Trial Outcomes & Findings for Uphill Walking as Exercise for COPD Patients (NCT NCT04026529)

NCT ID: NCT04026529

Last Updated: 2024-08-30

Results Overview

Perceived dyspnea: Breathlessness will be measured based on a 0 to 10-point Borg scale at the end of the treadmill trials. 0 on scale is no breathlessness and 10 is maximal breathlessness

• Recruitment status: COMPLETED
• Study phase: NA
• Target enrollment: 8 participants
• Primary outcome timeframe: Visits were assessed at pre-specified randomized slope/speed treadmill intervals, with each visit scheduled to occur within one week of the previous visit, all taking place within a 6-week period following enrollment
• Results posted on: 2024-08-30

Participant Flow

Participant milestones

Measure	Walking at Incline or Speed Subjects will walk on treadmill at slope and speed to equal 60% of their peak work rate as determined on baseline cardiopulmonary exercise test. Walking on incline or walking at increasing speed: Subjects will be prepared for data collection by wearing a form-fitting suit (i.e., wrestling singlet) and obtaining height and body weight. Retro-reflective markers will be placed bilaterally on anatomical locations of the feet, legs, and hips. Subjects will be outfitted with the portable metabolic cart and oximeter as in the previous visit. One of two treadmill trials will be performed: 1) at the speed and 2) at the slope +speed determined in the previous visit. Trial order will be randomized among subjects and across visits 3 \& 4. For each trial, subjects will be asked to walk on a treadmill for up to 6 minutes. Speed or slope will be increased every 30 seconds and they will be asked to walk for one minute at that speed or slope.
Overall Study STARTED	8
Overall Study COMPLETED	8
Overall Study NOT COMPLETED	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Uphill Walking as Exercise for COPD Patients

Baseline characteristics by cohort

Measure	Walking at Incline or Speed n=8 Participants Subjects will walk on treadmill at slope and speed to equal 60% of their peak work rate as determined on baseline cardiopulmonary exercise test. Walking on incline or walking at increasing speed: Subjects will be prepared for data collection by wearing a form-fitting suit (i.e., wrestling singlet) and obtaining height and body weight. Retro-reflective markers will be placed bilaterally on anatomical locations of the feet, legs, and hips. Subjects will be outfitted with the portable metabolic cart and oximeter as in the previous visit. One of two treadmill trials will be performed: 1) at the speed and 2) at the slope +speed determined in the previous visit. Trial order will be randomized among subjects and across visits 3 \& 4. For each trial, subjects will be asked to walk on a treadmill for up to 6 minutes. Speed or slope will be increased every 30 seconds and they will be asked to walk for one minute at that speed or slope.
Age, Categorical <=18 years	0 Participants n=5 Participants
Age, Categorical Between 18 and 65 years	1 Participants n=5 Participants
Age, Categorical >=65 years	7 Participants n=5 Participants
Age, Continuous	67.25 years STANDARD_DEVIATION 3.69 • n=5 Participants
Sex: Female, Male Female	3 Participants n=5 Participants
Sex: Female, Male Male	5 Participants n=5 Participants
Race/Ethnicity, Customized White	8 Participants n=5 Participants
Region of Enrollment United States	8 Participants n=5 Participants
Participants have COPD.	8 Participants n=5 Participants

PRIMARY outcome

Timeframe: Visits were assessed at pre-specified randomized slope/speed treadmill intervals, with each visit scheduled to occur within one week of the previous visit, all taking place within a 6-week period following enrollment

Perceived dyspnea: Breathlessness will be measured based on a 0 to 10-point Borg scale at the end of the treadmill trials. 0 on scale is no breathlessness and 10 is maximal breathlessness

Outcome measures

Measure	Walking at Incline or Speed n=8 Participants Subjects will walk on treadmill at slope and speed to equal 60% of their peak work rate as determined on baseline cardiopulmonary exercise test. Walking on incline or walking at increasing speed: Subjects will be prepared for data collection by wearing a form-fitting suit (i.e., wrestling singlet) and obtaining height and body weight. Retro-reflective markers will be placed bilaterally on anatomical locations of the feet, legs, and hips. Subjects will be outfitted with the portable metabolic cart and oximeter as in the previous visit. One of two treadmill trials will be performed: 1) at the speed and 2) at the slope +speed determined in the previous visit. Trial order will be randomized among subjects and across visits 3 \& 4. For each trial, subjects will be asked to walk on a treadmill for up to 6 minutes. Speed or slope will be increased every 30 seconds and they will be asked to walk for one minute at that speed or slope.
Dyspnea slope visit, randomized either 3 or 4	9.62 score on a scale Standard Deviation 2.55
Dyspnea speed visit, randomized either 3 or 4	9.12 score on a scale Standard Deviation 3.04

OTHER_PRE_SPECIFIED outcome

Timeframe: Visits were assessed at pre-specified randomized slope/speed treadmill intervals, with each visit scheduled to occur within one week of the previous visit, all taking place within a 6-week period following enrollment

Dynamic hyperinflation will be assessed by inspiratory capacity through pre- and post-walking trial resting spirometry. Dynamic hyperinflation will be considered to be present when inspiratory capacity values decrease after walking trials when compared to resting values.

Outcome measures

Measure	Walking at Incline or Speed n=8 Participants Subjects will walk on treadmill at slope and speed to equal 60% of their peak work rate as determined on baseline cardiopulmonary exercise test. Walking on incline or walking at increasing speed: Subjects will be prepared for data collection by wearing a form-fitting suit (i.e., wrestling singlet) and obtaining height and body weight. Retro-reflective markers will be placed bilaterally on anatomical locations of the feet, legs, and hips. Subjects will be outfitted with the portable metabolic cart and oximeter as in the previous visit. One of two treadmill trials will be performed: 1) at the speed and 2) at the slope +speed determined in the previous visit. Trial order will be randomized among subjects and across visits 3 \& 4. For each trial, subjects will be asked to walk on a treadmill for up to 6 minutes. Speed or slope will be increased every 30 seconds and they will be asked to walk for one minute at that speed or slope.
Dynamic Hyperinflation slope visit randomized either 3rd or 4th visit	0.21 Percentage of tidal volume/lung capacity Standard Deviation 0.61
Dynamic Hyperinflation speed visit randomized either 3rd or 4th visit	-0.11 Percentage of tidal volume/lung capacity Standard Deviation 0.42

OTHER_PRE_SPECIFIED outcome

Timeframe: Visits were assessed at pre-specified randomized slope/speed treadmill intervals, with each visit scheduled to occur within one week of the previous visit, all taking place within a 6-week period following enrollment

Respiratory rate will be analyzed using motion capture markers on the chest. With custom computer code, the markers will be identified to model a sphere. The volume of the sphere will be recorded over time. As the volume increases and decreases, respiratory flow will be identified, and respiratory rate can be calculated.

Outcome measures

Measure	Walking at Incline or Speed n=8 Participants Subjects will walk on treadmill at slope and speed to equal 60% of their peak work rate as determined on baseline cardiopulmonary exercise test. Walking on incline or walking at increasing speed: Subjects will be prepared for data collection by wearing a form-fitting suit (i.e., wrestling singlet) and obtaining height and body weight. Retro-reflective markers will be placed bilaterally on anatomical locations of the feet, legs, and hips. Subjects will be outfitted with the portable metabolic cart and oximeter as in the previous visit. One of two treadmill trials will be performed: 1) at the speed and 2) at the slope +speed determined in the previous visit. Trial order will be randomized among subjects and across visits 3 \& 4. For each trial, subjects will be asked to walk on a treadmill for up to 6 minutes. Speed or slope will be increased every 30 seconds and they will be asked to walk for one minute at that speed or slope.
Respiratory Rate speed visit, slope visit, randomized either 3rd or 4th visit	26.5 breath per minute Standard Deviation 6.34
Respiratory Rate slope visit, randomized either 3rd or 4th visit	27.49 breath per minute Standard Deviation 6.79

OTHER_PRE_SPECIFIED outcome

Timeframe: Visits were assessed at pre-specified randomized slope/speed treadmill intervals, with each visit scheduled to occur within one week of the previous visit, all taking place within a 6-week period following enrollment

The laboratory is equipped with a 17-camera, digital motion capture system (Motion Analysis Corp., Santa Rosa, CA; 120Hz) to allow for collection of three-dimensional marker positions in real time.

The breathing cycle will be determined based on the movement of markers placed on the chest, while the gait cycles will be identified using locomotor data derived from heel markers, focusing on heel contact events.

Coupling is often quantified as frequency coupling. Frequency coupling refers to how many heel strikes occur within a single cycle of respiration (one inhalation to the next).

Outcome measures

Measure	Walking at Incline or Speed n=8 Participants Subjects will walk on treadmill at slope and speed to equal 60% of their peak work rate as determined on baseline cardiopulmonary exercise test. Walking on incline or walking at increasing speed: Subjects will be prepared for data collection by wearing a form-fitting suit (i.e., wrestling singlet) and obtaining height and body weight. Retro-reflective markers will be placed bilaterally on anatomical locations of the feet, legs, and hips. Subjects will be outfitted with the portable metabolic cart and oximeter as in the previous visit. One of two treadmill trials will be performed: 1) at the speed and 2) at the slope +speed determined in the previous visit. Trial order will be randomized among subjects and across visits 3 \& 4. For each trial, subjects will be asked to walk on a treadmill for up to 6 minutes. Speed or slope will be increased every 30 seconds and they will be asked to walk for one minute at that speed or slope.
Percentage of Time in Which the Most Common Ratio of Coupling Was Detected slope visit randomized either 3rd or 4th visit	51.08 percentage of time Standard Deviation 24.67
Percentage of Time in Which the Most Common Ratio of Coupling Was Detected speed visit randomized either 3rd or 4th visit	74.13 percentage of time Standard Deviation 14.43

OTHER_PRE_SPECIFIED outcome

Timeframe: Visits were assessed at pre-specified randomized slope/speed treadmill intervals, with each visit scheduled to occur within one week of the previous visit, all taking place within a 6-week period following enrollment

Heart rate and pulmonary gas exchange analysis will be recorded on a breath-by-breath basis. This will provide an accurate measure of pulmonary gas exchange, including oxygen uptake, i.e. VO2, . Steady-state VO2 while walking will be averaged and normalized to standing metabolic rate.

Outcome measures

Measure	Walking at Incline or Speed n=8 Participants Subjects will walk on treadmill at slope and speed to equal 60% of their peak work rate as determined on baseline cardiopulmonary exercise test. Walking on incline or walking at increasing speed: Subjects will be prepared for data collection by wearing a form-fitting suit (i.e., wrestling singlet) and obtaining height and body weight. Retro-reflective markers will be placed bilaterally on anatomical locations of the feet, legs, and hips. Subjects will be outfitted with the portable metabolic cart and oximeter as in the previous visit. One of two treadmill trials will be performed: 1) at the speed and 2) at the slope +speed determined in the previous visit. Trial order will be randomized among subjects and across visits 3 \& 4. For each trial, subjects will be asked to walk on a treadmill for up to 6 minutes. Speed or slope will be increased every 30 seconds and they will be asked to walk for one minute at that speed or slope.
Oxygen Uptake speed visit randomized either 3rd or 4th visit	15.28 ml/kg/min Standard Deviation 4.45
Oxygen Uptake slope visit randomized either 3rd or 4th visit	14.16 ml/kg/min Standard Deviation 3.50

OTHER_PRE_SPECIFIED outcome

Timeframe: Visits were assessed at pre-specified randomized slope/speed treadmill intervals, with each visit scheduled to occur within one week of the previous visit, all taking place within a 6-week period following enrollment

Dead space: Tidal volume and expired carbon dioxide will be measured using the same equipment as oxygen uptake above. Partial pressure of arterial carbon dioxide will be measured using a transcutaneous sensor.

Outcome measures

Measure	Walking at Incline or Speed n=8 Participants Subjects will walk on treadmill at slope and speed to equal 60% of their peak work rate as determined on baseline cardiopulmonary exercise test. Walking on incline or walking at increasing speed: Subjects will be prepared for data collection by wearing a form-fitting suit (i.e., wrestling singlet) and obtaining height and body weight. Retro-reflective markers will be placed bilaterally on anatomical locations of the feet, legs, and hips. Subjects will be outfitted with the portable metabolic cart and oximeter as in the previous visit. One of two treadmill trials will be performed: 1) at the speed and 2) at the slope +speed determined in the previous visit. Trial order will be randomized among subjects and across visits 3 \& 4. For each trial, subjects will be asked to walk on a treadmill for up to 6 minutes. Speed or slope will be increased every 30 seconds and they will be asked to walk for one minute at that speed or slope.
Lung Dead Space slope visit randomized either 3rd or 4th visit	0.48 ml Standard Deviation 0.19
Lung Dead Space speed visit randomized either 3rd or 4th visit	0.51 ml Standard Deviation 0.18

Adverse Events

Walking at Incline or Speed

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Dr. Debra Romberger

Omaha VA Medical Center

Phone: 4025597539

Email: debra.romberger@va.gov

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place