Understanding Alzheimer’s Disease Disparities in African Americans

Alzheimer’s disease (AD) presents a pressing public health challenge, particularly within racial and ethnic minority groups in the U.S. Notably, African Americans experience a prevalence of AD that is approximately two times higher than that of White individuals. This disparity can largely be attributed to a combination of social determinants of health, including unequal access to healthcare, limited educational opportunities, and higher prevalence of risk factors such as cardiovascular disease and diabetes. Understanding these elements is crucial for addressing the growing impact of AD on African American communities.

The Role of Social Determinants of Health

Health disparities often arise from complex social structures. For African Americans, factors such as socioeconomic status and systemic biases in healthcare contribute immensely to the increased risk of Alzheimer’s. Access to quality medical care, early diagnosis, and treatment options are often less attainable, exacerbating the effects of pre-existing health conditions. Additionally, educational disparities can hinder awareness and understanding of both Alzheimer’s and dementia, leading to delayed action and care.

Gaps in Research Focused on African Americans

While significant research has focused on gene expression in relation to Alzheimer’s, much of it has centered on European-ancestry individuals or mixed cohorts, often neglecting the African American demographic. Many studies on AD lack sufficient representation of African Americans, making it challenging to derive meaningful conclusions about genetic risk factors that may uniquely affect this population. In previous studies, African American participants were either not specified or represented in such small numbers that significant findings were elusive.

Landmark Study Pinpoints Genetic Variance

A pivotal study conducted at the Boston University Chobanian & Avedisian School of Medicine has shed light on this under-researched area. This investigation stands out as the largest of its kind to focus on brain tissue from African American donors. Researchers analyzed gene expression data from post-mortem prefrontal cortex tissue of 207 African American brain donors—125 diagnosed with AD and 82 controls—uncovering a number of differentially expressed genes, several of which had not been implicated in AD in earlier genetic studies.

The Significance of ADAMTS2

A key finding of this study was a 1.5-fold increase in the expression of the gene ADAMTS2 in the brain tissue of African American individuals with autopsy-confirmed Alzheimer’s. Remarkably, this gene was also identified as a significant marker in an independent study involving a larger sample of individuals of European ancestry. This consistency in findings speaks volumes about the underlying biological processes shared across racial groups.

Shared Biological Pathways

The fact that certain genetic markers align across populations opens new avenues for research, indicating that there may be universal biological processes at play in the development of Alzheimer’s. Corresponding author Dr. Lindsay A. Farrer emphasized this point, noting that the shared expression of ADAMTS2 suggests a common genetic underpinning for Alzheimer’s risk, regardless of ancestry. Such discoveries not only deepen our understanding of AD but also highlight the importance of diverse participant representation in genetic studies.

Implications for Future Research

Understanding the implications of this shared gene expression is paramount. As Dr. Farrer noted, while many AD risk variants are population-specific, this research emphasizes the potential for ADAMTS2 to serve as a key therapeutic target in combating Alzheimer’s disease. Future studies need to focus on this gene to further elucidate its role and establish effective interventions tailored to the needs of diverse populations.

The ongoing research into Alzheimer’s disease, particularly in the African American community, indicates significant potential for uncovering new therapeutic pathways and promoting health equity. By addressing these disparities and centering research on underrepresented populations, we can work toward a more inclusive understanding of Alzheimer’s disease that ultimately benefits all communities affected by this devastating condition.

References

Logue, MW et al. (2025). Novel differentially expressed genes and multiple biological pathways for Alzheimer’s disease identified in brain tissue from African American donors. Alzheimer’s Dementia, 21(10): e70629. doi: 10.1002/alz.70629.