Research published in the recent issue of Cancer Epidemiology, Biomarkers & Prevention concluded that postmenopausal women regularly using aspirin and other painkillers have lower estrogen levels than those not using these products and that may contribute to a decreased risk of breast or ovarian cancer.
Seven hundred forty postmenopausal women who participated in the Nurse’s Health Study were examined for an association between the use of aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs) and acetaminophen and concentrations of estrogens and androgens. Findings showed an inverse relationship between the frequency of painkiller use and estradiol, free estradiol, estrone sulfate and the ration of estradiol to testosterone.
Average estradiol levels were 10.5% lower among women regularly using aspirin or NSAIDs. In addition this group also showed 10.6% lower free estradiol levels, and 11.1% lower estrone sulfate levels. In addition, among regular users of any painkiller (aspirin, NSAIDs, or acetaminophen) the levels of these hormones were 15.2% lower (estradiol), 12.9% lower (free estradiol), and 12.6% lower (estrone sulfate).
Michael Thun, M.D. Vice-President Emeritus of epidemiology and surveillance research at the American Cancer Society said that the association of painkillers use and breast cancer risk is important but still unresolved. He further said that the results do not confirm a relationship between painkillers and lower circulating levels of estradiol but it is promising and further research is needed.
