Lower glycemia levels in subjects with excessive erythrocytosis during the oral glucose tolerance test living in conditions of severe hypoxia.

Background: Previous studies showed that residents of higher elevations have lower glucose levels. Our objective in this study is to determine the basal and postprandial glucose levels in apparently healthy permanent residents of the miner population center of La Rinconada located 5100 meters (m) above sea level. Method: Forty male permanent residents of the Rinconada miner population center were studied. The oral glucose tolerance test was used to evaluate basal and postprandial glycemia levels at 1, 2, and 3 h. Results: The individuals had a mean age of 43.95 ± 8.54 years. Basal glycemia in subjects without excessive erythrocytosis (EE) was 73.3 ± 7.9 mg/dL, while levels in patients with EE were 57.98 ± 7.38 mg/dL. In the postprandial period, at 1 h after oral glucose overload, a mean value of 76.35 ± 13.53 mg/dL was observed in subjects with EE compared to 94.68 ± 9.98 mg/dL in subjects without EE. After 2 h, subjects with EE had a glycemia level of 72.91 ± 9.17 mg/dL EE compared to 90.73 ± 13.86 mg/dL without EE. At 3 h, the average glycemia level in subjects with EE was 70.77 ± 8.73 mg/dL compared to 87.79 ± 14.16 mg/dL in those without EE. Conclusion: These findings suggest that under hypoxic conditions, glycemia levels are lower in both subjects with and without EE, having obtained lower levels in subjects with EE in relation to those with normal values of Hb and Hct. The results of this study indicate that in the conditions of severe hypoxia, blood glucose levels are below the values considered normal for sea level.

Efficacy of a phone reminder to improve adherence to post-partum glucose tolerance testing after gestational diabetes and clinical predictors of post-partum follow-up compliance.

AIM: To assess the effectiveness of a phone reminder to improve adherence to post-partum glucose tolerance testing in women with gestational diabetes mellitus (GDM) and to identify clinical predictors of adherence to post-partum follow-up. METHODS: Retrospective study including 543 women with GDM. We assessed the adherence rate to post-partum glucose tolerance testing in women who received a phone reminder (n = 297) compared to women not alerted (n = 246). Demographic and clinical variables were collected to identify the predictors of adherence to the post-partum oral glucose tolerance test (OGTT). RESULTS: The adherence to post-partum OGTT was higher in women who received the phone reminder compared to those not alerted (60.6 % vs. 35.4 %, p < 0.001). Women less compliant compared to those more compliant, had a higher pre-pregnancy body mass index (BMI) (29.3 ± 7.9 vs. 27.0 ± 6.1 Kg/m2, p = 0.03). The adherence was lower in pre-pregnant obese compared to non-obese women (42.7 % vs. 52.0 %, p < 0.05), in women with only one, compared to multiple OGTT alterations during pregnancy (44.5 % vs. 57.8 %, p < 0.05), and in women non-insulin treated compared to those insulin-treated (40.0 % vs. 57.1 % vs, p < 0.001). CONCLUSIONS: The phone reminder improved post-partum follow-up adherence. Pre-pregnancy BMI, number of OGTT alterations and type of therapy could identify poorly adherent women.

One abnormal value in oral glucose tolerance test during pregnancy and type 2 diabetes risk: Insights from a 5-Year Follow-Up study.

OBJECTIVES: To evaluate the risk of type 2 diabetes(T2D) following one abnormal value(OAbV) in an oral glucose tolerance test(oGTT) performed during pregnancy. STUDY DESIGN: A retrospective analysis of parturients between 01.01.2017 and 31.12.2020 with 5 years of follow-up after delivery. Glucose levels during pregnancy were extracted from the computerized laboratory system of Meuhedet HMO and cross-tabulated with the Israeli National Registry of Diabetes. Women with multiple gestations or pregestational diabetes were excluded. Maternal characteristics and risk of T2D were stratified and compared between 3 groups: normal glucose status, OAbV in oGTT, and gestational diabetes. Statistical analysis included univariate analysis followed by survival analysis. Further analysis was stratified to women with and without obesity. RESULTS: 58,693 women entered the analysis. Following an adjustment to maternal age, obesity, hypertension, and hyperlipidemia, OAbV in oGTT was associated with a 1.8-fold increased risk of T2D in a 5-year follow-up compared to normal glucose status. When stratified by obesity, OAbV was associated with a 3.7-fold increase in T2D in women without obesity, however, was no longer a statistically significant predictor of T2D among women with obesity. CONCLUSIONS: Women with OAbV oGTT during pregnancy are at increased risk for developing T2D over 5 years of follow-up.

Utilizing the Glucose and Insulin Response Shape of an Oral Glucose Tolerance Test to Predict Dysglycemia in Children with Overweight and Obesity, Ages 8-18 Years.

Common dysglycemia measurements including fasting plasma glucose (FPG), oral glucose tolerance test (OGTT)-derived 2 h plasma glucose, and hemoglobin A1c (HbA1c) have limitations for children. Dynamic OGTT glucose and insulin responses may better reflect underlying physiology. This analysis assessed glucose and insulin curve shapes utilizing classifications-biphasic, monophasic, or monotonically increasing-and functional principal components (FPCs) to predict future dysglycemia. The prospective cohort included 671 participants with no previous diabetes diagnosis (BMI percentile ≥ 85th, 8-18 years old); 193 returned for follow-up (median 14.5 months). Blood was collected every 30 min during the 2 h OGTT. Functional data analysis was performed on curves summarizing glucose and insulin responses. FPCs described variation in curve height (FPC1), time of peak (FPC2), and oscillation (FPC3). At baseline, both glucose and insulin FPC1 were significantly correlated with BMI percentile (Spearman correlation r = 0.22 and 0.48), triglycerides (r = 0.30 and 0.39), and HbA1c (r = 0.25 and 0.17). In longitudinal logistic regression analyses, glucose and insulin FPCs predicted future dysglycemia (AUC = 0.80) better than shape classifications (AUC = 0.69), HbA1c (AUC = 0.72), or FPG (AUC = 0.50). Further research should evaluate the utility of FPCs to predict metabolic diseases.

The first International Association of Diabetes and Pregnancy Study Groups summit on the diagnosis of gestational diabetes in early pregnancy: TOBOGM Summit Report.

The first International Association of Diabetes and Pregnancy Study Groups Summit on the diagnosis of gestational diabetes in early pregnancy (Treatment of Booking Gestational Diabetes Mellitus (TOBOGM) Summit) was held on the 17 November 2022 in Sydney, Australia. It sought to use the TOBOGM trial findings to scope the issues involved with early screening, to inform future discussions over possible approaches for diagnosing gestational diabetes mellitus (GDM) in early pregnancy. Most delegates supported testing for early GDM using a one-step 75 g oral glucose tolerance test approach with Canadian Diabetes Association criteria preferred, but highlighted the importance of considering resources, cost, consumer perspectives and equity in translating TOBOGM results into a clinical approach to screening for, and diagnosing, early GDM.

Neonatal outcomes according to different glucose threshold values in gestational diabetes: a register-based study.

BACKGROUND: Mild hyperglycaemia is associated with increased birth weight but association with other neonatal outcomes is controversial. We aimed to study neonatal outcomes in untreated mild hyperglycaemia using different oral glucose tolerance test (OGTT) thresholds. METHODS: This register-based study included all (n = 4,939) singleton pregnant women participating a 75 g 2-h OGTT in six delivery hospitals in Finland in 2009. Finnish diagnostic cut-offs for GDM were fasting ≥ 5.3, 1 h ≥ 10.0 or 2-h glucose ≥ 8.6 mmol/L. Women who did not meet these criteria but met the International Association of the Diabetes and Pregnancy Study Groups (IADPSG) criteria (fasting 5.1-5.2 mmol/L and/or 2-h glucose 8.5 mmol/L, n = 509) or the National Institute for Health and Clinical Excellence (NICE) criteria (2-h glucose 7.8-8.5 mmol/L, n = 166) were considered as mild untreated hyperglycaemia. Women who met both the Finnish criteria and the IADPSG or the NICE criteria were considered as treated GDM groups (n = 1292 and n = 612, respectively). Controls were normoglycaemic according to all criteria (fasting glucose < 5.1 mmol/L, 1-h glucose < 10.0 mmol/L and 2-h glucose < 8.5 mmol/L, n = 3031). Untreated mild hyperglycemia groups were compared to controls and treated GDM groups. The primary outcome - a composite of adverse neonatal outcomes, including neonatal hypoglycaemia, hyperbilirubinaemia, birth trauma or perinatal mortality - was analysed using multivariate logistic regression. RESULTS: The risk for the adverse neonatal outcome in untreated mild hyperglycemia was not increased compared to controls (adjusted odds ratio [aOR]: 1.01, 95% confidence interval [CI]: 0.71-1.44, using the IADPSG criteria; aOR: 1.05, 95% CI: 0.60-1.85, using the NICE criteria). The risk was lower compared to the treated IADPSG (aOR 0.38, 95% CI 0.27-0.53) or the treated NICE group (aOR 0.32, 95% CI 0.18-0.57). DISCUSSION: The risk of adverse neonatal outcomes was not increased in mild untreated hyperglycaemia compared to normoglycaemic controls and was lower than in the treated GDM groups. The OGTT cut-offs of 5.3 mmol/L at fasting and 8.6 mmol/L at 2 h seem to sufficiently identify clinically relevant GDM, without excluding neonates with a risk of adverse outcomes.

Clinical and Metabolic Characterization of Women With Gestational Diabetes Mellitus Within the First Year Postpartum.

Context: Women with gestational diabetes mellitus (GDM) have an increased risk of long-term complications, including impaired glucose metabolism, type 2 diabetes (T2DM), cardiovascular disease, and obesity. In current clinical practice, a 1 size fits all approach to GDM is applied, although heterogeneity among women with GDM has been recognized. Objective: To give the most adequate preventive care and postpartum (PP) guidance, we aimed to make a metabolic characterization and identify subgroups of women with previous GDM within the first year PP. Methods: In this prospective cohort study, we collected data in gestational week 34-38, at 3 months, and 1 year PP on women with GDM who participated in a PP follow-up program in Central Region Denmark from April 2019 to December 2022. Results: In total, 1270 women were included in the program in late pregnancy. Of the 768 women participating in either the oral glucose tolerance test 3 months PP (n = 545) or the 1-year follow-up (n = 493) or both (n = 261), 608 (79.2%) were normoglycemic, 137 (17.8%) had prediabetes, 20 (2.6%) had T2DM, and 3 (.4%) had developed T1DM. More than 40% of the women gained weight in the first year PP compared with their pregestational weight. Conclusion: Our study shows that 20.8% of women with GDM who volunteered to participate in a clinical follow-up program developed prediabetes or diabetes (T1DM and T2DM) within the first year PP. The GDM diagnosis encompasses a heterogenetic group of women and a deeper characterization may provide an opportunity for a more personalized risk assessment to prevent the progression to T2DM.

Reframing prediabetes: A call for better risk stratification and intervention.

Prediabetes is an intermediate state of glucose homeostasis whereby plasma glucose concentrations are above normal but below the threshold of diagnosis for diabetes. Over the last several decades, criteria for prediabetes have changed as the cut points for normal glucose concentration and diagnosis of diabetes have shifted. Global consensus does not exist for prediabetes criteria; as a result, the clinical course and risk for type 2 diabetes vary. At present, we can identify individuals with prediabetes based on three glycemic tests (hemoglobin A1c, fasting plasma glucose, and 2-h plasma glucose during an oral glucose tolerance test). The majority of individuals diagnosed with prediabetes meet only one of these criteria. Meeting one, two, or all glycemic criteria changes risk for type 2 diabetes, but this information is not widely known and does not currently guide intervention strategies for individuals with prediabetes. This review summarizes current epidemiology, prognosis, and intervention strategies for individuals diagnosed with prediabetes and suggests a call for more precise risk stratification of individuals with prediabetes as elevated (one prediabetes criterion), high risk (two prediabetes criteria), and very high risk (three prediabetes criteria). In addition, the roles of oral glucose tolerance testing and continuous glucose monitoring in the diagnostic criteria for prediabetes need reassessment. Finally, we must reframe our goals for prediabetes and prioritize intensive interventions for those at high and very high risk for type 2 diabetes.

Metabolic Syndrome Prevalence in Women with Gestational Diabetes Mellitus in the Second Trimester of Gravidity.

Background: Women with gestational diabetes (GDM) have an increased risk of metabolic syndrome (MS) after delivery. MS could precede gravidity. The aims of this study were (i) to detect the prevalence of MS in women at the time of GDM diagnosis, (ii) to detect the prevalence of MS in the subgroup of GDM patients with any form of impaired glucose tolerance after delivery (PGI), and (iii) to determine whether GDM women with MS have a higher risk of peripartal adverse outcomes. Methods: A cross-sectional observational study comprised n = 455 women with GDM. International Diabetes Federation (IDF) criteria for MS definition were modified to the pregnancy situation. Results: MS was detected in 22.6% of GDM patients in those with PGI 40%. The presence of MS in GDM patients was associated with two peripartal outcomes: higher incidence of pathologic Apgar score and macrosomia (p = 0.01 resp. p = 0.0004, chi-square). Conclusions: The presence of MS in GDM patients is a statistically significant risk factor (p = 0.04 chi-square) for PGI. A strong clinical implication of our findings might be to include MS diagnostics within GDM screening using modified MS criteria in the second trimester of pregnancy.

Metabolic-Associated Fatty Liver Disease is Characterized by a Post-Oral Glucose Load Hyperinsulinemia in Individuals with Mild Metabolic Alterations.

Metabolic-associated fatty liver disease (MAFLD) has been identified as risk factor of incident type 2 diabetes (T2D), but the underlying postprandial mechanisms remains unclear. We compared the glucose metabolism, insulin resistance, insulin secretion and insulin clearance post-oral glucose tolerance test (OGTT) between individuals with and without MAFLD. We included 50 individuals with a BMI between 25-40 kg/m2 and ≥1 metabolic alteration: increased fasting triglycerides or insulin, plasma glucose 5.5-6.9 mmol/L, or glycated hemoglobin 5.7-5.9%. Participants were grouped according to MAFLD status, defined as hepatic fat fraction (HFF) ≥5% on MRI. We used oral minimal model on a frequently sampled 3h 75g-OGTT to estimate insulin sensitivity, insulin secretion, and pancreatic ß-cell function. Fifty percents of participants had MAFLD. Median age (IQR) (57 (45-65) vs 57 (44-63) years) and gender (60% vs 56% female) were comparable between groups. Post-OGTT glucose concentrations did not differ between groups, whereas post-OGTT insulin concentrations were higher in the MAFLD group (p <0.03). Individuals with MAFLD exhibited lower insulin clearance, insulin sensitivity and first phase pancreatic ß cell function. In all individuals, increased insulin incremental area under the curve and decreased insulin clearance were associated with HFF after adjusting for age, sex, and BMI (p <0.02). Amongst individuals with metabolic alterations, the presence of MAFLD was characterized mainly by post-OGTT hyperinsulinemia and reduced insulin clearance, while exhibiting lower first phase ß-cell function and insulin sensitivity. This suggests that MAFLD is linked with impaired insulin metabolism that may precede type 2 diabetes.

The WHO 2013 oral glucose tolerance test: The utility of isolated glucose measurements - A retrospective cohort study.

OBJECTIVE: The WHO 2013 guidelines recommend screening for gestational diabetes mellitus (GDM) by 3-point oral glucose tolerance test (OGTT). The objective of this retrospective cohort study was to evaluate GDM diagnosed by an isolated high glucose. STUDY DESIGN: We included pregnant women deemed at risk for GDM were offered GDM screening. We examined the records of 1939 consecutively screened pregnancies at two teaching hospitals in Amsterdam during 2016-2020. Using the WHO 2013 diagnostic criteria, we calculated the proportion of GDM cases diagnosed by isolated abnormal glucose values. RESULTS: Among those screened in our high risk cohort, GDM incidence was 31.5%. Of the GDM diagnoses, 57.0% were based on an isolated fasting glucose value, 30.9% based on multiple raised glucose measurements, 7.4% on an isolated raised 2-hour glucose and 4.7% on an isolated raised 1-hour glucose. For 1-hour glucose, the number needed to screen was 67 persons for one additional GDM case. CONCLUSION: The 1-hour glucose in the 3 point OGTT, as suggested by the WHO 2013 guidelines for GDM, contributes only small numbers of GDM cases and a high number needed to screen (67 for 1 additional case in a selective high risk GDM screening strategy), and is likely even less effective in universally screened populations.

Serum osteoglycin is stable during various glycemic challenges in healthy men.

PURPOSE: Osteoglycin is hypothesized to be metabolically active and may enhance insulin action. We hypothesized that osteoglycin levels increase during hyperglycemia as a physiological response to enhance the effects of insulin. METHODS: Eight healthy males were included in a cross-over study consisting of three study days following an 8 h fast. First, we performed an oral glucose tolerance test (OGTT); second, an isoglycemic intravenous glucose infusion (IIGI); and third, a control period consisting of a three hour fast. We analyzed blood samples for circulating osteoglycin levels during the study days. Repeated measures ANOVA was performed to compare levels of s-osteoglycin between OGTT, IIGI, and the fasting control. RESULTS: There were no differences in baseline osteoglycin levels among study days (p > 0.05). We observed no significant changes neither in absolute s-osteoglycin levels by time (p = 0.14) nor over time by study day (p = 0.99). Likewise, we observed no significant changes in percentage s-osteoglycin levels neither by time (p = 0.11) nor over time by study day (p = 0.89). CONCLUSION: We found that s-osteoglycin levels were stable for three hours during OGTT, IIGI, and fasting in healthy males. Based on the present study, circulating s-osteoglycin levels may be measured independently of fasting or non-fasting conditions. Furthermore, circulating physiological levels of glucose and insulin did not affect s-osteoglycin levels.

High-intensity interval training combining rowing and cycling improves but does not restore beta-cell function in type 2 diabetes.

Aim: We investigated whether a high-intensity interval training (HIIT) protocol could restore beta-cell function in type 2 diabetes compared with sedentary obese and lean individuals. Materials and methods: In patients with type 2 diabetes, and age-matched, glucose-tolerant obese and lean controls, we examined the effect of 8 weeks of supervised HIIT combining rowing and cycling on the acute (first-phase) and second-phase insulin responses, beta-cell function adjusted for insulin sensitivity (disposition index), and serum free fatty acid (FFA) levels using the Botnia clamp (1-h IVGTT followed by 3-h hyperinsulinemic-euglycemic clamp). Results: At baseline, patients with type 2 diabetes had reduced insulin sensitivity (~40%), acute insulin secretion (~13-fold), and disposition index (>35-fold), whereas insulin-suppressed serum FFA was higher (⁓2.5-fold) compared with controls (all P < 0.05). The HIIT protocol increased insulin sensitivity in all groups (all P < 0.01). In patients with type 2 diabetes, this was accompanied by a large (>200%) but variable improvement in the disposition index (P < 0.05). Whereas insulin sensitivity improved to the degree seen in controls at baseline, the disposition index remained markedly lower in patients with type 2 diabetes after HIIT (all P < 0.001). In controls, HIIT increased the disposition index by ~20-30% (all P < 0.05). In all groups, the second-phase insulin responses and insulin-suppressed FFA levels were reduced in response to HIIT (all P < 0.05). No group differences were seen in these HIIT-induced responses. Conclusion: HIIT combining rowing and cycling induced a large but variable increase in beta-cell function adjusted for insulin sensitivity in type 2 diabetes, but the disposition index remained severely impaired compared to controls, suggesting that this defect is less reversible in response to exercise training than insulin resistance. Trial registration: ClinicalTrials.gov (NCT03500016).

Early onset of abnormal glucose tolerance in patients with cystic fibrosis: A systematic review and meta-analysis.

BACKGROUND: Despite translational evidences suggesting that cystic fibrosis-related abnormal glucose tolerance (CF-related AGT) may begin early in life and is known to be associated with increased morbidity and mortality, current guidelines recommend screening for AGT only from 10 years of age, thus missing the opportunity for early detection and intervention. METHODS: A systematic review and meta-analysis (PROSPERO number: CRD42021282516) was conducted on studies that reported data on the prevalence of AGT or its subtypes in CF populations. Pooled proportions, risk, and odds ratios with 95 % confidence intervals (CI) were calculated. One-stage dose-response random-effect meta-analysis was used to assess the effect of age on CF-related diabetes (CFRD). RESULTS: The quantitative analysis included 457 studies and data from 520,544 patients. Every third child with CF (chwCF) (0.31 [95 % CI 0.25-0.37]) and every second adult with CF (awCF) (0.51 [95 % CI 0.45-0.57]) were affected by AGT. Even in the 5-10 years of age subgroup, the proportion of AGT was 0.42 [95 % CI 0.34-0.51]. The prevalence of prediabetes remained unchanged (impaired glucose tolerance in chwCF:0.14 [95 % CI 0.10-0.18]) vs. awCF:0.19 [95 % CI 0.14-0.25]), whereas the proportion of CFRD increased with age (0-5: 0.005 [95 % CI 0.0001-0.15]; 5-10: 0.05 [95 % CI 0.01-0.27]; 10-18: 0.11 [95 % CI 0.08-0.14]; >18 years of age: 0.27 [95 % CI 0.24-0.30]). CONCLUSION: CF-related AGT is common under 10 years of age. Our study suggests considering earlier AGT screening, starting from 5 years of age. This highlights the imperative for additional research for guideline adjustments and provides the opportunity for early intervention.

Does the combination of four OGTT values enhance the prediction of adverse pregnancy outcomes? Insights from a retrospective cohort study.

AIM: To explore the correlation between a singular value of additive OGTT scores and adverse maternal and neonatal outcomes. We postulated that a higher additive OGTT score would predict poorer maternal and neonatal outcomes. METHODS: In this retrospective cohort study, data were collected from all women with a documented complete OGTT result and subsequent diagnosis of GDM. The additive OGTT score was calculated by adding each individual hourly glucose measurement. Maternal demographics, pregnancy and labor characteristics, and neonatal outcomes were compared between the lower-sum and higher-sum OGTT groups. A multivariate regression analysis was performed to identify confounders associated with adverse outcomes. RESULTS: In this study, a total of 1497 patients were assessed. The group with higher-sum OGTT scores was characterized by increased rates of GDMA2 (p = 0.008), higher insulin doses (p = 0.009), and higher rates of composite maternal and neonatal adverse outcomes (p = 0.021 and p = 0.030, respectively) compared to the lower-sum OGTT group. CONCLUSION: The additive OGTT score may aid in predicting the need for insulin treatment, labor course, and neonatal outcomes in GDM patients.

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

AIMS: To investigate differences in maternal and foetal outcomes in pregnancy, where patients developed hypoglycaemia following the 2-hour 75g oral glucose tolerance test (OGTT). METHOD: A retrospective cohort study of 200 pregnancies attending the Antenatal Clinic at Tameside General Hospital between 2018 and 2022. Outcomes were compared between 4 groups: normal OGTT [G1; (n = 39, 20%), diagnosis of gestational diabetes mellitus (GDM) based on OGTT [G2; BG ≥ 5.6 mmol/L or 2-h OGTT ≥7.8 (n = 41, 21%)], hypoglycaemia [G3; 2 h OGTT 3.0-3.9 mmol/L (n = 93, 47%)], or clinically significant hypoglycaemia [G4; 2 h OGTT <3.0 mmol/L (n = 27, 14%)]. Maternal BMI, foetal birth weight (FBW), neonatal complications, neo-natal intensive care unit (NICU) stay and conversion to GDM were assessed. RESULTS: Maternal BMI was lower in G3 and G4 (27.3 kg/m2 and 28.1 kg/m2 respectively) compared to G1 (30.4 kg/m2) (p = 0.02). NICU stay was more frequent in G3 (12%, n = 11) and G4 (8%, n = 2) compared to G1 (5%, n = 2). Foetal complications occurred in 27% of G3 (n = 25) and 33% of G4 (n = 9) compared to 23% in G1 (n = 9) and 17% in G2 (n = 7). FBW was similar in G1 when compared to G3 and G4 (p = 0.34). Of the 120 patients in G3 and G4, 25 patients self-monitored blood glucose for two weeks; 28% (n = 7) subsequently developed GDM. CONCLUSION: Higher rates of NICU stay and foetal complications were seen in both hypoglycaemic groups. In patients with hypoglycaemia following OGTT there is evidence to support self-monitoring blood glucose as 28% were later diagnosed with GDM.

Clinical utility of point-of-care glucose testing in the assessment of gestational diabetes: Prospective cohort study.

OBJECTIVE: To assess the clinical utility of point-of-care (POC) capillary blood glucose (CBG) testing in the assessment of gestational diabetes mellitus (GDM) during oral glucose tolerance test (OGTT). DESIGN: Prospective cohort study. SETTING: Antenatal clinics at King's College Hospital. POPULATION: Women screened for GDM between March and June 2020. METHODS: The CBG was measured using the POC StatStrip® test and the venous plasma glucose (VPG) was measured by Roche analyser (Cobas 8000 c702). GDM was diagnosed based on the 2015 National Institute for Health and Clinical Excellence (NICE) Clinical Guideline criteria. The two methods were compared statistically using Analyse-It 5.40.2. MAIN OUTCOME MEASURES: Diagnostic sensitivity, specificity, positive and negative predictive values (PPV and NPV) for the POC StatStrip® test, compared with VPG measured by reference laboratory method. RESULTS: A total of 230 women were included. The number and percentage of women with glucose concentrations above the GDM threshold using the POC StatStrip® test versus laboratory VPG measurement was 15 (6.5%) versus eight (3.4%) at fasting and 105 (45.6%) versus 72 (31.1%) at 2 h, respectively. The sensitivity and specificity values (and 95% CIs) for the POC StatStrip® test were 88% (52%-99%) and 97% (93%-98%) at fasting and 97% (91%-99%) and 79% (71%-84%) at 2 h, respectively. However, the specificity and the NPV for the POC StatStrip® test for concentrations of ≤5.0 mmol/L at fasting or <7.5 mmol/L at 2 h were 100%, and the sensitivity and the PPV for concentrations of >9.5 mmol/L at 2 h were 100%. CONCLUSIONS: In our cohort the POC measurement of CBG cannot entirely replace the laboratory method for the OGTT; however, it can be used to rule out/rule in GDM for glucose concentrations of ≤5.0 mmol/L at fasting or <7.5/>9.5 mmol/L at 2 h.

Diagnostic accuracy of oral glucose tolerance tests, fasting plasma glucose and haemoglobin A1c for type 2 diabetes in women with polycystic ovary syndrome: A systematic review and meta-analysis.

AIMS: To inform international guidelines, a systematic review and meta-analysis was conducted to assess the performance of diagnostic methods for type 2 diabetes in women with polycystic ovary syndrome (PCOS). METHODS: An updated systematic search was conducted on five databases from 2017 until October 2023 and combined with prior searches (from inception). Meta-analyses of diagnostic accuracy tests were conducted. RESULTS: Nine studies comprising 2628 women with PCOS were included. Against the oral glucose tolerance test, a haemoglobin A1C (HbA1c) ≥ 6.5% had a pooled sensitivity of 50.00% (95% confidence interval (CI): 35.53-64.47), specificity of 99.86% (95%CI: 99.49-99.98), and positive and negative predictive values of 92.59% (95%CI: 75.27-98.09) and 98.27% (95%CI: 97.73-98.68), respectively, with an accuracy of 98.17% (95%CI: 97.34-98.79). Fasting plasma glucose values ≥ 7.0 mmol/L had a pooled sensitivity of 58.14% (95%CI: 42.13-72.99), specificity of 92.59% (95%CI: 75.35-98.08), positive and negative predictive values of 92.59% (95%CI: 75.35-98.08) and 99.09% (95%CI: 98.71-99.36), respectively, and an accuracy of 99.00% (95%CI: 98.46-99.39) against the oral glucose tolerance test. CONCLUSIONS: To our knowledge, this is the first systematic review assessing the performance of diagnostic methods for type 2 diabetes in women with PCOS. We demonstrate that using a cut-off for HbA1c of ≥6.5% in this population may result in misdiagnosis of half of the women with type 2 diabetes. Our results directly informed the recommendations of the 2023 International PCOS Guideline, suggesting that the oral glucose tolerance test is the optimal method for screening and diagnosing type 2 diabetes in women with PCOS and is superior to fasting plasma glucose and HbA1c.