Menopause Symptoms Associated with Reduction in Breast Cancer Risk

According to a new study by researchers at the Fred Hutchinson Cancer Research Center, postmenopausal women who experience hot flushes and other menopause symptoms may have a 50% lower risk of developing the most common forms of breast cancer. This study is the first to examine the relationship between menopausal symptoms and breast cancer risk.

The group, led by Christopher I. Li, MD, PhD, a breast cancer epidemiologist in the Hutchinson Center’s Public Health Sciences Division, interviewed 1,437 postmenopausal Seattle-area women, 988 of whom had been previously diagnosed with breast cancer and 449 of whom had not. The women were asked about perimenopausal and menopausal symptoms ranging from hot flushes, night sweats, and insomnia to vaginal dryness, irregular or heavy menstrual bleeding, depression and anxiety.

The researchers found that those who had experienced menopause symptoms showed a 40% to 60% reduction in the risk of invasive ductal and invasive lobular carcinoma-the two most common types of breast cancer. The association between these symptoms and decreased cancer risk did not change even after the researchers accounted for other factors known to boost breast cancer risk, such as obesity and use of hormone replacement therapy.

The protective effect also appeared to increase along with the number and severity of menopausal symptoms, according Dr. Li. “In particular, we found that women who experienced more intense hot flushes-the kind that woke them up at night-had a particularly low risk of breast cancer.”

“While menopausal symptoms can certainly have a negative impact on quality of life, our study suggests that there may be a silver lining if the reduction in breast cancer risk is confirmed in future studies,” Li said. “If these findings are confirmed, they have the potential to improve our understanding of the causes of breast cancer and improve approaches to preventing this disease.”

Go here to read the full paper, which is published online first and slated for the February issue of Cancer Epidemiology Biomarkers and Prevention.