It’s not gonna’ kill you to take hormone replacement

It’s not going to kill you to take hormone replacement therapy.

That’s the take home message from the latest analysis of the Women’s Health Initiative, the largest and longest randomized trial of hormone replacement therapy (HRT) in menopausal women.

After almost 18 years of follow up in the WHI, there was no increase in overall mortality, including death rates from cancer, in women taking HRT for up to 5.6 years (estrogen plus progestin) or 7.2 years (estrogen alone). There was a non-significant reduction in mortality among those who started HRT between ages 50 and 59, the group most likely to be prescribed hormone therapy for menopausal symptoms.

I’ve blogged before about the results and limitations of the WHI, which found, on balance, that the health risks of HRT (breast cancer, blood clots, stroke) about equaled its health benefits (protection against colon cancer and osteoporosis). The study (and the US Preventive Services Task Force) concluded that there was no reason for women to take HRT for preventive health reasons.

The biggest criticism of the WHI was that 70% of its participants were 10 or more years post-menopausal. The study did not include women most likely to benefit from taking HRT – those with hot flashes, night sweats, insomnia and other menopausal symptoms – or enough women in the 50-59 year age group. These women start HRT at menopause, not a decade or more after it’s over. In this younger group, more recent research suggests there may be a reduction in heart disease risk not captured by the WHI. Or not. It’s an ongoing debate among health experts not likely to be decided very soon.

In the meantime, millions of women enter menopause every year, some of them with significant symptoms that impact the quality of their life (and sleep), who must decide whether or not to use HRT to treat their symptoms.

For these women, this newest update from the WHI is reassuring.

The breast cancer mortality data from the WHI are complicated, and based on a small number of cases in the study population. Let’s just say there was no statistical increase in deaths from breast cancer among users of estrogen and progestin. Since the breast cancers occuring in HRT users are not inherently less aggressive, its more likely the lack of increased breast cancer mortality is because most breast cancers are not lethal, while those that might become lethal are effectively treated. Paradoxically, there was a significant decrease in breast cancer mortality among users of estrogen alone, perhaps related to the fact that estrogen, when taken after a long hiatus, actually inhibits breast cancer growth. (I told you, it’s complicated. You can read more about this here.)

Will this new information matter to women deciding about using HRT?

The use of HRT has plummeted in the years since the WHI results were published in 2002.

In my practice, the reason for the decline is clear – women don’t want to increase their chances of getting breast cancer, however small that increased risk may be.

I tell my patients this : “If you take HRT for 20 years, your risk of breast cancer will be about 1% higher. Use it for 2-3 years for menopausal symptoms, and that increased risk is less than a quarter of a percent”.

After considering this, the majority of women thank me for the information, and decline to use estrogen. Their symptoms are just not bad enough to entertain even that small a breast cancer risk. (I’m happy to prescribe HRT or non-hormonal therapies for those who opt to use them.)

This new study won’t change that conversation much, but I will now add that taking HRT for a few years around menopause to alleviate its symptoms will not increase mortality. I’ll also tell them that the data on breast cancer mortality, while complicated, seem to suggest no overall impact. That’s most likely because the overwhelming majority of breast cancers are not lethal, either due to their inherent behavior or our improved treatments.

I’m curious to see if this changes the choices they make.


More Reading on Menopause and HRT 

2 Responses to It’s not gonna’ kill you to take hormone replacement

  1. Hi, I am always interested in what you have to say about HRT, thanks for this one. Small complaint: the link for “Vaginal Estrogen” is wrong. Could you post the correct link? Thanks.

Leave a Reply