Women should be made aware that their cardiovascular health is likely to worsen as they go through menopause, according to researchers of the largest and longest running study of women's health in midlife.

Analysis from the Study of Women's Health Across the Nation (SWAN) found that black women experience this accelerated decline earlier in menopause than their white counterparts.

The study, led by scientists at the University of Pittsburgh Graduate School of Public Health, will be published in the March issue of Arteriosclerosis, Thrombosis, and Vascular Biology, a journal of the American Heart Association. It add to growing evidence that menopause is a critical time for changes in cardiovascular health.

Senior author Samar R. El Khoudary, associate professor of epidemiology at Pitt Public Health, said: "Midlife is not just a period where women have hot flashes and experience other menopausal symptoms. It's a time when their cardiovascular disease risk is increasing as we see significant changes in multiple clinical measures of their physical health."

Arterial stiffness changes as women transition through menopause

El Khoudary and her team used a subset of data from SWAN Heart, an ancillary study that enrolled women from Pittsburgh and Chicago between 2001 and 2003 and included two examinations of early markers of cardiovascular health over time. Ultimately, 339 women were included in this study, 36% black and the rest white.

The study focused on how arterial stiffness changes as women transition through menopause. Arterial stiffness refers to the elasticity of arteries and is measured by looking at how fast blood flows through arteries. Stiffer arteries can lead to dysfunction in how well the heart pumps and moves blood, and damage to the heart, kidneys and other organs.

The researchers tracked the women through SWAN for up to 12.5 years, or until they reached menopause, allowing them to confidently anchor the arterial stiffness measure to the menopausal transition.

On average, as women went through menopause, their arterial stiffness increased by about 0.9% up to one year before their last menstrual period to about 7.5% within one year before and after their last period, a considerable acceleration.

The black women in the study experienced greater increases in arterial stiffness earlier in the transition than white women, more than a year before menopause. The findings held after adjusting for numerous factors that could affect heart health, including waist circumference, blood pressure, lipids, smoking status, physical activity levels and financial stress.

This study follows several others that link the menopausal transition to the accumulation of heart fat, changes in cholesterol, inflammation and coronary artery calcification, among other heart disease risk factors.

"Our study is not able to tell us why we're seeing these changes during the menopausal transition," El Khoudary said. "But we speculate that the dramatic hormonal changes accompanying menopause might play a role by increasing inflammation and affecting vascular fat deposition, a hypothesis that we would like to test in future studies."