Nocturnal Breathing and Sleep in Patients With Chronic Obstructive Pulmonary Disease Staying at Altitude

Study Overview
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Brief Summary
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The purpose of this study is to evaluate whether nocturnal breathing and sleep of patients with chronic obstructive pulmonary disease (COPD) are disturbed during a stay at moderate altitude.

Detailed Description
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This randomized cross-over trial evaluates the hypothesis that patients with chronic obstructive pulmonary disease experience nocturnal hypoxemia, periodic breathing and sleep disturbances when staying at moderate altitude. Sleep studies and clinical evaluations will be performed during 2 days in Zurich (490 m, low altitude baseline) and during 2 days at Davos Clavadel (1650 m), and 2 days at Davos Jakobshorn (2590 m).

Official Title
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Nocturnal Breathing and Sleep in Patients With Chronic Obstructive Pulmonary Disease Staying at Altitude

Conditions
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Chronic Obstructive Pulmonary Disease

Intervention / Treatment
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* Other: Altitude exposure


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: chronic obstructive pulmonary disease (COPD), GOLD grade 2-3 residents at low altitude (<800 m) Exclusion Criteria: Unstable condition, COPD exacerbation Mild (GOLD 1) or very severe COPD (GOLD 4) requirement for oxygen therapy at low altitude residence hypoventilation pulmonary hypertension 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

Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: A: low-intermediate-high altitude<br>Altitude exposure sequence A, 490-1650-2590m | Other: Altitude exposure<br>* Stay at different altitudes: 490, 1650, 2590 m<br>|
| Other: B: low-high-intermediate altitude<br>Altitude exposure sequence B, 490-2590-1650m | Other: Altitude exposure<br>* Stay at different altitudes: 490, 1650, 2590 m<br>|
| Other: C: intermediate-high-low altitude<br>Altitude exposure sequence C, 1650-2590-490m | Other: Altitude exposure<br>* Stay at different altitudes: 490, 1650, 2590 m<br>|
| Other: D: high-intermediate-low altitude<br>Altitude exposure sequence D, 2590-1650-490m | Other: Altitude exposure<br>* Stay at different altitudes: 490, 1650, 2590 m<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in mean nocturnal oxygen saturation from baseline measured at 490 m | mean nocturnal oxygen saturation measured by pulse oximetry | Change in mean nocturnal oxygen saturation from 490 m baseline during 2 days at 2590 m | 
| Change in apnea/hypopnea index from baseline measured at 490 m | apnea/hypopnea index measured by polysomnography | Change in apnea/hypopnea index from 490 m baseline during 2 days at 2590 m | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in mean nocturnal oxygen saturation from baseline measured at 490 m | apnea/hypopnea measured by polysomnography | Change in mean nocturnal oxygen saturation from 490 m baseline during 2 days at 1650 m | 
| Change in apnea/hypopnea index from baseline measured at 490 m | apnea/hypopnea index measured by polysomnography | Change in apnea/hypopnea index from 490 m baseline during stay at 1650 m | 
| Change in subjective sleep quality from baseline measured at 490 m | Visual analog scale of sleep quality | Change in subjective sleep quality from 490 m during 2 days at 2590 m | 
| Change in subjective sleep quality from baseline measured at 490 m | Visual analog scale of sleep quality | Change in subjective sleep quality from 490 m baseline during 2 days at 1650 m | 
| Change in reaction time from baseline measured at 490 m | psychomotor vigilance test reaction time | Change in reaction time from 490 m baseline during 2 days at 2590 m | 
| Change in reaction time from baseline measured at 490 m | Psychomotor vigilance test reaction time | Change in reaction time from 490 m baseline during 2 days at 1650 m |