75-g Oral Glucose Tolerance Test Research Articles

Evaluation of postpartum dysglycemia by serum glycosylated hemoglobin in patients with gestational diabetes mellitus: a national data analysis.

To assess the postpartum sensitivity and accuracy of serum HbA1c levels, compared to the gold standard of 75-g Oral Glucose Tolerance Test (OGTT), for diagnosis of dysglycemia in patients with a history of gestational diabetes mellitus (GDM). A nationwide retrospective analysis of individuals with a history of GDM and with records of both postpartum 2h-OGTT and serum HbA1c measured anytime between delivery until 12months post-delivery. Results were stratified into 3 different intervals: 0-3months, 3-12months, and > 12months after delivery, according to the timing of both OGTT and HbA1c performance. Between January 1st, 2015, until December 31st, 2021, a total of 55,119 individuals were screened, and 9,118 were diagnosed with GDM. Overall, 677 of the 9,118 individuals with GDM had laboratory results of both serum HbA1c levels and 2h 75-gm-OGTT values after delivery. The overall Pearson correlation coefficient between HbA1c and 2h-OGTT was 0.21 (P < 0.0001). However, when the OGTT results were stratified into 2h-glucose values ≥ 200mg/dL, a ROC curve yielded an Area Under the Curve (AUC) of 91.4% [95% CI: 83.9%-98.9%], with HbA1c levels of 5.7% yielding 80.0% sensitivity and 80.8% specificity (95% CI: 44.39-97.48%). In patients with a recent diagnosis of GDM, serum HbA1c may be used as an auxiliary tool for postpartum diagnosis of dysglycemia.

Abstract 4138815: Prognostic Implications of Glycemic Variability Assessed by Continuous Glucose Monitoring-derived Coefficient of Variation among Patients Hospitalized for Acute Heart Failure

Background: Recent findings indicate that high glycemic variability (GV) could increase the risk of adverse outcomes in patients with cardiovascular disease. With the advances in technology, the utility of continuous glucose monitoring (CGM) has grown during recent years, which can provide valuable information that is not captured by HbA1c. We used the glucose coefficient of variation (CV, calculated as the ratio of standard deviation divided by the mean glucose level) of the obtained CGM data to analyze GV. Aims: We aimed to analyze CGM-derived CV as an indicator of GV and to evaluate prognostic implications of CGM-derived CV in patients hospitalized for acute heart failure (HF). Methods: Patients hospitalized for HF who had not been diagnosed diabetes were performed 75g-oral glucose tolerance test (OGTT). CV was evaluated using CGM system for at least 72 consecutive hours after being able to have meals stably during hospitalization. The primary outcome was a composite of cardiovascular death or re-hospitalization for HF. Patients were divided into two groups based on the median value of CV. Results: We prospectively analyzed 130 patients (mean age: 76±10 years, male 56%) admitted for acute HF. Following the 75g-OGTT, only 21% of the entire cohort exhibited normal glucose tolerance. During the median follow up period of 905 days, Kaplan–Meier curve analysis revealed that the cumulative incidence of the primary outcome event was significantly higher in patients with CV above median than in those with CV less than median (51.7% versus 24.4%, Log-rank P=0.01)(Figure). Multivariate Cox proportional analysis demonstrated that the risk of CV per 1% increment for the primary outcome was significant adjusted for history of diabetes, CGM-derived mean glucose level, and HbA1c level (hazard ratio: 1.06, 95% confidence interval 1.03–1.09). Conclusions: CGM-derived CV was associated with long term prognosis of patients hospitalized for HF with or without diabetes.

Aging delays the suppression of lipolysis and fatty acid oxidation in the postprandial period.

Plasma glycerol and free fatty acid concentrations decrease following oral glucose consumption, but changes in the rate of lipolysis during an oral glucose tolerance test (OGTT) have not been documented in conjunction with changes in fatty acid (FA) oxidation or reesterification rates in healthy individuals. After a 12-h overnight fast, 15 young (21-35 yr; 7 men and 8 women) and 14 older (60-80 yr; 7 men and 7 women) participants had the forearm vein catheterized for primed continuous infusion of [1,1,2,3,3-2H]glycerol. A contralateral hand vein was catheterized for arterialized blood sampling. Indirect calorimetry was performed simultaneously to determine total FA and carbohydrate (CHO) oxidation rates (Rox). Total FA reesterification rates (Rs) were estimated from tracer-measured lipolytic and FA oxidation rates. After a 90-min equilibration period, participants underwent a 120-min, 75-g OGTT. Glycerol rate of appearance (Ra), an index of lipolysis, decreased significantly from baseline 5 min postchallenge in young participants and 30 min in older participants. At 60 min, FA Rox decreased in both groups, but was significantly higher in older participants. Between 5 and 90 min, CHO Rox was significantly lower in older participants. In addition, FA Rs was significantly lower in older participants at 60 and 90 min. The area under the curve (AUC) for FA Rox was greater than that for FA Rs in older, but not in young participants. Our results indicate that, in aging, the postprandial suppression of lipolysis and FA oxidation are delayed such that FA oxidation is favored over CHO oxidation and FA reesterification.NEW & NOTEWORTHY To our knowledge, our investigation is the first to demonstrate changes in lipolysis during an oral glucose tolerance test (OGTT) in healthy young and older individuals. Plasma glycerol and free fatty acid concentrations changed after glycerol rate of appearance (Ra), indicating that plasma concentrations are incomplete surrogates of the lipolytic rate. Moreover, simultaneous determinations of substrate oxidation rates are interpreted to indicate that metabolic inflexibility in aging is characterized by delayed changes in postprandial substrate utilization related to the lipolytic rate.

Heterogeneity of gestational diabetes and risk for adverse pregnancy outcome: a cohort study.

Diabetes has increasingly been recognized as a heterogeneous disease, with clinical characteristics and outcomes risk varying across different phenotypes. Evidence on heterogeneity of gestational diabetes (GDM) is yet to be provided. To investigate the insulin physiology and pregnancy outcomes of GDM phenotypes characterized by fasting hyperglycemia or postload hyperglycemia. A total of 2050 women who underwent a 75-g oral glucose tolerance test were prospectively recruited and followed up until delivery. Women were categorized into normoglycemia (NGT, n = 936), isolated impaired fasting glucose (gestational-IFG, n = 378), and isolated impaired postload glucose tolerance (gestational-IGT, n = 736) groups. Fasting blood sample at mid-pregnancy were collected to measure C-peptide and insulin concentrations. Homeostasis model assessment (HOMA) and quantitative insulin sensitivity check index (QUICKI) were used to evaluate insulin physiology. Maternal and neonatal outcomes were recorded. Gestational-IFG had greater insulin resistance (HOMA-IR 3.11 vs. 2.25, QUICKI-CP 0.94 vs. 1.03, both P < 0.01), and gestational-IGT had worse β-cell function (C-peptide 2.00 vs. 2.26 ng/ml, P < 0.05) when compared to one another. Gestational-IFG was more strongly associated with excessive gestational weight gain (RR 1.62, 95% CI 1.18-2.23) and large-for-gestational-age infants (RR 1.45, 95% CI 1.03-2.03) than gestational-IGT. The risk for neonatal brain injury was increased in gestational-IGT (RR 2.03, 95% CI 1.04-4.09), but not in gestational-IFG (P = 0.439). Gestational-IGT showed a stronger association with the risk of preterm birth compared to gestational-IFG (RR 1.80, 95% CI 1.02-3.36). GDM exhibits distinct insulin physiology profiles. Pregnancy outcome varies between each phenotype. These findings provide evidence on risk stratification and diverse strategies for the treatment of GDM.

1-hour postload glucose is a more sensitive marker of impaired β-cell function than 2-hour postload glucose.

There is evidence that 1-h plasma glucose (PG) during the 75-g oral glucose tolerance test (OGTT) is superior to 2-h PG in predicting diabetes. We aimed to investigate the characteristics of insulin sensitivity and β-cell function behind this observation. After age, sex and BMI matching, 496 subjects selected from 3965 non-diabetic individuals at high risk of type 2 diabetes in a tertiary medical center were categorized into four groups in a 1:1:1:1 ratio based on OGTT results: 1) 1 h < 8.6 mmol/L and 2 h < 7.8 mmol/L (normal glucose tolerance [NGT] /1h-normal); 2) 1 h ≥ 8.6 mmol/L and 2 h < 7.8 mmol/L (NGT/1h-high); 3) 1 h < 8.6 mmol/L and 2 h ≥ 7.8 mmol/L (impaired glucose tolerance [IGT]/1h-normal); and 4) 1 h ≥ 8.6 mmol/L and 2 h ≥ 7.8 mmol/L (IGT/1h-high). Compared with subjects with IGT/1h-normal, those with NGT/1h-high exhibited similar extent of insulin resistance but lower early-phase insulin secretion. Additionally, participants with NGT/1h-high had lower disposition index at both 0-30 min and 0-120 min than those with IGT/1h-normal. The fitted regression line relating PG to log-transformed disposition index (0-30 min and 0-120 min) was significantly steeper for 1-h than 2-h PG. In conclusion, 1-h PG seemed to be more sensitive to the deterioration in β-cell function than 2-h PG. The use of 1-h PG may identify individuals at high risk of type 2 diabetes at an earlier stage.

Microbiome-derived metabolites in early to mid-pregnancy and risk of gestational diabetes: a metabolome-wide association study

BackgroundPre-diagnostic disturbances in the microbiome-derived metabolome have been associated with an increased risk of diabetes in non-pregnant populations. However, the roles of microbiome-derived metabolites, the end-products of microbial metabolism, in gestational diabetes (GDM) remain understudied. We examined the prospective association of microbiome-derived metabolites in early to mid-pregnancy with GDM risk in a diverse population.MethodsWe conducted a prospective discovery and validation study, including a case–control sample of 91 GDM and 180 non-GDM individuals within the multi-racial/ethnic The Pregnancy Environment and Lifestyle Study (PETALS) as the discovery set, a random sample from the PETALS (42 GDM, 372 non-GDM) as validation set 1, and a case–control sample (35 GDM, 70 non-GDM) from the Gestational Weight Gain and Optimal Wellness randomized controlled trial as validation set 2. We measured untargeted fasting serum metabolomics at gestational weeks (GW) 10–13 and 16–19 by gas chromatography/time-of-flight mass spectrometry (TOF–MS), liquid chromatography (LC)/quadrupole TOF–MS, and hydrophilic interaction LC/quadrupole TOF–MS. GDM was diagnosed using the 3-h, 100-g oral glucose tolerance test according to the Carpenter-Coustan criteria around GW 24–28.ResultsAmong 1362 annotated compounds, we identified 140 of gut microbiome metabolism origin. Multivariate enrichment analysis illustrated that carbocyclic acids and branched-chain amino acid clusters at GW 10–13 and the unsaturated fatty acids cluster at GW 16–19 were positively associated with GDM risk (FDR < 0.05). At GW 10–13, the prediction model that combined conventional risk factors and LASSO-selected microbiome-derived metabolites significantly outperformed the model with only conventional risk factors including fasting glucose (discovery AUC: 0.884 vs. 0.691; validation 1: 0.945 vs. 0.731; validation 2: 0.987 vs. 0.717; all P < 0.01). At GW 16–19, similar results were observed (discovery AUC: 0.802 vs. 0.691, P < 0.01; validation 1: 0.826 vs. 0.780; P = 0.10).ConclusionsDysbiosis in microbiome-derived metabolites is present early in pregnancy among individuals progressing to GDM.

Is early pregnancy hemoglobin A1c useful to predict gestational diabetes mellitus diagnosed during mid pregnancy?

To verify whether hemoglobin A1c (HbA1c) levels in early pregnancy can predict the diagnosis of gestational diabetes mellitus (GDM) in mid-pregnancy. This was a retrospective cohort study of 2008 pregnant women who delivered singletons at the Yokohama City university Medical Center. Concomitant or history of diabetes mellitus and overt diabetes in pregnancy were excluded. Pregnant women at high risk for GDM underwent a one-step 75-g oral glucose tolerance test (OGTT) during mid-pregnancy. For other pregnant women, GDM was diagnosed by a two-step 75-g oral glucose tolerance test (OGTT) when the 50-g glucose challenge test result in mid-pregnancy was ≥140 mg/dL. The thresholds for 75-g OGTT followed those of the International Association of Diabetes and Pregnancy Study Group (IADPSG) criteria (92-180-153 mg/dL). The relationship between HbA1c level measured at <20 weeks of gestation and GDM diagnosis at mid pregnancy was assessed using a receiver operating characteristic curve (ROC); area under the curve (AUC) and optimal cutoff value of HbA1c, predictive of GDM were calculated. The median HbA1c level at <20 weeks of gestation was 5.3%, and 8.5% of women were diagnosed with GDM. In the ROC curve of the GDM diagnosis rate by HbA1c level, AUC was 0.706, and the optimal cutoff value was 5.4%, with a sensitivity of 0.6176, specificity of 0.6834, positive predictive value of 15.4%, and negative predictive value of 95.1%. Although HbA1c at less than 20 weeks of gestation is acceptable discrimination as a diagnostic tool of GDM in mid-pregnancy, it is not clinically useful to predict GDM in mid-pregnancy.

7252 Difference between interstitial and blood glucose during glucose loading is associated with the degree of insulin resistance in subjects with prediabetes and type 2 diabetes

Abstract Disclosure: D. Kim: None. S. Ryang: None. M. Im: None. J. Kim: None. Y. Kim: None. Y. kim: None. J. ha: None. J. Kim: None. S. Kim: None. Background and Aims: This study investigated the main factors responsible for the differences between blood glucose (BG) and interstitial fluid glucose (ISF) during glucose loading. Methods: A total of 204 Korean subjects without history of type 2 diabetes were enrolled. The subjects were categorized into three groups according to diabetes criteria by American Diabetes Association; NGT (normal glucose tolerance, n=36), PreDM (prediabetes, n=130) and T2D (undiagnosed type 2 diabetes, n=38). For glucose monitoring, a CGM (continuous glucose monitoring) system (Dexcom G6, Dexcom, San Diego, USA) was attached for 10 days. 75g oral glucose tolerance test (OGTT) was performed during applying CGM with stabilization (after wear of 3 days). Blood sample collected at t=0, 30, 60, 90 and 120 min for glucose and insulin concentration. Two parameters [insulin sensitivity (mIS) and beta-cell function (mBCF)] were derived novel mathematical model. Results: Among NGT, PreDM and T2D, there are heterogeneity in the difference and pattern between BG and ISF in this study. We identified the probability density function of BG - ISF across glucose tolerance, there is a trend that the means of BG - ISF with G60, 90, and 120 move to the right, as glucose tolerance status changes NGT to PreDM and DM. BG - ISF is significantly associated with insulin resistance (R=0.32, p&amp;lt;0.001), not diminished beta cell function. Conclusions: Because individuals vary in their degree of insulin resistance as a primary pathophysiology of type 2 diabetes, the caution should be needed in interpreting the glycemic response of CGM after a glucose load. Presentation: 6/3/2024

6900 Fetal Abdominal Obesity in Women Exhibiting One Abnormal Value on Diagnostic Testing for Gestational Diabetes Mellitus

Abstract Disclosure: W. Kim: None. S. Park: None. Y. Kim: None. Background: Fetal abdominal obesity (FAO) was already observed at the time of diagnosis of GDM in our previous study. We investigated whether fetuses of women with hyperglycemia milder than GDM showed accelerated abdominal growth, leading to adverse pregnancy outcomes. Methods: We retrospectively reviewed the medical records of 7,569 singleton pregnant women who were universally screened using a 50-g glucose challenge test (GCT) and underwent a 3-h 100-g oral glucose tolerance test (OGTT) if GCT result was ≥140mg/dL. GDM, one value abnormality (OVA), and normal glucose tolerance (NGT, NGT1: GCT negative, NGT2: GCT positive &amp; OGTT negative) were diagnosed using Carpenter-Coustan criteria. With fetal biometry data measured simultaneously with 50-g GCT, relative fetal abdominal overgrowth was investigated by assessing the fetal abdominal overgrowth ratios (FAORs) of the ultrasonographically estimated gestational age (GA) of abdominal circumference(AC) per actual GA by the last menstruation period(LMP), biparietal diameter (BPD) or femur length(FL), respectively. FAO was defined as FAOR ≥90th percentile Results: The FAORs of GA-AC/GA-LMP and GA-AC/GA-BPD were significantly higher in OVA subjects compared to NGT subjects but not in NGT2 subjects. Although the frequency of FAO in OVA (12.1%) was between that of NGT (9.6%) and GDM (18.3%) without statistically significant difference, the prevalence of large for gestational age at birth and primary cesarean delivery rates were significantly higher in OVA (9.8% and 29.7%) than in NGT (5.1% and 21.5%, p&amp;lt;0.05). Particularly, among OVA subjects with FAO, the prevalence (33.3% and 66.7%) was significantly higher than in those without FAO (9.7% and 24.2%, p&amp;lt;0.05). Conclusion: The degree of fetal abdominal growth acceleration in OVA subjects was intermediate between that of NGT and GDM subjects. OVA subjects with FAO at the time of GDM diagnosis were strongly associated with adverse pregnancy outcomes. Presentation: 6/2/2024

Postpartum Glucose Follow-up Screening Among Women With Gestational Diabetes Mellitus: A Retrospective Cohort Study

Abstract Objective To evaluate the impact of pre-gestational and gestational characteristics on postpartum glucose follow-up screening (PGFS) compliance in women diagnosed with gestational diabetes mellitus (GDM) in southwest China. Methods This retrospective cohort study was conducted in West China Second Hospital, Sichuan University. Pre-gestational and gestational factors were extracted from hospital records and compared between women who completed PGFS and those who did not. The screening method chosen was the 75g oral glucose tolerance test (OGTT), performed 4–12 weeks postpartum. Univariate analysis, logistic regression analysis, and Cochran-Armitage test were used to assess associations between maternal characteristics and PGFS compliance. Results A total of 3047 women with GDM were included, with a PGFS completion rate of 47.2%. Of those who completed PGFS, 430 women (29.9%) presented abnormal results: 1.8% with impaired fasting glucose (IFG), 24.1% with impaired glucose tolerance (IGT), 2.2% with both IFG and IGT 2.2%, and 1.8% with suspected diabetes. Independent factors associated with non-compliance to PGFS included higher pre-gestational BMI (odds ratio (OR): 0.952; 95% confidence interval (CI): 0.922, 0.984), multipara (OR: 0.721; 95% CI: 0.593, 0.877), use of assisted reproduction technology (ART) (OR: 1.427; 95% CI: 1.080, 1.885), excessive gestational weight gain (OR: 0.956; 95% CI: 0.936, 0.977), elevated fasting plasma glucose (FPG) prior to delivery (OR: 0.909; 95% CI: 0.835, 0.988), and undergoing cesarean section (OR: 1.232; 95% CI: 1.017, 1.492) were independent influencing factors of failing to PGFS. PGFS completion rates significantly decreased with increasing pre-gestational BMI and earlier gestational age (P &lt; 0.001). Conclusions Establishing dedicated postpartum follow-up teams and targeting women with higher pre-gestational BMI, multiparity, ART use, excessive gestational weight gain, elevated pre-delivery FPG, and those undergoing cesarean section are critical to improving postpartum GDM management.

Utilization of a Postpartum Fasting Blood Glucose to Predict Impaired Glucose Tolerance in Patients with Gestational Diabetes Mellitus.

The Endocrine Society recommends a postpartum fasting blood glucose (FBG) be performed for patients with gestational diabetes mellitus (GDM) prior to hospital discharge to screen for ongoing hyperglycemia. There are limited data, however, on whether an FBG can screen for glucose intolerance and if it correlates with the gold standard 4- to 12-week 2-hour oral glucose tolerance test (OGTT). Our objective was to evaluate if FBG correlates with the gold standard 2-hour OGTT. This retrospective cohort study of patients with GDM who delivered >20 weeks' gestation at two urban centers from January 2017 to December 2020 included those who completed both a postpartum FBG prior to discharge and a 2-hour 75-g OGTT within 1 year of delivery. Abnormal 2-hour OGTT was defined as fasting value ≥100 mg/dL and/or 2-hour value ≥140 mg/dL. We evaluated test characteristics (e.g., sensitivity, specificity) of postpartum FBG cut-offs to predict an abnormal 2-hour OGTT result. A total of 235 patients met inclusion criteria, of which 63% were diet-controlled and 37% required medical management. FBG ranged from 64 to 134 mg/dL, with 6/235 (2.6%) with values ≥126 mg/dL. A total of 39/235 (16.6%) of patients had an abnormal 2-hour OGTT. Overall, area under the curve for FBG predicting abnormal 2-hour OGTT was 0.65. Traditionally considered high cut-offs (≥126 mg/dL) for predicting persistent impaired glucose intolerance demonstrated poor positive predictive value (PPV; <20%). In contrast, low cut-offs demonstrated excellent NPV (>90%). A postpartum FBG of 88 mg/dL was determined to be the optimal cut-off for FBG with NPV = 92.4% (Youden index = 0.34). In this dataset, if FBG ≥ 88 mg/dL was used to determine if 2-hour OGTT was required, almost half of GDM patients could avoid further glucose tolerance testing. While previously thought of as best utilized for its PPV, the FBG may be best used for its NPV. In our study, clinical application of an FBG < 88 mg/dL was highly correlative with a normal 2-hour OGTT. · Screening for postpartum glucose intolerance is essential for gestational diabetes.. · A promising initiative includes offering screening tests while in the hospital, including an FBG.. · Application of a postpartum FBG < 88 mg/dL is highly correlative with a normal 2-hour OGTT..

Rationale and Design of the Study to Investigate the Metabolic Action of Imeglimin on Patients with Type2 Diabetes Mellitus (SISIMAI).

Imeglimin is a first-in-class, novel, oral glucose-lowering agent for the treatment of type2 diabetes mellitus. The efficacy and safety of imeglimin as an antidiabetic agent have been investigated in clinical trials. However, its metabolic effects in humans have not yet been fully elucidated. The Study to InveStIgate the Metabolic Action of Imeglimin on patients with type2 diabetes mellitus (SISIMAI) is a single-arm intervention study. In this study, we have recruited 25 patients with type2 diabetes to receive 2000mg/day imeglimin for 20weeks. We perform a 75-g oral glucose tolerance test (OGTT) with double-glucose tracers, a two-step hyperinsulinemic-euglycemic clamp with glucose tracer, ectopic fat measurement by proton magnetic resonance spectroscopy, visceral/subcutaneous fat area measurement by magnetic resonance imaging, muscle biopsy, and evaluation of fitness level by cycle ergometer before and after imeglimin administration. The primary outcome is the change in area under the curve of glucose levels during the OGTT after 20weeks of imeglimin treatment. We also calculate the endogenous glucose production, rate of oral glucose appearance, and rate of glucose disappearance from the data during the 75-g OGTT and compare them between pre- and post-treatment. Additionally, we will compare other parameters, such as the changes in tissue-specific insulin sensitivity, ectopic fat accumulation, visceral/subcutaneous fat area accumulation, and fitness level between each point. This is the first study to investigate the organ-specific metabolic action of imeglimin in patients with type2 diabetes mellitus using the 75-g OGTT with the double tracer method. The results of this study are expected to provide useful information for drug selection based on the pathophysiology of individual patients with type2 diabetes mellitus. jRCTs031210600.

The impact of an oral glucose load on IFN-γ-release in persons infected with Mycobacterium tuberculosis

Background and objectiveTo diagnose tuberculosis infection (TBI), whole blood is incubated with M.tuberculosis (Mtb)-specific peptides and the release of interferon-γ (IFN-γ) is measured in IFN-γ-release assays (IGRAs). Hyperglycaemia and fluctuations in blood glucose may modulate IFN-γ-release. Here, we investigated if glucose intake affects IFN-γ-release or IGRA results in IGRAs taken during an oral glucose tolerance test (OGTT).MethodsPersons with TB disease (TB) or TBI underwent a standard 75-g OGTT at the start and end of treatment for TB or TBI. Blood for the IGRA QuantiFERON-TB Gold Plus (QFT) containing Mtb-specific tubes (TB1 and TB2), a non-specific mitogen tube (MIT) and an empty control tube (NIL) was drawn at sample-timepoints -15 (baseline), 60, 90, 120 and 240 min during the OGTT. Blood glucose was measured in parallel at all timepoints. IFN-γ-release (after subtraction of NIL) at each timepoint was compared with baseline using linear-mixed-model analysis.ResultsTwenty-four OGTTs from 14 participants were included in the final analysis. Compared to baseline, IFN-γ-release was increased at sample-timepoint 240 min for TB1; geometric mean (95% confidence interval) 3.0 (1.5–6.2) vs 2.5 (1.4–4.4) IU/mL (p = 0.047), and MIT; 182.6 (103.3–322.9) vs 146.0 (84.0–254.1) IU/mL (p = 0.002). Plasma glucose levels were not associated with IFN-γ-release and the QFT test results were unaffected by the OGTT.ConclusionIngestion of glucose after a 10-h fast was associated with increased IFN-γ-release after 240 min in the MIT tube. However, there was no association between plasma glucose levels at the QFT sampling timepoint and IFN-γ-release. Furthermore, the QFT test results were not affected by glucose intake. The overall effect of an OGTT and prevailing plasma glucose levels on IFN-γ-release in IGRAs seem limited.Trial registrationTrial registration ID: NCT04830462 (https://clinicaltrials.gov/study/NCT04830462). Registration date: 05-Apr-2021.

Relationship Between Average Glucose Levels and HbA1c Differs Across Racial Groups: A Substudy of the GRADE Randomized Trial.

To determine whether the relationship between average glucose (AG) levels and hemoglobin A1c (HbA1c) differs across racial/ethnic groups. We performed a prospective substudy of GRADE, a comparative effectiveness randomized trial conducted in 36 centers in the U.S. A total of 1,454 of the 5,047 participants in the GRADE cohort, including 534 non-Hispanic White (NHW), 389 non-Hispanic Black (NHB), and 327 Hispanic White patients and 204 patients of other racial/ethnic backgrounds, were included in the substudy. Continuous glucose monitoring (CGM) performed for 10 days was used to calculate AG10. Immediately after CGM, HbA1c and glycated albumin were measured. Fasting plasma glucose (FPG) and glucose area under the curve (AUC) were derived from a 75-g oral glucose tolerance test. The relationship between AG10 and HbA1c was significantly different for NHB compared with NHW patients and those of other racial/ethnic groups. HbA1c levels were 0.2-0.6 percentage points higher in NHB than in NHW patients for AG10 levels from 100 to 250 mg/dL. For an HbA1c of 7%, AG10 was 11 mg/dL higher for NHW than for NHB patients. Similar findings were observed across races for relationships of FPG and AUC with HbA1c and for glucose measurements with glycated albumin levels. Differences in the relationship between AG10 and HbA1c across racial groups remained after adjustments for any demographic or other differences between racial/ethnic subgroups. The relationship between several measures of glucose with HbA1c and glycated albumin consistently differed across races. These findings should be considered in setting treatment goals and diagnostic levels.

The Implications of a "Flat" Oral Glucose Tolerance Test Curve in Pregnancy.

To determine whether pregnant women with "flat" oral glucose tolerance test (OGTT) curves are at increased risk of adverse perinatal outcomes. We conducted a retrospective cohort study comparing the perinatal outcomes of pregnant women whose 100g OGTT curve was "flat" (fasting serum glucose below 95 mg/dl and the remaining values below 100 mg/dl) to those of women whose OGTT curve was "normal". Primary outcomes compared were the prevalence of macrosomic and small for gestational age (SGA) neonates. Secondary outcomes included hypertensive disorders of pregnancy (HDP), intrauterine fetal demise, placental abruption, induction of labor, meconium-stained amniotic fluid (MSAF), mode of delivery, postpartum hemorrhage (PPH), blood product transfusion, postpartum readmission, umbilical artery pH <7.1, Apgar score <7 at 5 minutes, neonatal intensive care unit (NICU) admission, neonatal respiratory and infectious morbidity, and hypoglycemia. Composite adverse maternal and neonatal outcomes were also evaluated. There were 1,060 patients in the study group and 10,591 patients in the control group. Patients with a flat OGTT had a reduced risk of delivering a macrosomic neonate (11.4% vs. 15.1% OR 0.7 [0.58-0.89] p=0.001) and having an unplanned cesarean delivery (7.5% vs 10.2% OR 0.8 [0.58-0.96] p=0.002). There was no difference in the rate of composite adverse maternal (14.0% vs 15.4% OR 0.9 [0.7-1.0] p=0.1) or neonatal outcome (5.3% vs. 4.5% OR 1.2 [0.9-1.5] p=0.15). Neonates had a slightly lower mean birthweight (3474g vs. 3505g, p=0.04), but the rate of SGA was similar in the two groups (2.5% vs.1.8% OR 1.3[0.9-2.0] p=0.08). Conclusions Pregnant women whose OGTT curve is flat have a lower risk of delivering macrosomic neonates and undergoing unplanned cesarean delivery and are not at increased risk of adverse maternal or neonatal outcomes. More research is required to evaluate the relationship between different OGTT curves and th.

Problems in screening for gestational diabetes mellitus by measurement of casual blood glucose levels at 24-28 gestational weeks.

This study aimed to evaluate the problems in screening for gestational diabetes mellitus (GDM) by casual blood glucose (CBG) measurements at 24-28 gestational weeks. Overall, 763 pregnant women who underwent the 50-g glucose challenge test (GCT) at 24-28 gestational weeks were enrolled. The preload blood glucose (0-h BG) level of 50-g GCT was considered as CBG. A total of 240 women with BG levels at 1-h after loading (1-h BG) on 50-g GCT ≥140 mg/dL underwent the 75-g oral glucose tolerance test, and 98 (40.8%) were diagnosed with GDM. Of the 99 women with GDM, 71 (71.7%) had 0-h BG on 50-g GCT <100 mg/dL. This study, where pregnant women underwent both CBG and 50-g GCT simultaneously, showed that when CBG at 24-28 gestational weeks ≥100 mg/dL alone was used for screening GDM, many pregnant women with GDM were overlooked.

Single Dose of Phosphatidylinositol 3-Kinase Inhibitor Alpelisib Induces Insulin Resistance in Healthy Adults: A Randomized Feasibility Study.

Our objective is to test a single dose of the phosphoinositide-3-kinase (PI3K) inhibitor alpelisib as a tool for acute modeling of insulin resistance in healthy volunteers. This single-center, double-blind, phase 1 clinical trial randomized healthy adults to take a single oral dose of alpelisib 300 mg (n = 5) or placebo (n = 6) at bedtime, followed by measurement of glucose, insulin, and C-peptide levels after an overnight fast and during a 3-hour, 75-g oral glucose tolerance test. Fasting plasma glucose trended higher with alpelisib (mean ± S.D.: 93 ± 11 mg/dL) versus placebo (84 ± 5 mg/dL), while mean fasting serum insulin increased nearly fivefold (23 ± 12 µU/mL vs. 5 ± 3 µU/mL, respectively) and Homeostasis Model Assessment of Insulin Resistance scored 5.4 ± 3.1 for alpelisib and 1.1 ± 0.6 for placebo. During OGTT, incremental area under the curve (AUC) for insulin was over fourfold greater with alpelisib (22 ± 15 mU/mL x min) than placebo (5 ± 2 mU/mL x min); glucose AUC trended higher with alpelisib. Single-dose alpelisib was well tolerated and produced metabolic alterations consistent with acute induction of IR, validating its use for mechanistic study of insulin action in humans. (ClinicalTrials.gov registration: NCT05733455).

Impact of hematocrit levels on the accuracy of specific blood glucose meters: Ahospital-based study.

Blood glucose meters are commonly used at the bedside, but most of the meters used in Hung Vuong Hospital (Ho Chi Minh City, Vietnam) are built for self-monitoring and might not be suitable for determining glucose levels in patients. In this study, we aimed to validate the performance of six frequently used meters in our hospital using the Clinical & Laboratory Standards Institute (CLSI) standard, and investigate the hematocrit impact on the accuracy of these meters. A total of 135 pregnant women who underwent a 75-g oral glucose tolerance test consented to participate in the study at Hung Vuong Hospital. Whole blood glucose levels were measured in duplicate using meters, and hematocrit levels were measured using an Alinity h-series analyzer. Within 5 min, plasma glucose levels were measured twice in a row using the Cobas c502 reference analyzer. For accuracy and precision, the hematocrit effect was assed using CLSI POCT12-A3. Out of six evaluated meters, three meters qualified. For CLSI criterion at glucose concentration of 5.55 mmol/L, Accu-Chek Inform II, Accu-Chek Performa and OneTouch VerioVue achieved 97.31%, 98.08% and 99.62%, respectively. For CLSI criterion at 4.17 mmol/L, these three achieved 100%. Accu-Chek Inform II and Accu-Chek Performa showed an inverse correlation between glucose level and hematocrit with slopes of -0.500 (95% confidence interval -0.678 to -0.322) and -0.396 (95% confidence interval -0.569 to -0.224), whereas OneTouch VerioVue was not affected by hematocrit, with a slope of 0.207 (95% confidence interval -0.026 to 0.440). Blood glucose meters' measurements can be affected by hematocrit, and might provide readings not within an acceptable bias. Medical organizations need to verify or validate before using on patients.

Relationship Between Early-Pregnancy Glycemia and Adverse Outcomes: Findings From the TOBOGM Study.

We evaluated associations between early-pregnancy oral glucose tolerance test (OGTT) glucose and complications in the Treatment of Booking Gestational Diabetes Mellitus (TOBOGM) cohort to inform prognostic OGTT thresholds. Individuals with risk factors for hyperglycemia were recruited for an international, multicenter, randomized controlled gestational diabetes mellitus (GDM) (World Health Organization 2013 criteria) treatment trial. A 2-h 75-g OGTT was performed at <20 weeks' gestation. Individuals with early treated hyperglycemia in pregnancy were excluded from the primary analysis. Early OGTT glucose concentrations were analyzed continuously and in glycemic categories (normal, low band, and high band). Overall, 3,645 individuals had an OGTT at (mean ± SD) 15.6 ± 2.5 weeks. For each 1-SD increase in fasting, 1-h, and 2-h glucose values, there were continuous positive associations with late GDM: adjusted odds ratio (aOR) 2.04 (95% CI 1.82-2.27), 3.05 (2.72-3.43), and 2.21 (1.99-2.45), respectively. There were continuous positive associations between 1-h and 2-h glucose and the perinatal composite (birth <37 + 0 weeks, birth trauma, birth weight ≥4,500 g, respiratory distress, phototherapy requirement, stillbirth/neonatal death, and shoulder dystocia), with aOR 1.15 (95% CI 1.04-1.26) and 1.14 (1.04-1.25), respectively, and with large-for-gestational-age offspring, with aOR 1.18 (1.06-1.31) and 1.26 (1.01-1.25), respectively. Significant associations were also observed between 1-h glucose and cesarean section and between fasting and 2-h glucose and neonatal hypoglycemia. In categorical analysis, only the high-band 1-h glucose (≥10.6 mmol/L [191 mg/dL]) predicted the perinatal composite. There is a continuous positive association between early-pregnancy OGTT glucose and complications. In individuals with hyperglycemia risk factors, only the high-glycemic-band 1-h glucose corresponded to increased risk of major perinatal complications.

Postpartum glucose intolerance after gestational diabetes mellitus: tailored prediction according to data-driven clusters and BMI-categories.

To account for the heterogeneity of gestational diabetes (GDM), this study investigated tailored predictors during pregnancy and at 6-8 weeks postpartum of glucose intolerance (GI) at 1-year postpartum. We identified predictors according to data-driven clusters, analogous to the newly proposed diabetes classification, and for clinical ease also based on BMI-categories. This is a secondary analysis of the MySweetheart trial. It included 179 women with GDM who underwent a 75g oral glucose tolerance test and HbA1c measurement at 1-year postpartum. Predictors were determined according to: a) cluster analysis based on age, BMI, HOMA-IR and HOMA-B; and b) BMI-categories (normal weight [NW], and overweight/obesity [OW/OB]). We identified two clusters during pregnancy and at 6-8 weeks postpartum (for both time points an "insulin-resistant", and an "insulin-deficient" cluster). The "insulin-resistant" cluster was associated with a 2.9-fold (CI: 1.46-5.87; pregnancy) and 3.5-fold (CI: 1.63-7.52; at 6-8 weeks postpartum) increased risk of GI at 1-year postpartum. During pregnancy, the most relevant predictors of GI were history of previous GDM and fasting glucose for the "insulin-deficient" and NW category and HOMA-IR for the "insulin-resistant" and OW/OB category (all p ≤0.035). In the postpartum, predictors were more heterogenous and included the insulin-sensitivity-adjusted-secretion index and 1-h glucose in the "insulin-deficient" and NW women. In women with GDM, we identified "insulin-resistant" and "insulin-deficient" clusters with distinct risks of future GI. Predictors varied according to clusters or BMI-categories emphasizing the need for tailored risk assessments.