Breast cancer risk reduction: the upside of migraines?

That splitting headache that feels like your skull is about to crack open. Combine that with premenstrual cramps. That is something that many women have to suffer through at least once a month. However, it seems that there is a silver lining to migraines. Those who suffer from it have a much lower risk of developing breast cancer.

Researchers at the Hutchinson Cancer Research Center looked at more than 4,500 women with and without breast cancer and followed them up on lifestyle including incidence of migraines. The women who participated in this latest study were screened based on the following inclusion criteria:

• aged 34 to 64 years old (pre- and postmenopausal)
• never drank
• never smoked
• didn’t use hormones

The study results indicate that a clinical diagnosis of migraine is correlated to a reduction for risk of the most common subtypes of breast cancer, e.g. the estrogen-receptor and/or progesterone-receptor positive breast cancer.

This is not the first study to suggest the link between migraine and breast cancer risk. However, the previous studies had included a smaller number of participants (small sample size) and did not strictly screen them for lifestyle behaviours (e.g. alcohol consumption, smoking) that can contribute to both migraines and breast cancer development. This new study ruled out all these confounding factors but the association remains the same.

According to researcher and breast cancer epidemiologist Dr. Christopher Li

“We were able to look at whether this association was seen among both pre-menopausal and post menopausal women. In breast cancer this is relevant because there are certain risk factors that are different between older and younger women. In this study we saw the same reduction in breast cancer risk associated with a migraine history regardless of age.”

The how’s and the why’s are not fully understood but they probably have something to do with the circulating hormones in a woman’s body.

“Migraines seem to have a hormonal component in that they occur more frequently in women than in men, and some of their known triggers are associated with hormones. For example, women who take oral contraceptives – three weeks of active pills and one week of inactive pills to trigger menstruation – tend to suffer more migraines during their hormone-free week.”

This is why occurrence of migraines significantly decreases during pregnancy when a woman is in high estrogen state. Estrogen, too, is associated with certain types of breast cancer, especially the hormonally sensitive types.

However, the exact mechanism as to how hormones link migraine and breast cancer still needs to be closely investigated. The researchers are going one step further: they are investigating the type of migraines involved, including timing, intensity and duration, in the hope that with more knowledge will come understanding.

Now, you didn’t think you’d ever thank your lucky starts for those migraines, did you?