In a randomized controlled trial of patients with gestational diabetes diagnosed between eight and 26 weeks’ gestation, continuous glucose monitoring did not improve the primary endpoint of time in range vs self-monitoring of blood glucose, but it was associated with better maternal and neonatal outcomes.
In the Steady Sugar trial, researchers enrolled 128 patients at a single center and analyzed 120 who completed the study. Patients were randomized in a 2:1 ratio to real-time continuous glucose monitoring or Secondary outcomes favored CGM, including fewer preterm births and neonatal intensive care unit admissions., indicating smaller infants.
Time in range, defined as 63 to 140 mg/dL, was similar between groups at 89% in the continuous glucose monitoring group and 87% in the control group. Mean glucose, time above range, and time below range also were not statistically significantly different.
Even so, several maternal outcomes favored continuous glucose monitoring. Failed induction leading to cesarean delivery occurred in 20% of the continuous glucose monitoring group vs 44% of the control group. Patients in the continuous glucose monitoring group also delivered later, at 38 vs 37 weeks, and had lower rates of preterm delivery, 7% vs 18%.
Neonatal outcomes also favored continuous glucose monitoring. Large-for-gestational-age birth occurred in 5% of the continuous glucose monitoring group vs 18% of controls, and neonatal intensive care unit admission occurred in 23% vs 45%, respectively. Neonatal hypoglycemia was numerically lower with continuous glucose monitoring, 46% vs 65%, but the difference was not statistically significant.
The investigators also found that continuous glucose monitoring identified more hyperglycemic episodes per week than self-monitoring of blood glucose, likely reflecting more complete detection of glycemic excursions with continuous monitoring. Across the full cohort, higher mean glucose, greater glucose variability, and more time above range were associated with earlier delivery and higher birth-weight centiles, while higher time in range was associated with later gestational age at birth and lower birth-weight centiles, indicating smaller infants.
Patients reported high satisfaction with continuous glucose monitoring, with a mean benefit score of 4.3 out of 5. The highest-rated items reflected improved understanding of how eating and daily habits affect glucose levels.
The researchers noted important limitations, including the single-center design, possible underpowering for the primary endpoint, and the absence of a true standard-of-care control group because control patients also underwent blinded continuous glucose monitoring and had treatment informed by those data.
A subsequent correction to Table 3 addressed typographical errors but did not alter the key maternal and neonatal outcome findings highlighted in the trial report.
“Despite no improvement in TIR, CGM improved maternal and neonatal outcomes,” wrote lead study author Karen Elkind-Hirsch, PhD, of Woman’s Hospital in Baton Rouge, Louisiana, and Dexcom in San Diego, and colleagues.
The study was funded by Dexcom, which also supplied the devices. Several researchers were Dexcom employees and assisted with the writing and submission of the manuscript. Elkind-Hirsch reported grant support from Dexcom and Novo Nordisk and advisory roles with Eli Lilly and Novo Nordisk. No other relevant conflicts were reported.
Source: Diabetes, Obesity and Metabolism