Lifetime discrimination linked to 40% higher risk of dementia, study finds

An increased risk of dementia may be associated with prejudice throughout one's life, according to recent research from Wake Forest University School of Medicine.

Published in the February issue of Alzheimer’s & Dementia, 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.

In the study, participants were contacted by telephone annually and invited to participate in five follow-up in-person clinic examinations from 2000 to 2018, per the release.

“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.

The data based on life experiences

The research team acquired information from self-reported lifetime and daily experiences of discrimination. Participants in the lifetime discrimination scale were asked if they had ever experienced unfair treatment in six different categories, such as being passed over for a promotion or being mistreated by the police.

The perceived cause of the unjust treatment, such as race, religion, gender, physical characteristics, socioeconomic status, or sexual orientation, was also requested of the participants.

All MESA participants reported encountering prejudice at some point in their lives at a rate of 42 percent, whereas Black adults reported having it at 72 percent. With a median follow-up of 15.7 years, 466 incident instances of dementia were recorded. Dementia risk was higher in people who reported prejudice throughout their lives in more than two domains as opposed to none.

“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 observed no apparent difference in the degree of relationship between race or ethnicity and dementia.

Study abstract:

Discrimination negatively impacts health and may contribute to racial/ethnic disparities in dementia risk. Experiences of a lifetime and everyday discrimination were assessed among 6509 Multi-Ethnic Study of Atherosclerosis (MESA) participants. We assessed the association of discrimination with incidence of dementia including adjustment for important risk factors, cohort attrition, and we assessed for effect modification by race/ethnicity. Prevalence of any lifetime discrimination in MESA was 42%, highest among Black adults (72%). Over a median 15.7 years of follow-up, there were 466 incident cases of dementia. Lifetime discrimination, but not everyday discrimination, was associated with incident dementia (Wald p = 0.03). Individuals reporting lifetime discrimination in ≥2 domains (compared to none) had greater risk for dementia (hazard ratio: 1.40; 95%: 1.08, 1.82) after adjustment for sociodemographic, clinical, and behavioral risk factors. Associations did not differ by race/ethnicity. These findings demonstrate an association of greater experiences of lifetime discrimination with incident dementia.