Racism and Health Outcomes

 

Not long ago, I wrote about the role of race in predicting and treating disease. Recently, I had the pleasure of listening to David Chae, SciD, MA, professor at the Emory University Rollins School of Public Health, speak about racism and health outcomes—particularly cardiovascular risk and aging. While the two ideas sound similar, racism and its effect on people’s health is related to my last post but is a different concept.

“How does racism get under the skin?” Dr. Chae asked.  Discrimination is a process by which individuals are treated differently (and usually unfairly) on the basis of a particular characteristic (e.g. ethnicity, sex, sexual orientation, religion, age). Racism is a discriminatory ideology that extends beyond an isolated encounter; racism is often ingrained within society. The systemic discrimination that constitutes racism is thought to cause stress which can have serious health consequences, but how?

Scientists at Harvard developed the implicit association test (IAT) to measure a person’s racial bias, even if the person is unaware of any such bias. Respondents are first asked to associate images of faces to particular words (e.g. a Caucasian face with the word “white”). Then the subject is asked to associate words like “beautiful” with “good” and “horrible” with “bad.” The subjects are finally asked to associate words like “beautiful” or “horrible” with word clusters like “black/good” or “white/bad.” The rate of responding on each of these tasks is compared. If a subject takes longer to place a good word like “beautiful” with the word cluster “black/good”, then they are said to have an anti-black bias. It is also possible to have an anti-white bias. Take the test here and see where you stand.

In his talk, Dr. Chae quoted one statistic that reported 80% of Whites and 50% of Blacks have an anti-black implicit bias. Clearly, racism is not just about hating another group of people; Black people can have an implicit anti-black bias. This may be the result of a history of institutionalized racism prior to the civil rights movements in the United States, and cases of de facto racism that continue today. In 1939, Dr. Kenneth Clark conducted a test in which he presented Black children with two dolls and asked the child to choose the nicer doll. The dolls were identical in every way except one was White and one was Black. Most of the Black students indicated the White doll as nicer. This is evidence of internalized racism. Unfortunately, this test was repeated more recently, and the results were not different. Watch the video here.

In one study, Dr. Chae determined that Black men with an implicit anti-black bias, who reported more experience with racism and discrimination, also had a history of poor cardiovascular health. To quote Dr. Chae, “Internalized negative racial group attitudes themselves were associated with history of cardiovascular disease, and they moderated the impact of racial discrimination on these outcomes.” To measure negative racial group attitudes he used three items assessing whether the respondent agreed with negative statements regarding Blacks, specifically, whether Blacks are lazy, give up easily, and are violent. Dr. Chae will soon conduct a longitudinal study in which he will use the IAT as a tool to determine negative group attitudes and further explore the link to cardiovascular health.

But how does racism get under the skin and impact health? One measure scientists use is the level of c-reactive protein (CRP). CRP is found in the blood and levels rise in response to inflammation; it is also an indicator of poor cardiovascular health. Dr. Tene Lewis and colleagues at Yale University School of Public Health, found that while an African-American’s body mass index was positively correlated with the level of CRP in the blood, so was regular racial discrimination. The thought here is that perhaps stress from racism is putting biological stress on the body, causing CRP to rise.

Another measure of stress and aging can be telomere length. Telomeres are located at the end of our chromosomes. They are made up of repeating units and protect our chromosomes (which contain important genetic information) from being degraded. Over time, the telomeres themselves degrade and shorten in length. Dr. Chae noted a very nice analogy in which telomeres were compared to the plastic casing on the end of shoelaces; our chromosomes are the shoelaces. The plastic end of the shoelace, prevents the lace from fraying. However, eventually that plastic gets degraded and the shoelace begins to fray. Shorter telomeres are a sign of cellular aging (different from chronological age which is measured in years). Back in 2004, Dr. Elissa S. Epel from the University of California found that telomeres shorten at a faster rate in response to stress. Many scientists now explore whether stress resulting from racism also shortens telomere length.

Until recently, it has been hard to truly measure the impact of racism on health because racism is thought of as an intangible idea. It is important to find effective ways to measure racism, stress and aging so that we may keep exploring the link between racism and health. The sooner the links are untangled, the sooner we can devise a solution.