Researcher Luisa N. Borrell, assistant professor of epidemiology with Columbia University's school of public health, said her research is the first to examine hypertension along racial lines within the Hispanic ethnic group.
On the whole, U.S. Hispanics have lower rates of high blood pressure (16.8 percent) than non-Hispanics (24.7 percent), the study found.
But that apparent health advantage could be an artifact of disregarding race, the study suggests. The "protective effect" of being Hispanic does not cover black Hispanics, Borrell said.
"The idealized Hispanic health advantage disappears when race is accounted for," she said. "We are ignoring the real health profile of Hispanics."
The study is published in the February issue of the journal Ethnicity & Disease.
Borrell analyzed data collected in the National Health Interview Survey conducted by the National Center for Health Statistics. The survey asked participants if they had been told by a doctor or other health professional if they had high blood pressure, and included interviews with more than 12,000 Hispanic adults.
"Overall, blacks, regardless of their ethnicity, exhibited the highest prevalence of hypertension," the study said.
David R. Williams, a professor with the Institute of Social Research at the University of Michigan, said Borrell's research is a first step toward explaining what it is about race that affects health.
"I think we know that there is nothing inherently about being black that leads to higher rates of hypertension," Williams said. "We can't stop at the descriptive level. What is it about being black that makes the difference?"
"This kind of comparison could help tease out the effect of race as a marker for inequality in opportunities and, further, as a cause for existing health disparities," Borrell said of her work.
Williams and Borrell said they believe hypertension is driven, in part, by the particular social context in which people live.
"It's the perception of otherness that leads to discrimination and racism," Borrell said.
Both researchers explained that in America especially, people with darker skin can live in social spheres that include prejudice and disadvantaged life chances, which can translate to poorer health.