http://www.miami.com/mld/miamiherald/news/15625303.htm

Posted on Thu, Sep. 28, 2006


MEDICAL RESEARCH
Do Hispanics have health edge?
A study at the University of Miami and elsewhere will explore why Hispanics live longer than other groups.
BY JACOB GOLDSTEIN
jgoldstein@MiamiHerald.com



Puzzled researchers call it the ''Hispanic Paradox'': On average, U.S. Hispanics lead longer lives than non-Hispanics, despite having less access to healthcare and higher rates of poverty.

Now, one of the most ambitious health studies of Hispanics in America may help untangle the paradox.

The federally funded six-year project -- which will begin next month and include a $10 million South Florida component -- will follow 16,000 Hispanics and include not only those of Mexican descent (the main source of health data on U.S. Hispanics) but thousands of Cubans, Puerto Ricans and Central and South Americans.

Among the questions that may be illuminated by the study: Is the paradox real, or the result of bad data? If it is real, why does it exist, and how does it vary among Hispanics? And, beyond the paradox, does it make sense to consider all Hispanics as a single group?

''The usual comparison is Hispanics versus,'' said Dr. Neil Schneiderman, the University of Miami researcher who will run the study's South Florida site. ``We lump them together. Whether we should be or not is really an open question.''

''Hispanic'' is a geographic designation, not a racial one -- it indicates only Latin American or Spanish roots.

Florida's Hispanic population -- predominantly Caribbean, Central and South American in origin, and less than 20 percent Mexican -- bears little resemblance to the national Hispanic population, in which Mexicans and Mexican Americans comprise 60 percent.

Yet on several measures, outcomes for Hispanics in Florida parallel national figures.

In Florida and nationwide, Hispanics have a lower overall cancer rate than non-Hispanics, but higher rates of liver, stomach and cervical cancer. Infant mortality is also consistent, with Hispanics showing rates below the overall average both in Florida and nationally.

DEATH RATE

Perhaps the most striking figure is the death rate. Adjusted for the average age of the population (so that a younger population does not lead to a lower rate), Hispanics in Florida have a 20 percent lower death rate than white non-Hispanics; nationally, Hispanics have a 22 percent lower death rate than white non-Hispanics.

''In the U.S., Latinos tend to be more similar than different,'' said Dr. Eliseo Perez-Stable, who was born in Cuba, lived in Miami, and now studies Hispanic health at the University of California, San Francisco. ``In general, Latinos are healthier. There is no evidence that Cubans are different in that regard.''

OTHER REASONS

This is not to say that Hispanics fare better on all health measures. In Florida and nationwide, rates of HIV, diabetes and obesity are higher among Hispanics than among non-Hispanic whites.

Yet those disparities only make the lower death rate among Hispanics more puzzling. Several theories have been proposed to explain the lower rate, and many experts think a combination of factors is at work.

• Only 15 percent of U.S. Hispanics smoke, compared with more than 20 percent of non-Hispanics.

• The ''healthy-immigrant effect'' holds that healthier people are more likely to have physical and emotional energy required to move to a foreign country; the sick and the weak don't have the wherewithal.

The idea is popular among experts, and Perez-Stable called it ''well described in anthropology.'' But it is difficult to quantify and so impossible to know how much it contributes to overall trends.

• Some researchers have argued that mortality data do not reflect the true death rate for Hispanics.

The death rate is calculated by dividing the number of deaths by the overall population. Overall population comes from the census, where people report their own Hispanic status. But number of deaths is ascertained from death certificates, usually filled out by a physician or mortician -- who sometimes fail to note Hispanic status, said Alberto Palloni, a University of Wisconsin demographer who recently studied the possible causes of the paradox.

GOING DEEPER

Palloni, following previous studies, concluded that this phenomenon probably accounts for some -- but not all -- of the paradox.

• Some immigrants return to their home countries to die and are not counted in U.S. figures. Again, Palloni said, this phenomenon seems to drive some of the disparity, and is particularly common among Mexican immigrants in the Southwest.

But after reviewing all of the popular hypotheses, Palloni concluded that ``there must be something else here.''

That something, many researchers believe, may be cultural norms such as social networks, family support and an amorphous quality called simpatia.

''There is a tendency among Latino cultures . . . of being more expressive, touching, saying hello to people, checking in in an informal way wen you see them at work or on the street,'' Perez-Stable said. ``That is not necessarily the norm in U.S. culture. In the Latino culture it's almost a transgression if you don't do that.''

Norms such as these are difficult to quantify, and even harder to relate to health outcomes. But the study launching next month, which will be funded by the National Institutes of Health, may help.

RANGE OF FACTORS

Researchers at four sites around the country -- Miami and three others to be announced -- will study not only diseases and risk factors, but also family relationships, cultural values and levels of assimilation.

That will elucidate similarities and differences between Hispanics of different origins -- and may connect social factors to health outcomes, says Elizabeth Arias, of the CDC's National Center for Health Statistics, who is not associated with the study.

''The detail of health information and socioeconomic and demographic and behavioral information that will be gathered will be tremendous,'' Arias said.

``That should . . . really answer a lot of these questions that we've been having such a difficult time answering.''