There is evidence from epidemiologic studies that gestational hypertension (GH) carries an increased risk of cardiovascular disease later in life. This study was an attempt to determine whether GH in a previous pregnancy, defined as newly developed hypertension after 20 weeks gestation, is associated with endothelial dysfunction or carbohydrate and lipid metabolic changes typical of insulin resistance in currently healthy women. Endothelium-dependent brachial artery flow-mediated dilatation (FMD) and endothelium-independent nitroglycerin-induced dilatation were estimated ultrasonically in 15 women with a history of GH and 15 others who had had normal pregnancies. The interval between delivery and evaluation was at least 12 months and averaged 20 months. Women with gestational diabetes were not included.
Apart from blood pressure, there were no significant demographic or pregnancy differences between the 2 groups of women. Fasting insulin levels were 60% higher in women with previous GH, and insulin resistance, expressed as homeostasis model assessment (HOMA), was 80% greater. Fasting glucose levels were comparable in the 2 groups and all women had normal lipid profiles. Nevertheless, previous GH was associated with 20% lower levels of high-density lipoprotein (HDL) cholesterol and 60% higher levels of free fatty acids. Women with past GH had higher total and free testosterone levels, which, however, remained within the normal range. Although all women were normotensive, both systolic and diastolic pressures were significantly higher in those with previous GH. FMD in the previous GH group was nearly 55% that of control women, but there was no difference in nitroglycerin-induced dilatation. Linear regression analysis showed that total testosterone correlated strongly and negatively with FMD; correlation with free testosterone was somewhat less. FMD also correlated negatively and closely with HOMA and fasting insulin, and it correlated positively with HDL cholesterol and body mass index. Total testosterone accounted for 34% of the variance in FMD, and HOMA contributed 22% more.
Endothelial dysfunction is characteristic in healthy women having GH diagnosed in a previous pregnancy. There also are early signs of disordered carbohydrate, lipid, and hormone metabolism. These findings might help to explain reports of increased cardiovascular disease in these women.