Today we’re talking on menopause once more with Dr. Renee Eger, assistant professor and clinician educator at the Warren Alpert Medical School of Brown University. We spend the second half of our menopause series reviewing HRT and the Women’s Health Initiative (WHI).
You can read more about the WHI here. The study really is two study methodologies in one: there were up to three randomized-controlled trial arms, and an observational arm. The components concerning HRT are dealt with through one of the RCTs.
The RCT dealing with HRT enrolled women into one of three arms: a placebo, an estrogen-only arm in patients without a uterus, or and estrogen-progesterone combination in patients with a uterus. The study was halted at 5.2 years in the E-P arm due to an increase in coronary heart disease, breast cancer, VTE, and stroke, which outweighed a benefit noted in colorectal cancer and fracture risk. The E-alone arm was stopped at 6.8 years average follow up, when the risk of heart disease was found not to be different than placebo.
Subsequent studies, including the Heart and Estrogen/progestin Replacement Study (HERS) have demonstrated at least that E-P and E should not be used for primary or secondary prevention of coronary disease, and thus HRT should not be prescribed for these indications. However, many benefits are particularly pronounced in younger patients using HRT. Thus, the position of the North American Menopause Society (NAMS) reads (emphasis ours):
“For women aged younger than 60 years or who are within 10 years of menopause onset and have no contraindications, the benefit-risk ratio is most favorable for treatment of bothersome VMS and for those at elevated risk for bone loss or fracture.
”For women who initiate HT more than 10 or 20 years from menopause onset or are aged 60 years or older, the benefit-risk ratio appears less favorable because of the greater absolute risks of coronary heart disease, stroke, venous thromboembolism, and dementia.
”Longer durations of therapy should be for documented indications such as persistent VMS or bone loss, with shared decision making and periodic reevaluation. For bothersome GSM symptoms not relieved with over-the-counter therapies and without indications for use of systemic HT, low-dose vaginal estrogen therapy or other therapies are recommended.”