Implementing care for women with gestational diabetes after delivery-the challenges ahead.

Gestational diabetes (GDM), defined as glucose intolerance during pregnancy, affects one in six pregnancies globally and significantly increases a woman's lifetime risk of type 2 diabetes mellitus (T2DM). Being a relatively young group, women with GDM are also at higher risk of developing diabetes related complications (e.g., cardiovascular disease, non-alcoholic fatty liver disease) later in life. Children of women with GDM are also likely to develop GDM and this perpetuates a cycle of diabetes, escalating our current pandemic of metabolic disease. The global prevalence of GDM has now risen by more than 30% over the last two decades, making it an emerging public health concern. Antepartum management of maternal glucose is unable to fully mitigate the associated lifetime cardiometabolic risk. Thus, efforts may need to focus on improving care for women with GDM during the postpartum period where prevention or therapeutic strategies could be implemented to attenuate progression of GDM to DM and its associated vascular complications. However, strategies to provide care for women in the postpartum period often showed disappointing results. This has led to a missed opportunity to halt the progression of impaired glucose tolerance/impaired fasting glucose to DM in women with GDM. In this review, we examined the challenges in the management of women with GDM after delivery and considered how each of these challenges are defined and could present as a gap in translating evidence to clinical care. We highlighted challenges related to postpartum surveillance, postpartum glucose testing strategies, postpartum risk factor modification, and problems encountered in engagement of patients/providers to implement interventions strategies in women with GDM after delivery. We reasoned that a multisystem approach is needed to address these challenges and to retard progression to DM and cardiovascular disease (CVD) in women with GDM pregnancies. This is very much needed to pave way for an improved, precise, culturally sensitive and wholistic care for women with GDM.

Aging delays the suppression of lipolysis 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-hr 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 post-challenge 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 5-90 min, CHO Rox was significantly lower in older participants. Additionally, FA Rs was significantly lower in older participants at 60 and 90 min. The AUC for FA Rox was greater than that for FA Rs in older, but not 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.

Higher fasting glucose is associated with poorer survival in non-diabetic subjects having ischemia with non-obstructive coronary arteries.

Subjects who have ischemia with non-obstructive coronary arteries (INOCA) experience angina pectoris with evidence of myocardial ischemia but without coronary stenosis. Few studies have investigated factors associated with its survival, especially insulin resistance. In this study, subjects with angina pectoris, without known diabetes mellites (DM), and with non-invasive tests showing myocardial ischemia were admitted for coronary angiography (CAG). Those whose CAG did not reveal stenosis and agreed to receive an oral glucose tolerance test (OGTT) 2 weeks after hospital discharge were enrolled for analysis. All-cause mortality was recorded, which served as the outcome of the study. A total of 587 subjects with INOCA, without known DM, and with OGTT data were analyzed. After OGTT and HbA1c tests, 86 subjects (14.7%) were newly diagnosed with DM and 59.8% had pre-DM. The median duration of follow-up was 7.03 years. Thirty-nine subjects died during the follow-up period. The incidence rate of mortality was 9.9 /1000 person-year. Those who died had a higher fasting glucose (101 ± 17 vs. 94 ± 13 mg/dl, p = 0.003) but a lower estimated glomerular filtration rate (eGFR) (54 ± 22 vs. 87 ± 30 ml/min, p < 0.001). In the Cox survival analysis, a higher fasting glucose (hazard ratio 1.053, p = 0.007) was associated with worse mortality for INOCA without DM (N = 501). On the contrary, a higher eGFR (hazard ratio 0.967, p = 0.012) was protective of better survival for non-diabetic INOCA (N = 501). In conclusion, for non-diabetic INOCA, higher fasting glucose was associated with worse mortality and higher eGFR was protective for better survival.

Incidence of overt diabetes in pregnancy among women with 50-g glucose challenge test ≥ 200 mg/dL.

Objectives: To determine the incidence of overt diabetes in pregnancy (ODIP) among women with 50-g GCT results ≥ 200 mg/dL and compare characteristics and pregnancy outcomes between women with and without gestational diabetes (GDM). Methods: A retrospective cohort study was conducted in 212 pregnant women whose 50-g GCT results ≥ 200 mg/dL. ODIP was diagnosed from 75-g OGTT if fasting plasma glucose ≥ 126 and/or 2-h plasma glucose ≥ 200 mg/dL. Various characteristics and pregnancy outcomes were compared between ODIP and those with and without GDM. Results: Incidence of ODIP was 1.9% of all pregnant women and 23.6% of women with 50-g GCT ≥ 200 mg/dL. Women with ODIP and GDM were more likely to be overweight or obese than those without GDM (52%, 39.6%, and 18.2%, p < 0.001). Women with ODIP had significantly higher 50-g GCT results, lower gestational weight gain, and were less likely to deliver vaginally. Insulin therapy was significantly more common in women with ODIP compared to GDM (70.2% vs. 15.4%, p < 0.001). Rates of LGA, macrosomia, and other neonatal outcomes were comparable. BMI ≥ 25 kg/m2 and 50-g GCT ≥ 240 mg/dL independently increased the risk of any abnormal glucose tolerance [adjusted OR 3.22 (95% CI 1.55-6.70) and 2.28 (95% CI 1.14-4.58)] and ODIP [adjusted OR 9.43 (95% CI 2.15-41.38) and 6.36 (95% CI 2.85-14.18)], respectively. Conclusion: Incidence of ODIP was 23.6% of women with 50-g GCT ≥ 200 mg/dL. BMI ≥ 25 kg/m2 and 50-g GCT ≥ 240 mg/dL independently increased the risk of GDM and ODIP. Neonatal complications were comparable between ODIP and those with and without GDM.

Predicting Type 2 Diabetes Metabolic Phenotypes Using Continuous Glucose Monitoring and a Machine Learning Framework.

Type 2 diabetes (T2D) and prediabetes are classically defined by the level of fasting glucose or surrogates such as hemoglobin HbA1c. This classification does not take into account the heterogeneity in the pathophysiology of glucose dysregulation, the identification of which could inform targeted approaches to diabetes treatment and prevention and/or predict clinical outcomes. We performed gold-standard metabolic tests in a cohort of individuals with early glucose dysregulation and quantified four distinct metabolic subphenotypes known to contribute to glucose dysregulation and T2D: muscle insulin resistance, ß-cell dysfunction, impaired incretin action, and hepatic insulin resistance. We revealed substantial inter-individual heterogeneity, with 34% of individuals exhibiting dominance or co-dominance in muscle and/or liver IR, and 40% exhibiting dominance or co-dominance in ß-cell and/or incretin deficiency. Further, with a frequently-sampled oral glucose tolerance test (OGTT), we developed a novel machine learning framework to predict metabolic subphenotypes using features from the dynamic patterns of the glucose time-series ("shape of the glucose curve"). The glucose time-series features identified insulin resistance, ß-cell deficiency, and incretin defect with auROCs of 95%, 89%, and 88%, respectively. These figures are superior to currently-used estimates. The prediction of muscle insulin resistance and ß-cell deficiency were validated using an independent cohort. We then tested the ability of glucose curves generated by a continuous glucose monitor (CGM) worn during at-home OGTTs to predict insulin resistance and ß-cell deficiency, yielding auROC of 88% and 84%, respectively. We thus demonstrate that the prediabetic state is characterized by metabolic heterogeneity, which can be defined by the shape of the glucose curve during standardized OGTT, performed in a clinical research unit or at-home setting using CGM. The use of at-home CGM to identify muscle insulin resistance and ß-cell deficiency constitutes a practical and scalable method by which to risk stratify individuals with early glucose dysregulation and inform targeted treatment to prevent T2D.

The predictive ability of the triglyceride glucose index, fasting glucose and oral glucose tolerance test for postpartum hyperglycemia in women with a GDM history.

OBJECTIVE: This study aimed to determine the likelihood of hyperglycemia postpartum in women with gestational diabetes mellitus (GDM) and to identify the predictors. METHODS: The retrospective cohort study involved 1 527 GDM patients who delivered at Peking University First Hospital from 1 January 2021, to 31 December 2021. According to the blood glucose level of postpartum oral glucose tolerance test (OGTT), women were divided into a normal glucose tolerance (NGT) group and a hyperglycemia group, and their characteristics and risk factors of hyperglycemia were compared. RESULTS: The prevalence of hyperglycemia was 33.9% (184/543) at 6-12 weeks postpartum. Compared with the NGT group, the fasting plasma glucose (FPG) of hyperglycemia group increased significantly during pregnancy and postpartum, the OGTT 1h postprandial glucose (PG) and 2hPG increased in the second trimester of pregnancy, the triglyceride (TG) increased in the first trimester of pregnancy and postpartum, the triglyceride glucose (TyG) index increased in the first trimester of pregnancy and postpartum, and the total cholesterol (TCHO) and low density lipoprotein cholesterol (LDL-C) decreased in the second trimester (p < 0.05). Fasting plasma glucose (FPG) in the first trimester [odds ratio (OR) = 3.583, p < 0.001], OGTT 2hPG in the second trimester (OR = 1.604, p < 0.001), the TyG index in the first trimester (OR = 1.863, p = 0.045) and FPG in third trimester (OR = 1.985, p = 0.024) were independent risk factors for postpartum hyperglycemia. CONCLUSIONS: Approximately one-third of women with GDM have hyperglycemia 6-12 weeks after delivery. FPG and the TyG index in the first trimester, OGTT 2hPG in the second trimester and FPG in third trimester are risk factors for postpartum hyperglycemia.

Fasting or 2-hour postprandial plasma glycemic criteria for gestational diabetes mellitus are aassociated with distinct adverse outcomes.

OBJECTIVE: We aimed to evaluate the heterogeneity of gestational diabetes mellitus (GDM) patients diagnosed with various screening criteria. METHODS: We stratified pregnant women using consecutive fasting plasma glucose (FPG) and 2-hour postprandial plasma glucose (2hPPG) intervals of 0.2 mmol/L. The incidence of abnormal neonatal birthweight and birth-related adverse outcomes was compared with that of pregnant women without GDM. RESULTS: The study included 39,988 pregnant women (18-45 years, mean [SD], 31.5 [4.7] years) in Ningbo, China. The means (SDs) of FPG and 2hPPG within 24-28 weeks of gestation were 4.5 (0.5) and 6.8 (1.3) mmol/L, respectively. A total of 3025 (7.6%) women had 5.1-6.9 mmol/L FPG and 4560 (11.4%) had 8.5-11.0 mmol/L 2hPPG. The incidence of GDM according to the two combination criteria was 17.3% (6908 cases). The relative risk (RR) for < 10th percentile birthweight (< 10th WT) was 0.82 (95% CI, 0.74-0.91, p < 0.001) by 5.1 mmol/L FPG criterion and 1.14 (95% CI, 1.06-1.23, p < 0.001) by 8.5 mmol/L 2hPPG criterion, while the RRs for > 90th percentile birthweight (> 90th WT) were 1.48 (95% CI, 1.35-1.63, p < 0.001) and 0.95 (95% CI, 0.86-1.04, p = 0.29) according to the corresponding criteria. The FPG criterion was more strongly associated with maternal hypertension than the 2hPPG criterion. Both criteria did not show a distinct association with other composite adverse outcomes. CONCLUSION: High FPG is significantly associated with high birth weight, whereas high 2hPPG is slightly associated with low birth weight. Our findings highlight the heterogeneity of patients with GDM diagnosed by different criteria.

Oral Glucose Tolerance Test for Universal screening for Gestational Diabetes Mellitus.

BACKGROUND: Gestational Diabetes Mellitus increased almost 30% in many countries, including underdeveloped countries and same in Nepal. Hospital-based studies in Nepal reported Gestational Diabetes Mellitus cases, with prevalence 2.48% in 2010 to 4.47% in 2019 emphasising on necessity of universal screening for Gestational Diabetes Mellitus. METHODS: As part of implementation of Electronic Decision support System for Antenatal Care, in formative study clinical vignettes on Gestational Diabetes Mellitus case presented to six healthcare providers ( Incharges, Auxiliary Nurse, Midwives and Lab Assistants) from 3 primary healthcare facilities in Kavre and Dolakha districts, Nepal from October-December 2019. 19 Auxiliary Nurse, Midwives from 19 HCF of 4 districts (Kavre, Dolakha, Sindhuli, and Sindhupalchok, including where clinical vignette were applied trained to perform Oral Glucose Tolerance Test for 4 hours. In-depth Interviews conducted with 16 Auxiliary Nurse, Midwives (8 trained and 8 peer coached from selected 4 HCF to explore their perception and experiences of conducting Oral Glucose Tolerance Test and continuing it for future. Clinical vigenttes compared with PEN protocol and IDIs analyzed thematically. RESULTS: Only 4/6 HCPs made probable diagnosis of Gestational Diabetes Mellitus. 217 Oral Glucose Tolerance Test performed, 24 found to have Gestational Diabetes Mellitus. In-depth Interviews showed Auxiliary Nurse, Midwives enthusiasts on implementing tests for Gestational Diabetes Mellitus and to continue what has been learnt in training. Some challenges; clients hesitate to stay 2 hours at facilities due to unavailability of transport and household work. Oral Glucose Tolerance Test trained Auxiliary Nurse, Midwives seem more confident in counselling and conducting Oral Glucose Tolerance Test than those peer coached. CONCLUSIONS: Administering Oral Glucose Tolerance Test seemed feasible in HCF settings despite some challenges. Training and continuing logistics supply from municipality level seems promising.

Analysis of early-pregnancy metabolome in early- and late-onset gestational diabetes reveals distinct associations with maternal overweight.

AIMS/HYPOTHESIS: It is not known whether the early-pregnancy metabolome differs in patients with early- vs late-onset gestational diabetes mellitus (GDM) stratified by maternal overweight. The aims of this study were to analyse correlations between early-pregnancy metabolites and maternal glycaemic and anthropometric characteristics, and to identify early-pregnancy metabolomic alterations that characterise lean women (BMI <25 kg/m2) and women with overweight (BMI ≥25 kg/m2) with early-onset GDM (E-GDM) or late-onset GDM (L-GDM). METHODS: We performed a nested case-control study within the population-based prospective Early Diagnosis of Diabetes in Pregnancy cohort, comprising 210 participants with GDM (126 early-onset, 84 late-onset) and 209 normoglycaemic control participants matched according to maternal age, BMI class and primiparity. Maternal weight, height and waist circumference were measured at 8-14 weeks' gestation. A 2 h 75 g OGTT was performed at 12-16 weeks' gestation (OGTT1), and women with normal results underwent repeat testing at 24-28 weeks' gestation (OGTT2). Comprehensive metabolomic profiling of fasting serum samples, collected at OGTT1, was performed by untargeted ultra-HPLC-MS. Linear models were applied to study correlations between early-pregnancy metabolites and maternal glucose concentrations during OGTT1, fasting insulin, HOMA-IR, BMI and waist circumference. Early-pregnancy metabolomic features for GDM subtypes (participants stratified by maternal overweight and gestational timepoint at GDM onset) were studied using linear and multivariate models. The false discovery rate was controlled using the Benjamini-Hochberg method. RESULTS: In the total cohort (n=419), the clearest correlation patterns were observed between (1) maternal glucose concentrations and long-chain fatty acids and medium- and long-chain acylcarnitines; (2) maternal BMI and/or waist circumference and long-chain fatty acids, medium- and long-chain acylcarnitines, phospholipids, and aromatic and branched-chain amino acids; and (3) HOMA-IR and/or fasting insulin and L-tyrosine, certain long-chain fatty acids and phospholipids (q<0.001). Univariate analyses of GDM subtypes revealed significant differences (q<0.05) for seven non-glucose metabolites only in overweight women with E-GDM compared with control participants: linolenic acid, oleic acid, docosapentaenoic acid, docosatetraenoic acid and lysophosphatidylcholine 20:4/0:0 abundances were higher, whereas levels of specific phosphatidylcholines (P-16:0/18:2 and 15:0/18:2) were lower. However, multivariate analyses exploring the early-pregnancy metabolome of GDM subtypes showed differential clustering of acylcarnitines and long-chain fatty acids between normal-weight and overweight women with E- and L-GDM. CONCLUSIONS/INTERPRETATION: GDM subtypes show distinct early-pregnancy metabolomic features that correlate with maternal glycaemic and anthropometric characteristics. The patterns identified suggest early-pregnancy disturbances of maternal lipid metabolism, with most alterations observed in overweight women with E-GDM. Our findings highlight the importance of maternal adiposity as the primary target for prevention and treatment.

Sex hormone-binding globulin is a valuable diagnostic indicator of gestational diabetes mellitus.

Objective: To assess the performance of the Sex Hormone-Binding Globulin (SHBG) assay as a diagnostic indicator of Gestational Diabetes Mellitus (GDM) in the study population. Design: Analytical cross-sectional study. Setting: Hospital-based, Benue State University Teaching Hospital (BSUTH), Makurdi, Nigeria. Participants: Women with singleton pregnancies at 24 to 28 weeks gestational age attending Antenatal care at BSUTH, Makurdi. Intervention: Serum SHBG levels were assayed by ELISA during a diagnostic 75-gram Oral Glucose Tolerance Test (OGTT) for assessment of GDM in the cohort of consecutively selected participants who met the inclusion criteria. Main Outcome Measures: Serum levels of SHBG and presence of GDM in the participants. Result: Serum SHBG was significantly negatively correlated (rpb = - 0.534, p-value < 0.001) with the presence of GDM. It had an area under the ROC curve of 0.897 (95% Confidence Interval = 0.858-0.935; p-value < 0.001). A cut-off value of 452.0 nmol/L indicative of GDM had a diagnostic odds ratio of 21.4 in the study population. Conclusion: SHBG is a valuable diagnostic indicator for GDM in the study population. Funding: None declared.

Rise in fasting and dynamic glucagon levels in children and adolescents with obesity is moderate in subjects with impaired fasting glucose but accentuated in subjects with impaired glucose tolerance or type 2 diabetes.

Background: Fasting levels of glucagon are known to be elevated in youth and adults with type 2 diabetes mellitus (T2D). Children and adolescents with obesity were previously reported to show increasing fasting and post-glucose-challenge hyperglucagonemia across the spectrum of glucose tolerance, while no data are available in those with impaired fasting glucose (IFG). Materials and methods: Individuals from the Beta-JUDO study population (Uppsala and Salzburg 2010-2016) (n=101, age 13.3 ± 2.8, m/f =50/51) were included (90 with overweight or obesity, 11 with normal weight). Standardized OGTT were performed and plasma glucose, glucagon and insulin concentrations assessed at baseline, 5, 10, 15, 30, 60, 90 and 120 minutes. Patients were grouped according to their glycemic state in six groups with normal glucose metabolism (NGM) and normal weight (NG-NW), NGM with obesity or overweight (NG-O), impaired glucose tolerance (IGT), impaired fasting glucose (IFG), IGT+IFG and T2D, and in two groups with NGM and impaired glucose metabolism (IGM), for statistical analysis. Results and conclusion: Glucagon concentrations were elevated in young normoglycemic individuals with overweight or obesity (NG-O) compared to normoglycemic individuals with normal weight. Glucagon levels, fasting and dynamic, increased with progressing glycemic deterioration, except in IFG, where levels were comparable to those in NG-O. All glycemic groups showed an overall suppression of glucagon during OGTT. An initial increase of glucagon could be observed in T2D. In T2D, glucagon showed a strong direct linear correlation with plasma glucose levels during OGTT. Glucagon in adolescents, as in adults, may play a role in the disease progression of T2D.

Can the postload-fasting glucose gap be used to determine risk of developing diabetes in chinese adults: A prospective cohort study.

OBJECTIVE: To evaluate the relationship between fasting plasma glucose (FPG) and 2-hour postload plasma glucose (2hPG) measured during an oral glucose tolerance test, and the risk of developing diabetes in Chinese adults. METHODS: We followed 3,094 participants without diabetes, categorizing them based on their oral glucose tolerance test (OGTT) results into low post load (2hPG ≤ FPG) and high post load (2hPG > FPG) at baseline. We monitored the incidence of diabetes, incidence of prediabetes, disease progression from prediabetes to diabetes and disease reversal from prediabetes to normal glucose tolerance (NGT) over an average of 3.2 years of follow-up. After the Schoenfeld residual test, Cox's time-varying covariate (Cox-TVC) models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CI) to compare the different clinical events between low and high post load groups. RESULTS: In the cohort study, of the 3,094 participants, 702 (22.7 %) had low post load (2hPG ≤ FPG, mean postload-fasting gap: -0.8 ± 0.7 mmol/L) and 2,392 (77.3 %) had high post load (2hPG > FPG, mean postload-fasting gap: 1.8 ± 1.2 mmol/L). Over 3.2 ± 0.2 years of follow-up, 282 (9.1 %) developed diabetes. In the low post load group, the incidence rates per 1,000 person-years were: diabetes was 7.9, prediabetes was 70.0, disease progression from prediabetes to diabetes was 23.4 and disease reversal to NGT was 327.2. For the high post load group, incidence rates for diabetes was 13.9, prediabetes was 124.3, disease progression was 59.5 and disease reversal was 238.6 per 1,000 person-years. Participants with high post load showed higher incidence rates of diabetes, prediabetes, and progression from prediabetes to diabetes compared to those with low post load. HRs were significantly higher for incident diabetes and prediabetes, and disease progression from prediabetes to diabetes, whereas disease reversal was lower. CONCLUSION: The risk of developing prediabetes/diabetes after 3.2 years of follow-up was higher in the participants with high post load. It suggested that postload-fasting gap may be a simple tool to predict the risk of developing prediabetes, diabetes or reversal to NGT.

Altered glucose kinetics occurs with aging: a new outlook on metabolic flexibility.

Our purpose was to determine how age affects metabolic flexibility and underlying glucose kinetics in healthy young and older adults. Therefore, glucose and lactate tracers along with pulmonary gas exchange data were used to determine glucose kinetics and respiratory exchange ratios [RER = carbon dioxide production (V̇co2)/oxygen consumption (V̇o2)] during a 2-h 75-g oral glucose tolerance test (OGTT). After an 12-h overnight fast, 28 participants, 15 young (21-35 yr; 7 men and 8 women) and 13 older (60-80 yr; 7 men and 6 women), received venous primed-continuous infusions of [6,6-2H]glucose and [3-13C]lactate with a [Formula: see text] bolus. After a 90-min metabolic stabilization and tracer equilibration period, volunteers underwent an OGTT. Arterialized glucose concentrations ([glucose]) started to rise 15 min post glucose consumption, peaked at 60 min, and remained elevated. As assessed by rates of appearance (Ra) and disposal (Rd) and metabolic clearance rate (MCR), glucose kinetics were suppressed in older compared to young individuals. As well, unlike in young individuals, fractional gluconeogenesis (fGNG) remained elevated in the older population after the oral glucose challenge. Finally, there were no differences in 12-h fasting baseline or peak RER values following an oral glucose challenge in older compared to young men and women, making RER an incomplete measure of metabolic flexibility in the volunteers we evaluated. Our study revealed that glucose kinetics are significantly altered in a healthy aged population after a glucose challenge. Furthermore, those physiological deficits are not detected from changes in RER during an OGTT.NEW & NOTEWORTHY To determine metabolic flexibility in response to an OGTT, we studied healthy young and older men and women to determine glucose kinetics and changes in RER. Compared to young subjects, glucose kinetics were suppressed in older healthy individuals during an OGTT. Surprisingly, the age-related changes in glucose flux were not reflected in RER measurements; thus, RER measurements do not give a complete view of metabolic flexibility in healthy individuals.

The glucose tolerance peak parameter revisited. Definition for a novel use in Gestational Diabetes Mellitus confirmation.

Aims: This study aimed to establish a decisive threshold for the Glucose Tolerance peak (GTp) parameter in diagnosing Gestational Diabetes Mellitus (GDM) and to assess its diagnostic efficacy in comparison with other commonly employed indexes in clinical practice. Materials and methods: Conducted as a prospective observational cohort, the study enrolled 92 pregnant women between 24-28 weeks of gestation, who underwent an Oral glucose Tolerance Test (OGTT) 100 gr. following a positive O'Sullivan screening at La Paz University Hospital. An additional 30-min sample was incorporated to assess the insulin response dynamics during hyperglycaemia. Basal indices and those derived from the OGTT 100 gr. test were computed. Receiver Operating Characteristic (ROC) curves were utilized to determine the optimal cut-off points for the indexes derived from the OGTT. Informed written consent was obtained from all participants. Results: Significantly greater glucose tolerance, as indicated by GTp, was observed in the Non-Gestational Diabetes (NTG) pregnant group (p < 0.01). The GTp emerged as the parameter with the highest positive predictive value for GDM diagnosis. A cut-off of < 0.36 demonstrated 100% specificity and 75% sensitivity in diagnosing GDM. Conclusions: GTp, an index derived exclusively from the OGTT peak glycaemia, proves valuable in confirming the presence of GDM. The GTp could be used to confirm the presence of GDM under necessity of a second OGTT as test confirmation in pregnant woman. A cut-off of < 0. 36 has a specificity of 100% and a sensitivity of 75% for the diagnosis of GDM.

Gestational Diabetes Mellitus Risk Factors in Pregnant Women Attending Public Health Institutions in Ethiopia's Sidama Region: An Unmatched Case-Control Study.

Background: Gestational diabetes mellitus (GDM), a chronic condition leading to glucose intolerance during pregnancy, is common in low- and middle-income countries, posing health risks to both the mother and fetus. Limited studies have been done in Ethiopia, especially using WHO's 2013 universal screening criteria. Therefore, this study aimed to evaluate the risk factors linked to GDM in women attending antenatal (ANC) clinics in Hawassa town public health institutions, located in the Sidama regional state of Ethiopia. Methods: An Unmatched case-control study was carried out in Ethiopia's Sidama Region from April 1st to June 10th, 2023, involving 510 pregnant women. The Oral Glucose Tolerance Test (OGTT) was utilized for universal screening and diagnosing GDM based on the updated 2013 WHO diagnostic criteria. Data analysis included descriptive and analytical statistics, with variables having p-values below 0.1 deemed suitable for bivariate analysis. Statistical significance was assessed using the adjusted odds ratio (AOR) with a 95% confidence interval and a p-value < 0.05. Results: The study involved 633 participants (255 cases and 378 controls), resulting in a 100% response rate, with women having an average age of 29.03 years.Variables such as: age at first conception (AOR=0.97, P=0.01, 95% CI (0.95,0.99)), urban residency (AOR=1.66, P<0.01, 95% CI(01.14,2.40)), widowed marital status (AOR=0.30, P=0.02, 95% CI (0.30,0.90)), parity (AOR=1.10, P<0.01, 95% CI (1.03,1.17)), history of stillbirth (AOR=1.15, P=0.03, 95% CI(1.04,2.30)), and previous cesarean section (AOR=1.86, P=0.01, 95% CI (1.13,2.66)) were identified as independent factors associated with GDM. Conclusion: The study concluded that factors like age at first conception, place of residence, marital status, parity, history of Caesarian section, and stillbirth were independently associated with GDM. Surprisingly, upper arm circumference (MUAC), a proxy for pre-gestational BMI, was not identified as a risk factor for GDM. It is recommended that healthcare providers conduct comprehensive GDM risk assessments in pregnant women to identify and address risk factors, and propose specific screening and intervention strategies.

The Preoperative Paradoxical GH Response to Oral Glucose Load Predicts a low Risk of Recurrence in Acromegaly.

CONTEXT: a paradoxical growth hormone (GH) response to oral glucose load (OGTT) in acromegaly is associated with a milder phenotype. OBJECTIVE: To study whether the GH response to OGTT predicts the risk of recurrence after initial surgical cure. DESIGN: Retrospective, observational study. SETTING: Two tertiary care centers. PATIENTS: We investigated 254 patients with acromegaly who were cured by surgery. INTERVENTION: All patients underwent OGTT at diagnosis before pituitary surgery. A peak-to-basal GH ratio ≥ 120% within 90 minutes was used to distinguish paradoxical (GH-Par) from non-paradoxical acromegalic patients (GH-NPar). MAIN OUTCOME MEASURE: Cox analysis was used to investigate whether the paradoxical GH response to OGTT was associated with the risk of disease recurrence. RESULTS: A paradoxical GH response to OGTT occurred in 87 patients (34.3%, termed GH-Par group). Recurrence of acromegaly occurred in three patients of the GH-Par group (3.4%) and in 20 patients in the GH-NPar group (12.0%). In the multivariate analysis, the paradoxical GH response to OGTT was significantly associated with the risk of recurrence (HR 0.18, 95% CI, 0.05-0.63; P = 0.007). Basal GH level at diagnosis was the only other variable associated with the risk of disease recurrence (HR 1.58, 95% CI, 1.01-2.47; P = 0.04). CONCLUSIONS: our study demonstrates that a paradoxical GH response to OGTT in the preoperative setting predicts a lower risk of disease recurrence after initial surgical cure. The pattern of GH responsiveness to OGTT is, therefore, useful to predict the long-term outcome of patients with acromegaly.

Association Between the Postprandial Response to an Oral Glucose Tolerance Test and Anthropometric Changes After an 8-Week Low-Calorie Formula Diet - Results From the Lifestyle Intervention (LION) Study.

SCOPE: Interindividual variations in postprandial metabolism and weight loss outcomes have been reported. The literature suggests links between postprandial metabolism and weight regulation. Therefore, the study aims to evaluate if postprandial glucose metabolism after a glucose load predicts anthropometric outcomes of a weight loss intervention. METHODS AND RESULTS: Anthropometric data from adults with obesity (18-65 years, body mass index [BMI] 30.0-39.9 kg m-2) are collected pre- and post an 8-week formula-based weight loss intervention. An oral glucose tolerance test (OGTT) is performed at baseline, from which postprandial parameters are derived from glucose and insulin concentrations. Linear regression models explored associations between these parameters and anthropometric changes (∆) postintervention. A random forest model is applied to identify predictive parameters for anthropometric outcomes after intervention. Postprandial parameters after an OGTT of 158 participants (63.3% women, age 45 ± 12, BMI 34.9 ± 2.9 kg m-2) reveal nonsignificant associations with changes in anthropometric parameters after weight loss (p > 0.05). Baseline fat-free mass (FFM) and sex are primary predictors for ∆ FFM [kg]. CONCLUSION: Postprandial glucose metabolism after a glucose load does not predict anthropometric outcomes after short-term weight loss via a formula-based low-calorie diet in adults with obesity.

Antenatal oral glucose tolerance test abnormalities in the prediction of future risk of postpartum diabetes in women with gestational diabetes: Results from the LIVING study.

OBJECTIVES: To explore associations between type and number of abnormal glucose values on antenatal oral glucose tolerance test (OGTT) with postpartum diabetes in South Asian women diagnosed with gestational diabetes (GDM) using International Association of the Diabetes and Pregnancy Study Groups criteria. METHODS: This post-hoc evaluation of the Lifestyle Intervention IN Gestational Diabetes (LIVING) study, a randomized controlled trial, was conducted among women with GDM in the index pregnancy, across 19 centers in Bangladesh, India, and Sri Lanka. Postpartum diabetes (outcome) was defined on OGTT, using American Diabetes Association (ADA) criteria. RESULTS: We report data on 1468 women with GDM, aged 30.9 (5.0) years, and with median (interquartile range) follow-up period of 1.8 (1.4-2.4) years after childbirth following the index pregnancy. We found diabetes in 213 (14.5%) women with an incidence of 8.7 (7.6-10.0)/100 women-years. The lowest incidence rate was 3.8/100 women years, in those with an isolated fasting plasma glucose (FPG) abnormality, and highest was 19.0/100 women years in participants with three abnormal values. The adjusted hazard ratios for two and three abnormal values compared to one abnormal value were 1.73 (95% confidence interval [CI], 1.18-2.54; p = .005) and 3.56 (95% CI, 2.46-5.16; p < .001) respectively. The adjusted hazard ratio for the combined (combination of fasting and postglucose load) abnormalities was 2.61 (95% CI, 1.70-4.00; p < .001), compared to isolated abnormal FPG. CONCLUSIONS: Risk of diabetes varied significantly depending upon the type and number of abnormal values on antenatal OGTT. These data may inform future precision medicine approaches such as risk prediction models in identifying women at higher risk and may guide future targeted interventions.