News Release

University of Pittsburgh study finds that simple test spots early signs of heart disease in women

Peer-Reviewed Publication

University of Pittsburgh Medical Center

PITTSBURGH, Aug. 27 -- Women may now have a powerful new weapon in the war against heart disease. A study by researchers at the University of Pittsburgh has shown that a non-invasive test called electron beam computed tomography (EBCT) can predict heart problems in middle-aged women who lack any clinical signs of disease and who have no standard risk factors.

The study, published in the September 1999 issue of Arteriosclerosis, Thrombosis and Vascular Biology, suggests that more women should receive the test regardless of their perceived risk of heart disease.

"Heart disease is the number one killer of women, but it doesn't happen overnight," said Lewis Kuller, M.D., Dr. P.H., the principal investigator who is also a university professor and the chairman of the department of epidemiology at the University of Pittsburgh's Graduate School of Public Health. "With this technology, we can now find arterial problems much earlier in women so that they can take the necessary steps to avoid life-threatening complications later on."

These published findings extend results of a presentation made last fall at the American Heart Association's annual meeting in Dallas.

The 15-year study is the first to evaluate the relationship of heart disease risk factors measured before menopause and the extent of early, or subclinical, disease in the coronary arteries and aorta as measured after menopause using EBCT, also known as ultrafast CT. EBCT involves rapidly scanning the beating heart or aorta with X-rays to accurately detect the presence of calcification. Calcium in these arteries indicates the presence of atherosclerosis and can be present long before obstructions occur.

"While the EBCT predictably showed that premenopausal women with high risk factors developed calcification after menopause, we were surprised to find that the test also showed the same subclinical disease in some women who had no risk factors premenopausally," said Dr. Kuller. "This means that we now have a powerful tool to help more women ward off life-threatening illness."

Scientists have long known that women's chances of developing heart disease rise sharply as they pass through menopause, a time of complex hormonal and physiological changes. Equally well known are the risk factors: obesity, smoking, high levels of LDLc (bad) cholesterol, low levels of HDLc (good) cholesterol and high triglycerides. But until now, no analysis had been done combining these factors with results from new tests that detect subtle signs of atherosclerosis. These early indications of the disease are not picked up through conventional means like stress tests or angiography.

"EBCT is an underutilized tool which provides an accurate picture of subclinical atherosclerosis in the coronary arteries and aorta of postmenopausal women," said Daniel Edmundowicz, M.D., assistant professor of medicine and director of the Preventive Heart Care Center at the University of Pittsburgh Medical Center's Cardiovascular Institute. "This study demonstrates that EBCT can be effectively applied in a preventive setting to aid in the management of heart disease."

The University of Pittsburgh project involved 541 premenopausal women, with an average age of 48, who participated in the Healthy Women Study, begun in 1983-84, to look at changes in biological and behavioral characteristics as they went from premenopause to postmenopause. Among the baseline measurements taken were caloric intake and fat as a percentage of total calories, blood samples, blood pressure, levels of total cholesterol, LDLc, HDLc, triglycerides and physical activity.

After an average of 11 years, 168 of the women later underwent an EBCT of the heart and aorta to measure calcification. A total of 91 percent of the participants were white, 50 percent had a college education or higher and 28 percent were on hormone replacement therapy (HRT), with 79 percent of those women on estrogen and progesterone. Among the findings in the study:

  • High LDLc levels were a powerful predictor of the extent of coronary and aortic calcification.
  • Conversely, high HDLc levels resulted in practical immunity to developing significant coronary or aortic coronary calcification.
  • In combination with high LDLc levels, cigarette smoking among women was a powerful predictor of aortic and coronary calcification.
  • Women with high LDLc levels and a low HDLc were at high risk of having high calcium scores, 38 percent, versus only 4 percent for those with low LDLc and high HDLc.
  • Among smokers with a high LDLc and a low HDLc, 86 percent had evidence of coronary calcification compared to only 17 percent of women who were nonsmokers with a low LDLc and a high HDLc.

This study was supported by grants from the National Institutes of Health.

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For more information about the GSPH's department of epidemiology, please access http://www.pitt.edu/~epidept/epihome.html . For information on cardiovascular services, access UPMC's Cardiovascular Institute at http://www.upmc.edu/cardiology/ .


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