News at UI Health

Cardiovascular disease is the leading cause of death among Latinos in the U.S., and a new multicenter study of more than 16,000 Hispanic/Latino men and women ages 18 to 74-the Hispanic Community Health Study/Study of Latinos (HCHS/SOL)-shows that a large majority of Latinos have adverse levels of at least one major cardiovascular risk factor.

Those risks vary significantly among Mexicans, Puerto Ricans and Latinos of other Hispanic backgrounds, and also between Latino immigrants who arrived more recently compared with those who have lived in the U.S. for a longer period, according to the study, published in the Nov. 7 issue of the Journal of the American Medical Association.

"The study's most alarming finding was that 80 percent of Hispanic men and 71 percent of Hispanic women had at least one major cardiovascular risk factor," says Martha L. Daviglus, MD, PhD, the lead author of the study who joined the University of Illinois at Chicago as associate vice chancellor for research, director of the Institute for Minority Health Research and professor of medicine in June 2012. "This was very surprising," she says. "We were aware that this population was at high risk, but we didn't know that the proportion at risk would be so high."

HCHS/SOL showed that 28 percent of men had at least two adverse risk factors, and 21 percent had three or more; among women, 23 percent had at least two, and 17 percent had three or more adverse risk factors. Risk factors were defined using national guidelines for high cholesterol, hypertension, obesity, diabetes and smoking. Study participants were recruited in field centers located in Chicago, San Diego, the Bronx and Miami. The study was sponsored by the National Heart, Lung and Blood Institute and six other institutes, centers and offices of the National Institutes of Health.

Among the various Hispanic background groups included, the presence of three or more adverse risk factors was most common among Puerto Rican men and least common among South American women. Daviglus believes that the high prevalence of obesity and cigarette smoking among Puerto Rican men and women and high cholesterol levels among Central American men and Puerto Rican women are some of the most salient Hispanic background-specific facts that she and her fellow researchers uncovered when it comes to health care and preventive strategies.

DIVERSITY AMONG LATINOS

Previous studies typically combined Hispanic/Latino individuals into one category, Daviglus says, and have reported high prevalence of obesity and diabetes in this population-but that's a lot more valid for Puerto Ricans, for example, than South Americans. "They shouldn't be considered as a single homogenous group with regards to health care needs and disease burden," she says. "They represent different cultures and exposures depending on the country of origin. They have different levels of education. Not all Hispanic groups have a high prevalence of diabetes and obesity."

"The study highlights the heterogeneity that exists within the group of individuals that are known as Latinos," says Joe G.N. "Skip" Garcia, MD, vice president for health affairs at the University of Illinois Hospital & Health Sciences System. "People have been grouping Latinos together for the purpose of defining health disparities and genetic susceptibilities for years."

But in the "post-human-genome era," that way of thinking has become increasingly dated, Garcia says. "Being able to compare the genetic sequence of different populations, it's clear that Latinos from Mexico are pretty different from Hispanics from Puerto Rico. The mixtures of DNA are different. We need to start thinking about how to individualize therapies for Hispanic/Latino populations in a much more specific way than we've been currently doing."

Multiple risk factors were also more common among less-educated Latinos. There is also a negative impact in those considered to be more acculturated compared with those who are less acculturated to U.S. society; that is, those who have lived in the U.S. for a longer period of time and have adopted American diets and lifestyles have a higher risk factor burden, says Daviglus, who conducted the study with Gregory A. Talavera, MD, MPH, of San Diego State University, and other colleagues.

"The study confirmed that with an increasing level of acculturation, Latinos have a higher prevalence of risk factors," she says. "Hispanics who prefer to speak in Spanish rather than

English (indicating lower acculturation) are at lower risk, perhaps because they still retain the lifestyles-especially dietary habits- common in their country of origin, where fresh fruits and vegetables may be less expensive and more widely consumed."

The challenge is that three tomatoes in an inner-city grocery store can cost the same as a meal at McDonald's, Daviglus says. "Are you going to serve only tomatoes to the family? Of course not," she says. One potential remedy to lower the price of fruits and vegetables could be community gardens, which "should be established in every community. These are solutions that we need to discuss as remedies."

THE ROAD AHEAD

Going forward, Daviglus sees the need for further research to explore these issues, and she envisions individual papers on each of the major risk factors that examine how the social and economic realities like acculturation, for example, affect each of them.

As the Latino population in the U.S. continues to grow, and as this currently relatively young population group ages, their health will have important implications for the U.S. healthcare system. "We are going to be in trouble in a decade or two if we don't act now to prevent future cardiovascular and other chronic diseases," says Daviglus. "One important way we can prevent diseases is through education." This could involve, among other strategies, educational materials in waiting rooms, brochures from insurance companies and public service announcements, she added.

Daviglus compares those potential efforts to educational campaigns conducted during the last half-century against unhealthy lifestyle factors such as smoking and consumption of red meat, which used to be the hallmarks of prosperity. After studies showed the benefits of healthy eating habits and regular exercise-and the harmful health effects of smoking-unhealthy behaviors became less acceptable. Currently, adverse lifestyles and unhealthy diets high in sugar, fat and salt are more common among those lower on the socioeconomic scale, who have fewer resources and live in neighborhoods that may have few markets selling fresh produce and limited parks and health facilities, all of which impede the adoption of healthy lifestyles.

Disseminating the findings of this study to physicians will, of course, be critical, Daviglus says, "so they are aware of what to expect with regard to risk factors in the Hispanic population, and can effectively address the issues." With the advent of the Affordable Care Act, Daviglus says she hopes physicians will be able to promote prevention of cardiovascular and other chronic disease among a broader cross-section of the population, even if that's not why a given patient made an appointment.

"It's going to cost more if we don't start to address these looming problems now," Daviglus says. "The longer these risk factors remain uncontrolled by lifestyle changes or untreated when necessary, the greater the damage to the body."

In keeping with its mission of serving a diverse population, UI Health has led the way in individualizing therapies for specific groups of people, Garcia says. That has included a bio-banking effort across the entire clinical enterprise that provides access to tissue, plasma and serum samples, along with DNA and RNA.

"That will allow us, moving forward, to think about how we can apply and understand modifiers of disease susceptibility and disease severity in much more informed ways," he says. "A real-time example is our effort to provide genotyping for warfarin metabolism to all patients admitted to the hospital. Genotyping allows us to determine the optimal warfarin dose for each and every patient in the hospital while gaining important new understanding of the unique genetic differences amongst racial and ethnic patient populations that impact warfarin metabolism," Garcia added. "This will make the tests infinitely more valuable for the patients we serve."

Daviglus' research will help to refine these approaches, Garcia says. "I don't think it's far-fetched at all to think that within Hispanics/ Latinos of different ethnic backgrounds, certain therapies will work well in one group and not another group," he says. "We will need to individualize heart failure medications in that same way. We're so lucky to have that kind of research expertise here, to interact with UI Health as we move forward and try to provide the very best, high-quality, personalized health care for the people we serve."