Glycohemoglobin A1c: A promising screening tool in gestational diabetes mellitus

Study of Serum Adiponectin and Interleukin-1β Levels in Women with Gestational Diabetes

Introduction

Pregnancy is associated with alterations in the regulation of glucose metabolism caused by actions of various placental hormones and substances that antagonise the action of insulin leading to a state of relative insulin resistance as pregnancy progresses. Gestational diabetes mellitus (GDM) is defined as any degree of glucose intolerance with onset or first recognition during pregnancy. Adiponectin is known to be synthesised by adipocytes as well as by the placenta during pregnancy. It has an insulin-sensitising and anti-atherosclerotic actions. Interleukin-1β (IL-1β) is a member of interleukin-1 cytokine family and is known to involve in immune-mediated disease and regulation of inflammation. Accumulating evidence indicates that diseases related to metabolic syndrome are characterised by abnormal cytokine production, including IL-1β.

Objectives

To evaluate serum adiponectin and IL-1β levels in women with GDM and correlate their levels with blood glucose level.

Materials and Methods

A hospital-based case-control study was conducted in which 30 cases of GDM along with age-matched normal glucose tolerance (NGT) pregnant controls were taken. Informed consent was taken and subjects were screened at 24-28th weeks of gestation for GDM by glucose challenge test (GCT), followed by oral glucose tolerance test. Socio-demographic data and clinical evaluation were done using a pre-structured perfoma. Serum concentration of adiponectin and IL-1β was measured using enzyme-linked immunosorbent assay.

Results

The mean value of serum adiponectin level was significantly lower, 5.76 μg/ml SD ± 2.01351 in cases of GDM compared to NGT controls (14.12 μg/dl SD ± 4.99734), P < 0.05. A cutoff value of serum adiponectin level ≤8.7 μg/ml gave a sensitivity and specificity of 100% when used alone for identifying cases of GDM in the present study. Serum level of IL-1β was less than the detectable level (<6.5 pg/ml) in NGT controls. In this study, 26.7% of GDM cases showed levels >6.5 pg/ml (median 18.2 [12.8-34.62]), rest of the cases (73.3%) had levels less than 6.5 pg/ml. A significant inverse correlation was seen between serum adiponectin and HbA1c, pre-gestational BMI, and blood glucose level at GCT. There was no significant correlation of serum IL-1β level with any of the parameters.

Conclusion

GDM is associated with low level of serum adiponectin, and serum adiponectin may be used as a biomarker for detecting cases of GDM to complement blood glucose level.

The utility of HbA1c combined with haematocrit for early screening of gestational diabetes mellitus

AIMS

To evaluate the utility of glycated haemoglobin A1c (HbA1c) alone and in combination with haematocrit (HCT) for screening gestational diabetes mellitus (GDM) between 12-16 gestational weeks.

METHODS

This prospective study was carried out in the Obstetrics and Gynaecology Hospital of Fudan University from November 2014 to February 2015. In total, 690 pregnant women between 20 and 35 years old were included in this study. All subjects received a routine blood examination for HbA1c and HCT at 12-16 gestational weeks (gw) and a 75-g oral glucose tolerance test at 24-28 gw. Threshold values for the diagnosis of GDM were a plasma glucose concentration of 5.1 mmol/L after fasting, 10.0 mmol/L at 60 min, and 8.5 mmol/L at 120 min. Receiver operating characteristic curves were used to evaluate the diagnostic performance of HbA1c with or without HCT.

RESULTS

One hundred seven women were diagnosis with GDM at 24-28 gw. An HbA1c cutoff value < 4.55% at 12-16 gw showed adequate sensitivity to exclude GDM (85.0%) but low specificity (17.3%), while an HbA1c cutoff value ≥ 5.25% presented adequate specificity (96.6%) but low sensitivity (13.3%) in diagnosing GDM. The area under the receiver operating characteristic curve for HbA1c (12-16 gw) detection of GDM was 0.563 (95% confidence interval [CI], 0.50-0.625). When combined HbA1c with HCT ( > 38.8%) for the screening of GDM, the area under the receiver operating characteristic curve was 0.604 (95% [CI] 0.509, 0.701).

CONCLUSIONS

Whether the adoption of HbA1c as a screening test for GDM would benefit pregnant women remains to be determined. However, combining HbA1c with HCT for the screening of GDM may be a useful tool to predict GDM.

The Best Cut-Off Value for HbA1c as a Screening Tool in Iranian Women With Gestational Diabetes Mellitus

Objective: Gestational diabetes mellitus (GDM) is a prevalent disorder which increases maternal and fetal complications. The oral glucose tolerance test (OGTT) is a traditional, time -consuming and intensive test which is poorly tolerated by pregnant women. To date, increasing evidence considered HbA1c as a screening tool and reported various cut-off values in different populations. In alignment with existing literature, we determined for the first time, the optimal cut-off value for HbA1c in Iranian women with GDM. Materials and methods: This case-control study was conducted in Valie-Asr hospital between June 2015 and March 2016. A total of 200 pregnant women who were diagnosed with GDM were selected as study cases. For the control group, 200 healthy women were randomly selected. Fasting blood samples were taken for biochemical analysis, and OGTT was done in all participants. Demographic and anthropometric indexes were measured. Performance of the HbA1c test was analyzed by the Receiver Operating Characteristic (ROC) curve, and the sensitivity and specificity for different HbA1c cut-off points were calculated subsequently. Results: Analysis showed that the mean age (p < 0.001) and BMI (p < 0.001) were significantly higher in the GDM group compared to those in non-GDM pregnant women. GDM participants reported positive family- and previous history of GDM more than healthy pregnant women (p = 0.04 and p < 0.001, respectively). All the markers for Lipid profile were significantly different between the two groups (p = <0.001) except for total cholesterol. The rate of Caesarean section and neonate's Apgar score were not significantly different between the two groups. The best equilibrium between sensitivity (80%) and specificity (76%) for HbA1c was 5.05%. Conclusion: Our results suggest that pregnant women with HbA1c of ≥ 5.05% should proceed with an OGTT. Further investigations with larger sample size are needed to provide more robust evidence for the diagnostic and screening value of HbA1c in identifying pregnant women with GDM.

Comparison of Diagnostic Accuracy of Non-fasting DIPSI and HbA1c with Fasting WHO Criteria for Diagnosis of Gestational Diabetes Mellitus

BACKGROUND

To compare diagnostic accuracy of non-fasting DIPSI and HbA1c with fasting WHO 1999 as gold standard for diagnosis of gestational diabetes mellitus (GDM).

METHODS

Pregnant women attending antenatal clinic underwent a 2-h 75-gm GCT in non-fasting state (DIPSI). HbA1c was also determined at the same sitting. A 2-h 75-gm GCT was repeated for all women after 72 h in a fasting state (WHO criteria). GDM was diagnosed if plasma glucose was ≥140 mg/dl by either test or if HbA1C ≥6%.

RESULTS

Of the 800 women evaluated, 51 were diagnosed as GDM by WHO criteria, 63 by DIPSI, and 40 by HbA1c. The sensitivity of DIPSI test with respect to WHO 1999 was 98.04% and specificity 98.26%. The diagnostic accuracy was 98.25%. The area under the ROC curve for DIPSI was 0.988 (p < 0.001) (95% confidence interval: 0.960-1.000). The sensitivity of HbA1c with respect to WHO GTT was 47.06%, specificity 97.86%, and diagnostic accuracy 94.63%. The ROC curve between WHO GTT and HbA1c covered an area of 0.805 (p < 0.01) (95% confidence interval: 0.731-0.879).

CONCLUSIONS

Non-fasting DIPSI criteria had high diagnostic accuracy compared to gold-standard WHO GTT and can be an effective and practical alternative to the latter. HbA1c had a low sensitivity although the specificity was good and therefore is not a suitable test for screening GDM.

Glycosylated haemoglobin for screening and diagnosis of gestational diabetes mellitus

OBJECTIVES

The oral glucose tolerance test (OGTT) is a cumbersome test that is time consuming, labour intensive and often poorly tolerated by pregnant women. To date, glycosylated haemoglobin (HbA1c) is the most accepted measure of chronic glycaemia outside of pregnancy. HbA1c is an uncomplicated test, less time consuming, does not require any specific patient preparation and is considered straightforward compared with the OGTT. Therefore, we prospectively tested the utility of the HbA1c when used as a screening tool in pregnancy for gestational diabetes mellitus (GDM).

SETTINGS

Primary health care. Single tertiary referral centre, Tasmania, Australia.

PARTICIPANTS

A direct comparison between HbA1c levels and the OGTT results in pregnant women, tested concurrently at the 24-28 gestational week, was undertaken. A full profile of 480 pregnant women during the period from September 2012 to July 2014 was completed. Median and mean age of participants was 29 years (range 18-47 years).

INTERVENTIONS

A simultaneous prospective assessment of HbA1c versus standard OGTT in a cohort of consecutive pregnant women presenting to our institute was performed.

RESULTS

The number of women who had GDM according to OGTT criteria was 57, representing 11.9% of the evaluated 480 pregnant women. Using a cut-off value for HbA1c at 5.1% (32 mmol/mol) for detecting GDM showed sensitivity of 61% and specificity of 68% with negative predictive value (NPV) of 93%, versus sensitivity of 27% and specificity of 95% with NPV of 91% when using HbA1c cut-off value of 5.4% (36 mmol/mol).

CONCLUSIONS

Our results suggest that pregnant women with an HbA1c of≥5.4% (36 mmol/mol) should proceed with an OGTT. This may result in a significant reduction in the burden of testing on both patients and testing facility staff and resources. Further investigations are required to integrate and optimise the HbA1c as a single, non-fasting, screening tool for GDM.

TRIAL REGISTRATION NUMBER

ACTRN12611000739910.

Hemoglobin A1c as screening for gestational diabetes mellitus in Nordic Caucasian women

BACKGROUND

Gestational diabetes mellitus (GDM) increases the risk for preeclampsia and macrosomia. GDM is conventionally diagnosed by an oral glucose tolerance test (OGTT). Hemoglobin A1c (HbA1c) is a marker for the average glucose level the last 2-3 months. We aimed to study if HbA1c alone or in combination with patient characteristics can be used to screen for GDM and reduce the number of OGTTs, and whether it could predict preeclampsia or birth weight.

METHODS

855 women from a previous study on the effect of exercise on GDM prevalence were eligible, whereof 677 were included. GDM was diagnosed by WHO 1999 criteria (GDM-WHO) and modified IADPSG criteria (GDM-IADPSG), at pregnancy weeks 18-22 and 32-36. HbA1c analyzed at pregnancy weeks 18-22 and 32-36, variables from patient history and clinical examination were considered for logistic regression models. The diagnostic accuracy was assessed by ROC curve analysis.

RESULTS

Accumulated GDM prevalence was 6.7 % by WHO and 7.2 % by modified IADPSG criteria. Nearly a third could potentially have avoided an OGTT by using HbA1c to exclude GDM-IADPSG with a sensitivity of 88 % at week 18-22 and 97 % at week 32-36. Further, 16 % could have avoided an OGTT with a sensitivity of 96 % using HbA1c at week 18-22 to exclude GDM-IADPSG throughout pregnancy. HbA1c was not accurate at diagnosing GDM-IADPSG, and it was inaccurate at screening for GDM-WHO at any time point. Adding other predictors did not increase the number of potentially avoidable OGTTs significantly. HbA1c was not significantly associated with preeclampsia or birth weight.

CONCLUSIONS

HbA1c could potentially reduce the number of OGTTs.

HbA1c: A Useful Screening Test for Gestational Diabetes Mellitus

BACKGROUND

Gestational diabetes mellitus (GDM) is associated with adverse maternal and fetal outcomes, and the oral glucose tolerance test (OGTT) is the recommended test for its diagnosis. We evaluated the role of glycated hemoglobin (HbA1c) in screening and diagnosis of GDM and its correlation with adverse pregnancy outcomes.

SUBJECTS AND METHODS

In this prospective observational study, OGTT and HbA1c were performed in 500 antenatal women between 24 and 28 weeks of gestation; the pregnant women were followed up thereafter. Repeat OGTT and HbA1c were done in women with GDM at 6 weeks postpartum.

RESULTS

Among the 500 women, 45 were diagnosed with GDM, for an incidence of 9%. The mean HbA1c level in women with GDM was 6.2 ± 0.6%, whereas it was 5.4 ± 0.5% in those with normoglycemia. Women with GDM had a higher incidence of pregnancy-related complications compared with normoglycemic women. An HbA1c cutoff of 5.3% had a sensitivity of 95.6% and a specificity of 51.6% for the diagnosis of GDM and would have avoided OGTT in approximately half of antenatal women, while missing 5% of the women. However, those with an abnormal HbA1c will require a confirmatory OGTT, as 50% of normoglycemic women would be misclassified as having GDM by this approach. On repeat testing postpartum, two of 45 women (4.4%) had overt diabetes mellitus, whereas five (11.1%) had impaired glucose tolerance.

CONCLUSIONS

Although HbA1c cannot replace OGTT in the diagnosis of GDM, it can be used as a screening test, avoiding OGTT in approximately 50% of women, if a cutoff of 5.3% is used.

HbA1c as screening for gestational diabetes mellitus in women with polycystic ovary syndrome

BACKGROUND

Gestational diabetes mellitus (GDM) is associated with adverse pregnancy outcomes such as preeclampsia and macrosomia. Women with polycystic ovary syndrome (PCOS) are at increased risk of developing GDM. Today, GDM is diagnosed by oral glucose tolerance test (OGTT), a rather cumbersome test for the women and health care system. The objectives of this study were to investigate whether HbA1c in first trimester of pregnancy could be used as a screening test for GDM in first trimester and throughout pregnancy in order to reduce the number of OGTTs, and whether it could predict preeclampsia and macrosomia in women with PCOS.

METHODS

Post hoc analyses of data from 228 women from a prospective, randomised, multicenter study comparing metformin to placebo from first trimester to delivery. Fasting and 2-h plasma glucose were measured during a 75 g OGTT in first trimester, gestational week 19 and 32 as well as fasting plasma glucose in gestational week 36. GDM was diagnosed by WHO criteria from 1999 in first trimester and throughout pregnancy and by modified IADPSG criteria (i.e. lacking the 1-h plasma glucose value) in first trimester. The diagnostic accuracy was assessed by logistic regression and ROC curve analysis.

RESULTS

The area under the ROC curve for first trimester HbA1c for screening of GDM diagnosed by WHO criteria in first trimester was 0.60 (95 % CI 0.44-0.75) and 0.56 (95 % CI 0.47-0.65) for GDM diagnosed throughout pregnancy. Only 2.2 % (95 % CI 0.7-5.1 %) of the participants could have avoided OGTT. HbA1c was not statistically significantly associated with GDM diagnosed by modified IADPSG criteria in first trimester. However, first trimester HbA1c was statistically significantly associated with preeclampsia. Both HbA1c and GDM by WHO criteria in first trimester, but not by IADPSG, were negatively associated with birth weight.

CONCLUSION

First trimester HbA1c can not be used to exclude or predict GDM in women with PCOS, but it might be better to predict preeclampsia than the GDM diagnosis.

Small Molecule Kaempferol Promotes Insulin Sensitivity and Preserved Pancreatic β -Cell Mass in Middle-Aged Obese Diabetic Mice

Insulin resistance and a progressive decline in functional β-cell mass are hallmarks of developing type 2 diabetes (T2D). Thus, searching for natural, low-cost compounds to target these two defects could be a promising strategy to prevent the pathogenesis of T2D. Here, we show that dietary intake of flavonol kaempferol (0.05% in the diet) significantly ameliorated hyperglycemia, hyperinsulinemia, and circulating lipid profile, which were associated with the improved peripheral insulin sensitivity in middle-aged obese mice fed a high-fat (HF) diet. Kaempferol treatment reversed HF diet impaired glucose transport-4 (Glut4) and AMP-dependent protein kinase (AMPK) expression in both muscle and adipose tissues from obese mice. In vitro, kaempferol increased lipolysis and prevented high fatty acid-impaired glucose uptake, glycogen synthesis, AMPK activity, and Glut4 expression in skeletal muscle cells. Using another mouse model of T2D generated by HF diet feeding and low doses of streptozotocin injection, we found that kaempferol treatment significantly improved hyperglycemia, glucose tolerance, and blood insulin levels in obese diabetic mice, which are associated with the improved islet β-cell mass. These results demonstrate that kaempferol may be a naturally occurring anti-diabetic agent by improving peripheral insulin sensitivity and protecting against pancreatic β-cell dysfunction.

A descriptive study of women presenting to an obstetric triage unit with no prenatal care

OBJECTIVE

To describe women presenting to an obstetric triage unit with no prenatal care (PNC), to identify gaps in care, and to compare care provided to World Health Organization (WHO) standards.

METHODS

We reviewed the charts of women who gave birth at Women's Hospital in Winnipeg and were discharged between April 1, 2008, and March 31, 2011, and identified those whose charts were coded with ICD-10 code Z35.3 (inadequate PNC) or who had fewer than 2 PNC visits. Three hundred eighty-two charts were identified, and sociodemographic characteristics, PNC history, investigations, and pregnancy outcomes were recorded. The care provided was compared with WHO guidelines.

RESULTS

One hundred nine women presented to the obstetric triage unit with no PNC; 96 (88.1%) were in the third trimester. Only 39 women (35.8%) received subsequent PNC, with care falling short of WHO standards. Gaps in PNC included missing time-sensitive screening tests, mid-stream urine culture, and Chlamydia and gonorrhea testing. The mean maternal age was 26.1 years, and 93 women (85.3%) were multigravidas. More than one half of the women (51.4%) were involved with Child and Family Services, 64.2% smoked, 33.0% drank alcohol, and 32.1% used illicit drugs during pregnancy. Two thirds of the women (66.2%) lived in inner-city Winnipeg. Only 63.0% of neonates showed growth appropriate for gestational age. Two pregnancies ended in stillbirth; there was one neonatal death, and over one third of the births were preterm.

CONCLUSION

Most women who present with no PNC do so late in pregnancy, proceed to deliver with little or no additional PNC, and have high rates of adverse outcomes. Thus, efforts to improve PNC must focus on facilitating earlier entry into care. This would also improve compliance with WHO guidelines for continuing care. Treatment protocols could improve gaps in obtaining urine culture and in Chlamydia and gonorrhea testing.

Dietary flavonol epicatechin prevents the onset of type 1 diabetes in nonobese diabetic mice

Type 1 diabetes (T1D) is an autoimmune disease characterized by the selective destruction of pancreatic β-cells. Although successful islet transplantation provides a promising treatment, high cost, lack of donor organs, immune-mediated destruction of transplanted islets, and side effects from immunosuppressive drugs greatly limit its uses. Therefore, the search for novel and cost-effective agents that can prevent or ameliorate T1D is extremely important to decrease the burden of T1D. In this study, we discovered that epicatechin (EC, 0.5% in drinking water), a flavonol primarily in cocoa, effectively prevented T1D in nonobese diabetic (NOD) mice. At 32 weeks of age, 66.7% of control mice had overt diabetes, whereas only 16.6% of EC-treated mice became diabetic. Consistently, EC mice had significantly higher plasma insulin levels but lower glycosylated hemoglobin concentrations compared to control mice. EC had no significant effects on food or water intake and body weight gain in NOD mice, suggesting that EC's effect was not due to alterations in these variables. Treatment with EC elevates circulating anti-inflammatory cytokine interleukin-10 levels, ameliorates pancreatic insulitis, and improves pancreatic islet mass. These findings demonstrate that EC may be a novel, plant-derived compound capable of preventing T1D by modulating immune function and thereby preserving islet mass.

Update on diabetes diagnosis: a historical review of the dilemma of the diagnostic utility of glycohemoglobin A1c and a proposal for a combined glucose-A1c diagnostic method

The role of glycohemoglobin A1c (A1c) for the diagnosis of diabetes has been debated for over three decades. Recently, the American Diabetes Association (ADA) has recommended adding A1c as an additional criterion for diabetes diagnosis. In view of the continued debate about the diagnostic utility of A1c, and in view of the unabated burden of undiagnosed diabetes, the search for alternative diagnostic methods is discussed. A historical literature review is provided, in view of the new ADA diagnostic guidelines, and a proposal is provided for combining A1c and a glucose measurement as a diagnostic alternative/adjunct to the use of a single criterion. This proposal is based on the non-overlapping of the advantages and disadvantages of these individual tests. The cost-effectiveness of this method remains to be tested.

Marcadores para o diagnóstico e tratamento de 924 gestações com diabetes melito gestacional

OBJETIVOS: Avaliar o perfil epidemiológico e a evolução de mulheres com diabetes melito gestacional (DMG), determinando fatores de risco para maior vigilância. SUJEITOS E MÉTODOS: Foram estudadas 924 gestações de 916 pacientes, de 6 de novembro de 2001 a 21 de setembro de 2009. RESULTADOS: Foram encontrados fatores de risco para DMG em 95,1% dos casos. A prevalência de diabetes materno, paterno e em outros familiares foi de 24,3%, 9,4% e 24,7%, respectivamente. Os fatores preditivos para uso de insulina foram: glicemia de jejum (GJ) no rastreamento ≥ 85, GJ no Teste Oral de Tolerância à Glicose (TOTG) ≥ 95, glicemia 2h após 75 g de glicose ≥ 200 mg/dL, DMG prévio, obesidade, HbA1c > 6% e história familiar de DM em parente de primeiro grau associada à obesidade ou DMG prévio, esta última a associação mais relevante (p < 0,05). CONCLUSÕES: Os fatores de risco analisados se mostraram altamente sensíveis para a detecção de DMG, e a disposição da história familiar reforça sua relação com o DM2. Recomenda-se maior vigilância a gestantes com fatores preditivos para necessidade de insulina.

Hemoglobin A1c: past, present and future

Hemoglobin A1c (HbA1c) has been used for decades to monitor the control of glycemia in diabetes. Although HbA1cis currently undergoing a reassessment, and major developments have been underway in recent years, HbA1c is not recommended at present for diabetes screening or diagnosis. The objective of this review is to summarize the recent developments and to review a potential diagnostic role for HbA1c. Implementation of changes in HbA1c results and units of measurements have been suggested for the purpose of test standardization. These include lower reference ranges (by about 1.5-2 points) and measurement units expressed in percentage (%), as mg/dL (mmol/L) or mmol/mol (or a combination of these units). In diabetes screening and diagnosis, the current diagnostic guidelines use measurement of plasma glucose either fasting or after glucose load. These diagnostic methods have shortcomings warranting a potential diagnostic role for HbA1c. While recent developments in HbA1c methodologies are acknowledged, it is not yet known which changes will be implemented, and how soon. Given the recent literature supporting HbA1c diagnostic abilities, and given the shortcomings of the current guidelines, it is possible that a diagnostic role for HbA1c may be considered in future practice guidelines, globally. Very recently, the first of such recommendations has been proposed by an expert panel, as announced by the US Endocrine Society.