Perspectives on diagnostic strategies for hyperglycaemia in pregnancy - Dealing with the barriers and challenges: Europe

The relationship between fasting plasma glucose in the first trimester of pregnancy and the incidence of gestational diabetes in Iran

AIMS

This study aimed to investigate the relationship between fasting plasma glucose in the first trimester of pregnancy and the incidence of gestational diabetes.

METHODS

This descriptive-analytical study was conducted using the merging data from two prospective cohort studies that were carried out from 2015 to 2018 in Ahvaz, southwest of Iran. Logistic regression and ROC curves were used to evaluate the predictive power of risk factors.

RESULTS

Of all 1270 pregnant women studied, 454 (35.75%) had gestational diabetes who were compared with the other 816 (64.25%) healthy women. The area under the curve (AUC) of fasting glucose for the first pregnancy visit was 0.80 (95% CI: 0.76-83), and the optimum fasting glucose cut-off point was 85.5 mg/dL with a sensitivity of 71% and a specificity of 69%. AUC of the combination of fasting glucose at the first visit with body mass index ≥25 kg/m² and family history of diabetes was calculated to be 0.85 (CI, 0.82-0.88) and 0.84 (CI, 0.79-0.89) respectively.

CONCLUSION

Fasting plasma glucose in the first trimester of pregnancy is a relatively good predictor of gestational diabetes. If this factor is combined with other risks, its diagnostic value will increase.

The Predictive Value of miR-16, -29a and -134 for Early Identification of Gestational Diabetes: A Nested Analysis of the DALI Cohort

Early identification of gestational diabetes mellitus (GDM) aims to reduce the risk of adverse maternal and perinatal outcomes. Currently, no circulating biomarker has proven clinically useful for accurate prediction of GDM. In this study, we tested if a panel of small non-coding circulating RNAs could improve early prediction of GDM. We performed a nested case-control study of participants from the European multicenter ‘Vitamin D and lifestyle intervention for GDM prevention (DALI)’ trial using serum samples from obese pregnant women (BMI ≥ 29 kg/m²) entailing 82 GDM cases (early- and late- GDM), and 41 age- and BMI-matched women with normal glucose tolerance (NGT) throughout pregnancy (controls). Anthropometric, clinical and biochemical characteristics were obtained at baseline (<20 weeks of gestation) and throughout gestation. Baseline serum microRNAs (miRNAs) were measured using quantitative real time PCR (qPCR). Elevated miR-16-5p, -29a-3p, and -134-5p levels were observed in women, who were NGT at baseline and later developed GDM, compared with controls who remained NGT. A combination of the three miRNAs could distinguish later GDM from NGT cases (AUC 0.717, p = 0.001, compared with fasting plasma glucose (AUC 0.687, p = 0.004)) as evaluated by area under the curves (AUCs) using Receiver Operator Characteristics (ROC) analysis. Elevated levels of individual miRNAs or a combination hereof were associated with higher odds ratios of GDM. Conclusively, circulating miRNAs early in pregnancy could serve as valuable predictive biomarkers of GDM.

Oral glucose tolerance test results in early pregnancy: A Finnish population-based cohort study

AIMS

To analyze early-pregnancy oral glucose tolerance test (OGTT) results and differences between early- and late-pregnancy OGTT results in a population-based cohort.

METHODS

From 3/2013 to 12/2016, pregnant women in South Karelia, Finland, were invited to undergo a 2-hour 75 g OGTT at 12-16 weeks' gestation (OGTT1) and, if normal, repeat testing at 24-28 weeks (OGTT2). Early and late gestational diabetes (GDM) were diagnosed using the same nationally endorsed criteria (fasting [FPG], 1- or 2-hour plasma glucose ≥5.3, ≥10.0 or ≥8.6 mmol/L, respectively).

RESULTS

In OGTT1 (n = 1401), the mean (SD) FPG, 1- and 2-hour values were 4.85 (0.34), 6.63 (1.73) and 5.60 (1.28) mmol/L, respectively. Early GDM was diagnosed in 209 (14.9%). In OGTT2 (n = 1067), late GDM was diagnosed in 114 (10.6%). In women without GDM (n = 953), the mean FPG values were higher and post-load values lower in OGTT1 vs. OGTT2. No interaction effects of gestational timepoint and maternal BMI on OGTT results were detected, except for the 2-hour value. In women with late GDM, both mean FPG and post-load values were lower in OGTT1 vs. OGTT2. Results were similar employing the IADPSG GDM criteria.

CONCLUSIONS

Our findings suggest that gestational-age specific OGTT thresholds for early GDM diagnosis need to be generated.

Controversies in Screening and Diagnostic Criteria for Gestational Diabetes in Early and Late Pregnancy

This review serves to evaluate the screening and diagnostic strategies for gestational diabetes and overt diabetes in pregnancy. We focus on the different early screening and diagnostic approaches in first trimester including fasting plasma glucose, random plasma glucose, oral glucose tolerance test, hemoglobin A1c, risk prediction models and biomarkers. Early screening for gestational diabetes is currently not recommended since the potential benefits and harms of early detection and subsequent treatment need to be further evaluated in randomized controlled trials.