Abstract P65: Arterial Stiffness Relationship With Periventricular and Deep White Matter Hyperintensities in a Middle-Aged Population

Abstract

Introduction and hypothesis: Periventricular white matter (PVWM) is perfused by perforators originating from the proximal large caliber cerebral arteries with direct transmission of systemic hemodynamic changes as compared to the deep white matter (DWM) that is perfused by distal perforators with dampened transmission. We hypothesized that PVWM hyperintensities (PVWMH) are more strongly associated with the systemic vascular properties representing arterial stiffness (AS) due to vascular aging and hypertension compared to DWM hyperintensities (DWMH). Methods: Apparently healthy first degree relatives of subjects with coronary artery disease who had brain MRI as participants in GeneSTAR were selected. PVWMH and DWMH volumes were computed by an automated analysis software. Arterial stiffness indicators included peak systolic blood pressure during treadmill test, pulse pressure (PP), brachial artery (BA) diameter, carotid distensibility index, and diastolic dysfunction estimated by filling and systolic emptying rates (SER) on sestamibi cardiac scan. Statistical analysis was completed using unadjusted and age-adjusted linear regression models in the cohort that was divided into 4 quartiles based on age distribution (1 st : 29-43, 2 nd : 44-51, 3 rd : 52-59, 4 th : 60-74). Results: 782 participants were included (age 51.05±10.6 years, 58.4% female, 39% African American, PVWMH volume 1977.01±5195.81 ml and DWMH volume 625.93±1108.37 ml). In the unadjusted analysis, PVWMH showed association with PP in the 1 st and 3 rd age quartiles (p= 0.02 and 0.03, respectively) and SER in the 2 nd and 4 th age quartiles (p=0.04 and 0.03). This relationship remained significant in the adjusted analysis for SER (p=0.047, and 0.032, respectively) and in the 1 st age quartile for PP (P=0.02). DWMH relationship with BA diameter was significant in the 2 nd age quartile in the unadjusted and adjusted models (P=0.011, and 0.02, respectively). DWMH was also associated with ratio of cardiac filling/SER (P=0.039 and 0.047) in the 1 st age quartile. Conclusions: In this exploratory analysis, AS measures show different relationships to PVWMH and DWMH across age groups in middle-aged population suggesting a potential mechanistic role of AS in WMH pathology.