Hyperglycemia in pregnancy: prevalence, impact, and management challenges

Gestational Diabetes: Glycemic Control in the Last Two Weeks Before Delivery Contributes to Newborn Insulinemia

INTRODUCTION

Fetal hyperinsulinemia in gestational diabetes mellitus (GDM) not only is important during intrauterine life, a time when it can result in macrosomia, but also at delivery, since it can result in neonatal hypoglycemia and hyperbilirubinemia. The question is, how long before delivery does maternal glycemic control contribute to newborn insulinemia in GDM?

METHODS

In 72 women with GDM, we calculated Spearman's rank (r_s) correlations between umbilical cord blood C-peptide at birth (a biomarker of insulin secretion), and both maternal glycosylated hemoglobin (HbA1c) and mean blood glucose (MBG) recorded in the last two visits prior to delivery. Iterative correlations were done between umbilical cord blood C-peptide at birth, and maternal glucose control, at 0, 1, 2, 3, 4, and 5 weeks before delivery.

RESULTS

At an early visit (32.95 ± 1.8 weeks), r_s = 0.353 (P = 0.07) between HbA1c and C-peptide, whereas r_s = 0.244 (P = 0.186) between MBG and C-peptide. At the latest visit (35.04 ± 1.6 weeks), r_s = 0.456 (P = 0.004) between HbA1c versus C-peptide, and r_s = 0.359 (P = 0.023) between MBG versus C-peptide. Iterative correlations between MBG and C-peptide became significant at 2 weeks before delivery.

CONCLUSION

To further reduce the risk of hypoglycemia and hyperbilirubinemia in infants born to women with GDM, besides applying a strict in-patient glucose control protocol at delivery, it is necessary to improve even more the quality of maternal glucose control during the last 2 weeks prior to delivery.

A mouse model of gestational glucose intolerance through exposure to a low protein diet during fetal and neonatal development

KEY POINTS

Pancreatic β-cell dysfunction is hypothesized to be the significant determinant of gestational diabetes pathogenesis, however pancreatic samples from patients are scarce. This study reports a novel mouse model of gestational glucose intolerance in pregnancy, originating from previous nutrition restriction in utero, in which glucose intolerance was restricted to late gestation as is seen in human gestational diabetes. Glucose intolerance was attributed to reduced β-cell proliferation, leading to impaired gestational β-cell mass expansion in maternal endocrine pancreas, in addition to reduced glucose-stimulated insulin secretion. This model reproduces some of the features of gestational diabetes and is suitable for testing safe therapeutic interventions that increase β-cell mass during pregnancy and prevent or reverse gestational glucose intolerance.

ABSTRACT

Gestational diabetes mellitus (GDM) is an increasingly prevalent form of diabetes that appears during pregnancy. Pathological studies link a failure to adaptively increase maternal pancreatic β-cell mass (BCM) in pregnancy to GDM. Due to the scarcity of pancreatic samples from GDM patients, we sought to develop a novel mouse model for impaired gestational glucose tolerance. Mature female C57Bl/6 mouse offspring (F1) born to dams fed either a control (C) or low-protein (LP) diet during gestation and lactation were randomly allocated into two subsequent study groups: pregnant (CP, LPP) or non-pregnant (CNP, LPNP). Glucose tolerance tests were performed at gestational day (GD) 9, 12 and 18. Subsequently, pancreata were removed for fluorescence immunohistochemistry to assess α-cell mass (ACM), BCM and β-cell proliferation. An additional group of animals was used to measure insulin secretion from isolated islets at GD18. LPP females displayed glucose intolerance compared to CP females at GD18 (P < 0.001). BCM increased threefold at GD18 in CP females. However, LPP females had reduced BCM expansion (P < 0.01) concurrent with reduced β-cell proliferation at GD12 (P < 0.05). LPP females also had reduced ACM expansion at GD18 (P < 0.01). LPP islets had impaired glucose-stimulated insulin secretion in vitro compared to CP islets (P < 0.01). Therefore, impaired glucose tolerance during pregnancy is associated with a failure to adequately adapt BCM, as a result of reduced β-cell proliferation, in addition to lower glucose-stimulated insulin secretion. This model could be used to evaluate novel interventions during pregnancy to increase BCM or function as a strategy to prevent/reverse GDM.

Orthosiphon stamineus as a potential antidiabetic drug in maternal hyperglycemia in streptozotocin-induced diabetic rats

Background

Maternal hyperglycemia is associated with increased risk of adverse outcomes for both mother and offspring. Insulin is the standard treatment of hyperglycemia with the aim to reduce risks of complications, however, due to several restrictions, the search for more effective drugs from traditional medicinal plants continues.

Methods

The antidiabetic effects of Orthosiphon stamineus (O . stamineus ) in non-pregnant and pregnant streptozotocin-induced Sprague Dawley rats were identified. The effect of different concentrations of O. stamineouson insulin level using isolated pancreatic islets in response to low and high concentrations of glucose was identified. Oral glucose tolerance test was performed in both pregnant and non-pregnant rats prior to and after treatment with O. stamineus (0.1 g/100 g of body weight). O. stamineus was given orally daily for 2 weeks in non-pregnant and 10 days in pregnant rats.

Results

Oral glucose tolerance test indicated that treatment with O. stamineus in non-pregnant and pregnant rats significantly reduced blood glucose level and stimulated glucose-induced insulin secretion. No mortality was recorded throughout the study and no signs of toxicity during the experimental period including in both mother and foetus. For plasma analysis, the interactions of peptides such as GLP-1 and ghrelin level might contribute to the glucose lowering effect by O. stamineus via stimulation of insulin. The incubation of islets showed that O . stamineussignificantly stimulated insulin release in response to high glucose.

Conclusion

O. stamineus could be a potential source of a specific oral hypoglycaemic agent to treat glucose intolerance in pregnancy.

Effect of gestational weight gain on insulin resistance mediated by serum adipokine concentrations in advanced maternal age

INTRODUCTION

With the implementation of the universal two-child policy, the number of pregnant women of advanced maternal age (AMA) will increase steadily. We aimed to investigate whether the effect of gestational weight gain on insulin resistance (IR) before delivery was mediated by serum adipokine concentrations in AMA.

MATERIAL AND METHODS

This cross-sectional study included 80 pregnant women of AMA recruited consecutively before delivery from the Department of Obstetrics and Gynecology between August 2016 and July 2017. At delivery, maternal weight during the third trimester was recorded and serum adipokines were measured. IR was calculated using the homeostasis model assessment 2 (HOMA2) method.

RESULTS

Weight gain (WG) during the third trimester was positively associated with serum leptin concentrations (r = 0.34, p = 0.0018) and HOMA-IR indices (r = 0.25, p = 0.025), but not related with serum concentration of adiponectin (r = 0.12, p = 0.28). WG during the third trimester and serum concentration of leptin were independently associated with the level of HOMA-IR by multivariate analysis. Subsequently, according to mediation analysis, the association between WG during the third trimester and HOMA-IR mediated by serum leptin concentrations was statistically significant (z = 1.588, p < 0.05).

CONCLUSIONS

Taken together, our findings suggest that the relationship between WG during the third trimester and IR was mediated by serum leptin concentrations in AMA, but not serum adiponectin concentrations.

Metformin-treated-GDM has lower risk of macrosomia compared to diet-treated GDM- a retrospective cohort study

Background: The diagnosis of gestational diabetes (GDM) has undergone several revisions. The broad adoption of the 2013 WHO criteria for hyperglycemia in pregnancy has increased the prevalence of GDM with no apparent benefit on pregnancy outcomes. The study aims to investigate the pregnancy outcomes in women with GDM diagnosed based on the WHO criteria compared to a control group; the impact of other confounders; and the difference in outcomes between GDM women who needed pharmacotherapy (GDM-T) and those who did not (GDM-D).Methods: This is a retrospective cohort study that included GDM women compared to normoglycemic controls between March 2015 and December 2016 in the Women's Hospital, Qatar.Results: The study included 2221 women; of which 1420 were normoglycemic, and 801 were GDM (358 GDM-D and 443 GDM-T). At conception, GDM women were older (mean age 32.5 ± 5.4 versus 29.6 ± 5.6 years, p<.001) and had higher prepregnancy BMI (mean BMI 32.2 ± 6.2 versus 28.2 ± 6.1 kg/m2, p<.01) compared to the controls, respectively. After correction for age, prepregnancy weight, and gestational weight gain (GWG); women with GDM had a higher risk of preterm labor (OR: 1.72; 95% CI: 1.32-2.23), large for gestational age (GA) (OR: 1.67; 95% CI: 1.22-2.29), neonatal ICU admission (OR: 1.57; 95% CI: 1.15-2.13), and neonatal hypoglycemia (OR: 3.22; 95% CI: 2.06-5.03). At conception, GDM-T women were older (mean age 33.3 ± 5.0 versus 31.5 ± 5.7 years, p<.001) and had higher BMI (mean BMI 32.9 ± 6.3 versus 231.2 ± 6.0 kg/m2, p=.01) compared to GDM-D, respectively. Metformin was used in 90.7% of the GDM-T women. Women in the GDM-T group had lower GWG/week compared to GDM-D (-0.01 ± 0.7 versus 0.21 ± 0.5 kg/week; p<.001). After correcting for age, prepregnancy weight and GWG; GDM-T had a higher risk of preterm labor (OR: 1.66; 95% CI: 1.20-2.22), and C-section (OR: 1.37, 95% CI: 1.02-1.85) and reduced risk of macrosomia (OR: 0.56; 95% CI: 0.32-0.96) and neonatal hypoglycemia (OR: 0.49; 95% CI: 0.28-0.82).Conclusion: In addition to hyperglycemia, the adverse effects of GDM on pregnancy outcomes are multifactorial and includes maternal age, maternal obesity, and gestational weight gain. Treatment with metformin reduces maternal weight gain, the risk of macrosomia and neonatal hypoglycemia compared to diet alone.

Improving Uptake of Postnatal Checking of Blood Glucose in Women Who Had Gestational Diabetes Mellitus in Universal Healthcare Settings: A Systematic Review

The aim of this systematic review is to look at the barriers to uptake and interventions to improve uptake of postnatal screening in women who have had gestational diabetes mellitus (GDM). Increasing postnatal screening rates could lead to timely interventions that could reduce the incidence of type 2 diabetes mellitus (T2DM), the associated long-term health complications, and the financial burden of T2DM. A systematic review of the literature was undertaken. PubMed, Embase, Medline, CINAHL and the Cochrane library databases were searched using well-defined search terms. Predefined inclusion and exclusion criteria were used to identify relevant manuscripts. Data extractions and quality assessments were performed by one reviewer and checked by a second reviewer. Eleven primary studies of various research design and three systematic reviews were included. We identified seven themes within these studies and these were described in two categories, barriers and interventions. There appeared to be no single intervention that would overcome all the identified barriers, however, reminders to women and healthcare professionals appear to be most effective. Uptake rates of testing for T2DM are low in women with GDM. Interventions developed with consideration of the identified barriers to uptake could promote greater numbers of women attending for follow-up.

Genetic Variants in Preeclampsia: Lessons From Studies in Latin-American Populations

Placental vascularization is a tightly regulated physiological process in which the maternal immune system plays a fundamental role. Vascularization of the maternal-placental interface involves a wide range of mechanisms primarily orchestrated by the fetal extravillous trophoblast and maternal immune cells. In a healthy pregnancy, an immune cross-talk between the mother and fetal cells results in the secretion of immunomodulatory mediators, apoptosis of specific cells, cellular differentiation/proliferation, angiogenesis, and vasculogenesis, altogether favoring a suitable microenvironment for the developing embryo. In the context of vasculopathy underlying common pregnancy disorders, it is believed that inefficient invasion of extravillous trophoblast cells in the endometrium leads to a poor placental blood supply, which, in turn, leads to decreased secretion of angiogenic factors, hypoxia, and inflammation commonly associated with preterm delivery, intrauterine growth restriction, and preeclampsia. In this review, we will focus on studies published by Latin American research groups, providing an extensive review of the role of genetic variants from candidate genes involved in a broad spectrum of biological processes underlying the pathophysiology of preeclampsia. In addition, we will discuss how these studies contribute to fill gaps in the current understanding of preeclampsia. Finally, we discuss some trending topics from important fields associated with pregnancy vascular disorders (e.g., epigenetics, transplantation biology, and non-coding RNAs) and underscore their possible implications in the pathophysiology of preeclampsia. As a result, these efforts are expected to give an overview of the extent of scientific research produced in Latin America and encourage multicentric collaborations by highlighted regional research groups involved in preeclampsia investigation.

Programming of Vascular Dysfunction in the Intrauterine Milieu of Diabetic Pregnancies

With the rising global tide of obesity, gestational diabetes mellitus (GDM) burgeoned into one of the most common antenatal disorders worldwide. Macrosomic babies born to diabetic mothers are more likely to develop risk factors for cardiovascular disease (CVD) before they reach adulthood. Rodent studies in offspring born to hyperglycemic pregnancies show vascular dysfunction characterized by impaired nitric oxide (NO)-mediated vasodilation and increased production of contractile prostanoids by cyclooxygenase 2 (COX-2). Vascular dysfunction is a key pathogenic event in the progression of diabetes-related vascular disease, primarily attributable to glucotoxicity. Therefore, glucose-induced vascular injury may stem directly from the hyperglycemic intrauterine environment of GDM pregnancy, as evinced by studies showing endothelial activation and inflammation at birth or in childhood in offspring born to GDM mothers. This review discusses potential mechanisms by which intrauterine hyperglycemia programs dysfunction in the developing vasculature.

NICU Admissions After a Policy to Eliminate Elective Early Term Deliveries Before 39 Weeks' Gestation

BACKGROUND AND OBJECTIVES

Early term infants (37-<39 weeks' gestation) are at higher risk of adverse outcomes than term infants (39-<41 weeks' gestation). We hypothesized that a policy to eliminate elective, early term deliveries would result in fewer NICU admissions and shorter lengths of stay among infants born ≥37 weeks.

METHODS

This was a retrospective cohort study of singleton infants born ≥37 weeks at a tertiary medical center from 2004 to 2015 (preperiod: 2004-2008; postperiod: 2010-2015; washout period: 2009). We compared the incidence of early term delivery, NICU admissions (short: ≥4-<24 hours, long: ≥24 hours), NICU diagnoses, and stillbirths in both periods. We used modified Poisson regression to calculate adjusted risk ratios.

RESULTS

There were 20 708 and 24 897 singleton infants born ≥37 weeks in the pre- and postperiod, respectively. The proportion of early term infants decreased from 32.5% to 25.7% (P < .0001). NICU admissions decreased nonsignificantly (9.2% to 8.8%; P = .22), with a significant reduction in short NICU stays (5.4% to 4.6%; adjusted risk ratio: 0.85 [95% confidence interval: 0.79-0.93]). Long NICU stays increased slightly (3.8% to 4.2%), a result that was nullified by adjusting for neonatal hypoglycemia. A nonsignificant increase in the incidence of stillbirths ≥37 to <40 weeks was present in the postperiod (7.5 to 10 per 10 000 births; P = .46).

CONCLUSIONS

Reducing early term deliveries was associated with fewer short NICU stays, suggesting that efforts to discourage early term deliveries in uncomplicated pregnancies may minimize mother-infant separation in the newborn period.

Poor Sleep Quality Is Associated with Higher Hemoglobin A1c in Pregnant Women: A Pilot Observational Study

We hypothesized that poor sleep quality exacerbates glucose intolerance manifested as elevated glycosylated hemoglobin (HbA1c), which increases the risk for gestational diabetes. To test this, 38 pregnant and 22 non-pregnant (age, 18–35 years; body-mass index, 20–35 kg/m²) otherwise healthy women were enrolled in the study. Sleep quality was assessed during gestational week 24 (pregnant), or outside of the menstrual period (non-pregnant), using qualitative (Pittsburgh Sleep Quality Index) and objective (actigraphic wrist-watch) measures. Blood glucose, total cortisol, and depression status were evaluated. Eight pregnant and one non-pregnant women were lost to follow-up, or withdrew from the study. There was a higher incidence of poor sleep quality in pregnant (73%) relative to non-pregnant women (43%). Although actigraphic data revealed no differences in actual sleep hours between pregnant and non-pregnant women, the number of wake episodes and sleep fragmentation were higher in pregnant women. Poor sleep quality was positively correlated with higher HbA1c in both pregnant (r = 0.46, n = 26, p = 0.0151) and non-pregnant women (r = 0.50, n = 19, p = 0.0217), reflecting higher average blood glucose concentrations. In contrast, poor sleep was negatively correlated with cortisol responses in pregnant women (r = −0.46, n = 25, p = 0.0167). Three pregnant women had elevated one-hour oral glucose tolerance test results (>153 mg/dL glucose). These same pregnant women exhibited poor sleep quality. These results support the suggestion that poor sleep quality is an important risk factor that is associated with glucose intolerance and attendant health complications in pregnancy.

Prevalence of newly detected diabetes in pregnancy in Qatar, using universal screening

Background

Diabetes first detected during pregnancy is currently divided into gestational diabetes mellitus (GDM) and diabetes mellitus (DM)- most of which are type 2 DM (T2DM). This study aims to define the prevalence and outcomes of diabetes first detected in pregnancy based on 75-gram oral glucose tolerance test (OGTT)using the recent WHO/IADPSG guidelines in a high-risk population.

Methods

This is a retrospective study that included all patients who underwent a 75 g (OGTT) between Jan 2016 and Apr 2016 and excluded patients with known pre-conception diabetes.

Results

The overall prevalence of newly detected diabetes in pregnancy among the 2000 patients who fulfilled the inclusion/exclusion criteria was 24.0% (95% CI 22.1–25.9) of which T2DM was 2.5% (95% CI 1.9–3.3), and GDM was 21.5% (95% CI 19.7–23.3). The prevalence of newly detected diabetes in pregnancy was similar among the different ethnic groups.

The T2DM group was older (mean age in years was 34 ±5.7 vs 31.7±5.7 vs 29.7 ±5.7, p<0.001); and has a higher mean BMI (32.4±6.4 kg/m2 vs 31.7±6.2 kg/m2 vs 29.7± 6.2 kg/m2, p< 0.01) than the GDM and the non-DM groups, respectively. The frequency of pre-eclampsia, pre-term delivery, Caesarean-section, macrosomia, LGA and neonatal ICU admissions were significantly higher in the T2DM group compared to GDM and non-DM groups.

Conclusion

Diabetes first detected in pregnancy is equally prevalent among the various ethnic groups residing in Qatar. Newly detected T2DM carries a higher risk of poor pregnancy outcomes; stressing the importance of proper classification of cases of newly detected diabetes in pregnancy.

Health Care Professionals' Attitudes Toward, and Experiences of Using, a Culture-Sensitive Smartphone App for Women with Gestational Diabetes Mellitus: Qualitative Study

Background

The increasing prevalence of gestational diabetes mellitus (GDM) among women of different ethnic backgrounds provides new challenges for health care professionals, who often find it difficult to provide information about the management of this disease to such individuals. Mobile health (mHealth) may act as a useful tool for blood sugar control and care process enhancement. However, little is known about health care professionals’ experiences and attitudes toward the use of mHealth for women with GDM.

Objective

The aim of this study was to explore how health care professionals perceived the provision of care to pregnant women who managed their GDM using the culture-sensitive Pregnant+ app in a randomized controlled trial.

Methods

Individual interviews with 9 health care professionals providing care for women with GDM were conducted. Braun and Clark’s method of thematic content analysis inspired the analysis. This study included health care professionals who were primarily responsible for providing care to participants with GDM in the Pregnant+ randomized controlled trial at 5 diabetes outpatient clinics in Oslo, Norway.

Results

Health care professionals perceived mHealth, particularly the Pregnant+ app, as an appropriate tool for the care of women with GDM, who were described as individuals comprising a heterogeneous, motivated group that could be easily approached with health-related information. Some participants reported challenges with respect to provision of advice to women with different food cultures. The advantages of the Pregnant+ app included provision of information that women could access at home, the information provided being perceived as trustworthy by health care professionals, the culture sensitivity of the app, and the convenience for women to register blood sugar levels. Technical problems, particularly those associated with the automatic transfer of blood glucose measurements, were identified as the main barrier to the use of the Pregnant+ app. Strict inclusion criteria and the inclusion of participants who could not speak Norwegian were the main challenges in the recruitment process for the randomized controlled trial.

Conclusions

The findings of this study suggest that mHealth is a useful tool to enhance the care provided by health care professionals to women with GDM. Future mobile apps for the management of GDM should be developed by a trustworthy source and in cooperation with health care professionals. They should also be culture sensitive and should not exhibit technical problems.

Effect of Glyburide vs Subcutaneous Insulin on Perinatal Complications Among Women With Gestational Diabetes: A Randomized Clinical Trial

IMPORTANCE

Randomized trials have not focused on neonatal complications of glyburide for women with gestational diabetes.

OBJECTIVE

To compare oral glyburide vs subcutaneous insulin in prevention of perinatal complications in newborns of women with gestational diabetes.

DESIGN, SETTINGS, AND PARTICIPANTS

The Insulin Daonil trial (INDAO), a multicenter noninferiority randomized trial conducted between May 2012 and November 2016 (end of participant follow-up) in 13 tertiary care university hospitals in France including 914 women with singleton pregnancies and gestational diabetes diagnosed between 24 and 34 weeks of gestation.

INTERVENTIONS

Women who required pharmacologic treatment after 10 days of dietary intervention were randomly assigned to receive glyburide (n=460) or insulin (n=454). The starting dosage for glyburide was 2.5 mg orally once per day and could be increased if necessary 4 days later by 2.5 mg and thereafter by 5 mg every 4 days in 2 morning and evening doses, up to a maximum of 20 mg/d. The starting dosage for insulin was 4 IU to 20 IU given subcutaneously 1 to 4 times per day as necessary and increased according to self-measured blood glucose concentrations.

MAIN OUTCOMES AND MEASURES

The primary outcome was a composite criterion including macrosomia, neonatal hypoglycemia, and hyperbilirubinemia. The noninferiority margin was set at 7% based on a 1-sided 97.5% confidence interval.

RESULTS

Among the 914 patients who were randomized (mean age, 32.8 [SD, 5.2] years), 98% completed the trial. In a per-protocol analysis, 367 and 442 women and their neonates were analyzed in the glyburide and insulin groups, respectively. The frequency of the primary outcome was 27.6% in the glyburide group and 23.4% in the insulin group, a difference of 4.2% (1-sided 97.5% CI, -∞ to 10.5%; P=.19).

CONCLUSION AND RELEVANCE

This study of women with gestational diabetes failed to show that use of glyburide compared with subcutaneous insulin does not result in a greater frequency of perinatal complications. These findings do not justify the use of glyburide as a first-line treatment.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01731431.

One-hour oral glucose tolerance test plasma glucose at gestational diabetes diagnosis is a common predictor of the need for insulin therapy in pregnancy and postpartum impaired glucose tolerance

Aims/Introduction

Gestational diabetes mellitus (GDM) is a risk for adverse perinatal outcomes, and patients with a history of GDM have an increased risk of impaired glucose tolerance (IGT). Here, we carried out two non‐interventional and retrospective studies of GDM patients in Japan.

Materials and Methods

In the first study, we enrolled 529 GDM patients and assessed predictors of the need for insulin therapy. In the second study, we enrolled 185 patients from the first study, and assessed predictors of postpartum IGT.

Results

In the first study, gestational weeks at GDM diagnosis and history of pregnancy were significantly lower, and pregestational body mass index, family history of diabetes mellitus, 1‐ and 2‐h glucose levels in a 75‐g oral glucose tolerance test (OGTT), the number of abnormal values in a 75‐g OGTT, and glycated hemoglobin were significantly higher in participants receiving insulin therapy. In the second study, 1‐ and 2‐h glucose levels in a 75‐g OGTT, the number of abnormal values in a 75‐g OGTT, glycated hemoglobin, and ketone bodies in a urine test were significantly higher in participants with OGT. Logistic regression analysis showed that gestational weeks at GDM diagnosis, 1‐h glucose levels in a 75‐g OGTT and glycated hemoglobin were significant predictors of the need for insulin therapy, and 1‐h glucose levels in a 75‐g OGTT at diagnosis and ketone bodies in a urine test were significant predictors for postpartum IGT.

Conclusions

Antepartum 1‐h glucose levels in a 75‐g OGTT was a predictor of the need for insulin therapy in pregnancy and postpartum IGT.

Early diabetes screening in pregnancy

The present literature review was conducted to evaluate early diabetes screening in pregnancy. The review focuses on the various guidelines for early screening, the target populations for screening, and the assessment of various early screening targets and strategies. The advantages and disadvantages of each screening method are highlighted. The review emphasizes that there are no validated criteria for selecting high-risk pregnant women for early screening. The different early screening modalities, including fasting plasma glucose, random plasma glucose, postload glucose, and hemoglobin A1c, lack concordance and have not been validated for the early diagnosis of diabetes in pregnancy. Moreover, the benefit of early screening by earlier initiation of treatment has not been shown. Until a randomized controlled trial demonstrates benefit to screening and validates a particular screening method, it is not possible to provide evidence to support any single strategy for early diabetes screening in pregnancy.

Physical fitness and plasma leptin in women with recent gestational diabetes

Aims/Hypothesis

Low physical fitness (PF) is a risk factor for type 2 diabetes mellitus (T2D). Women with a history of gestational diabetes (GDM) are at risk for T2D at a young age, but the role of PF in this population is not clear. PF has also been found to correlate inversely with plasma leptin in previous studies. Here, we examine whether women who had GDM have lower PF than women after a normoglycemic pregnancy and, second, whether PF is associated with plasma leptin, independently of body fat mass.

Methods

Cross-sectional analysis of 236 participants in the PPSDiab Study (cohort study of women 3–16 months after delivery, 152 after gestational diabetes (pGDM), 84 after normoglycemic pregnancy (control subjects); consecutively recruited 2011–16); medical history, physical examination with bioelectrical impedance analysis (BIA), whole body magnetic resonance imaging (MRI) (n = 154), 5-point oral glucose tolerance test, cardiopulmonary exercise testing, clinical chemistry including fasting plasma leptin; statistical analysis with Mann–Whitney U and t -test, Spearman correlation coefficient, multiple linear regression.

Results

Women pGDM had lower maximally achieved oxygen uptake (VO_2peak/kg: 25.7(21.3–29.9) vs. 30.0(26.6–34.1)ml/min/kg; total VO_2peak: 1733(1552–2005) vs. 1970(1767–2238)ml/min; p<0.0001 for both), and maximum workload (122.5(105.5–136.5) vs. 141.0(128.5–159.5)W; p<0.0001). Fasting plasma leptin correlated inversely with PF (VO_2peak/kg ρ = -0.72 p<0.0001; VO_2peak ρ = -0.16 p = 0.015; max. load ρ = -0.35 p<0.0001). These associations remained significant with adjustment for body mass index, or for body fat mass (BIA and MRI).

Conclusions/Interpretation

Women with a recent history of GDM were less fit than control subjects. Low PF may therefore contribute to the risk for T2D after GDM. This should be tested in intervention studies. Low PF also associated with increased leptin levels–independently of body fat. PF may therefore influence leptin levels and signaling. This hypothesis requires further investigation.