Comparative analysis of 2‐week glycaemic profile of healthy versus mild gestational diabetic pregnant women using flash glucose monitoring system: an observational study

Continuous Glucose Monitoring Feedback in the Subsequent Development of Gestational Diabetes: A Pilot, Randomized, Controlled Trial in Pregnant Women

OBJECTIVE

 This study evaluated the effects of receiving glucose feedback from continuous glucose monitoring (CGM) by intermittent scanning (unblinded group), and CGM with masked feedback (blinded group) in the subsequent development of gestational diabetes mellitus (GDM).

STUDY DESIGN

 This was a prospective, single-center, pilot, randomized controlled trial including n = 206 pregnant women in the first trimester of pregnancy with no prior diagnosis of type 1 or type 2 diabetes. The participants were randomized into the unblinded group or blinded group and wore the CGM in the first trimester of pregnancy (9-13 weeks), the second trimester of pregnancy (18-23 weeks), and late-second to early-third trimester (24-31 weeks). The primary outcome was GDM rate as diagnosed by the 75-g oral glucose tolerance test (OGTT) at 24 to 28 weeks.

RESULTS

 Over 47 months, 206 pregnant women were enrolled at 9 to 13 weeks. The unblinded group had a higher prevalence of women who developed GDM (21.5 vs. 14.9%; p > 0.05), compared to the blinded group. In the unblinded group compared to the blinded group, plasma glucose values were higher at 1 hour (median 7.7 [interquartile range {IQR}: 6.3-9.2] vs. 7.5 [6.3-8.7]) and 2 hours (6.3 [5.8-7.7] vs. 6.2 [5.3-7.2]), but lower at 0 hour (4.2 [4.0-4.5] vs. 4.3 [4.1-4.6]; p > 0.05). All these differences were not statistically significant.

CONCLUSION

 Glucose feedback from CGM wear in the first to the third trimester of pregnancy without personalized patient education failed to alter GDM rate.

KEY POINTS

· Continuous glucose monitoring (CGM) is feasible for use in pregnant women.. · No significant difference in gestational diabetes rates with or without CGM feedback.. · Future clinical trials should incorporate CGM education and personalized guidance to enhance study outcomes..

Glycaemia dynamics in gestational diabetes mellitus

Pregnant women may develop gestational diabetes mellitus (GDM), a disease of pregnancy characterised by maternal and fetal hyperglycaemia with hazardous consequences to the mother, the fetus, and the newborn. Maternal hyperglycaemia in GDM results in fetoplacental endothelial dysfunction. GDM-harmful effects result from chronic and short periods of hyperglycaemia. Thus, it is determinant to keep glycaemia within physiological ranges avoiding short but repetitive periods of hyper or hypoglycaemia. The variation of glycaemia over time is defined as 'glycaemia dynamics'. The latter concept regards with a variety of mechanisms and environmental conditions leading to blood glucose handling. In this review we summarized the different metrics for glycaemia dynamics derived from quantitative, plane distribution, amplitude, score values, variability estimation, and time series analysis. The potential application of the derived metrics from self-monitoring of blood glucose (SMBG) and continuous glucose monitoring (CGM) in the potential alterations of pregnancy outcome in GDM are discussed.

Glycemic Variability in Early Pregnancy May Predict a Subsequent Diagnosis of Gestational Diabetes

PURPOSE

This study examined the prospective association between CGM-derived glycemic variability (GV) and glycemic control (GC) parameters in the first and second trimester, with subsequent diagnosis of GDM in the early third trimester.

METHODS

In a longitudinal observational study, 60 study participants in the first trimester (9-13 weeks' gestation), and 53 participants (18-23 weeks' gestation) in the second trimester of pregnancy had CGM data extracted after a minimum of 8 days' wear time (up to 14 days). At 24-31 weeks' gestation, participants underwent a 75 g, 2-hour oral glucose-tolerance test as per IADPSG criteria to diagnose GDM. GV parameters examined in both first and second trimesters were mean amplitude of glycemic excursion (MAGE), standard deviation (SD), mean glucose, and coefficient of variation (CV). GC parameters measured were J-Index and percentage of time spent in glucose target ranges.

RESULTS

The first trimester SD and MAGE were significantly higher in participants subsequently diagnosed with GDM (SD adjusted median 1.31 [interquartile range 1.2-1.3] mmol/L; MAGE 3.26 [3.2-3.3] mmol/L) than those who were not (SD 1.01 [0.9-1.0] mmol/L, MAGE 2.59 [2.4-2.6] mmol/L; p<0.05). Similarly, second trimester SD and MAGE were also significantly higher in participants subsequently diagnosed with GDM (SD 1.35 [1.3-1.4] mmol/L; MAGE 3.32 (3.31-3.41) mmol/L) than those who were not (SD 0.99 [0.98-1.01] mmol/L, MAGE 2.42 [2.42-2.55] mmol/L; p<0.05). Associations between SD and MAGE with GDM outcomes were adjusted for prepregnancy BMI and ethnicity. There were nonsignificant trends of higher J-Index scores in the first and second trimester, higher CV in the first trimester only, and higher mean in the second trimester only in participants diagnosed with GDM. Other study parameters measured were not significantly different between groups (p>0.003).

CONCLUSION

Our study suggests the potential value of CGM-derived SD and MAGE in early pregnancy as potential predictors of subsequent GDM diagnosis.

Comparing the Efficacies of Telemedicine and Standard Prenatal Care on Blood Glucose Control in Women With Gestational Diabetes Mellitus: Randomized Controlled Trial

BACKGROUND

Gestational diabetes mellitus (GDM) can usually be well controlled by health education and lifestyle management, resulting in better pregnancy outcomes. However, standard clinical prenatal care, which consists of clinic visits every 2 weeks, may not provide sufficient management for women with GDM. Telemedicine demonstrates a potential to fill this gap.

OBJECTIVE

The objective of this study was to investigate whether health education and lifestyle management delivered through a WeChat group chat was more effective in controlling blood glucose (BG) than standard clinical prenatal care among women with GDM.

METHODS

In this multicenter randomized controlled trial, women with GDM diagnosed by an oral glucose tolerance test between 23 and 30 (+6) gestational weeks were randomized to a WeChat group chat-based BG management group or a routine clinical prenatal care group. The primary outcome was the change in the glycemic qualification rate during the follow-up period in both groups. The secondary outcomes were pregnancy outcomes.

RESULTS

A total of 309 women with GDM participated in the trial, with 162 women randomized to the control group and 147 to the intervention group. No significant differences in baseline characteristics were found between the control and intervention groups. Participants were further divided into 4 groups according to gestational weeks at enrollment for further analysis. The glycemic qualification rate of the intervention group was higher than that of the control group at nearly all time points in Groups 1 to 3, among which 3 time points reached statistical significance: Group 1 at T3 (54.8% vs 83.3%) and Group 2 at T3 (62.5% vs 80.0%) and T7 (75.0% vs 100%). The glycemic qualification rate gradually increased as gestational weeks progressed in both groups, regardless of the intervention method. None of the pregnancy outcomes measured, including delivery mode, premature rupture of the membranes, preterm birth, infant's birth weight, and postpartum hemorrhage, were significantly different between the control and intervention groups.

CONCLUSIONS

This multicenter randomized controlled trial that assessed women with noninsulin-dependent GDM demonstrated that additional instant messaging platforms, such as WeChat, used for health education and lifestyle intervention in China tend to be more effective for BG control than standard clinical prenatal care alone.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03748576; https://clinicaltrials.gov/ct2/show/NCT03748576.

A comparison of meal tolerance test and oral glucose tolerance test for predicting insulin therapy in patients with gestational diabetes

Aims

To identify factors predicting a need for insulin therapy in gestational diabetes mellitus (GDM) by comparing plasma glucose (PG) levels in a 75-g oral glucose tolerance test (75-g OGTT) with those in a 500-kcal meal tolerance test (MTT) containing 75 g of carbohydrate.

Subjects and methods

The MTT was performed in 61 patients who diagnosed with GDM by a 75-g OGTT (age, 33.2 ± 4.5 years; prepregnancy body mass index, 22.6 ± 4.7 kg/m²; number of gestational weeks, 25.1 ± 6.4 weeks). PG and serum insulin levels were measured before the meal and up to 180 min after the meal. The insulin secretion capacity and resistance index were calculated.

Results

PG levels increased from 86.8 ± 8.8 mg/dL at fasting to 132.7 ± 20.1 mg/dL at 30 min, and 137.8 ± 27.7 mg/dL at 60 min after MTT in the 35 patients with needed insulin therapy; these levels were significantly higher than those in the 26 patients, who only needed diet therapy. The patients with needed insulin therapy had significantly higher fasting PG levels in the 75-g OGTT, PG levels at fasting and 30 min after the MTT, and homeostasis model assessment of insulin resistance (HOMA-IR), and a significantly lower disposition index (DI) and insulin index than patients treated by diet alone. Receiver operating characteristic curve analysis was performed for factors involved in insulin therapy, with the following cutoff values: fasting PG in the 75-g OGTT, 92 mg/dL; PG 30 min after MTT, 129 mg/dL; HOMA-IR, 1.51; DI, 3.9; HbA1c, 5.4%. Multivariate analysis revealed that the 30-min PG level after MTT and HOMA-IR predicted insulin therapy.

Conclusion

PG levels at 30 min after MTT may be useful for identifying patients with GDM, who need insulin therapy.

Adiponectin DNA methylation in South African women with gestational diabetes mellitus: Effects of HIV infection

DNA methylation is increasingly recognized as a potential biomarker of metabolic disease. However, there is limited information on the impact of human immunodeficiency virus (HIV) infection on the candidacy of DNA methylation to serve as molecular biomarkers. This study investigated the effect of HIV infection on DNA methylation patterns in the peripheral blood of South African women with (n = 95) or without (n = 191) gestational diabetes mellitus (GDM). DNA methylation levels at eight CpG sites in the adiponectin gene (ADIPOQ) promoter were measured using bisulfite conversion and pyrosequencing. Differences between HIV negative (^-) and positive (⁺) women were observed. In HIV^- women, methylation at CpG -3400 was lower in GDM⁺ women compared to those with normoglycemia (8.5-fold; p = 0.004), and was associated with higher fasting glucose (β-co-efficient = 0.973; p = 0.006) and lower adiponectin (β-co-efficient = -0.057; p = 0.014) concentrations. These associations were not observed in HIV⁺ women. In silico analysis showed that Transcription Factor AP2-alpha is able to bind to the altered CpG site, suggesting that CpG -3400 may play a functional role in the regulation of ADIPOQ expression. Our findings show that DNA methylation differs by HIV status, suggesting that HIV infection needs to be taken into consideration in studies exploring DNA methylation as a biomarker of GDM in high HIV prevalence settings.

Glycemic qualification rate and frequency of self-monitoring blood glucose glycemic qualification rate and frequency of self-monitoring blood glucose (SMBG) in women with gestational diabetes mellitus (GDM)

AIMS

To explore the relationship between blood glucose (BG) control rate and self-monitoring blood glucose (SMBG) compliance of women with gestational diabetes mellitus (GDM).

METHODS

Women with GDM (n = 309) were randomized to receive routine clinical prenatal care or additional online management. Follow-up visits were conducted every two weeks (noted here as T) from enrollment to delivery. SMBG records were used for the analysis.

RESULTS

Both the intervention group and the control group had an increasing BG control rate and decreasing SMBG compliance during the whole follow-up period. Detailed data analysis on separate follow-up periods showed that the SMBG frequency was negatively correlated with the BG control rate in most Ts and that the BG control rate of T_n-1 was negatively correlated with the SMBG frequency of T_n in the adjacent T. Only in the intervention group was T₂ SMBG compliance not under the influence of the T₁ BG control rate.

CONCLUSIONS

Our data suggested that regardless of management approach, the BG control rate increased, and the SMBG frequency decreased as gestational weeks increased in women with GDM. Even in separate follow-up periods, the SMBG frequency was negatively correlated with the BG control rate both within one follow-up period and between two adjacent follow-up periods.

A Review of Research Progress on Glycemic Variability and Gestational Diabetes

Gestational diabetes mellitus (GDM) is associated with many adverse obstetric outcomes and neonatal outcomes, including preeclampsia, Cesarean section, and macrosomia. Active screening and early diabetes control can reduce the occurrence of adverse outcomes. Glycosylated hemoglobin (HbA1c) only reflects average blood glucose levels, but not glycemic variability (GV). Studies have shown that GV can cause a series of adverse reactions, and good control of GV can reduce the incidence of adverse pregnancy outcomes in patients with GDM. In order to provide clinicians with a better basis for diagnosis and treatment, this study reviewed the measurement, evaluation, and control of GV, the importance of GV for patients with GDM, and correlations between GV and maternal and neonatal outcomes.