Experiencing discrimination may increase the chance of dying, especially from cardiovascular-related causes, according to a new study that followed participants for nearly two decades.
Previous studies have found links between discrimination and conditions such as heart disease, diabetes and obesity. For the new study, published Wednesday in the American Heart Association journal Circulation: Cardiovascular Quality and Outcomes, researchers wanted to delve deeper into the relationship between discrimination and mortality to find out who it affects the most.
The study included 1,633 Black, 1,403 Hispanic and 2,473 white participants ages 45 to 84 with no prior history of cardiovascular disease. Research took place in New York City, Los Angeles, Chicago, Baltimore, St. Paul, Minnesota, and Forsyth County, North Carolina. Researchers examined participants six times between 2000 and 2018.
Participants answered questions about being treated unfairly at any point in their lives in six major areas, such as being denied a promotion or being prevented from moving into a neighborhood. Other questions covered discrimination experiences in day-to-day life, such as being treated with less courtesy or as lacking intelligence.
Lifetime discrimination was much more common among Black participants, at 61% compared to 39% among Hispanic participants and 37% among white participants.
After adjusting for age, race, income, high blood pressure, diabetes and other factors, the study found that each one-point increase in lifetime discrimination was associated with a 6% rise in all-cause mortality and a 15% increase in coronary heart disease, stroke and other cardiovascular-related deaths. When researchers broke down the lifetime discrimination data by race and ethnicity, they found the rise in cardiovascular deaths was highest and reached statistical significance only for Black participants, who had an 18% increased risk.
Wayne Lawrence, the study's lead author and a research fellow at the National Cancer Institute, said that while he'd expected to see an overall higher death rate for people experiencing discrimination, he didn't expect it to be "so much higher for cardiovascular mortality."
The effect of everyday discrimination on cardiovascular mortality risk reached statistical significance only among white participants, who had an increased risk of 51%. The researchers said this may reflect white participants with lower socioeconomic status or who belong to ethnic groups that experience historical prejudice, such as Jewish people.
Breaking down the results by gender, the study found men who reported experiencing everyday discrimination had a slightly higher cardiovascular death rate than women, Lawrence said. While researchers didn't explore the reasons behind the gender differences, "previous studies suggest women are better than men at finding and using social support and other ways of coping with discrimination," he said.
Lawrence called on medical professionals and policymakers to be more proactive in "screening patients for psychosocial stressors, providing resources that might mitigate their adverse health effects, and finding new policies and interventions to end discrimination."
He also called for future studies that explore which forms of discrimination have the greatest impact on health and the best methods for "buffering the adverse health effects of discrimination."
Lawrence also would like to see further research on how the racial makeup of neighborhoods affects how people cope with discrimination. While the study did look at the effect of residential segregation, it didn't find enough data to draw conclusions, he said.
There's also a need for research on how discrimination impacts the health of Asian Americans, he said.
Dr. Karol Watson, who was not involved in the research, said the study was limited by its observational structure and the subjective nature of discrimination.
Still, she praised it as "an important study that tries to tease out the association between experiences of discrimination and mortality."
Watson, a cardiologist and professor of medicine at the David Geffen School of Medicine at the University of California, Los Angeles, said doctors need to factor discrimination "into our risk estimations" and encourage patients to seek out social support.
She called for future studies on how social support, mindfulness and psychological interventions might improve outcomes.
"Discrimination is obviously difficult to modify," she said, "but patients can try to modify their reactions to experiences of discrimination."