Defining the role of race
in health research
April 15, 2009
Eight years ago, when the New England Journal of Medicine
published two studies comparing the effects of drugs
between black and white patients, a debate ensued on the
journal's editorial pages and later in the media.
Some experts said race has no place in medical research. One
editorialist in the journal said that "attributing differences in a
biological end point [in this case, the reaction to a drug] to race
is not only imprecise, but also of no proven value in treating an
individual patient."
Others said making racial distinctions in this context was
justified and even valuable. A NEJM editorialist in this camp
held that addressing the effects of race on the response to drugs
will "be of great help to physicians in their attempt to choose the
best therapy for … patients of different races."
The debate is by no means settled, but researchers have
continued to refine the way they think about race and ethnicity in
health and health care. For a perspective on
the issue, Research Currents spoke with
Leonard Egede, MD, MS, a physicianresearcher
at the Ralph H. Johnson VA
Medical Center in Charleston, S.C. Egede
directs VA's Center for Disease Prevention
and Health Interventions for Diverse
Populations. He is also an associate
professor at the Medical University of
South Carolina and directs the school's
Center for Health Disparities Research.
Q: When we discuss "race" in the context
of health research, are we talking about
actual biological differences among
people or about social and cultural
differences?
A: It depends on the nature of the research.
In terms of disparities research, my approach,
and what the literature is beginning to
suggest, is that race is really a social
construct. A lot of what we deal with has
little to do with the genetics of race. It's
really an issue of the culture you belong to
and how you identify yourself. Even if
you're multiracial, if you identify as being
black, or Hispanic, or a Pacific Islander, that
will determine to a large extent the
interactions you have, the behaviors you pick
up, your value system, your views on life. In
fact, most researchers take race and ethnicity
and blend them together. Ethnicity is even
more of a social construct than race is.
Q: Some racial or ethnic groups are at
higher risk for certain diseases. So does
this have more to do with race per se or
with cultural factors such as diet, lifestyle
and socioeconomic status?
A: If we look at diabetes as an example, we
see it's a mixture. Diabetes is a polygenic
disease, so you have multiple genes involved,
but the genes are defined by your
environment. So there's some genetic basis for
type 2 diabetes, but it's not just genes; it's also
the environment. Behaviors and environment
are just as important as the genes.
Q: What have we learned about how the
biological and cultural factors associated
with race or ethnicity interact?
A: I recently gave grand rounds where I spoke
on how the environment uncovers latent
genetic predisposition to diabetes in ethnic
minority groups. Multiple studies show that
the longer people stay in America, the more
likely they are to gain weight and become
physically inactive, and the more their risk of
diabetes increases. Several studies have
compared Japanese immigrants to the U.S.
with those who stayed in Japan. Over time,
the risk of diabetes among those who
immigrated to America increased two to
threefold across the different studies. So here
you have people with a similar genetic
makeup, but the environment has clearly
impacted their risk for disease. I coauthored a
paper that looked at the length of residence in
America and the risk of cardiovascular
disease. In general, we found that among
immigrants from diverse ethnic backgrounds,
when they've been here for 15 years, the risk
of being obese, having high cholesterol and
smoking increases dramatically.
Q: What is it about life in America that
accounts for these health changes among
these immigrants?
A: You have to give credit to this country.
It's a great nation with lots of opportunities.
It provides lifestyle options that may not be
readily available in other countries. As it
happens, some of the things that make life
pleasurable and enjoyable also increase the
risk of disease.
Q: VA and other health systems are
increasingly focusing on genomic
medicine, which uses patients' genetic
information to individualize their care. Is
this likely to result in better care for
minority patients?
A: In terms of pharmacogenomics—tailoring drugs based on specific genes or
genetic responses—I think we'll start seeing
more and more of these studies, but I doubt
they'll be primarily along racial lines. It
may be that certain genes are more
prevalent in certain ethnic groups, so you
could have certain drugs being targeted
more to those groups. But from an
economic standpoint, the pharmaceutical
industry will have little incentive to make
drugs that target only certain groups. More
importantly, it appears there are few
diseases where you really have a unique
response by race.
Q: There's a lot of talk now about
comparative effectiveness research—large studies that compare different medical treatments for a
particular condition. Are these types of studies—which VA has
been doing for years—likely to benefit minority groups along
with the general population?
A: There have to be large enough numbers of minorities in these
trials. That's when you can begin to see how different groups
benefit differently from a particular treatment. And you can start
to think about how to tailor the intervention to meet the needs of
unique groups. That's an important area we need to pursue in
terms of outcomes research. Generally speaking, however, to date
there hasn't been enough diversity in the populations included in
most of these trials. What we need is to involve more minorities in
research so we have big enough sample sizes to be able to stratify
by race and look at racial differences in outcomes.
Q: Hasn't VA done a fair amount of research specifically
looking at how interventions benefit different racial groups?
A: That's true. Some of us are already doing studies where we
design an intervention, and our primary aim is to test whether the
intervention works at all. Then we have a secondary hypothesis to
test whether the intervention works differently between whites
and blacks, for example, or between whites and Hispanics. Some
of this research is already ongoing, and people are only going to
do more and more of it. We've begun to recognize that racial
groups do respond differently to many interventions, and maybe
these interventions need to be tailored to specific groups.
Q: Why are minorities still underrepresented in health
research in the U.S. in general?
A: This is partly the result of location. In most parts of the country,
you may end up having two, maybe five percent minority
representation. With a lot of the drug studies, they don't have enough
minority groups and they don't have a formal hypothesis to test
differences across groups. Overall, we're behind. VA and the National
Institutes of Health have done a lot in trying to increase diversity in
the pool by requiring applicants to state how they're going to address
gender and ethnic diversity, but we need to do more.
Q: What else can be done to increase minority representation
in research?
A: One answer is something we do a lot of in VA—partnering with
other sites where you can have a larger pool of minorities. The
push now should be toward doing more multisite studies. They're
more expensive, but you end up having data that are more
generalizable to the whole population, including minorities. It also
helps to have a more diverse workforce. This starts with the
investigator. Minority investigators are more likely to be interested
in doing research about minorities, and I believe they have a better
chance of recruiting from minority populations. I can tell you
anecdotally from some of my studies that I'm actually able to
recruit more African Americans than whites or Hispanics. This
extends to other study personnel as well. When people are being
recruited by people of similar ethnicity, they are more inclined to
want to participate. The concerns that may stem from the distrust
of the past are minimized.
This article originally appeared in the April 2009 issue of VA Research Currents.