MICROVASCULAR DYSFUNCTION IN PREECLAMPSIA AND GESTATIONAL DIABETES: A CASE-CONTROL STUDY

Objective: Hypertensive disorders of pregnancy (HDP) and gestational diabetes (GDM) are leading causes of maternal and fetal morbidity and mortality. Vascular dysfunction plays a crucial role in the development of the systemic symptoms and signs, as well as in the increased maternal cardiovascular risk later in life. An increase in glycocalyx degradation has recently been detected as an additional sign of vascular dysfunction. The glycocalyx thickness can be measured non-invasively in vivo using sidestream dark field microscopy at the sublingual region. The software calculates the perfused boundary region (PBR) in μm, an inverse parameter of endothelial glycocalyx dimension. In our study, we aimed to assess the association between the PBR of the endothelial glycocalyx in sublingual vessels and the development of pregnancy complications.Design and method: We enrolled 135 nulliparous women during their first obstetric evaluation at the University of Bologna, Italy. We performed sidestream dark field microscopy of the sublingual region in two timepoints: 11+0-15+6 weeks of gestation and 24+0-28+6 weeks of gestation. The composite outcome considered was the development of a HDP and/or GDM. Of the 135 participants, 33 developed at least one of the conditions, while 102 had uncomplicated pregnancies. Results: Women with a pregnancy complicated by HDP or GDM had a reduced glycocalyx thickness both in vessels from 8 to 25 microns and in vessels from 4 to 7 microns compared to women with normotensive pregnancies, suggesting involvement of both the microcirculation and the biggers microvessels like arterioles. The presence of subclinical endothelial dysfunction as early as the first trimester, preceding the onset of HDP and GDM, allows us to hypothesize a key role in the pathogenesis of major obstetric conditions. Indeed, in our logistic regression models, both PBR 4-7 and PBR 8-25 microns were able to predict the development of at least one index condition in the studied population. Conclusions: In our study, women who develop HDP or GDM presented with widespread alteration of the micro and macrovascular system, suggesting the possible contribution of endothelial glycocalyx derangement occurring during pregnancy to the vascular maladaptation in pregnancies complicated by HDP and GDM.