The Utility of Lower Glycemic Targets for Treating Gestational Diabetes: A Retrospective Study.

OBJECTIVE: In vivo study of glucose homeostasis in pregnancy suggests normal glucose levels are lower than current glycemic targets used in gestational diabetes. After the HAPO study results, our institution began using glycemic targets of fasting 85 mg/dL and 2-hour postprandial of 110 mg/dL. We reviewed our results. METHODS: A retrospective cohort of GDM patients that delivered at KUMC from January 2007 to May 2017 was reviewed. All patients were diagnosed with the 2-step Carpenter-Coustan thresholds. High targets were compared with low targets. The primary outcome investigated was birthweight > 90% (large for gestational age, LGA). RESULTS: 604 patients were studied, and 34% were treated with low glycemic targets. Our unadjusted results showed that the low-target group had a lower incidence of LGA infants (24.0 vs. 31.8%), higher incidence of neonatal hypoglycemia (20.7 vs. 11.6%), and inductions (39.4 vs. 20.5%). After adjustment for demographic variables, only a higher risk of inductions remained (aOR 2.54 (1.44, 4.49)). CONCLUSION: Lower glycemic targets did not produce large reductions in fetal overgrowth, but they were associated with a higher rate of inductions. As there were no observed differences in maternal or neonatal outcomes otherwise, aiming for lower glycemic targets in GDM is likely not cost-effective.

A retrospective study comparing outcomes in a midwestern US population after introduction of IADPSG guidelines for gestational diabetes.

OBJECTIVE: More evidence is required to endorse the 1-step approach for gestational diabetes mellitus (GDM) for clinical practice. Since 2010, our department has pragmatically allowed faculty to self-select the guidelines they use to screen and diagnose GDM. We sought to compare the maternal and neonatal outcomes from these two simultaneous cohorts. STUDY DESIGN: We performed a retrospective cohort study of all singleton pregnancies delivered between October 2011 and -November 2013 at our hospital. Patients were excluded if they had preexisting diabetes, were not screened or screened inappropriately, or their fetus had congenital anomalies. Patients were grouped by their screening strategy, and maternal and neonatal outcomes were analyzed. RESULTS: The 1-step group had a higher incidence of GDM (21.6% versus 5.0%). Initial results suggested higher rates of neonatal hypoglycemia, phototherapy for hyperbilirubinemia, and a lower rate of gestational HTN. After adjustment, these differences disappeared, but a lower rate of large for gestational age (LGA) infants was discovered (adjusted odds ratios (aOR) 0.78). CONCLUSION: The picture remains unclear as to whether the 1-step approach is associated with significantly improved outcomes compared with the 2-step approach. We did find a lower risk for a LGA infant in our 1-step cohort, but it is unlikely that the 1-step approach would be cost-effective due to the absence of other improved outcomes.