African-Africans May Develop High Blood Pressure Faster

Sept. 14, 2011-- African-Americans may develop high blood pressure faster than whites with the same risk factors, according to a new study.

Researchers found that African-Americans with prehypertension progressed to hypertension a year sooner than whites with the same condition.

African-Americans with prehypertension were also more likely than whites to develop hypertension.

"The fact that African-Americans progress faster to hypertension has a direct link to the higher prevalence of hypertension and its complications, such as stroke and kidney disease, in blacks than whites," study researcher Anbesaw Selassie, DrPH, says in a news release. Selassie is an epidemiologist at the Medical University of South Carolina in Charleston.

The study is published in Hypertension: Journal of the American Heart Association.

Prehypertension is a major risk factor for hypertension. It's defined as having a systolic blood pressure (top number) of 120 to 139 mm Hg or a diastolic blood pressure (bottom number) of 80 to 89 mm Hg.

Hypertension or high blood pressure is systolic blood pressure of 140 mm Hg or higher or a diastolic blood pressure of 90 mm Hg or more.

Previous studies have already shown that hypertension, heart disease, and stroke are more common in African-Americans than in whites.

Moving From Prehypertension to Hypertension

In the study, researchers used electronic medical records to analyze the risk of progressing from prehypertension to hypertension among 18,865 adults aged 18 to 85.

The results showed that African-Americans progressed from prehypertension to hypertension an average of a year faster than whites.

Other risk factors associated with a faster conversion to high blood pressure were:

• Having a systolic of 130-139 mm Hg
• Older age (75 years and over)
• Being overweight or obese
• Having type 2 diabetes

The study also showed that African-Americans with prehypertension were 35% more likely than whites to develop hypertension.

More Aggressive Treatment Needed?

Current treatment guidelines do not recommend medication to lower blood pressure for people with prehypertension.

Most people with prehypertension are advised to make healthy lifestyle changes, such as losing weight, limiting salt intake, and eating a healthy diet rich in fruits and vegetables, to reduce their risk of developing hypertension.

But researchers say the results of this study suggest more aggressive treatment of prehypertension in African-Americans is needed.

"I firmly believe that without early therapeutic interventions such as medication, we cannot narrow the gap between blacks and whites on these outcomes," says Selassie.

Experts say the study highlights the need for further study into why African-Americans are more prone to hypertension and its related complications.

"Ultimately, tangible and fundamental answers must be forthcoming in order to explain why the black population develops hypertension more frequently and rapidly," Edward D. Frohlich, MD, of the Ochsner Clinic Foundation in New Orleans, writes in an accompanying editorial.