Epidemiologic Determinants of Cardiac Structure and Function in Rural Residents: RURAL ECHO

ABSTRACT
Rural dwelling adults in the US South suffer disproportionate cardiovascular disease (CVD) burden and
mortality. The Appalachia and Mississippi Delta (AMD) regions are particularly at risk, embedded in the stroke,
heart attack and heart failure (HF) mortality belts, where the determinants are multifactorial. Echocardiography
is an ideal methodology to study CVD and determine high risk imaging phenotypes for incident heart failure
owing to its ability to noninvasively assess cardiac structure and function simultaneously. Due to the excess of
CVD in the AMD region, we therefore expect a high prevalence of abnormal cardiac structure and function
among rural adults, but this has not been explicitly shown. The NHLBI-funded Risk Underlying Rural Areas
Longitudinal (RURAL) cohort study, by assessing a broad array of phenotypic, biologic and social determinants
of health represents a unique, cost-effective opportunity to implement a study to fill the gaps described, reduce
excess CVD burden and achieve health equity for all Americans. The long-term goal of this proposal is to
understand the burden of adverse cardiac remodeling in the absence of symptoms (i.e., Stage B HF) in the
AMD region and factors contributing to it so that interventions during subclinical disease states may avert
clinical HF later in life. The overall objective of this application is to establish a unique cohort, named RURAL
Echo (Echocardiographic Determinants of Cardiac Structure and Function in Rural Residents). Using the
infrastructure of the parent study’s mobile examination unit (MEU) – ‘a clinic on wheels’ – we will perform
echocardiography on all participants at baseline to characterize cardiac structure and function using a novel
artificial-intelligence (AI) echo approach. Our central hypothesis is that there is a significant burden of Stage B
HF, which is associated with exposures spanning multiple domains. We will achieve our objectives through
these specific aims: (Aim 1) Use AI Echo and meticulous core lab analysis to extensively characterize cardiac
structure and function in the RURAL study cohort with implications for public health impact of deploying AI
echo in rural settings; (Aim 2) Determine associations of AI Echo findings with known traditional biologic risk
factors and comorbidities; and (Aim 3) Determine associations of AI Echo findings with emerging social
determinants of health and establish if these associations are mediated by traditional biologic risk factors and
comorbidities. The proposed study will provide the largest and most comprehensive echocardiographic dataset
focused on rural adults, and will be the first to untangle the degree and relative importance of the association
between biologic and social factors on Stage B HF among rural adults. RURAL Echo promises to yield new
knowledge on rural cardiovascular health that is highly relevant to individual and US public health.

Grant Number: 5R01HL157531-04
NIH Institute/Center: NIH
Principal Investigator: Gerald Bloomfield