National Longitudinal Study of Adolescent to Adult Health (Add Health): Wave VI Cognition and Early Risk Factors for Dementia Project

Project Summary Alzheimer's Disease and Related Dementias (ADRD) are projected to affect 14 million Americans by 2050. To date, though, research on the signs and symptoms of ADRD has been sparse in early midlife populations, especially at the national level. It is crucial to conduct such research because early changes in cognitive

functioning and the accumulation of risk factors for ADRD can begin decades before concrete signs and symptoms emerge. The challenging search for the causes of ADRD has made it clear that prospective and comprehensive data—including detailed social, biological, and health measurements across the life course—

are needed to identify key predictors of ADRD. As such, the National Longitudinal Study of Adolescent to Adult Health (Add Health) provides an extraordinary opportunity to study the early origins of cognitive functioning/change and ADRD risk in a nationally representative cohort that has been followed since

adolescence and will be in their mid-40s in the next wave of data collection (Wave VI). The overall goal of this project is to collect and disseminate critical data related to cognitive, physical, and sensory functioning in conjunction with the Add Health Wave VI Core Project to facilitate identification of early risk factors for later life

ADRD. Adding such rich measures to Wave VI of Add Health will make possible tracking of cognitive, sensory, and physical functioning across the life course; coupled with the testing of biological risk markers, it will also lay the foundation for detecting signs of cognitive impairment and ADRD risk in early midlife. These new data,

when combined with Add Health's existing 25-year collection of extraordinarily rich multi-level and longitudinal measures and its new Wave VI data, will also aid in the scientific community's understanding of the interplay of social, behavioral, and biological factors leading to ADRD in later life. Moreover, because Add Health is a very

diverse sample, adding these data to Wave VI will greatly increase understanding of cognitive, physical, and sensory functioning within health disparity populations. The project's specific aims are to: 1) Collect new in- depth, in-person assessments of cognitive functioning in early midlife for a nationally representative and

racially/ethnically diverse subsample of participants in Wave VI; 2) Collect automated, (largely) web-based measures of cognition in early midlife for all participants in Wave VI and compare them with our in-person measures of cognition to assess their feasibility and value; 3) Include assessments of physical and sensory

functioning in early midlife for Wave VI participants of Add Health; 4) Test for biological markers of ADRD risk and cognitive function in early midlife; 5) Clean, document, disseminate, promote, and support the data collected in this project for the scientific community. All told, this project will collect and disseminate innovative

data to thousands of researchers that will facilitate the rigorous study of cognition and risk factors for later life ADRD among a diverse nationally representative sample of early midlife Americans.