Association of sympathovagal imbalance with arterial stiffness indices in women with risk factors for pregnancy-induced hypertension in first and third trimesters of gestation

Abstract

Background and Aim: Though contribution of sympathovagal imbalance (SVI) to arterial stiffness indices (ASI), and markers of CV risk in pregnancy-induced hypertension (PIH) has been reported, their association during early trimesters of gestation in PIH has not been studied. Therefore, in the present study, we have investigated the association of SVI with ASI in pregnant women with risk factors for PIH during their first and third trimesters of gestation. Methods: Blood pressure (BP), rate-pressure product (RPP), spectral analysis of heart rate variability (HRV), and arterial stiffness indices (ASI) were assessed in subjects of control group (normal pregnant women without having risk for PIH, n = 50) and study group (pregnant women with risk factors for PIH, n = 50). Independent association of LF:HF ratio to the various parameters were determined using multiple regression analysis. Results: It was observed that the ratio of low-frequency to high-frequency power (LF-HF ratio) of HRV, the sensitive indicator of SVI was significantly high in study group subjects starting from first trimester of pregnancy. SVI could be due to both sympathetic activation and vagal withdrawal. ASI was found to be significantly high in study group subjects compared to that of controls. LF-HF ratio had significant correlation and independent association with RPP (the marker of CV risk) and ASI. Conclusion: SVI is associated with arterial stiffness in pregnant women having risk factors for PIH. SVI and increased arterial stiffness could contribute to CV risks in pregnant women with risk factors for PIH.