Plasma Concentrations of Asymmetric Dimethylarginine (ADMA) in Colombian Women With Pre-eclampsia

To the Editor: Worldwide, pre-eclampsia is a leading cause of maternal death, affecting 3% to 5% of all pregnancies. 1 ] To assess plasma ADMA concentration in pregnant women living in a high-risk area for pre-eclampsia, we sequentially enrolled, from November 2000 until February 2002, 160 women (67 women with pre-eclampsia [49 moderate and 19 severe cases] and 93 healthy pregnant controls) (TABLE All women were primigravid and younger than 25 years. Inclusion criteria for the pre-eclampsia group were: more than 20 weeks of gestation, blood pressure of 140/90 mm Hg or higher in 2 separate measurements, and proteinuria (0.3 g in 24 hours or a urine dipstick reading of 2+ for protein with no evidence for urinary tract infection). Controls were clinically healthy women with onset of labor at 37 or more weeks of gestation. None of the controls had hypertension or proteinuria at the onset of labor. Ethnicity (as determined by a validated questionnaire 6 ) and exclusion criteria for both groups (history of renal, cardiac, metabolic [diabetic], or autoimmune disease) were assessed by the enrolling physicians. The study was approved by the ethics committee of the Universidad Auto noma de Bucaramanga, Colombia, and all women enrolled provided written informed consent. Plasma concentrations of ADMA, symmetric dimethylarginine, and L-arginine were measured blinded (within-assay and betweenassay variations for ADMA, 1.7% and 2.5%, respectively; limit of detection, 0.004 mol/L) by minor modifications of an established method. Our sample size had a greater than 93% power