Nav: Home

Aorta more rigid in African-Americans, may explain rates of hypertension and heart disease

November 09, 2016

DALLAS - Nov. 9, 2016 - African-Americans have more rigidity of the aorta, the major artery supplying oxygen-rich blood to the body, than Caucasians and Hispanics, according to a study by UT Southwestern Medical Center cardiologists.

The finding is important because African-Americans are the group at greatest risk of high blood pressure and organ damage caused by high blood pressure, and aortic rigidity is associated with high blood pressure.

The study examined data from some 2,500 participants in the Dallas Heart Study, a multi-ethnic population-based cohort. The researchers used two methods to assess stiffness of the aorta, which is the largest artery in the body, running from the top of the left ventricle in the heart down to the abdomen. Both systems of measurement found greater stiffness in the aortas of African-Americans.

"Our demonstration of ethnic differences in arterial stiffness is an important step in understanding the mechanisms that mediate ethnic differences in cardiovascular disease," said Dr. Wanpen Vongpatanasin, Professor of Internal Medicine at UT Southwestern Medical Center, and co-senior author of the study, which appears online in the Journal of the American College of Cardiology: Cardiovascular Imaging.

Hispanics in the study had an intermediate level of aortic stiffness, greater than Caucasians, but less than that of African-Americans.

The study found that both African-Americans and Hispanics had smaller diameter aortas, after adjustments were made for weight.

"This finding suggests that there may be a mismatch between aortic diameter and adiposity, which contributes to the increased rigidity," said Dr. Vongpatanasin, who holds the Norman and Audrey Kaplan Chair in Hypertension and the Fredric L. Coe Professorship in Nephrolithiasis in Mineral Metabolism.

Other possible mechanisms underlying the increased levels of aortic stiffness in African-Americans and Hispanics include greater sodium intake among African-Americans and Hispanics, lower intake of potassium, and genetic differences in collagen content. Collagen is a protein fiber that is a key component of connective tissue such as bone and artery walls.

According to figures from the Centers for Disease Control and Prevention, 43 percent of African-American men and 45.7 percent of African-American women have hypertension, or high blood pressure, compared with 33.9 percent of Caucasian men and 31.3 percent of Caucasian women.

"Hypertension is strongly associated with heart attack and stroke. Our study provides a potential explanation for excess risk of hypertension and resultant organ complication in African-Americans, who are at particularly high risk of cardiovascular disease," said Dr. Vongpatanasin.

The Dallas Heart Study is an ongoing, multi-ethnic epidemiologic study, funded by the Donald W. Reynolds Foundation. More than 6,000 individuals in Dallas County have participated in the study, which has led to more than 200 published papers and key findings about heart disease, cholesterol, and liver disease.
-end-
Other UT Southwestern researchers who contributed to this study are Dr. Christopher Maroules, Assistant Instructor; Colby Ayers, Faculty Associate; Dr. Roderick McColl, Associate Professor; Dr. Ronald Peshock, Professor of Radiology and Internal Medicine; and Dr. Akshay Goel, former UT Southwestern fellow.

This works was supported by a grant from the Doris Duke Charitable Foundation, National Center for Advancing Translational Sciences, National Institutes of Health, and from UT Southwestern's George M. O'Brien Kidney Research Core Center. Aortic rigidity
  • The aorta is a large, candy cane-shaped artery extending upward from the top, left chamber of the heart then curving down and running in front of the backbone to the abdomen. It is the main pipeline for the flow of blood from the heart to the rest of the body.

  • When the aorta is stiffer, or less "compliant," the large blood vessel cannot expand and rebound well as the heart contracts and relaxes, which means the heart has to work harder to pump blood throughout the body.
  • Aortic stiffness is associated with cardiovascular disease, including heart attack, stroke, and heart failure, which is the inability of the heart to pump sufficient blood to supply oxygen to the body.


SOURCE: National Institutes of Health

About UT Southwestern Medical Center

UT Southwestern, one of the premier academic medical centers in the nation, integrates pioneering biomedical research with exceptional clinical care and education. The institution's faculty includes many distinguished members, including six who have been awarded Nobel Prizes since 1985. The faculty of almost 2,800 is responsible for groundbreaking medical advances and is committed to translating science-driven research quickly to new clinical treatments. UT Southwestern physicians provide medical care in about 80 specialties to more than 100,000 hospitalized patients and oversee approximately 2.2 million outpatient visits a year.

UT Southwestern Medical Center

Related Heart Disease Articles:

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.
Women once considered low risk for heart disease show evidence of previous heart attack scars
Women who complain about chest pain often are reassured by their doctors that there is no reason to worry because their angiograms show that the women don't have blockages in the major heart arteries, a primary cause of heart attacks in men.
Where you live could determine risk of heart attack, stroke or dying of heart disease
People living in parts of Ontario with better access to preventive health care had lower rates of cardiac events compared to residents of regions with less access, found a new study published in CMAJ (Canadian Medical Association Journal).
Older adults with heart disease can become more independent and heart healthy with physical activity
Improving physical function among older adults with heart disease helps heart health and even the oldest have a better quality of life and greater independence.
Dietary factors associated with substantial proportion of deaths from heart disease, stroke, and disease
Nearly half of all deaths due to heart disease, stroke, and type 2 diabetes in the US in 2012 were associated with suboptimal consumption of certain dietary factors, according to a study appearing in the March 7 issue of JAMA.
Certain heart fat associated with higher risk of heart disease in postmenopausal women
For the first time, researchers have pinpointed a type of heart fat, linked it to a risk factor for heart disease and shown that menopausal status and estrogen levels are critical modifying factors of its associated risk in women.
Maternal chronic disease linked to higher rates of congenital heart disease in babies
Pregnant women with congenital heart defects or type 2 diabetes have a higher risk of giving birth to babies with severe congenital heart disease and should be monitored closely in the prenatal period, according to a study published in CMAJ.
More Heart Disease News and Heart Disease Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Rethinking Anger
Anger is universal and complex: it can be quiet, festering, justified, vengeful, and destructive. This hour, TED speakers explore the many sides of anger, why we need it, and who's allowed to feel it. Guests include psychologists Ryan Martin and Russell Kolts, writer Soraya Chemaly, former talk radio host Lisa Fritsch, and business professor Dan Moshavi.
Now Playing: Science for the People

#538 Nobels and Astrophysics
This week we start with this year's physics Nobel Prize awarded to Jim Peebles, Michel Mayor, and Didier Queloz and finish with a discussion of the Nobel Prizes as a way to award and highlight important science. Are they still relevant? When science breakthroughs are built on the backs of hundreds -- and sometimes thousands -- of people's hard work, how do you pick just three to highlight? Join host Rachelle Saunders and astrophysicist, author, and science communicator Ethan Siegel for their chat about astrophysics and Nobel Prizes.