Metabolic and Hormonal Factors Related to Hypertensive Pregnancy : Special Attention to Insulin Resistance, Sympathetic Over-activity, and Hyperandrogenism
Year: 2014
Type: dissertation
Study design: Observational Study
Abstract: Hypertension is a common medical problem encountered during pregnancy. New-onset hypertension, pregnancy-induced hypertension (PIH) with (pre-eclampsia) or without proteinuria develops in previously normotensive women. PIH has been found to be a state of insulin resistance and sympathetic over-activity. Angiopoietin-like protein 6 (Angptl6) and adipocyte fatty acid-binding protein 4 (FABP4) seem to be insulin-sensitivity regulators and they could serve as insulin sensitivity biomarkers before and during complicated pregnancy. This study consists of five sub-studies with four different study populations. In the first and second prospective observational studies there were 72 relatively overweight (BMI more or as much as 24 kg/m2) nulliparous women. In the study we assessed at 24 and/or 32 weeks of gestation predictive parameters associated with subsequent pre-eclampsia. Insulin sensitivity was assessed via the Matsuda insulin sensitivity index (ISI) and by way of homeostatic model assessment of insulin resistance (HOMA-IR). Maternal serum levels of FABP4, high sensitivity C-reactive protein (hs-CRP), androgens, and plasma noradrenaline levels were determined. In a subgroup of 47 women, serum concentrations of Angptl6 were quantified. In the third study blood pressure was measured in different body positions and sympathetic activity was assessed by way of noradrenaline and adrenaline levels for 36 women. In the fourth study diurnal blood glucose profiles were assessed in 178 women with gestational diabetes mellitus (GDM). In the fifth study, 37 women with a history of pre-eclamptic or with prior normotensive first pregnancies were studied 23 24 years after delivery. Insulin sensitivity was assessed via the Matsuda whole-body ISI and serum concentrations of androgens were assessed. Relatively overweight women who subsequently developed PIH had no evidence of insulin resistance, hyperandrogenism or inflammation at 24 or 32 weeks of gestation compared with those who remained normotensive (I). At 24 weeks of gestation, serum FABP4 concentrations and SBP after 10 minutes standing in an orthostatic test were associated with the subsequent development of PIH (I). Serum Angptl6 levels in the second trimester of pregnancy were higher in women who subsequently developed PIH (II). In pre-eclampsia plasma noradrenaline levels were elevated (III). The rise in noradrenaline levels could already be seen at 32 weeks of gestation in women with subsequent PIH, at least in relatively overweight women (I). In diurnal glucose profiles there was a greater increase in blood glucose from 4 am to 8 am in women with GDM and chronic hypertension compared with women who remained normotensive (IV). At climacteric age, women with prior pre-eclampsia did not present with an increased incidence of metabolic syndrome, altered insulin resistance or hyperandrogenism (V). The present work supports the presence of sympathetic over-activity in hypertensive pregnancy. It is suggested that two regulators of insulin sensitivity, Angptl6 and FABP4, may have potential roles in the development of PIH.
Source: Työväentutkimus Vuosikirja
Author: Anna Tuuri
Language: English
Subfield: Obstetrics and Gynecology
Field: Medicine
Domain: Health Sciences
Open Access status: green
Funder: Helsingin Yliopisto
OpenAlex ID: W2284052653