The findings of the study has strengthened the findings of the earlier research indicating regular use of aspirin might reduce the risk of so-called estrogen receptor-positive breast cancer, which makes up about three quarters of breast cancer cases.
Led by Gretchen Gierach of the National Cancer Institute, part of the National Institutes of Health, the study found that women who took aspirin daily cut their risk of developing this type of breast cancer by 16 percent. According to researchers, Estrogen receptor or ER-positive breast cancer is fueled by estrogen and aspirin may interfere with this hormone's activity.
In a telephone interview, Gierach said, "If aspirin is truly risk-reducing, it would be a very exciting finding. Even though it's a small reduction in relative risk, since ER-positive breast cancers are the more common types, if this result is confirmed to be true it could have potentially a big public health impact.”
The research studied about 127,000 women aged 51 to 72 from around the United States who were cancer-free when the study began. They found that about 18 percent of the women were daily aspirin users. They were tracked for seven years and about 4,500 of them developed breast cancer.
However, the study did not find any relationship between aspirin and the less-common estrogen receptor-negative breast cancer. It also did not find any protective effect in women who took aspirin less than daily.
The study is the latest one to suggest aspirin offers benefits beyond relieving headaches and body aches and reducing fevers. Aspirin is a common anti-inflammatory painkiller that can be used to relieve symptoms of arthritis and prevent second heart attacks and other ailments.