Short-term reproducibility of impaired fasting glycaemia, impaired glucose tolerance and diabetes The ADDITION study, DK

Continuous glucose monitoring and intrapersonal variability in fasting glucose

Plasma fasting glucose (FG) levels play a pivotal role in the diagnosis of prediabetes and diabetes worldwide. Here we investigated FG values using continuous glucose monitoring (CGM) devices in nondiabetic adults aged 40-70 years. FG was measured during 59,565 morning windows of 8,315 individuals (7.16 ± 3.17 days per participant). Mean FG was 96.2 ± 12.87 mg dl-1, rising by 0.234 mg dl-1 per year with age. Intraperson, day-to-day variability expressed as FG standard deviation was 7.52 ± 4.31 mg dl-1. As there are currently no CGM-based criteria for diabetes diagnosis, we analyzed the potential implications of this variability on the classification of glycemic status based on current plasma FG-based diagnostic guidelines. Among 5,328 individuals who would have been considered to have normal FG based on the first FG measurement, 40% and 3% would have been reclassified as having glucose in the prediabetes and diabetes ranges, respectively, based on sequential measurements throughout the study. Finally, we revealed associations between mean FG and various clinical measures. Our findings suggest that careful consideration is necessary when interpreting FG as substantial intraperson variability exists and highlight the potential impact of using CGM data to refine glycemic status assessment.

Associations of MTHFR Polymorphisms and Cytosine Modifications with Early-Gestational Diabetes Mellitus in Chinese Pregnant Women

Early-Gestational Diabetes Mellitus (Early-GDM) is a complex condition that may cause complications in infants of affected mothers. The aim of this case-control study was to analyze the effects of genetic-epigenetic interaction on Early-GDM and fetal development with respect to cytosine modifications (i.e., 5mC, 5-methylcytosines; and 5hmC, 5-hydroxymethylcytosines) and single nucleotide polymorphisms (SNPs) of MTHFR, a key gene involving cytosine modifications. Peripheral blood samples were collected from 92 women in their first or second trimester of pregnancy (Early-GDM, n = 14; Controls, n = 78). Global DNA 5mC and 5hmC were quantified by HPLC-MS/MS, and MTHFR SNPs (rs1801133 C > T and rs1801131 A > C) were determined by TaqMan-qPCR. Association analysis suggested that MTHFR rs1801133 TT genotype was a risk factor of Early-GDM (OR [odds ratio] = 4.00; 95% CI [confidence interval]: 1.24, 12.86; p = 0.02). The C allele of rs1801131 appeared to be a protective factor for the 2-h OGTT (oral glucose tolerance test) (OR = -0.79; 95% CI: -1.48, -0.10; p = 0.03). Patients with Early-GDM had higher global 5mC and lower global 5hmC. The reduction of global 5hmC and the TT genotype of rs1801133 were associated with higher level of the 1st-FBG (fasting blood glucose in the first trimester) (p < 0.05). Additionally, global 5mC showed a positive correlation with birth weight, body length and head circumference of newborns, while global 5hmC showed a negative correlation with birth weight. The current study implicated MTHFR SNPs and cytosine modifications in the development of Early-GDM and potential complications in their newborns.

A multicenter prospective study of early gestational diabetes mellitus: rates, severity and risk factors based on IADPSG defined fasting glycemia

OBJECTIVE

To describe the epidemiology of early gestational diabetes mellitus (GDM) based on the International Association of Diabetes and Pregnancy Study Groups (IADPSG) defined fasting glycemia MATERIALS AND METHODS: A prospective multicenter study testing fasting venous plasma glucose (FPG) in women aged 18 - 45 years between 6 - 23 6/7 weeks gestation in secondary health facilities in Ondo State, Nigeria. Early GDM was defined using the IADPSG threshold for fasting hyperglycemia, and its severity was examined. Potential risk factors for early GDM were assessed using logistic regression analysis.

RESULTS

Of the 8915 women who underwent FPG testing, the prevalence of early GDM was 12.5% (11.9 - 13.3). Multivariable analysis identified a dose-response association between body mass index (BMI) (kg/m² ) and early GDM, with a BMI ≥35kg/m² (aOR 1.92, 95% CI 1.03-3.55) associated with early GDM. Primiparity (aOR 1.49, 95%CI 1.25-1.76), multiparity (aOR 1.73, 95%CI 1.47-2.04) and a first-degree family history of diabetes (aOR 1.60, 95%CI 1.27-2.02) were associated with significantly higher odds of early GDM.

CONCLUSION

This study established the prevalence, severity and risk factors for early GDM in a specific country that potentially represents a global region with no previous relevant data.

Why some pregnant women refuse glucose challenge test? Turkish pregnant women's perspectives for gestational diabetes mellitus screening

OBJECTIVE

Diabetes in pregnancy is associated with several adverse outcomes for both mother and baby. Awareness is the first step toward identifying pregnant women with diabetes. The purpose of this study was to assess Turkish pregnant women's opinion and practice about 50-g glucose challenge test (GCT) and to assess the reasons why some of them refuse the test.

METHODS

This study was conducted on 312 patients at any age and gestational week in Istanbul, Turkey, by a personal interview using self-created questionnaire. Women were asked about their opinion and practice about 50-g GCT.

RESULTS

Among women who were ≤28 weeks of gestation, 42.5% (n=82/193) exhibited their desire to have a GCT in their ongoing pregnancy, 40.9% (n=79/193) pointed out their reluctance, and 16.6% (n=32/193) indicated that they had no opinion about the subject. Women who were ≤28 weeks of gestation and did not want to have GCT, were asked to explain the reasons of their reluctance. The most frequently indicated reason was the belief that GCT is harmful for their babies and themselves (n=62/79, 78.5%). Of the women who were >28 weeks of gestation, 37.8% (n=45/119) had GCT in the ongoing pregnancy, while 62.2% (n=74/119) did not have GCT. The most frequently indicated reason why women did not have a GCT was the belief that GCT is harmful for themselves and the baby (n=37/74, 50%).

CONCLUSION

This study exposes an important problem - misinformation about 50-g GCT - that carries a dangerous potential for missing the diagnosis of gestational diabetes. Study findings put forth the need for raising awareness among pregnant women and training health-care professionals about the subject.

Possibility to predict early postpartum glucose abnormality following gestational diabetes mellitus based on the results of routine mid-gestational screening

INTRODUCTION

Women with previous gestational diabetes mellitus (GDM) have increased risk of developing glucose abnormality, but current diagnostic criteria are evidence-based for adverse pregnancy outcome.

THE AIMS OF OUR STUDY WERE

(i) to ascertain a frequency of early conversion of GDM into permanent glucose abnormality, (ii) to determine predictive potential of current GDM diagnostic criteria for prediction of postpartum glucose abnormality and (iii) to find optimal cut-off values of oral glucose tolerance test (oGTT) to stratify GDM population according to postpartum risk.

MATERIALS AND METHODS

Electronic medical records of an ethnically homogenous cohort of women diagnosed and treated for GDM in a single medical centre during the period 2005-2011 who completed postpartum oGTT up to 1 year after the index delivery were retrospectively analysed (N=305).

RESULTS

Postpartum glucose abnormality was detected in 16.7% subjects. Mid-trimester oGTT values, respective area under the curve and HbA1c were significantly associated with early postpartum glucose abnormality (P<0.05, Mann-Whitney) and exhibited significant predictive potential for postpartum glucose abnormality risk assessment. Optimal cut-off values for discrimination of at-risk sub-population were identified using ROC analysis and their comparison with WHO and IADPSG criteria exhibited superiority of IADPSG for risk-stratification of GDM population.

CONCLUSION

Risk-based stratification at the time of GDM diagnosis could improve efficiency of the post-gestational screening for diabetes. IADPSG criteria seem to optimally capture both perinatal and maternal metabolic risks and are therefore medically and economically justified.

Hemoglobin A1c as a tool for the diagnosis of type 2 diabetes in 208 premenopausal women with polycystic ovary syndrome

OBJECTIVE

To study hemoglobin A1c (HbA1c) as a tool for diagnosing diabetes and to study HbA1c as a cardiovascular risk marker in patients with polycystic ovary syndrome (PCOS).

DESIGN

Retrospective observational study.

SETTING

Academic tertiary-care medical center.

PATIENT(S)

Two hundred eight premenopausal women with PCOS.

INTERVENTION(S)

Patients underwent clinical evaluation (Ferriman-Gallwey score, body mass index, waist, blood pressure), hormone analyses (T, sex hormone-binding globulin, fasting lipids, insulin, glucose, HbA1c), transvaginal ultrasound, and 2-hour oral glucose tolerance tests (OGTT) measuring capillary blood glucose (BG) at 0 (BG 0) and 120 (BG 120) minutes, insulin, and C-peptide.

MAIN OUTCOME MEASURE(S)

Results of OGTT, HbA1c values.

RESULT(S)

Twenty patients were diagnosed with type 2 diabetes during OGTT. The sensitivity and specificity of HbA1c ≥6.5% for the diagnosis of diabetes were 35% and 99%, respectively, compared with the diagnosis established by OGTT. Hemoglobin A1c showed closer correlation with waist, body mass index, and lipid profile than BG 120, suggesting that HbA1c could be a cardiovascular risk marker.

CONCLUSION(S)

The clinical utility of HbA1c for diagnosing impaired glucose tolerance and type 2 diabetes in PCOS in daily practice is low. Long-term prospective studies are needed to determine whether HbA1c is superior to glucose levels as a cardiovascular risk marker in patients with PCOS.

The usefulness and cost of a shorter duration of fasting in workplace screening for glucose intolerance and metabolic syndrome

For worksite biometric screening, we shortened traditional fasting instructions to 4h. The positive predictive value (PPV) of elevated capillary glucose test results (> or =100mg/dL) for predicting elevated values obtained on repeat testing after an 8h fast was 57%, which rivals the PPV of an 8h fasting glucose.