Cerebrovascular Reactivity and Vascular Activation in Postmenopausal Women With Histories of Preeclampsia

Abstract

Cerebrovascular reactivity (CVR) is reduced in patients with cognitive decline. Women with a history of preeclampsia are at increased risk for cognitive decline. This study examined an association between pregnancy history and CVR using a subgroup of 40 age- and parity-matched pairs of women having histories of preeclampsia (n=27) or normotensive pregnancy (n=29) and the association of activated blood elements with CVR. Middle cerebral artery velocity was measured by Doppler ultrasound before and during hypercapnia to assess CVR. Thirty-eight parameters of blood cellular elements, microvesicles, and cell-cell interactions measured in venous blood were assessed for association with CVR using principal component analysis. Middle cerebral artery velocity was lower in the preeclampsia compared with the normotensive group at baseline (63±4 versus 73±3 cm/s; P=0.047) and during hypercapnia (P=0.013-0.056). CVR was significantly lower in the preeclampsia compared with the normotensive group (2.1±1.3 versus 2.9±1.1 cm·s·mm Hg; P=0.009). Globally, the association of the 7 identified principal components with preeclampsia (P=0.107) and with baseline middle cerebral artery velocity (P=0.067) did not reach statistical significance. The interaction between pregnancy history and principal components with respect to CVR (P=0.084) was driven by a nominally significant interaction between preeclampsia and the individual principal component defined by blood elements, platelet aggregation, and interactions of platelets with monocytes and granulocytes (P=0.008). These results suggest that having a history of preeclampsia negatively affects the cerebral circulation years beyond the pregnancy and that this effect was associated with activated blood elements.

Keywords: hypercapnia; middle cerebral artery; monocytes; platelet aggregation; pregnancy.

Conflict of interest statement

Disclosures

The authors have no conflicts of interest to disclose.

© 2017 American Heart Association, Inc.

Figures

Figure 1. Middle cerebral artery velocity (MCAv) and cerebrovascular conductance index (CVCi) during hypercapnia

Data are mean ± SEM. Left: MCAv vs. end tidal carbon dioxide (ETCO2) during the stepped hypercapnia protocol (top panel) and the calculated MCAv reactivity slope (bottom panel). Right: CVCi vs. ETCO2 during the stepped hypercapnia protocol (top panel) and the calculated CVCi reactivity slope (bottom panel). Women with normotensive pregnancy (NP) are shown in black and women with preeclampsia (PE) are shown in grey *P < 0.05 compared to NP.