Study finds association between lifetime experiences of discrimination and incidence of dementia

WINSTON-SALEM, N.C. – Feb. 28, 2023 – According to new research from Wake Forest University School of Medicine, people who experience discrimination during their lifetimes have an increased risk of dementia.

The study appears in the February issue of Alzheimer’s & Dementia, the journal of the Alzheimer’s Association.

“We need a better understanding of how experiences of discrimination impact health and dementia risk as well as racial/ethnic disparities in dementia,” said Mike Bancks, Ph.D., M.P.H., assistant professor of epidemiology and prevention at Wake Forest University School of Medicine and corresponding author of the study.

In the study, researchers assessed data from the Multi-Ethnic Study of Atherosclerosis (MESA), a medical research study involving more than 6,500 men and women from six communities in the United States—Baltimore; Chicago; Forsyth County, North Carolina; Los Angeles; New York City; and St. Paul, Minn. Participants were contacted by telephone annually and invited to participate in five follow-up in-person clinic examinations from 2000 to 2018.

The research team gathered data from self-reported experiences of lifetime and everyday discrimination. For the lifetime discrimination scale, participants were asked whether they had been treated unfairly in six domains such as being denied a promotion or treated unfairly by police. Participants were also asked to indicate the perceived reason for the unfair treatment such as race, religion, gender, physical appearance, income or sexual orientation.

For the everyday discrimination scale, participants were asked to indicate the frequency with which certain experiences of unfair treatment occur in their day-to-day life.

The prevalence of experiencing any lifetime discrimination was 42% across all MESA participants and higher among Black adults at 72% with experiences of discrimination. Over a median of 15.7 years of follow-up, there were 466 incident cases of dementia. Individuals reporting lifetime discrimination in more than two domains (compared to none) had a greater risk for dementia.

“Our findings suggest an association between greater experiences of discrimination during one’s lifetime and higher risk for dementia,” Bancks said. “In alignment with other MESA findings, it’s clear that Black adults bear an unequal burden of exposure to discrimination, and discrimination is harmful to health.”

Researchers also noted that the strength of association between discrimination and dementia did not appear to differ by race/ethnicity.

According to Bancks, there are a few potential mechanisms that may link experiences of lifetime discrimination to cognitive impairment such as chronic stress, receiving inadequate or delayed health care, and undiagnosed or untreated high blood pressure, but additional research is needed.

“Future studies should assess how the accumulation of experiences of discrimination are related to dementia risk to help guide strategies to intervene on discrimination and dementia risk,” Bancks said.

This study was supported by National Heart, Lung and Blood Institute grants R01HL127659, 75N92020D00001, HHSN268201500003I, N01-HC-95159, 75N92020D00005, N01-HC-95160, 75N92020D00002, N01-HC-95161, 75N92020D00003, N01-HC-95162, 75N92020D00006, N01-HC-95163, 75N92020D00004, N01-HC-95164, 75N92020D00007, N01-HC-95165, N01-HC-95166, N01-HC-95167, N01-HC-95168 and N01-HC-95169; the National Center for Advancing Translational Sciences grants UL1-TR-000040, UL1-TR-001079 and UL1-TR-001420; and by National Institute on Aging grants R01AG054069 and 1RF1AG054474.