Patients With Pulmonary Hypertension or Interstitial Lung Disease at Altitude - Effect of Oxygen on Exercise Performance

Study Overview
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Brief Summary
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The purpose of this study is to investigate the effect of travelling to moderate altitude and of nocturnal oxygen therapy during a stay at moderate altitude on exercise performance of patients with pulmonary hypertension or with interstitial lung disease.

Detailed Description
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Patients with pulmonary hypertension or with interstitial lung disease living below 800 m will be invited to participate in a randomized, cross-over field trial evaluating the hypotheses that: a), exercise capacity during a 2 day sojourn at moderate altitude is reduced in comparison to low altitude; b), exercise capacity during a 2 day sojourn at moderate altitude is improved by nocturnal oxygen therapy compared to room air (sham oxygen) administered during nights at altitude. Outcomes will be assessed at low altitude (Zurich, 490 m, baseline), and during 2 study periods of 2 days each spent at moderate altitude (St. Moritz Salastrains, 2048 m), separated by a wash-out period of at least 2 weeks spent at low altitude (<800 m). The order of stays at the different altitudes and of the treatments will be randomized.

Official Title
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Patients With Pulmonary Hypertension or Interstitial Lung Disease Travelling to Altitude - Effect of Nocturnal Oxygen Therapy on Exercise Performance

Conditions
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Precapillary Pulmonary Hypertension, Interstitial Lung Disease

Intervention / Treatment
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* Behavioral: Moderate altitude sojourn
* Behavioral: Low altitude sojourn
* Drug: Oxygen
* Drug: Sham oxygen (room air)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Precapillary pulmonary hypertension, or interstitial lung disease. New York Heart Association class 2-3. Residence at low altitude (<800m). Exclusion Criteria: Unstable or exacerbated condition Very severe pulmonary hypertension or interstitial lung disease, New York Heart Association class 4 Requirement for oxygen therapy at low altitude residence Hypoventilation More than mild or unstable cardiovascular disease Use of drugs that affect respiratory center drive Internal, neurologic or psychiatric disease that interfere with protocol compliance including current heavy smoking (>20 cigarettes per day), inability to perform 6 min walk test. Previous intolerance to moderate altitude (<2600m). Exposure to altitudes >1500m for >2 days within the last 4 weeks before the study. Pregnant or nursing patients

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 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: Crossover Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Moderate altitude sojourn<br>Sojourn at moderate altitude (2048 m) | Behavioral: Moderate altitude sojourn<br>* Participants will travel from Zurich (490 m) to St. Moritz Salastrains (2048 m) and stay there for 2 days<br>* Other names: Moderate altitude sojourn at 2048 m for 2 days;Behavioral: Low altitude sojourn<br>* Low altitude baseline evaluations will be performed during a stay at Zurich (490)<br>* Other names: Low altitude sojourn at 490 m (Zurich) for 1.5 days;Drug: Oxygen<br>* Oxygen administration via a nasal cannula at a rate of 3 L/min during nights spent at 2048 m<br>* Other names: Nocturnal nasal oxygen administration during stay at 2048 m;Drug: Sham oxygen (room air)<br>* Sham oxygen (room air) administration via a nasal cannula at a rate of 3 L/min during nights at 490 m and 2048 m<br>* Other names: Nocturnal nasal room air administration;|
| Experimental: Low altitude sojourn<br>Sojourn at low altitude (490 m, baseline) | Behavioral: Moderate altitude sojourn<br>* Participants will travel from Zurich (490 m) to St. Moritz Salastrains (2048 m) and stay there for 2 days<br>* Other names: Moderate altitude sojourn at 2048 m for 2 days;Behavioral: Low altitude sojourn<br>* Low altitude baseline evaluations will be performed during a stay at Zurich (490)<br>* Other names: Low altitude sojourn at 490 m (Zurich) for 1.5 days;Drug: Oxygen<br>* Oxygen administration via a nasal cannula at a rate of 3 L/min during nights spent at 2048 m<br>* Other names: Nocturnal nasal oxygen administration during stay at 2048 m;Drug: Sham oxygen (room air)<br>* Sham oxygen (room air) administration via a nasal cannula at a rate of 3 L/min during nights at 490 m and 2048 m<br>* Other names: Nocturnal nasal room air administration;|
| Active Comparator: Oxygen<br>Oxygen administration via a nasal cannula at a rate of 3 L/min during nights spent at 2048 m | Behavioral: Moderate altitude sojourn<br>* Participants will travel from Zurich (490 m) to St. Moritz Salastrains (2048 m) and stay there for 2 days<br>* Other names: Moderate altitude sojourn at 2048 m for 2 days;Behavioral: Low altitude sojourn<br>* Low altitude baseline evaluations will be performed during a stay at Zurich (490)<br>* Other names: Low altitude sojourn at 490 m (Zurich) for 1.5 days;Drug: Oxygen<br>* Oxygen administration via a nasal cannula at a rate of 3 L/min during nights spent at 2048 m<br>* Other names: Nocturnal nasal oxygen administration during stay at 2048 m;Drug: Sham oxygen (room air)<br>* Sham oxygen (room air) administration via a nasal cannula at a rate of 3 L/min during nights at 490 m and 2048 m<br>* Other names: Nocturnal nasal room air administration;|
| Placebo Comparator: Sham oxygen (room air)<br>Sham oxygen (room air) administration via a nasal cannula at a rate of 3 L/min during nights | Behavioral: Moderate altitude sojourn<br>* Participants will travel from Zurich (490 m) to St. Moritz Salastrains (2048 m) and stay there for 2 days<br>* Other names: Moderate altitude sojourn at 2048 m for 2 days;Behavioral: Low altitude sojourn<br>* Low altitude baseline evaluations will be performed during a stay at Zurich (490)<br>* Other names: Low altitude sojourn at 490 m (Zurich) for 1.5 days;Drug: Oxygen<br>* Oxygen administration via a nasal cannula at a rate of 3 L/min during nights spent at 2048 m<br>* Other names: Nocturnal nasal oxygen administration during stay at 2048 m;Drug: Sham oxygen (room air)<br>* Sham oxygen (room air) administration via a nasal cannula at a rate of 3 L/min during nights at 490 m and 2048 m<br>* Other names: Nocturnal nasal room air administration;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 6 min walk distance | Difference in the distance walked in 6 min between measurements at 2048 m (altitude) and 490 m (baseline); and between the oxygen and sham oxygen treatment periods at 2028 m. | Day 2 at 2048 m | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 6 min walk distance | Difference in the distance walked in 6 min between measurements at 2048 m (altitude) and 490 m (baseline); and between the oxygen and sham oxygen treatment periods at 2028 m. | day 3 at 2048 m | 
| Arterial blood gas analysis | Change in arterial oxygen partial pressure, carbon dioxide partial pressure, and pH between measurements at 2048 m (altitude) and 490 m (baseline); and between the oxygen and sham oxygen treatment periods at 2028 m. | Day 2 at 2048 m | 
| Spirometry | Difference in spirometry between measurements at 2048 m (altitude) and 490 m (baseline); and between the oxygen and sham oxygen treatment periods at 2028 m. | Day 2 at 2048 m | 
| Perceived exertion | Difference in the perceived exertion rated with the BORG CR10 scale at the end of the 6 min walk between measurements at 2048 m (altitude) and 490 m (baseline); and between the oxygen and sham oxygen treatment periods at 2028 m. | Day 2 at 2048 m | 
| Perceived exertion | Difference in the perceived exertion rated with the BORG CR10 scale at the end of the 6 min walk between measurements at 2048 m (altitude) and 490 m (baseline); and between the oxygen and sham oxygen treatment periods at 2028 m. | Day 3 at 2048 m | 
| Severe hypoxemia | Number of participants in whom arterial oxygen saturation measured by pulse oximetry is less than 75% for more than 30 min during the sojourn at 2048 m (altitude) and 490 m (baseline); and during the oxygen and sham oxygen treatment periods at 2028 m. | Day 1 to 3 at 2048 m | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Pulmonary hypertension, Interstitial lung disease, Pulmonary fibrosis