Occupation and breast cancer risk among Shanghai women in a population-based cohort study

Am J Ind Med. 2008 Feb;51(2):100-10. doi: 10.1002/ajim.20507.


Introduction: A total of 74,942 female subjects were recruited in a population-based cohort study in Shanghai, China between 1997 and 2000. We examined the relationship between occupation and breast cancer risk.

Methods: Cases were 586 women previously diagnosed with breast cancer at baseline and 438 women newly diagnosed with breast cancer during follow-up through December 2004. Eight controls were randomly selected for each case from cancer-free cohort members and frequency-matched to the cases by year of birth and age at diagnosis. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) of breast cancer risk associated with occupations, adjusting for established breast cancer risk factors.

Results: In the prevalent breast cancer data analysis, increased risks of breast cancer were associated with technicians in engineering/agriculture/forestry (OR = 1.6, CI: 1.0-2.4), teaching personnel (OR = 1.5, CI:1.1-2.0), tailoring/sewing workers (OR = 1.6, CI:1.0-2.7), and examiners/measurers/testers (OR = 1.5, CI:1.1-2.1) among those who started the jobs at least 20 years ago. Among incident breast cancer cases, significantly increased risks were associated with medical/health care workers (OR = 1.4, CI:1.0-2.0), administrative clerical workers (OR = 1.5, CI:1.0-2.4), postal/telecommunication workers (OR = 2.2, CI:1.0-5.5), and odd-job workers (OR = 1.7, CI:1.1-2.8) among those who started the jobs at least 20 years ago. The excess risks were found in both prevalent and incident cases for postal/telecommunication workers and purchasing/marketing personnel, although ORs reached only marginal significance.

Conclusions: This study suggests that white-collar professionals and several production occupations may be associated with an increased risk of breast cancer.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural

MeSH terms

  • Adult
  • Aged
  • Breast Neoplasms / epidemiology*
  • Case-Control Studies
  • China / epidemiology
  • Female
  • Health Surveys
  • Humans
  • Incidence
  • Middle Aged
  • Occupational Diseases / epidemiology*
  • Occupational Exposure / adverse effects*
  • Prevalence
  • Risk Assessment
  • Risk Factors
  • Surveys and Questionnaires
  • Women's Health