Circulating levels of the antiangiogenic marker soluble FMS-like tyrosine kinase 1 are elevated in women with pregestational diabetes and preeclampsia: angiogenic markers in preeclampsia and preexisting diabetes.

P reeclampsia is characterized by the development of proteinuria and hypertension after 20 weeks gestation, and it is associated with maternal and fetal morbidity. Preeclampsia affects 5% of pregnancies, though women with preexisting diabetes are three to four times more likely to develop preeclampsia (1). Preeclampsia is associated with altered angiogenic factors, including increased levels of circulating soluble FMS-like tyrosine kinase 1 (sFlt1) and reduced levels of vascular endothelial growth factor and placental growth factor (PlGF). Hypertension and proteinuria of preeclampsia may be caused by an imbalance of these angiogenic factors (2–10). Circulating sFlt1, an antiangiogenic protein, binds to proangiogenic proteins, vascular endothelial growth factor, and PlGF, preventing their interaction with endothelial cell receptors and inducing endothelial dysfunction. Rats given sFlt1 develop proteinuria, hypertension, and glomerular endotheliosis, which are hallmarks of preeclampsia (3). Alterations in sFlt1 and PlGF are observed several weeks before symptoms (2). It is unknown whether alterations in sFlt1 and PlGF are present in women with diabetes who then develop preeclampsia or whether a different pathway is responsible. Ultimately, it would be helpful to have a way to diagnose and predict preeclampsia in women with pregestational diabetes, as they frequently have preexisting hypertension and/or proteinuria, which make it difficult to differentiate superimposed preeclampsia. We evaluated a small group of women with diabetes and compared levels of sFlt1 and PlGF at delivery in both those who developed preeclampsia and those who did not. We hypothesized that women with preexisting diabetes who developed preeclampsia may also have elevations in sFlt1 and decreases in PlGF.