Associations between Aortic Stiffness, Cerebral Artery Resistance and White Matter Integrity in Women with a History of Preeclampsia

Purpose: Preeclampsia is a pregnancy complication characterized by new-onset hypertension and systemic organ dysfunction. Women with a history of preeclampsia (hxPE) have a greater cerebral white matter ischemic damage burden and a three-fold elevated risk of vascular dementia later in life compared with healthy pregnancy independent of traditional cardiovascular risk factors. Aortic stiffness promotes the transmission of deleterious pulsatile pressure to the distal cerebral circulation, resulting in increased cerebrovascular resistance (CVR) that contributes to compromised brain blood flow and structure. We hypothesized that young women with hxPE would have greater aortic stiffness and CVR compared to healthy pregnancy, and CVR would be related to lower cerebral white matter microstructural integrity (WMI). Methods: Women with hxPE (N=10) were matched with healthy pregnancy controls (N=11) by age (28-42 years), educational attainment, body mass index, and postpartum duration (1-5 years). Aortic stiffness was quantified as carotid-femoral pulse wave velocity (CFPWV). 4D flow and diffusion tensor magnetic resonance images were acquired to evaluate internal carotid and middle cerebral artery (MCA) blood flow velocity and WMI (fractional anisotropy), respectively (3T MRI, GE). CVR index was calculated as the ratio of central mean arterial pressure to regional flow velocity. Results: Women with hxPE tended to exhibit higher CFPWV compared with controls (6.3±0.8 vs 5.6±0.7 m/s, P=0.09 adjusted for mean arterial pressure). CVR did not differ at the internal carotid artery (2.2±0.4 vs 2.0±0.3 mmHg s cm -1 , P=0.30) but was higher at the MCA among women with hxPE (2.4±0.3 vs 2.1±0.4 mmHg s cm -1 , P=0.08). In the entire group, CFPWV was associated with greater CVR at the internal carotid (r=0.41, P=0.07) and MCA (r=0.48, P=0.03). Although WMI did not differ between groups, greater MCA CVR was related to lower WMI overall (r=-0.45, P=0.049) and in select white matter tracts (corpus callosum genu, r=-0.53, P=0.02; cingulum hippocampus, r=-0.43, P=0.06; superior frontooccipital fasciculus, r=-0.46, P=0.04). Conclusions: Women with hxPE had elevated aortic stiffness that was associated with greater CVR. Greater CVR was related to lower WMI in subcortical watershed regions susceptible to reduced perfusion. These findings indicate that aortic stiffness may contribute to early declines in WMI via CVR in women with hxPE. Supported by AHA Transformational Project Award (969732) to GLP and NIH grant 1S10OD025025-01 to VM This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.