Smoking and alcohol consumption in relation to risk of triple-negative breast cancer in a cohort of postmenopausal women

Cancer Causes Control. 2011 May;22(5):775-83. doi: 10.1007/s10552-011-9750-7. Epub 2011 Mar 1.


Purpose: Little is known about the risk factors for triple-negative breast cancer (TNBC), which has a worse prognosis compared to hormone receptor-positive breast cancer. We examined the association of smoking and alcohol intake with TNBC and estrogen receptor-positive (ER+) breast cancer.

Methods: Among 148,030 women enrolled in the Women's Health Initiative, 300 TNBC cases and 2,479 ER+ cases were identified over a median of 8.0 years of follow-up. Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (95% CI).

Results: Cigarette smoking was not associated with TNBC, whereas drinkers had reduced risk compared to never drinkers. In contrast, both exposures showed slight positive associations with ER+ breast cancer: for women with ≥ 40 pack-years of smoking, the HR was 1.24, 95% CI 1.06-1.44; for women consuming ≥ 7 servings of alcohol per week, the HR was 1.26, 95% CI 1.06-1.50. Intakes of wine and hard liquor were also significantly positively associated with ER+ breast cancer.

Conclusions: These findings from a large cohort of postmenopausal women suggest that smoking and alcohol consumption are not associated with increased risk of TNBC, but may be modestly associated with increased risk of ER+ breast cancer.

MeSH terms

  • Aged
  • Alcohol Drinking / adverse effects
  • Alcohol Drinking / epidemiology*
  • Breast Neoplasms / epidemiology*
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / pathology
  • Cohort Studies
  • Female
  • Humans
  • Middle Aged
  • Postmenopause
  • Prognosis
  • Receptors, Estrogen / metabolism
  • Risk Factors
  • Smoking


  • Receptors, Estrogen