Amino acids levels in early pregnancy predict subsequent gestational diabetes

Background We aimed to estimate the performance of amino acids levels in predicting the risk of subsequent gestational diabetes mellitus (GDM). Methods A total of 431 women at 12 to 16 weeks of gestation in the Department of Obstetrics and Gynecology of the Second Affiliated Hospital of Soochow University were recruited. High-performance liquid chromatography electrospray tandem mass spectrometry was used to measure amino acids levels in maternal blood at 12 to 16 weeks of gestation. At 24 to 28 weeks of gestation, all participants were administered 75-g oral glucose tolerance tests for the diagnosis of GDM. Results Alanine, isoleucine, and tyrosine levels in early pregnancy were significantly different between women who developed GDM and those who remained normal glucose tolerant. Logistic regressions showed that after adjustments for age, parity, body mass index, family history of diabetes, γ-glutamyltranspeptidase, triglycerides, fasting glucose and fasting insulin levels, alanine (odds ratio [OR], 1.46; 95% CI, 1.05-2.04; P = .027), isoleucine (OR, 1.48; 95% CI, 1.12-1.96; P = .0062), and tyrosine (OR, 1.46; 95% CI, 1.07-2.03; P = .020) levels in early pregnancy were independently associated with subsequent GDM. The addition of isoleucine and tyrosine into the conventional model improved the area under curve from 0.692 to 0.737 (P = .036) and significantly increased the net reclassification improvement (+13.7%, P = .0025). Conclusions The present study suggests that elevated isoleucine, tyrosine, and alanine levels are independently and significantly associated with subsequent incidence of GDM. New models including conventional risk factors, isoleucine and tyrosine levels in early pregnancy might help physicians identify high-risk population of GDM.