Photographs of Constance and Jessica Guthrie, a mother and daughter, adorn a bedroom in Fredericksburg, Virginia, on September 19, 2022. Though some risk factors for Alzheimer’s may vary by race, the significant disparities among racial groups cannot be attributed solely to genetics. Img source: projects.apnews.com
May 03, 2024 Story by: Editor
Recent research indicates that racial discrimination toward Black Americans may elevate the risk of developing Alzheimer’s disease (AD) later in life.
A study revealed that Black Americans who faced racism in their 40s and 50s had higher serum levels of AD biomarkers p-tau181 and neurofilament light (NfL) more than a decade later.
“We know that Black Americans are at an elevated risk of Alzheimer’s disease and other dementias compared to non-Hispanic White Americans, but we don’t fully understand all the factors that contribute to this disproportionate risk,” stated Michelle Mielke, PhD, co-author and professor of epidemiology and prevention at Wake Forest University School of Medicine, in a press release.
Statistics show AD is twice as prevalent in Black Americans (18.6%) compared to Whites (10%). Mielke noted that this disparity cannot be solely attributed to genetic differences, suggesting that racism and its associated stress may be contributing factors.
The study findings were published online on April 10 in *Alzheimer’s and Dementia*.
AD Biomarker Testing
To delve into the connection between racism and AD risk, researchers analyzed data from the Family and Community Health Study, a multisite, longitudinal investigation involving over 800 families across the United States.
Between 2002 and 2005, blood samples and information on racial discrimination were collected from 255 middle-aged Black Americans. These samples were tested for serum phosphorylated tau181 (p-Tau181), a marker of AD pathology; NfL, a nonspecific marker of neurodegeneration; and glial fibrillary acidic protein (GFAP), a marker of brain inflammation.
Participants answered questions about racial discrimination, including experiences of disrespectful treatment, racial slurs, harassment from law enforcement, and social exclusion due to their race.
The study group consisted of 212 females and 43 males, with a mean age of 46, and 70% of participants lived in urban areas.
Stress-Related Findings
Initially, in 2008, when participants were about 46 years old, there was no correlation between racial discrimination and elevated AD biomarkers. However, 11 years later, at an average age of 57, a significant link was found between experiencing racism in middle age and higher levels of both p-Tau181 (r = 0.158, P ≤ .012) and NfL (r = 0.143, P ≤ .023). No significant association was observed between reported discrimination and GFAP levels.
“These findings support the hypothesis that unique life stressors encountered by Black Americans in midlife become biologically embedded and contribute to AD pathology and neurodegeneration later in life,” the study authors wrote.
The researchers speculated, based on prior studies, that the stress from discrimination might be linked to reductions in hippocampal and prefrontal cortex volumes and general neurodegeneration.
Mielke emphasized the need for future studies to focus on the impact of racism on Black Americans to better understand their dementia risk.
“This research can help inform policies and interventions to reduce racial disparities and reduce dementia risk,” she said. Source: Medscape
A noted limitation of the study was the absence of amyloid biomarkers, as participants had non-detectable levels of amyloid, likely due to the use of serum versus cerebrospinal fluid.
