Epidemiology of gestational diabetes mellitus and its association with Type 2 diabetes

Visceral Adipose Tissue Depth as a Novel Predictor for Gestational Diabetes Mellitus: A Comprehensive Meta-Analysis and Systematic Review

Background and Objectives: The escalating prevalence of gestational diabetes mellitus (GDM) and the limitations associated with utilizing body mass index (BMI) as a predictive measure underscore the imperative need for identifying an optimal early pregnancy predictor. Such a predictor not only mitigates the risk of GDM but also allows for timely implementation of interventions. Materials and Methods: This meta-analysis aimed to explore the association between visceral adipose tissue (VAT) depth and the risk of GDM. A thorough search of PubMed, Embase, and Web of Science databases was conducted up to 30 September 2023. The analysis employed a random-effects model to assess the relationship between VAT depth and the likelihood of GDM. Results: The inclusion criteria encompassed seven studies involving 1315 women, including 225 diagnosed with GDM. Significantly lower VAT depth was observed in the non-GDM group in comparison to the GDM group (Standardized Mean Difference [SMD]: 0.84; 95% Confidence Interval [CI]: 0.52-1.15; p < 0.001). Substantial statistical heterogeneity was noted among studies (I2 = 72.88%, p = 0.001). Through meticulous sensitivity and subgroup analyses, the source of heterogeneity was identified and thoroughly discussed. Subgroup analyses suggest that different GDM diagnostic criteria and VAT definitions all indicate higher VAT depth in GDM patients during early pregnancy. Conclusions: Our findings propose that, during the first trimester, GDM patients exhibit higher VAT depth compared to non-GDM women, highlighting VAT depth as a potential predictive factor for GDM in early pregnancy. This study contributes valuable evidence to the growing body of knowledge surrounding novel predictors for GDM, emphasizing the importance of early intervention strategies.

Future clinical prospects of C-peptide testing in the early diagnosis of gestational diabetes

Gestational diabetes is typically diagnosed in the late second or third trimester of pregnancy. It is one of the most common metabolic disorders among expectant mothers, with potential serious short- and long-term complications for both maternal and offspring health. C-peptide is secreted from pancreatic beta-cells into circulation in equimolar amounts with insulin. It is a useful biomarker to estimate the beta-cell function because it undergoes negligible hepatic clearance and consequently it has a longer half-life compared to insulin. Pregnancy induces increased insulin resistance due to physiological changes in hormonal and metabolic homeostasis. Inadequate compensation by islet beta-cells results in hyperglycemia. The standard oral glucose tolerance test at 24-28 wk of gestation sets the diagnosis. Accumulated evidence from prospective studies indicates a link between early pregnancy C-peptide levels and the risk of subsequent gestational diabetes. Elevated C-peptide levels and surrogate glycemic indices at the beginning of pregnancy could prompt appropriate strategies for secondary prevention.

Clinical utility of point-of-care glucose testing in the assessment of gestational diabetes: Prospective cohort study

OBJECTIVE

To assess the clinical utility of point-of-care (POC) capillary blood glucose (CBG) testing in the assessment of gestational diabetes mellitus (GDM) during oral glucose tolerance test (OGTT).

DESIGN

Prospective cohort study.

SETTING

Antenatal clinics at King's College Hospital.

POPULATION

Women screened for GDM between March and June 2020.

METHODS

The CBG was measured using the POC StatStrip® test and the venous plasma glucose (VPG) was measured by Roche analyser (Cobas 8000 c702). GDM was diagnosed based on the 2015 National Institute for Health and Clinical Excellence (NICE) Clinical Guideline criteria. The two methods were compared statistically using Analyse-It 5.40.2.

MAIN OUTCOME MEASURES

Diagnostic sensitivity, specificity, positive and negative predictive values (PPV and NPV) for the POC StatStrip® test, compared with VPG measured by reference laboratory method.

RESULTS

A total of 230 women were included. The number and percentage of women with glucose concentrations above the GDM threshold using the POC StatStrip® test versus laboratory VPG measurement was 15 (6.5%) versus eight (3.4%) at fasting and 105 (45.6%) versus 72 (31.1%) at 2 h, respectively. The sensitivity and specificity values (and 95% CIs) for the POC StatStrip® test were 88% (52%-99%) and 97% (93%-98%) at fasting and 97% (91%-99%) and 79% (71%-84%) at 2 h, respectively. However, the specificity and the NPV for the POC StatStrip® test for concentrations of ≤5.0 mmol/L at fasting or <7.5 mmol/L at 2 h were 100%, and the sensitivity and the PPV for concentrations of >9.5 mmol/L at 2 h were 100%.

CONCLUSIONS

In our cohort the POC measurement of CBG cannot entirely replace the laboratory method for the OGTT; however, it can be used to rule out/rule in GDM for glucose concentrations of ≤5.0 mmol/L at fasting or <7.5/>9.5 mmol/L at 2 h.

A Social-Ecological Model Exploring Gestational Diabetes Mellitus Screening Practices Among Antenatal Health Care Providers

Gestational diabetes mellitus (GDM) is associated with adverse health outcomes for the pregnant individual and their baby. Screening approaches for GDM have undergone several iterations, introducing variability in practice among healthcare providers. As such, our study aimed to explore the views of antenatal providers regarding their practices of, and counseling experiences on the topic of, GDM screening in Ontario. We conducted a qualitative, grounded theory study. The study population included antenatal providers (midwives, family physicians, and obstetricians) practicing in Hamilton, Ottawa, or Sudbury, Ontario. Semi-structured telephone interviews were conducted and transcribed verbatim. Transcripts were analyzed using inductive coding upon which codes, categories, and themes were developed to generate a theory grounded in the data. Twenty-two participants were interviewed. Using the social-ecological theory, we created a model outlining four contextual levels that shaped the experiences of GDM counseling and screening: Intrapersonal factors included beliefs, knowledge, and skills; interpersonal factors characterized the patient-provider interactions; organizational strengths and challenges shaped collaboration and health services infrastructure; and finally, guidelines and policies were identified as systemic barriers to health care access and delivery. A focus on patient-centered care was a guiding principle for all care providers and permeated all four levels of the model. Patient-centered care and close attention to barriers and facilitators across intrapersonal, interpersonal, organizational, and policy domains can minimize the impact of variations in GDM screening guidelines. Among care providers, there is a desire for additional skill development related to GDM counseling, and for national consensus on optimal screening guidelines.

Association of urinary polycyclic aromatic hydrocarbon metabolites with gestational diabetes mellitus and gestational hypertension among pregnant women in Southwest China: A cross-sectional study

The association of polycyclic aromatic hydrocarbons (PAHs) with gestational diabetes mellitus (GDM) and gestational hypertension during pregnancy has not yet been established. To investigate the association between PAH exposure and GDM and gestational hypertension, we conducted a cross-sectional study of 4206 pregnant women from the Zunyi birth cohort in southwestern China. Gas chromatography/mass spectrometry was used to detect the urinary levels of 10 monohydroxylated PAHs (OH-PAHs). GDM and gestational hypertension were diagnosed and the relevant information was documented by specialist obstetricians and gynecologists. Logistic regression and restricted cubic spline regression were employed to investigate their single and nonlinear associations. Stratified analyses of pregnancy and body mass index data were conducted to determine their moderating effects on the abovementioned associations. Compared with the first quartile of urinary ∑OH-PAHs, the third or fourth quartile in all study participants was associated with an increased risk of GDM (quartile 3: odds ratio [OR] = 1.35, 95% confidence interval [CI]: 1.03-1.77) and gestational hypertension (quartile 3: OR = 1.88, 95% CI: 1.26-2.81; quartile 4: OR = 1.58, 95% CI: 1.04-2.39), respectively. Nonlinear associations of 1-OH-PYR with GDM (cutoff level: 0.02 μg/g creatinine [Cr]) and 1-OH-PHE with gestational hypertension (cutoff level: 0.06 μg/g Cr) were also observed. In pregnant women with overweight or obesity, 1-OH-PHE and 3-OH-PHE were more strongly associated with gestational hypertension. Our results indicate that exposure to PAH during pregnancy may significantly increase the maternal risks of GDM and gestational hypertension; however, this finding still needs to be confirmed through larger-scale prospective studies and biological evidence.

Association between pregnancy-related complications and development of type 2 diabetes and hypertension in women: an umbrella review

BACKGROUND

Despite many systematic reviews and meta-analyses examining the associations of pregnancy complications with risk of type 2 diabetes mellitus (T2DM) and hypertension, previous umbrella reviews have only examined a single pregnancy complication. Here we have synthesised evidence from systematic reviews and meta-analyses on the associations of a wide range of pregnancy-related complications with risk of developing T2DM and hypertension.

METHODS

Medline, Embase and Cochrane Database of Systematic Reviews were searched from inception until 26 September 2022 for systematic reviews and meta-analysis examining the association between pregnancy complications and risk of T2DM and hypertension. Screening of articles, data extraction and quality appraisal (AMSTAR2) were conducted independently by two reviewers using Covidence software. Data were extracted for studies that examined the risk of T2DM and hypertension in pregnant women with the pregnancy complication compared to pregnant women without the pregnancy complication. Summary estimates of each review were presented using tables, forest plots and narrative synthesis and reported following Preferred Reporting Items for Overviews of Reviews (PRIOR) guidelines.

RESULTS

Ten systematic reviews were included. Two pregnancy complications were identified. Gestational diabetes mellitus (GDM): One review showed GDM was associated with a 10-fold higher risk of T2DM at least 1 year after pregnancy (relative risk (RR) 9.51 (95% confidence interval (CI) 7.14 to 12.67) and although the association differed by ethnicity (white: RR 16.28 (95% CI 15.01 to 17.66), non-white: RR 10.38 (95% CI 4.61 to 23.39), mixed: RR 8.31 (95% CI 5.44 to 12.69)), the between subgroups difference were not statistically significant at 5% significance level. Another review showed GDM was associated with higher mean blood pressure at least 3 months postpartum (mean difference in systolic blood pressure: 2.57 (95% CI 1.74 to 3.40) mmHg and mean difference in diastolic blood pressure: 1.89 (95% CI 1.32 to 2.46) mmHg). Hypertensive disorders of pregnancy (HDP): Three reviews showed women with a history of HDP were 3 to 6 times more likely to develop hypertension at least 6 weeks after pregnancy compared to women without HDP (meta-analysis with largest number of studies: odds ratio (OR) 4.33 (3.51 to 5.33)) and one review reported a higher rate of T2DM after HDP (hazard ratio (HR) 2.24 (1.95 to 2.58)) at least a year after pregnancy. One of the three reviews and five other reviews reported women with a history of preeclampsia were 3 to 7 times more likely to develop hypertension at least 6 weeks postpartum (meta-analysis with the largest number of studies: OR 3.90 (3.16 to 4.82) with one of these reviews reporting the association was greatest in women from Asia (Asia: OR 7.54 (95% CI 2.49 to 22.81), Europe: OR 2.19 (95% CI 0.30 to 16.02), North and South America: OR 3.32 (95% CI 1.26 to 8.74)).

CONCLUSIONS

GDM and HDP are associated with a greater risk of developing T2DM and hypertension. Common confounders adjusted for across the included studies in the reviews were maternal age, body mass index (BMI), socioeconomic status, smoking status, pre-pregnancy and current BMI, parity, family history of T2DM or cardiovascular disease, ethnicity, and time of delivery. Further research is needed to evaluate the value of embedding these pregnancy complications as part of assessment for future risk of T2DM and chronic hypertension.

Effects of the COVID-19 pandemic on gestational diabetes in Castilla-La Mancha (Spain)

SUBJECT-MATTER

To assess the effect of the 2019 coronavirus (COVID-19) pandemic on gestational diabetes (GDM).

MATERIAL AND METHODS

In this retrospective, multicentre, non-interventional study carried out in Castilla-La Mancha, Spain, we compared 663 women with GDM exposed to the pandemic (pandemic group), with 622 women with GDM seen one year earlier (pre-pandemic group). The primary endpoint was a Large for Gestational Age (LGA) newborn as an indicator of poor GDM control. Secondary endpoints included obstetric and neonatal complications.

RESULTS

During the pandemic, the gestational week at diagnosis (24.2 ± 7.4 vs 22.9 ± 7.7, p = 0.0016) and first visit to Endocrinology (26.6 ± 7.2 vs 25.3 ± 7.6, p = 0.0014) were earlier. Face-to-face consultations were maintained in most cases (80.3%). The new diagnostic criteria for GDM were used in only 3% of cases. However, in the pandemic group, the final HbA1c was higher (5.2 ± 0.48 vs 5.29 ± 0.44%, p = 0.047) and there were more LGA newborns (8.5% vs 12.8%, p = 0.015). There were no differences in perinatal complications.

CONCLUSIONS

Care for GDM in our Public Health System did not significantly deteriorate during the COVID-19 pandemic. However, this did not prevent a higher number of LGA newborns.

Prediction of Gestational Diabetes Mellitus in the First Trimester of Pregnancy Based on Maternal Variables and Pregnancy Biomarkers

Gestational diabetes mellitus (GDM) is a significant health concern with adverse outcomes for both pregnant women and their offspring. Recognizing the need for early intervention, this study aimed to develop an early prediction model for GDM risk assessment during the first trimester. Utilizing a prospective cohort of 4917 pregnant women from the Third Department of Obstetrics and Gynecology, Aristotle University of Thessaloniki, Greece, the study sought to combine maternal characteristics, obstetric and medical history, and early pregnancy-specific biomarker concentrations into a predictive tool. The primary objective was to create a series of predictive models that could accurately identify women at high risk for developing GDM, thereby facilitating early and targeted interventions. To this end, maternal age, body mass index (BMI), obstetric and medical history, and biomarker concentrations were analyzed and incorporated into five distinct prediction models. The study's findings revealed that the models varied in effectiveness, with the most comprehensive model combining maternal characteristics, obstetric and medical history, and biomarkers showing the highest potential for early GDM prediction. The current research provides a foundation for future studies to refine and expand upon the predictive models, aiming for even earlier and more accurate detection methods.

Pigment Epithelium-Derived Factor, a Novel Adipokine, Contributes to Gestational Diabetes Mellitus

CONTEXT

Excessive insulin resistance, inadequate insulin compensation, or both could result in gestational diabetes mellitus (GDM). Levels of pigment epithelium-derived factor (PEDF), a novel adipokine that could induce insulin resistance, are high in patients with obesity and diabetes. However, the impact of PEDF in pregnancy remains unknown.

OBJECTIVE

This study aimed to elucidate the role of PEDF on insulin resistance and compensatory elevation of insulin levels during normal pregnancy and in patients with GDM.

METHODS

In this population-based and cohort study, logistic regression analysis was performed to determine the association of PEDF/adiponectin/leptin levels with the risk of developing GDM and to predict postpartum prediabetes. PEDF protein, PEDF transgenic mice, PEDF knockout mice, and PEDF-neutralized antibodies were used to observe changes in insulin resistance and insulin levels with pregnancy.

RESULTS

Plasma PEDF levels were increased in normal pregnancy and higher in GDM women. Higher PEDF levels were associated with the increased risk of developing GDM and emerged as a significant independent determinant of postpartum prediabetes in GDM women. Mechanistically, in vivo and in vitro experiments revealed that PEDF induced insulin resistance by inhibiting the insulin signaling pathway.

CONCLUSION

In addition to insulin resistance and upregulated insulin levels in normal pregnancy and GDM, aberrant PEDF levels can serve as a "fingerprint" of metabolic abnormalities during pregnancy. Thus, PEDF is a valuable biomarker but could interfere with the time course for early diagnosis and prognosis of GDM.

Preventing Gestational Diabetes with a Healthy Gut Diet: Protocol for a Pilot, Feasibility Randomized Controlled Trial

Around 14% of pregnancies globally are affected by gestational diabetes mellitus (GDM), making it one of the most common disorders experienced by women in pregnancy. While dietary, physical activity and supplement interventions have been implemented to prevent GDM, with varying levels of success, altering the gut microbiota through diet is a promising strategy for prevention. Several studies have demonstrated that women with GDM likely have a different gut microbiota to pregnant women without GDM, demonstrating that the gut microbiota may play a part in glycemic control and the development of GDM. To date, there have been no randomized controlled trials using diet to alter the gut microbiota in pregnancy with the aim of preventing GDM. Here, we present the study protocol for a single-blind randomized controlled trial which aims to determine the effectiveness of the Healthy Gut Diet on reducing the diagnosis of GDM in pregnant women with one or more risk factors. Consenting women will be randomized into either the Healthy Gut Diet intervention group or the usual care (control) group after 11 weeks gestation. The women in the intervention group will receive three telehealth counseling appointments with an Accredited Practicing Dietitian with the aim of educating and empowering these women to build a healthy gut microbiota through their diet. The intervention was co-designed with women who have lived experience of GDM and incorporates published behavior change techniques. The control group will receive the usual care and will also be shown a brief (3 min) video on general healthy eating in pregnancy. The primary outcome is the diagnosis of GDM at any stage of the pregnancy. Secondary outcomes include changes to gut microbiota composition and diversity; gestational weight gain; maternal and infant outcomes; management of GDM (where relevant); dietary quality and intake; physical activity; and depression scoring. We aim to recruit 120 women over 16 months. Recruitment commenced in January 2023. The trial has been registered with the Australian New Zealand Clinical Trials Registry (ACTRN12622001285741).

Cholesterol-rich dietary pattern during early pregnancy and genetic variations of cholesterol metabolism genes in predicting gestational diabetes mellitus: a nested case-control study

BACKGROUND

Higher dietary cholesterol intake during pregnancy increases risk of gestational diabetes mellitus (GDM). However, no studies have investigated interindividual variability in cholesterol metabolism and the association of genetics and diet on GDM.

OBJECTIVE

; To prospectively evaluate the joint association of cholesterol-rich dietary patterns and polymorphisms of genes coding for cholesterol metabolism pathway proteins with GDM.

METHODS

A total of 1116 pregnant females from the Tongji Birth Cohort were enrolled. GDM was diagnosed according to a 75-g 2-h oral glucose tolerance test at 24-28 wk of gestation. Dietary data were collected by a validated food frequency questionnaire. The reduced-rank regression method was used to identify dietary patterns using dietary cholesterol as the response variable. Time-of-flight mass spectrometry was used for genotyping. The genetic risk score (GRS) for GDM was constructed with genetic variants in 28 cholesterol metabolism-related single-nucleotide polymorphisms (SNPs). Conditional logistic regression models were used to assess the odds ratio (OR) for GDM.

RESULTS

The cholesterol-rich dietary pattern was rich in livestock and poultry meat and eggs but lower in cereals. The multivariable-adjusted ORs for GDM were 1.24 (95% confidence interval: 1.06-1.44) per SD increment of cholesterol-rich pattern scores and 1.28 (1.09-1.49) per tertile GRS. The variants of the CYP7A1 rs3808607 G→T/rs8192871 G→A/rs7833904 A→T, as well as AGGG and TTGA haplotypes of 4 CYP7A1-spanning SNPs, were significantly associated with GDM. For the joint effect, the OR was 3.53 (1.71-7.31) in the highest categories of both dietary pattern scores and GRS compared with individuals with the lowest strata without significant interaction (P for interaction = 0.101).

CONCLUSIONS

Both a cholesterol-rich dietary pattern and genetic variants of cholesterol metabolism genes are associated with risk of GDM. Adherence to a cholesterol-rich dietary pattern during early pregnancy promotes the chance of GDM, especially in women with higher GRS.

CLINICAL TRIAL REGISTRY

This trial was registered at http://www.chictr.org.cn (Registration number: ChiCTR1800016908). URL: =https://www.chictr.org.cn/showprojEN.html?proj=28081.

Gestational Diabetes Mellitus - The Modern Indian Perspective

Gestational diabetes mellitus (GDM) is a serious and most frequent health complication during pregnancy which is associated with a significant increase in the risk of maternal and neonatal outcomes. GDM is usually the result of β-cell dysfunction along with chronic insulin resistance during pregnancy. Seshiah et al. pioneer work led to the adoption of Diabetes in Pregnancy Study Group in India criteria as the norm to diagnose GDM, especially in the community setting. In 2014, the Maternal Health Division of the Ministry of Health and Family Welfare, Government of India, updated guidelines and stressed upon the proper use of guidelines such as using a glucometer for self-monitoring and the use of oral hypoglycaemic agents. The 2018 Government of India guidelines stress the importance of counselling about lifestyle modifications, weight control, exercise, and family planning.

Perinatal outcomes among Indian-born mothers in Australia

OBJECTIVE

To examine the incidence of adverse perinatal outcomes and the risk of adverse perinatal outcomes for Indian-born mothers compared to other mothers living and giving birth in Australia.

DESIGN, SETTING AND PARTICIPANTS

This retrospective cohort study was designed to investigate all births in Australia in 2012 and those in the Monash Health Birthing Outcomes System (BOS) 2014 to Indian-born mothers in Australia. Data sets were analysed involving descriptive statistics using Statistical Package for Social Sciences (SPSS vs. 23).

RESULTS

Indian-born mothers in Australia are at increased risk of induced labour, emergency caesarean section, very preterm birth (20-27 weeks), babies with low to very low birth weight, and low Apgar score (0-2) at 5 min, gestational diabetes, hypothyroidism, iron deficiency anaemia and vitamin B12 deficiencies compared to other mothers giving birth in Australia. This is despite a range of protective factors (25-34 years, married, nonsmokers, and a BMI < 30) that would normally be expected to reduce the risk of adverse perinatal outcomes for mothers giving birth in a developed country.

CONCLUSION

In the absence of many of the recognized maternal risk factors, Indian-born mothers continue to face increased risk of adverse perinatal outcomes, despite access to high quality maternity care in Australia. Recommendations arising from this study include the need for an intervention study to identify maternal risk factors for Indian-born mothers in mid to late pregnancy that contribute to the risk for very preterm birth and low birth weight.

An Early Mediterranean-Based Nutritional Intervention during Pregnancy Reduces Metabolic Syndrome and Glucose Dysregulation Rates at 3 Years Postpartum

A Mediterranean diet (MedDiet)-based intervention reduces the rate of immediate postpartum maternal metabolic disorders. Whether these effects persist long-term remains to be determined. A total of 2526 normoglycemic women were randomized before the 12th gestational week (GW). IG women followed a MedDiet with extra virgin olive oil (EVOO) (>40 mL/day) and a handful of nuts daily, whereas CG women had to restrict all kinds of dietary fat. At 3 months postpartum, a motivational lifestyle interview was held. The endpoint of the study evaluated the rate of abnormal glucose regulation (AGR) and metabolic syndrome (MetS) at 3 years postpartum in women of the San Carlos cohort. A total of 369/625 (59%) CG women and 1031/1603 (64.3%) IG women were finally analyzed. At 3 months and 3 years postdelivery, the IG women showed higher adherence to the MedDiet, which was associated with lower values of body mass index (BMI) and lipid and glycemic profiles. Body weight change and waist circumference were lower in the IG women. After applying multiple regression analysis, the ORs (95%CI) resulted in AGR (3.18 (2.48-4.08); p < 0.001)/MetS (3.79 (1.81-7.95); p = 0.001) for women with GDM and higher OR for development of MetS in CG women (3.73 (1.77-7.87); p = 0.001). A MedDiet-based intervention early in pregnancy demonstrated persistent beneficial effects on AGR and MetS rates at 3 years postpartum.

Interaction of Iron Homeostasis and Fatty Acid Metabolism in the Development of Glucose Intolerance in Women with Previous Gestational Diabetes Mellitus

A gestational diabetes mellitus (GDM) diagnosis during pregnancy means an increased risk of developing type 2 diabetes later in life. By following up with women after GDM we aimed to examine the relationship between iron parameters, individual fatty acids (FAs) and desaturases in the development of impaired glucose metabolism (IGM). Based on an oral glucose tolerance test (OGTT), six years after GDM, 157 women were grouped as having normal glucose tolerance (NGT) or IGM. Fasting serum FAs, activity of desaturases and iron parameters (ferritin, transferrin, iron, soluble transferrin receptor, total iron binding capacity, hepcidin) were measured, and clinical and anthropometric measurements taken. Soluble transferrin receptor was higher in the IGM group compared to the NGT group (3.87 vs. 3.29 mg/L, p-value = 0.023) and associated positively with saturated FAs and negatively with monounsaturated FAs in the IGM group (adjusted for BMI, age and high sensitivity C-reactive protein; p-value < 0.05). Iron, as well as transferrin saturation, showed a positive association with MUFAs and desaturase activity. These associations were not seen in the NGT group. These results suggest that iron homeostasis and FA metabolism interact in the development of glucose intolerance in women with previous GDM.

Genetic variants in epoxyeicosatrienoic acid processing and degradation pathways are associated with gestational diabetes mellitus

AIM

To explore the genetic effects of CYP2C8, CYP2C9, CYP2J2, and EPHX2, the key genes involved in epoxyeicosatrienoic acid processing and degradation pathways in gestational diabetes mellitus (GDM) and metabolic traits in Chinese pregnant women.

METHODS

A total of 2548 unrelated pregnant women were included, of which 938 had GDM and 1610 were considered as controls. Common variants were genotyped using the Infinium Asian Screening Array. Association studies of single nucleotide polymorphisms (SNPs) with GDM and related traits were performed using logistic regression and multivariable linear regression analyses. A genetic risk score (GRS) model based on 12 independent target SNPs associated with GDM was constructed. Logistic regression was used to estimate odds ratios and 95% confidence intervals, adjusting for potential confounders including age, pre-pregnancy body mass index, history of polycystic ovarian syndrome, history of GDM, and family history of diabetes, with GRS entered both as a continuous variable and categorized groups. The relationship between GRS and quantitative traits was also evaluated.

RESULTS

The 12 SNPs in CYP2C8, CYP2C9, CYP2J2, and EPHX2 were significantly associated with GDM after adjusting for covariates (all P < 0.05). The GRS generated from these SNPs significantly correlated with GDM. Furthermore, a significant interaction between CYP2J2 and CYP2C8 in GDM (P_Interaction = 0.014, OR_Interaction= 0.61, 95%CI 0.41-0.90) was observed.

CONCLUSION

We found significant associations between GDM susceptibility and 12 SNPs of the four genes involved in epoxyeicosatrienoic acid processing and degradation pathways in a Chinese population. Subjects with a higher GRS showed higher GDM susceptibility with higher fasting plasma glucose and area under the curve of glucose and poorer β-cell function.

Trial protocol for the study of recommendation system DiaCompanion with personalized dietary recommendations for women with gestational diabetes mellitus (DiaCompanion I)

Background

Gestational diabetes mellitus (GDM) is a common complication of pregnancy associated with serious adverse outcomes for mothers and their offspring. Achieving glycaemic targets is the mainstream in the treatment of GDM in order to improve pregnancy outcomes. As GDM is usually diagnosed in the third trimester of pregnancy, the time frame for the intervention is very narrow. Women need to get new knowledge and change their diet very quickly. Usually, these patients require additional frequent visits to healthcare professionals. Recommender systems based on artificial intelligence could partially substitute healthcare professionals in the process of educating and controlling women with GDM, thus reducing the burden on the women and healthcare systems. We have developed a mobile-based personalized recommendation system DiaCompanion I with data-driven real time personal recommendations focused primarily on postprandial glycaemic response prediction. The study aims to clarify the effect of using DiaCompanion I on glycaemic levels and pregnancy outcomes in women with GDM.

Methods

Women with GDM are randomized to 2 treatment groups: utilizing and not utilizing DiaCompanion I. The app provides women in the intervention group the resulting data-driven prognosis of 1-hour postprandial glucose level every time they input their meal data. Based on the predicted glucose level, they can adjust their current meal so that the predicted glucose level falls within the recommended range below 7 mmol/L. The app also provides reminders and recommendations on diet and lifestyle to the participants of the intervention group. All the participants are required to perform 6 blood glucose measurements a day. Capillary glucose values are retrieved from the glucose meter and if not available, from the woman's diary. Additionally, data on glycaemic levels during the study and consumption of major macro- and micronutrients will be collected using the mobile app with electronic report forms in the intervention group. Women from the control group receive standard care without the mobile app. All participants are prescribed with insulin therapy if needed and modifications in their lifestyle. A total of 216 women will be recruited. The primary outcome is the percentage of postprandial capillary glucose values above target (>7.0 mmol/L). Secondary outcomes include the percentage of patients requiring insulin therapy during pregnancy, maternal and neonatal outcomes, glycaemic control using glycated hemoglobin (HbA1c), continuous glucose monitoring data and other blood glucose metrics, the number of patient visits to endocrinologists and acceptance/satisfaction of the two strategies assessed using a questionnaire.

Discussion

We believe that the approach including DiaCompanion I will be more effective in patients with GDM for improving glycaemic levels and pregnancy outcomes. We also expect that the use of the app will help reduce the number of clinic visits.

Trial registration number

ClinicalTrials.gov, Identifier NCT05179798.

Obesity and gestational diabetes independently and collectively induce specific effects on placental structure, inflammation and endocrine function in a cohort of South African women

Maternal obesity and gestational diabetes mellitus (GDM) are associated with insulin resistance and health risks for mother and offspring. Obesity is also characterized by low-grade inflammation, which in turn, impacts insulin sensitivity. The placenta secretes inflammatory cytokines and hormones that influence maternal glucose and insulin handling. However, little is known about the effect of maternal obesity, GDM and their interaction, on placental morphology, hormones and inflammatory cytokines. In a South African cohort of non-obese and obese pregnant women with and without GDM, this study examined placental morphology using stereology, placental hormone and cytokine expression using real-time PCR, western blotting and immunohistochemistry, and circulating TNFα and IL-6 concentrations using ELISA. Placental expression of endocrine and growth factor genes was not altered by obesity or GDM. However, LEPTIN gene expression was diminished, syncytiotrophoblast TNFα immunostaining elevated and stromal and fetal vessel IL-6 staining reduced in the placenta of obese women in a manner that was partly influenced by GDM status. Placental TNFα protein abundance and maternal circulating TNFα concentrations were reduced in GDM. Both maternal obesity and, to a lesser extent, GDM were accompanied by specific changes in placental morphometry. Maternal blood pressure and weight gain and infant ponderal index were also modified by obesity and/or GDM. Thus, obesity and GDM have specific impacts on placental morphology and endocrine and inflammatory states that may relate to pregnancy outcomes. These findings may contribute to developing placenta-targeted treatments that improve mother and offspring outcomes, which is particularly relevant given increasing rates of obesity and GDM worldwide. KEY POINTS: Rates of maternal obesity and gestational diabetes (GDM) are increasing worldwide, including in low-middle income countries (LMIC). Despite this, much of the work in the field is conducted in higher-income countries. In a well-characterised cohort of South African women, this study shows that obesity and GDM have specific impacts on placental structure, hormone production and inflammatory profile. Moreover, such placental changes were associated with pregnancy and neonatal outcomes in women who were obese and/or with GDM. The identification of specific changes in the placenta may help in the design of diagnostic and therapeutic approaches to improve pregnancy and neonatal outcomes with particular significant benefit in LMICs.

Exploring patients' perspectives of gestational diabetes mellitus screening and counselling in Ontario: A grounded theory study

INTRODUCTION

Gestational diabetes mellitus (GDM) is associated with adverse perinatal outcomes. Approaches to screening for GDM continue to evolve, introducing potential variability of care. This study explored the impact of these variations on GDM counselling and screening from the perspectives of pregnant individuals.

METHODS

Following a Corbin and Strauss approach to qualitative, grounded theory we recruited 28 individuals from three cities in Ontario, Canada who had a singleton pregnancy under the care of either a midwife, family physician or obstetrician. Convenience and purposive sampling techniques were used. Semi-structured telephone interviews were conducted and transcribed verbatim between March and December 2020. Transcripts were analysed inductively resulting in codes, categories and themes.

RESULTS

Three themes were derived from the data about GDM screening and counselling: 'informing oneself', 'deciding' and 'screening'. All participants, regardless of geographical region, or antenatal care provider, moved through these three steps during the GDM counselling and screening process. Differences in counselling approaches between pregnancy care providers were noted throughout the 'informing' and 'deciding' stages of care. Factors influencing these differences included communication, healthcare autonomy and patient motivation to engage with health services. No differences were noted within care provider groups across the three geographic regions. Participant experiences of GDM screening were influenced by logistical challenges and personal preferences towards testing.

CONCLUSION

Informing oneself about GDM may be a crucial step for facilitating decision-making and screening uptake, with an emphasis on information provision to facilitate patient autonomy and motivation.

PATIENT OR PUBLIC CONTRIBUTION

Participants of our study included patients and service users. Participants were actively involved in the study design due to the qualitative, patient-centred nature of the research methods employed. Analysis of results was structured according to the emergent themes of the data which were grounded in patient perspectives and experiences.

Prediction of recurrent gestational diabetes mellitus: a retrospective cohort study

BACKGROUND

Women after gestational diabetes mellitus (GDM) are at increased risk for development of GDM recurrence. It was the aim of our study to evaluate factors for prediction of risk of recurrence.

METHODS

In this retrospective cohort study we included 159 women with GDM and a subsequent pregnancy. Putative risk factors for GDM recurrence were analyzed by logistic regression models. Results were compared to a cohort of age-matched women without GDM as controls (n = 318).

RESULTS

The overall risk of GDM recurrence was 72.3% (115/159). Risk factors of recurrence were a body mass index (BMI) ≥ 30 kg/m² before the index pregnancy (odds ratio (OR) 2.8 [95% CI 1.3-6.2], p = 0,008), a BMI ≥ 25 kg/m² before the subsequent pregnancy (OR 2.7 [95% CI 1.3-5.8]. p = 0.008), a positive family history (OR 4.3 [95% CI 1.2-15.4], p = 0.016) and insulin treatment during the index pregnancy (OR 2.3 [95% CI 1.1-4.6], p = 0.023). Delivery by caesarean section (index pregnancy) was of borderline significance (OR 2.2 [95% CI 0.9-5.2], p = 0.069). Interpregnancy weight gain, excessive weight gain during the index pregnancy and fetal outcome where not predictive for GDM recurrence. Neonates after GDM revealed a higher frequency of transfer to intensive care unit compared to healthy controls (OR 2.3 [95% CI 1.1-4.6], p = 0.0225). The best combined risk model for prediction of GDM recurrence including positive family history and a BMI ≥ 25 kg/m² before the subsequent pregnancy revealed moderate test characteristics (positive likelihood ratio 7.8 [95% CI 1.1-54.7] and negative likelihood ratio 0.7 [95% CI 0.6-0.9]) with a positive predictive value of 96.6% in our cohort.

CONCLUSIONS

A positive family history of diabetes mellitus in combination with overweight or obesity were strongly associated with recurrence of a GDM in the subsequent pregnancy. Normalization of the pregravid BMI should be an effective approach for reducing the risk of GDM recurrence.

A preliminary report on the association between maternal serum organophosphate ester concentrations and gestational diabetes mellitus

Organophosphate esters (OPEs) are extensively manufactured and used in China. Whether exposure to OPEs during pregnancy increases the risk of gestational diabetes mellitus (GDM) is unknown. Between 2011 and 2012, a case-control study including 130 and 67 women with and without GDM, respectively, was conducted in Hangzhou, China. The levels of 10 OPEs in maternal serum samples at delivery were quantified, and the relationships between the OPE concentrations and GDM risk were investigated. The results show that in all participants, tri-n-butyl phosphate (TNBP, median: 2.02 ng/mL) was the most common OPE present in the serum, followed by tri-phenyl phosphate (TPHP, median: 1.74 ng/mL) and tri-iso-butyl phosphate (median: 1.68 ng/mL). With one-unit elevation in the tris (2-chloroethyl) phosphate, TNBP, TPHP, and tris (2-butoxy ethyl) phosphate (TBOEP) concentrations in maternal serum, 1-h glucose levels increased by 0.19 (95% confidence interval (CI): -0.01, 0.29), 0.11 (95% CI: -0.18, 0.62), 0.29 (95% CI: 0.12, 0.58), and 0.20 units (95% CI: 0.01, 0.44), respectively. In addition, a unit increase in TBOEP levels in maternal serum was associated with an increase of 0.26 units (95% CI: 0.09, 0.61) in 2-h glucose levels. After adjusting for covariate factors, serum TNBP (odds ratio (OR) = 2.07; 95% CI: 1.27, 3.41), TBOEP (OR = 2.63; 95% CI: 1.68, 4.11), and TPHP (OR = 1.03; 95% CI: 1.05, 1.51) concentrations were associated with GDM incidence in pregnant women. Overall, TNBP, TBOEP, and TPHP exposure during pregnancy is associated with GDM risk and increased glucose levels.

Effects of exposure to phthalate during early pregnancy on gestational diabetes mellitus: a nested case-control study with propensity score matching

Owing to the complexity of phthalates (PAEs) components and the diversity of their sources, the health hazards of their metabolites to pregnant women remain unclear. This study aimed to explore the relationship between exposure to PAEs during early pregnancy and gestational diabetes mellitus (GDM) in rural pregnant women. We assessed pregnant women with (n = 338) or without (n = 3082) GDM from the ongoing Zunyi Birth Cohort. Participants' urine samples were collected to measure the levels of 10 metabolites of PAEs. GDM was diagnosed using the 75-g oral glucose tolerance test at 24-28 weeks of gestation. We adopted propensity score matching based on GDM-related factors and pregnant women's backgrounds to establish two groups of 338 patients: those with or without GDM. In the cohort, we included 5734 pregnant women; 519 of them developed GDM, yielding a GDM incidence rate of 9.05%. Urinary concentrations of monooctyl phthalate (MOP), mono-benzyl phthalate (MBzP), mono(2-ethyl-5-oxyhexyl) phthalate (MEOHP), and mono(2-ethyl-5-carboxypentyl) phthalate (MECPP) during early pregnancy were significantly associated with GDM (P < 0.05). Logistic regression models revealed that MEOHP in the urine was positively associated with GDM (odds ratio [OR] = 1.55; 95% confidence interval [CI]: 1.00-2.39). Furthermore, restricted cubic spline models revealed that urine MEOHP concentrations greater than 15.6 μg/L were positively associated with GDM, and approximately 23.5% pregnant women had urine MEOHP concentrations greater than 15.6 μg/L. Thus, approximately 23.5% of pregnant women were at the risk of developing GDM due to MEOHP, which suggested that pregnant women should reduce the use of packaged food and cosmetics to reduce the risk of GDM. However, further molecular biology experiments are required to confirm these findings and to elucidate the underlying mechanisms.

The relationship between air pollutants and gestational diabetes: an updated systematic review and meta-analysis

PURPOSE

Air pollution is an environmental stimulus that may predispose pregnant women to gestational diabetes mellitus (GDM). This systematic review and meta-analysis were conducted to investigate the relationship between air pollutants and GDM.

METHODS

PubMed, Web of Science, and Scopus were systematically searched for retrieving English articles published from January 2020 to September 2021, investigating the relationship of exposure to ambient air pollution or levels of air pollutants with GDM and related parameters, including fasting plasma glucose (FPG), insulin resistance, and impaired glucose tolerance. Heterogeneity and publication bias were evaluated using I-squared (I2), and Begg's statistics, respectively. We also performed the subgroup analysis for particulate matters (PM2.5, PM10), Ozone (O3), and sulfur dioxide (SO2) in the different exposure periods.

RESULTS

A total of 13 studies examining 2,826,544 patients were included in this meta-analysis. Compared to non-exposed women, exposure to PM2.5 increases the odds (likelihood of occurrence outcome) of GDM by 1.09 times (95% CI 1.06, 1.12), whereas exposure to PM10 has more effect by OR of 1.17 (95% CI 1.04, 1.32). Exposure to O3 and SO2 increases the odds of GDM by 1.10 times (95% CI 1.03, 1.18) and 1.10 times (95% CI 1.01, 1.19), respectively.

CONCLUSIONS

The results of the study show a relationship between air pollutants PM2.5, PM10, O3, and SO2 and the risk of GDM. Although evidence from various studies can provide insights into the linkage between maternal exposure to air pollution and GDM, more well-designed longitudinal studies are recommended for precise interpretation of the association between GDM and air pollution by adjusting all potential confounders.

Type 1 and other types of diabetes mellitus in the perioperative period. What the anaesthetist should know

Diabetes mellitus is often treated as a uniform disease in the perioperative period. Type 2 diabetes is most commonly encountered, and only a minority of surgical patients have been diagnosed with another type of diabetes. Patients with a specific type of diabetes can be particularly prone to perioperative glycaemic dysregulation. In addition, certain type-related features and pitfalls should be taken into account in the operating theatre. In this narrative review, we discuss characteristics of types of diabetes other than type 2 diabetes relevant to the anaesthetist, based on available literature and data from our clinic.

The impact of maternal diabetes on birth to placental weight ratio and umbilical cord oxygen values with implications for fetal-placental development

INTRODUCTION

We determined the impact of gestational diabetes (GDM) and pre-existing diabetes (DM) on birth/placental weight and cord oxygen values with implications for placental efficiency and fetal-placental growth and development.

METHODS

A hospital database was used to obtain birth/placental weight, cord PO₂ and other information on patients delivering between Jan 1, 1990 and Jun 15, 2011 with GA >34 weeks (N = 69,854). Oxygen saturation was calculated from the cord PO₂ and pH data, while fetal O₂ extraction was calculated from the oxygen saturation data. The effect of diabetic status on birth/placental weight and cord oxygen values was examined adjusting for covariates.

RESULTS

Birth/placental weights were stepwise decreased in GDM and DM compared to non-diabetics with placentas disproportionally larger indicating decreasing placental efficiency. Umbilical vein oxygen was marginally increased in GDM but decreased in DM attributed to the previously reported hyper-vascularization in diabetic placentas with absorbing surface area of capillaries initially increased, but then constrained by increasing distance from maternal blood within the intervillous space. Umbilical artery oxygen was unchanged in GDM and DM, with fetal O₂ extraction decreased in DM indicating that fetal O₂ delivery must be increased relative to O₂ consumption and likely due to increased umbilical blood flow.

DISCUSSION

Increased villous density/hyper-vascularization in GDM and DM with placentas disproportionately larger and umbilical blood flow increased, are postulated to normalize umbilical artery oxygen despite increased birth weights and growth-related O₂ consumption. These findings have implications for mechanisms signaling fetal-placental growth and development in diabetic pregnancies and differ from that reported with maternal obesity.

Number of Children and Risk of Cardiovascular Disease in Japanese Women: Findings from the Tohoku Medical Megabank

AIM

Cardiovascular disease (CVD) is the second largest cause of death in Japanese women. Pregnancy and childbirth are events that put a strain on the cardiovascular system. When postpartum weight retention is insufficient, weight gain due to fat deposition during pregnancy might lead to obesity. Thus, we examined the effects of body mass index (BMI) in middle and older ages and the number of children on CVD and metabolic disorders.

METHODS

From the Tohoku Medical Megabank database, we used data from 32,000 women aged ≥ 50 years. This database contains obstetrical history, medical history, and laboratory data obtained once from 2013 to 2015.

RESULTS

The mean age of participants was 64.2 years, and 47.7% of women had two children. Compared with nulliparous women, those who had a higher number of children had higher BMI and systolic blood pressure. The prevalence of CVD was highest in obese class I (30 kg/m² ≤ BMI) women with three or more children and the prevalence of hypertension was high in pre-obese (25 kg/m² ≤ BMI ＜30 kg/m²) and obese class I women with children. Conversely, the prevalence of diabetes and proportion of women whose HbA1c values were ＞6.5% was highest in obese class I women with no children.

CONCLUSION

In this study, we found that not only BMI but also the number of children influenced the health status of middle- and older-aged women, suggesting the importance of childbirth history in the health management of women.

Serum concentrations of phthalate metabolites in pregnant women and their association with gestational diabetes mellitus and blood glucose levels

Phthalate metabolites are widely present in humans and can have many adverse effects on pregnant women. To date, many studies on the effects of phthalate metabolites on the risk of gestational diabetes mellitus (GDM) have been published, but the findings of these studies are controversial. We conducted a case-control study to quantify the concentrations of seven phthalate metabolites in the serum of pregnant women and to investigate their association with the risk of GDM and blood glucose levels in pregnant women. Therefore, 201 serum samples (139 pregnant women with GDM and 62 control serum samples) were collected from Hangzhou, China, between 2011 and 2012. The results showed that mono butyl phthalate (MBP; mean = 4.08 ng/mL) was the most abundant phthalate metabolites in human serum, followed by mono (2-ethylhexyl) phthalate (MEHP; mean = 1.28 ng/mL) and mono isobutyl phthalate (MiBP; mean = 1.20 ng/mL). The other results indicated significant associations between MBP (β = 2.24, 95 % confidence interval (CI): 1.02, 5.07, P = 0.050) and MiBP (β = 1.84, 95 % CI: 1.03, 3.31, P = 0.041) concentrations in human serum and the incidence of GDM. Moreover, serum MBP (β = 0.40, 95 % CI: 0.10, 0.70, P = 0.010) and MiBP levels (β = 0.18, 95 % CI: 0.010, 0.35, P = 0.047) in humans were positively associated with 2-hour blood glucose levels. Our study provides affirmative evidence on previously inconsistent findings that MBP and MiBP exposure may increase the risk of GDM in pregnant women.

miR-24-3p and Body Mass Index as Type 2 Diabetes Risk Factors in Spanish Women 15 Years after Gestational Diabetes Mellitus Diagnosis

Gestational diabetes mellitus (GDM) is defined as any degree of glucose intolerance that is diagnosed for the first time during pregnancy. The objective of this study is to know the glucose tolerance status after 15 years of pregnancy in patients diagnosed with gestational diabetes and to assess the long-term effect of GDM on the circulating miRNA profile of these women. To answer these, 30 randomly selected women diagnosed with GDM during 2005-2006 were included in the study, and glucose tolerance was measured using the National Diabetes Data Group criteria. Additionally, four miRNAs (hsa-miR-1-3p, hsa-miR-24-3p, hsa-miR-329-3p, hsa-miR-543) were selected for their analysis in the plasma of women 15 years after the diagnosis of GDM. In our study we discovered that, fifteen years after the diagnosis of GDM, 50% of women have some degree of glucose intolerance directly related to body weight and body mass index during pregnancy. Dysglycemic women also showed a significantly increased level of circulating hsa-miR-24-3p. Thus, we can conclude that initial weight and BMI, together with circulating expression levels of hsa-miR-24-3p, could be good predictors of the future development of dysglycemia in women with a previous diagnosis of GDM.

Integrative metagenomic and metabolomic analyses reveal gut microbiota-derived multiple hits connected to development of gestational diabetes mellitus in humans

Gestational diabetes mellitus (GDM) is characterized by the development of hyperglycemia and insulin resistance during the second or third trimester of pregnancy, associated with considerable risks to both the mother and developing fetus. Although emerging evidence suggests an association between the altered gut microbiota and GDM, remarkably little is known about the microbial and metabolic mechanisms that link the dysbiosis of the gut microbiota to the development of GDM. In this study, a metagenome-wide association study and serum metabolomics profiling were performed in a cohort of pregnant women with GDM and pregnant women with normal glucose tolerance (NGT). We identified gut microbial alterations associated with GDM and linked to the changes in circulating metabolites. Blood metabolite profiles revealed that GDM patients exhibited a marked increase in 2-hydroxybutyric acid and L-alpha-aminobutyric acid, but a decrease in methionine sulfoxide, allantoin, and dopamine and dopaminergic synapse, when compared with those in NGT controls. Short-chain fatty acid-producing genera, including Faecalibacterium, Prevotella, and Streptococcus, and species Bacteroides coprophilus, Eubacterium siraeum, Faecalibacterium prausnitzii, Prevotella copri, and Prevotella stercorea, were significantly reduced in GDM patients relative to those in NGT controls. Bacterial co-occurrence network analysis revealed that pro-inflammatory bacteria were over-represented as the core species in GDM patients. These microbial and metabolic signatures are closely associated with clinical parameters of glucose metabolism in GDM patients and NGT controls. In conclusion, we identified circulating dopamine insufficiency, imbalanced production of SCFAs, and excessive metabolic inflammation as gut microbiota-driven multiple parallel hits linked to GDM development. This work might explain in part the mechanistic link between altered gut microbiota and GDM pathogenesis, and suggest that gut microbiota may serve as a promising target to intervene in GDM.

The gestational diabetes future diabetes prevention study (GODDESS): A partially randomised feasibility controlled trial

OBJECTIVES

To assess the feasibility of an ante- and post-natal lifestyle intervention for women with gestational diabetes mellitus (GDM) to reduce type 2 diabetes risk.

DESIGN

A partially randomised patient preference feasibility trial.

SETTING

Diabetes antenatal clinics in two inner-London hospitals, UK.

PARTICIPANTS

Pregnant women ≥18 years with a GDM diagnosis and pre-pregnancy body mass index of ≥25kg/m2.

INTERVENTION

Participants in the intervention group were offered four motivational interview-based sessions (two antenatally and two postnatally, at 3 and 6 months postpartum), a WhatsApp support group, a FitBit and electronic self-help resources.

OUTCOME MEASURES

Recruitment; retention; intervention dose received; data completion; adaptions; proportion achieving ≥5% weight loss; weight change, blood glucose; blood pressure; diet, physical activity, breastfeeding and depression. Clinical outcomes were measured at baseline and 6 months postpartum.

RESULTS

50 participants were recruited from 155 eligible women (32% recruitment rate). Thirty-four were recruited to the intervention group (23 following randomisation (RI-group) and 11 based on preference (PI-group)); and 16 to the control group (13 randomised (RC-group) and 3 preference (PC-group)). Attrition was 44% (n = 22/50). Forty-six percent (n = 6) of the intervention group (25% (n = 2) of the RI-group and 80% (n = 4) of the PI-group) achieved ≥5% weight loss compared to 8% (n = 1) in the control group (95% confidence interval (CI) -0.69 to 0.07). Mean weight change was -2.1kg±9.0 in the intervention group (0kg±5.4 in the RI-group and -5.4kg±13.0 in the PI-group) compared to +4.4kg±4.9 in the control group (RC +4.4kg ±5.3 and PC +4.7kg ±3.1, 95% CI -12.4 to 0.2).

CONCLUSIONS

Recruitment was feasible, but strategies to improve retention are needed. The findings suggest the intervention can support women with GDM to lose weight. The observed weight loss was primarily in women who preferred the intervention. Therefore, future trials may need to adopt a preference design and consider factors associated with preference.

TRIAL REGISTRATION

Trial registration: ISRCTN52675820 https://www.isrctn.com/ISRCTN52675820?q=ISRCTN52675820&filters=&sort=&offset=1&totalResults=1&page=1&pageSize=10&searchType=basic-search.

Association of ambient fine particulate matter exposure with gestational diabetes mellitus and blood glucose levels during pregnancy

BACKGROUND

Previous studies have examined the associations between ambient fine particulate matter (PM_2.5) exposure and gestational diabetes mellitus (GDM). However, limited studies explored the relationships between PM_2.5 exposure and blood glucose levels during pregnancy, especially in highly polluted areas.

OBJECTIVES

To examine the associations of prenatal ambient PM_2.5 exposure with GDM and blood glucose levels, and to identify the sensitive exposure windows in a highly air-polluted area.

METHODS

From July 2016 to October 2017, a birth cohort study was conducted in Beijing, China. Participants were interviewed in each trimester regarding demographics, lifestyle, living and working environment, and medical conditions. Participant's daily ambient PM_2.5 levels from 3 m before last menstrual period (LMP) to the third trimester was estimated by a hybrid spatiotemporal model. Indoor air quality index was calculated based on environmental tobacco smoke, ventilation, cooking, painting, pesticide, and herbicide use. Distributed lag non-linear model was applied to explore the sensitive weeks of PM_2.5 exposure.

RESULTS

Of 165 pregnant women, 23 (13.94%) developed GDM. After adjusting for potential confounders, PM_2.5 exposure during the 1^st trimester was associated with higher odds of GDM (10 μg/m³ increase: OR = 1.89, 95% CI: 1.04-3.49). Each 10 μg/m³ increase in PM_2.5 during the 2^nd trimester was associated with 17.70% (2.21-33.20), 15.99% (2.96-29.01), 18.82% (4.11-33.52), and 17.10% (3.28-30.92) increase in 1-h, 2-h, Δ1h-fasting (1-h minus fasting), and Δ2h-fasting (2-h minus fasting) blood glucose levels, respectively. PM_2.5 exposure at 24^th-27^th weeks after LMP was associated with increased GDM risk. We identified sensitive exposure windows of 21^st-24^th weeks for higher 1-h and 2-h blood glucose levels and of 20^th-22^nd weeks for increased Δ1h-fasting and Δ2h-fasting.

CONCLUSIONS

Ambient PM_2.5 exposure during the second trimester was associated with higher odds of GDM and higher blood glucose levels. Avoiding exposure to high air pollution levels during the sensitive windows might prevent women from developing GDM.

Association of Selenium Levels with Gestational Diabetes Mellitus: An Updated Systematic Review and Meta-Analysis

Several studies have investigated the association between selenium levels and gestational diabetes mellitus (GDM); however, their results are not conclusive. This systematic review and meta-analysis aimed to update and draw conclusions regarding the evidence from published studies that investigated selenium levels in relation to GDM. PubMed, Google Scholar, Cochrane Library and ScienceDirect were searched for studies related to selenium and GDM, published from the inception of each database through to July 2022. The meta-analysis was conducted by measuring the standardized mean difference (SMD) between the selenium levels of women with GDM and those pregnant without GDM (control group). Stratified meta-analysis, meta-regression analysis and reporting bias were applied. The "meta" package in the open-access software R was used to analyze all of the data. A total of 12 studies, including 940 pregnant women with GDM and 1749 controls met this study's inclusion criteria. The selenium levels were significantly lower in women with GDM compared with the control group (SMD = -0.66; 95% confidence interval (CI): (-1.04, -0.28); p ≤ 0.001). Due to significant heterogeneity (I2 = 94%, Cochrane Q = 186.7; p ≤ 0.0001), the random-effects model was followed. The stratified meta-analysis showed that the selenium levels were lower in the cases compared with the normal controls in the third trimester (SMD = -1.85 (-3.03, -0.66); p ≤ 0.01). The same trend was observed in the studies published before the year 2014 (SMD = -0.99 (-1.70, -0.28); p ≤0.01) and those published in or after 2014 (SMD = -0.45 (-0.90, 0.00); p = 0.05). None of the investigated covariates in the meta-regression analysis (each study's geographic location, trimester of selenium quantification, World Bank economic classification, method of selenium determination, study design, study quality score, publication year and study's sample size) were significantly associated with the selenium SMD. The current evidence indicates that selenium levels are lower among women with GDM in comparison to those without GDM; however, after the correction of the reporting bias, the result was no longer significant. Further studies with more prospective designs are needed to confirm this evidence and explain the function of selenium in GDM throughout pregnancy.

Deep Insight of the Pathophysiology of Gestational Diabetes Mellitus

Diabetes mellitus is a severe metabolic disorder, which consistently requires medical care and self-management to restrict complications, such as obesity, kidney damage and cardiovascular diseases. The subtype gestational diabetes mellitus (GDM) occurs during pregnancy, which severely affects both the mother and the growing foetus. Obesity, uncontrolled weight gain and advanced gestational age are the prominent risk factors for GDM, which lead to high rate of perinatal mortality and morbidity. Zn in-depth understanding of the molecular mechanism involved in GDM will help researchers to design drugs for the optimal management of the condition without affecting the mother and foetus. This review article is focused on the molecular mechanism involved in the pathophysiology of GDM and the probable biomarkers, which can be helpful for the early diagnosis of the condition. The early diagnosis of the metabolic disorder, most preferably in first trimester of pregnancy, will lead to its effective long-term management, reducing foetal developmental complications and mortality along with safety measures for the mother.

Placental DNA Methylation in pregnancies complicated by maternal diabetes and/or obesity: State of the Art and research gaps

SUMMARYMaternal diabetes and/or obesity in pregnancy are undoubtedly associated with later disease-risk in the offspring. The placenta, interposed between the mother and the fetus, is a potential mediator of this risk through epigenetic mechanisms, including DNA methylation. In recent years, multiple studies have identified differentially methylated CpG sites in the placental tissue DNA in pregnancies complicated by diabetes and obesity. We reviewed all published original research relevant to this topic and analyzed our findings with the focus of identifying overlaps, contradictions and gaps. Most studies focused on the association of gestational diabetes and/or hyperglycemia in pregnancy and DNA methylation in placental tissue at term. We identified overlaps in results related to specific candidate genes, but also observed a large research gap of pregnancies affected by type 1 diabetes. Other unanswered questions relate to analysis of specific placental cell types and the timing of DNA methylation change in response to diabetes and obesity during pregnancy. Maternal metabolism is altered already in the first trimester involving structural and functional changes in the placenta, but studies into its effects on placental DNA methylation during this period are lacking and urgently needed. Fetal sex is also an important determinant of pregnancy outcome, but only few studies have taken this into account. Collectively, we provide a reference work for researchers working in this large and evolving field. Based on the results of the literature review, we formulate suggestions for future focus of placental DNA methylation studies in pregnancies complicated by diabetes and obesity.

Dynamic regulation of lipid metabolism in the placenta of in vitro and in vivo models of Gestational Diabetes Mellitus

The purpose of this study was to investigate lipid metabolism in the placenta of Gestational diabetes mellitus (GDM) individuals and to evaluate its effect on the fetus. We examined the expression of lipogenesis- and lipolysis-related proteins in the in vitro and in vivo GDM placenta models. The levels of sterol regulatory element binding protein-1c (SREBP-1c) were increased, and fat accumulated more during early hyperglycemia, indicating that lipogenesis was stimulated. When hyperglycemia was further extended, lipolysis was activated due to the phosphorylation of hormone-sensitive lipase (HSL) and expression of adipose triglyceride lipase (ATGL). In the animal model of GDM and in the placenta of GDM patients during the extended stage of GDM, the expression of SREBP-1c decreased and the deposition of fat increased. Similar to the results obtained in the in vitro study, lipolysis was enhanced in the animal and human placenta of extended GDM. These results suggest that fat synthesis may be stimulated by lipogenesis in the placenta when the blood glucose level is high. Subsequently, the accumulated fat can be degraded by lipolysis and more fat and its metabolites can be delivered to the fetus when the GDM condition is extended at the late stage of gestation. Imbalanced fat metabolism in the placenta and fetus of GDM patients can cause metabolic complications in the fetus, including fetal macrosomia, obesity, and type 2 diabetes mellitus.

Urinary tract infection in patients with diabetes mellitus and the role of parental genetics in the emergence of the disease

This study aimed to assess the role of paternal genetics in the development of diabetic mellitus (DM) and determine the impact of DM on the urinary system by investigating the percentage of patients with urinary tract infection (UTI). The study included 100 people with DM; their ages ranged from 5 to 83 years. The DM and blood sugar levels were diagnosed clinically and at a laboratory in Al-Zahra Teaching Hospital and the outpatient clinics. The age, gender, and causes of DM and the family history of diabetes were reported. Isolation and identification of bacterial species were made depending on culture media and biochemical tests. The average age of patients was 47.7±5.5, and most of them were female (67%). The incidence of DM increased with age, and the main cause of DM was likely to be a genetic predisposition (family history), where 32% of patients appeared to have a positive family history and the presence of DM in both parents or only the mother had a significant role in increasing the genetic predisposition of developing DM. Among the non-genetic causes of DM, the most common was exposure to sudden psychological or nervous shock (41%). Obesity also had an important role in the development of diabetes, and also pregnancy and smoking. Moreover, 66% of patients with type 2 DM and all with type 1 DM suffered from UTIs. The main causative agents were E. coli (60%) and Proteus spp. (13%). The majority of patients suffering from UTIs (73%) were females. In conclusion, type 2 DM is the most common, especially in females, and increases with age. The main cause of DM was family genetic predisposition and sudden shocks. The current study also showed that most diabetic patients suffered from UTIs, especially females, and the main causes of UTI inflammation are E. coli isolates.

Orphan nuclear receptor NUR77 relieves insulin resistance in HTR-8/SVneo trophoblast cells through activation of autophagy and insulin signaling

Gestational diabetes mellitus (GDM) is a common pregnancy complication with a high incidence in women. Orphan nuclear receptor NUR77 is involved in regulating glucose metabolism. However, its role in GDM has not been fully elucidated yet. In this study, an animal model of GDM was established by feeding mice with a high-fat diet (HFD) before and during pregnancy. NUR77 expression was abnormally upregulated in placenta tissues of GDM mice. We performed gain- and loss-of-function studies of NUR77 in HTR-8/SVneo cells. Cells were incubated with 1 × 10^-6 M insulin for 48 h to induce insulin resistance (IR). The expression of NUR77 was downregulated in HTR-8/SVneo cells following IR induction. Overexpression of NUR77 promoted cell proliferation, migration, and invasion. Notably, NUR77 promoted glucose uptake and enhanced insulin sensitivity in vitro. NUR77 increased the ratio of p-insulin receptor β (IRβ)^Tyr1361/IRβ, p-insulin receptor substrate (IRS)-1^Tyr612/IRS-1, p-Akt/Akt and decreased p-IRS-1^Ser307/IRS-1, as well as lowered the expression of glucose transport protein type 1 (GLUT1) and elevated GLUT4. These results suggest the involvement of IRβ/IRS/Akt/GLUT4 signaling activation in the regulatory effects of NUR77 on IR in HTR-8/SVneo cells. Silencing of NUR77 displayed opposite effects. Besides, NUR77 enhanced the expression of autophagy-related protein Beclin 1 and the ratio of LC3II/LC3I. Further study demonstrated that the inhibitory effect of NUR77 on IR was partially attributed to the activation of autophagy. Therefore, we demonstrate that NUR77 enhances insulin sensitivity in HTR-8/SVneo cells likely through activating IRβ/IRS/Akt/GLUT4 pathway and regulating autophagy.

Insulin Resistance in Gestational Diabetes Mellitus and Its Association With Anthropometric Fetal Indices

Background:

In pregnant women with gestational diabetes mellitus (GDM), insulin resistance (IR) increases the risk of developing manifest type 2 diabetes mellitus and is associated with complications in both mother and fetus.

Objectives:

This research aimed to evaluate the associations between IR evaluated by 3 indices (namely updated homeostasis model assessment model (HOMA2), QUICKI, and McAuley’s index) and the diabetes risk factors and the fetal growth indices in Vietnamese women with GDM.

Methods:

A cross-sectional descriptive study was conducted on 370 women with GDM and 40 healthy pregnant women from January 2015 to May 2019. IR was calculated by HOMA2 (HOMA2-IR), QUICKI, and McAuley’s index. Fetal anthropometric measurements were assessed via ultrasound which was performed and interpreted by ultrasound experts.

Results:

In the simple regression analysis, McAuley’s index illustrated had statistically significant correlations to the highest number of risk factors of diabetes mellitus compared with HOMA2-IR and QUICKI indices. Moreover, McAuley’s index correlated statistically significantly to the highest number of fetal ultrasound measurements factors such as including biparietal diameter (BPD) (r = −0.271, P < .001), head circumference (HC) (r = −0.225, P < .001), abdominal circumference (AC) (r = −0.214, P < .001), femur length (FL) (r = −0.231, P < .001), estimated fetal weight (EFW) (r = −0.239, P < .001) and fetal estimated age (r = −0.299, P < .001). In the multivariable analysis, the McAuley’s index contributed the greatest to AC (Standardized B of −0.656, P < .001).

Conclusion:

The McAuley’s index was significantly associated with a higher number of more risk factors for diabetes mellitus as well as fetal ultrasound sonography findings measurements than compared with HOMA2-IR and QUICKI indices.

Vitamin D Status and Gestational Diabetes in Russian Pregnant Women in the Period between 2012 and 2021: A Nested Case-Control Study

Several meta-analyses found an association between low maternal serum 25-hydroxyvitamin D (25(OH)D) level and gestational diabetes mellitus (GDM). However, some of them reported significant heterogeneity. We examined the association of serum 25(OH)D concentration measured in the first and in the second halves of pregnancy with the development of GDM in Russian women surveyed in the periods of 2012−2014 and 2018−2021. We conducted a case−control study (including 318 pregnant women) nested on two previous studies. In 2012−2014, a total of 214 women (83 GDM and 131 controls) were enrolled before 15 weeks of gestation and maternal serum 25(OH)D concentrations were measured twice: at 8th−14th week of gestation and simultaneously with two-hour 75 g oral glucose tolerance test (OGTT) at 24th−32nd week of gestation. In the period of 2018−2021, 104 women (56 GDM and 48 controls) were included after OGTT and 25(OH)D concentrations were measured at 24th−32nd week of gestation. Median 25(OH)D levels were 20.0 [15.1−25.7] vs. 20.5 [14.5−27.5] ng/mL (p = 0.565) in GDM and control group in the first half of pregnancy and 25.3 [19.8−33.0] vs. 26.7 [20.8−36.8] ng/mL (p = 0.471) in the second half of pregnancy, respectively. The prevalence rates for vitamin D deficiency (25(OH)D levels < 20 ng/mL) were 49.4% and 45.8% (p = 0.608) in the first half of pregnancy and 26.2% vs. 22.1% (p = 0.516) in the second half of pregnancy in women who developed GDM and in women without GDM, respectively. The frequency of vitamin D supplements intake during pregnancy increased in 2018−2021 compared to 2012−2014 (p = 0.001). However, the third trimester 25(OH)D levels and prevalence of vitamin D deficiency (25.5 vs. 23.1, p = 0.744) did not differ in women examined in the periods of 2012−2014 and 2018−2021. To conclude, there was no association between gestational diabetes risk and maternal 25(OH)D measured both in the first and in the second halves of pregnancy. The increased prevalence of vitamin D supplements intake during pregnancy by 2018−2021 did not lead to higher levels of 25(OH)D.

Ovarian hyperstimulation syndrome and adverse pregnancy outcome

INTRODUCTION

The aim of this study was to investigate the association between ovarian hyperstimulation syndrome (OHSS) and adverse pregnancy outcome.

EVIDENCE ACQUISITION

Medline, Embase and Cochrane databases were searched. The primary outcome was a composite score of adverse maternal outcome including either preterm birth (PTB), gestational diabetes mellitus (GDM), pre-eclampsia (PE) or pregnancy induced hypertension, intrahepatic cholestasis of pregnancy, thromboembolic events or need for caesarean section (CS). Secondary outcomes were a composite score of adverse fetal outcome including either miscarriage, low birthweight, fetal anomalies or intrauterine fetal death (IUD) and the individual components of both primary and secondary outcomes.

EVIDENCE SYNTHESIS

Thirteen studies (3303 ART pregnancies with and 89,720 without OHSS) were included. The risk of composite adverse maternal outcome (RR: 8.8, 95% CI: 8.1-9.5) was higher in women with compared to those without OHSS. The association between OHSS and adverse pregnancy outcome was mainly due to the higher risk of PTB (RR: 11.4, 95% CI: 10.5-12.4), while there was no difference in the risk of others primary outcome. Likewise, the risk of composite fetal outcome was higher in pregnancies with a prior OHSS (RR: 1.5, 95% CI: 1.1-2.0). The strength of association between OHSS and composite adverse maternal outcome persisted when considering singleton pregnancies or those with severe disease.

CONCLUSIONS

Pregnancies complicated by OHSS are at high risk of adverse pregnancy outcome, especially PTB.

Genomics and Epigenomics of Gestational Diabetes Mellitus: Understanding the Molecular Pathways of the Disease Pathogenesis

One of the most common complications during pregnancy is gestational diabetes mellitus (GDM), hyperglycemia that occurs for the first time during pregnancy. The condition is multifactorial, caused by an interaction between genetic, epigenetic, and environmental factors. However, the underlying mechanisms responsible for its pathogenesis remain elusive. Moreover, in contrast to several common metabolic disorders, molecular research in GDM is lagging. It is important to recognize that GDM is still commonly diagnosed during the second trimester of pregnancy using the oral glucose tolerance test (OGGT), at a time when both a fetal and maternal pathophysiology is already present, demonstrating the increased blood glucose levels associated with exacerbated insulin resistance. Therefore, early detection of metabolic changes and associated epigenetic and genetic factors that can lead to an improved prediction of adverse pregnancy outcomes and future cardio-metabolic pathologies in GDM women and their children is imperative. Several genomic and epigenetic approaches have been used to identify the genes, genetic variants, metabolic pathways, and epigenetic modifications involved in GDM to determine its etiology. In this article, we explore these factors as well as how their functional effects may contribute to immediate and future pathologies in women with GDM and their offspring from birth to adulthood. We also discuss how these approaches contribute to the changes in different molecular pathways that contribute to the GDM pathogenesis, with a special focus on the development of insulin resistance.

Prevalence and Risk Factors Associated With Gestational Diabetes Mellitus Among Pregnant Women: A Cross-Sectional Study in Ghana

Gestational diabetes mellitus (GDM) is a global public health issue that have serious consequences on mother and her child’s health. However, limited data is available on the prevalence of GDM and its associated risk factors in Ghana. This study investigated the prevalence and associated risk factors of GDM among women attending selected antenatal clinics in Kumasi, Ghana. This cross-sectional study included 200 pregnant women who attended antenatal clinics from Three-selected health facilities in the Ashanti Region, Ghana. Women already diagnosed of GDM were identified through their medical records and were confirmed based on the criteria of the International Association of Diabetes and Pregnancy Study Groups (IADPSG), which uses a fasting blood glucose of ≥ 5.1 mmol/L. A well-structured questionnaire was used to collect data on socio-demographic, obstetric, clinical and lifestyle risk factors. Multivariate logistic regression models were used to determine the independent risk factors of GDM. The overall prevalence of GDM among study participants was 8.5%. GDM was prevalent among age 26 and 30 years (41.2%), married participants (94.1%) with basic education (41.2%) and being Akan by ethnicity (52.9%). Previous history of oral contraceptive use (aOR: 13.05; 95% CI: 1.43–119.23, p=0.023), previous history of preeclampsia (aOR: 19.30; 95% CI: 2.15-71.63; p=0.013) and intake of soda drinks (aOR: 10.05, 95% CI: 1.19–84.73, p=0.034) were found to be independent risk factors of GDM. The prevalence of GDM was found to be 8.5% and this was associated with the previous use of oral contraceptives, history of preeclampsia and intake of soda drinks. Public health education and dietary lifestyle modification may be required for pregnant women who are at risk of GDM.

Relation of maternal birthweight with early pregnancy obesity, gestational diabetes, and offspring macrosomia

This study aimed to investigate how maternal birthweight is related to early pregnancy obesity, gestational diabetes mellitus (GDM), and offspring birthweight. Females born term and singleton in Sweden between 1973 and 1995 (N = 305,893) were studied at their first pregnancy. Information regarding their birthweight, early pregnancy body mass index, and pregnancy complications was retrieved from the Swedish Medical Birth Register, as were data on their mothers and offspring. High maternal birthweights (2-3 standard deviation scores (SDS) and >3 SDS) were associated with greater odds of early pregnancy obesity, odds ratio (OR) 1.52 (95% confidence interval (CI) 1.42-1.63) and OR 2.06 (CI 1.71-2.49), respectively. A low maternal birthweight (<2 SDS) was associated with greater odds of GDM (OR 2.49, CI 2.00-3.12). No association was found between high maternal birthweight and GDM. A maternal birthweight 2-3 SDS was associated with offspring birthweight 2-3 SDS (OR 3.83, CI 3.44-4.26), and >3 SDS (OR 3.55, CI 2.54-4.97). Corresponding ORs for a maternal birthweight >3 SDS were 5.38 (CI 4.12-7.01) and 6.98 (CI 3.57-13.65), respectively. In conclusion, a high maternal birthweight was positively associated with early pregnancy obesity and offspring macrosomia. A low, but not a high maternal birthweight, was associated with GDM.

Differing risk factors for new onset and recurrent gestational diabetes mellitus in multipara women: a cohort study

OBJECTIVES

To assess whether recurrent gestational diabetes mellitus (GDM) and newly diagnosed GDM share similar risk factors.

METHODS

The study recruited a cohort of 10,151 multipara women with singleton pregnancy who delivered between 2016 and 2019 in Beijing, China. The prevalence of recurrent GDM and associated risk factors were analyzed between women with and without prior GDM history.

RESULTS

Eight hundred and seventy-five (8.6%) multipara women had a diagnosis of GDM during previous pregnancies. The prevalence of GDM and pre-gestational diabetes mellitus were 48.34% (423/875) and 7.89% (69/875) if the women were diagnosed with GDM during previous pregnancies, as compared to 16.00% (1484/9276) and 0.50% (46/9276) if the women were never diagnosed with GDM before. In women without a history of GDM, a variety of factors including older maternal age, higher pre-pregnancy body mass index (PPBMI), prolonged interval between the two pregnancies, higher early pregnancy weight gain, family history of type 2 diabetes mellitus (T2DM), maternal low birth weight, and higher early pregnancy glycemic and lipid indexes were generally associated with an increased risk of GDM at subsequent pregnancy. In women with a history of GDM, higher PPBMI, higher fasting glucose level and maternal birthweight ≥4000 g were independent risk factors for recurrent GDM.

CONCLUSIONS

GDM reoccurred in nearly half of women with a history of GDM. Risk factors for recurrent GDM and newly diagnosed GDM were different. Identifying additional factors for GDM recurrence can help guide clinical management for future pregnancies to prevent GDM recurrence.

Exposure to air pollutant mixture and gestational diabetes mellitus in Southern California: Results from electronic health record data of a large pregnancy cohort

BACKGROUND

Epidemiological findings are inconsistent regarding the associations between air pollution exposure during pregnancy and gestational diabetes mellitus (GDM). Several limitations exist in previous studies, including potential outcome and exposure misclassification, unassessed confounding, and lack of simultaneous consideration of air pollution mixtures and particulate matter (PM) constituents.

OBJECTIVES

To assess the association between GDM and maternal residential exposure to air pollution, and the joint effect of the mixture of air pollutants and PM constituents.

METHODS

Detailed clinical data were obtained for 395,927 pregnancies in southern California (2008-2018) from Kaiser Permanente Southern California (KPSC) electronic health records. GDM diagnosis was based on KPSC laboratory tests. Monthly average concentrations of fine particulate matter < 2.5 μm (PM_2.5), <10 μm (PM₁₀), nitrogen dioxide (NO₂), and ozone (O₃) were estimated using kriging interpolation of Environmental Protection Agency's routine monitoring station data, while PM_2.5 constituents (i.e., sulfate, nitrate, ammonium, organic matter and black carbon) were estimated using a fine-resolution geoscience-derived model. A multilevel logistic regression was used to fit single-pollutant models; quantile g-computation approach was applied to estimate the joint effect of air pollution and PM component mixtures. Main analyses adjusted for maternal age, race/ethnicity, education, median family household income, pre-pregnancy BMI, smoking during pregnancy, insurance type, season of conception and year of delivery.

RESULTS

The incidence of GDM was 10.9% in the study population. In single-pollutant models, we observed an increased odds for GDM associated with exposures to PM_2.5, PM₁₀, NO₂ and PM_2.5 constituents. The association was strongest for NO₂ [adjusted odds ratio (OR) per interquartile range: 1.176, 95% confidence interval (CI): 1.147-1.205)]. In multi-pollutant models, increased ORs for GDM in association with one quartile increase in air pollution mixtures were found for both kriging-based regional air pollutants (NO₂, PM_2.5, and PM₁₀, OR = 1.095, 95% CI: 1.082-1.108) and PM_2.5 constituents (i.e., sulfate, nitrate, ammonium, organic matter and black carbon, OR = 1.258, 95% CI: 1.206-1.314); NO₂ (78%) and black carbon (48%) contributed the most to the overall mixture effects among all krigged air pollutants and all PM_2.5 constituents, respectively. The risk of GDM associated with air pollution exposure were significantly higher among Hispanic mothers, and overweight/obese mothers.

CONCLUSION

This study found that exposure to a mixture of ambient PM_2.5, PM₁₀, NO₂, and PM_2.5 chemical constituents was associated with an increased risk of GDM. NO₂ and black carbon PM_2.5 contributed most to GDM risk.

Dynamic changes and early predictive value of branched-chain amino acids in gestational diabetes mellitus during pregnancy

OBJECTIVE

Branched-chain amino acids (BCAAs) are closely associated with type 2 diabetes mellitus, but their roles in gestational diabetes mellitus (GDM) are still controversial. This study aims to explore the dynamic changes of BCAAs during pregnancy and identify potential early biomarkers for GDM.

METHODS

This study is a nested case-control study involved 49 women with GDM and 50 age- and body mass index (BMI)-matched healthy pregnant women. The dynamic changes of valine (Val), isoleucine (Ile), and leucine (Leu) were detected in the first (8-12 weeks) and second trimesters (24-28 weeks) by liquid chromatography-mass spectrometry.

RESULTS

Serum Val, Ile, and Leu were higher in GDM patients than in controls in the first trimester. Compared with the first trimester, the serum Val, Ile, and Leu in GDM patients were decreased in the second trimester. In addition, Val, Ile, and Leu in the first trimester were the risk factors for GDM, and Ile presented a high predictive value for GDM. Ile + age (≥ 35) + BMI (≥ 24) exhibited the highest predictive value for GDM (AUC = 0.902, sensitivity = 93.9%, specificity = 80%).

CONCLUSION

Maternal serum Ile in the first trimester was a valuable biomarker for GDM. Ile combined with advanced maternal age and overweight may be used for the early prediction of GDM.

The relationship between hair metabolites, air pollution exposure and gestational diabetes mellitus: A longitudinal study from pre-conception to third trimester

BACKGROUND

Gestational diabetes mellitus (GDM) is a metabolic condition defined as glucose intolerance with first presentation during pregnancy. Many studies suggest that environmental exposures, including air pollution, contribute to the pathogenesis of GDM. Although hair metabolite profiles have been shown to reflect pollution exposure, few studies have examined the link between environmental exposures, the maternal hair metabolome and GDM. The aim of this study was to investigate the longitudinal relationship (from pre-conception through to the third trimester) between air pollution exposure, the hair metabolome and GDM in a Chinese cohort.

METHODS

A total of 1020 women enrolled in the Complex Lipids in Mothers and Babies (CLIMB) birth cohort were included in our study. Metabolites from maternal hair segments collected pre-conception, and in the first, second, and third trimesters were analysed using gas chromatography-mass spectrometry (GC-MS). Maternal exposure to air pollution was estimated by two methods, namely proximal and land use regression (LUR) models, using air quality data from the air quality monitoring station nearest to the participant's home. Logistic regression and mixed models were applied to investigate associations between the air pollution exposure data and the GDM associated metabolites.

RESULTS

Of the 276 hair metabolites identified, the concentrations of fourteen were significantly different between GDM cases and non-GDM controls, including some amino acids and their derivatives, fatty acids, organic acids, and exogenous compounds. Three of the metabolites found in significantly lower concentrations in the hair of women with GDM (2-hydroxybutyric acid, citramalic acid, and myristic acid) were also negatively associated with daily average concentrations of PM_2.5, PM₁₀, SO₂, NO₂, CO and the exposure estimates of PM_2.5 and NO_2, and positively associated with O₃.

CONCLUSIONS

This study demonstrated that the maternal hair metabolome reflects the longitudinal metabolic changes that occur in response to environmental exposures and the development of GDM.