Selective versus universal screening for gestational diabetes mellitus: an evaluation of predictive risk factors

Association of common variants of TCF7L2 and PCSK2 with gestational diabetes mellitus in West Bengal, India

The genetic etiology of gestational diabetes mellitus (GDM) was suggested to overlap with type-2 diabetes(T2D). Transcription factor 7-like 2 (TCF7L2) and Proprotein Convertase Subtilisin/Kexin type 2 (PCSK2) are T2D susceptibility genes of the insulin synthesis/processing pathway. We analyzed associations of TCF7L2 and PCSK2 variants with GDM risk and evaluated their potential impact on impaired insulin processing in an eastern Indian population. The study included 114 GDM (case) and 228 non-GDM pregnant women (control). rs7903146, rs4132670, rs12255372 of TCF7L2, and rs2269023 of PCSK2 were genotyped by PCR-RFLP, and genotype distributions were compared between case and control. Fasting serum proinsulin and C-peptide levels were measured by ELISA and the Proinsulin/C-peptide ratio was considered an indicator of proinsulin conversion. Significantly higher frequency of risk allele (T) of rs12255372 (p = 0.02, OR = 2.0, 95%CI = 1.11-3.64) and rs4132670 (p = 0.002, OR = 2.26, 95%CI = 1.32-3.87) of TCF7L2 was found in GDM cases than non-GDM controls; TT genotype was associated with significantly increased disease risk. In rs7903146 (TCF7L2) and rs2269023 (PCSK2), although the frequency of risk allele (T) was not significantly higher in cases than controls, an association of TT for both variants remained significant with higher GDM risk in the recessive model. Increased serum pro-insulin and proinsulin:c-peptide ratio was found in GDM than non-GDM women and the phenomenon showed significant association with careers of risk alleles for TCF7L2 variants. In conclusion, TCF7L2 and PCSK2 variants are related to GDM risk in the studied population and hence may serve as potential biomarkers for assessing the disease risk. TCF7L2 variants contribute to impaired insulin processing.

Exposure to per- and polyfluoroalkyl substances in early pregnancy, risk of gestational diabetes mellitus, potential pathways, and influencing factors in pregnant women: A nested case-control study

Although previous studies have reported an association between maternal serum perfluoroalkyl substance (PFAS) exposure and gestational diabetes mellitus (GDM) risk, results have been inconsistent. Few studies have focused on the combined effects of emerging and legacy PFASs on glucose homeostasis while humans are always exposed to multiple PFASs simultaneously. Moreover, the potential pathways by which PFAS exposure induces GDM are unclear. A total of 295 GDM cases and 295 controls were enrolled from a prospective cohort of 2700 pregnant women in Shanghai, China. In total, 16 PFASs were determined in maternal spot serum samples in early pregnancy. We used conditional logistic regression, multiple linear regression, and Bayesian kernel machine regression (BKMR) to examine individual and joint effects of PFAS exposure on GDM risk and oral glucose tolerance test outcomes. The mediating effects of maternal serum biochemical parameters, including thyroid and liver function were further assessed. Maternal perfluorooctanoic acid (PFOA) exposure was associated with an increased risk of GDM (odds ratio (OR) = 1.68; 95% confidence interval (95% CI): 1.10, 2.57), consistent with higher concentrations in GDM cases than controls. Based on mediation analysis, an increase in the free triiodothyronine to free thyroxine ratio partially explained the effect of this association. For continuous glycemic outcomes, positive associations were observed between several PFASs and 1-h and 2-h glucose levels. In BKMR, PFAS mixture exposure showed a positive trend with GDM incidence, although the CIs were wide. These associations were more pronounced among women with normal pre-pregnancy body mass index (BMI). Mixed PFAS congeners may affect glucose homeostasis by increasing 1-h glucose levels, with perfluorononanoic acid found to be a main contributor. Exposure to PFASs was associated with increased risk of GDM and disturbance in glucose homeostasis, especially in normal weight women. The PFAS-associated disruption of maternal thyroid function may alter glucose homeostasis.

Placental Growth Factor and Pregnancy-Associated Plasma Protein-A as Potential Early Predictors of Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is one of the most common pregnancy complications and one of the main causes of adverse pregnancy outcomes. An early diagnosis of GDM is of fundamental importance in clinical practice. However, the major professional organizations recommend universal screening for GDM, using a 75 g oral glucose tolerance test at 24-28 weeks of gestation. A selective screening at an early stage of pregnancy is recommended only if there are maternal risk factors for diabetes. As a result, the GDM diagnosis is often delayed and established after the appearance of complications. The manifestation of GDM is directly related to insulin resistance, which is closely associated with endothelial dysfunction. The placenta, the placental peptides and hormones play a pivotal role in the manifestation and progression of insulin resistance during pregnancy. Recently, the placental growth factor (PlGF) and plasma-associated protein-A (PAPP-A), have been shown to significantly affect both insulin sensitivity and endothelial function. The principal function of PAPP-A appears to be the cleavage of circulating insulin-like growth factor binding protein-4 while PlGF has been shown to play a central role in the development and maturation of the placental vascular system and circulation. On one hand, these factors are widely used as early predictors (11-13 weeks of gestation) of complications during pregnancy, such as preeclampsia and fetal aneuploidies, in most countries. On the other hand, there is increasing evidence for their predictive role in the development of carbohydrate disorders, but some studies are rather controversial. Therefore, this review aims to summarize the available literature about the potential of serum levels of PlGF and PAPP-A as early predictors in the diagnosis of GDM.

The Role of Placental Growth Factor in the Prediction of Carbohydrate and Thyroid Disorders during Pregnancy

Background and objectives: To assess whether placental growth factor (PlGF) levels may have a predictive value for the onset of gestational diabetes mellitus (GDM) and thyroid dysfunction during pregnancy. Materials and Methods: This single-center retrospective analysis was conducted at the Specialized Hospital for Active Treatment in Obstetrics and Gynecology “Dr. Shterev”, Sofia, Bulgaria, from December 2017 to December 2019. Using pregnant women’s electronic records, we analyzed and compared the data of 412 women diagnosed with GDM and 250 women without evidence for carbohydrate disorders. Thyroid function was tested in all patients at the time of performing GDM screening. The following measurements were compared and assessed: body mass index (BMI), fasting blood glucose levels, thyroid-stimulating hormone levels (TSH), free thyroxine, and triiodothyronine (FT4 and FT3) levels, and serum placental growth factor (PlGF). The sensitivity and specificity of PlGF as a predictive marker for GDM and thyroid dysfunction were analyzed using receiver operating characteristic (ROC) curves. Results: There were no significant differences between GDM and control groups in terms of age and BMI (p > 0.05). In patients with established GDM, the PlGF corrected multiple of the median (MoM) was significantly higher compared to the control group (0.9 vs. 0.7, p < 0.001). The ROC-AUC for the prediction of GDM and thyroid dysfunction during pregnancy was 0.68 (95% CI 0.64–0.72) and 0.61 (95% CI 0.57–0.65), respectively. Conclusions: Our results underscore the potential role of PlGF as a biomarker in the prediction and diagnosis of GDM and thyroid dysfunction during pregnancy.

What is known and what remains unresolved regarding gestational diabetes mellitus (GDM)

Gestational diabetes mellitus (GDM) has become a major public health issue and one of the most discussed topics in contemporary obstetrics. Due to rising prevalence of GDM worldwide impact and importance of this medical condition in good quality antenatal care is growing. GDM is associated with serious adverse perinatal outcomes and unfavorable long-term health consequences for both, mother and her child. Despite a great amount of knowledge accumulated regarding GDM, medical community remains indecisive and still debates the most appropriate diagnostic strategy, screening policy, and treatment options for pregnancies complicated with GDM. These unresolved issues generate controversies, motivate further research and contribute to the growing interest surrounding GDM. In this review we will discuss and try to explain some of them.

Prediction of gestational diabetes based on nationwide electronic health records

Gestational diabetes mellitus (GDM) poses increased risk of short- and long-term complications for mother and offspring^1-4. GDM is typically diagnosed at 24-28 weeks of gestation, but earlier detection is desirable as this may prevent or considerably reduce the risk of adverse pregnancy outcomes^5,6. Here we used a machine-learning approach to predict GDM on retrospective data of 588,622 pregnancies in Israel for which comprehensive electronic health records were available. Our models predict GDM with high accuracy even at pregnancy initiation (area under the receiver operating curve (auROC) = 0.85), substantially outperforming a baseline risk score (auROC = 0.68). We validated our results on both a future validation set and a geographical validation set from the most populated city in Israel, Jerusalem, thereby emulating real-world performance. Interrogating our model, we uncovered previously unreported risk factors, including results of previous pregnancy glucose challenge tests. Finally, we devised a simpler model based on just nine questions that a patient could answer, with only a modest reduction in accuracy (auROC = 0.80). Overall, our models may allow early-stage intervention in high-risk women, as well as a cost-effective screening approach that could avoid the need for glucose tolerance tests by identifying low-risk women. Future prospective studies and studies on additional populations are needed to assess the real-world clinical utility of the model.

Analysis of the correlation of gestational diabetes mellitus and peripheral ferritin with iron levels in early pregnancy

BACKGROUND

The aim of this study was to investigate the relationship of serum iron and ferritin concentrations in early pregnancy with gestational diabetes mellitus (GDM) complicated in pregnant metaphase through detecting the serum iron and ferritin concentrations in early pregnancy of normal pregnant women, so as to provide new ideas for the early detection and prevention of GDM.

METHODS

Spontaneously pregnant women with single fetus receiving prenatal routine examination in our hospital from December 2014 to October 2016 were selected. They were in good health before with normal fasting blood-glucose in early pregnancy without anemia during pregnancy and any medication history. The serum iron and ferritin concentrations were measured at 12 gestational weeks, the fasting blood-glucose was detected at 12 weeks of pregnancy, and 75g oral glucose tolerance test was performed at 24-26 weeks. According to the results of oral glucose tolerance test, the pregnant women were divided into GDM group (N.=52) and normal control group (N.=310). The detection results of pregnant women in the two groups were statistically analyzed.

RESULTS

The serum ferritin and iron levels at 12 gestational weeks in GDM group were higher than those in normal pregnancy group (P<0.05). The cut-off values of serum ferritin and iron at 12 gestational weeks in the prediction of GDM were 67.8 μg/L and 52.9 mmol/L.

CONCLUSIONS

The high concentrations of serum iron and ferritin in early pregnancy have a certain correlation with the incidence of GDM, and the early detection of serum iron and ferritin levels can improve the detection rate of GDM in pregnant metaphase.

The identification and treatment of women with hyperglycaemia in pregnancy: an analysis of individual participant data, systematic reviews, meta-analyses and an economic evaluation

BACKGROUND

Gestational diabetes mellitus (GDM) is associated with a higher risk of important adverse outcomes. Practice varies and the best strategy for identifying and treating GDM is unclear.

AIM

To estimate the clinical effectiveness and cost-effectiveness of strategies for identifying and treating women with GDM.

METHODS

We analysed individual participant data (IPD) from birth cohorts and conducted systematic reviews to estimate the association of maternal glucose levels with adverse perinatal outcomes; GDM prevalence; maternal characteristics/risk factors for GDM; and the effectiveness and costs of treatments. The cost-effectiveness of various strategies was estimated using a decision tree model, along with a value of information analysis to assess where future research might be worthwhile. Detailed systematic searches of MEDLINE^® and MEDLINE In-Process & Other Non-Indexed Citations^®, EMBASE, Cumulative Index to Nursing and Allied Health Literature Plus, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Health Technology Assessment database, NHS Economic Evaluation Database, Maternity and Infant Care database and the Cochrane Methodology Register were undertaken from inception up to October 2014.

RESULTS

We identified 58 studies examining maternal glucose levels and outcome associations. Analyses using IPD alone and the systematic review demonstrated continuous linear associations of fasting and post-load glucose levels with adverse perinatal outcomes, with no clear threshold below which there is no increased risk. Using IPD, we estimated glucose thresholds to identify infants at high risk of being born large for gestational age or with high adiposity; for South Asian (SA) women these thresholds were fasting and post-load glucose levels of 5.2 mmol/l and 7.2 mmol/l, respectively and for white British (WB) women they were 5.4 and 7.5 mmol/l, respectively. Prevalence using IPD and published data varied from 1.2% to 24.2% (depending on criteria and population) and was consistently two to three times higher in SA women than in WB women. Lowering thresholds to identify GDM, particularly in women of SA origin, identifies more women at risk, but increases costs. Maternal characteristics did not accurately identify women with GDM; there was limited evidence that in some populations risk factors may be useful for identifying low-risk women. Dietary modification additional to routine care reduced the risk of most adverse perinatal outcomes. Metformin (Glucophage,^® Teva UK Ltd, Eastbourne, UK) and insulin were more effective than glibenclamide (Aurobindo Pharma - Milpharm Ltd, South Ruislip, Middlesex, UK). For all strategies to identify and treat GDM, the costs exceeded the health benefits. A policy of no screening/testing or treatment offered the maximum expected net monetary benefit (NMB) of £1184 at a cost-effectiveness threshold of £20,000 per quality-adjusted life-year (QALY). The NMB for the three best-performing strategies in each category (screen only, then treat; screen, test, then treat; and test all, then treat) ranged between -£1197 and -£1210. Further research to reduce uncertainty around potential longer-term benefits for the mothers and offspring, find ways of improving the accuracy of identifying women with GDM, and reduce costs of identification and treatment would be worthwhile.

LIMITATIONS

We did not have access to IPD from populations in the UK outside of England. Few observational studies reported longer-term associations, and treatment trials have generally reported only perinatal outcomes.

CONCLUSIONS

Using the national standard cost-effectiveness threshold of £20,000 per QALY it is not cost-effective to routinely identify pregnant women for treatment of hyperglycaemia. Further research to provide evidence on longer-term outcomes, and more cost-effective ways to detect and treat GDM, would be valuable.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013004608.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Gestational diabetes mellitus in an Iranian pregnant population using IADPSG criteria: Incidence, contributing factors and outcomes

AIMS

Different approaches for screening and diagnosis of gestational diabetes mellitus(GDM) have great impact on all process of management of gestational diabetes and its future complications. The aims of this study were to evaluate rate, risk factors and outcomes of GDM based on International Association of Diabetes and Pregnancy Study Groups diagnostic criteria.

MATERIALS

In a prospective study pregnant women attended 5 clinics in Ahvaz, screened for gestational diabetes mellitus using IADPSG criteria and followed up delivery from August 2014 to February 2015. At the first prenatal visit women underwent the fasting blood sugar test. A 75-g oral glucose tolerance test (OGTT) was performed for 750 mothers between 24 and 32 weeks of gestation. Logistic regression test for calculating the odds ratios and 95% confidence intervals was used.

RESULTS

The mean age of participants was 28.43±5.52years. The overall rate of GDM in our study was 29.9% (224/750). Incidence of gestational diabetes was associated with age group≥35years [OR=1.92(95% CI, 1.19-3.09)], family history of diabetes [OR=2.47(95% CI, 1.33-4.59)], previous GDM [OR=3.12(1.35-7.19)], BMI≥25 [OR=1, 71(1.10-2.67)] Using logistic regression. The most common maternal complication in studied women was cesarean section followed by hypertension and preeclampsia.

CONCLUSION

About one third of studied women diagnosed as GDM according to the IADPSG criteria. Risk factors of GDM were maternal age, family history of diabetes, Previous GDM, overweight and obesity before pregnancy, the same reported factors with 2 steps approach. Higher rate of GDM using this criterion may increase concern about healthcare costs and workloads.

50 Grams Oral Glucose Challenge Test: Is It an Effective Screening Test for Gestational Diabetes Mellitus?

AIM

To find out whether 50 g oral glucose challenge test (OGCT) is an effective screening test for all pregnant women between 24 and 28 weeks gestation.

METHOD

A 50 g OGCT test was administered to 307 unselected women at 24-28 weeks of gestation. When venous plasma glucose (VPG) concentration after 1 h was >7.8 mmol/l, OGCT was positive. Women with a positive OGCT underwent 2 h 75 grams oral glucose tolerance test (OGTT) as a confirmatory diagnosis of GDM. When fasting and 2 h post 75 g OGTT values were >5.5 mmol/I and >8 mmol/l, respectively, women were considered diabetic.

RESULTS

We screened 307 women for GDM by OGCT. Total number of women with positive OGCT was 83 (27.03 %). In the low-risk group, total number of women with GDM was 9/168 (5.35 %) while the total number of women with GDM in the high-risk group was 14/139 (10.07 %). There was no significant difference with respect to the total number of women with GDM in the groups.

CONCLUSIONS

A 50 g OGCT seems to be an effective screening test for both groups. More cases of GDM can be discovered when universal rather than risk-related screening is applied.

Prevalence of gestational diabetes mellitus and associated risk factors in Turkish women: the Trabzon GDM Study

INTRODUCTION

The aim of this study was to investigate the prevalence of gestational diabetes mellitus (GDM) in Turkish pregnant women in the Trabzon Region and further to identify population-specific risk factors for GDM.

MATERIAL AND METHODS

In this prospective cross-sectional survey, universal screening for GDM was performed in 815 pregnant women. Screening was done with a 50-g oral glucose challenge test (GCT) with a 140 mg/dl cut-off point, then a diagnostic 100 g oral glucose tolerance test (OGTT) was performed according to Carpenter and Coustan (CC) criteria.

RESULTS

The GCT was positive in 182 (22.3%) cases. The OGTT was performed on the 182 screen-positive pregnant women. Thirty-five were diagnosed with GDM on the basis of their results for a prevalence of 4.3% (35/815). Of the pregnancies with negative GCT but having high risk factors for GDM (n = 31), 4 were diagnosed with GDM (0.5%). Prevalence of GDM was found to be 4.8% (n = 39) for all pregnant women. Gestational diabetes mellitus was positively associated with advanced maternal age (p < 0.001), prepregnancy body mass index (p < 0.001), cessation of cigarette smoking (p < 0.001), excessive weight gain during pregnancy (p = 0.003), previous history of GDM (p < 0.001), history of selected medical conditions (p = 0.018), family history of diabetes (FHD) (p < 0.001), and existence of at least one high risk factor for GDM (p < 0.001). In multiple logistic regression analysis, independent predictors for GDM were maternal age, cessation of cigarette smoking, increasing prepregnancy body mass index, weight gain of more than 8 kg during pregnancy, GDM history in previous pregnancies and a history of diabetes in first-degree relatives of pregnant women.

CONCLUSIONS

The prevalence of GDM in Trabzon province was found as moderate. Commonly recognized risk factors including older age, prepregnancy obesity, FHD and past history of GDM, are valid for our urban Turkish population. Also, excessive weight gain in pregnancy and cigarette cessation were observed to be nontradional risk factors of GDM. It was concluded that all pregnant women should be screened for GDM if prevalence was not low.

Prevalence of gestational diabetes mellitus and its risk factors in Chinese pregnant women: a prospective population-based study in Tianjin, China

Objective

We compared the increases in the prevalence of gestational diabetes mellitus (GDM) based on the 1999 World Health Organization (WHO) criteria and its risk factors in Tianjin, China, over a 12-year period. We also examined the changes in the prevalence using the criteria of International Association of Diabetes and Pregnancy Study Group (IADPSG).

Methods

In 2010-2012, 18589 women who registered within 12 weeks of gestation underwent a glucose challenge test (GCT) at 24-28 gestational weeks. Amongst them, 2953 women with 1-hour plasma glucose ≥7.8 mmol/L underwent a 75-gram 2-hour oral glucose tolerance test (OGTT) and 781 women had a positive GCT but absented from the standard OGTT. An adjusted prevalence of GDM was calculated for the whole cohort of women by including an estimate of the proportion of women with positive GCTs who did not have OGTTs but would have been expected to have GDM. Logistic regression was used to obtain odds ratios and 95% confidence intervals using the IADPSG criteria. The prevalence of GDM risk factors was compared to the 1999 survey.

Results

The adjusted prevalence of GDM by the 1999 WHO criteria was 8.1%, a 3.5-fold increase as in 1999. Using the IADPSG criteria increased the adjusted prevalence further to 9.3%. Advanced age, higher pre-pregnancy body mass index, Han-nationality, higher systolic blood pressure (BP), a family history of diabetes, weight gain during pregnancy and habitual smoking were risk factors for GDM. Compared to the 1999 survey, the prevalence of overweight plus obesity had increased by 1.8 folds, age≥30 years by 2.3 folds, systolic BP by 2.3 mmHg over the 12-year period.

Conclusions

Increasing prevalence of overweight/obesity and older age at pregnancy were accompanied by increasing prevalence of GDM, further increased by change in diagnostic criteria.

Screening and subsequent management for gestational diabetes for improving maternal and infant health

BACKGROUND

Gestational diabetes mellitus (GDM) is a form of diabetes that occurs in pregnancy. Although GDM usually resolves following birth, it is associated with significant morbidities for mother and baby both perinatally and in the long term. There is strong evidence to support treatment for GDM. However, there is little consensus on whether or not screening for GDM will improve maternal and infant health and if so, the most appropriate protocol to follow.

OBJECTIVES

To assess the effects of different methods of screening for GDM and maternal and infant outcomes.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (1 December 2013).

SELECTION CRITERIA

Randomised and quasi-randomised trials evaluating the effects of different methods of screening for GDM.

DATA COLLECTION AND ANALYSIS

Two review authors independently conducted data extraction and quality assessment. We resolved disagreements through discussion or through a third author.

MAIN RESULTS

We included four trials involving 3972 women in the review. One quasi-randomised trial compared risk factor screening with universal or routine screening by 50 g oral glucose challenge testing. Women in the universal screening group were more likely to be diagnosed with GDM (one trial, 3152 women, risk ratio (RR) 0.44, 95% confidence interval (CI) 0.26 to 0.75). This trial did not report on the other primary outcomes of the review (positive screen for GDM, mode of birth, large-for-gestational age, or macrosomia). Considering secondary outcomes, infants of mothers in the risk factor screening group were born marginally earlier than infants of mothers in the routine screening group (one trial, 3152 women, mean difference (MD) -0.15 weeks, 95% CI -0.27 to -0.03).The remaining three trials evaluated different methods of administering a 50 g glucose load. Two small trials compared glucose monomer with glucose polymer testing, with one of these trials including a candy bar group. One trial compared a glucose solution with food. No differences in diagnosis of GDM were found between each comparison. However, in one trial significantly more women in the glucose monomer group screened positive for GDM than women in the candy bar group (80 women, RR 3.49, 95% CI 1.05 to 11.57). The three trials did not report on the primary review outcomes of mode of birth, large-for-gestational age or macrosomia. Overall, women drinking the glucose monomer experienced fewer side effects from testing than women drinking the glucose polymer (two trials, 151 women, RR 2.80, 95% CI 1.10 to 7.13). However, we observed substantial heterogeneity between the trials for this result (I² = 61%).

AUTHORS' CONCLUSIONS

There was insufficient evidence to determine if screening for gestational diabetes, or what types of screening, can improve maternal and infant health outcomes.

Prevalence of gestational diabetes mellitus and its outcome in western Rajasthan

BACKGROUND

Gestational diabetes mellitus (GDM) is a metabolic disorder defined as glucose intolerance with the onset or first recognition during pregnancy. Women with GDM are at increased risk for adverse obstetric and perinatal outcome. Hence, it is imperative that an early detection and management of the disease is done to ensure better maternal and fetal outcomes.

AIMS

This study was done to evaluate the prevalence of gestational diabetes using diabetes in pregnancy Study Group India (DIPSI) criteria and further assess its feto-maternal outcome in western Rajasthan.

MATERIALS AND METHODS

This study was carried out in 500 patients between 24 and 28 weeks of gestation, attending the antenatal outdoor. These patients were given 75 g oral glucose irrespective of the meals and their plasma glucose was estimated at 2 h. Patients with plasma glucose values ΃140 mg/dl were labeled as GDM and the rest as the control or the non-GDM group. All GDM patients were followed up and treated with diet and/or insulin therapy till delivery to know maternal and fetal outcomes.

RESULTS

The prevalence of GDM in this study was 6.6%. Maternal and fetal complications in the GDM group were much higher than in the non-GDM group. Hypertension, vaginal candidiasis, and abruptio placentae were the common maternal complications, while macrosomia and stillbirths occurred in the fetuses.

CONCLUSION

GDM as a disease entity adversely affects maternal and fetal outcomes. This also builds a strong case for following DIPSI guidelines in diagnosis and management of GDM.

Gestational diabetes mellitus: including serum pregnancy-associated plasma protein-A testing in the clinical management of primiparous women? A case-control study

AIMS

To assess pregnancy-associated plasma protein A (PAPP-A) correlation with GDM and its usefulness in predicting GDM in primiparous women.

METHODS

First trimester data related to 307 pregnant women affected by GDM and 366 control pregnant women were retrieved from a computer data base and integrated with ad hoc data. Clinical data were recorded at delivery. A logistic model was used to analyze the association between first trimester data and subsequent clinical outcomes. We derived a risk score using both classical risk factors for GDM and PAPP-A.

RESULTS

Diabetic and control women were significantly different in terms of age (p<0.001), BMI (p<0.001), weight (p<0.001), family history of diabetes (p<0.001), PAPP-A concentration and PAPP-A corrected multiple of the median (MoM) (p<0.001). The ROC-AUC of the clinical risk score was 0.60 (95%CI 0.56-0.64), the adjusted score including PAPP-A MoM was 0.70 (95%CI 0.66-0.74).

CONCLUSIONS

Low PAPP-A was strongly associated with GDM and lower values were found in diabetic women needing insulin therapy. Adding PAPP-A to first trimester screening could improve the prediction of women at high risk who will develop GDM. Further studies are needed to validate the applicability of our findings in different populations and settings.

myo-Inositol supplementation and onset of gestational diabetes mellitus in pregnant women with a family history of type 2 diabetes: a prospective, randomized, placebo-controlled study

OBJECTIVE

To check the hypothesis that myo-inositol supplementation may reduce gestational diabetes mellitus (GDM) onset in pregnant women with a family history of type 2 diabetes.

RESEARCH DESIGN AND METHODS

A 2-year, prospective, randomized, open-label, placebo-controlled study was carried out in pregnant outpatients with a parent with type 2 diabetes who were treated from the end of the first trimester with 2 g myo-inositol plus 200 µg folic acid twice a day (n = 110) and in the placebo group (n = 110), who were only treated with 200 µg folic acid twice a day. The main outcome measure was the incidence of GDM in both groups. Secondary outcome measures were as follows: the incidence of fetal macrosomia (>4,000 g), gestational hypertension, preterm delivery, caesarean section, shoulder dystocia, neonatal hypoglycemia, and neonatal distress respiratory syndrome. GDM diagnosis was performed according to the International Association of the Diabetes and Pregnancy Study Groups (IADPSG) recommendations.

RESULTS

Incidence of GDM was significantly reduced in the myo-inositol group compared with the placebo group: 6 vs. 15.3%, respectively (P = 0.04). In the myo-inositol group, a reduction of GDM risk occurrence was highlighted (odds ratio 0.35). A statistically significant reduction of fetal macrosomia in the myo-inositol group was also highlighted together with a significant reduction in mean fetal weight at delivery. In the other secondary outcome measures, there were no differences between groups.

CONCLUSIONS

myo-Inositol supplementation in pregnant women with a family history of type 2 diabetes may reduce GDM incidence and the delivery of macrosomia fetuses.

Periodontitis and gestational diabetes mellitus in non-smoking females

BACKGROUND

Chronic inflammation has been implicated in the pathogenesis of gestational diabetes mellitus (GDM). Periodontal disease is associated with increased levels of inflammatory mediators and may be a risk factor for GDM. The authors aimed to examine the association between periodontitis and GDM among non-smoking pregnant females.

METHODS

This case-control study included 50 females who were diagnosed with GDM and 50 age- and hospital-matched females without diabetes in Khon Kaen, Thailand. Full-mouth periodontal examinations were performed during pregnancy by two calibrated dentists who were unaware of the case-control status. Periodontitis was defined as ≥1 site with probing depth (PD) ≥5 mm and clinical attachment level (CAL) ≥2 mm at the same site. Serum samples were collected to measure C-reactive protein (CRP), tumor necrosis factor-α, and interleukin-6 levels. Analyses were performed using conditional logistic regression.

RESULTS

Fifty percent of the case females had periodontitis compared to 26% of the controls. Females with GDM had significantly higher mean PD and CAL, more sites with bleeding on probing, and increased levels of CRP compared to the controls. Periodontitis was significantly associated with GDM (odds ratio = 3.00, 95% confidence interval = 1.19 to 7.56). The association remained significant with additional adjustment for family history of diabetes, prepregnancy body mass index, and weight gain during pregnancy.

CONCLUSIONS

The results suggest that periodontitis is associated with GDM. Therefore, clinicians should assess periodontal conditions of pregnant females.

Screening in high-risk group of gestational diabetes mellitus with its maternal and fetal outcomes

BACKGROUND

Gestational diabetes mellitus (GDM) is a metabolic disorder defined as glucose intolerance with the onset or first recognition during pregnancy. Women with GDM are at increased risk for adverse obstetric and perinatal outcome. The complications associated with GDM can be prevented by early recognition, intense monitoring and proper treatment.

AIMS

The present study was done to screen the high-risk pregnancy group for GDM, to find the incidence of abnormal results on screening and to correlate the abnormal results with the maternal and fetal outcomes. The study was done in a tertiary care hospital and teaching institute. It was a prospective cohort study.

MATERIALS AND METHODS

Selective screening for GDM was done in 150 pregnant women with high-risk factors. Screening was done with 50 g glucose challenge test (GCT) after 18 weeks, and if GCT was negative then the test was repeated after 28 weeks of pregnancy. The patients who were having an abnormal GCT were subjected to 100 g oral glucose tolerance test (OGTT). All GDM patients were followed up and treated with diet and/or insulin therapy till delivery to know maternal and fetal outcomes. The period of study was from April 2008 to March 2009.

RESULTS

7.3% of study population was OGCT positive. 6% of the study population was OGTT positive. Age >25 years, obesity, family history of DM, and past history of GDM were the risk factors significantly associated with GDM. One newborn had hypoglycemia and one had hyperbilirubinemia. The fetal and maternal outcome in GDM patients was good in our study due to early diagnosis and intervention.

CONCLUSION

Women with GDM are at an increased risk for adverse obstetric and perinatal outcome. The increased morbidity in GDM is preventable by meticulous antenatal care.

Gestational diabetes: development of an early risk prediction tool to facilitate opportunities for prevention

BACKGROUND AND AIM

In the setting of advancing maternal age, escalating obesity and increasing Gestational Diabetes Mellitus (GDM) rates, we aimed to develop a novel risk prediction tool to identify high-risk women in early pregnancy, specifically to facilitate targeted antenatal prevention of GDM.

METHODS

In this retrospective, observational study, first-trimester data collected routinely by midwifery staff in 4276 women attending a large tertiary hospital in 2007/2008 was analysed to examine predictive factors for GDM. GDM was diagnosed with a 28-week oral glucose tolerance test. The data set included a derivation group (n=2880, from 2007 deliveries) and a validation group (n = 1396, from 2008). Multivariate analysis generated a scoring system.

RESULTS

GDM was significantly correlated with a number of factors: past history of GDM, increasing maternal age and body mass index, Asian descent and family history of diabetes. Validation group clinical scores achieved a sensitivity of 61.3% and specificity of 71.4% for differentiating women according to their risk of developing GDM.

CONCLUSIONS

Risk factors for GDM are easily identified at the first-trimester midwifery hospital booking visit. A risk prediction tool, derived from risk factors in early pregnancy, identifies women at high risk of GDM. This represents a novel approach to facilitate targeted early intervention with the potential to prevent development of, or ameliorate, GDM.

Definition, epidemiology, risk factors

Gestational diabetes mellitus is defined as glucose intolerance that begins or is first recognized during pregnancy. Its prevalence, generally situated between 2-6%, may reach 10-20% in high-risk populations, with an increasing trend across most racial/ethnic groups studied. Among traditional risk factors, previous gestational diabetes, advanced maternal age and obesity have the highest impact on gestational diabetes risk. Racial/ethnic origin and family history of type 2 diabetes have a significant but moderate impact (except for type 2 diabetes in siblings). Several non traditional factors have been recently characterized, either physiological (low birthweight and short maternal height) or pathological (polycystic ovaries). The multiplicity of risk factors and their interactions results in a low reliability of risk prediction on an individual basis.

Gestational diabetes guidelines in a HAPO world

The impact of gestational diabetes on maternal and fetal health has been increasingly recognized. However, universal consensus on the diagnostic methods and thresholds has long been lacking. Published guidelines from major societies differ considerably from one another, ranging in recommendations from aggressive screening to no routine screening at all. As a result, real-world practice is equally varied. The recently published Hyperglycemia and Adverse Pregnancy Outcomes (HAPO) study, and two randomized controlled trials evaluating treatment of mild maternal hyperglycemia, have served to confirm the findings of smaller, nonrandomized studies solidifying the link between maternal hyperglycemia and adverse perinatal outcomes. In response to these studies, the International Association of Diabetes and Pregnancy Study Groups (IADPSG) has formulated new guidelines for screening and diagnosis of diabetes in pregnancy. Key components of the IADPSG guidelines include the recommendation to screen high-risk women at the first encounter for pre-gestational diabetes, to screen universally at 24-28 weeks' gestation, and to screen with use of the 75-g oral glucose tolerance test interpreting abnormal fasting, 1-h, and 2-h plasma glucose concentrations as individually sufficient for the diagnosis of gestational diabetes. Furthermore, to translate the continuous association between maternal glucose and adverse outcomes demonstrated in the HAPO cohort, they recommend thresholds for positive screening tests at which the odds of elevated birth weight, cord C-peptide, and fetal percent body fat are 1.75 relative to odds of those outcomes at mean glucose values. Opponents to the IADPSG recommendations will likely be those who favor risk-based screening in addition to those who endorse the 50-g glucose challenge test followed by the 100-g oral glucose tolerance test as a more cost-effective, familiar, and possibly, well-validated screening tool. Others may argue that the diagnostic thresholds chosen by the IADPSG are arbitrary and will continue to miss many cases of abnormal glucose metabolism and therefore leave open the possibility of adverse perinatal outcomes due to untreated gestational diabetes. Finally, the potential economic impact of the IADPSG guidelines are unknown, and with minimal long-term data yet available on the offspring of the HAPO cohort, a true cost-effectiveness analysis will be difficult to perform accurately. Given these potential points of contention, the responses of professional and international groups to the IADPSG guidelines are difficult to gauge. Regardless, these guidelines serve to advance the discussion on appropriate screening and diagnosis of diabetes in pregnancy.

Screening and subsequent management for gestational diabetes for improving maternal and infant health

BACKGROUND

Gestational diabetes mellitus (GDM) is a form of diabetes that occurs in pregnancy. Although GDM usually resolves following birth, it is associated with significant morbidities for mother and baby both perinatally and in the long term. There is strong evidence to support treatment for GDM. However, there is little consensus on whether or not screening for GDM will improve maternal and infant health and if so, the most appropriate protocol to follow.

OBJECTIVES

To assess the effects of different methods of screening for gestational diabetes mellitus and maternal and infant outcomes.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (April 2010).

SELECTION CRITERIA

Randomised and quasi-randomised trials evaluating the effects of different methods of screening for gestational diabetes mellitus.

DATA COLLECTION AND ANALYSIS

Two review authors independently conducted data extraction and quality assessment. We resolved disagreements through discussion or through a third author.

MAIN RESULTS

We included four trials involving 3972 women were included in the review. One quasi-randomised trial compared risk factor screening with universal or routine screening by 50 g oral glucose challenge testing. Women in the universal screening group were more likely to be diagnosed with GDM (one trial, 3152 women, risk ratio (RR) 0.44 95% confidence interval (CI) 0.26 to 0.75). Infants of mothers in the risk factor screening group were born marginally earlier than infants of mothers in the routine screening group (one trial, 3152 women, mean difference -0.15 weeks, 95% CI -0.27 to -0.53).The remaining three trials evaluated different methods of administering a 50 g glucose load. Two small trials compared glucose monomer with glucose polymer testing, with one of these trials including a candy bar group. One trial compared a glucose solution with food. No differences in diagnosis of GDM were found between each comparison. Overall, women drinking the glucose monomer experienced fewer side effects from testing than women drinking the glucose polymer (two trials, 151 women, RR 2.80, 95% CI 1.10 to 7.13). However, we observed high heterogeneity between the trials for this result (I(2) = 61%).

AUTHORS' CONCLUSIONS

There was insufficient evidence to determine if screening for gestational diabetes, or what types of screening, can improve maternal and infant health outcomes.

Prepregnancy BMI and the risk of gestational diabetes: a systematic review of the literature with meta-analysis

The objective of this study is to assess and quantify the risk for gestational diabetes mellitus (GDM) according to prepregnancy maternal body mass index (BMI). The design is a systematic review of observational studies published in the last 30 years. Four electronic databases were searched for publications (1977-2007). BMI was elected as the only measure of obesity, and all diagnostic criteria for GDM were accepted. Studies with selective screening for GDM were excluded. There were no language restrictions. The methodological quality of primary studies was assessed. Some 1745 citations were screened, and 70 studies (two unpublished) involving 671 945 women were included (59 cohorts and 11 case-controls). Most studies were of high or medium quality. Compared with women with a normal BMI, the unadjusted pooled odds ratio (OR) of an underweight woman developing GDM was 0.75 (95% confidence interval [CI] 0.69 to 0.82). The OR for overweight, moderately obese and morbidly obese women were 1.97 (95% CI 1.77 to 2.19), 3.01 (95% CI 2.34 to 3.87) and 5.55 (95% CI 4.27 to 7.21) respectively. For every 1 kg m(-2) increase in BMI, the prevalence of GDM increased by 0.92% (95% CI 0.73 to 1.10). The risk of GDM is positively associated with prepregnancy BMI. This information is important when counselling women planning a pregnancy.

Cigarette smoking and risk of gestational diabetes: a systematic review of observational studies

BACKGROUND

Gestational diabetes is a prevalent disease associated with adverse outcomes of pregnancy. Smoking as been associated with glucose intolerance during pregnancy in some but not all studies. Therefore, we aimed to systematically review all epidemiological evidence to examine the association between cigarette smoking during pregnancy and risk of developing gestational diabetes mellitus.

METHODS

We conducted a systematic review of articles published up to 2007, using PubMed, Embase, LILACS e CINAHL to identify the articles. Because this review focuses on studies of smoking during pregnancy, we excluded studies evaluating smoking outside pregnancy. Two investigators independently abstracted information on participant's characteristics, assessment of exposure and outcome, and estimates for the association under study. We evaluated the studies for publication bias and performed heterogeneity analyses. We also assessed the effect of each study individually through sensitivity analysis.

RESULTS

We found and critically reviewed 32 studies, of which 12 met the criteria for inclusion in the review. Most of the studies provided only unadjusted measurements. Combining the results of the individual studies, we obtained a crude odds ratio of 1.03 (99% CI 0.85-1.25). Only 4 studies presented adjusted measurements of association, and no association was found when these alone were analyzed (OR 0.95; 99% CI 0.85-1.07). Subgroup analysis could not be done due to small sample size.

CONCLUSION

The number of studies is small, with major heterogeneity in research design and findings. Taken together, current data do not support an association between cigarette smoking during pregnancy and the risk of gestational diabetes.

The increasing prevalence of diabetes in pregnancy

The authors review studies published in the past 10 years that examine the prevalence and trends in the prevalence of gestational diabetes mellitus (GDM). The prevalence of GDM in a population is reflective of the prevalence of type 2 diabetes within that population. In low-risk populations, such as those found in Sweden, the prevalence in population-based studies is lower than 2% even when universal testing is offered, whereas studies in high-risk populations, such as the Native American Cree, Northern Californian Hispanics, and Northern Californian Asians, reported prevalence rates ranging from 4.9% to 12.8%. Prevalence rates for GDM obtained from hospital-based studies similarly reflect the risk of type 2 diabetes in a population with a single hospital-based study in Australia reporting prevalences ranging from 3.0% in Anglo-Celtic women to 17.0% in Indian women. Finally, of the eight studies published that report on trends in the prevalence of GDM, six report an increase in the prevalence of GDM across most racial/ethnic groups studied. In summary, diabetes during pregnancy is a common and increasing complication of pregnancy.

The increasing prevalence of diabetes in pregnancy

The authors review studies published in the past 10 years that examine the prevalence and trends in the prevalence of gestational diabetes mellitus (GDM). The prevalence of GDM in a population is reflective of the prevalence of type 2 diabetes within that population. In low-risk populations, such as those found in Sweden, the prevalence in population-based studies is lower than 2% even when universal testing is offered, whereas studies in high-risk populations, such as the Native American Cree, Northern Californian Hispanics, and Northern Californian Asians, reported prevalence rates ranging from 4.9% to 12.8%. Prevalence rates for GDM obtained from hospital-based studies similarly reflect the risk of type 2 diabetes in a population with a single hospital-based study in Australia reporting prevalences ranging from 3.0% in Anglo-Celtic women to 17.0% in Indian women. Finally, of the eight studies published that report on trends in the prevalence of GDM, six report an increase in the prevalence of GDM across most racial/ethnic groups studied. In summary, diabetes during pregnancy is a common and increasing complication of pregnancy.

Gestational Diabetes: A Review of the Current Literature and Guidelines

Despite large numbers of original research studies spanning 4 decades there is still no consensus on the subject of gestational diabetes. Should all pregnant women be screened or only those with risk factors? Or is it safe not to screen at all? Which screening test and which diagnostic test are the most reliable? Which cutoff values should we use? What are the risks involved for mother and baby and can treatment improve outcome? What is the connection between gestational diabetes and diabetes mellitus type II? Are there disadvantages to screening? A review of relevant articles shows that definitive answers to these questions are not yet available. There is no gold standard screening test and no threshold glucose value above which complications are markedly increased. On the contrary, there appears to be a continuum of slowly increasing risks with rising blood glucose values, where it seems difficult to draw a clear line between pathology and physiology. Moreover, treatment has thus far not been shown to significantly improve outcome. There seems to be an indistinct area between the diagnosis of gestational diabetes and diabetes mellitus type II, where women with risk factors for one are also predisposed to develop the other, thereby confusing the diagnosis. Finally, the disadvantages to diagnosing and treating women without a clearly proven benefit seem to be significant. Therefore it seems defensible to suspend all screening and treatment for gestational diabetes, or at least significantly raise the threshold for making a positive diagnosis and initiating treatment, until further research has proven a clear benefit.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader should be able to summarize that there is still no worldwide consensus on the diagnosis, management, and adverse effects of Gestational Diabetes Mellitus (GDM); explain that all methods of screening vary in sensitivity and depend on very strict preparations for screening; state that there is no agreement on ideal levels of blood glucose to prevent untoward effects; and recall that there are two very large prospective studies that clarify the dark waters and that we should await their results.

Adipose tissue from pregnant women with and without gestational diabetes mellitus: insulin-sensitive but resistant to hyperosomolarity

OBJECTIVE

We sought to determine the contribution of adipose tissue to the insulin resistance of pregnancy. We also investigated whether hyperosmolar stress (induced by sorbitol) stimulates glucose uptake in human adipose tissue and, if so, whether this effect is altered in pregnancy and gestational diabetes mellitus.

STUDY DESIGN

Subcutaneous and omental adipose tissue biopsy specimens were obtained at elective abdominal surgery or cesarean delivery from 16 normal glucose-tolerant pregnant women, 13 pregnant women with gestational diabetes mellitus, and 19 body mass index-matched nonpregnant control subjects. Basal, insulin (100 nmol/L)-, and sorbitol (250 mmol/L)-stimulated glucose uptake levels were measured.

RESULTS

Basal and insulin-stimulated glucose uptake into adipose tissue was not impaired in pregnancy or gestational diabetes mellitus compared with control subjects. Hyperosmolarity stimulated glucose uptake in human adipose tissue from the subcutaneous, but not omental depot, and not in adipose tissue from pregnant subjects.

CONCLUSION

There is no significant difference in insulin sensitivity in adipose tissue from pregnant or nonpregnant women; hyperosmolarity stimulates glucose uptake in subcutaneous adipose tissue from nonpregnant women, and adipose tissue from pregnant women is sorbitol resistant. These findings suggest the phosphotidylinositol 3-kinase-independent pathway may have pathophysiologic relevance to glucose uptake in human adipose tissue and may be impaired in pregnancy.

Repeated random blood glucose measurements as universal screening test for gestational diabetes mellitus

BACKGROUND

To determine the value of repeated random blood glucose (R-B-glucose) measurements alone or in combination with traditional risk factors [family history of diabetes, obesity, prior large-for-gestational-age (LGA) infant or prior gestational diabetes mellitus (GDM)] to predict the outcome of the oral glucose tolerance test (OGTT).

METHODS

A prospective population-based study was undertaken in a Swedish county. All pregnant nondiabetic women (n = 4918) visiting the maternal health care clinics over a 2-year period were offered a 75-g OGTT in gestational weeks 28-32. Traditional risk factors and values of repeated R-B-glucose measurements were registered, as well as the results of the OGTT, in terms of fasting B-glucose and 2-h B-glucose.

RESULTS

A total of 3616 women (73.5%) had an OGTT. Of these, 1.7% had GDM, 1.3% impaired glucose tolerance (IGT) and 0.4% diabetes mellitus (DM). An R-B-glucose cut-off level > or =8.0 mmol/L as the only indicator for an OGTT was optimal for detecting GDM with regard to sensitivity (47.5%) and specificity (97.0%). It has the same sensitivity for detecting GDM as using traditional risk factors, but reduces the need to carry out the OGTT from 15.8% to 3.8% of the population. Combined with prior LGA infant or prior GDM as indications for the OGTT in the present study, all women with DM and 44.7% of those with IGT will be identified. Only 7.3% of the population will have to take the OGTT.

CONCLUSION

A random B-glucose level > or = 8.0 mmol/L prior LGA infant or prior GDM as an indicator for taking the OGTT is a simple and effective first step in a two-step screening model for GDM.

Population health significance of gestational diabetes

OBJECTIVE

Women who have had gestational diabetes mellitus (GDM) have a high risk of subsequently developing diabetes. However, the contribution of GDM toward the total population of people with diabetes, or its population health impact, has not been examined. Therefore, the aim of this study is to determine the population health significance of GDM by estimating the proportion of cases of diabetes in women that would have been preceded by a pregnancy complicated by GDM.

RESEARCH DESIGN AND METHODS

A MEDLINE search was conducted to identify controlled follow-up studies of women with GDM. Meta-analysis of these studies, using the Mantel-Haenszel method for pooling relative risks (RRs), provided an overall RR for the development of diabetes in women with GDM versus control women who had been pregnant without GDM. Recent large studies examining the prevalence of GDM were also reviewed. This enabled the calculation of the population-attributable risk (PAR) for these populations. In this case, the PAR represents the proportion of cases of diabetes among parous women that were associated with previous GDM.

RESULTS

From six controlled follow-up studies, the overall RR for developing diabetes after GDM was calculated to be 6.0 (95% CI 4.1-8.8). Applying this to the studies of GDM prevalence, the PAR for GDM ranged from 0.10 to 0.31 (i.e., 10-31% of parous women with diabetes would have experienced a GDM pregnancy earlier).

CONCLUSIONS

In some populations, women who have had GDM comprise a substantial proportion of subjects who ultimately develop diabetes. Effective measures to prevent women with GDM from progressing to frank diabetes could therefore have a significant population health impact.

Occurrence of gestational diabetes mellitus and the value of different screening indicators for the oral glucose tolerance test

BACKGROUND

The objective of the present study was to determine prevalence of gestational diabetes mellitus (GDM) in terms of impaired glucose tolerance (IGT) and diabetes mellitus (DM), and the value of traditional anamnestic risk factors for predicting outcome of the oral glucose tolerance test (OGTT).

METHODS

A prospective population-based study in a defined geographic area in Sweden. All pregnant nondiabetic women (n = 4918) attending maternal health care from July 1994 to June 1996 were offered a 75g OGTT in gestational weeks 28-32. Traditional anamnestic risk factors, as well as results of the OGTT in terms of fasting-B-glucose and 2h-B-glucose, were registered.

RESULTS

3616 (73.5%) women agreed to perform the OGTT. Sixty-one (1.7%) of those had GDM [47 (1.3%) had impaired glucose tolerance and 14 (0.4%) had diabetes mellitus]. 15.8% fulfilled traditional risk factor criteria. Traditional anamnestic risk factors as an indicator to perform an OGTT identified 29/61 GDM women and 9/14 women with DM. Among primiparas, 4/21 with gestational diabetes mellitus were detected.

CONCLUSION

Using traditional risk factors as an indicator to perform an OGTT gives a low sensitivity to detect GDM and even DM especially among primiparas.