Self-monitoring of blood glucose two-weekly versus weekly in gestational diabetes on nutrition therapy: A randomized trial

Abstract

Objective: To evaluate 4-point per day self-monitoring of blood glucose (SMBG) every 2 weeks compared with every week.

Methods: A total of 104 patients with lifestyle-controlled gestational diabetes (GDMA1) were randomized to 2-weekly or weekly 4-point per day (fasting on awakening and 2-h post-meals) SMBG. Primary outcome was the change in glycated hemoglobin (HbA1c) level from enrollment to 36 weeks of pregnancy across trial arms. The non-inferiority margin was an HbA1c increase of 0.2%.

Results: The mean difference for change in HbA1c from enrollment to 36 weeks was 0.003% (95% confidence interval [CI] -0.098% to +0.093%), within the 0.2% non-inferiority margin. The change in HbA1c level increased significantly within both trial arms-0.275% ± 0.241% (P < 0.001) in 2-weekly arm versus 0.277% ± 0.236% (P < 0.001) in the weekly arm. Participants randomized to 2-weekly SMBG were significantly less likely to receive anti-glycemic treatment-5/52 (9.6%) versus 14/50 (28.0%) (relative risk 0.34, 95% CI 0.13-0.88; P = 0.017). All secondary outcomes-maternal weight gain, preterm delivery, cesarean delivery, birthweight, and neonatal admission-were not significantly different.

Conclusions: In GDMA1, 2-weekly is non-inferior to weekly SMBG on the change in HbA1c level. Two-weekly SMBG appeared to be adequate for monitoring women with GDMA1.

Clinical trial registration: This study was registered in ISRCTN registry on March 25, 2022 with trial identification number: ISRCTN13404790 (https://doi.org/10.1186/ISRCTN13404790). The first participant was recruited on April 12, 2022.

Keywords: HbA1c; blood sugar profile; cesarean delivery; diet; gestational diabetes; glycated hemoglobin; self-monitoring blood glucose.