title: Prevalence of COPD in five Colombian cities situated at low, medium, and high altitude (PREPOCOL study).
abstract: BACKGROUND
  The prevalence of COPD in Colombia is unknown. This study aimed to investigate COPD prevalence in five Colombian cities and measure the association between COPD and altitude.
  
  
  METHODS
  A cross-sectional design and a random, multistage, cluster-sampling strategy were used to provide representative samples of adults aged >or= 40 years. Each participant was interviewed (validated Spanish version of the Ferris Respiratory Questionnaire) and performed spirometry before and after 200 microg of inhaled salbutamol, using a portable spirometer according to American Thoracic Society recommendations. COPD definitions were as follows: (1) spirometric: fixed ratio (primary definition): FEV1/FVC < 70% after bronchodilator; (2) medical: a diagnosis of chronic bronchitis, emphysema, or COPD made by a physician; (3) clinical: cough and phlegm >or= 3 months every year during >or= 2 consecutive years (chronic bronchitis). Analysis was performed using statistical software.
  
  
  RESULTS
  A total of 5,539 orsubjects were included. The overall COPD prevalence using the primary definition (spirometric) was 8.9%, ranging from 6.2% in Barranquilla to 13.5% in Medellín. The prevalence measured by the spirometric definition was higher than medical (2.8%) and clinical (3.2%) definitions. After the logistic regression analysis, the factors related with COPD were age >or= 60 years, male gender, history of tuberculosis, smoking, wood smoke exposure >or= 10 years, and very low education level. There was a nonsignificant tendency toward larger prevalence with higher altitude.
  
  
  CONCLUSIONS
  COPD is an important health burden in Colombia. Additional studies are needed to establish the real influence of altitude on COPD prevalence.
authors.affiliation: Asociación Colombiana de Neumología y Cirugía de Tórax, Clínica Reina Sofía, Bogotá, Colombia. ascaballero@colsanitas.com
authors.forename: Andrés
authors.initials: A
authors.lastname: Caballero
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Torres-Duque
authors.forename: Claudia
authors.initials: C
authors.lastname: Jaramillo
authors.forename: Fabio
authors.initials: F
authors.lastname: Bolívar
authors.forename: Fernando
authors.initials: F
authors.lastname: Sanabria
authors.forename: Patricia
authors.initials: P
authors.lastname: Osorio
authors.forename: Carlos
authors.initials: C
authors.lastname: Orduz
authors.forename: Diana P
authors.initials: DP
authors.lastname: Guevara
authors.forename: Darío
authors.initials: D
authors.lastname: Maldonado
mesh_terms: D000328:Adult; D000368:Aged; D000531:Altitude; D003105:Colombia / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology*; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology; D013147:Spirometry; D014397:Tuberculosis, Pulmonary / Q000453:epidemiology