Chronic Obstructive Pulmonary Disease
Conditions
Keywords
COPD, Alveolar-capillary membrane integrity, Lung tissue mass, Cardiac Output, DLCO/DLNO
Brief summary
It is unknown whether individuals with COPD exhibit abnormal alveolar-capillary breaching during exercise, and whether this contributes to exertional dyspnoea. The aim of this study is to investigate whether individuals with COPD exhibit an abnormal increase in alveolar-capillary breaching during exertion, as indicated by an increase alveolar-capillary permeability with a concomitantly exacerbated increase in lung tissue mass.
Detailed description
It is unknown whether individuals with COPD exhibit abnormal alveolar-capillary breaching during exercise, and whether this contributes to exertional dyspnoea. The aim of this study is to investigate whether individuals with COPD exhibit an abnormal increase in alveolar-capillary breaching during exertion, as indicated by an increase alveolar-capillary permeability with a concomitantly exacerbated increase in lung tissue mass. The study participants include a control group and a group with COPD (GOLD I-III). Participants are undergoing three study days: (1) Measurement of maximal aerobic capacity and lung function test, (2) lung tissue mass and alveolar-capillary permeability is measured at rest and again 2 hours later, immediately after the participant has exercised on a bicycle ergometer and (3) supine cardiac output and pulmonary capillary blood volume will be measured at rest and immediately after exercise.
Interventions
OTHERAcute exercise bout on visit 2 and 3
1\) a 5-minute warm-up, 2) 4 minutes at 60% of the maximal workload (determined on Study Day 1), 3) 2 minutes active break at 15 watt, 4) 4 minutes at maximal workload.
Sponsors
Rigshospitalet, Denmark
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
45 Years to 80 Years
Healthy volunteers
Yes
Inclusion criteria
- individuals with COPD * Men and women * 45-80 years old * COPD (GOLD stage I to III) * Resting arterial oxygenation \> 90% Inclusion criteria - healthy controls * Men and women * 45-80 years old * Non-smokers * Normal lung function * Same sex, age (± 3 years) as the COPD group
Exclusion criteria
- individuals with COPD * Symptoms of ischemic heart disease * Known heart failure * Symptoms of illness, including fever, within 2 weeks prior to the study * Pregnancy * • Known renal or liver diseaseActive smoking (within 3 weeks)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Rest-to-exercise pulmonary DTPA clearance change after exercise in COPD vs. controls | Measured at study day 2 | The physiological change from rest to exercise in DTPA clearance |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Pulmonary DTPA clearance at rest in COPD vs. controls | Measured at study day 2 | Pulmonary DTPA clearance measured by pulmonary DTPA clearance at rest |
| Pulmonary DTPA clearance after exercise in COPD vs. controls | Measured at study day 2 | Pulmonary DTPA clearance measured by pulmonary DTPA clearance after exercise |
| Rest-to-exercise change in lung tissue mass in COPD vs. controls | Measured at study day 2 | The physiological change from rest to exercise in lung tissue mass measured by low-dose CT-scan |
Other
| Measure | Time frame | Description |
|---|---|---|
| Rest-to-exercise pulmonary DTPA clearance and lung tissue mass change according to GOLD | Measured at study day 2 | The physiological change from rest to exercise in lung tissue mass measured by low-dose CT-scan and the physiological change from rest to exercise in DTPA clearance according to different GOLD stages |
| Supine pulmonary capillary blood volume after exercise in COPD vs. controls | Measured at study day 3 | Pulmonary capillary blood volume (VC) after exercise obtained by combined DLCO/NO technique with 5-sec breath-hold |
| Supine cardiac output after exercise in COPD vs. controls | Measured at study day 3 | Cardiac output measured after exercise by a Finometer device |
| Supine pulmonary capillary blood volume at rest in COPD vs. controls | Measured at study day 3 | VC at rest obtained by combined DLCO/NO technique with 5-sec breath-hold |
| Supine alveolar-capillary membrane diffusing capacity (DM) after exercise in COPD vs. controls | Measured at study day 3 | Membrane diffusion capacity (DM) after exercise obtained by combined DLCO/NO technique with 5-sec breath-hold |
| Supine pulmonary diffusing capacity to nitric oxide (DLNO) after exercise in COPD vs. controls | Measured at study day 3 | DLNO measured after exercise by combined DLCO/NO technique with 5-sec breath-hold |
| Supine haemoglobin-corrected pulmonary diffusing capacity to carbon monoxide (DLCOc) after exercise in COPD vs. controls | Measured at study day 3 | DLCOc measured after exercise by combined DLCO/NO technique with 5-sec breath-hold |
| Supine haemoglobin-corrected pulmonary diffusing capacity to carbon monoxide (DLCOc) at rest in COPD vs. controls | Measured at study day 3 | DLCOc measured at rest by combined DLCO/NO technique with 5-sec breath-hold |
| Supine alveolar-capillary membrane diffusing capacity (DM) at rest in COPD vs. controls | Measured at study day 3 | DM after exercise obtained by combined DLCO/NO technique with 5-sec breath-hold |
| Supine cardiac output at rest in COPD vs. controls | Measured at study day 3 | Cardiac output measured at rest by a Finometer device |
| Supine pulmonary diffusing capacity to nitric oxide (DLNO) at rest in COPD vs. controls | Measured at study day 3 | DLNO measured at rest by combined DLCO/NO technique with 5-sec breath-hold |
| Lung tissue mass at rest in COPD vs. controls | Measured at study day 2 | Lung tissue mass measured at rest by low-dose CT-scan |
| Lung tissue mass after exercise in COPD vs. controls | Measured at study day 2 | Lung tissue mass measured at exercise by low-dose CT-scan |
Countries
Denmark
Outcome results
None listed