Four in 10 African-Americans have cardiovascular disease, including high blood pressure, stroke, heart disease, congestive heart failure, hardening of the arteries and other ailments. Heart disease is the leading cause of death for African-Americans, accounting for 37 percent of deaths annually.

Other statistics:

In 1999, for every 100,000 Americans, 354 people of all ethnicities died of heart disease. Among African-Americans only, the rate was much higher: 526 for males and 402 for females per 100,000 population.

Compared to whites, African-Americans are much more likely to have high blood pressure and diabetes and be overweight or obese and are less likely to exercise. All of these increase risk.

In 1999, death rates from coronary heart disease, which includes heart attack, were 273 for African-American men and 193 for African-American women, compared to 196 per 100,000 for the total population.

There are many reasons why African-Americans are more vulnerable, says Dr. Stephen Liggett, a cardiologist and researcher at the University of Cincinnati.

"There are some medications that blacks don't respond to," he says, including some beta blockers.

Minorities also tend to have less access to medical care, both for basic screenings, treatment and adjustment of medication dosages, Dr. Liggett says. Less access also means less treatment for risk factors such as high blood pressure, high cholesterol and diabetes, all of which occur more often in African-Americans.

Dr. Liggett was one of the authors of a study that showed African-Americans are genetically more vulnerable to heart failure, a weakening of the heart's ability to pump blood.

The study, published in the Oct. 10 issue of the New England Journal of Medicine, showed that as many as 5 percent of African-Americans might have two flawed protein receptors.

One of the flawed receptors fails to prevent nerve cells in the heart from overproducing norepinephrine, the chemical that triggers heart contractions. The second makes heart muscle cells hypersensitive to norepinephrine.

If larger studies bear out UC's results, genetic testing could help identify candidates at increased risk for heart failure so they could be targeted for more intensive treatment, Dr. Liggett says.

- Peggy O'Farrell