Menopause and the Cardiovascular System
Dr. Ouyang has expertise in preventive cardiology, cardiovascular disease in women, and a number of other areas. Her research pursuits include gender differences in cardiovascular risk factors. Learn more about Dr. Ouyang.
Do menopausal women have an increased risk of cardiovascular disease?
A fair amount of research has connected menopause with cardiovascular disease, including risk factors such as rising LDL (bad cholesterol) and decreasing HDL (good cholesterol). Plus, studies that have followed women over a stretch of time have found that those women with early menopause (45 and younger) have more cardiovascular health issues later on than those who have menopause closer to the normal age (around 50).
Complex hormonal changes are taking place during menopause, particularly when menopause occurs at a younger age compared to the average menopausal age of 50 years. “We may not be exactly measuring the things that affect cardiovascular risk,” cautions Dr. Pamela Ouyang, Director of the Women’s Cardiovascular Health Center at Johns Hopkins Bayview Medical Center. “Early menopause seems to have some effect on cardiovascular health, but there is still plenty of debate as to exactly what that effect is and how much.”
Also, many cardiovascular events that are associated with menopause can also be attributed to general aging. Dr. Ouyang believes that more definitive research needs to be done to clear some of the confusion.
Hormone therapy (HRT)
During menopause, the ovaries gradually stop producing estrogen. Hormone replacement therapy (HRT) is a way to give some of the estrogen back and help regulate common menopausal symptoms such as hot flashes, as well as prevent osteoporosis. Estrogen products are commonly taken orally as a pill, applied to the skin with a cream or a patch, or taken intravaginally.
Taken alone, estrogen can increase a woman’s chance of developing endometrial cancer (cancer in the uterine lining). During a woman’s pre-menopausal and reproductive years, menstruation causes the body to shed endometrial cells. During menopause this stops happening, and introducing estrogen can cause an overgrowth of these cells.
Estrogen is often prescribed with progesterone to mitigate or reverse the growth of endometrial cells. For women who have had hysterectomies, this overgrowth of cells is not an issue, so estrogen is prescribed by itself.
What effect does hormone replacement therapy have on cardiovascular health?
Hormone replacement therapy can be useful in controlling menopausal symptoms (hot flashes, etc.) and helping to prevent osteoporosis. But there’s still debate as to its cardiovascular benefit.
The Women’s Health Initiative, a long-term National Institutes of Health-funded study tested the effects of hormone replacement therapy among postmenopausal women. Two groups of women were studied: women with an intact womb who took estrogen with progesterone or a lookalike placebo, and women who had prior hysterectomies and took estrogen only or a placebo.
Neither group showed any cardiovascular benefit from the hormone, and both groups showed a slight increase for stroke and thrombosis (blood clotting). As a result of this important study, hormone therapy is not recommended for cardiac protection after menopause. However, Dr. Ouyang says the research raises an important unresolved issue, and is an area that is still being studied:
Since a large number of research trials included women about 10 years past the age of menopause, would the results have been different if the study covered women in the midst of their menopausal years?
There are several new studies currently investigating the difference between women who receive hormone replacement closer to menopause vs. later in life.
Based on the current research, the FDA recommends that women who use hormone replacement therapy do so under close medical supervision, and only for managing menopausal symptoms such as hot flashes. Women are not advised to use hormone replacement therapy for reducing cardiovascular risk.
Menopause involves the whole body, and may call for more than a gynecologist’s care
The hormonal changes that occur during menopause can bring increased cardiovascular risk in the form of higher blood pressure and cholesterol levels. “It’s a good time to consider switching from being evaluated by a gynecologist alone to a more general internist,” suggests Dr. Ouyang.
If cardiovascular disease runs strongly in the family, it’s also important that you see a cardiologist to further assess the likelihood of having cardiovascular disease and to optimize treatment.