First trimester zonulin levels and adiposity as predictive indices of gestational diabetes mellitus

Background: This study was aimed at determining the levels of serum zonulin during the first trimester in pregnant women and to examine the relationship between zonulin and obesity in the development of gestational diabetes mellitus (GDM). Available evidence suggests that the permeability of the gut may be associated with obesity and insulin resistance both of which are characteristics of GDM. Methods: This was a prospective longitudinal study in which a cohort of 314 pregnant women was monitored from first trimester at the Volta Regional Hospital, Ho, Ghana. Maternal serum zonulin and lipids were analyzed during the first trimester, and body mass index (BMI) was calculated for each participant. Glucose challenge tests (GCT) and oral glucose tolerance tests (OGTT) were done between 24 and 28 weeks of pregnancy, and diagnosis of GDM was made in accordance with the American Diabetes Association (ADA) criteria. Results: Women who developed GDM had elevated serum zonulin levels with sensitivity, specificity, and cutoff points of 80.95%, 80.41%, and > 47.5 ng/mL respectively in predicting GDM. With positive predictive value (PPV) and negative predictive value (NPV) of 0.708 and 0.986, respectively, zonulin has been shown by this study to be a good predictor of GDM. After adjusting for maternal age and BMI, obese pregnant women with elevated plasma zonulin were 109 times likelier to develop GDM as compared to those with normal BMIs. Conclusions: Zonulin levels are increased significantly during the first trimester of pregnancy in women with GDM, and these increases precede the onset of GDM.