Women who enter natural menopause before age 40 face about a 40% higher lifetime risk of developing coronary heart disease than women who experience menopause later, according to a large Northwestern Medicine study that is the first to calculate lifetime heart risk associated with premature menopause.
The findings suggest that doctors should routinely ask women about age at menopause, using the menopausal transition as an opportunity to identify higher-risk women and intervene earlier.
"When menopause happens before age 40, women still have more than half of their life expectancy ahead of them," said study lead author Dr. Priya Freaney, assistant professor of medicine in the division of cardiology at Northwestern University Feinberg School of Medicine.
"Understanding their cumulative lifetime risk of blockage-related heart disease is critical," she said.
The study was published today (March 18) in JAMA Cardiology.
Coronary heart disease is a condition where the heart's arteries become blocked or narrowed by a buildup of fatty deposits called plaque. By restricting blood flow to the heart, these plaques can lead to sudden events (heart attacks) or gradual damage (weakened heart muscle).
The study of more than 10,000 U.S. women followed for decades also found that premature menopause was three times more common among Black women than white women (15.5% vs. 4.8%). According to Freaney, the disparity likely reflects a complex mix of life-course exposures, health conditions and structural inequities rather than solely inherent biological differences.
How the study was conducted
Freaney and colleagues analyzed data from 10,036 postmenopausal Black and white women who participated in six long-running U.S. studies, including the Framingham Heart Study, Atherosclerosis Risk in Communities Study and the Women's Health Initiative.
The women were followed between 1964 and 2018. During that time, the Northwestern scientists found more than 1,000 cases of coronary heart disease events in the data, including fatal and non-fatal heart attacks.
Even after accounting for cardiovascular risk factors such as smoking, obesity, hypertension and diabetes, premature menopause was associated with 41% higher risk of coronary heart disease for Black women and 39% increased risk for white women.
What causes premature menopause
Menopause is defined as one full year after a woman's final menstrual period. In the U.S., the average age of menopause is 51. Researchers typically define early menopause as menopause between ages 40 and 45 and premature menopause as menopause before age 40.
The scientists note in the study that the causes of premature menopause are not fully understood and are likely multifactorial. Potential contributors include genetic, biological and environmental factors, as well as earlier age of the first menstrual period, health behaviors (such as smoking), obesity and the cumulative effects of chronic stress.
It is also unclear whether the menopausal transition itself creates a vascular environment that promotes disease, or whether women who experience premature menopause already have an underlying risk profile that predisposes them to both premature menopause and cardiovascular disease.
Menopause and heart health
Even at the average age, menopause's hormonal changes can affect cardiovascular health. During menopause, declining estrogen levels trigger changes that increase coronary heart disease risk.
"As the natural estrogen declines, no matter what age it happens in, cholesterol and blood pressure go up, body fat distribution shifts to the abdomen, muscle mass gets lower, blood sugars can become dysregulated and arteries stiffen," said Freaney, who also is director of the Women's Heart Care Program at Northwestern Medicine Bluhm Cardiovascular Institute.
"Together, these changes over a short period increase the risk of heart disease."
What women and doctors should know
Freaney said women who experience premature menopause should think of it as an early signal to take their heart health seriously. "Tell yourself: I have to be far more proactive than my neighbor about my own heart health," Freaney said. "The vast majority of heart disease is preventable, but people need to know that they're at risk early in life because effective prevention takes decades."
"Tell your doctor, 'I experienced premature menopause. What can we do to protect my heart?'" she suggests.
The findings also highlight a gap in how menopause is discussed in medical care, according to Freaney. "All clinicians need to get comfortable asking about menopause because we have estrogen receptors from our head to our toes."
For years, menopause has largely been treated as a gynecologic issue, she said. But the hormonal transition affects nearly every system in the body, including the cardiovascular system. That means cardiovascular clinicians should routinely ask about menopause history when assessing long-term cardiovascular risk.
"Historically, women have been vastly understudied in cardiovascular science, and we still have much to learn about how menopause influences heart health," Freaney said.
The study is titled"Premature Menopause and Lifetime Risk of Coronary Heart Disease."
