High altitude and chronic obstructive pulmonary disease prevalence: a casual or causal correlation?

Arch Bronconeumol. 2012 May;48(5):156-60. doi: 10.1016/j.arbres.2011.12.004. Epub 2012 Feb 15.
[Article in English, Spanish]


Introduction: Studies on the relationship of chronic obstructive pulmonary disease (COPD) prevalence and altitude have reported contrasting results. The aim of this COPD case-finding study was to include a larger number of geographical sites to determine if there is an association between altitude and COPD prevalence.

Patients and methods: Individuals aged 40 or older with known COPD risk factors, whether symptomatic or not, were referred by primary-care physicians. After obtaining written informed consent, they were invited to answer a questionnaire and undergo pre- and post-bronchodilator spirometry.

Results: Subjects were recruited in 27 Mexican cities, within an altitude range from 1 to 2,680 m above sea level. We found a weak (-0.31; P<.0001) although significant negative correlation between altitude and COPD prevalence. The COPD rate for cities located ≤1,000 m was 32.7% vs 16.4% for cities located >1,000 m (P<.0001); the rate for cities located at ≤2,000 m was 22.7% vs 15.6% for those >2,000 m; in the multiple logistic regression analysis, older age, male sex, tobacco habit, pack-years of smoking, years of exposure to biomass smoke and city altitude over sea level were significantly associated with COPD prevalence.

Conclusions: Our data shows a significant inverse correlation between prevalence/severity of COPD and altitude.

MeSH terms

  • Aged
  • Altitude*
  • Female
  • Humans
  • Male
  • Mexico
  • Middle Aged
  • Prevalence
  • Pulmonary Disease, Chronic Obstructive / epidemiology*
  • Pulmonary Disease, Chronic Obstructive / etiology*
  • Severity of Illness Index
  • Urban Health