Population Studies: Quantify the exposome

Quantify the exposome in existing and new AD cohorts to gain a more precise measure of environmental exposure factors and their relationship to AD risk and individual trajectories of disease progression. These studies should employ a life-course approach across diverse populations (e.g., race, ethnicity, immigration status, geographical region, education, age, gender) and incorporate methods aimed at understanding how ancestry, race/ethnicity, sex, gender, and socioeconomic disparities interact with exposome factors to modulate AD risk.

Provide supplemental funding to at least 6 clinical research studies to explore the impact of environmental exposure on the pathogenesis of AD and AD-related dementias and on responsiveness to treatment.
Launch at least three clinical research studies that incorporate deep molecular phenotyping, new environmental and behavioral sensors and mobile health technologies for cognitive assessment to detect the impact of the exposome on AD risk and resilience.
Provide funding to enhance existing data resources with information on early life exposures/events.
Provide funding to enhance administrative data linkages.
Support research that will enable comparative analysis of the exposome within and among populations to understand the impacts of exposures on disease outcomes.
Develop open and democratized data resources and FAIR (findable, accessible, interoperable, reusable) data practices to increase the reach of AD/ADRD-relevant exposome research across a wide-array of stakeholder groups and encourage the adoption of exposomic-related ontologies for data interoperability.

Summary of Key Accomplishments

NIA supports nationally representative cohorts that capture data on environmental factors for dementia risk, including the Health and Retirement Study (HRS), Harmonized Cognitive Assessment Protocol (HCAP) in the U.S. NIA also supports studies harmonized to HRS in several other countries. HRS collects demographic, economic, behavioral, cognitive, and contextual information as well as objective health measures via collection of blood samples for approximately 20,000 people ages 50 and older. The HCAP enables researchers to measure and understand dementia risk in ongoing longitudinal studies of aging around the world by using similar methods. In 2024, NIA renewed HRS and HCAP. The renewal includes larger samples of Black/African American and Hispanic/Latino populations in HCAP; contextual data to capture new elements of the exposome, ranging from microscopic to macro-level exposures; and expanded aging and AD/ADRD-relevant blood-based biomarkers.

NIA also supports educational cohort studies seeking to understand education and other social factors as risk and protective factors for dementia across the life course. In addition, NIA funded four awards beginning in 2022 that are working to enhance measures of educational exposures and cognitive assessments in existing studies. NIA made an award in 2024 to establish a new Exposome Coordinating Center to foster collaboration and accelerate life course research on the social, behavioral, economic, and environmental exposures that shape AD/ADRD outcomes and inequities.

NIA has also funded sixteen administrative supplements to support research infrastructure on exposome studies in AD/ADRD. To spark new advances in the field, NIA issued several funding opportunities in FY24 to fund exposome research as part of NIA’s larger efforts to enable a precision environmental health approach to risk reduction and disease prevention. These funding opportunities will support projects that characterize the impact of toxicants, like air pollution, metals, per- and polyfluoroalkyl substances (PFAS), and pesticides, on brain aging and dementia.

The key accomplishments summary is current as of June 2024.