Hormone Therapy And The Progression Of Coronary-Artery Atherosclerosis In Postmenopausal Women
Two recent studies were reported in the same issue of the New England Journal
of Medicine (8/7/03) looking at the relationship between hormone therapy
(HT) and cardiovascular disease in menopausal women. Yesterday, we discussed
the results of the National Institutes of Health (NIH) Women's Health Initiative
(WHI) which showed an increased risk of coronary heart disease in healthy
postmenopausal women who took combined estrogen plus progesterone for more
than 5 years. Today we'll address the second study on a similar topic by the
Women's Estrogen-Progestin Lipid-Lowering Hormone Atherosclerosis Regression
Trial Research Group. This study evaluated postmenopausal women who
already had preexisting coronary artery disease,to see if a treatment regimen
of 17-estradiol (the
endogenous estrogen molecule) either alone or when given concurrently with medroxyprogesterone
acetate (Provera™) could slow the progression of atherosclerosis. Previous
studies have shown that a treatment regimen of conjugated equine estrogen with
or without continuous administration of medroxyprogesterone acetate (Premarin™
or Prempro™) could not slow the progression of atherosclerosis in similar
women. The question here was whether a different formulation of estrogen would
make a difference. It did not.
This study was a double-blind, placebo-controlled trail in 226 postmenopausal
women whose average age was 63.5 years and who had at least one coronary-artery
lesion. The participants were randomly assigned to groups who received either
their usual care (the "control group"), estrogen therapy with micronized 17-estradiol
alone (the "estrogen group"), or 17-estradiol
plus sequentially administered medroxyprogesterone acetate (the "combination
estrogen-progestin group"). In all patients the low-density lipoprotein (LDL)
cholesterol level was reduced to a target of less than 130 mg per deciliter.
The researchers were primarily interested in the average per-participant change
in coronary artery stenosis (narrowing) between angiograms taken at the beginning
and end of the study.
After an average of 3.3 years, the average change in the percent stenosis was
1.89 percentage points in the control group, 2.18 in the estrogen group, and
1.24 in the estrogen-progestin group. After statistical analysis, the researchers
concluded that in older postmenopausal women with established coronary-arteryathero
sclerosis, 17-estradiol
either alone or with sequentially administered medroxyprogesterone acetate had
no significant effect on the progression of atherosclerosis.
Created: 9/9/2003  - Donnica Moore, M.D.