title: Previous pulmonary diseases and risk of lung cancer in Gansu Province, China.
abstract: BACKGROUND
  Although active smoking is well established as the main cause of lung cancer, there is accumulating evidence that history of prior lung diseases may be an independent risk factor for lung cancer.
  
  
  METHODS
  A population-based case-control study in Gansu Province, China identified 886 lung cancer cases (656 male, 230 female) diagnosed between January 1994 and April 1998. A standardized interview collected information on a variety of potential risk factors including a history of physician-diagnosed non-malignant lung diseases (pulmonary tuberculosis, chronic bronchitis/emphysema, asthma, pneumonia), age and year in which each condition was first diagnosed, and any therapy or hospitalization received.
  
  
  RESULTS
  Pulmonary tuberculosis (odds ratio [OR] = 2.1, 95% CI : 1.4-3.1) and chronic bronchitis/emphysema (OR = 1.4, 95% CI : 1.1-1.8) were associated with increased risk of lung cancer, after adjustment for active smoking and socioeconomic status. The OR for asthma (OR = 1.4, 95% CI : 0.9-2.1) and pneumonia (OR = 1.5, 95% CI : 1.0-2.3) were also elevated. The risk of lung cancer remained significant for pulmonary tuberculosis and chronic bronchitis/emphysema when analysis was limited to the pathologically confirmed cases and self-responders.
  
  
  CONCLUSIONS
  This study provides additional evidence that previous pulmonary tuberculosis and chronic bronchitis/emphysema are causally related to lung cancer, although the precise mechanism is still unclear. The results for asthma and pneumonia, while suggestive of a positive association, did not reach the traditional level of statistical significance and should be interpreted with caution.
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD 20892, USA. brennera@mail.nih.gov
authors.forename: A V
authors.initials: AV
authors.lastname: Brenner
authors.forename: Z
authors.initials: Z
authors.lastname: Wang
authors.forename: R A
authors.initials: RA
authors.lastname: Kleinerman
authors.forename: L
authors.initials: L
authors.lastname: Wang
authors.forename: S
authors.initials: S
authors.lastname: Zhang
authors.forename: C
authors.initials: C
authors.lastname: Metayer
authors.forename: K
authors.initials: K
authors.lastname: Chen
authors.forename: S
authors.initials: S
authors.lastname: Lei
authors.forename: H
authors.initials: H
authors.lastname: Cui
authors.forename: J H
authors.initials: JH
authors.lastname: Lubin
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D002681:China / Q000453:epidemiology; D016001:Confidence Intervals; D005260:Female; D006801:Humans; D008171:Lung Diseases / Q000453:epidemiology*; D008175:Lung Neoplasms / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio