Abstract TP125: Blood Biomarkers of Systemic Inflammation in Individuals With Brain Arterial Dilatation and Dolichoectasia

Background: Brain arterial dilatation is a core feature of dolichoectasia, and is associated with higher risk of stroke and vascular events. The role of systemic inflammation in brain arterial dilatation is uncertain. Methods: We measured blood levels of lipoprotein-associated phospholipase A2 (Lp-PLA2), myeloperoxidase (MPO), high-sensitivity C-reactive protein (hsCRP), and procalcitonin (PCT) in 538 NOMAS participants (mean age 71±8, 42% men, 60% Hispanic) who underwent brain time-of-flight MRA. Brain arterial diameters were normalized and averaged to obtain a global, anterior and posterior circulations measures of dilation. The concentration of each inflammatory biomarker was normalized to facilitate comparison, and to create an inflammation score consisting of the average of the four biomarkers. Generalized linear models were used to assess for main effects and statistical interactions by sex given known differences in arterial size. Results: Greater levels of MPO were associated with global and anterior circulation dilatation whereas greater levels of PCT were associated with posterior circulation dilatation (table 1). A higher inflammation score was associated with global and posterior circulation, but not anterior circulation, dilatation. There was a statistical interaction between MPO and sex (P=0.06). In a stratified model, the association between MPO and global arterial dilatation was significant in men (B=0.164±0.057, P=0.004) but not in women (B=0.053±0.054, P=0.33). There were no sex-based interactions for any of the other three inflammatory biomarkers. Conclusion: The inflammation markers MPO and PCT were associated with global and regional measures of brain arterial dilatation. The strength of the associations with MPO was greatest in men while the association with PCT was greatest for the posterior circulation. Understanding the physiopathology of these associations may uncover novel therapeutic targets for dolichoectasia.