19 may 2016

Alcohol Use and Breast Cancer Survival among Participants in the Women’s Health Initiative

BACKGROUND: Alcohol increases the risk of breast cancer even at moderate levels of intake. However, the relationship between alcohol consumption and mortality among breast cancer patients is less clear.

METHODS: This study included women from the Women's Health Initiative observational study and randomized trial diagnosed with breast cancer (n = 7,835). Cox proportional hazards regression was used to estimate adjusted HRs and 95% confidence intervals (CI) for overall and breast cancer-specific (BCS) mortality associated with drinking alcohol before or after a breast cancer diagnosis. We also assessed whether changes in drinking habits after diagnosis are related to mortality.

RESULTS: Women who were consuming alcohol prior to their breast cancer diagnosis had a nonstatistically significant 24% (95% CI, 0.56-1.04) reduced risk of BCS mortality and a 26% (95% CI, 0.61-0.89) reduced risk of all-cause mortality. Some variation was observed by estrogen receptor (ER) status as alcohol consumption was associated with a 49% (95% CI, 0.31-0.83) reduced risk of BCS mortality among ER- patients with no change in risk observed among ER+ patients (HR = 0.97; 95% CI, 0.31-1.54), though the difference between these risks was not statistically significant (P for interaction = 0.39). Postdiagnosis alcohol consumption, and change in consumption patterns after diagnosis, did not appear to be associated with all-cause or BCS mortality.

CONCLUSION: In this large study, consumption of alcohol before or after breast cancer diagnosis did not increase risks of overall or cause-specific mortality.

IMPACT: Coupled with existing evidence, alcohol consumption is unlikely to have a substantial impact on mortality among breast cancer patients. Cancer Epidemiol Biomarkers Prev; 1-6. (c)2016 AACR.

Additional Info

  • Authors

    Li C.I.; Lowry S.J.; Kapphahn K.; Chlebowski R.
  • Issue

    Cancer Epidemiol Biomarkers Prev. 2016 May 19. [Epub ahead of print]
  • Published Date

    19 may 2016