Race Not Key to Blacks’ Heart Disease Risk, Studies Find
When it comes to dying of heart disease, where you were born and your status in society are more important than the color of your skin, researchers said Wednesday.
African Americans have long been known to be more likely than whites to die from heart disease and strokes, and many researchers have attributed the disparity to racial differences.
But environmental factors--including diet, smoking, lifestyle, poverty--are more important in determining that risk than any inherent racial differences, according to two new studies published today in the New England Journal of Medicine.
One team studied heart-disease deaths among residents of New York City and found that African Americans born in the northeastern United States were at no greater risk than whites, but were twice as likely to die from heart disease as blacks born in the Caribbean. New York blacks who were born in the South, however, were twice as likely to die of heart disease as blacks or whites born in the Northeast.
“These are huge differences, much larger than we see with blood pressure or lipids,” said Dr. Michael H. Alderman of the Albert Einstein College of Medicine, a co-author of the study. “In fact, the whole excess cardiovascular mortality [among blacks in New York City] is due to the experience of Southern-born blacks.”
Blacks who are born into the dietary and cultural patterns of the South and later move into the urban stress of New York City have “the worst of all cardiovascular worlds,” according to an editorial by Dr. Richard F. Gillum of the Centers for Disease Control and Prevention in the same journal. Researchers speculate that high-fat diets, smoking and alcohol use, among other factors, may be more common in the South.
The second study showed that African Americans living in areas of high poverty, including Harlem, Watts and central Detroit, were at much greater risk of dying from all causes than blacks living in more affluent areas.
The two studies “point out the fact that we can’t assume that all blacks are the same” in terms of cardiovascular risk, said Dr. Charles K. Francis of Harlem Hospital in New York City. “They suggest that cultural factors, diet, level of exercise and other factors may be as important as, or more important than, whether someone is black or white.”
Unfortunately, added epidemiologist Paul Sorley of the National Heart, Lung and Blood Institute, “Nobody has the data to understand why this is happening. . . . There are a lot of things we don’t understand.”
Alderman and his colleagues studied all heart attack deaths in New York City, using death certificates to identify place of birth. Cardiovascular disease was the leading cause of death for both blacks and whites.
“We did the relatively simple thing of dividing black residents of New York City into three roughly equal groups depending on where they were born, and we found tremendous differences in the likelihood of death,” especially from heart attack, Alderman said.
Overall, they found that male and female blacks born in the Caribbean and the Northeast had lower rates of death from coronary disease than did Northeastern-born whites. Only when blacks born in the South were added did blacks have a higher mortality rate from heart disease.
There were not enough New York City whites who migrated from the South to make a comparable breakdown, Alderman noted.
In the second study, Dr. Arline Geronimus and her colleagues from the University of Michigan School of Public Health studied both blacks and whites in inner-city, poverty-stricken regions and nearby areas of higher socioeconomic status. For both races, they found higher mortality rates for people in the poorest areas.
An earlier study of Harlem, conducted in 1980, had found that black men living there had less chance of surviving to age 65 than did men in Bangladesh. Geronimus’ study showed that the situation has, in fact, worsened.
Intriguingly, Francis noted, the study found that the highest mortality rate for poor whites was in Detroit, a city with a high population of Southern migrants attracted by the automobile industry. The finding suggests, he said, that the same factors that increase the death rate for Southern-born blacks in New York City are equally dangerous for Southern-born whites.
