A new UCLA study suggests that disparities in cardiovascular disease risk in the United States are due less to race or ethnicity than to socioeconomic status.
In the study, published in the August issue of the journal Annals of Epidemiology, researchers from the David Geffen School of Medicine at UCLA and colleagues found that there are large differences in risk by socioeconomic status within racial and ethnic groups — with the poorest individuals having the highest risk — but that there are few differences in risk between racial and ethnic groups.
"Most ethnic differences in cardiovascular risk are really due to socioeconomic differences between the races in the U.S. — except for one outstanding exception," said lead researcher Dr. Arun Karlamangla, an associate professor of medicine in the division of geriatrics at the Geffen School of Medicine. "Foreign-born Mexican Americans, as opposed to Mexican Americans born here, are healthier than everyone else, and this may have less to do with ethnicity or genes than with migration patterns."
Previous studies have found large differences in health outcomes by both socioeconomic status and race and ethnicity, and these are thought to be due to differences in access to care, health behaviors, and levels of economic and social stresses, which have been linked to heart disease.
Racial disparities in health have also raised the question of whether there is a genetic component to these differences, but it has been difficult to untangle real racial and ethnic disparities from socioeconomic disparities because of the higher numbers of socioeconomically disadvantaged individuals in minority racial and ethnic groups.
Using data from 12,154 individuals in the National Health and Nutrition Examination Survey (2001-06), the study authors examined the 10-year risk for coronary heart disease — as predicted by the National Cholesterol Education Program Adult Treatment Panel III guidelines, updated in 2004 — as well as the prevalence of metabolic syndrome and overt diabetes mellitus, a major contributor to coronary heart disease risk, among various racial and ethnic groups.
To separate out socioeconomic risk differences from racial and ethnic differences, the researchers examined socioeconomic disparities separately within the racial and ethnic groups, which included non-Hispanic whites, non-Hispanic blacks, U.S.-born Mexican Americans and foreign-born Mexican Americans (those born in Mexico but living in the U.S.). They also examined racial and ethnic differences among individuals from the same socioeconomic stratum.