Pitt Study Questions The Role Of Homocysteine In Heart Disease

October 22, 1997

PITTSBURGH, Oct. 22 -- Previous studies have suggested that homocysteine, a by-product of dairy and meat foods, is a risk factor for heart disease. But now, evidence from a new study by University of Pittsburgh researchers counters this premise. Their work is published in the current issue of the American Heart Association's (AHA) journal, Arteriosclerosis Thrombosis and Vascular Biology.

Results from the Multiple Risk Factor Intervention Trial (MRFIT) suggest that homocysteine more likely indicates the extent of atherosclerosis or inflammation rather than promotes the processes that lead to the end points of heart disease, such as stroke or heart attack.

Pitt researchers analyzed blood samples and found no difference in homocysteine levels between men who suffered heart attacks and men who had not experienced heart attacks.

"This indicates that the role of homocysteine in heart disease might be different than previously thought," noted Rhobert W. Evans, Ph.D., assistant professor of epidemiology at Pitt's Graduate School of Public Health. "Our study clearly challenges scientists and clinicians to re-evaluate the association between homocysteine and cardiovascular disease."

Most studies that have reported a link between homocysteine and heart disease are case-control studies. That is, the researchers have recruited two groups of individuals, the control group in which no one has suffered heart disease and the case group in which every individual has heart disease. The investigators then looked at medical histories of the patients and measured homocysteine levels at the same time.

"It is possible that the associations found in these retrospective case-control studies can be attributed to elevations in homocysteine concentrations that follow a heart attack or stroke," commented Dr. Evans.

Other studies have shown that homocysteine levels may increase after a heart attack or stroke. Pitt researchers also point out that homocysteine levels have been linked with other risk factors for heart disease, which may confound the association between homocysteine and heart disease.

The MRFIT study enrolled 12,866 men between 1973 and 1976 who were healthy with no reported cases of heart disease. In this prospective study, blood samples were taken and stored and the men were monitored for up to 17 years for heart disease.

"Our study is one of a few prospective studies that has examined the relationship between homocysteine levels and heart disease risk. We have found no causal link between homocysteine levels and heart disease," stated Dr. Evans.

Dr. Evans and his colleagues discount the possibility that the homocysteine in the stored blood samples degrades after storage. They also point out that dietary fluctuations do not explain the difference between their study findings and previous results by other investigators, because the men enrolled in the MRFIT study fasted before blood was drawn.

An editorial published in the AHA journal, Circulation, by David Wilcken, M.D., of the Prince Henry Hospital, Sydney, pointed to the fact that a review of the role of homocysteine and heart disease needs to be conducted.

For additional information about the University of Pittsburgh Graduate School of Public Health, please access http://www.pitt.edu/~gsphhome/.

University of Pittsburgh Medical Center

Related Heart Disease Articles from Brightsurf:

Cellular pathway of genetic heart disease similar to neurodegenerative disease
Research on a genetic heart disease has uncovered a new and unexpected mechanism for heart failure.

Mechanism linking gum disease to heart disease, other inflammatory conditions discovered
The link between periodontal (gum) disease and other inflammatory conditions such as heart disease and diabetes has long been established, but the mechanism behind that association has, until now, remained a mystery.

New 'atlas' of human heart cells first step toward precision treatments for heart disease
Scientists have for the first time documented all of the different cell types and genes expressed in the healthy human heart, in research published in the journal Nature.

With a heavy heart: How men and women develop heart disease differently
A new study by researchers from McGill University has uncovered that minerals causing aortic heart valve blockage in men and women are different, a discovery that could change how heart disease is diagnosed and treated.

Heart-healthy diets are naturally low in dietary cholesterol and can help to reduce the risk of heart disease and stroke
Eating a heart-healthy dietary pattern rich in vegetables, fruits, whole grains, low-fat dairy products, poultry, fish, legumes, vegetable oils and nuts, which is also limits salt, red and processed meats, refined-carbohydrates and added sugars, is relatively low in dietary cholesterol and supports healthy levels of artery-clogging LDL cholesterol.

Pacemakers can improve heart function in patients with chemotherapy-induced heart disease
Research has shown that treating chemotherapy-induced cardiomyopathy with commercially available cardiac resynchronization therapy (CRT) delivered through a surgically implanted defibrillator or pacemaker can significantly improve patient outcomes.

Arsenic in drinking water may change heart structure raising risk of heart disease
Drinking water that is contaminated with arsenic may lead to thickening of the heart's main pumping chamber in young adults, according to a new study by researchers at Columbia University Mailman School of Public Health.

New health calculator can help predict heart disease risk, estimate heart age
A new online health calculator can help people determine their risk of heart disease, as well as their heart age, accounting for sociodemographic factors such as ethnicity, sense of belonging and education, as well as health status and lifestyle behaviors.

Wide variation in rate of death between VA hospitals for patients with heart disease, heart failure
Death rates for veterans with ischemic heart disease and chronic heart failure varied widely across the Veterans Affairs (VA) health care system from 2010 to 2014, which could suggest differences in the quality of cardiovascular health care provided by VA medical centers.

Heart failure: The Alzheimer's disease of the heart?
Similar to how protein clumps build up in the brain in people with some neurodegenerative diseases such as Alzheimer's and Parkinson's diseases, protein clumps appear to accumulate in the diseased hearts of mice and people with heart failure, according to a team led by Johns Hopkins University researchers.

Read More: Heart Disease News and Heart Disease Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.