Low concordance between HbA1c and OGTT to diagnose prediabetes and diabetes in overweight or obesity

Real-world clinical validation of the Qatar pre-diabetes risk score: a cross-sectional study

Introduction

Pre-diabetes stands as a prominent, independent risk factor for the onset of type 2 diabetes (T2D), with 5%-10% of individuals with pre-diabetes progressing to T2D annually. The effectiveness of rigorous lifestyle interventions in averting the transition from pre-diabetes to T2D has been substantiated across multiple investigations and populations. Consequently, the clinical imperative of early pre-diabetes detection becomes unequivocal. This study assessed the validity of the recently developed pre-diabetes risk score in Qatar (PRISQ) in a real-world clinical setting.

Research design and methods

We recruited 1021 walk-in participants from 3 different health centres of Qatar's Primary Health Care Corporation. Only adult people without known pre-diabetes or diabetes were included in the study. Along with blood collected for the haemoglobin A1c (HbA1c) test to confirm pre-diabetes, we recorded the age, gender, weight, waist circumference, systolic and diastolic blood pressure, nationality, smoking state and family history of diabetes. Negative predictive value, positive predictive value, sensitivity and specificity of PRISQ were computed.

Results

Of the 1021 participants, 797 agreed to provide blood. HbA1c test revealed that 21.9% of the 797 subjects had pre-diabetes (HbA1c between 5.7% and 6.5%) while 3.3% had undiagnosed diabetes (HbA1c≥ 6.5%). Using a PRISQ cut-off of 16, PRISQ sensitivity exceeded 90% in all subgroups of individuals aged 40 years and above, regardless of ethnicity. We did not see any significant improvement in PRISQ sensitivity when we considered the family history of diabetes.

Conclusions

We confirmed a good PRISQ diagnostic rate for pre-diabetes from a representative sample of the Qatar population recruited in a real-world clinical setting. PRISQ can potentially play a significant role in curbing the T2D epidemic sweeping Qatar and beyond.

Abnormal Glucose Tolerance in Women Diagnosed With Gestational Diabetes (WHO 2013) 10 Years After Index Pregnancy

Context

It is not clear if the risk of abnormal glucose tolerance (AGT) is attenuated in the long-term in women diagnosed with gestational diabetes (GDM) using the World Health Organization (WHO) 2013 criteria and who have received appropriate treatment during pregnancy.

Objective

We aimed to assess the long-term prevalence of AGT and other cardiovascular disease (CVD) risk factors in this cohort.

Methods

A retrospective cohort follow-up study was conducted of 37 and 107 women diagnosed with and without GDM respectively using the WHO 2013 criteria between June 2010 and December 2010. Women were invited to attend our center, where they underwent a 75-g oral glucose tolerance test, blood and urine collection, body measurements, and electrocardiography. Main outcome measure included the development of AGT using the American Diabetes Association criteria.

Results

Sixteen (43.2%) women with GDM compared to 5 (4.7%) women with normal glucose tolerance (NGT) at index pregnancy had AGT (P < .001). In the GDM group, 10 (27.0%), 7 (18.9%), and 4 (10.8%) women had impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and type 2 diabetes mellitus (T2DM), respectively. In the NGT group, 2 (1.9%), 3 (2.8%), and 1 (0.9%) woman had IFG, IGT, and T2DM, respectively. Women with AGT also had an unfavorable metabolic profile including obesity, hypertension, insulin resistance, and dyslipidemia.

Conclusion

Women treated for GDM (WHO 2013 criteria) remain at increased risk for developing AGT and adverse CVD risk factors as early as a decade after diagnosis. Continued efforts are needed to accurately follow this population to address modifiable risk factors.

Preoperative glycated hemoglobin concentration and early postoperative infections in patients undergoing spinal surgery: A systematic review

Early postoperative infections can affect a significant number of spinal surgery patients. Many studies reported on the features that may associate with elevated risk of infectious complications in this group. Data on the impact of glucose metabolism disorders in this area are well known. At the same time information on the correlation of preoperative HbA1c level and postoperative infections in spinal surgery are still scarce. Furthermore there are no strict recommendations regarding routine HbA1c testing prior to elective surgery. In present SR we aimed to report available clinical evidence on association between preoperative HbA1c and early postoperative infections. We used PubMed and EMBASE database and a set of specific key words (spine surgery AND infections AND HbA1c) to identify eligible studies. The study was registered in PROSPERO database and reported according to PRISMA recommendations. 16 studies were selected for further assessment. Predominance of data indicated a significant correlation between preoperative HbA1c concentration and elevated risk of postoperative infections, as well as higher rate of non - infective complications and worse patients future outcome. Adequately designed future studies on purposely dimensioned sample size are needed to confirm the role of preoperative HbA1c testing in preoperative management of spinal surgery patients.

Optimal glycated hemoglobin A1c value for prediabetes and diabetes in patients with pancreatic diseases

BACKGROUND

Some articles suggest that using HbA1c alone for diabetes diagnosis is inappropriate. It requires considerable researches to explore the efficacy of HbA1c for diagnosing hyperglycemia in patients with pancreatic disease.

METHODS

This study analyzed 732 patients, comprising of 331 without pancreatic disease and 401 patients diagnosed with pancreatic diseases. All participants underwent the HbA1c assay and oral glucose tolerance test. Kappa coefficients were calculated to assess agreement between the HbA1c and glucose criteria. The receiver operating characteristic curve (ROC) was used to calculate the optimal HbA1c value. DeLong test was analyzed to compared the aera under curves (AUCs).

RESULTS

There were 203 (61.3%) patients with NGT, 78 (23.6%) with prediabetes, and 50 (15.1%) with diabetes in patients without pancreatic diseases. In patients with pancreatic disease, 106 participants were diagnosed with NGT (36.4%), 125 with prediabetes (31.2%), and 130 with diabetes (32.4%). Patients with pancreatic disease exhibited elevated levels of bilirubin, transaminase enzymes, aspartate transaminase, high density lipoprotein cholesterol and total bile acid. The sensitivity and specificity of the HbA1c (6.5%) for diagnosing pancreatic diabetes were 60.8% (95% CI 52.3, 69.3) and 92.6% (95% CI 89.5, 95.7). In prediabetes, the sensitivity and specificity of HbA1c (5.7%) is 53.2% (44.3, 62.0) and 59.6 (51.5, 67.6). The optimal HbA1c value for diagnosing diabetes was 6.0% (AUC = 0.876, 95% CI 0.839, 0.906), with the sensitivity of 83.8% and the specificity of 76.8%. The optimal HbA1c value for the diagnosis of prediabetes was 5.8% (AUC = 0.617, 95% CI: 0.556, 0.675), with the corresponding sensitivity and specificity of 48.0% and 72.6% respectively. The combined tests (HbA1c, 6.0% or FPG, 7.0mmol/L) presented the sensitivity of 85.7% (95% CI 79.1, 91.3)and the specificity of 92.6% (95% CI 87.6, 97.3) in pancreatic diabetes.

CONCLUSION

From our results, the recommended HbA1c by ADA criterion may not be sufficiently sensitive to diagnose hyperglycemia in pancreatic disease. The optimal value of 5.8% and 6.0% improved the accuracy for diagnosing prediabetes and diabetes and should be considered to be applied. Besides, we advocate the combination of HbA1c and FPG test for the diagnosis of diabetes in patients with pancreatic diseases.

Assessment of Type 2 Diabetes Risk in Young Women with Polycystic Ovary Syndrome

Women with polycystic ovary syndrome (PCOS) are at increased risk for dysglycemia and type 2 diabetes compared to healthy BMI-matched women of reproductive age: robust evidence exists supporting this notion. The presence of altered glycemic status in young women with the syndrome presents a distinct challenge for the clinician for several reasons. Firstly, the reported incidence of this disorder varies among the limited available studies. Furthermore, there is a lack of consensus on the best screening method, which women to screen, at what frequency, and which strategies need to be implemented to reduce the above risk. We provide data regarding the prevalence of dysglycemia in young women suffering from PCOS and the pathophysiological mechanisms underlying the disorder. In addition, we present evidence suggesting universal screening with the oral glucose tolerance test in young women with the syndrome, irrespective of age or BMI status, to identify and manage glycemic abnormalities in a timely manner. Regarding follow-up, oral glucose testing should be carried out at regular intervals if there are initial abnormal findings or predisposing factors. Finally, the efficacy of a well-balanced diet in conjunction with regular exercise and the use of non-pharmacologic agents in this specific population is discussed.

Does the Effect of a 3-Year Lifestyle Intervention on Body Weight and Cardiometabolic Health Differ by Prediabetes Metabolic Phenotype? A Post Hoc Analysis of the PREVIEW Study

OBJECTIVE

To examine whether the effect of a 3-year lifestyle intervention on body weight and cardiometabolic risk factors differs by prediabetes metabolic phenotype.

RESEARCH DESIGN AND METHODS

This post hoc analysis of the multicenter, randomized trial, PREVention of diabetes through lifestyle interventions and population studies In Europe and around the World (PREVIEW), included 1,510 participants with prediabetes (BMI ≥25 kg ⋅ m-2; defined using oral glucose tolerance tests). Of these, 58% had isolated impaired fasting glucose (iIFG), 6% had isolated impaired glucose tolerance (iIGT), and 36% had IFG+IGT; 73% had normal hemoglobin A1c (HbA1c; <39 mmol ⋅ mol-1) and 25% had intermediate HbA1c (39-47 mmol ⋅ mol-1). Participants underwent an 8-week diet-induced rapid weight loss, followed by a 148-week lifestyle-based weight maintenance intervention. Linear mixed models adjusted for intervention arm and other confounders were used.

RESULTS

In the available-case and complete-case analyses, participants with IFG+IGT had greater sustained weight loss after lifestyle intervention (adjusted mean at 156 weeks -3.5% [95% CI, -4.7%, -2.3%]) than those with iIFG (mean -2.5% [-3.6%, -1.3%]) relative to baseline (P = 0.011). Participants with IFG+IGT and iIFG had similar cardiometabolic benefits from the lifestyle intervention. The differences in cardiometabolic benefits between those with iIGT and IFG+IGT were minor or inconsistent in different analyses. Participants with normal versus intermediate HbA1c had similar weight loss over 3 years and minor differences in cardiometabolic benefits during weight loss, whereas those with normal HbA1c had greater improvements in fasting glucose, 2-h glucose (adjusted between-group difference at 156 weeks -0.54 mmol ⋅ L-1 [95% CI -0.70, -0.39], P < 0.001), and triglycerides (difference -0.07 mmol ⋅ L-1 [-0.11, -0.03], P < 0.001) during the lifestyle intervention.

CONCLUSIONS

Individuals with iIFG and IFG+IGT had similar improvements in cardiometabolic health from a lifestyle intervention. Those with normal HbA1c had greater improvements than those with intermediate HbA1c.

Concordance between indirect fibrosis and steatosis indices and their predictors in subjects with overweight/obesity

BACKGROUND

The non-invasive assessment of steatosis/fibrosis tried to overcome some of peri-procedural risk of liver biopsy; for this, several indices of steatosis and fibrosis in liver have been proposed.

AIM

To evaluate concordance of non-invasive fibrosis and steatosis indices in a large population of adult subjects at risk of NAFLD, and how obesity and its physio-pathological features may interact with steatosis/fibrosis indexes and related biomarkers of cardio-metabolic risk.

METHODS

Indices of steatosis (fatty liver index-FLI), NAFLD liver fat score-NLFS)) and fibrosis (Fibrosis 4 (FIB-4), BARD, BAAT and FORN) were calculated in 1145 outpatients with overweight or obesity at risk for T2D and NAFLD. Indices were correlated with clinical variables.

RESULTS

Concordance between tests occurred in 81% of the overall values between FLI and NLFS, but was lower when comparing the other fibrosis scores (FIB-4 vs FORN 72%, FIB-4 vs BARD 36%, BARD vs FORN 46%, BARD vs BAAT 58%, FIB-4 vs BAAT 46%, BAAT vs FORN 62%). Each index was differently correlated with anthropometric, clinical and laboratory variables.

CONCLUSION

Indices evaluated retain low concordance, clinicians should be aware of these differences between steatosis/fibrosis scores when expressing a differential liver disease diagnosis or assessing the progression of a known liver disease.

LEVEL OF EVIDENCE

Level V, descriptive research.

Oxidative Status and Thiol/Disulfide Homeostasis Are Changed During 75 g Oral Glucose Tolerance Test over a Five-Hour Period

BACKGROUND

Oral glucose loading may affect oxidative status during oral glucose tolerance test (OGTT). We aimed to investigate how oxidant and antioxidant markers and thiol/disulfide parameters change during OGTT.

METHODS

OGTT was performed to 42 volunteers who were considered risk of type 2 diabetes and were divided into three groups (normoglycemic, prediabetes, diabetes) according glucose levels during OGTT. Glucose, insulin, c-peptide, total antioxidant status (TAS), total oxidant status (TOS), total thiol and native thiol were investigated with auto-anaylzer for five-hours period.

RESULTS

Decrease of TAS and increase of TOS levels began with the increase in glucose and insulin levels. The increase of TAS started at third hour and reached the highest levels at fifth hour. OSI levels were higher at fourth hour than fasting and first hours in normoglycemic and diabetes groups. In the prediabetic group, TAS were higher than the other groups, TOS peak was at the second hour (p < 0.05). Native thiol and total thiol levels showed variable course during OGTT, both parameters increased at the end of the process (p < 0.05). Disulfide levels showed an increase trend but it was not statistically different in normoglycemic and diabetes groups. In prediabetes group, second hour disulfide level was lower than fasting state and disulfide was significantly increased at third, fourth and fifth hours and fifth hour disulfide level was also higher than fasting.

CONCLUSION

Oxidative stress parameters and thiol/disulfide balance were found to deteriorate within five-hours after glucose loading in all groups. These results indicates that oxidative stress occurs during OGTT.

Can dysglycemia in OGTT be predicted by baseline parameters in patients with PCOS?

Background

Polycystic ovary syndrome (PCOS) is considered a risk factor for the development of type 2 diabetes mellitus (T2DM). However, which is the most appropriate way to evaluate dysglycemia in women with PCOS and who are at increased risk are as yet unclear.

Aim of the study

To determine the prevalence of T2DM, impaired glucose tolerance (IGT), and impaired fasting glucose (IFG) in PCOS women and potential factors to identify those at risk.

Subjects and methods

The oral glucose tolerance test (OGTT), biochemical/hormonal profile, and ovarian ultrasound data from 1614 Caucasian women with PCOS and 362 controls were analyzed in this cross-sectional multicenter study. The data were categorized according to age and BMI.

Results

Dysglycemia (T2DM, IGT, and IFG according to World Health Organization criteria) was more frequent in the PCOS group compared to controls: 2.2% vs 0.8%, P = 0.04; 9.5% vs 7.4%, P = 0.038; 14.2% vs 9.1%, P = 0.002, respectively. OGTT was essential for T2DM diagnosis, since in 88% of them basal glucose values were inconclusive for diagnosis. The presence of either T2DM or IFG was irrespective of age (P = 0.54) and BMI (P = 0.32), although the latter was associated with IGT (P = 0.021). There was no impact of age and BMI status on the prevalence of T2DM or IFG. Regression analysis revealed a role for age, BMI, fat deposition, androgens, and insulin resistance for dysglycemia. However, none of the factors prevailed as a useful marker employed in clinical practice.

Conclusions

One-third of our cohort of PCOS women with either T2DM or IGT displayed normal fasting glucose values but without confirming any specific predictor for dysglycemic condition. Hence, the evaluation of glycemic status using OGTT in all women with PCOS is strongly supported.

Polycystic ovary syndrome and type 2 diabetes mellitus: A state-of-the-art review

Polycystic ovary syndrome (PCOS) often coexists with a wide spectrum of dysglycemic conditions, ranging from impaired glucose tolerance to type 2 diabetes mellitus (T2D), which occur to a greater extent compared to healthy body mass index-matched women. This concurrence of disorders is mainly attributed to common pathogenetic pathways linking the two entities, such as insulin resistance. However, due to methodological flaws in the available studies and the multifaceted nature of the syndrome, there has been substantial controversy as to the exact association between T2D and PCOS which has not yet been elucidated. The aim of this review is to present the best available evidence regarding the epidemiology of dysglycemia in PCOS, the unique pathophysiological mechanisms underlying the progression of dysglycemia, the most appropriate methods for assessing glycemic status and the risk factors for T2D development in this population, as well as T2D risk after transition to menopause. Proposals for application of a holistic approach to enable optimal management of T2D risk in PCOS are also provided. Specifically, adoption of a healthy lifestyle with adherence to improved dietary patterns, such the Mediterranean diet, avoidance of consumption of endocrine-disrupting foods and beverages, regular exercise, and the effect of certain medications, such as metformin and glucagon-like peptide 1 receptor agonists, are discussed. Furthermore, the maintenance of a healthy weight is highlighted as a key factor in achievement of a significant reduction of T2D risk in women with PCOS.

Long-term prognosis in patients with acute myocardial infarction and newly detected glucose abnormalities: predictive value of oral glucose tolerance test and HbA1c

BACKGROUND

Disturbances of glucose metabolism can be diagnosed by an oral glucose tolerance test (OGTT) and by glycated haemoglobin (HbA1c). The aim of this study was to investigate the association between newly detected disturbances of glucose metabolism and long-term prognosis after acute myocardial infarction (AMI) and to compare the predictive value of an OGTT and HbA1c.

METHODS

Patients under the age of 80 years with no known history of diabetes admitted for AMI at the Department of Cardiology, Danderyd University Hospital, Stockholm, Sweden, from January 1st, 2006 until December 31st, 2013, were investigated with an OGTT and a HbA1c before discharge and were classified as having normal glucose tolerance (NGT), prediabetes or diabetes according to American Diabetes Association (ADA) criteria. Using nationwide, all-inclusive registers, patients were followed for the incidence of combined event [CE (first of myocardial infarction, heart failure, ischaemic stroke or mortality)] for a mean follow-up time of 4.8 years. Cox regression analysis was used to calculate Hazard Ratios (HR) and their 95% confidence intervals (CI).

RESULTS

Of the 841 patients who were investigated with both an OGTT and a HbA1c, 139 (17%) patients had NGT, 398 (47%) had prediabetes and 304 (36%) had diabetes according to OGTT. The corresponding figures using HbA1c were 320 (38%), 461 (55%) and 60 (7%). Patients with newly discovered diabetes were older and had a higher body mass index compared to those with NGT. OGTT was not predictive for CE. In contrast, prediabetes identified by a HbA1c was associated with an increased risk for CE (HR 1.31; 95% CI 1.05-1.63) compared to normoglycaemia. When comparing the prognostic value of different glucose and HbA1c cut-offs, only a HbA1c ≥ 39 mmol/mol was significantly associated with CE (HR 95% CI; 1.30:1.05-1.61).

CONCLUSION

In this single-centre study, in a recent contemporary cohort, we found that around two thirds of the patients admitted with AMI with no known history of diabetes had disturbed glucose metabolism, in accordance with previous studies. HbA1c in the prediabetes range, but not OGTT, added predictive value on the long-term outcome, in a cohort to whom a pathologic OGTT result was communicated with lifestyle advice.

A Prediction Model Based on Noninvasive Indicators to Predict the 8-Year Incidence of Type 2 Diabetes in Patients with Nonalcoholic Fatty Liver Disease: A Population-Based Retrospective Cohort Study

Background

The prevention of type 2 diabetes (T2D) and its associated complications has become a major priority of global public health. In addition, there is growing evidence that nonalcoholic fatty liver disease (NAFLD) is associated with an increased risk of diabetes. Therefore, the purpose of this study was to develop and validate a nomogram based on independent predictors to better assess the 8-year risk of T2D in Japanese patients with NAFLD.

Methods

This is a historical cohort study from a collection of databases that included 2741 Japanese participants with NAFLD without T2D at baseline. All participants were randomized to a training cohort (n = 2058) and a validation cohort (n = 683). The data of the training cohort were analyzed using the least absolute shrinkage and selection operator method to screen the suitable and effective risk factors for Japanese patients with NAFLD. A cox regression analysis was applied to build a nomogram incorporating the selected features. The C-index, receiver operating characteristic curve (ROC), calibration plot, decision curve analysis, and Kaplan-Meier analysis were used to validate the discrimination, calibration, and clinical usefulness of the model. The results were reevaluated by internal validation in the validation cohort.

Results

We developed a simple nomogram that predicts the risk of T2D for Japanese patients with NAFLD by using the parameters of smoking status, waist circumference, hemoglobin A1c, and fasting blood glucose. For the prediction model, the C-index of training cohort and validation cohort was 0.839 (95% confidence interval (CI), 0.804-0.874) and 0.822 (95% CI, 0.777-0.868), respectively. The pooled area under the ROC of 8-year T2D risk in the training cohort and validation cohort was 0.811 and 0.805, respectively. The calibration curve indicated a good agreement between the probability predicted by the nomogram and the actual probability. The decision curve analysis demonstrated that the nomogram was clinically useful.

Conclusions

We developed and validated a nomogram for the 8-year risk of incident T2D among Japanese patients with NAFLD. Our nomogram can effectively predict the 8-year incidence of T2D in Japanese patients with NAFLD and helps to identify people at high risk of T2D early, thus contributing to effective prevention programs for T2D.

The Oral Glucose Tolerance Test: 100 Years Later

For over 100 years, the oral glucose tolerance test (OGTT) has been the cornerstone for detecting prediabetes and type 2 diabetes (T2DM). In recent decades, controversies have arisen identifying internationally acceptable cut points using fasting plasma glucose (FPG), 2-h post-load glucose (2-h PG), and/or HbA1c for defining intermediate hyperglycemia (prediabetes). Despite this, there has been a steadfast global consensus of the 2-h PG for defining dysglycemic states during the OGTT. This article reviews the history of the OGTT and recent advances in its application, including the glucose challenge test and mathematical modeling for determining the shape of the glucose curve. Pitfalls of the FPG, 2-h PG during the OGTT, and HbA1c are considered as well. Finally, the associations between the 30-minute and 1-hour plasma glucose (1-h PG) levels derived from the OGTT and incidence of diabetes and its complications will be reviewed. The considerable evidence base supports modifying current screening and diagnostic recommendations with the use of the 1-h PG. Measurement of the 1-h PG level could increase the likelihood of identifying high-risk individuals when the pancreatic ß-cell function is substantially more intact with the added practical advantage of potentially replacing the conventional 2-h OGTT making it more acceptable in the clinical setting.