title: Urbanization and Daily Exposure to Biomass Fuel Smoke Both Contribute to Chronic Bronchitis Risk in a Population with Low Prevalence of Daily Tobacco Smoking.
abstract: OBJECTIVE
  Risk factors beyond tobacco smoking associated with chronic bronchitis are not well understood. We sought to describe the prevalence and risk factors of chronic bronchitis across four distinct settings in Peru with overall low prevalence of tobacco smoking yet varying degrees of urbanization, daily exposure to biomass fuel smoke and living at high altitude.
  
  
  METHODS
  We analyzed data of 2,947 participants from rural and urban Puno, Lima and Tumbes including spirometry, blood samples, anthropometry and administered questionnaires about respiratory symptoms. We used multivariable Poisson regression to assess biologic, socioeconomic and environmental risk factors associated with chronic bronchitis.
  
  
  RESULTS
  Overall prevalence of chronic bronchitis was 5.9% (95%CI 5.1%-6.9%) with variation by setting: prevalence was lower in semi-urban Tumbes (1.3%) vs. highly urbanized Lima (8.9%), urban Puno (7.0%) and rural Puno (7.8%; p < 0.001). Chronic bronchitis was more common among participants with vs. without COPD based on FEV1/FVC< LLN (12.1% vs 5.6%, p < 0.01) and it was associated with increased reporting of dyspnea on exertion (p < 0.001), hospitalization (p = 0.003) and workdays missed due to respiratory symptoms (p < 0.001). Older age (Prevalence ratio [PR] = 1.23 for each 10-years of age, 95%CI 1.09-1.40) past history of asthma (PR = 2.87, 95%CI 1.80-4.56), urbanization (PR = 3.34, 95%CI 2.18-5.11) and daily exposure to biomass fuel smoke (PR = 2.00, 95%CI 1.30-3.07) were all associated with chronic bronchitis.
  
  
  CONCLUSIONS
  We found important variations in the prevalence of chronic bronchitis across settings. Prevalence increased with both urbanization and with daily exposure to biomass fuel smoke. Having chronic bronchitis was also associated with worse patient-centered outcomes including dyspnea, hospitalization and missed workdays.
authors.affiliation: a Division of Pulmonary and Critical Care, School of Medicine , Johns Hopkins University , Baltimore , Maryland , USA.
authors.forename: Catherine H
authors.initials: CH
authors.lastname: Miele
authors.affiliation: a Division of Pulmonary and Critical Care, School of Medicine , Johns Hopkins University , Baltimore , Maryland , USA.|b Program in Global Disease Epidemiology and Control, Department of International Health, Bloomberg School of Public Health , Johns Hopkins University , Baltimore , Maryland , USA.
authors.forename: Devan
authors.initials: D
authors.lastname: Jaganath
authors.affiliation: c CRONICAS Center of Excellence for Chronic Diseases , Universidad Peruana Cayetano Heredia , Lima , Peru.|d Departamento de Medicina, Escuela de Medicina , Universidad Peruana Cayetano Heredia , Lima , Peru.
authors.forename: J Jaime
authors.initials: JJ
authors.lastname: Miranda
authors.affiliation: c CRONICAS Center of Excellence for Chronic Diseases , Universidad Peruana Cayetano Heredia , Lima , Peru.
authors.forename: Antonio
authors.initials: A
authors.lastname: Bernabe-Ortiz
authors.affiliation: b Program in Global Disease Epidemiology and Control, Department of International Health, Bloomberg School of Public Health , Johns Hopkins University , Baltimore , Maryland , USA.
authors.forename: Robert H
authors.initials: RH
authors.lastname: Gilman
authors.affiliation: b Program in Global Disease Epidemiology and Control, Department of International Health, Bloomberg School of Public Health , Johns Hopkins University , Baltimore , Maryland , USA.
authors.forename: Caroline M
authors.initials: CM
authors.lastname: Johnson
authors.affiliation: a Division of Pulmonary and Critical Care, School of Medicine , Johns Hopkins University , Baltimore , Maryland , USA.
authors.forename: Gregory B
authors.initials: GB
authors.lastname: Diette
authors.affiliation: a Division of Pulmonary and Critical Care, School of Medicine , Johns Hopkins University , Baltimore , Maryland , USA.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Wise
authors.affiliation: a Division of Pulmonary and Critical Care, School of Medicine , Johns Hopkins University , Baltimore , Maryland , USA.|b Program in Global Disease Epidemiology and Control, Department of International Health, Bloomberg School of Public Health , Johns Hopkins University , Baltimore , Maryland , USA.
authors.forename: William
authors.initials: W
authors.lastname: Checkley
mesh_terms: D000328:Adult; D000393:Air Pollutants / Q000009:adverse effects*; D018533:Biomass; D029481:Bronchitis, Chronic / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010568:Peru / Q000453:epidemiology; D015995:Prevalence; D012307:Risk Factors; D012424:Rural Population; D012907:Smoking / Q000009:adverse effects* / Q000453:epidemiology; D013147:Spirometry; D014507:Urbanization / Q000639:trends*
chemical_list: D000393:Air Pollutants
keywords: COPD; Peru; biomass fuel; chronic bronchitis; pollution; respiratory disease; tobacco; urbanization