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Respiratory Muscle Training (RMT) in ALS

Moderate Intensity Respiratory Muscle Training (RMT) in ALS

Status
Completed
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04224961
Enrollment
9
Registered
2020-01-13
Start date
2020-01-14
Completion date
2022-11-29
Last updated
2026-01-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

ALS

Brief summary

Twelve adults with ALS will participate in a study involving four 3-week cycles of progressive respiratory muscle training (RMT). The investigators will measure maximum inspiratory pressure (MIP) and maximum expiratory pressure (MEP) weekly. The investigators will obtain the majority of measurements of MIP and MEP during web-based telehealth visits. Participants will be stratified into 2 groups based on baseline inspiratory muscle strength as determined by maximum inspiratory pressure (MIP): six participants with minimal to no respiratory weakness (i.e., MIP ≥ 70% predicted) and six participants with mild to moderate inspiratory weakness (i.e., MIP 40-70% predicted).

Detailed description

Twelve adults will participate in a single- subject A1-B-A2 study involving 4 visits to Duke over 24 weeks. The 6 week delayed start period (A1) will establish baseline status prior to initiation of RMT (B) and the follow-up period (A2) will determine detraining effects over 6 weeks of RMT withdrawal. Participants will complete four 3-week cycles of progressive RMT during the B phase. The investigators will measure MIP and MEP weekly. To reduce participant burden and enhance our ability to obtain repeated measures, the investigators will obtain 21 of 25 measurements of MIP and MEP during web-based telehealth visits. Participants will complete a full assessment during the first study visit (M1) and receive training/instruction for obtaining MIP and MEP measurements at home with a portable, battery-powered digital pressure gauge manometer (MicroRPM Pressure Meter; Micro Direct). They will return to Duke for the pretest visit (M7), at which time a full assessment will be completed and RMT will commence. During the B phase, participants will complete 12-weeks of moderate intensity RMT, divided into four 3-week cycles, and participate in weekly web-based RMT therapy visits (M8-M18). Post-test assessment (M19) will occur immediately following completion of the 12-week RMT regimen. The investigators will measure MIP and MEP during RMT withdrawal via web-based telehealth visits (M20-24). Following the fourth and final on-site full assessment visit (M25), participants will return all equipment and will be offered the opportunity to initiate a clinical RMT regimen and receive follow-up care by Speech Pathology during future ALS Clinic visits. Participants will be stratified into 2 groups based on baseline inspiratory muscle strength as determined by maximum inspiratory pressure (MIP): six participants with minimal to no respiratory weakness (i.e., MIP ≥ 70% predicted) and six participants with mild to moderate inspiratory weakness (i.e., MIP 40-70% predicted). The primary outcomes are MIP and MEP. Secondary outcomes include peak cough flow (PCF) and sniff nasal inspiratory pressure (SNIP). Exploratory outcomes include the Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS), Eating Assessment Tool - 10 Item (EAT-10), 36-Item Short Form Survey (SF36), World Health Organization Quality of Life-BREF (WHOQOL-BREF), and Communicative Effectiveness Survey-Revised (CES-R). Clinical spirometry data will be extracted from the participant's electronic medical record if available from a coinciding ALS Clinic visit that occurs +/- 5 days from the assessment visit.

Interventions

DEVICERespiratory Muscle Training

Two commercially available pressure-threshold RMT devices that utilize a spring-loaded flange to provide resistance against inspiration and expiration independent of respiratory flow rate will be used to provide the necessary range of resistance. Each participant will use two RMT devices, one for IMT and one for EMT.

Sponsors

Duke University
Lead SponsorOTHER

Study design

Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
SUPPORTIVE_CARE
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Age ≥ 18 years * Confirmed diagnosis of ALS * Ability to follow directions for study participation * Ability to successfully and independently complete RMT repetitions at a minimum pressure-threshold target equal to 30% of MIP or MEP * Ability to complete telehealth visits using a smartphone or computer with video capabilities * Ability to complete a home-RMT regimen

Exclusion criteria

* MIP \< 40 cmH20 * Presence of a tracheostomy * Use of non-invasive or invasive ventilation when awake * Participant or caregiver(s) inability to manipulate respiratory pressure meter, the RMT device, or calibration equipment for home training * Inability to complete RMT repetitions successfully * Concomitant neurologic or neurodegenerative conditions (e.g. stroke, dementia) or other serious conditions that would prevent meaningful study participation as determined at the discretion of the principal investigator * Inability to give legally effective consent * Inability to read and understand English

Design outcomes

Primary

MeasureTime frameDescription
Number of Participants With Safe, Well-tolerated Moderate Intensity Respiratory Muscle Training (RMT) as Measured by Rating of Perceived Exertion (RPE)12 weeksSafe, well-tolerated moderate intensity Respiratory Muscle Training (RMT) is in part defined as an RPE between 4-5 and \<6. The RPE is a way of measuring physical activity intensity level. Perceived exertion is how hard the participant feels like their body is working. 0 = rest, 1 = very easy, 2 = easy, 3 = moderate, 4 = somewhat hard, 5 = hard, 6 = harder, 7 = very hard, 8/9 = extremely hard, 10 = maximal.
Number of Participants With Safe, Well-tolerated Moderate Intensity Respiratory Muscle Training (RMT) as Measured by Pain Score12 weeksSafe, well-tolerated moderate intensity Respiratory Muscle Training (RMT) is in part defined as a pain rating of \<4 on a standard 0-10 scale, where 0 = no pain and 10 = the worst pain possible.
Number of Participants Able to Complete Respiratory Muscle Training (RMT)12 weeksFeasibility will be determined by the number of participants able to complete the Respiratory Muscle Training
Magnitude of Change in Maximum Inspiratory Pressure From Pre-test to Post-test as Determined by Cohen's Measure of Effect Sizefrom pre-test (week 7) to post-test (week 18)Magnitude of change for our primary outcome measures will be determined using Cohen's measure of effect size (d) as defined by the first equation for single-subject d provided by Busk and Serlin (1992). Simply stated, d is obtained by subtracting the mean of the first assessment from the mean of the second assessment, divided by the standard deviation of the first assessment. Effect size calculations will be determined to compare results from pre-test (M7) to post-test (M18). The investigators will use conservative interpretation guidelines for effect size calculations in which d \< 0.6 is negligible, d ≥ 0.6 modest, d ≥ 1.0 large, and d ≥ 2.0 very large.
Magnitude of Change in Maximum Expiratory Pressure From Baseline to Withdrawal as Determined by Cohen's Measure of Effect Sizefrom baseline to withdrawal (up to week 24)Magnitude of change for our primary outcome measures will be determined using Cohen's measure of effect size (d) as defined by the first equation for single-subject d provided by Busk and Serlin (1992). Simply stated, d is obtained by subtracting the mean of the first assessment from the mean of the second assessment, divided by the standard deviation of the first assessment. Effect size calculations will be determined to compare results from baseline (M0-M5) to withdrawal (M19-M24). The investigators will use conservative interpretation guidelines for effect size calculations in which d \< 0.6 is negligible, d ≥ 0.6 modest, d ≥ 1.0 large, and d ≥ 2.0 very large.

Secondary

MeasureTime frameDescription
Change in Peak Cough Flow in L/MinBaseline, 7 weeks, 18 weeks, 24 weeksEffective peak cough flow in healthy subjects exceeds values of 360 to 400 L/min. PCF is measured at baseline, visit 7, visit 18 and visit 24. The overall change from baseline to visit 24 will be measured.
Change in Sniff Nasal Inspiratory PressureBaseline, 7 weeks, 18 weeks, 24 weeksThe sniff nasal inspiratory pressure (SNIP) consists in the measurement of pressure through an occluded nostril during sniffs performed through the contralateral nostril. SNIP is measured through a plug occluding one nostril during sniffs through the contralateral nostril. A plateau in pressure is reached after 5-10 sniffs in most individuals 1. For SNIP measurement, 10 sniffs are usually performed. The SNIP is measured at baseline, visit 7, visit 18 and visit 24. The overall change from baseline to visit 24 will be measured.

Countries

United States

Contacts

PRINCIPAL_INVESTIGATORHarrison Jones, PhD

Duke University

Baseline characteristics

Characteristic
Age, Continuous73.0 years
STANDARD_DEVIATION 0
Ethnicity (NIH/OMB)
Hispanic or Latino
0 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
9 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
Race (NIH/OMB)
Asian
0 Participants
Race (NIH/OMB)
Black or African American
0 Participants
Race (NIH/OMB)
More than one race
0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
White
9 Participants
Region of Enrollment
United States
9 Participants
Sex: Female, Male
Female
3 Participants
Sex: Female, Male
Male
5 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 80 / 1
other
Total, other adverse events
5 / 81 / 1
serious
Total, serious adverse events
0 / 81 / 1

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026