November 24 (HealthDay News) -- Young black American men have higher central blood pressure and stiffer blood vessels than white males, indicating that black men are developing high blood pressure at an early age and with little outward signs, according to a study by researchers at the University of Illinois, Urbana-Champaign.

The findings suggest that measuring central blood pressure (the pressure in the aorta -- the main artery leaving the heart) may be more valuable than measuring brachial blood pressure (on the arm) when assessing black men for hypertension.

"Central blood pressure holds greater prognostic value than conventional brachial blood pressure as central pressure more aptly reflects the load encountered by the heart," the researchers wrote. "Thus brachial blood pressure may neglect important information on cardiovascular burden and response to therapy in African-American men."

The study included 25 black men and 30 white men, average age 23. Both groups had similar results on a variety of measures, including heart rate, cardiorespiratory fitness, body mass index, body fat, blood lipids and glucose levels. They also had similar brachial blood pressure, but the black men had significantly higher central blood pressure.

The black males also showed early signs of vascular damage that can lead to hypertension, including stiffer arteries throughout the body and thicker carotid (neck) arteries, something that's usually found in older people and is associated with atherosclerosis.

"Although having a similar cardiovascular risk factor profile as young white men, diffuse macrovascular and microvascular dysfunction is present at a young age in apparently healthy African-American men," the researchers wrote. "Values seen are comparable to values often reported in older individuals or individuals with more advanced hypertensive disease."

The researchers didn't examine why this occurs in young, fit black men, but suggested environmental factors, such as diet, may play a role.

The study was published online in the American Journal of Physiology -- Heart and Circulatory Physiology.

SOURCE: The American Physiological Society, news release, Nov. 17, 2008