In our gene-obsessed society, whenever one group differs from another on some measure of health, laypeople as well as experts reflexively leap to a genetic explanation. Higher rates of hypertension among African-Americans than Caucasian Americans? It must be their genes. That assumption is behind race-based medicine, too—the idea that different medications will work better for people of different races.
Next time someone hands you that line, send them to a paper published in the November issue of the journal Social Science and Medicine.
In it, scientists led by Roland James Thorpe of the Bloomberg School’s Hopkins Center for Health Disparities Solutions, while not ruling out genetic or other inherent biological factors, find that social environment is a big reason for the black-white hypertension disparity. “Our study found that nearly 31 percent of the hypertension disparity among African Americans and non-Hispanic whites is attributable to environmental factors,” Thorpe said. “These findings show that ethnic disparities could be linked to a number of factors other than race. Careful review of psychosocial factors, stress, coping strategies, discrimination and other personality characteristics could play a large role in reducing or eliminating the disparity.”
Translation: Not to put too fine a point on it, but living in a society where security guards at high-end stores eye you suspiciously, where cab drivers refuse to pick you up, where fellow students and work colleagues let you know in subtle and not-so-subtle ways that they think you’re where you are because of affirmative action—well, let’s just say that any and all of these are excellent ways to raise your blood pressure. Hypertension, in turn, can damage the heart and blood vessels, raising your risk of stroke, heart failure, heart attack and kidney failure. It affects some 65 million people in the U.S.
In a nutshell, the Hopkins scientists compared data from a study called the Exploring Health Disparities in Integrated Communities-SWB (EHDIC-SWB) Study, which was run in a racially-integrated community where income did not vary by race, with data from a broad-based national survey called the National Health and Nutrition Examination Survey. They focused on hypertension, defined as systolic blood pressure of 140 or more, or diastolic blood pressure of 90 or more. Comparing the two data sets, the scientists found that race alone elevated blood pressure about one-third less in the racially-integrated community than nationally.
“These findings support our theory that the disparity [in rates of hypertension] is likely caused by environmental factors along with several external factors, and not biological differences among race groups, as previously suspected,” said co-author Thomas LaVeist.
It's great to live in an integrated (and presumably less racist than the national average) community as an adult, but biological changes triggered by social experiences kick in long before adulthood. So, here’s the next question: what would happen to race-based health disparities if children grew up in a race-blind society, never feeling the blood-pressure-elevating sting of racism? Just wondering.