BACKGROUND AND PURPOSE:

• Meek et al. (Diabetes Care, 2021) assessed the predictive performance of HbA1C , continuous glucose monitoring (CGM) metrics and other glycemic laboratory markers to predict adverse maternal and perinatal outcomes

METHODS:

• Prespecified secondary analysis of an RCT
• Data source
  • The Continuous Glucose Monitoring in Women With Type 1 Diabetes in Pregnancy Trial (CONCEPTT Trial – See ‘Related ObG Topics’ below)
• Participants
  • Pregnant women with type 1 diabetes
• Study design
  • HbA1C, CGM data, and other biochemical markers (see below) were compared at 12, 24, and 34 weeks gestation using logistic regression and receiver operating characteristic (ROC) curves
  • Other laboratory biochemical markers: Glycated CD59 | 1,5-anhydroglucitol | Fructosamine | Glycated albumin
  • GCM metrics:
    • Mean glucose
    • Time in range (TIR) | 63 to 140 mg/dL (3.5–7.8 mmol/L)
    • Time above range (TAR): >140 mg/dL (>7.8 mmol/L)
• Primary outcomes
  • Preeclampsia
  • Preterm delivery
  • Large for gestational age
  • Neonatal hypoglycemia
  • Admission to neonatal intensive care unit

RESULTS:

• 157 women included in data analysis
• At 24 weeks
  • HbA1C, CGM metrics, and other laboratory biomarkers were all significantly associated with obstetric and neonatal outcomes
• Most CGM metrics were associated with ≥1 adverse outcome including
  • Preeclampsia | Preterm delivery | LGA | Neonatal hypoglycemia | NICU admission
• More outcomes were associated with
  • CGM metrics during the first trimester
  • Biochemical markers during the third trimester
• Some CGM metrics and laboratory markers were associated with preeclampsia at 24 weeks
• HbA1C
  • Consistent predictor of suboptimal pregnancy outcomes
  • However, not associated with preeclampsia
• The most consistently predictive CGM metrics were
  • TIR | TAR
• Area under the ROC curve for CGM, laboratory biochemical markers, and HbA1C generally did not achieve AUROCs >0.7

CONCLUSION:

• While some other laboratory biomarkers showed promise as predictors for adverse pregnancy outcomes in type 1 diabetes, they generally did not perform as well as HbA1C
• The authors conclude

HbA1c was consistently associated with pregnancy outcomes, suggesting that despite the known limitations of HbA1c for assessing antenatal glycemia, it is still a critically important biomarker for obstetric and neonatal health outcomes

While other laboratory biomarkers demonstrated some promise, none were able to significantly increase the AUROC, showing, at best, comparable prediction to HbA1c alone

Learn More – Primary Sources:

Novel Biochemical Markers of Glycemia to Predict Pregnancy Outcomes in Women With Type 1 Diabetes

Related ObG Topics:

Prepregnancy Diabetes: Does Better Glycemic Control Reduce the Risk for Adverse Events?

Does Treating Hyperglycemia Earlier in Pregnancy Improve Neonatal and Maternal Outcomes?

CONCEPTT Study: Time for Continuous Glucose Monitoring for All Pregnant Women with Type 1 Diabetes?