Relationship between first-trimester serum level of 25-hydroxyvitamin D3and gestational diabetes mellitus

Abstract

Objective To explore the relationship between serum level of 25-hydroxyvitamin D3 (25- [OH]D3) at first trimester of pregnancy and gestational diabetes mellitus (GDM). Methods The prospective case-control study involved 1 768 women who took antenatal care at Guangdong Women and Children Hospital from June 2011 to March 2013. All subjects were enroled at 6-13 weeks of gestation and blood sample was taken to measure glucolipid metabolic index and 25-[OH]D3 levels. At 24- 28 weeks of gestation, all subjects took 75 g oral glucose tolerance test (OGTT) . The subjects were divided into GDM group (n=350, maternal age (29±5) years) and control group (n=1 418, maternal age (29±4) years) according to results of OGTT and fasting blood glucose (FBG) , and then 25-[OH] D3 levels and glucolipid metabolic index between the two groups were compared. Data was analyzed by using independent t test, Pearson correlation, logistic regression. Results The progestational body mass index (BMI) of GDM patients was significantly higher ((22.6±3.1 vs 20.5±2.1) kg/m2, t=5.913, P 0.05).Among women who developed GDM, maternal serum 25-[OH] D3 concentrations at first trimester of pregnancy were significantly lower than the controls ((23.8±3.3 vs 37.8±12.8) nmol/L, t=17.936, P<0.05); The serum 25-[OH] D3 levels were significantly and negatively correlated with HOMA-IR (r=–0.867, P<0.05), TG (r=–0.133, P<0.05), progestational BMI (r=-0.244, P<0.05); Women who were classified as being deficient for vitamin D had a 1.669- fold increased subsequent risk of GDM, as compared with vitamin D sufficient women after adjustment for progestational BMI, TG, LDL-C, FBG, HOMA-IR (adjusted OR:1.669; 95%CI: 1.460-1.912, P<0.05);The receiver operating characteristic curve (ROC) analysis showed that the sensitivity was 85.9% and the specificity was 83.7% in predicting GDM at point of 28.2 nmol/L of serum 25-[OH] D3 concentration. Conclusions The serum 25-[OH] D3 concentrations at first trimester of pregnancy were significantly decreased in women who were subsequently developed GDM. Maternal vitamin D deficiency at first trimester of pregnancy is associated with an elevated risk for GDM. Key words: Diabetes, gestational; Calcifediol; Insulin resistance