June 21, 2010

BIRMINGHAM, Ala. - University of Alabama at Birmingham (UAB) research has revealed that women who experience early menopause, regardless of race, are twice as likely to suffer from cardiovascular disease as women who experience menopause in later years.

The findings were presented the annual meeting of The Endocrine Society Saturday, June 19 in San Diego.

Melissa Wellons, M.D., a fellow in the UAB Division of Endocrinology, Diabetes and Metabolism and the study's lead author, said previous research has shown a link between early menopause and cardiovascular disease in mostly white and European populations. But this multi-ethnic study also included persons of African, Hispanic and Chinese descent.  

"Cardiovascular disease is the No. 1 killer of women," Wellons said. "More women die from heart disease and stroke than any other medical problems, and all women who live long enough will experience menopause. Early menopause - which we defined at an age younger than 46 - may be a marker of an increased risk of heart disease.

"This appeared to be the case for women of European descent, and we wanted to know if it held true for women more representative of the U.S. population, which it did," she said.

Wellons and her team looked at approximately 2,500 women from the Multi-Ethnic Study of Atherosclerosis (MESA) who had experienced menopause naturally, surgically as a result of the removal of their ovaries or who were not menopausal but still had their uterus.

MESA is an observational research study that was initiated in July 2000 to investigate the prevalence, correlates and progression of subclinical cardiovascular disease in a population-based sample of 6,500 men and women ages 45-84 years from six communities in the United States. It is funded by the National Heart Lung and Blood Institute of the National Institutes of Health. 

The team compared the women who reported they had experienced menopause at an age younger than 46 to women who had not. At the baseline examination, higher proportions of women with early menopause were smokers and had diabetes. However, blood pressure and cholesterol levels were similar between the groups at the baseline examination. Women with an early menopause were of similar age to those without early menopause.

Among the 2,509 women who formed the cohort for analysis, 693 reported menopause before age 46. A higher proportion of women with early menopause were of African and Hispanic descent, and a higher proportion of women with early menopause had undergone surgical menopause.

The main outcome the researchers examined was a combined outcome of cardiovascular disease events that included heart disease, stroke and death from these and other cardiovascular events.

"We found that among all ethnicities, women who had an early menopause were two times more likely to have a cardiovascular disease event - a heart attack, resuscitated cardiac arrest, definite angina, probable angina (if followed by revascularization), stroke, stroke death, coronary heart disease death or other atherosclerotic/CVD death - than the women who had experienced menopause after age 46," Wellons said.

Because this is an observational study, she said, they cannot conclude that early menopause somehow causes future cardiovascular disease. However, these findings do support the use of age at menopause as a marker of future heart and vascular disease risk, said Wellons, adding that clinicians should consider incorporating questions on menopause when collecting a patient's medical history.

"Because black and Hispanic women reported more incidence of early menopause, these findings may be particularly helpful and relevant to them," she said. "However, more research still is needed to better understand the underlying mechanisms behind early menopause and cardiovascular disease." 

About the UAB Division of Endocrinology, Diabetes, and Metabolism
The UAB Division of Endocrinology, Diabetes, and Metabolism has a multi-faceted mission that includes state-of-the-art clinical care for a variety of disorders of the endocrine system, clinical and basic endocrine investigation plus the education of medical students, graduate students, residents and postdoctoral fellows.