Lung cancer risk in never-smokers: a population-based case-control study of epidemiologic risk factors

BMC Cancer. 2010 Jun 14;10:285. doi: 10.1186/1471-2407-10-285.

Abstract

Background: We conducted a case-control study in the greater Toronto area to evaluate potential lung cancer risk factors including environmental tobacco smoke (ETS) exposure, family history of cancer, indoor air pollution, workplace exposures and history of previous respiratory diseases with special consideration given to never smokers.

Methods: 445 cases (35% of which were never smokers oversampled by design) between the ages of 20-84 were identified through four major tertiary care hospitals in metropolitan Toronto between 1997 and 2002 and were frequency matched on sex and ethnicity with 425 population controls and 523 hospital controls. Unconditional logistic regression models were used to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI) for the associations between exposures and lung cancer risk.

Results: Any previous exposure to occupational exposures (OR total population 1.6, 95% CI 1.4-2.1, OR never smokers 2.1, 95% CI 1.3-3.3), a previous diagnosis of emphysema in the total population (OR 4.8, 95% CI 2.0-11.1) or a first degree family member with a previous cancer diagnosis before age 50 among never smokers (OR 1.8, 95% CI 1.0-3.2) were associated with increased lung cancer risk.

Conclusions: Occupational exposures and family history of cancer with young onset were important risk factors among never smokers.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Age of Onset
  • Aged
  • Aged, 80 and over
  • Air Pollution, Indoor / adverse effects
  • Case-Control Studies
  • Chi-Square Distribution
  • Female
  • Genetic Testing
  • Humans
  • Logistic Models
  • Lung Neoplasms / epidemiology*
  • Lung Neoplasms / etiology*
  • Male
  • Middle Aged
  • Occupational Exposure
  • Odds Ratio
  • Ontario / epidemiology
  • Pedigree
  • Respiratory Tract Diseases / complications
  • Respiratory Tract Diseases / epidemiology
  • Risk Assessment
  • Risk Factors
  • Tobacco Smoke Pollution / adverse effects
  • Urban Health
  • Young Adult

Substances

  • Tobacco Smoke Pollution