume in 1 Second (FEV1) | Measure of pulmonary function expressed as percent predicted value | up to 5 weeks after baseline | 
| Post-Treatment Mean for FEV1/FVC | Pulmonary function measure expressed as percent predicted value (ratio between forced expiratory volume in one second and forced vital capacity) | up to 5 weeks after baseline |