Gestational hypertension but not pre-eclampsia is associated with insulin resistance syndrome characteristics

The aim of this study was to assess whether the metabolic characteristics of insulin resistance syndrome are present in pre-eclamptic (PE), gestational (GH) and chronic hypertensive (CH) pregnancies. Glucose and insulin serum concentrations, both fasting and after oral administration of a glucose tolerance test, were evaluated in 26 hypertensive pregnant women (10 PE, 10 GH and six CH patients) and in 10 healthy controls during the third trimester of gestation. Insulin sensitivity was assessed using the hyperinsulinaemic-euglycaemic clamp technique. The plasma concentrations of triglyceride (TG), high density (HDL), low density (LDL), and very low density (VLDL) lipoprotein cholesterol, apolipoproteins AI and B, and non-esterified fatty acid (NEFA) were also measured. Women with GH exhibited approximately 40% lower steady-state insulin sensitivity index (ISI) compared to controls (3.75 versus 6.34, P < 0.03), as well as approximately 33% higher mean plasma TG (3.57 versus 2.68 mmol/l, P < 0.01), and approximately 69% higher mean NEFA (0.59 versus 0.35 mmol/l, P < 0.01). Women with PE showed similar ISI but reduced insulin and glucose areas under curve compared to controls (P < 0.006, P < 0.0005 respectively). Women with PE also had higher HDL-cholesterol and apo-AI than controls. Patients with CH had similar lipid and carbohydrate metabolism to control subjects. In conclusion, women with GH exhibit metabolic features similar to those of patients with insulin resistance syndrome, suggesting that similar abnormalities could be involved in the pathogenesis of these disorders. In contrast, our data do not support an association between insulin resistance syndrome and hypertension in pregnant women with PE and chronic hypertension.