75-g OGTT Research Articles

Mean Platelet Volume as a Predictive Marker for GDM

Background: Gestational Diabetes Mellitus (GDM) is defined as first onset of any glucose intolerance diagnosed in pregnancy and certain proportion has risk of developing type 2 diabetes later in life, but risk of type 1 is also increased. Screening at the earliest and enhanced diagnostic tools can help reduce burden of GDM and further progression as it is majorly a lifestyle disease. One of the easiest and cost-effective inflammatory markers are thrombocyte indices. Objective: To determine the potential value of MPV, an inexpensive and easy tool obtained from routine complete blood picture used to study morphology of platelet and whether it can be an indicator in prediction of GDM. Methods: Hospital based comparative study was done on 100 antenatal women attending OPD during first trimester. Case group includes women with recently diagnosed GDM as per guidelines of American diabetes Association by one-step 2-hour 75g OGTT and the cut off values were considered as per IADPSG. MPV is assessed amongst cases and controls and its association was studied in both groups. Results: The present study observed that MPV values of the GDM patients were significantly higher than those compared to normal pregnancies. The current investigation reveals that MPV values in GDM patients significantly exceed those observed in normal pregnancies. Specifically, the median MPV in the GDM group is 8.6 (IQR: 6.9-11.2), while in the non-GDM group, it is 7.4 (IQR: 4.8-10.4). The Mann-Whitney U test yielded a statistic of 905, with a corresponding p-value of 0.0175, which falls below the significance threshold of 0.05. Hence, there exists a statistically significant disparity in MPV between the groups. Conclusion: GDM is found to have underlying chronic inflammatory background and varied insulin resistance which states that these parameters may exist even before clinically diagnosable glucose intolerance occurs. This may direct that GTT might not detect GDM if done early in pregnancy, but inflammatory markers might diagnose as they have already been existing. One such economical marker is the MPV as a part of routine CBC. Keywords: Mean Platelet Volume; Gestational Diabetes Mellitus; IADPSG; Exclusive Real World Evidence

Hypoglycaemia following the 2-hour 75g OGTT in pregnancy - investigating maternal and foetal outcomes

Hypoglycaemia following the 2-hour 75g OGTT in pregnancy - investigating maternal and foetal outcomes

Investigation of Serum Cartonectin Concentrations in Pregnant Women with Gestational Diabetes Mellitus; a Prospective Non-Interventional Cohort Study

OBJECTIVE: To investigate serum cartonectin concentrations in pregnant women diagnosed with Gestational Diabetes Mellitus (GDM). STUDY DESIGN: This prospective non-interventional cohort study was conducted on 176 pregnant women. The study group consisted of 88 pregnant women diagnosed with GDM, and the control group consisted of 88 pregnant women with normal 75-g OGTT results. First, the study and control groups, and then the subgroups were compared in terms of serum cartonectin concentrations. RESULTS: The study and control groups were similar in terms of BMI and gestational age at blood sampling (p=0.599, p=0.854). The study and control groups were similar in terms of median serum cartonectin concentrations (6.28 ng/ml and 7.13 ng/ml, respectively, p=0.165). In the subgroup analysis, the normal weight control group, overweight control group, normal weight study group, and overweight study group were compared in terms of serum cartonectin concentrations. The lowest median cartonectin concentration was detected in the overweight study group, followed by the overweight control group, normal weight study group, and normal weight control group (5.8 ng/ml, 6.5 ng/ml, 6.9 ng/ml, and 8.2 ng/ml, respectively, p=0.235). CONCLUSION: Serum cartonectin concentrations were found to be similar in the GDM and control groups. However, the number of participants in this study is limited to draw a definitive conclusion. Many studies with larger series are needed to reveal whether serum cartonectin is involved in the pathophysiology of GDM.

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

To determine the incidence of overt diabetes in pregnancy (ODIP) among women with 50-g GCT results ≥ 200mg/dL and compare characteristics and pregnancy outcomes between women with and without gestational diabetes (GDM). A retrospective cohort study was conducted in 212 pregnant women whose 50-g GCT results ≥ 200mg/dL. ODIP was diagnosed from 75-g OGTT if fasting plasma glucose ≥ 126 and/or 2-h plasma glucose ≥ 200mg/dL. Various characteristics and pregnancy outcomes were compared between ODIP and those with and without GDM. Incidence of ODIP was 1.9% of all pregnant women and 23.6% of women with 50-g GCT ≥ 200mg/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 ≥ 25kg/m2 and 50-g GCT ≥ 240mg/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. Incidence of ODIP was 23.6% of women with 50-g GCT ≥ 200mg/dL. BMI ≥ 25kg/m2 and 50-g GCT ≥ 240mg/dL independently increased the risk of GDM and ODIP. Neonatal complications were comparable between ODIP and those with and without GDM.

Exercise Training Independent of Intensity Lowers Plasma Bile Acids in Prediabetes.

People with obesity have high circulating bile acids (BA). Although aerobic fitness favors low circulating BA, the effect of training intensity before clinically meaningful weight loss on BA is unclear. This study aimed to test the hypothesis that 2 wk of interval (INT) versus continuous (CONT) exercise would lower plasma BA in relation to insulin sensitivity. Twenty-three older adults with prediabetes (ADA criteria) were randomized to 12 work-matched bouts of INT ( n = 11, 60.3 ± 2.4 yr, 32.1 ± 1.2 kg·m -2 ) at 3 min at 50% HR peak and 3 min at 90% HR peak or CONT ( n = 12, 60.8 ± 2.4 yr, 34.0 ± 1.7 kg·m -2 ) at 70% HR peak cycling training for 60 min·d -1 over 2 wk. A 180-min 75-g oral glucose tolerance test (OGTT) was performed to assess glucose tolerance (tAUC), insulin sensitivity (Siis), and metabolic flexibility (RER postprandial -RER fast ; indirect calorimetry). BA ( n = 8 conjugated and 7 unconjugated) were analyzed at 0, 30, and 60 min of the OGTT. Anthropometrics and fitness (V̇O 2peak ) were also assessed. INT and CONT comparably reduced body mass index (BMI; P < 0.001) and fasting RER ( P < 0.001) but raised insulin sensitivity ( P = 0.03). INT increased V̇O 2peak as compared with CONT ( P = 0.01). Exercise decreased the unconjugated BA chenodeoxycholic acid iAUC 60min ( P < 0.001), deoxycholic acid iAUC 60min ( P < 0.001), lithocholic acid iAUC 60min ( P < 0.001), and glycodeoxycholic acid (GCDCA) iAUC 60min ( P < 0.001). Comparable reductions were also seen in the conjugated BA hyodeoxycholic acid iAUC 60min ( P = 0.01) and taurolithocholic acid iAUC 60min ( P = 0.007). Increased V̇O 2peak was associated with lowered UDCA 0min ( r = -0.56, P = 0.02) and cholic acid iAUC 60min ( r = -0.60, P = 0.005), whereas reduced BMI was related to higher GDCA 0min ( r = 0.60, P = 0.005) and GCDCA 0min ( r = 0.53, P = 0.01). Improved insulin sensitivity correlated with lower GCDCA iAUC 60min ( r = -0.45, P = 0.03) and GDCA iAUC 60min ( r = -0.48, P = 0.02), whereas increased metabolic flexibility was related to deoxycholic acid iAUC 60min ( r = 0.64, P = 0.004) and GCDCA iAUC 60min ( r = 0.43, P = 0.05). Short-term training lowers some BA in relation to insulin sensitivity independent of intensity.

Investigation of Serum Cardiotrophin-1 Concentrations in Pregnant Women with Gestational Diabetes Mellitus.

We aimed to investigate cardiotrophin-1 (CT-1) concentrations in the serum of pregnant women with gestational diabetes mellitus (GDM). This prospective non-interventional cohort study was conducted with 160 pregnant women who applied to the Umraniye Training and Research Hospital, Department of Obstetrics and Gynecology between October 2022 and May 2023. The GDM group was formed from 80 pregnant women who were diagnosed with GDM according to the 75-g OGTT. The control group consisted of 80 healthy pregnant women who were matched with the GDM group in terms of age and body mass index and had a normal 75-g OGTT result. Two groups were compared in terms of maternal serum CT-1 concentrations. Both groups were similar in terms of demographic features and the gestational week at blood sampling for CT-1 (p>0.05 for each). The mean maternal serum CT-1 concentration was found to be 1420.9 pg/ml in the GDM group, while it was determined as 1455 pg/ml in the control group (p=0.738). When the GDM and control groups were divided into two subgroups, normal weight and overweight according to the participants' BMI, serum CT-1 concentrations were found to be similar in these four groups (p=0.084). When the GDM group was divided into two groups of diet-only and the insulin-using group for blood glucose regulation and compared with the control group, the three groups were also similar in terms of serum CT-1 concentrations (p=0.189). CT-1 is an adipokine involved in the regulation of glucose metabolism and has been suggested to be associated with the pathophysiology of diabetes mellitus. In this study, serum CT-1 concentrations were found to be similar in the group with GDM and the group with normal glucose tolerance. Whether CT-1 contributes to the development of GDM is currently unclear and requires further investigation.

Employing fasting plasma glucose to safely limit the use of oral glucose tolerance tests in pregnancy: a pooled analysis of four Norwegian studies.

There is no international consensus about the optimal approach to screening and diagnosis of gestational diabetes mellitus (GDM). Fasting plasma glucose (FPG) has been proposed as an alternative universal screening test to simplify the diagnosis of GDM. We investigate the ability of the FPG to predict a 2-hour glucose value below the cut-off for GDM, thereby "ruling out" the necessity of a full OGTT and assess the proportion of GDM-related complications associated with the identified FPG level. This study included secondary data from four Norwegian pregnancy cohorts (2002-2013), encompassing 2960 women universally screened with late mid-pregnancy 75g OGTT measuring FPG and 2-hour glucose. For a range of FPG thresholds, we calculated sensitivity to predict elevated 2-hour glucose, number of OGTTs needed and percentage of GDM cases missed, applying modified World Health Organization (WHO) 2013 criteria (2013WHO) and 2017 Norwegian criteria (2017Norwegian). We analyzed pregnancy outcomes for women above and below our selected threshold. The prevalence of GDM was 16.6% (2013WHO) and 10.1% (2017Norwegian). A FPG threshold of 4.7 mmol/L had a sensitivity of 76% (2013WHO) and 80% (2017Norwegian) for detecting elevated 2-hour glucose, with few missed GDM cases (2.0% of those ruled out and 7.5% of all GDM cases for 2013WHO, and 1.1% of those ruled out and 7% of all GDM cases for 2017Norwegian). When excluding women with FPG <4.7mmol/l and those with GDM based on FPG, only 24% (2013WHO) and 29% (2017Norwegian) would require OGTT. Women with FPG <4.7mmol/l, including missed GDM cases, had low risk of large-for-gestational-age newborns, cesarean section and operative vaginal delivery. A FPG threshold of 4.7mmol/l as a first step when screening for GDM could potentially eliminate the need for OGTT in 70-77% of pregnancies. Women with FPG below this threshold appear to carry low risk of GDM-associated adverse pregnancy outcomes.

Excessive daytime napping independently associated with decreased insulin sensitivity in cross-sectional study - Hyogo Sleep Cardio-Autonomic Atherosclerosis cohort study.

Although excessive daytime napping has been shown to be involved in diabetes occurrence, its impact on insulin secretion and sensitivity has not been elucidated. It is speculated that excessive napping disrupts the sleep-wake rhythm and increases sympathetic nerve activity during the day, resulting in decreased insulin sensitivity, which may be a mechanism leading to development of diabetes. We previously conducted a cross-sectional study that showed an association of autonomic dysfunction with decreased insulin sensitivity, though involvement of autonomic function in the association between napping and insulin sensitivity remained unclear. Furthermore, the effects of napping used to supplement to short nighttime sleep on insulin secretion and sensitivity are also unknown. In the present cross-sectional study, we examined the relationships of daytime nap duration and autonomic function with insulin secretion and sensitivity in 436 subjects enrolled in the Hyogo Sleep Cardio-Autonomic Atherosclerosis (HSCAA) Cohort Study who underwent a 75-g oral glucose tolerance test (75-g OGTT), after excluding those already diagnosed with diabetes. Daytime nap duration was objectively measured using actigraphy, with the subjects divided into the short (≤1 hour) and long (>1 hour) nap groups. Insulin secretion and sensitivity were determined using 75-g OGTT findings. Standard deviation of normal to normal R-R interval (SDNN), a measure of autonomic function, was also determined based on heart rate variability. Subgroup analysis was performed for the associations of napping with insulin secretion and sensitivity, with the results stratified by nighttime sleep duration of less or greater than six hours. Subjects in the long nap group exhibited lower insulin sensitivity parameters (QUICKI: β=-0.135, p<0.01; Matsuda index: β=-0.119, p<0.05) independent of other clinical factors. In contrast, no associations with insulin secretion were found in either group. Furthermore, the association of long nap duration with insulin sensitivity was not confounded by SDNN. Specific subgroup analyses revealed more prominent associations of long nap habit with lower insulin sensitivity in subjects with a short nighttime sleep time (β=-0.137, p<0.05). Long daytime nap duration may be a potential risk factor for decreased insulin sensitivity.

Risk factors of late-onset gestational diabetes diagnosed during 24-28weeks of gestation after normal early screening: a case-control study.

To determine the risk factors associated with late-onset GDM (diagnosed between 24 and 28weeks of gestation) after normal early screening. A case-control study was conducted in 600 singleton pregnant women who started antenatal care before 20weeks with normal early GDM screening. Repeat screening was performed at 24-28weeks. Cases were 120 women with late-onset GDM and 480 controls were those without GDM. Risk factors for late-onset GDM were evaluated and pregnancy outcomes were compared. Cases were significantly older, and more likely to be overweight or obese. 50-g GCT of ≥ 160mg/dL and abnormal 1 value of 100-g OGTT significantly increased the risk of late-onset GDM (p = 0.004 and < 0.001 respectively). Independent risk factors were abnormal 1 value of 100-g OGTT from first screening (adjusted OR 5.49, 95% CI 2.70-11.17, p < 0.001), age ≥ 30years (adjusted OR 2.71, 95% CI 1.66-4.43, p < 0.001), DM in family (adjusted OR 1.76, 95% CI 1.07-2.88, p = 0.025), and BMI ≥ 25kg/m2 (adjusted OR 1.86, 95% CI 1.17-2.97, p = 0.009). Late-onset GDM significantly increased the risk of preeclampsia, cesarean delivery, LGA, and macrosomia. Independent factors associated with late-onset GDM included abnormal 1 value of 100-g OGTT from first screening, age ≥ 30years, DM in family, and being overweight or obese.

Use of fasting plasma glucose to determine the approach for diagnosing gestational diabetes mellitus

AimsEstimate the impact of OGTTs only on women with a screening FPG of 4.5–5.0 mmol/L using data from HAPO. MethodsHAPO participants had 75-g OGTTs (24–32 weeks’ gestation). At follow-up, children had adiposity assessed (overweight/obesity, obesity) and mothers and children had OGTTs. GDM was defined retrospectively using IADPSG criteria. Odds for neonatal (birthweight, percent neonatal fat, sum of skinfolds, cord C-peptide > 90th percentiles) and follow-up outcomes were assessed in those with HAPO FPG ≤ 4.4 or > 4.4 mmol/L and GDM or no GDM focusing on women with FPG > 4.4 and no GDM (Group 3) vs women with GDM and FPG ≤ 4.4 (Group 2). ResultsThis strategy would miss a diagnosis of GDM in 14.7%. Odds for neonatal outcomes in Groups 2 and 3 were not different (ORs: 1.14 to 1.29). Odds at follow-up for type 2 diabetes and disorders of glucose metabolism in mothers were higher in Group 2 (ORs: 3.51, 2.57). Odds for childhood impaired glucose tolerance or adiposity outcomes were not different for Groups 2 and 3. ConclusionsHAPO mothers whose GDM diagnosis would be missed were not at greater risk for adverse neonatal and childhood outcomes than mothers with FPG of 4.5–5.0 without GDM.

THU251 Diagnostic Performance For Predicting Hepatic And Peripheral Tissue Insulin Resistance In Young Adult Men Using 1Hour Post Load Serum Glucose And Insulin Levels A Pilot Study

Abstract Disclosure: A.J. Ledezma: None. C.F. Espinel Pachón: None. S.S. Perea: None. J.E. Caminos: None. Insulin resistance (RI) is a risk factor for prediabetes and DM2, and other non communicable diseases. Different studies have demonstrated that 1h post load serum glucose levels during an oral glucose test tolerance OGTT seem to be a better predictor of peripheral RI than 2h post load serum glucose among individuals without DM2. On the other hand, HOMA IR reflects primarily hepatic sensitivity/resistance, meanwhile, Matsuda index, may reflect both hepatic and peripheral tissue insulin sensitivity/resistance. Thus, this study aimed to evaluate the diagnostic performance, to identify hepatic and peripheral RI, of 1h post load serum glucose and insulin levels during an OGTT in young adult men, using ROC AUC analysis. This cross-sectional study was conducted on a total of 91 young adult men (18-31-year-olds), 47 healthy lean (BMI &amp;lt;25 kg/m2), and 44 obese nondiabetic subjects (BMI ≥30 kg/m2). Subjects underwent a standard 75g OGTT and blood samples were drawn at 0, 30, 60, and 120 min to obtain serum glucose and insulin levels. Clinical and anthropometric and biochemical variables were determined. Participants were classified as RI based on a predefined Matsuda index cutoff 4.3 value. Cut-offs, sensitivity, and specificity for glucose, insulin, and anthropometrics parameters were determined by AUC ROC analysis for predicting RI diagnosis, and Spearman´s correlation was established between biochemical variables and waist/height ratio and Delong test analysis. Our results showed that 1h post load glucose levels had higher sensitivity 84.1% vs 47.7% and AUC 83.9% [CI 95% 75.6; 92.1%] vs 72.4% [CI 95% 61.8%; 83.0%] than 2h post load during OGTT, however lower specificity was found 70.2% vs 89.4%. Additionally, 1h post load insulin levels had higher sensitivity 90.9% vs 77% and AUC 97.1% [CI 95% 94; 100%] vs 91.9% [CI 95% 86.3; 97.5%] than 2h post load during OGTT, without changes in specificity 97.9% vs 97.8%. It is important to highlight that waist/height ratio reached a 100% AUC 95% CI diagnostic performance for RI in our sample. Additionally, HOMA IR index 99.8% [CI 95% 99.1; 100%], 1/fasting insulin 100% [CI 95% 0.99; 100%], and fasting glucose/insulin ratio 99.7% [CI 95% 99.2; 100%], showed a high diagnostic performance for RI. In the Spearman correlation, Waist/height ratio presented a high correlation with respect to Matsuda -0.8672; p&amp;lt;0.01 G/I1H -0.7454; p&amp;lt;0.01, 1/I1H -0.7783; p&amp;lt; 0.01; Delong test, the best performance comparing 1H vs 2H, G1H/G2H with Z value 2.0668 and P 0.03 In conclusion, 1h post load glucose and insulin levels and the waist/height ratio show greater diagnostic performance than 2h post load for detecting peripheral tissue and hepatic RI in young men. Therefore, Cut-offs values of glucose and insulin levels 1h post load provide simple but useful test for early detection of different prevalent diseases related to RI. Presentation: Thursday, June 15, 2023

FRI615 The 1-Hour OGTT Plasma Glucose As A Biomarker Of β-cell Function

Abstract Disclosure: B.T. Legvold: None. A. Zhang: None. K.M. Utzschneider: None. M.K. Rhee: None. L.R. Staimez: None. K.A. Easley: None. M.M. Van Greevenbroek: None. C.J. Van Der Kallen: None. C.G. Schalkwijk: None. C.D. Stehouwer: None. L.S. Phillips: None. Development of diabetes (DM) is attributed to reduced β-cell function, but we lack a measure of β-cell function that is a good predictor of progression to diabetes, and sufficiently convenient and inexpensive for use in large studies. To determine if the 1-hour plasma glucose in a 75g oral glucose tolerance test (1hrOGTT) might serve this purpose, we examined (i) correlations with insulin secretion (insSEC) vs. action (insACT), (ii) prediction of progression from nonDM to DM, and (iii) sample size needed for a prospective trial. The Cohort study of Diabetes and Atherosclerosis Maastricht (CoDAM) included 362 participants with nonDM at baseline who were restudied after 7 years. Incident DM (n=54) was based on American Diabetes Association OGTT cutpoints; insACT included 1/[fasting ins] (I), HOMA2-S (H), and the modified Matsuda Index (M); and insSEC as OGTT Δins/Δglucose0-30min (ISI) and ΔCpep/Δglucose0-30 (CpSI). Since β-cell function reflects insulin secretion relative to insulin action in each individual, we also assessed the disposition index (DI) as insSEC*insACT. (i) Spearman correlations: The 1hrOGTT was correlated with both the 0hrOGTT (0.54) and 2hrOGTT (0.64); weakly with insACT (I, H, and M as 0.31, 0.33, and 0.53, respectively); more strongly with insSEC (ISI and CpSI as 0.54 and 0.67, respectively); and most strongly with DI (ISI*M, CpSI*M, ISI*I, and CpSI*I as −0.89, −0.83, −0.77, and −0.73, respectively); correlations with DI including H were all weaker. (ii) Prediction of progression from nonDM to DM: The area under the receiver operating characteristic curve (ROC) for the 1hrOGTT was 0.84±0.02 (SE), while the ROCs with DI ISI*M, CpSI*M, ISI*I, CpSI*I, ISI*H, and CpSI*H were 0.86, 0.84, 0.85, 0.84, 0.85, and 0.85, respectively. There was no difference between the ROC with the 1hrOGTT and that of the DI models (all p &amp;gt;0.15), while the ROC with the 1hrOGTT was significantly higher than that with most other metrics. (iii) Sample size needed for use in a trial: A side-by-side, two-arm prospective study, with α=0.05 and 80% power to detect a 20% change in β-cell function, would require 26 subjects with the 1hrOGTT, vs. 228 subjects with DI ISI*M. The lower sample size needed reflects lower underlying variance: the coefficient of variation (CV) was 26.7% with the 1hrOGTT, while the CVs for DI ISI*M, CpSI*M, ISI*I, CpSI*I, ISI*H, and CpSI*H were 176.7%, 180.0%, 150.0%, 155.4%, 107.2%, and 90.0%, respectively. Conclusion: The 1-hour 75g OGTT plasma glucose is strongly correlated with the glucose disposition index, and comparable to the disposition index in predicting progression of nonDM to DM, but would require fewer subjects for statistical power in a prospective trial. Since the 1-hour OGTT glucose appears to provide performance similar or superior to more complex and labor-intensive methods, at a greatly reduced cost, consideration should be given to its use as a measure of β-cell function. Presentation: Friday, June 16, 2023

Methods of treating gestational diabetes through an adapted diet and physical activity

Gestational diabetes mellitus (GDM) is a carbohydrate tolerance disorder that results in elevated blood glucose levels and was first recognized during pregnancy. Diabetes is the most common metabolic complication that complicates pregnancy. Therefore, it is important to quickly diagnose and prevent the effects of diabetes, which may arise in the mother and fetus. The occurrence of diabetes during pregnancy is a risk factor for diabetes and cardiovascular diseases later in life. Studies have shown a reduction in complications in patients with gestational diabetes after personalized health education in the field of nutrition. All pregnant women should be screened for impaired glucose tolerance as soon as possible after pregnancy is diagnosed. In the risk group, additionally, a 75g OGTT test should be performed on the first visit. Gestational diabetes affects one in ten pregnant women worldwide, and this percentage is increasing day by day. The main goal is to strive, during therapy, to equalize the glycemic value. The aim of this publication is to present the diagnostic process and, most importantly, the treatment of diabetes diagnosed in pregnancy. The publication focuses on gestational diabetes treated with an adapted diet, exercise and lifestyle changes. This publication describes how to create a balanced diet with a low glycemic index and how to choose physical exercise for a patient with gestational diabetes.

The Validity Of 75gms OGTT For Detection Of GDM Keeping 100gms OGTT As Gold Standard

Objective: To determine the validity of 75gms (Oral Glucose Tolerance Test) OGTT for the detection of GDM keeping 100gms OGTT as the gold standard. Methodology: This was a Cross-sectional validation study done at the Mother and Child Health Centre, Pakistan Institute of Medical Sciences, Islamabad. The duration of the study was Six months from the approval of the synopsis. Data was collected from March 2019 to September 2019. Informed consent for participating in the study was taken from all 205 patients. The patients' bio data along with the hospital registration number was entered pro forma. The patients were assessed initially by History taking and examination. All pregnant women underwent a 75g oral glucose test in the 2nd trimester at 24-28 weeks of gestation. For this, the patients were sent to the MCH laboratory with overnight fasting where FBS was taken and they were given a 75 g glucose drink. Their blood sample was taken at 1-hour and 2-hour interval. Two or more elevated values out of the 3 blood samples were sufficient to diagnose GDM. Laboratory reports were reviewed and data was entered in the performa (attached) by the researcher. All the diagnosed patients were further evaluated for a 100g OGTT dose at the MCH laboratory with overnight fasting. Their FBS was studied and women were given a 100 g glucose drink and blood samples were drawn at an interval of 1, 2 and 3 hours respectively. Out of the 4 blood samples, two or more elevated values were sufficient to diagnose GDM. Lab reports were entered in the Performa. Results: From a total of 205 patients, the sensitivity and specificity of OGTT-75 g for diagnosing GDM were 83.02% and 82.83%. However, positive predictive and negative predictive value for OGTT-75 g was 83.81% and 82% respectively. However, the overall diagnostic accuracy of OGTT-75 g was 82.93%. Conclusion: Results of this study showed that 75 gms OGTT is highly sensitive (83.02%) and specific (82.83%) for the detection/diagnosis of gestational DM. Advanced screening and diagnosis of gestational DM, and its effective treatment not only inhibit adverse perinatal and maternal outcomes but also save the lives of both child and mother from diabetes in future.

Investigation of maternal serum hepassocin concentrations in pregnant women with gestational diabetes mellitus: a prospective case-control study.

We aimed to investigate the relationship between gestational diabetes mellitus (GDM) and maternal serum hepassocin concentrations. This cross-sectional study was conducted with 88 pregnant women who applied to the Ümraniye Training and Research Hospital Gynecology and Obstetrics Clinic between April 2022 and November 2022. The GDM group consisted of 44 pregnant women who had a 75-g OGTT between the 24th and 28th week of pregnancy and were diagnosed with GDM. The control group consisted of 44 healthy pregnant women who were matched with the GDM group in terms of age and body mass index (BMI) and had a normal 75-g OGTT result. Demographic characteristics, laboratory findings, and perinatal outcomes were noted. Two groups were compared in terms of maternal serum hepassocin concentrations. Both groups were similar in terms of age, BMI, weight gain, gravida, parity, polycystic ovary syndrome history, history of diabetes mellitus in the family, and the gestational week at blood sampling for hepassocin (p>0.05 for each). The median maternal serum hepassocin concentration was found to be 18.21 ng/ml in the GDM group, while it was determined as 13.05 ng/ml in the non-GDM group (p=0.012). The GDM group was divided into two groups: the group that only dieted until birth and the group that used insulin until birth for blood glucose regulation. The median hepassocin concentration was found to be 17.99 ng/ml in the diet-only GDM group and 32.15 ng/ml in the insulin-using GDM group. ROC analysis was performed to determine the value of maternal serum hepassocin concentration in predicting GDM. AUC analysis of maternal serum hepassocin for estimation of GDM was 0.656 (p=0.012, 95% CI=0.53-0.77). The optimal threshold value for maternal serum hepassocin concentration was determined as 14.13 ng/ml with 61.4% sensitivity and 61.4% specificity. Serum hepassocin concentration evaluated between 24 and 28 weeks of gestation was found to be higher in pregnant women with GDM than in the non-GDM group. The highest serum hepassocin concentration was found in the GDM group using insulin for blood glucose regulation. Hepassocin seems to be a promising molecule that can be used in GDM screening in pregnant women who do not want to have an OGTT in the future.

1836-PUB: Progression to Prediabetes or Diabetes in Women with Recent Diagnosis of Gestational Diabetes in Mexico

Gestational Diabetes Mellitus (GDM) is a major health concern for Mexican women, with a high prevalence that can lead to long-term consequences if left untreated. The mother's risk of developing diabetes in later life increases by up to 10 times if GDM is not addressed properly and some women may experience Prediabetes or new-onset Diabetes after childbirth. Metabolic reevaluation testing following pregnancy becomes essential for those who have had GDM. Nevertheless, this practice is uncommon. In this study, 1,611 pregnant women were followed during pregnancy, puerperium and at the time of metabolic reevaluation tests following pregnancy for women who have undergone GDM as part of the cohort study Cuido mi Embarazo in Mexico between April 2019 and November 2022. After the follow-up period, 161 (10%) cases of GDM were identified. At the time of the metabolic reevaluation after pregnancy, 136 (84.5%) women were classified as healthy, 21 (13.0%) as having Prediabetes, and 4 (2.5%) with new-onset Diabetes. Glucose values in the 2-h 75-g OGTT for GDM diagnosis were higher for those with impaired glycemia at the moment of metabolic reevaluation. In addition, women with altered glycemia at the time of reclassification tended to be older (32.0 ± 6.2), 52% a phenotypic sub-type of GDM associated with insulin resistance and 24.0% sub-type of GDM associated with insulin resistance and insulin secretion. Moreover, 60.0% had a family history of diabetes, 11.8% had previous pregnancies with newborns who were macrosomic, and 40.0% were obese based on their pregestational BMI category. It is of the utmost importance for all women with GDM to undertake a metabolic reevaluation test that can detect Prediabetes or new-onset Diabetes after pregnancy, so as to initiate immediate treatment and protect women from potential long-term health issues if left unattended. In addition, it becomes imperative that all women with GDM have recurrent screening throughout life due to their high risk of developing Diabetes. Disclosure L.Martinez-juarez: None. H.Gallardo-rincón: None. A.Montoya: None. J.Ortega-montiel: None. D.Álvarez-hernández: None. E.Reyes-muñoz: Speaker's Bureau; Exelixis. R.Mujica-rosales: None. R.Tapia-conyer: None. Funding Eli Lilly and Company

1174-P: Characterization of Glucose Levels in Pregnancy Measured by Blood Glucose Testing or CGM Monitoring after a 50-g Screening or a 75-g or 100-g OGTT

Glucose challenge testing (GCT) is standard diagnostic approach for gestational diabetes (GDM). Using CGM glucose values to characterize glycemia during GCT is not well described. CGM and blood glucose (BG) values were matched with closest CGM value ±5 min of each reported BG time. GDM diagnosed by standard glucose thresholds for 50g GCT, 75g and 100g OGTTs. GCT (n=543, mean gestation 28 wks) showed mean±SD 1 hr BG of 117±28 mg/dL, while matched CGM mean BG was 126±36 mg/dL. The 1 hr BG was ≥135 mg/dL in 24% of GCT vs. 38% by CGM. OGTT (75g) (n=44, mean gestational age 28 wks) showed mean±SD fasting, 1 hr and 2 hr BG of 84±9 mg/dL, 156±33 mg/dL, and 119±26 mg/dL. OGTT (100g) (n=77, mean gestational age 29 wks) showed mean±SD fasting, 1 hr, 2 hr, and 3 hr BG of 82±9 mg/dL, 166±31 mg/dL, 137±27, and 101±27 mg/dL. CGM levels during GCT and both OGTT were similar but slightly higher for each time point; maximum glucose and glucose excursions were also similar between each test vs CGM. Those diagnosed with GDM had consistently higher CGM glucoses than those without GDM (Figure 1). CGM during GCT/OGTT demonstrates CGM correlates to BG, although consistently slightly higher for all 3 glucose tests, regardless of glucose load or timing of measurement. Correlating CGM values to obstetric outcomes would help further describe the role of CGM for diagnosing GDM and improving glucose metabolism in pregnancy. Disclosure A.L.Carlson: Advisory Panel; MannKind Corporation, Novo Nordisk, Research Support; Abbott Diabetes, Dexcom, Inc., Eli Lilly and Company, Medtronic, Novo Nordisk, Insulet Corporation, UnitedHealth Group, Sanofi. J.Sibayan: None. P.Calhoun: None. C.Durnwald: None. R.Beck: Consultant; Eli Lilly and Company, Novo Nordisk, Diasome, Insulet Corporation, Research Support; Tandem Diabetes Care, Inc., Beta Bionics, Inc., Dexcom, Inc., Bigfoot Biomedical, Inc., Medtronic, Ascensia Diabetes Care, Roche Diabetes Care, Eli Lilly and Company, Novo Nordisk. Z.Li: None. E.Norton: None. R.M.Bergenstal: Advisory Panel; Abbott Diabetes, Eli Lilly and Company, Medtronic, Novo Nordisk, Roche Diabetes Care, Zealand Pharma A/S, Consultant; Ascensia Diabetes Care, Bigfoot Biomedical, Inc., CeQur SA, Dexcom, Inc., Hygieia, Onduo LLC, Sanofi, Vertex Pharmaceuticals Incorporated, Research Support; Abbott Diabetes, Dexcom, Inc., Eli Lilly and Company, Insulet Corporation, Medtronic, Novo Nordisk, Sanofi, UnitedHealth Group. M.L.Johnson: Research Support; Abbott, Lilly, Insulet Corporation, NIH - National Institutes of Health, Patient-Centered Outcomes Research Institute, Novo Nordisk, Tandem Diabetes Care, Inc., Medtronic, Hemsley Charitable Trust, Jaeb Center for Health Research. S.Dunnigan: None. M.Banfield: None. K.J.Krumwiede: None. Funding The Leona M. and Harry B. Helmsley Charitable Trust; United Health Group

179-LB: Should We Screen with a Fasting Blood Glucose Test? A Novel Two-Step Screening Strategy for Gestational Diabetes—A Large Tertiary Comparative Cohort Study

Background: Gestational diabetes mellitus (GDM) diagnosis is resource intensive and controversial. A modified COVID-19 GDM diagnostic method was introduced at Western Health Melbourne, an Australian tertiary hospital caring for a multi-ethnic population with a high GDM prevalence at 20-23%. In place of a universal 2 hour 75g OGTT, a novel two step diagnostic method was instituted. A fasting blood glucose (FBG) was performed with thresholds based on a secondary analysis of HAPO data. A FBG of ≥5.1mmol/L (91.8mg/dL) diagnosed GDM; women with FBG 4.7-5.0mmol/L (84.6-90.0mg/dL) proceeded to an OGTT (IADPSG diagnostic criteria); FBG ≤4.6mmol/L (82.8mg/dL) was considered to exclude GDM. Methods: A retrospective cohort study of singleton pregnancies birthing after 20 weeks’ gestation compared perinatal outcomes in 6469 women who underwent modified screening (MS) during the COVID-19 pandemic with 8669 women who had conventional screening (CS) prior to COVID-19. Results: GDM prevalence was the same using either MS or CS (22.9 vs 22.2% p=0.31) with similar rates of insulin use. There was no difference in the prevalence of large for gestational age infants (10.3 vs 9.4% p=0.06), pre-term birth (6.6 vs 6.4% p=0.53) or gestational age at birth (39.2 vs 39.1 weeks). Mean birth weight was increased with MS (3335g vs 3307g) and small for gestational age rate reduced (9.1 vs 10.5% p=0.01). The MS group had fewer inductions (34.2 vs 39.8% p&amp;lt;0.01). Primary caesarean section rate was unchanged (18.4 vs 18.4% p=0.91). MS reduced the need for an OGTT by 76%. Women with a FBG ≤4.6mmol/L by MS had non-inferior outcomes compared to women with a FBG ≤4.6mmol/L with CS irrespective of GDM diagnosis. Conclusion: In a large multi-ethnic cohort with a high prevalence of GDM, modified screening using FBG greatly reduced the number of resource intensive OGTTs with non-inferior perinatal outcomes. A prospective randomised trial comparing these methods is warranted. Disclosure J. Deitch: None. J. M. Said: None. G. R. Teale: None. D. Kevat: Advisory Panel; Novo Nordisk, Speaker's Bureau; Boehringer Ingelheim and Eli Lilly Alliance, Novo Nordisk, Abbott Diabetes, AstraZeneca. I. Lee: None. C. J. Yates: None. E. Kathpal: None. P. Lawton: None. I. Shahid: None. C. Steele: None. P. S. Hamblin: None. B. Krishnamurthy: None. Funding Australian Government Research Training Program; Sheppard Millar Lowe Research Trust Scholarship

193-LB: Refining Diabetes Risk for Individuals with Prediabetes

Rate of progression from prediabetes to diabetes varies greatly, and better risk stratification would help guide prevention efforts. We evaluated predictors of incident diabetes in the placebo arm (n=1212) of the vitamin D and type 2 diabetes (D2d) study. At baseline, participants met 2 or 3 ADA glycemic criteria for prediabetes (fasting glucose, FPG, 100-125mg/dL; 2-hour glucose during a 75-g OGTT, 2hPG, 140-199 mg/dL; HbA1c, 5.7-6.4%). Diabetes was diagnosed based on semiannual testing. After a median follow up of 2.5 years, 27% met criteria for diabetes. Among those who did and did not develop diabetes, mean BMI (±SD) was similar (32.1 kg/m2 ± 4.4), as well as other demographic factors including age, race, and ethnicity. More men than women developed diabetes (29% vs 23%, p=0.02). Incident diabetes rates differed by prediabetes subgroups (Figure); and those meeting all three prediabetes criteria at baseline (35.4%) were most likely to develop diabetes (log-rank p &amp;lt;0.001). There were no differences in the incident diabetes rate among those people meeting only 2 of the prediabetes criteria (Figure). Also, area under the receiver operator characteristic curves for incident diabetes at 36 months increased when all 3 criteria were used in the diagnosis (0.736) vs only FPG and HbA1c (0.686). We conclude that ‘prediabetes’ is heterogeneous, and the 2hPG may refine diabetes risk and guide intervention strategies in adults with high-risk prediabetes. Disclosure S. H. Kim: Advisory Panel; GI Dynamics, Consultant; Aligos, Research Support; Fractyl Health, Inc. D. S. Hsia: None. E. S. Leblanc: Other Relationship; Dexcom, Inc. M. Staten: None. R. Chatterjee montgomery: Research Support; Bristol-Myers Squibb Company, Epigenomics AG. N. Rasouli: Research Support; Novo Nordisk, Eli Lilly and Company, Somalogic. V. R. Aroda: Consultant; Applied Therapeutics Inc., Fractyl Health, Inc., Novo Nordisk, Pfizer Inc., Sanofi, Other Relationship; Janssen Pharmaceuticals, Inc., Research Support; Applied Therapeutics Inc., Eli Lilly and Company, Fractyl Health, Inc., Novo Nordisk, Sanofi. A. G. Pittas: None. Funding National Institutes of Health (U01DK098245)

250-LB: Ethnic Disparities in Insulin Secretion and Clearance in Normoglycemic Adults with Parental Type 2 Diabetes

Background: To determine the role of ethnicity vs. heredity in glucoregulation, we assessed insulin secretion in healthy Black and White offspring of parents with T2DM. Methods: Participants were screened with 75-g OGTT, and normoglycemic enrollees underwent assessments, including anthropometry, insulin sensitivity and secretion. Basal insulin secretion (fasting insulin {FI} and HOMA-B) and dynamic secretion (insulinogenic index; corrected insulin response {CIR} from OGTT data; acute insulin response to i.v. glucose {AIR}, insulin-AUC during FSIGT, and disposition index {DI} were quantified. Insulin sensitivity (ISI) was measured with euglycemic clamp. Basal insulin clearance (molar ratio of fasting C-peptide to insulin) and dynamic clearance (molar ratio of plasma C-peptide to insulin levels during FSIGT) were determined. Results: We studied 145 Black and 123 White adults (N=268); 72% women; mean age 44.6±10.1 y. At baseline, fasting glucose (91.0 ± 7.26 vs.93.1 ± 6.31 mg/dl, P=0.012) and ISI (0.062 ± 0.048 vs. 0.077 ± 0.04, P=.014) were lower, and BMI (31.6 ± 7.64 vs. 28.9 ± 6.79, P=.0032) higher, in Black vs. White subjects. Basal insulin secretion was similar, but all measures of dynamic secretion were higher in Black vs. White offspring (Table 1). Conclusions: Insulin clearance is lower but dynamic insulin secretion is greater in Black versus White individuals with parental diabetes. Disclosure P. Asuzu: None. A. Patel: None. J. Y. Wan: None. S. Dagogo-jack: None.