title: The exposure-time-response relationship between occupational asbestos exposure and lung cancer in two German case-control studies.
abstract: BACKGROUND
  Numerous studies have been carried out to evaluate the association between lung cancer and occupational asbestos exposure. However, the effects of timing of exposure have not been analyzed thoroughly.
  
  
  METHODS
  Two German case-control studies with data on occupational asbestos exposure histories have been pooled. Duration of work in potentially asbestos exposed jobs and two derived weighted exposure measures are analyzed together with time since last exposure. A spline function is used to model the effect of time since exposure.
  
  
  RESULTS
  The odds ratios (OR) and corresponding 95% confidence intervals were 1.8 (1.2, 2.7) and 2.4 (1.7, 3.4) for subjects having worked for 3 to 7 years and 8 or more years, respectively, in a job with potential asbestos exposure compared to never-exposed. Based on an evaluation of time since last exposure, the OR decreased significantly to about one-half after more than 20 years since exposure ceased. Using a spline function, applied to workers' complete exposure histories, the effect of an increment of exposure is greatest 10-15 years after that exposure was received.
  
  
  CONCLUSIONS
  In contrast to previous indications, the risk of lung cancer increases soon after asbestos exposure, with its maximum effect from 10 to 15 years after the exposure was received.
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD 20892-7244, USA. hauptmann@nih.gov
authors.forename: Michael
authors.initials: M
authors.lastname: Hauptmann
authors.forename: Hermann
authors.initials: H
authors.lastname: Pohlabeln
authors.forename: Jay H
authors.initials: JH
authors.lastname: Lubin
authors.forename: Karl-Heinz
authors.initials: KH
authors.lastname: Jöckel
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Ahrens
authors.forename: Irene
authors.initials: I
authors.lastname: Brüske-Hohlfeld
authors.forename: H -Erich
authors.initials: H-
authors.lastname: Wichmann
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001194:Asbestos / Q000009:adverse effects*; D002273:Carcinogens / Q000009:adverse effects*; D016022:Case-Control Studies; D005858:Germany / Q000453:epidemiology; D006801:Humans; D016015:Logistic Models; D008175:Lung Neoplasms / Q000453:epidemiology* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D009784:Occupational Diseases / Q000453:epidemiology* / Q000209:etiology; D016273:Occupational Exposure / Q000009:adverse effects*; D009790:Occupations / Q000706:statistics & numerical data; D016017:Odds Ratio; D012307:Risk Factors; D016540:Smoking Cessation; D013997:Time Factors
chemical_list: D002273:Carcinogens; D001194:Asbestos