New research identifies a link between a lesser-known hormone called anti-Müllerian hormone (AMH) and lipid or cholesterol levels in middle-aged women.
With this information and what is known about estrogen, clinicians can get a better idea of cardiovascular risk for menopausal people. Findings appear in: Journal of Clinical Lipidology.
“Estrogen isn’t the only story,” says Samar R. El Khoudary, MD, professor of epidemiology at the University of Pittsburgh School of Public Health. “We’re now getting more information about other markers that can play an important role and tell women more precisely and consistently where they are in relation to their menopausal transition.”
During the period before, during, and after the menopause, also known as the menopausal transition, middle-aged women are at increased risk for cardiovascular disease due to changes in lipid levels, such as a sharp increase in LDL-C, or “bad” cholesterol.
Scientists have previously determined that this increased risk of cardiovascular disease may be due in part to a decrease in estrogen levels. However, estrogen replacement therapy has not had the cardioprotective effects that doctors had hoped for. Therefore, scientists are investigating other factors that can affect cholesterol levels.
AMH is a hormone best studied as an important factor in determining the sex of a fetus in the womb. But recently, AMH has been found to have a strong and reliable link with the timing of the menopausal transition, and new technology is making monitoring increasingly easy and affordable.
“AMH can be used to measure how long your ovaries can continue to produce eggs,” says El Khoudary. “The more eggs there are, the higher the AMH; the fewer eggs, the lower the AMH level. When levels get too low, we can use that to predict menopause.”
Because there is such a strong link between AMH and menopause, El Khourdary wondered if the loss of AMH, like estrogen, would have an effect on cholesterol.
“We wanted to understand the mechanism behind lipid changes during the menopausal transition and how this new biomarker AMH interacts with estrogen and affects lipids,” explains El Khoudary.
El Khoudary’s team analyzed blood samples from the Nationwide Women’s Health Survey (SWAN), which followed a diverse group of 1,440 middle-aged women during the menopausal transition. These blood samples were tested for estrogen and AMH levels, as well as good and bad cholesterol.
Through this study, El Khoudary found that high estrogen level is important for lowering LDL-C or bad cholesterol levels, while high AMH is responsible for lowering HDL-C or “good” cholesterol. This means that during the menopause transition, women lose estrogen and AMH, raising both bad and good cholesterol levels.
This may sound contradictory, but it supports his suspicions that good cholesterol isn’t always good for menopausal women, according to El Khoudary. Previous research from El Khoudary’s group has determined that the good cholesterol levels in these women can mask other cardiovascular problems and may even be a sign of HDL dysfunction, by preventing good cholesterol from performing its heart-protective duties.
In the future, El Khoudary hopes to examine blood samples from middle-aged women currently on hormone replacement therapy to determine the effects of estrogen on AMH and lipid levels and to conclude whether these treatments actually help or harm menopausal women. He hopes his work can better inform both patients and doctors when making decisions for their cardiovascular health.
Other authors of the paper are from the University of Pittsburgh, Albert Einstein College of Medicine, University of Massachusetts, Stanford University and Veterans Affairs Palo Alto Health Care System, University of Alabama, Massachusetts General Hospital, and the University of Michigan.
Source: University of Pittsburgh