Simple blood test could indicate higher risk for coronary events in women after post-menopausal hormone therapies

May 22 2008

A research study has found that a simple blood test may indicate whether post-menopausal hormone therapies present an elevated risk of a heart attack.

The study, part of the Women's Health Initiative (WHI), sponsored by the National Heart, Lung and Blood Institute of the National Institutes of Health, was conducted in 40 centers nationwide and included 271 cases of coronary heart disease in the first four years of the trials of estrogen alone and of estrogen plus progestin. Corresponding author Paul F. Bray, M.D., the Thomas Drake Martinez Cardeza Professor of Medicine, Director, Division of Hematology at Jefferson Medical College of Thomas Jefferson University and his co-authors report their findings in the June 1st edition of the American Journal of Cardiology.

"Because studies on hormone therapy have shown that they may increase heart attacks and strokes, many women have been reluctant to use this treatment," said Bray. "However, because hormones remain the most effective remedy for managing post-menopausal symptoms, such as hot flashes and night sweats, many women wanted to take this therapy, but have struggled with the decision because they feared the potential side effects. We found that a simple and widely used blood test may be useful to advise women if they are at an increased risk of a heart attack while undergoing hormone therapy."

The study looked at levels of blood lipids and high sensitivity C-reactive protein (hsCRP) in women who did not have any previous cardiovascular disease. The results indicate those who entered the study with favorable cholesterol levels were not at increased risk of developing heart problems while taking hormones (estrogen alone or estrogen plus progestin), whereas women with unfavorable cholesterol levels were at a greater risk of having heart related complications. Specifically, women with ratios of "bad" cholesterol to "good" cholesterol less than 2.5 did not appear to be at an increased heart disease risk when using hormone therapy. On the other hand, it is known that women with higher ratios of "bad" to "good" cholesterol were at higher risk of coronary heart disease, and this study shows that risk is magnified if they take hormone therapy. Elevated hsCRP appeared to predict higher risk in women taking estrogen, but not in women taking estrogen plus progestin compared to a placebo.

"This report only considered the effects of hormone therapy on coronary disease outcomes," added Bray. "Instead of genetic testing or another more complicated test, we wanted to find a simple and effective way to assess the heart risk of hormone therapy. However, it should be noted that the WHI investigators have not found this test helpful in predicting the risk of stroke due to hormone therapy. It should also be noted that hormones affect a number of major organs so patients must consider the totality of health risks and benefits, including coronary heart disease, stroke, venous thrombosis, breast cancer, fractures and gall bladder disease. The findings do not change the current recommendation that hormone therapy should not be used for prevention of coronary heart disease - for prevention, women should focus on preventing and treating known risk factors such as high blood cholesterol and high blood pressure, and on avoiding smoking. Hormones should be used for the shortest time and lowest dose need to obtain symptom relief."