Fasting and 2-hour plasma glucose, and HbA1c in pregnancy and the postpartum risk of diabetes among Chinese women with gestational diabetes

Is glucose pattern of OGTT associated with late-onset gestational diabetes and adverse pregnant outcomes?

BACKGROUND

The heterogeneity of oral glucose tolerance test (OGTT) patterns during pregnancy remains unclear. This study aims to identify latent OGTT patterns in pregnant women and investigate the high-risk population for late-onset gestational diabetes mellitus (GDM).

METHODS

This study including 17,723 participants was conducted from 2018 to 2021. Latent mixture modeling was used to identify subgroups. Modified Poisson regression was performed to explore the relationship between OGTT patterns and late-onset GDM or adverse perinatal outcomes.

RESULTS

Three distinct glucose patterns, high, medium, and low glucose levels (HG, MG, and LG patterns) were identified. The HG pattern represented 28.5% of the participants and 5.5% of them developed late-onset GDM. A five-fold higher risk of late-onset GDM was found in HG pattern than in LG pattern (relative risk [RR]: 5.17, 95% confidence interval [CI]: 3.38-7.92) after adjustment. Participants in HG pattern were more likely to have macrosomia, large for gestational age, preterm birth, and cesarean deliveries, with RRs of 1.59 (1.31-1.93), 1.55 (1.33-1.82), 1.30 (1.02-1.64) and 1.15 (1.08-1.23), respectively.

CONCLUSION

Three distinct OGTT patterns presented different risks of late-onset GDM and adverse perinatal outcomes, indicating that timely monitoring of glucose levels after OGTT should be performed in pregnant women with HG pattern.

Precision stratification of prognostic risk factors associated with outcomes in gestational diabetes mellitus: a systematic review

BACKGROUND

The objective of this systematic review is to identify prognostic factors among women and their offspring affected by gestational diabetes mellitus (GDM), focusing on endpoints of cardiovascular disease (CVD) and type 2 diabetes (T2D) for women, and cardiometabolic profile for offspring.

METHODS

This review included studies published in English language from January 1st, 1990, through September 30th, 2021, that focused on the above outcomes of interest with respect to sociodemographic factors, lifestyle and behavioral characteristics, traditional clinical traits, and 'omics biomarkers in the mothers and offspring during the perinatal/postpartum periods and across the lifecourse. Studies that did not report associations of prognostic factors with outcomes of interest among GDM-exposed women or children were excluded.

RESULTS

Here, we identified 109 publications comprising 98 observational studies and 11 randomized-controlled trials. Findings indicate that GDM severity, maternal obesity, race/ethnicity, and unhealthy diet and physical activity levels predict T2D and CVD in women, and greater cardiometabolic risk in offspring. However, using the Diabetes Canada 2018 Clinical Practice Guidelines for studies, the level of evidence was low due to potential for confounding, reverse causation, and selection biases.

CONCLUSIONS

GDM pregnancies with greater severity, as well as those accompanied by maternal obesity, unhealthy diet, and low physical activity, as well as cases that occur among women who identify as racial/ethnic minorities are associated with worse cardiometabolic prognosis in mothers and offspring. However, given the low quality of evidence, prospective studies with detailed covariate data collection and high fidelity of follow-up are warranted.

Predictors and risk factors of short-term and long-term outcomes among women with gestational diabetes mellitus (GDM) and their offspring: Moving toward precision prognosis?

As part of the American Diabetes Association Precision Medicine in Diabetes Initiative (PMDI) - a partnership with the European Association for the Study of Diabetes (EASD) - this systematic review is part of a comprehensive evidence evaluation in support of the 2 ^nd International Consensus Report on Precision Diabetes Medicine. Here, we sought to synthesize evidence from empirical research papers published through September 1 ^st , 2021 to evaluate and identify prognostic conditions, risk factors, and biomarkers among women and children affected by gestational diabetes mellitus (GDM), focusing on clinical endpoints of cardiovascular disease (CVD) and type 2 diabetes (T2D) among women with a history of GDM; and adiposity and cardiometabolic profile among offspring exposed to GDM in utero. We identified a total of 107 observational studies and 12 randomized controlled trials testing the effect of pharmaceutical and/or lifestyle interventions. Broadly, current literature indicates that greater GDM severity, higher maternal body mass index, belonging to racial/ethnic minority group; and unhealthy lifestyle behaviors would predict a woman's risk of incident T2D and CVD, and an unfavorable cardiometabolic profile among offspring. However, the level of evidence is low (Level 4 according to the Diabetes Canada 2018 Clinical Practice Guidelines for diabetes prognosis) largely because most studies leveraged retrospective data from large registries that are vulnerable to residual confounding and reverse causation bias; and prospective cohort studies that may suffer selection and attrition bias. Moreover, for the offspring outcomes, we identified a relatively small body of literature on prognostic factors indicative of future adiposity and cardiometabolic risk. Future high-quality prospective cohort studies in diverse populations with granular data collection on prognostic factors, clinical and subclinical outcomes, high fidelity of follow-up, and appropriate analytical approaches to deal with structural biases are warranted.

Early pregnancy glycaemia predicts postpartum diabetes mellitus

OBJECTIVE

To determine the association between early pregnancy glycaemia, as measured by glycosylated haemoglobin A1c (HbA1c) at the first prenatal visit, and persistent postpartum diabetes mellitus (DM).

STUDY DESIGN

All women first diagnosed with DM during pregnancy who had both HbA1c prior to 24 weeks and postpartum DM testing were included. The proportions of women with normal (<5.7%), prediabetic (5.7-6.4%) and elevated (≥6.5%) early HbA1c who tested positive for postpartum DM were compared. Test characteristics of HbA1c to predict persistent postpartum DM were calculated.

RESULTS

One hundred and twenty-one women met the study inclusion criteria. HbA1c was obtained at a median gestational age of 9 weeks. Twenty-two women (18.2%) had persistent postpartum DM, which was highly correlated with early HbA1c: 16 (73%) women had an elevated HbA1c, five (22.7%) women had a prediabetic HbA1c and only one (4.5%) woman had a normal HbA1c. Of 65 women with gestational DM and a normal early HbA1c, only one (1.5%) had persistent DM within the first year (negative predictive value 98.5%). Sixteen of 18 women with an elevated early HbA1c had persistent postpartum DM (positive predictive value 88.9%). These percentages were significant overall and between groups (p < 0.001). No clinical or demographic factors were highly predictive of postpartum DM.

CONCLUSIONS

Early pregnancy glycaemia, as measured by HbA1c at the first prenatal visit, is highly predictive of persistent postpartum DM, and may allow clinically important risk stratification to prioritize postpartum testing and care. Postpartum DM is rare amongst women with gestational DM who begin the pregnancy with a normal HbA1c, while postpartum DM is highly likely for those with an elevated HbA1c in early pregnancy. Nearly three-quarters of women who tested positive for DM post partum had an elevated HbA1c in early pregnancy, indicating that they had undiagnosed DM prior to conception.

Midwifery awareness of diabetes in pregnancy screening guidelines in Aotearoa New Zealand

OBJECTIVE

Effective and timely management of gestational diabetes mellitus (GDM) requires early detection. However, screening rates have been shown to be relatively low in New Zealand, despite the introduction of national screening guidelines in 2014 which indicate that all pregnant women should be screened. Thus, the aim of this study was to explore the awareness of the New Zealand Ministry of Health Diabetes in Pregnancy screening guidelines by New Zealand midwives.

DESIGN

A 24-question online survey based upon the New Zealand screening guidelines was distributed via New Zealand midwifery social media groups to explore the awareness of New Zealand midwives with regard to screening for diabetes in pregnancy. Free text comments were also allowed, these were broadly categorized and reviewed.

PARTICIPANTS

174 registered midwives in Aotearoa New Zealand completed the survey.

MEASUREMENTS AND FINDINGS

All participants responded that they routinely offer glycated haemoglobin screening for detection of undiagnosed pre-gestational diabetes, and 92.9% identified that this should occur prior to 20 weeks gestation (as per the national guidelines). However, less than two thirds of midwives thought that all women should be screened for GDM, with 18.2% indicating they would only do this if immediate risk factors were present. There also appeared to be some confusion over the time period for screening for GDM with 22.9% indicating that this should occur later than the guideline-recommended timepoint of 24-28 weeks gestation. Participants who identified as Māori and community-based midwives were most likely to screen for GDM 'only if risk factors were present'. Participants practicing for more than 6 years, those aged 45-54 years, and midwives identifying as Māori were most likely to screen for GDM after 28 weeks (though these did not reach statistical significance).

KEY CONCLUSIONS

The New Zealand Diabetes in Pregnancy screening guidelines do not appear to be well implemented in our sample group, particularly with regard to screening for GDM. This needs to be evaluated in a larger group of midwives, as education around the timeliness and importance of screening for all women may be required.

IMPLICATIONS FOR PRACTICE

A lack of appropriate or timely screening for GDM may mean that women are not being diagnosed or managed appropriately, which in turn may have implications for both mother and child.

Prevalence and Metabolic Predictors for Early Diagnosed Prediabetes in Women with Previous Gestational Diabetes: Observational Cohort Study

INTRODUCTION

Women with previous gestational diabetes (pGD) are at higher risk of prediabetes (PD) after delivery. The aim of this study was to determine the prevalence of and predictors for PD among women with pGD.

METHODS

The study included 186 women with pGD treated by lifestyle modification. After delivery, the women were divided into group A (n = 80) with PD and group B (n = 106) with normal glucose tolerance (NGT), defined by the results of the 2-h oral glucose tolerance test at 4-12 weeks after delivery. We recorded age, body mass index (BMI) at conception and after delivery, fasting glucose (FG), glycated hemoglobin (HbA1c), total cholesterol (TC), triglycerides (Tg), low density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c) and the Tg/HDL-c ratio measured in the third trimester of pregnancy.

RESULTS

Of the 186 women with pGD enrolled in the study, 43% showed prediabetes at 4-12 weeks after delivery, with 13.9% of these women showing impaired FG (IFG), 12.9% showing impaired glucose tolerance (IGT) and 16.2% with IFG/IGT. The groups differed in terms of age and BMI at conception and after delivery. In the third trimester of pregnancy, HbA1c was higher in women in group A than in those in group B (mean ± standard deviation: 5.6 ± 0.4 vs. 5.2 ± 0.3%; p < 0.001), while FG was comparable. Compared to women in group B, women in group A had higher TC (7.1 ± 0.8 vs. 6.6 ± 1.0 mmol/L), Tg (2.7 ± 0.9 vs. 2.1 ± 0.6 mmol/L) and LDL-c (4.7 ± 0.8 vs. 4.3 ± 1.0 mmol/L) (all p < 0.001), lower HDL-c (1.0 ± 0.2 vs. 1.4 ± 1.0; p < 0.001) and higher median Tg/HDL-c (5.4 [range 4.6-14.3] vs. 4.9 [range 1.1-11.5]; p < 0.001). Univariate analysis found an association between prediabetes and age, BMI at conception and after delivery, HbA1c, TC, LDL-c, HDL-c, Tg and Tg/HDL-c ratio. Of these variables, the multivariate analysis showed age (odds ratio [OR] 1.19; p < 0.001), HbA1c (OR 31.06; p < 0.001), Tg (OR 4.09; p < 0.001) and LDL-c (OR 2.00; p = 0.005) as predictors for prediabetes.

CONCLUSION

High prevalence of early diagnosed PD in women with pGD was accompanied by advanced age and higher BMI at conception and after delivery. Moreover, age, HbA1c, Tg and LDL-c were predictors for PD.

Oral Glucose Tolerance Test Results in Pregnancy Can Be Used to Individualize the Risk of Future Maternal Type 2 Diabetes Mellitus in Women With Gestational Diabetes Mellitus

OBJECTIVE

We aimed to quantify the risk of future maternal type 2 diabetes mellitus (T2DM) in women with gestational diabetes mellitus (GDM) based on the type and number of abnormal 75-g oral glucose tolerance test (OGTT) values and the diagnostic criteria used for the diagnosis of GDM.

RESEARCH DESIGN AND METHODS

We conducted a population-based retrospective cohort study of all nulliparous women with a live singleton birth who underwent testing for GDM using a 75-g OGTT in Ontario, Canada (2007-2017). We estimated the incidence rate (per 1,000 person-years), overall risk (expressed as adjusted hazard ratio [aHR]), and risk at 5 years after the index pregnancy of future maternal T2DM. Estimates were stratified by the type and number of abnormal OGTT values, as well as by the diagnostic criteria for GDM (Diabetes Canada [DC] vs. International Association of the Diabetes and Pregnancy Study Groups [IADPSG] criteria).

RESULTS

A total of 55,361 women met the study criteria. The median duration of follow-up was 4.4 (interquartile range 2.8-6.3; maximum 10.3) years. Using women without GDM as reference (incidence rate 2.18 per 1,000 person-years), women with GDM were at an increased risk of future T2DM; this risk was greater when using the DC compared with the IADPSG criteria (incidence rate 18.74 [95% CI 17.58-19.90] vs. 14.07 [95% CI 13.24-14.91] per 1,000 person-years, respectively). The risk of future maternal T2DM increased with the number of abnormal OGTT values and was highest for women with three abnormal values (incidence rate 49.93 per 1,000 person-years; aHR 24.57 [95% CI 21.26-28.39]). The risk of future T2DM was also affected by the type of OGTT abnormality: women with an abnormal fasting value had the greatest risk, whereas women with an abnormal 2-h value had the lowest risk (aHR 14.09 [95% CI 12.46-15.93] vs. 9.22 [95% CI 8.19-10.37], respectively). Similar findings to those described above were observed when the risk of T2DM at a fixed time point of 5 years after the index pregnancy was considered as the outcome of interest.

CONCLUSIONS

In women with GDM, individualized information regarding the future risk of T2DM can be provided based on the type and number of abnormal OGTT values, as well as the diagnostic criteria used for the diagnosis of GDM.

First trimester fasting glucose and glycated haemoglobin cut-offs associated with abnormal glucose homeostasis in the post-partum reclassification in women with hyperglycaemia in pregnancy

Hyperglycaemia first detected during pregnancy is either gestational diabetes mellitus (GDM) or previous undiagnosed diabetes. We aimed to study if there were a first trimester fasting glycaemia (FTG) and a glycated haemoglobin (HbA1c) cut-off values associated with type 2 diabetes mellitus (T2DM) or abnormal glucose homeostasis (AGH) at the post-partum oral glucose tolerance test (OGTT) reclassification. We retrospectively studied a group of pregnant women from the Portuguese National Registry of GDM. Receiver-operating characteristic (ROC) curves were used to determine the best FTG and HbA1c cut-offs to predict T2DM and AGH. We studied 4068 women. The area under the ROC curves (AUC) for the association with T2DM was 0.85 (0.80-0.90) for FTG and 0.85 (0.80-0.91) for HbA1c. The best FTG cut-off for association with T2DM was 99 mg/dL: sensitivity 77.4%, specificity 74.3%, positive predictive value (PPV) 4.8%, and negative predictive value (NPV) 99.5%. The best HbA1c cut-off for association with T2DM was 5.4%: sensitivity 79.0%, specificity 80.1%, PPV 5.7%, and NPV 99.6%. The AUC for the association of FTG and HbA1c with AGH were 0.73 (0.70-0.76) and 0.71 (0.67-0.74), respectively. The best FTG cut-off for predicting AGH was 99 mg/dL: sensitivity 59.4%, specificity 76.2%, PPV 17.0%, and NPV 95.8%. The best HbA1c cut-off was 5.4%: sensitivity 48.7%, specificity 81.5%, PPV 17.8%, and NPV 95.1%. We suggest an FTG of 99 mg/dL and an HbA1c of 5.4% as the best cut-offs below which T2DM is unlikely to be present. Almost all patients with FTG < 99 mg/dL and HbA1c < 5.4% did not reclassify as T2DM. These early pregnancy cut-offs might alert the physician for the possibility of a previous undiagnosed diabetes and alert them to the importance of testing for it after delivery.

Risk of Developing Type 2 Diabetes Mellitus in South Asian Women with History of Gestational Diabetes Mellitus: A Systematic Review and Meta-Analysis

BACKGROUND

Gestational diabetes mellitus (GDM) and type 2 diabetes mellitus (T2DM) represent two different components of the spectrum of diabetes mellitus (DM). Women with GDM have a high chance of developing T2DM in later life and this relative risk depends on a number of factors including ethnicity.

AIM

To compare and estimate the risk of developing T2DM in South Asian women with a history of GDM compared to those without a history of GDM.

METHODS

This is a systematic review of PubMed and MEDLINE articles reporting the progression of GDM to T2DM that were published in English from 2000 to 2020. We performed meta-analysis to calculate risk ratios (RR).

RESULTS

We selected 6 studies considering the inclusion and exclusion criteria after sorting 25 full-text articles. Of the 44165 South Asian women assessed, 3095 had GDM and 41070 were without GDM. 995 women in GDM group and 1525 women in non-GDM group had developed T2DM. The RR of women with GDM over non-GDM in developing T2DM was 10.81 (95% confidence interval (CI): 7.61-15.35) suggesting that women with GDM are at 10.81 times more risk of developing T2DM than non-GDM. The cumulative incidence of T2DM in GDM group was 17.34% at 5 years of follow-up and 33% at more than 10 years of follow-up.

CONCLUSION

The risk of developing T2DM in later life is higher in South Asian women with GDM than without GDM. Therefore, lifestyle and pharmacological interventions, patient communication, timely screening, and long-term follow-up of GDM patients are important to reduce the risk.

Association between the antepartum oral glucose tolerance test and the risk of future diabetes mellitus among women with gestational diabetes: A systematic review and meta-analysis

OBJECTIVES

The antepartum oral glucose tolerance test (OGTT) has re-emerged as associated with risk of diabetes among women with gestational diabetes (GDM). This systematic review summarized evidence on associations between antepartum OGTT and risk of diabetes in GDM (PROSPERO CRD42018100316).

METHODS

MEDLINE, EMBASE, Web of Science, and CENTRAL were searched from January 1, 1982 to February 2020. Studies assessing associations between antepartum OGTT and risk of diabetes among women with GDM were included. Data on study characteristics, participants, OGTT values, and diabetes outcomes were extracted. Estimates on the association between antepartum OGTT and diabetes at follow-up were recorded. Pooled odds ratios for developing diabetes were calculated by study design.

FINDINGS AND CONCLUSIONS

Of 6423 citations, 17 studies were included. Both elevated fasting blood glucose (FBG; OR: 3.62 ([95% CI 1.30, 10.12], I² = 36%, p < 0.05)) and 2 h OGTT (OR: 3.96 [1.17, 13.40], I² = 87%, p < 0.05) were associated with diabetes. These associations were attenuated (FBG: OR: 1.91 ([95% CI 0.80, 24.54], I² = 83%, p = NS) and 1.58 ([95% CI 0.92, 2.74] I² = 83%, p = NS) for prospective and retrospective data, respectively; 2 h OGTT: ORa: 1.95 ([95% CI 0.43, 8.93], I² = 94%, p = NS)) after adjustments for common confounders. Further research is needed before clinical recommendations can be made.

β-Cell function or insulin resistance was associated with the risk of type 2 diabetes among women with or without obesity and a history of gestational diabetes

INTRODUCTION

To evaluate the single association of postpartum β-cell dysfunction and insulin resistance (IR), as well as different combinations of postpartum β-cell dysfunction, IR, obesity, and a history of gestational diabetes mellitus (GDM) with postpartum type 2 diabetes risk.

RESEARCH DESIGN AND METHODS

The study included 1263 women with prior GDM and 705 women without GDM. Homeostatic model assessment was used to estimate homeostatic model assessment of β-cell secretory function (HOMA-%β) and homeostatic model assessment of insulin resistance (HOMA-IR).

RESULTS

Multivariable-adjusted ORs of diabetes across quartiles of HOMA-%β and HOMA-IR were 1.00, 1.46, 2.15, and 6.25 (p_trend <0.001), and 1.00, 2.11, 5.59, and 9.36 (p_trend <0.001), respectively. Women with IR only had the same diabetes risk as women with β-cell dysfunction only. Obesity, together with IR or β-cell dysfunction, had a stronger effect on diabetes risk. This stronger effect was also found for a history of GDM with IR or β-cell dysfunction. Women with three risk factors, including obesity, a history of GDM and β-cell dysfunction/IR, showed the highest ORs of diabetes.

CONCLUSIONS

β-cell dysfunction or IR was significantly associated with postpartum diabetes. IR and β-cell dysfunction, together with obesity and a history of GDM, had the highest ORs of postpartum diabetes risk.

Effects of obesity and a history of gestational diabetes on the risk of postpartum diabetes and hyperglycemia in Chinese women: Obesity, GDM and diabetes risk

OBJECTIVE

To evaluate the independent or combined effects of gestational diabetes (GDM) and pre-pregnancy and postpartum BMI on the odds of postpartum diabetes and hyperglycemia.

METHODS

The study samples included 1263 women with prior GDM and 705 women without GDM. Postpartum 1-7 years diabetes was diagnosed by the standard oral glucose tolerance test.

RESULTS

The multivariable-adjusted odds ratios among women with prior GDM, compared with those without it, were 7.52 for diabetes and 2.27 for hyperglycemia. The multivariable-adjusted odds ratios at different postpartum BMI levels (<24, 24-27.9, and ≥ 28 kg/m²) were 1.00, 2.80, and 8.08 for diabetes (P_trend < 0.001), and 1.00, 2.10, and 4.42 for hyperglycemia (P_trend < 0.001), respectively. Women with high body fat (≥31.9%) or abdominal obesity (≥85 cm) had a 2.7-6.9-fold higher odds ratio for diabetes or hyperglycemia. Women with both obesity and prior GDM had the highest risk of diabetes or hyperglycemia compared with non-obese women without GDM. Non-obese women with prior GDM had the same risk of diabetes and hyperglycemia as non-GDM women with obesity. When using Cox regression models, the results were very close to those using logistic regression models.

CONCLUSIONS

Maternal prior GDM and pre-pregnancy or postpartum obesity contribute equally to postpartum diabetes and hyperglycemia risk.

High risk of metabolic syndrome after delivery in pregnancies complicated by gestational diabetes

AIMS

To investigate the risk of postpartum metabolic syndrome in women with GDM compared with those without GDM in a Chinese population.

METHODS

Tianjin GDM observational study included 1263 women with a history of GDM and 705 women without GDM. Multivariate logistic regression was used to assess risks of postpartum metabolic syndrome between women with and without GDM. Postpartum metabolic syndrome was diagnosed by two commonly used criteria.

RESULTS

During a mean 3.53 years of follow up, 256 cases of metabolic syndrome were identified by using the NCEP ATPIII criteria and 244 cases by using the IDF criteria. Multivariable-adjusted odds ratios of metabolic syndrome in women with GDM compared with those without GDM were 3.66 (95% confidence interval [CI] 2.02-6.63) for NCEP ATPIII criteria and 3.90 (95% CI 2.13-7.14) for IDF criteria. Women with GDM had higher multivariable-adjusted odds ratios of central obesity, hypertriglyceridemia, and high blood pressure than women without GDM. The multivariable-adjusted odds ratios of low HDL cholesterol and hyperglycemia were not significant between women with and without GDM, however, the multivariable-adjusted odds ratio of hyperglycemia became significant when we used the modified criteria.

CONCLUSIONS

The present study indicated that women with prior GDM had significantly higher risks for postpartum metabolic syndrome, as well as its individual components.

Predictors of Insulin Treatment During Pregnancy and Abnormal Postpartum Glucose Metabolism in Patients with Gestational Diabetes Mellitus

BACKGROUND

To investigate the potential predictors of insulin treatment during pregnancy and abnormal postpartum glucose metabolism in gestational diabetes mellitus (GDM).

METHODS

A total of 534 patients with GDM, who were diagnosed based on 75 g oral glucose tolerance test (OGTT) during pregnancy, were divided into the diet group (n=354) and insulin group (n=180) according to the treatment of hyperglycemia in pregnancy. Based on 75 g OGTT after delivery, 178 of the 534 patients were divided into the normal glucose tolerance (NGT; n=104) and the abnormal glucose tolerance (AGT; n=74) groups. Characteristics and metabolic indicators were compared. Logistic regression analysis was developed to assess the potential predictors of insulin treatment and abnormal postpartum glucose metabolism. Receiver operating characteristic curve was performed to determine the cut-off values.

RESULTS

Fasting plasma glucose (FPG), 1 h plasma glucose, and hemoglobin A1c (HbA1c) at GDM diagnosis were higher in the insulin group compared with the diet group (P <0.05). FPG, 1 h plasma glucose, HbA1c, maternal age, pre-gestational weight and maximum weight, pre-gestational body mass index, maternal birth weight, family history of diabetes in first-degree relatives, acanthosis nigricans, and prenatal weight were risk factors for insulin treatment (P <0.05), and the cut-offs of FPG, 1 h plasma glucose and HbA1c were 5.7 mmol/L, 11.4 mmol/L and 5.3%. Simultaneously, FPG at GDM diagnosis, insulin treatment during pregnancy, maternal age, family history of diabetes in first-degree relatives, acanthosis nigricans, and prenatal weight were risk factors of abnormal postpartum glucose metabolism (P <0.05), and the cut-off of FPG was 5.7 mmol/L.

CONCLUSION

Patients with FPG >5.7 mmol/L, 1 h plasma glucose >11.4 mmol/L, or HbA1c >5.3% at GDM diagnosis required insulin treatment, and patients with FPG >5.7 mmol/L had a greater risk of abnormal postpartum glucose metabolism. FPG at GDM diagnosis was the most important predictor.

Clinical and biochemical approach to predicting post-pregnancy metabolic decompensation

The prevalence of gestational diabetes in the developed world is increased and parallels that of obesity. Apart from the maternal and fetal complications occurring during pregnancy, GDM is characterized by a high subsequent risk of type 2 diabetes, metabolic syndrome, and cardiovascular disease. In this paper, we outline the different factors to consider in assessing the future risk of diabetes developing in women with a history of GDM. Looking at the modifiable risk factors, it is worth noting that promoting a healthy diet and lifestyle before (physical activity), during and after pregnancy (breast feeding) in women of fertile age are fundamental to the success of efforts to reduce the burden of diabetes in these young people.

Evidence for the utility of antenatal HbA1c to predict early postpartum diabetes after gestational diabetes in South Africa

Aim To evaluate antenatal HbA1c at diagnosis and in the 4 weeks preceding delivery to predict early postpartum diabetes mellitus (DM) in women with Gestational Diabetes Mellitus (GDM). Methods Seventy-eight women with GDM were prospectively assessed. The ability of HbA1c at GDM diagnosis (t1) and in the 4 weeks preceding delivery (t2) to predict DM 6-12 weeks after delivery was investigated. Glucose assessment was performed between November 1, 2015, and November 1, 2016 at Tygerberg Hospital (TH), Cape Town, South Africa (SA). Individuals with known pre-existing diabetes were excluded. Results HbA1c of 6.2% (44 mmol/mol) and 6.5% (48 mmol/mol) at t1 predicted DM with sensitivities of 95% and 90% and specificities of 62% and 70% respectively. At t2 the best cut-off for HbA1c, in accordance with t1, was also 6.2% (44 mmol/mol; sensitivity 92%, specificity 56%). Nineteen of the 29 women with suspected pre-gestational DM had HbA1c levels ≥ 6.5% (48 mmol/mol) at t1. The increased risk for postpartum DM with HbA1c ≥ 6.2% (44 mmol/mol) was four-fold (OR 3.97 CI 2.08-7.59p < 0.001) at t1 and five-fold (OR 5.08 CI 1.60-16.25 p = 0.006) at t2. Conclusion HbA1c lower than 6.5% (48 mmol/mol) predicts postpartum DM in women with GDM. HbA1c can serve as instrument to improve postpartum follow-up.

Gestational diabetes with diabetes and prediabetes risks: a large observational study

AIMS

To compare risks of early postpartum diabetes and prediabetes in Chinese women with and without gestational diabetes mellitus (GDM) during pregnancy.

SUBJECTS AND METHODS

Tianjin GDM observational study included 1263 women with a history of GDM and 705 women without GDM who participated in the urban GDM universal screening survey by using World Health Organization's criteria. Postpartum diabetes and prediabetes were identified after a standard oral glucose tolerance test. Cox proportional hazards regression was used to assess risks of postpartum diabetes and prediabetes between women with and without GDM.

RESULTS

During a mean follow-up of 3.53 years postpartum, 90 incident cases of diabetes and 599 incident cases of prediabetes were identified. Multivariable-adjusted hazard ratios among women with prior GDM, compared with those without it, were 76.1 (95% CI: 23.6-246) for diabetes and 25.4 (95% CI: 18.2-35.3) for prediabetes. When the mean follow-up extended to 4.40 years, 121 diabetes and 616 prediabetes cases were identified. Women with prior GDM had a 13.0-fold multivariable-adjusted risk (95% CI: 5.54-30.6) for diabetes and 2.15-fold risk (95% CI: 1.76-2.62) for prediabetes compared with women without GDM. The positive associations between GDM and the risks of postpartum diabetes and prediabetes were significant and persistent when stratified by younger and older than 30 years at delivery and normal weight and overweight participants.

CONCLUSIONS

The present study indicated that women with prior GDM had significantly increased risks for postpartum diabetes and prediabetes, with the highest risk at the first 3-4 years after delivery, compared with those without GDM.

Postpartum risk of diabetes and predictive factors for glucose intolerance in East Asian women with gestational diabetes

AIMS

Women with a history of gestational diabetes mellitus (GDM) are likely to develop postpartum diabetes mellitus (DM). We examined women in the early stages of pregnancy who were at high risk of postpartum DM progression to establish a follow-up method for early detection.

METHODS

We performed the oral glucose tolerance test (OGTT) and identified predictive factors for postpartum impaired glucose tolerance (IGT) or DM in 77 women after GDM, for 2 years after delivery, retrospectively. Cutoff values for each factor were determined. We classified these women with GDM into four groups using these predictive factors and evaluated postpartum glucose intolerance (GI) in each group.

RESULTS

In total, 44.1% of the women with a GDM history had developed postpartum GI within 2 years. We determined three risk factors for postpartum GI: elevated glucose level 120 min after a 75-g OGTT (Glu120), elevated glycated hemoglobin (HbA1c) level at diagnosis, and perinatal complications. The cutoff Glu120 and the HbA1c level were 155 mg/dl and 5.3% (34 mmol/mol), respectively. Type 2 DM developed in 53.8% of women, and IGT developed in 38.5% of women within 2 years in groups with high Glu120 and high HbA1c.

CONCLUSIONS

High-risk groups require careful follow-up observation.

One-year weight losses in the Tianjin Gestational Diabetes Mellitus Prevention Programme: A randomized clinical trial

AIMS

To report the weight loss findings after the first year of a lifestyle intervention trial among women with gestational diabetes mellitus (GDM).

METHODS

A total of 1180 women with GDM were randomly assigned (1:1) to receive a 4-year lifestyle intervention (intervention group, n = 586) or standard care (control group, n = 594) between August 2009 and July 2011. Major elements of the intervention included 6 face-to-face sessions with study dieticians and two telephone calls in the first year, and two individual sessions and two telephone calls in each subsequent year.

RESULTS

Among 79% of participants who completed the year 1 trial, mean weight loss was 0.82 kg (1.12% of initial weight) in the intervention group and 0.09 kg (0.03% of initial weight) in the control group (P = .001). In a prespecified subgroup analysis of people who completed the trial, weight loss was more pronounced in women who were overweight (body mass index ≥24 kg/m² ) at baseline: mean weight loss 2.01 kg (2.87% of initial weight) in the intervention group and 0.44 kg (0.52% of initial weight) in the control group (P < .001). Compared with those in the control group, women in the intervention group had a greater decrease in waist circumference (1.76 cm vs 0.73 cm; P = .003) and body fat (0.50% vs 0.05% increase; P = .001).

CONCLUSION

The 1-year lifestyle intervention led to significant weight losses after delivery in women who had GDM, and the effect was more pronounced in women who were overweight at baseline.

Colostrum and mature breast milk analysis of serum irisin and sterol regulatory element-binding proteins-1c in gestational diabetes mellitus

Background: We aimed to evaluate irisin and SREBP-1c levels in serum, colostrum and mature breast milk in women with and without gestational diabetes (GDM); and to relate them with maternal glucose, lipid profile and weight status of babies. Methods: GDM positive women (n = 33) and normal glucose tolerant women (NGT) (n = 33) were recruited. Maternal blood samples were collected at 28th week of gestation and later at 6-week post-partum while breast milk samples of the lactating mothers were collected within 72 hours of birth (colostrum) and at 6 weeks post-partum (mature milk). Irisin and SREBP-1c levels were analyzed by commercially available ELISA kits for all maternal samples. Results: Lower levels of irisin were seen in serum, colostrum and mature breast milk of GDM females (p < .01). SREBP-1c profile showed a similar trend of low serum levels in GDM, however, they were undetectable in colostrum and mature breast milk. Weak to moderate correlations of serum irisin with BMI (r = 0.439; p < .001), GTT 0 hours (r = 0.403; p = .01), HbA1c (r = -0.312; p = .011), Fasting blood glucose (r = 0.992; p = .008), and baby weight at birth (r = 0.486; p < .001). Colostrum and mature breast milk irisin showed positive associations with baby weight at 6 weeks (r = 0.325; p = .017; r = 0.296; p = .022, respectively). Serum SREBP-1c at 6 weeks correlated with random blood glucose (r = 0.318; p = .009), and HbA1c (r= -0.292; p = .011). All correlations were lost once we adjusted for maternal BMI. Conclusions: Low irisin and SREBP1-c levels may favor development of GDM in pregnant subjects. Further, low mature breast milk levels may act as a continued stressor from fetal to infant life as long as breast-feeding is continued. Further studies are required to identify the mechanistic relationship between these biomarkers and GDM.

Risk factors associated with the development of postpartum diabetes in Japanese women with gestational diabetes

BACKGROUND

Although the onset of gestational diabetes (GDM) is known to be a significant risk factor for the future development of type 2 diabetes, this risk specifically in women with GDM diagnosed by the International Association of Diabetes and Pregnancy Study Group (IADPSG) criteria has not yet been thoroughly investigated. This study was performed to investigate the risk factors associated with the development of postpartum diabetes in Japanese women with a history of GDM, and the effects of the differences in the previous Japanese criteria and the IADPSG criteria.

METHODS

This retrospective cohort study included Japanese women with GDM who underwent at least one postpartum oral glucose tolerance test (OGTT) between 2003 and 2014. Cases with overt diabetes in pregnancy were excluded. We investigated the risk factors including maternal baseline and pregnancy characteristics associated with the development of postpartum diabetes.

RESULTS

Among 354 women diagnosed with GDM during the study period, 306 (86%) (116/136 [85.3%] and 190/218 [87.2%] under the previous criteria and the IADPSG criteria, respectively) who underwent at least 1 follow-up OGTT were included in the study. Thirty-two women (10.1%) developed diabetes within a median follow-up period of 57 weeks (range, 6-292 weeks). Eleven (9.5%) and 21 (11.1%) were diagnosed as GDM during pregnancy based on the previous Japanese criteria and the IADPSG criteria, respectively, which did not significantly differ between those criteria. A multivariate logistic regression analysis revealed that HbA1c and 2-h plasma glucose (PG) at the time of the diagnostic OGTT during pregnancy were independent predictors of the development of diabetes after adjusting for confounders. The adjusted relative risk of HbA1c ≥5.6% for the development of diabetes was 4.67 (95% confidence interval, 1.53-16.73), while that of 2-h PG ≥183 mg/dl was 7.02 (2.51-20.72).

CONCLUSIONS

A modest elevation of the HbA1c and 2-h PG values at the time of the diagnosis of GDM during pregnancy are independent predictors of the development of diabetes during the postpartum period in Japanese women with a history of GDM. The diagnostic criteria did not affect the incidence of postpartum diabetes.

HbA1c as a predictor of diabetes after gestational diabetes mellitus

AIM

We wanted to investigate third-trimester HbA1c as a predictor of diabetes after gestational diabetes mellitus (GDM).

METHODS

Women with GDM were followed up prospectively for five years from pregnancy to detect the development of diabetes. The ability of HbA1c to predict diabetes was evaluated with receiver-operating characteristic (ROC) curves and logistic regression analysis.

RESULTS

By five years, 73 of 196 women had been diagnosed with diabetes. An optimal cut-off point for HbA1c of 36mmol/mol (5.4%) could predict diabetes with 45% sensitivity and 92% specificity. For HbA1c ≥39mmol/mol (≥5.7%), sensitivity, specificity, and positive predictive value were 30%, 97%, and 91%, respectively. In logistic regression analysis, adjusting for the diagnostic glucose concentration during pregnancy, HbA1c levels in the upper quartile (≥36mmol/mol) were associated with a 5.5-fold increased risk of diabetes.

CONCLUSION

Third-trimester HbA1c levels in the pre-diabetes range revealed women with post-partum diabetes with high specificity and high positive predictive value. HbA1c testing could be used as a strategy to select high-risk women for lifestyle interventions aimed at prevention of diabetes starting during pregnancy. The results should encourage further validation in other populations using new diagnostic criteria for GDM.