Evidence of a state of increased insulin resistance in preeclampsia.

Similarities in certain biochemical variables between preeclampsia and the insulin resistance syndrome imply a possible link between insulin resistance and preeclampsia. We measured insulin sensitivity by the minimal model technique between 29 and 39 weeks of gestation in 22 preeclamptic and 16 control women, whose glucose tolerance was first confirmed as normal by an oral glucose tolerance test. In addition, we measured the fasting levels of serum C-peptide, uric acid, lipids, and lipoproteins. Preeclamptic women showed a higher insulin response (P = .001) during the oral glucose tolerance test than the controls. Insulin sensitivity in preeclamptic women (1.11+/-0.15 x 10(-4) x min(-1) x microU/mL) was 37% lower (P = .009) than in control women (1.77+/-0.19 x 10(-4) x min(-1) x microU/mL). The free fatty acid (FFA) concentration in preeclamptic women (0.17+/-0.01 g/L, P = .0004) was 70% higher than in control women (0.10+/-0.01 g/L). Also, baseline serum levels of C-peptide, uric acid, and triglyceride were higher in preeclamptic women. Insulin sensitivity increased fourfold to fivefold within the first 3 postpartum months, but insulin sensitivity in preeclamptic women was still 26% lower (P = .04) than in control women. Preeclampsia is a state of increased insulin resistance, and it persists for at least 3 months after pregnancy. This may be a pathogenetic factor in preeclampsia and may contribute to the excess cardiovascular morbidity among women with prior preeclampsia.