Patients With Chronic Obstructive Pulmonary Disease At Altitude

Effect of Altitude on Exercise Performance of Patients With Chronic Obstructive Lung Disease

The purpose of this study is to investigate the effect of a stay at moderate altitude on exercise performance of patients with chronic obstructive lung disease.

Patients with moderate to severe COPD living below 800 m, will be recruited to participate in a randomized cross-over field trial evaluating the hypothesis that exercise capacity during a 4 day sojourn at moderate altitude is reduced in comparison to low altitude. Outcomes will be assessed during 2 days in Zurich (490 m, low altitude baseline), 2 days at Davos Clavadel (1650 m), and 2 days at Davos Jakobshorn (2590 m). The main outcome is the 6 minute walk distance.

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