Association of serum asymmetric dimethylarginine, homocysteine, and L-arginine concentrations during early pregnancy with hypertensive disorders of pregnancy

Background: Our previous study suggested that a lower l-arginine level (<70 mu M) at early gestation is associated with pregnancy-induced hypertension. The maternal asymmetric dimethylarginine (ADMA) and homocysteine (Hcy) concentrations also have been reported to be increased in hypertensive disorders of pregnancy (HDP). These molecules have a key role in metabolism of nitric oxide. The aim of this study is to determine the most useful predictor of HDP at early gestation. Methods: The concentrations of ADMA and Hcy at each of three periods in normal pregnancy were determined, and the values compared between the normal pregnancy and HDP groups. Moreover, the possible risk factors for the development of HDP also were evaluated using a multivariate logistic regression model and propensity score (PS). Results: The maternal ADMA concentration was significantly elevated with advance of gestational age, while Hcy concentration was decreased from early to mid-gestation and increased from mid- to late-gestation in normal pregnancy. The maternal Hcy concentration at early gestation was significantly higher in the HDP group compared to that in the normal group. A higher maternal Hcy level (>7.2 mu M) in early pregnancy was independently associated with the development of HDP (PS-adjusted odds ratio=4.47, 95% confidence interval=1.51-12.82), as well as pre-pregnancy overweight [body mass index (BMI)>25kg/m(2)], primipara status, and a lower maternal l-arginine level (<70 mu M). Conclusions: The risk factors, such as overweight (BMI>25kg/m(2)) before pregnancy, primipara status, higher Hcy (>7.2 mu M), and lower l-arginine (<70 mu M) concentration in early pregnancy, for development of HDP were detected.