Featured Research

from universities, journals, and other organizations

High hormone levels put young black males at risk for cardiovascular disease

Date:
December 7, 2012
Source:
Georgia Health Sciences University
Summary:
Increased levels of the hormone aldosterone in young black males correlate with an unhealthy chain of events that starts with retaining too much salt and results in an enlarged heart muscle, researchers say. The findings indicate physicians may want to reach for aldosterone inhibitors early in their effort to control blood pressure and reduce cardiovascular risk in young black males.

Increased levels of the hormone aldosterone in young black males correlate with an unhealthy chain of events that starts with retaining too much salt and results in an enlarged heart muscle, researchers say.

The findings indicate physicians may want to reach for aldosterone inhibitors early in their effort to control blood pressure and reduce cardiovascular risk in young black males.

Their studies of a cohort of 191 healthy black and white 15- to 19-year-olds showed that only in the black males was higher aldosterone associated with impaired sodium excretion, increased blood pressure and enlargement of the left pumping chamber of the heart, said Dr. Gregory A. Harshfield, hypertension researcher at the Medical College of Georgia and Institute of Public and Preventive Health at Georgia Health Sciences University.

"It's a clear pathway and is consistent with the idea that is the highest risk group for developing earlier and more severe cases of hypertension," Harshfield said. Increased sodium makes the body hold onto more fluid, which increases blood pressure. Unhealthy enlargement of the pumping chamber of the heart, called left ventricular hypertrophy, results from the heart having to work too hard against high blood pressures to push blood and oxygen out to the body. Harshfield's studies have shown that black males particularly have a problem with blood pressure returning to normal following stress because of an impaired ability to eliminate sodium.

"It might be a good idea to consider early on drugs that target aldosterone in these individuals," said Diana G. Murro, a fourth-year student at MCG and first author of the study in the journal Pediatric Nephrology. While aldosterone inhibitors are used to treat refractory hypertension, they typically are not used in blacks, possibly because they haven't been well studied in that population, Harshfield said.

The steroid hormone aldosterone, produced by the adrenal gland, is part of a renin-angiotensin-aldosterone system that helps the body regulate blood pressure and sodium retention. Aldosterone acts on the kidneys, prompting them to hold onto sodium which increases blood pressure. While that can be an asset in some finite scenarios, such as having limited access to water over an extended period, it can become a major health liability in the everyday world where you can consume a day's sodium requirement in single pack of crackers, Murro said.

Each of the other subgroups of young, healthy individuals actually showed some negative impact from higher aldosterone. In white and black females, it correlated with higher baseline blood pressures. In fact, white females had the highest aldosterone levels. In white males, it correlated with reduced sodium excretion. "It was more like we had a piece of the puzzle but not the whole puzzle like we did in the black males," Murro said.

Still, all the findings were concerning, Harshfield said. "This is a normal, healthy group of young people and we are already seeing these associations."

Interestingly, only 16 of the study participants were obese, and there was no significant correlation between obesity -- a major contributor to hypertension and heart disease -- and higher aldosterone.

Similar studies are needed in hypertensive youth or those with a family history of high blood pressure to see if their findings hold, the researchers said. One of the newer, more selective aldosterone blockers, eplerenone, has proven more effective than the angiotensin II receptor blocker losartan at treating hypertension in a predominantly black, adult male population. While angiotensin is a precursor for aldosterone, at least one study indicates it's not very effective at directly suppressing aldosterone.

Fewer than half of hypertensive Americans have their blood pressure under control, according to the Centers for Disease Control and Prevention. The MCG research was funded by the National Institutes of Health. Murro worked with Harshfield as a member of the inaugural GHSU Child Health Discovery Institute Summer Scholars Program.


Story Source:

The above story is based on materials provided by Georgia Health Sciences University. The original article was written by Toni Baker. Note: Materials may be edited for content and length.


Journal Reference:

  1. Diana G. Murro, Melinda Beavers, Gregory A. Harshfield, Gaston K. Kapuku. Aldosterone contributes to elevated left ventricular mass in black boys. Pediatric Nephrology, 2012; DOI: 10.1007/s00467-012-2367-6

Cite This Page:

Georgia Health Sciences University. "High hormone levels put young black males at risk for cardiovascular disease." ScienceDaily. ScienceDaily, 7 December 2012. <www.sciencedaily.com/releases/2012/12/121207133238.htm>.
Georgia Health Sciences University. (2012, December 7). High hormone levels put young black males at risk for cardiovascular disease. ScienceDaily. Retrieved April 19, 2014 from www.sciencedaily.com/releases/2012/12/121207133238.htm
Georgia Health Sciences University. "High hormone levels put young black males at risk for cardiovascular disease." ScienceDaily. www.sciencedaily.com/releases/2012/12/121207133238.htm (accessed April 19, 2014).

Share This



More Health & Medicine News

Saturday, April 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

'Holy Grail' Of Weight Loss? New Find Could Be It

'Holy Grail' Of Weight Loss? New Find Could Be It

Newsy (Apr. 18, 2014) In a potential breakthrough for future obesity treatments, scientists have used MRI scans to pinpoint brown fat in a living adult for the first time. Video provided by Newsy
Powered by NewsLook.com
Little Progress Made In Fighting Food Poisoning, CDC Says

Little Progress Made In Fighting Food Poisoning, CDC Says

Newsy (Apr. 18, 2014) A new report shows rates of two foodborne infections increased in the U.S. in recent years, while salmonella actually dropped 9 percent. Video provided by Newsy
Powered by NewsLook.com
Scientists Create Stem Cells From Adult Skin Cells

Scientists Create Stem Cells From Adult Skin Cells

Newsy (Apr. 17, 2014) The breakthrough could mean a cure for some serious diseases and even the possibility of human cloning, but it's all still a way off. Video provided by Newsy
Powered by NewsLook.com
Obama: 8 Million Healthcare Signups

Obama: 8 Million Healthcare Signups

AP (Apr. 17, 2014) President Barack Obama gave a briefing Thursday announcing 8 million people have signed up under the Affordable Care Act. He blasted continued Republican efforts to repeal the law. (April 17) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins