RESUMO
Objective: To investigate the relationship and predictive value of first-trimester pregnancy-associated plasma protein A (PAPP-A), maternal factors, and biochemical parameters with gestational diabetes mellitus (GDM) in southern China mothers. Methods: This study recruited 4872 pregnant women. PAPP-A, the free beta subunit of human chorionic gonadotropin (free ß-HCG), fasting plasma glucose (FPG), total cholesterol (TC), triglycerides (TG), and high- and low-density lipoproteins (HDL, LDL) were measured at 11-13+ weeks of gestation. GDM was diagnosed based on a 75 g oral glucose tolerance test at 24-28 weeks of gestation. We performed stepwise logistic regression analysis to determine the odds ratio (OR) and the 95% confidence interval (CI) of GDM. We used Receiver Operating Characteristic (ROC) curves with the area under the curve (AUC) to evaluate the predictive value of PAPP-A, maternal factors, and biochemical markers. The significance of the differences between the AUC values was assessed using the DeLong test. Results: GDM was diagnosed in 750 (15.39%) women. Independent factors for GDM were age, pre-gestational BMI, GWG before a diagnosis of GDM, previous history of GDM, family history of diabetes, FPG, TG, LDL, PAPP-A, and TC. The AUC of PAPP-A was 0.56 (95% CI 0.53-0.58). The AUC of a model based on combined maternal factors, biochemical markers, and PAPP-A was 0.70 (95% CI 0.68-0.72). Differences in AUC values between PAPP-A alone and the model based on combined maternal factors, biochemical markers, and PAPP-A were statistically significant (Z= 9.983, P<0.001). Conclusion: A Low serum PAPP-A level in the first trimester is an independent risk factor for developing GDM later in pregnancy. However, it is not a good independent predictor although the predictive value of a low serum PAPP-A level increases when combined with maternal factors and biochemical markers.
RESUMO
Background: Maternal subclinical hypothyroidism (SCH) has been associated with adverse pregnancy outcomes. This study aimed to explore whether SCH in the first trimester contributed to the development of gestational diabetes mellitus (GDM). Materials and Methods: A total of 8,777 pregnant women who first visited before 13 weeks and 6 days of gestation and accepted routine prenatal service at the Third Affiliated Hospital of Sun Yat-Sen University from January 2015 to September 2018 were recruited in this study. Thyroid functions (thyroid stimulating hormone [TSH], free T4, and thyroid peroxidase antibody [TPOAb]) were measured before 13 weeks and 6 days of gestation and data of 7,536 subjects with TSH ≥0.1 mIU/L were analyzed. A 2-hour 75-g oral glucose tolerance test was performed between 24 and 28 gestational weeks. Chi-square test and multivariate logistic regression analysis were applied to evaluate the relationship between SCH and GDM. Results: The prevalence of SCH in this population was 7.53%. After stratifying the relationship between SCH and GDM according to TSH concentrations (slightly elevated TSH: ≥2.5, <4.0 mIU/L; moderately elevated TSH: ≥4.0, <10.0 mIU/L) and TPOAb status, a moderately elevated TSH combined with positive TPOAb (23.9% vs. normal 13.0%, chi-square = 6.317, p = 0.012) was found to increase the incidence of GDM. Furthermore, after adjusting for confounders (maternal age, educational levels, parity, and pregestational body mass index [preBMI]), the SCH group still exhibited a higher risk of GDM (relative risk [RR] 1.867, 95% confidence interval [CI] 1.018-3.424). Conclusion: Our findings indicated that SCH during early pregnancy, in the presence of moderately elevated TSH levels and positive TPOAb, might lead to an increased risk of GDM.