How do your environment and life experiences shape dementia risk

A national study that explores the relationship between Alzheimer's disease, environmental factors and lifetime experiences has been awarded $30.9 million from the National Institutes of Health (NIH). The award is the second round of NIH funding for The Neighborhoods Study, a collaboration between 24 Alzheimer's Disease Research Centers including UC Davis Health's center.

The study is led by the University of Wisconsin School of Medicine and Public Health. It examines environmental factors such as poverty, education, housing, employment and toxins - also known as the social exposome - and their link to Alzheimer's disease and related dementias (ADRD). It is the largest in the world to connect the social exposome with brain tissues and their disease biomarkers.

The Neighborhoods Study will assess lead-contaminated infrastructure exposure, job-related toxin exposures and heavy metals in brain tissue to better understand what makes certain populations more vulnerable to ADRD.

The study is expected to lead to ADRD prevention measures that are precisely tailored to populations at highest risk based on exposures. Its work focuses on risk mitigation and new interventions in ADRD, advancing knowledge of the relationship between exposome and dementia to improve health for all.

About The Neighborhoods Study

The Neighborhoods Study was started in 2021. It has supported the development of the Area Deprivation Index (ADI), a powerful tool used by the University of Wisconsin's Center for Health Disparities Research to develop thousands of health interventions and policies.

ADI aimed at achieving better health outcomes for people living in rural and urban neighborhoods with greatest need. It has demonstrated an association between neighborhood disadvantage increased odds of neurodegeneration, ADRD biomarkers and post-mortem ADRD neuropathology. It has also linked residency in high ADI neighborhoods across one's lifetime with increased risk of neurodegeneration and brain disease.

"We have known for some time the genetic and biological factors that contribute to ADRD, but growing evidence suggests that community and neighborhood-level factors may also influence ADRD risk," said Oanh Meyer, professor of neurology and Neighborhoods Study site principal investigator for UC Davis Health. "These factors are potentially modifiable, and thus important targets for prevention and intervention."

Meyer is research faculty with the Alzheimer's Disease Research Center and leads Vietnamese Insights into Cognitive Aging Program, or VIP.

"UC Davis is pleased to be one of the sites participating in this incredibly important research program," said co-director of the Alzheimer's Disease Research Center and epidemiologist Rachel Whitmer. "The Neighborhoods Study leverages numerous Alzheimer's research centers. By combining data from the different sites, we could uniquely achieve the statistical power to determine how factors related to people's context and life experiences contribute to biological indicators of both dementia and healthy brain aging."

Whitmer is the co-investigator at the UC Davis site. She is professor of public health sciences and neurology and chief of epidemiology at UC Davis Health.

The Neighborhoods Study is the largest of its kind linking brain tissue to life-long exposures to more fully examine the precise mechanisms by which the social exposome impacts ADRD risk and outcomes.