What’s the relationship between heart health and hormone therapy?

So glad you asked! You might be surprised to learn that, in spite of everything you’ve read about hormones, you should worry more about dying from heart disease than from breast cancer—even if you’ve had breast cancer. 

“Heart disease kills more than twice as many women as breast cancer does, even young women under the age of forty, and it kills four times as many women between the ages of sixty and seventy-nine,” write the authors of Estrogen Matters. And multiple reputable studies before and after 2002 have shown that hormone therapy (HT)  in postmenopausal women reduces the risk of “a coronary event” by about 50 percent; others show that estrogen reduces the risk of coronary artery disease in postmenopausal women by 40 – 50 percent, compared to women who didn’t take hormones. (There’s some debate over the way research is conducted—observational studies versus randomized controlled trials—which you can read all about in the book, if you’re interested. Personally, I’m satisfied that the research is sound.)

Talk to your doctor about the risks and benefits of hormone therapy specifically for you

The Women’s Health Initiative (WHI) study from 2002 first said that women on HT (but not estrogen-only therapy) had a slightly increased relative risk of “heart events.” But 70 percent of the women in that study were 60-79 years of age, many of whom had risk factors for heart disease and none of whom were excluded from the analysis because of those factors. 

WHI revised that finding in 2007, write the authors of Estrogen Matters, “now concluding that women who started HT within ten years of the onset of menopause actually reduced their risk of coronary artery disease, while those who started after that slightly increased their risk.” 

HT increases the risk to the heart in the first year of use and in older women because arteries become less elastic after menopause. Starting to take estrogen after a few years doesn’t reverse that, and it widens blood vessels, increasing blood flow to the heart.

What does all this mean to you? If you are under 60 or within 10 years of entering menopause (when you haven’t had a period for 12 consecutive months), talk to your doctor about whether the health benefits of HT outweigh any risks. The research shows that when you begin HT during that window, it significantly reduces coronary artery disease and overall mortality—possibly adding as many as three or four years to your lifespan, according to some experts. I think that possibility alone is worth a conversation with your doctor!