Women who have had breast cancer can feel better about enjoying a glass of wine.
On the one hand, alcohol use is known to increase the risk of developing certain types of breast cancer. In fact, for each additional drink in an average day, the relative risk increases by seven percent, according to several previous studies.
However, a new study published today in the Journal of Clinical Oncology examined the effects of alcohol on breast cancer survivors, and found that moderate drinking may actually increase a woman’s chances of survival.
Polly Newcomb, Ph.D., a member of the Public Health Sciences Division and head of the Cancer Prevention Program at Fred Hutchinson Cancer Research Center, led the study.
"Our findings should be reassuring to women who have breast cancer because their past experience consuming alcohol will not impact their survival after diagnosis," Newcomb said in a press release.
The researchers looked at a cohort of breast cancer survivors, approximately 23,000 women who participated in the Collaborative Breast Cancer Study, which began in 1988. They also assessed data from a follow-up questionnaire given to about 5,000 cancer survivors, who were surveyed about their alcohol consumption habits after diagnosis.
Key Takeaways from the Study
“Women with a history of breast cancer may be concerned that their lifestyle choices before diagnosis may impact their prognosis,” said Newcomb. “They may wonder whether modifying these factors could improve their survival.”
The study showed no adverse association between moderate alcohol drinking and breast cancer survival. “We actually found that relative to nondrinkers, there was improved survival for moderate alcohol consumers,” Newcomb said.
Newcomb's findings highlight the benefits of moderate alcohol use (three to six drinks per week), compared to sobriety, especially with respect to the risk of heart disease that often accompanies a cancer diagnosis:
- Breast cancer survivors who drank alcohol before they were diagnosed were 15 percent less likely to die of breast cancer.
- Breast cancer survivors who drank alcohol before, but not after, they were diagnosed were 25 percent less likely to die from cardiovascular conditions.
- Breast cancer survivors who drank alcohol both before and after they were diagnosed were 39 to 50 percent less likely to die from cardiovascular conditions.
Why Do Heart Disease Risks Co-occur With Cancer?
Heart disease is the leading cause of death in the U.S., killing six times more women each year than breast cancer, according to the Women’s Heart Foundation.
Although other risk factors, such as high blood pressure and diabetes, contribute, recent studies have shown that chemotherapy can result in a seven percent greater risk of death from heart disease among breast cancer survivors.
According to the Newcomb study, “Cardiovascular disease is increasingly recognized as an important contributor to mortality among breast cancer survivors."
Heart disease in cancer patients is linked to the cardio-toxic and metabolic effects of some types of chemotherapy, which are known to weaken the heart muscle. New, targeted cancer treatments may reduce these risks.
And alcohol is known to help. There is a growing body of evidence to show that moderate alcohol consumption, especially consumption of red wine, decreases the risk of heart disease, regardless of whether a patient has had cancer.
“This study does provide support for a benefit of moderate alcohol intake for cardiovascular and overall survival in women with breast cancer, as observed in the general population as well,” says Newcomb.