Zombies. That’s what postmenopausal hormone therapy (HT) reminds me of. For no matter how many times researchers link it to serious health problems (most notably, heart disease, stroke and breast cancer), HT keeps coming back. And coming back. And coming back.
It’s been on its relentless march for 40 years. Nothing — not even a large randomized controlled trial that had to be halted early because of the unexpected risks it uncovered — can stop it, it seems. (The halted study was the 2002 Women’s Health Initiative, or WHI.)
On Friday, HT took yet another blow. First some background: In recent years, the pharmaceutical industry has been somewhat successful in persuading doctors and women that it was probably OK to use HT for a short period of time around menopause to help with hot flashes and night sweats (which are really the only two reasons left to take these drugs). This is known as the “timing theory.” It claims that the findings from the WHI were biased because the average age of women in the study was 63, an age when you’d expect to see more heart disease and breast cancer.
Actually, in terms of breast cancer, the WHI did find a link between early use of HT and an increased risk of breast cancer. And a study published Friday in the Journal of the National Cancer Institute appears to confirm that link. It found that women who use hormones around the time of menopause are at greater relative risk of developing breast cancer than those who wait for five years or more.
Of course, if these findings hold up, it makes the market for HT almost nonexistent. For if you wait five years or more to take the hormones, you’ll probably be over the worse of the hot flashes and night sweats — but you’ll still be faced with HT’s other life-threatening side effects: heart disease and stroke.
This study, which used data from Britain’s Million Women Study (MWS), has its limitations. It’s an observational study, which can show only an association between two things, not a cause and effect. The women who participated (unlike those in the WHI study) were not randomly assigned to take HT or a placebo. They took (or didn’t take) the drugs for their own reasons — and underlying those reasons may be some as-yet-unknown factor that explains the breast-cancer-related difference in health outcomes. In addition, women who take hormones tend to have more mammograms — another factor that may have influenced the outcomes.
Still, as two cancer researchers note in an editorial that accompanies the study, these findings add support to the WHI’s earlier findings that “[w]omen who begin hormone therapy closer to menopause, as is the current common clinical practice, have a greater breast cancer risk than those beginning use further from menopause.”
Oh, and here’s some news that may help women take a more positive view of hot flashes: Researchers at the Fred Hutchinson Cancer Research Center reported earlier this month that women who have the most hot flashes may also have the lowest relative risk of developing breast cancer. These findings suggest (as does other research) that the drop in hormones after menopause may be protective.
Not that any of these findings will have an effect on HT’s zombie-like march. I’m already grabbing my popcorn and waiting for the next sequel to begin.
