SAN FRANCISCO – A new study by researchers at the University of California, San Francisco, indicates that postmenopausal women who reached menopause at an earlier age or who never gave birth may be at higher risk for heart disease.
Published online in Journal of the American College of Cardiology (JACC), the study of more than 28,000 women without heart disease over an average of 13.1 years suggests that for every additional year at which a woman entered menopause, the risk of heart failure decreased by about 1 percent.
In addition, while only 5.2 percent of the women were hospitalized for heart failure during the study, those who never gave birth were 2.75 times more likely to develop diastolic heart failure.
In the study, senior author Nisha Parikh, assistant professor of cardiology at UCSF, and her colleagues examined possible associations among total number of live births, age at first pregnancy lasting at least six months and total reproductive duration from first menstruation to menopause with incidents of heart failure.
They used data from postmenopausal women in the Women’s Health Initiative (WHI), an observational study and clinical trial of nearly 162,000 women in the United States from 1993-1998. A subset of 28,516 participants without cardiovascular disease was studied from enrollment through September 2014. The average screening age was 62.7 years, average first menstruation and menopause was 12.6 and 47.1 years, respectively, and average live births was 3.3.
The researchers found that short total reproductive duration was tied to an increased risk of heart failure, which also was found to be related to an earlier age at menopause and more pronounced in women experiencing natural, rather than surgical, menopause. Women who never gave birth were at an increased risk for diastolic heart failure, but this relationship was not due to infertility.
“By investigating the particular factors that affect women’s risk of developing heart disease, we hope to help all health care providers who take care of women better understand how to assess their patient’s risk of cardiovascular disease and to provide counseling and risk factor modification,” lead author Philip Hall, cardiology fellow at UCSF, was quoted as saying in a news release.
Noting that why this occurs is unclear, the researchers said more research is needed to determine possible mechanisms that link endogenous sex hormone exposure during a woman’s reproductive years to heart disease after menopause. “We suspect that factors leading to later menopause aside from estrogen, which is higher in women before menopause, may help protect women from developing heart failure,” said Parikh. “There also are many reasons why women might not ever give birth, but are there identifiable reasons that explain why never giving birth is associated with heart failure?
We believe future studies could lend insight into these areas.” (Xinhua)
