Higher cholesterol and insulin levels in pregnancy are associated with increased risk for pregnancy-induced hypertension

Hyperinsulinemia and dyslipidemia are known to be associated with essential hypertension but their role in pregnancy-induced hypertension remains unclear. We performed a case-control study comparing cholesterol, insulin, and glucose levels in the early third trimester of pregnancy among 31 women who developed pregnancy-induced hypertension (PIH) (either preeclampsia [n = 6] or nonproteinuric gestational hypertension [n = 25]), with 31 women remaining normotensive through pregnancy. As compared with women remaining normotensive, women subsequently developing PIH had higher fasting cholesterol levels (279 v 247 mg/dL; P= .02) and higher fasting insulin levels (13.3 v 7.9 μU/mL; P= .03), although fasting glucose levels and levels of glucose and insulin after glucose load did not differ significantly between groups. In comparing hypertensive subgroups, fasting insulin levels were significantly higher among women who subsequently developed preeclampsia, but not among those subsequently developing nonproteinuric gestational hypertension. Although women developing PIH had higher pregravid body mass index (25.1 v 22.6 kg/m2, P= .06), fasting cholesterol and insulin levels were associated with risk for PIH even after adjustment for body mass index and age (relative risks for one unit increase, respectively: 1.02 (P= .03) and 1.12 (P= .03). Higher fasting cholesterol and insulin levels in mid- to late pregnancy are associated with increased risk for PIH. These observations support a role for insulin resistance in the development of this complication of pregnancy.