Migraine Subjects Are Less Likely to Develop Breast Cancer

A year ago a small study suggested that there was a 33% lower risk of two types of breast cancer in women with migraine. The study, however, could not exclude possible bias from common factors (like medication use) influencing the results; this led the authors to call for additional studies. Now a much larger study has been completed, and reported in the journal Cancer Epidemiology, Biomarkers & Prevention.

Data from the Women’s Contraceptive and Reproduction Experiences Study was used for analysis; there were 4,568 women with invasive breast cancer and 4,678 cancer-free controls. A history of migraine was obtained from structured in-person interviews, along with comprehensive information on lifestyle, medications, and other health factors.

A history of clinically diagnosed migraine was linked to a 26% reduced risk of breast cancer overall. The reduction was similar for postmenopausal and premenopausal women, and was uninfluenced by use of prescription migraine meds, alcohol intake, hormone therapy, or smoking. Hormone receptor-positive tumors were more closely linked to migraine than hormone receptor-negative tumors, supporting the view that the link between the findings is hormonal in nature.

I must emphasize that women with migraine shouldn't read these results as meaning they have no risk of developing breast cancer – far from it. Reduced risk doesn’t mean no risk, so don’t drop routine screening!