Abstract WMP101: Plasma Proteomic Determinants Of White Matter Hyperintensities And Covert Brain Infarction In The Cardiovascular Health Study

Abstract

Background: Identification of novel biomarkers of cerebral small vessel disease is critical to elucidate pathophysiology and guide therapeutic development for prevention. We evaluated plasma proteomic associations of clinically asymptomatic, covert brain infarction (cBI) and white matter hyperintensity (WMH) burden on cranial magnetic resonance imaging (MRI) in the population-based Cardiovascular Health Study (CHS). Methods: Eligible CHS participants underwent one or two cranial MRI scans (~5 years apart) and aptamer-based SOMAScan platform measurement of up to 7288 plasma proteins concurrent with the initial MRI. cBI was defined by MRI signal characteristics and size ≥ 3 mm, and WMH burden was graded (WMG) 0 (least) to 9 (most severe). The relationship between 1-standard deviation increase in each log 2 -normalized plasma protein fluorescence was modeled separately with incident cBI and WMG worsening (≥1 grade increase) using multivariable relative risk regression, adjusting for demographics, estimated glomerular filtration rate (eGFR), and stroke risk factors. In secondary analyses, multivariable linear regression evaluated the cross-sectional relationship between each plasma protein with number of cBI and WMG on initial MRI. Bonferroni correction, based on the number of principal components that explained 99% of the protein fluorescence variance in CHS participants, accounted for multiple comparisons (p<2.1x10 -5 (0.05/2377)). Results: For eligible participants (n=2615), mean age was 74.4 ± 4.9 years, 61.7% were women, and 16.4% were Black. After adjustment for demographics, eGFR, and stroke risk factors, multiple circulating proteins were associated with cBI and WMG (Table). Conclusion: Multiple plasma proteins - implicated in systemic inflammation, fatty acid metabolism, neuronal adhesion/migration, and cellular cytoskeletal integrity/remodeling - were independently associated with cBI and WMG in a cohort of older adults.