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