Depressed Kallikrein Generation in Women With Preeclampsia: A Matched Cross-Sectional Study

Increased contact activated endogenous thrombin potential in pregnant women with preeclampsia

Preeclampsia is a worldwide contributor to maternal and fetal morbidity and mortality. Women with preeclampsia are in a hyper-coagulable state with increased risk of thromboembolic disease later in life compared with normal pregnant women. The contact system (CAS) in plasma can mediate thrombin generation and is an important contributor to thrombus growth, but the activation of CAS during pregnancy complicated by preeclampsia is not yet elucidated, and CAS may play a role in the pathophysiology of preeclampsia. Therefore, the aim of the study is to address thrombin generation, and in particular, the capacity of the CAS-mediated pathway in patients with preeclampsia compared with pregnant controls. One hundred and seventeen women with preeclampsia and matched controls were included. The project was registered at www.clinicaltrials.gov as NCT04825145. CAS and tissue factor induced thrombin generation, proteins C and S, antithrombin, and histidine-rich glycoprotein (HRG) were assessed. Women with preeclampsia had significantly increased CAS and tissue factor-induced endogenous thrombin potential (ETP), and HRG compared with controls, P  = 0.022, P  = 0.024, and P  = 0.02, respectively. The concentrations of protein C and antithrombin were significantly reduced in the preeclampsia group, P  = 0.024 and P  < 0.0001, respectively. No significant difference in the concentration of protein S was detected, P  = 0.06. This study demonstrates a significant increased CAS-induced ETP and an overall decrease of important regulators of coagulation in women with preeclampsia compared with controls. These aspects can contribute to the hyper-coagulable state characterizing preeclampsia.

Fibrinolytic Changes in Women with Preeclampsia

Objectives

Preeclampsia (PE) is a serious complication of pregnancy. The fibrinolytic system play crucial roles regarding placentation and evolution of PE.

Aim

To study comprehensively components of the fibrinolytic system and fibrin lysability in women with PE.

Design and Methods

117 women with PE and matched controls were included. Tissue type plasminogen activator (t-PA), plasminogen, PAI-1, plasmin inhibitor (PI), D-dimer, the fibrinolytic potential of dextran sulphate euglobulin fraction (DEF), PAI-2, polymere PAI-2, fibrin clot lysability, thrombin activatable fibrinolysis inhibitor (TAFI) and fibrinogen were assessed.

Results

Women with PE had significantly increased concentrations of t-PA and PAI-1, whereas the plasma concentration of PAI-2 was significantly lower compared to controls, p < 0.0001. Polymere PAI-2 was detected in both groups. DEF, TAFI and fibrinogen were not different between the groups. D-dimer was significantly increased and plasminogen/PI together with fibrin clot lysability time decreased in the PE-group, p  =  0.0004 p  =  0.04, p  =  0.03, p < 0.0001 respectively.

Conclusion

This study demonstrates that PE is associated with an affected t-PA/PAI-1 system, decreased PAI-2 and increased fibrin lysability. Furthermore, PAI-2 has the potential to polymerize during pregnancy.