Mild cognitive impairment (MCI), dementia and stroke are substantially higher among blacks
aged 45+, and among residents of the southeastern region of the US. The REasons for
Geographic And Racial Differences in Stroke (REGARDS) Study is national, longitudinal cohort
study of ~ 30,000 blacks and whites designed to advance the understanding of the
epidemiology of cognitive decline and stroke, and the contributors to racial and geographic
disparities in these outcomes. The current application has three aims:
1. Identify social, cardiovascular, and environmental mechanisms of racial and geographic
disparities in incident vascular contributions to cognitive impairment and dementia (VCID).
With assessment in mid-life and over a decade of longitudinal cognitive data, REGARDS is
uniquely positioned to identify vascular, social, and behavioral mechanisms underlying
disparities in VCID, and modifiable pathways on which interventions may narrow disparities
in VCID. After completion of a nested calibration/confirmation study to develop an algorithm
for the classification of MCI and dementia, we will characterize racial and geographic
disparities in VCID and determine if interventions on mediators would diminish or eliminate
2. Answer as-yet-unanswered questions in stroke and cerebrovascular disease epidemiology.
By continuing the successful approaches for stroke surveillance among 17000 active cohort
members, the study will assess the association of risk factor changes and novel biomarkers
quantified with the completion of the second in-person exam with stroke risk and disparities
in stroke risk. In addition, with the aging of the cohort, this aim will provide greatly needed
information on stroke epidemiology in the elderly.
3. Utilize incident risk factor data and biospecimens to identify pathways for development of
incident hypertension and diabetes, with the goal of understanding the impact on incident
VCID and stroke. We have documented that ˜30% of the racial disparity in stroke risk is
attributable to racial disparities in prevalence of hypertension and diabetes, and the study
will investigate the biomarker pathways contributing to the higher incidence of hypertension
and diabetes in blacks.
Each proposed aim addresses a topic of profound public health impact, and REGARDS
progress to date uniquely positions the study to address these aims using proven approaches
in an efficient manner.