Use of antidiabetic agents in the treatment of gestational diabetes mellitus in Germany, 2008-2012

Trends in pregnancy outcomes for women with gestational diabetes mellitus in Sweden 1998-2012: a nationwide cohort study

AIM

To assess whether incidence of maternal and neonatal outcomes for women with or without gestational diabetes mellitus (GDM) have changed over time.

METHODS

Population-based cohort study in Sweden including all singleton pregnancies over the period 1998-2012. GDM was diagnosed following Diabetic Pregnancy Study Group 1991 criteria. Poisson regression or negative binomial regression was used to model yearly relative change in numbers of cases and incidence of the outcomes with 95% confidence intervals (CI), and yearly absolute change in birthweight z-score.

RESULTS

The study included 1 455 667 pregnancies. The number of pregnancies increased over time and the overall prevalence of GDM was 1%. For women with GDM there was a significantly decreasing trend in incidence per year for large for gestational age (LGA) (0.986, 95% CI 0.975 to 0.996), birthweight z-score (-0.012, 95% CI -0.017 to -0.007) and birth trauma (0.937, 95% CI 0.907 to 0.968). The trend for small for gestational age (SGA) among women with GDM increased by an odds ratio per year (1.016, 95% CI 1.002 to 1.029). No significant interaction tests for maternal characteristics were found. Trends in outcomes for women without diabetes were similar to those for women with GDM.

CONCLUSIONS

This study shows that there were improvements in pregnancy outcomes for women with GDM between 1998 and 2012, although the incidence of SGA increased. Improvements followed similar trends in the background population. Inequalities in obstetric outcomes between women with GDM and those without have continued unchanged over 15 years, suggesting that new management strategies are required to reduce this gap.

The MTNR1B rs10830963 Variant in Interaction with Pre-Pregnancy BMI is a Pharmacogenetic Marker for the Initiation of Antenatal Insulin Therapy in Gestational Diabetes Mellitus

The rs10830963 variant of the Melatonin Receptor 1B (MTNR1B) gene is associated with the development of gestational diabetes mellitus (GDM). We hypothesized that carrying the rs10830963/G risk allele had effect on antenatal insulin therapy (AIT) initiation in GDM in a body mass index (BMI)-dependent manner. Design: In this post hoc analysis the MTNR1B rs10830963 genotype and the clinical data of 211 Caucasian GDM patients were assessed. As a first step, a pre-pregnancy BMI threshold was determined where the effect of MTNR1B rs10830963/G allele carrying on AIT initiation was the most significant using logistic regression. Maternal age adjusted real-life odds ratios (OR) values were calculated. The chi-square test was also used to calculate the p value and 10.000 bootstrap simulations were performed in each case to re-assess the statistical power and the OR. Carrying the MTNR1B rs10830963/G allele increased the odds of AIT initiation (OR = 5.2, p = 0.02 [χ² test], statistical power = 0.53) in GDM patients with pre-pregnancy BMI ≥ 29 kg/m². The statistical power reached 0.77, when the pre-pregnancy BMI cutoff of 27 kg/m² was used and the genetic effect on AIT initiation was still significant, but only using the logistic regression model. Carrying the MTNR1B rs10830963/G risk allele-in interaction with pre-pregnancy BMI-is likely be considered as a candidate pharmacogenetic marker of antenatal insulin therapy initiation and should be further assessed in precision medicine trials in GDM.

Pharmacotherapy for hyperglycemia in pregnancy - Do oral agents have a place?

Diabetes is a frequent condition in pregnancy and achieving adequate glycemic control is of paramount importance. Insulin treatment is the gold standard, oral agents are more attractive, but their safety and efficiency should be a prerequisite for their use. We have more information regarding treatment of women with gestational diabetes mellitus where glyburide can induce a picture of fetal hyperinsulinism (higher birthweight and more neonatal hypoglycemia) whereas metformin requires supplemental insulin in a larger proportion of women but achieves satisfactory perinatal outcomes with the exception of preterm birth. Information in patients with Type 2 Diabetes Mellitus is much more limited but also favors metformin. Combinations provide additional possibilities. However, as to long-term outcomes, we have no information on the impact of exposure to glyburide and it is still unclear if in utero exposure to metformin will have any effect on the offspring and the direction of this effect. Women prefer oral agents, indicating the need of additional studies.

miR-335-5p induces insulin resistance and pancreatic islet β-cell secretion in gestational diabetes mellitus mice through VASH1-mediated TGF-β signaling pathway

Multiple studies have reported different methods in treating gestational diabetes mellitus (GDM); however, the relationship between miR-335-5p and GDM still remains unclear. Here, this study explores the effect of miR-335-5p on insulin resistance and pancreatic islet β-cell secretion via activation of the TGFβ signaling pathway by downregulating VASH1 expression in GDM mice. The GDM mouse model was established and mainly treated with miR-335-5p mimic, miR-335-5p inhibitor, si-VASH1, and miR-335-5p inhibitor + si-VASH1. Oral glucose tolerance test (OGTT) was conducted to detect fasting blood glucose (FBG) fasting insulin (FINS). The OGTT was also used to calculate a homeostasis model assessment of insulin resistance (HOMA-IR). A hyperglycemic clamp was performed to measure the glucose infusion rate (GIR), which estimated β-cell function. Expressions of miR-335-5p, VASH1, TGF-β1, and c-Myc in pancreatic islet β-cells were determined by RT-qPCR, western blot analysis, and insulin release by ELISA. The miR-335-5p mimic and si-VASH1 groups showed elevated blood glucose levels, glucose area under the curve (GAUC), and HOMA-IR, but a reduced GIR and positive expression of VASH1. Overexpression of miR-335-5p and inhibition of VASH1 contributed to activated TGFβ1 pathway, higher c-Myc, and lower VASH1 expressions, in addition to downregulated insulin and insulin release levels. These findings provided evidence that miR-335-5p enhanced insulin resistance and suppressed pancreatic islet β-cell secretion by inhibiting VASH1, eventually activating the TGF-β pathway in GDM mice, which provides more clinical insight on the GDM treatment.

Patterns of glucose-lowering therapies and neonatal outcomes in the treatment of gestational diabetes in Canada, 2009-2014

AIM

To examine patterns of use of different glycaemic control agents for treating gestational diabetes mellitus.

METHODS

This was a large, retrospective, population-based cohort study of pregnant women with gestational diabetes from Alberta, Canada. We linked data from the Alberta Vital Statistics - Birth database with administrative claims data. Alberta Vital Statistics - Birth data were used to identify births that occurred between 1 January 2009 and 31 December 2014. We used International Classification of Diseases version 9/10 codes to identify women with gestational diabetes, and we excluded women with pre-existing diabetes.

RESULTS

Our cohort consisted of 16 857 women with gestational diabetes, with a total of 18 761 birth events between 2009 and 2014. Over the study period, the proportion of women with gestational diabetes who were treated with glycaemic control therapies increased from 25.0% to 31.4% (P<0.0001). The number of pregnancies treated with insulin only increased (from 23.6% to 28.3%; P<0.0001), as did the number treated with metformin, +/- insulin (from 1.4% to 3.2%; P<0.0001). Rates of large-for-gestational-age infants were significantly higher among pregnancies treated with insulin only (17%) or metformin (16.5%) than among pregnancies that did not receive any pharmacological treatment (12.8%).

CONCLUSIONS

Our findings show increasing use of insulin and metformin in women with gestational diabetes. Rates of large-for-gestational-age infants were similar among pregnant women receiving either pharmacological treatment, and higher than among pregnant women who did not receive any pharmacological treatment. Future research should explore the long-term outcomes and safety of metformin as an alternative for treating gestational diabetes.

Glibenclamide, metformin, and insulin for the treatment of gestational diabetes: a systematic review and meta-analysis

OBJECTIVE

To summarize short term outcomes in randomized controlled trials comparing glibenclamide or metformin versus insulin or versus each other in women with gestational diabetes requiring drug treatment.

DESIGN

Systematic review and meta-analysis.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Randomized controlled trials that fulfilled all the following: (1) published as full text; (2) addressed women with gestational diabetes requiring drug treatment; (3) compared glibenclamide v insulin, metformin v insulin, or metformin v glibenclamide; and (4) provided information on maternal or fetal outcomes.

DATA SOURCES

Medline, CENTRAL, and Embase were searched up to 20 May 2014.

OUTCOMES MEASURES

We considered 14 primary outcomes (6 maternal, 8 fetal) and 16 secondary (5 maternal, 11 fetal) outcomes.

RESULTS

We analyzed 15 articles, including 2509 subjects. Significant differences for primary outcomes in glibenclamide v insulin were obtained in birth weight (mean difference 109 g (95% confidence interval 35.9 to 181)), macrosomia (risk ratio 2.62 (1.35 to 5.08)), and neonatal hypoglycaemia (risk ratio 2.04 (1.30 to 3.20)). In metformin v insulin, significance was reached for maternal weight gain (mean difference -1.14 kg (-2.22 to -0.06)), gestational age at delivery (mean difference -0.16 weeks (-0.30 to -0.02)), and preterm birth (risk ratio 1.50 (1.04 to 2.16)), with a trend for neonatal hypoglycaemia (risk ratio 0.78 (0.60 to 1.01)). In metformin v glibenclamide, significance was reached for maternal weight gain (mean difference -2.06 kg (-3.98 to -0.14)), birth weight (mean difference -209 g (-314 to -104)), macrosomia (risk ratio 0.33 (0.13 to 0.81)), and large for gestational age newborn (risk ratio 0.44 (0.21 to 0.92)). Four secondary outcomes were better for metformin in metformin v insulin, and one was worse for metformin in metformin v glibenclamide. Treatment failure was higher with metformin than with glibenclamide.

CONCLUSIONS

At short term, in women with gestational diabetes requiring drug treatment, glibenclamide is clearly inferior to both insulin and metformin, while metformin (plus insulin when required) performs slightly better than insulin. According to these results, glibenclamide should not be used for the treatment of women with gestational diabetes if insulin or metformin is available.Systematic review registration NCT01998113.

Effect comparison of metformin with insulin treatment for gestational diabetes: a meta-analysis based on RCTs

PURPOSE

To compare the effects of metformin with insulin on maternal and neonatal outcomes in gestational diabetes mellitus (GDM).

METHODS

A literature search in PUBMED, EMBASE, Science Direct, Springer link, and Cochrane library was conducted using the following search terms: "Gestational Diabetes" or "GDM", and "insulin" and "metformin". Quality assessment of included studies was determined with Quality Assessment of Diagnostic Accuracy Studies. Review Manger 5.2 was used to analyze mean difference (MD)/risk ratio (RR) and 95 % confidence interval (CI) in random-effects model or fixed-effects model depending on the level of heterogeneity.

RESULTS

A total of 11 studies were identified. There was no significant difference of the effect on maternal outcomes between the two treatments in glycohemoglobin A1c levels (P = 0.37), fasting blood glucose (P = 0.66), and the incidence of preeclampsia (P = 0.26); whereas, significantly reduced results were found in the metformin group in pregnancy-induced hypertension (PIH) rate (RR = 0.53, 95 % CI 0.31-0.90, P = 0.02), average weight gains after enrollment (MD = -1.28, 95 % CI -1.54 to -1.01, P < 0.0001), and average gestational ages at delivery (MD = 0.94, 95 % CI -0.21 to -0.01, P = 0.03). Regarding neonatal outcomes, when compared with insulin group, metformin presented significantly lower average birth weights (MD = -44.35, 95 % CI -85.79 to -2.90, P = 0.04), incidence of hypoglycemia (RR = 0.69, 95 % CI 0.55-0.87, P = 0.001) and neonatal intensive care unit (NICU) (RR = 0.82, 95 % CI 0.67-0.99, P = 0.04).

CONCLUSION

Metformin can significantly reduce several adverse maternal and neonatal outcomes including PIH rate, incidence of hypoglycemia and NICU, thus it may be an effective and safe alternative or additional treatment to insulin for GDM women.