Elevated 1 h postload plasma glucose levels identify adults with normal glucose tolerance but increased risk of non-alcoholic fatty liver disease

International Diabetes Federation Position Statement on the 1-hour post-load plasma glucose for the diagnosis of intermediate hyperglycaemia and type 2 diabetes

Many individuals with intermediate hyperglycaemia (IH), including impaired fasting glycaemia (IFG) and impaired glucose tolerance (IGT), as presently defined, will progress to type 2 diabetes (T2D). There is confirmatory evidence that T2D can be prevented by lifestyle modification and/or medications, in people with IGT diagnosed by 2-h plasma glucose (PG) during a 75-gram oral glucose tolerance test (OGTT). Over the last 40 years, a wealth of epidemiological data has confirmed the superior value of 1-h plasma glucose (PG) over fasting PG (FPG), glycated haemoglobin (HbA1c) and 2-h PG in populations of different ethnicity, sex and age in predicting diabetes and associated complications including death. Given the relentlessly rising prevalence of diabetes, a more sensitive, practical method is needed to detect people with IH and T2D for early prevention or treatment in the often lengthy trajectory to T2D and its complications. The International Diabetes Federation (IDF) Position Statement reviews findings that the 1-h post-load PG ≥ 155 mg/dL (8.6 mmol/L) in people with normal glucose tolerance (NGT) during an OGTT is highly predictive for detecting progression to T2D, micro- and macrovascular complications, obstructive sleep apnoea, cystic fibrosis-related diabetes mellitus, metabolic dysfunction-associated steatotic liver disease, and mortality in individuals with risk factors. The 1-h PG of 209 mg/dL (11.6 mmol/L) is also diagnostic of T2D. Importantly, the 1-h PG cut points for diagnosing IH and T2D can be detected earlier than the recommended 2-h PG thresholds. Taken together, the 1-h PG provides an opportunity to avoid misclassification of glycaemic status if FPG or HbA1c alone are used. The 1-h PG also allows early detection of high-risk people for intervention to prevent progression to T2D which will benefit the sizeable and growing population of individuals at increased risk of T2D. Using a 1-h OGTT, subsequent to screening with a non-laboratory diabetes risk tool, and intervening early will favourably impact the global diabetes epidemic. Health services should consider developing a policy for screening for IH based on local human and technical resources. People with a 1-h PG ≥ 155 mg/dL (8.6 mmol/L) are considered to have IH and should be prescribed lifestyle intervention and referred to a diabetes prevention program. People with a 1-h PG ≥ 209 mg/dL (11.6 mmol/L) are considered to have T2D and should have a repeat test to confirm the diagnosis of T2D and then referred for further evaluation and treatment. The substantive data presented in the Position Statement provides strong evidence for redefining current diagnostic criteria for IH and T2D by adding the 1-h PG.

One-hour post-load glucose levels are associated with hepatic steatosis assessed by transient elastography

AIM

To examine the association between 1-hour plasma glucose (PG) concentration and markers of non-alcoholic fatty liver disease (NAFLD) assessed by transient elastography (TE).

METHODS

We performed TE in 107 metabolically well-characterized non-diabetic White individuals. Controlled attenuation parameter (CAP) was used to quantify liver steatosis, while liver stiffness marker (LS) was used to evaluate fibrosis.

RESULTS

Controlled attenuation parameter correlated significantly with 1-hour PG (r = 0.301, P < 0.01), fasting insulin (r = 0.285, P < 0.01), 2-hour insulin (r = 0.257, P < 0.02), homeostasis model assessment index of insulin resistance (r = 0.252, P < 0.01), high-density lipoprotein cholesterol (r = -0.252, P < 0.02), body mass index (BMI; r = 0.248, P < 0.02) and age (r = 0.212, P < 0.03), after correction for age, sex and BMI. In a multivariable linear regression analysis, 1-hour PG (β = 0.274, P = 0.008) and fasting insulin levels (β = 0.225, P = 0.029) were found to be independent predictors of CAP. After excluding subjects with prediabetes, 1-hour PG was the sole predictor of CAP variation (β = 0.442, P < 0.001). In a logistic regression model, we observed that the group with 1-hour PG ≥  8.6 mmol/L (155 mg/dL) had a significantly higher risk of steatosis (odds ratio 3.98, 95% confidence interval 1.43-11.13; P = 0.008) than individuals with 1-hour PG <  8.6 mmol/L, after correction for potential confounders. No association was observed between 1-hour PG and LS.

CONCLUSION

Our data confirm that 1-hour PG ≥  8.6 mmol/L is associated with higher signs of NAFLD, even among individuals with normal glucose tolerance, categorized as low risk by canonical diagnostic standards. TE is a safe low-impact approach that could be employed for stratifying the risk profile in these patients, with a high level of accuracy.

The Triglycerides and Glucose (TyG) Index Is Associated with 1-Hour Glucose Levels during an OGTT

BACKGROUND AND OBJECTIVES

Among individuals with normal glucose tolerance (NGT), subjects with high levels of plasma glucose (≥155 mg/dL) at sixty minutes during an oral glucose tolerance test (1h-OGTT) are at an increased risk of developing type 2 diabetes. We investigated the association between the triglycerides and glucose (TyG) index, a novel marker of insulin resistance, with 1h-OGTT glucose plasma concentrations.

MATERIAL AND METHODS

1474 non-diabetic Caucasian subjects underwent a 75 g OGTT and were divided into two groups according to the cutoff 1h-OGTT plasma glucose < 155 mg/dL (NGT-1h-low) and ≥ 155 mg/dL (NGT-1h-high). The TyG index was calculated as ln [fasting triglycerides (milligrams per deciliter) × fasting blood glucose (milligrams per deciliter)/2]. Multivariable linear and logistic regression analyses were used to establish the contribution of the TyG index to the variability of 1h-OGTT glucose, and how the former affected the risk of being NGT-1h-high.

RESULTS

1004 individuals were NGT-1h-low and 470 were NGT-1h-high. The TyG index was higher for NGT-1h-high (p = 0.001) individuals, and it was an independent factor influencing 1h-OGTT glycemia (β = 0.191, p < 0.001) after correcting for age, sex, and BMI. The TyG index was the strongest marker associated with the risk of being NGT-1h-high (OR = 1.703, CI 95% 1.34-2.17, p < 0.001) when compared with FPG (OR = 1.054, CI 95% 1.04-1.07, p < 0.001) and the HOMA-IR (OR = 1.156, CI 95% 1.08-1.23, p < 0.001).

CONCLUSIONS

Our study demonstrated that the TyG index, an efficient and cost-effective marker of insulin resistance, is associated with the variability of early post-challenge glucose levels and is an independent marker of being NGT-1h-high.

Sex-specific differences in prevalence of nonalcoholic fatty liver disease in subjects with prediabetes and type 2 diabetes

AIMS

To characterize the prevalence of NAFLD among subjects with NGT, prediabetes and type 2 diabetes (T2DM) by sex in adults with one or more cardio-metabolic risk factors, and to assess whether cardio-metabolic factors explained sex-related differences in NAFLD prevalence.

METHODS

The study sample encompasses 742 individuals with NGT, 553 with prediabetes, and 431 with T2DM.

RESULTS

Women with prediabetes and T2DM exhibited greater relative differences in waist circumference, HOMA-IR, hsCRP, and lipid profile than prediabetic and diabetic men when compared with their NGT counterparts. Formal tests for glucose tolerance status × sex interaction were statistically significant for waist circumference (P = 0.008), HOMA-IR (P = 0.03), total cholesterol (P = 0.003), LDL (P = 0.001), HDL (P = 0.006), triglycerides (P < 0.0001), and hsCRP (P < 0.05). In a logistic regression analysis, prediabetic and diabetic women exhibited a higher OR for NAFLD than their male counterparts with test for glucose tolerance status × sex interaction being statistically significant.

CONCLUSIONS

Prediabetic and diabetic women have higher OR of having NAFLD than men. Deterioration of glucose homeostasis in women is associated with a greater worsening in metabolic risk factors than men, which may explain the stronger impact of prediabetes and T2DM on NAFLD in women.

Elevated One-Hour Post-Load Glucose Is Independently Associated with Albuminuria: A Cross-Sectional Population Study

The purpose of this study was to examine and compare the associations between albuminuria and fasting (FPG), 1 h post-load (1 h PG) and 2 h post-load plasma glucose (2 h PG) in an oral glucose tolerance test (OGTT). A total of 496 people free of known diabetes (mean age 72 years) participated in the examinations including the OGTT with plasma glucose measurements at 0, 1, and 2 h and levels of HbA1c. Albuminuria was determined by the urinary albumin-to-creatinine ratio and was defined as ≥3.0 mg/mmol. Compared with those without albuminuria, participants with albuminuria had significantly higher 1 h PG and 2 h PG levels, but not FPG or HbA1c levels. An elevated 1 h PG increased the estimated odds ratio of albuminuria more than three times in people with prediabetic 1 h PG (8.6–11.5 mmol/L: OR 3.60; 95% CI 1.70–7.64) and diabetic 1 h PG (≥11.6 mmol/L: OR 3.05; 95% CI 1.29–7.23). After adjusting for blood pressure and age, the association of elevated 1 h PG with albuminuria remained significant. Prediabetic or diabetic FPG, 2 h PG, or HbA1c did not have a statistically significant association with albuminuria. These findings suggest that 1 h PG seems to be the best glycemic parameter and is useful in recognizing persons with an elevated risk of early kidney disease due to hyperglycemia.

One-hour post-load glucose is associated with severity of hepatic fibrosis risk

AIM

Individuals with high 1-hour post-load glucose (1-h PG > 155 mg/dl; 8.6 mmol/l) during an oral glucose tolerance test are at increased risk of type 2 diabetes (T2D) and cardiovascular complications, hepatic steatosis, and mortality. However,the clinical relevance of 1-h PG for the severity of hepatic fibrosis risk remains undefined.

METHODS

Cross-sectional data of the CATAMERI study (n = 2335) were analyzed. Participants underwent anthropometric measurements, liver enzyme determinations, cardiometabolic profiling, and a75-gram oral glucose tolerance test, including fasting, 1-h and 2-h PG determinations and measurement of FIB-4 score to assess degree of hepatic fibrosis. Multivariable logistic regression analysis was performed to evaluate risk of advanced hepatic fibrosis with worsening glycemic status.

RESULTS

We stratifiedthe study group into 6 categories based on glycemic status: normal glucose tolerance (NGT) 1h-PG Low, NGT 1h-PG High, iIFG 1h-PG Low, iIFG 1h-PG High, IGT, and newly detected T2D. Anthropometric and cardiometabolic profiles worsened gradually with glycemic status. Moreover, compared to NGT-1h-PG Low group, worsening glycemic status was significantly associated with the severity of fibrosis, independent of other significant clinical risk factors.

CONCLUSIONS

1-PG is a valuable tool for stratifying subjects with NGT or IFG at heightened risk of hepatic fibrosis requiring further evaluation with elastography.

Augmented duodenal levels of sodium/glucose co-transporter 1 are associated with higher risk of nonalcoholic fatty liver disease and noninvasive index of liver fibrosis

AIMS

Subjects with elevated 1 h post-load glucose concentrations (1hPG) exhibit increased risk of non-alcoholic fatty liver disease (NAFLD) and duodenal sodium/glucose co-transporter 1 (SGLT-1) levels. Herein, we evaluate whether higher SGLT-1 duodenal levels are associated with NAFLD and increased risk of advance liver fibrosis.

METHODS

SGLT-1 levels were assessed on duodenal mucosa in 52 individuals subdivided into two groups according to ultrasonography-defined presence of NAFLD. Intracellular triglycerides levels and activation of endoplasmic reticulum (ER) stress were evaluated in human hepatocytes exposed to high-glucose concentration (HG).

RESULTS

Individuals with NAFLD exhibited higher duodenal SGLT-1 abundance along with raised 1hPG, as compared to those without NAFLD. The mediation analysis showed that augmented duodenal SGLT-1 levels were a predictor of NAFLD, and the link between increased duodenal SGLT-1 content and NAFLD risk was mediated by augmented 1hPG. Amongst participants with NAFLD, those with intermediate/high probability of advance liver fibrosis, estimated by NAFLD fibrosis score, exhibited higher duodenal SGLT-1 abundance and 1hPG levels as compared to the low probability group. Hepatocytes exposed to HG showed increased triglycerides accumulation and an up-regulation of ER stress pathway.

CONCLUSIONS

Increased duodenal SGLT-1 abundance and the related early post-prandial hyperglycemia are associated with NAFLD and advance liver fibrosis.

One-Hour Postload Plasma Glucose in Obese Indian Adults with Nonalcoholic Fatty Liver Disease: An Observational Study from North India

BACKGROUND

Metabolic perturbations and hyperglycemia are increasingly identified as causal factors for nonalcoholic fatty liver disease (NAFLD). Insulin resistance, an indirect marker for initiation of NAFLD can be promptly diagnosed with standard oral glucose tolerance test (OGTT). One-hour postOGTT plasma glucose measurement can have a significant impact on early identification of dysglycemia with NAFLD and may be superior to fasting and 2-hour plasma glucose.

OBJECTIVE

To assess 1-hour post OGTT plasma glucose levels and presence of NAFLD in obese adults.

MATERIALS AND METHODS

In this observational study, we included 101 consecutive obese (body mass index >25 kg/m²) participants of age 20-50 years without known illness of diabetes mellitus. Their anthropometric and laboratory characteristics were recorded and a standard OGTT was performed. Plasma glucose (PG) levels were measured during fasting, 1-hour (1-hour-PPG), and 2-hour (2-hour-PPG) intervals. All participants underwent ultrasound of the abdomen by a single, experienced observer for fatty liver (FL) grade assessment. Comparison of the PG and FL was done by the Chi-square test and a P value <0.05 was considered statistically significant with a 95% confidence interval. Data analysis was done using SPSS version 24.0 (IBM^® SPSS Statistics Inc., Chicago, Illinois, USA).

RESULTS

The result demonstrated that 53 adults had 1-hour-PPG values above the cutoff (≥155 mg/dl), whereas only 20 individuals had raised PG at 2 hours (≥140 mg/dl). All study subjects (100%) had an evidence of FL disease on ultrasound scan. Among these, 33 had grade I and 68 participants had grade II or III FL. About 41.6% of individuals had deranged 1-hour-PPG levels and higher FL grades as compared to 11.9% individuals with raised 2-hour-PPG values and FL of same grades. The relationship between 1-hour-PPG and FL grades was also statistically significant (P value <0.05).

CONCLUSIONS

1-hour-PPG levels were more deranged in obese adults without diabetes, and had more consistent and significant relationship with higher FL grades than the 2-hour-PPG levels.

Non-Laboratory-Based Simple Screening Model for Nonalcoholic Fatty Liver Disease in Patients with Type 2 Diabetes Developed Using Multi-Center Cohorts

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent cause of chronic liver disease worldwide. Type 2 diabetes mellitus (T2DM) is a risk factor that accelerates NAFLD progression, leading to fibrosis and cirrhosis. Thus, here we aimed to develop a simple model to predict the presence of NAFLD based on clinical parameters of patients with T2DM.

METHODS

A total of 698 patients with T2DM who visited five medical centers were included. NAFLD was evaluated using transient elastography. Univariate logistic regression analyses were performed to identify potential contributors to NAFLD, followed by multivariable logistic regression analyses to create the final prediction model for NAFLD.

RESULTS

Two NAFLD prediction models were developed, with and without serum biomarker use. The non-laboratory model comprised six variables: age, sex, waist circumference, body mass index (BMI), dyslipidemia, and smoking status. For a cutoff value of ≥60, the prediction accuracy was 0.780 (95% confidence interval [CI], 0.743 to 0.817). The second comprehensive model showed an improved discrimination ability of up to 0.815 (95% CI, 0.782 to 0.847) and comprised seven variables: age, sex, waist circumference, BMI, glycated hemoglobin, triglyceride, and alanine aminotransferase to aspartate aminotransferase ratio. Our non-laboratory model showed non-inferiority in the prediction of NAFLD versus previously established models, including serum parameters.

CONCLUSION

The new models are simple and user-friendly screening methods that can identify individuals with T2DM who are at high-risk for NAFLD. Additional studies are warranted to validate these new models as useful predictive tools for NAFLD in clinical practice.

CA.ME.LI.A. An epidemiological study on the prevalence of CArdiovascular, MEtabolic, LIver and Autoimmune diseases in Northern Italy

BACKGROUND AND AIMS

CA.ME.LI.A (CArdiovascular risks, MEtabolic syndrome, LIver and Autoimmune disease) is a cross-sectional, epidemiological study performed between 2009-2011 in Abbiategrasso (Milan, Italy) to estimate the prevalence of cardiovascular risk factors, metabolic syndrome, liver and autoimmune diseases in the general adult population. This report focuses on the description and presentation of baseline characteristics of the population.

METHODS AND RESULTS

Citizens were randomly selected from the city electoral registers (n = 30903), yielding a sample of 2554 subjects (M = 1257, F = 1297; age, 47 ± 15 yrs; range 18-77 yrs). Men had higher prevalence of overweight or obesity (60.8% vs 41.6%; p < 0.0001) and greater thickness of visceral adipose tissue (40 ± 19 vs 27 ± 17 mm; p < 0.0001); no gender difference was found in subcutaneous adipose tissue thickness. Men also showed higher levels of serum triglycerides, γ-GT, fasting blood glucose, insulin and Homa-IR Index, while HDL, CRP, and prevalence of elevated (>5.0 mg/L) CRP were lower. Compared to normal weight men, risk-ratio (RR) of CRP elevation was 1.32 (ns) in overweight and 2.68 (p < 0.0001) in obese subjects. The corresponding figures in females were 2.68 (p < 0.0001) and 5.18 (p < 0.0001). Metabolic syndrome was more frequent in men (32.7% vs 14.5%; RR: 2.24, p < 0.0001). Interadventitia common carotid artery diameter was higher in men and increased with age and BMI.

CONCLUSIONS

The present study reports on the overall characteristics of a large population from Northern Italy. It aims to identify the associations among cardiovascular risk factors to prevent their development and progression, improve healthy lifestyle and identify subjects liable to pharmacological interventions.

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.

Evaluation of the relationship between the one-hour plasma glucose concentration and beta-cell functions and cardiometabolic parameters during oral glucose tolerance test in obese children and adolescents

Background In this study, we aimed to evaluate the relationship between the 1-h plasma glucose (PG) level in the oral glucose tolerance test (OGTT) and conventional glycemic parameters, indices evaluating beta-cell functions, and cardiometabolic risk factors. Methods The records of 532 obese patients who were followed up in the Pediatric Endocrinology Polyclinic and who underwent standard OGTT were evaluated retrospectively. All patients were divided into two groups according to OGTT data as the 1-h plasma glucose concentration <155 mg/dL (n=329) and ≥155 mg/dL (n=203). Patients with normal glucose tolerance (NGT) were divided into two groups according to the 1-h PG level, as 218 patients with NGT 1 h-low (<155 mg/dL) and 53 patients with high NGT 1 h-high (≥155 mg/dL). Results There was a statistically significant difference between the lipid profiles of individuals with NGT 1 h-low (<155 mg/dL) and individuals with NGT 1 h-high (≥155 mg/dL) (p<0.001). Total cholesterol, LDL cholesterol, and triglyceride levels were higher, while HDL cholesterol levels were lower in individuals with NGT 1 h-high (≥155 mg/dL). The indices evaluating beta-cell functions were significantly higher in individuals with NGT 1 h-low (<155 mg/dL). Conclusion As a result, a plasma glucose concentration above or equal to 155 mg/dL at 1 h during an OGTT is associated with a worse clinical phenotype characterized by changes in insulin sensitivity and β-cell function. Therefore, this threshold value can predict the progression of prediabetes in obese young people with NGT.

Elevated 1-h post-load plasma glucose levels in normal glucose tolerance children with obesity is associated with early carotid atherosclerosis

CONTEXT

Evidence suggests that the 1-h post-load plasma glucose (1-h PG) ≥155mg/dL during an oral glucose tolerance test (OGTT) predicts development of type 2 diabetes (T2DM) and associated complications, among adults with normal glucose tolerance (NGT), but relevant data on children is scarce.

OBJECTIVES

To investigate whether NGT children with obesity whose 1-h PG is ≥155mg/dL have an increased carotid intima-media thickness (IMT) and exhibit non-alcoholic fatty liver disease (NAFLD) diagnosed by ultrasonography, as compared with NGT subjects with 1-h PG <155mg/dL and impaired glucose tolerance (IGT).

METHODS

Cardio-metabolic profile, OGTT, measurements of carotid IMT and liver ultrasonography were analyzed in 171 non-diabetic children with obesity. Subjects were divided into 3 groups: NGT subjects with a 1-h PG <155mg/dL, NGT subjects with a 1-h PG ≥155mg/dL, and IGT subjects.

RESULTS

As compared with NGT individuals with a 1-h PG <155mg/dL, NGT individuals with a 1-h PG ≥155mg/dL exhibited higher carotid IMT (0.75±0.15mm vs. 0.68±0.15mm; p<0.05). No significant differences were observed in carotid IMT between IGT and NGT subjects with a 1-h PG ≥155mg/dL (0.75±0.18mm vs 0.75±0.15mm; p>0.05). Of the three glycemic parameters, 1-h and 2-h PG, but not fasting glucose, were significantly correlated with carotid IMT. There were no significant differences for increased risk of having NAFLD between the three groups.

CONCLUSIONS

These data suggest that a value of 1-h PG ≥155mg/dL in children and adolescents with obesity is as important as IGT with respect to cardiovascular risks.

Elevated 1-h postload plasma glucose levels identify coronary heart disease patients with greater severity of coronary artery lesions and higher risk of 1-year re-admission

OBJECTIVE

To investigate the relationship of 1-h postload plasma glucose during the oral glucose tolerance test with the severity of coronary artery lesions and risk of 1-year re-admission in coronary heart disease patients with normal glucose tolerance.

METHODS

A total of 266 consecutive coronary heart disease patients who underwent coronary angiography and had normal glucose tolerance confirmed by oral glucose tolerance test during hospitalization were prospectively enrolled and followed in two groups according to the 1-h postload plasma glucose cut-off point (1-h postload plasma glucose <155 mg/dL, n = 149 and 1-h postload plasma glucose ⩾155 mg/dL, n = 117). Angiographic severity was assessed by number of diseased vessels, lesion morphology and Gensini score. The risk of 1-year re-admission with adverse cardiovascular events after discharge was analysed.

RESULTS

Subjects with a 1-h postload plasma glucose ⩾155 mg/dL had higher incidence of multivessel disease and complex lesions, Gensini score and risk of 1-year re-admission than subjects with a 1-h postload plasma glucose <155 mg/dL (all p < 0.05). In the stepwise multivariate regression analysis, 1-h postload plasma glucose was the major determinant of the Gensini score. Subgroup analyses by sex showed that men with a 1-h postload plasma glucose ⩾155 mg/dL had higher incidence of complex lesions and risk of 1-year re-admission than men with a 1-h postload plasma glucose <155 mg/dL (all p < 0.05).

CONCLUSION

Coronary heart disease patients with normal glucose tolerance and elevated 1-h postload plasma glucose levels had a greater severity of coronary artery lesions and an increased risk of re-admission with adverse cardiovascular events, particularly in men.

1-Hour Post-OGTT Glucose Improves the Early Prediction of Type 2 Diabetes by Clinical and Metabolic Markers

CONTEXT

Early prediction of dysglycemia is crucial to prevent progression to type 2 diabetes. The 1-hour postload plasma glucose (PG) is reported to be a better predictor of dysglycemia than fasting plasma glucose (FPG), 2-hour PG, or glycated hemoglobin (HbA1c).

OBJECTIVE

To evaluate the predictive performance of clinical markers, metabolites, HbA1c, and PG and serum insulin (INS) levels during a 75-g oral glucose tolerance test (OGTT).

DESIGN AND SETTING

We measured PG and INS levels at 0, 30, 60, and 120 minutes during an OGTT in 543 participants in the Botnia Prospective Study, 146 of whom progressed to type 2 diabetes within a 10-year follow-up period. Using combinations of variables, we evaluated 1527 predictive models for progression to type 2 diabetes.

RESULTS

The 1-hour PG outperformed every individual marker except 30-minute PG or mannose, whose predictive performances were lower but not significantly worse. HbA1c was inferior to 1-hour PG according to DeLong test P value but not false discovery rate. Combining the metabolic markers with PG measurements and HbA1c significantly improved the predictive models, and mannose was found to be a robust metabolic marker.

CONCLUSIONS

The 1-hour PG, alone or in combination with metabolic markers, is a robust predictor for determining the future risk of type 2 diabetes, outperforms the 2-hour PG, and is cheaper to measure than metabolites. Metabolites add to the predictive value of PG and HbA1c measurements. Shortening the standard 75-g OGTT to 1 hour improves its predictive value and clinical usability.

Petition to replace current OGTT criteria for diagnosing prediabetes with the 1-hour post-load plasma glucose ≥ 155 mg/dl (8.6 mmol/L)

Many individuals with prediabetes, as presently defined, will progress to diabetes (T2D) despite the considerable benefit of lifestyle modification. Therefore, it is paramount to screen individuals at increased risk with a more sensitive method capable of identifying prediabetes at an even earlier time point in the lengthy trajectory to T2D. This petition reviews findings demonstrating that the 1-hour (1-h) postload plasma glucose (PG) ≥ 155 mg/dl (8.6 mmol/L) in those with normal glucose tolerance (NGT) during an oral glucose tolerance test (OGTT) is highly predictive for detecting progression to T2D, micro- and macrovascular complications and mortality in individuals at increased risk. Furthermore, the STOP DIABETES Study documented effective interventions that reduce the future risk of T2D in those with NGT and a 1-h PG ≥ 155 mg/dl (8·6 mmol/L). The 1-h OGTT represents a valuable opportunity to extend the proven benefit of diabetes prevention to the sizeable and growing population of individuals at increased risk of progression to T2D. The substantial evidence provided in this petition strongly supports redefining current diagnostic criteria for prediabetes with the elevated 1-h PG level. The authors therefore advocate a 1-h OGTT to detect prediabetes and hence, thwart the global diabetes epidemic.

One-Hour Postload Hyperglycemia: Implications for Prediction and Prevention of Type 2 Diabetes

CONTEXT

Recently, a value of 1-hour postload glucose concentration (1-h-PG) ≥155 mg/dL (8.6 mmol/L) in individuals with normal glucose tolerance (NGT) has been found to be associated with an increased risk for future type 2 diabetes mellitus (T2DM). In this review, we analyze the implication of 1-h-PG determination in prediction of T2DM and cardiovascular disease.

DESIGN

A literature search was performed using MEDLINE. We included all English studies published up to February 2018 in peer-reviewed journals that examined the relationship between 1-h-PG and diabetes, cardiometabolic alterations, organ damage, and cardiovascular disease.

RESULTS

Several longitudinal studies have consistently shown that 1-h-PG ≥155 mg/dL can recognize individuals at increased risk for future T2DM among subjects with NGT. Additionally, we describe the pathophysiological abnormalities associated with 1-h-PG ≥155 mg/dL including impaired insulin sensitivity, β-cell dysfunction, and increased glucose intestinal absorption, which are known to be involved in T2DM pathogenesis. Importantly, numerous studies have demonstrated that a value of 1-h-PG ≥155 mg/dL in individuals with NGT is not only linked to an increased risk for future T2DM, but also able to identify those having a worse cardiovascular phenotype and an increased risk of adverse cardiovascular outcomes.

CONCLUSIONS

Although 1-h-PG determination is not currently recommended by the American Diabetes Association for identifying high-risk individuals, the available evidence indicates that a value of 1-h-PG ≥155 mg/dL may be a useful tool to recognize, among subjects with NGT, those at increased risk of T2DM and cardiovascular disease.

Lessons learned from the 1-hour post-load glucose level during OGTT: Current screening recommendations for dysglycaemia should be revised

This perspective covers a novel area of research describing the inadequacies of current approaches for diagnosing dysglycaemia and proposes that the 1-hour post-load glucose level during the 75-g oral glucose tolerance test may serve as a novel biomarker to detect dysglycaemia earlier than currently recommended screening criteria for glucose disorders. Considerable evidence suggests that a 1-hour post-load plasma glucose value ≥155 mg/dl (8.6 mmol/L) may identify individuals with reduced β-cell function prior to progressing to prediabetes and diabetes and is highly predictive of those likely to progress to diabetes more than the HbA_1c or 2-hour post-load glucose values. An elevated 1-hour post-load glucose level was a better predictor of type 2 diabetes than isolated 2-hour post-load levels in Indian, Japanese, and Israeli and Nordic populations. Furthermore, epidemiological studies have shown that a 1-hour PG ≥155 mg/dl (8.6 mmol/L) predicted progression to diabetes as well as increased risk for microvascular disease and mortality when the 2-hour level was <140 mg/dl (7.8 mmol/L). The risk of myocardial infarction or fatal ischemic heart disease was also greater among subjects with elevated 1-hour glucose levels as were risks of retinopathy and peripheral vascular complications in a Swedish cohort. The authors believe that the considerable evidence base supports redefining current screening and diagnostic recommendations with the 1-hour post-load level. Measurement of the 1-hour PG level would increase the likelihood of identifying a larger, high-risk group with the additional practical advantage of potentially replacing the conventional 2-hour oral glucose tolerance test making it more acceptable in a clinical setting.

The 1-h post-load plasma glucose as a novel biomarker for diagnosing dysglycemia

Identifying the earliest moment for intervention to avert progression to prediabetes and diabetes in high-risk individuals is a substantial challenge. As β-cell function is already compromised in prediabetes, attention should therefore be focused on identifying high-risk individuals earlier in the so-called pre-prediabetes stage. Biomarkers to monitor progression and identify the time point at which β-cell dysfunction occurs are therefore critically needed. Large-scale population studies have consistently shown that the 1-h plasma glucose (1-h PG) ≥ 155 mg/dl (8.6 mmol/l) during the oral glucose tolerance test detected incident type 2 diabetes and associated complications earlier than fasting plasma glucose or 2-h plasma glucose levels. An elevated 1-h PG level appears to be a better alternative to HbA1c [5.7-6.4% (37-47 mmol/mol)] or traditional glucose criteria for identifying high-risk individuals at a stage when ß-cell function is substantially more intact than in prediabetes. Diagnosing high-risk individuals earlier proffers the opportunity for potentially reducing progression to diabetes, development of microvascular complications and mortality, thereby advancing benefit beyond that which has been demonstrated in global diabetes prevention programs.

The influence of prehypertension, hypertension, and glycated hemoglobin on the development of type 2 diabetes mellitus in prediabetes: the Korean Genome and Epidemiology Study (KoGES)

BACKGROUND

It has been reported that elevated blood pressure (BP) was significantly associated with the increased risk for type 2 diabetes mellitus (T2DM). However, there is still limited information about the influence of BP on the risk for T2DM across the level of glycated hemoglobin (HbA1c).

METHOD

In a cohort of the Korean Genome and Epidemiology Study (KoGES), 2830 non-diabetic Korean adults with prediabetes defined by HbA1c level of 5.7-6.4% were followed-up for 10 years. Multivariate cox proportional hazards assumption was used to assess the risk for T2DM according to the baseline BP categories (normal, prehypertension and hypertension) and HbA1c level (low: 5.7-5.9% and high: 6.0-6.4%).

RESULTS

The risk for T2DM significantly increased proportionally to BP categories (adjusted HR; reference in normal BP, 1.32 [1.10-1.59] in prehypertension and 1.61 [1.35-1.92] in hypertension). Subgroup analysis indicated that individuals with high HbA1c had the higher risk for T2DM than individuals with low HbA1c regardless of BP. Additionally, combined presence of hypertension and high HbA1c had the highest risk for T2DM (adjusted HR: 3.82 [3.00-4.87]). In each systolic and diastolic BP level, the risk for T2DM significantly increased from systolic BP ≥ 130 mmHg (adjusted HRs: 1.39 ([1.15-1.71]) and diastolic BP ≥ 80 mmHg (adjusted HRs: 1.30 ([1.07-1.58]).

CONCLUSION

BP and HbA1c may be useful tools in identifying individuals with prediabetes more potentially predisposed to T2DM. Prospective studies should be considered to examine whether controlling BP actually lowers the risk for T2DM.

One-hour post-load plasma glucose levels associated with decreased insulin sensitivity and secretion and early makers of cardiometabolic risk

PURPOSE

Obese adults with normal glucose tolerance (NGT) but with 1-hour post-load plasma glucose (1hPG) ≥ 155 mg/dl are at higher risk of developing type 2 diabetes (T2D) and cardiometabolic complications. Little information is available for the pediatric population, where recently, a lower cutoff, 132.5 mg/dl, has been suggested as being more sensitive to identify subjects at risk of T2D. Our aim was to assess whether obese Caucasian youth with 1hPG ≥ 132.5 mg/dl have worse insulin sensitivity and secretion and a worse cardiometabolic profile compared to obese youth with 1hPG < 132.5 mg/dl.

METHODS

Medical records of 244 (43% male; age: 11.1 ± 2.7years) overweight/obese children and adolescents, who had undergone an oral glucose tolerance test (OGTT), were retrieved. Anthropometric and biochemical data were collected from the hard copy archive. Indexes of insulin resistance (HOMA-IR), insulin sensitivity (WBISI), and insulin secretion (Insulinogenic Index, Disposition Index) were calculated.

RESULTS

Of the 244 records analyzed, 215 fulfilled criteria for NGT and had complete biochemical data. Among NGT patients, 42 (19.5%) showed 1hPG ≥ 132.5 mg/dL (high-NGT), while the remaining had 1hPG < 132.5 mg/dL (low-NGT). The high-NGT group showed a higher male prevalence (59.5 vs 37%), lower Disposition Index (0.54 [0.39-0.71] vs 0.79 [0.47-1.43]), and WBISI (0.24 [0.18-0.35] vs 0.33 [0.23-0.50]) than the low-NGT group. High-NGT subjects also showed a trend towards lower HDL-cholesterol and higher triglycerides/HDL-cholesterol ratio (2.13 [1.49-3.41] vs 1.66 [1.24-2.49]).

CONCLUSIONS

In overweight/obese NGT Caucasian youth a 1hPG ≥ 132.5 mg/dL was able to identify those with impaired insulin sensitivity and secretion and a trend towards a worse cardio-metabolic profile, a group likely at risk for future T2D.

Reducing the prevalence of dysglycemia: is the time ripe to test the effectiveness of intervention in high-risk individuals with elevated 1 h post-load glucose levels?

Identifying the earliest time point on the prediabetic continuum is critical to avoid progressive deterioration in β-cell function. Progressively rising glucose levels even within the "normal range" occur considerably late in the evolution to diabetes thus presenting an important opportunity for earlier diagnosis, treatment, and possible reversal. An elevated 1 h postprandial glucose level, not detected by current diagnostic standards, may provide an opportunity for the early identification of those at risk. When the 1 h post-load glucose level is elevated, lifestyle intervention may have the greatest benefit for preserving β-cell function and prevent further progression to prediabetes and diabetes. In view of the considerable consistent epidemiologic data in large disparate populations supporting the predictive capacity of the1 h post-load value for predicting progression to diabetes and mortality, the time is therefore ripe to evaluate this hypothesis in a large, prospective multicenter randomized trial with lifestyle intervention.

The risk of transient postprandial oxyhypoglycemia in nonalcoholic fatty liver disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is frequently associated with insulin resistance (IR) and abnormalities in glucose metabolism. Prevalent postprandial hyperinsulinemia along with insulin resistance in NAFLD may lead to hypoglycemia. This study investigated the prevalence of postprandial oxyhypoglycemia in patients with NAFLD.

METHODS

The oral glucose tolerance test (OGTT) with 75 g glucose was performed in 375 biopsy-proven NAFLD patients with prior unknown type 2 diabetes mellitus (DM). Serum glucose and insulin levels were measured for 3 h after glucose loading and the clinical parameters were compared.

RESULTS

Normal glucose tolerance (NGT), impaired glucose tolerance (IGT), and DM were observed in 36, 36, and 28 %, respectively. Hypoglycemia (≤70 mg/dL) after 3 h was observed in 14.4 % of all patients. The rate of hypoglycemia was significantly higher in NGT (63 % of NGT) than in IGT (30 % of IGT) and DM (7 % of DM) (P < 0.05). In patients with hypoglycemia, the levels of insulin were significantly higher at 30 and 60 min than those without hypoglycemia (P < 0.05). By multivariate analysis, high-LDL cholesterolemia (P < 0.05), low-HDL cholesterolemia (P < 0.05), and fibrosis (P < 0.05) were significant factors that contributed to hypoglycemia after 3 h on 75 g OGTT.

CONCLUSIONS

A relatively higher proportion of NAFLD cases exhibited transient postprandial hypoglycemia after 3 h on OGTT, especially in NAFLD patients with early-stage fibrosis. By performing 75 g OGTT for 3 h, hypoglycemia would be diagnosed earlier and the treatment intervention would decrease the progression of NAFLD and deterioration of glucose metabolism.

Adolescent gynecomastia is associated with a high incidence of obesity, dysglycemia, and family background of diabetes mellitus

BACKGROUND

Gynecomastia during adolescence is common though etiology is not clear. We studied the clinical and hormonal profile of adolescent patients with gynecomastia.

METHODOLOGY

Patients who had onset of breast development between age 10 and 20 years were included in this study. Their clinical profile, biochemical, and hormonal parameters were studied.

RESULTS

Of 94 patients with gynecomastia, 4 had hypogonadotropic hypogonadism, 4 had hypergonadotropic hypogonadism, and 1 had fibroadenosis, but in majority (90.4%), no apparent cause for breast enlargement was evident. In the idiopathic group, majority were obese (63%). Fourteen (16%) patients had impaired fasting glucose or impaired glucose tolerance. Another twenty patients had subtle abnormalities (high 1 h glucose or glucose peak at 2 h). Twenty-nine percent of lean and 38% of obese patients had mild abnormalities in glucose profile. Sixty percent of patients had family background of diabetes. Obese patients had lower testosterone as compared to lean patients; however, estradiol, luteinizing hormone, and follicle-stimulating hormone levels were similar in the two groups.

CONCLUSION

Gynecomastia during adolescence is associated with obesity, dysglycemia, and family background of diabetes mellitus.

One-hour post-load hyperglycemia combined with HbA1c identifies pre-diabetic individuals with a higher cardio-metabolic risk burden

BACKGROUND AND AIMS

Evidence suggests that combining 1-hour plasma glucose ≥155 mg/dl during an oral glucose tolerance test (OGTT) with glycosylated hemoglobin (HbA1c) significantly increases their predictive power for incident diabetes, while their individual and joint associations with cardio-metabolic risk factors remain undefined. Herein, we evaluated whether 1-hour post-load plasma glucose ≥155 mg/dl combined with HbA1c may identify pre-diabetic individuals with a higher cardio-metabolic risk.

METHODS

Anthropometric and metabolic characteristics, insulin sensitivity and insulin secretion assessed by OGTT-derived indexes, carotid intima-media thickness (IMT), pulse pressure, and rate pressure product were evaluated in 1495 individuals.

RESULTS

As compared with subjects with 1-hour post-load glucose <155 mg/dl, individuals with 1-hour post-load glucose ≥155 mg/dl exhibited a significantly worse cardio metabolic profile, both in the group with HbA1c <5.7%, and in the group with prediabetes (HbA1c 5.7-6.4%). Specifically, in both groups, subjects with 1-hour post-load glucose ≥155 mg/dl had higher fasting and 2-h post-load glucose (p < 0.0001 for all in both groups), higher HOMA-IR (p < 0.0001 in both groups), and carotid IMT (p = 0.05 in the group with HbA1c <5.7% and p = 0.03 in the group HbA1c 5.7-6.4%), as well as lower Matsuda index, insulinogenic index and disposition index (p < 0.0001 in both groups), and lower insulin-stimulated glucose disposal (p < 0.0001 in the group with HbA1c <5.7% and p = 0.03 in the group HbA1c 5.7-6.4%).

CONCLUSIONS

Hyperglycemia at 1-hour during an OGTT may be a useful tool to identify a subset of individuals within HbA1c-defined glycemic categories at higher risk of developing type 2 diabetes and cardiovascular disease.

The 1-hour post-load glucose level is more effective than HbA1c for screening dysglycemia

AIM

To assess the performance of HbA1c and the 1-h plasma glucose (PG ≥ 155 mg/dl; 8.6 mmol/l) in identifying dysglycemia based on the oral glucose tolerance test (OGTT) from a real-world clinical care setting.

METHODS

This was a diagnostic test accuracy study. For this analysis, we tested the HbA1c diagnostic criteria advocated by the American Diabetes Association (ADA 5.7-6.4 %) and International Expert Committee (IEC 6.0-6.4 %) against conventional OGTT criteria. We also tested the utility of 1-h PG ≥ mg/dl; 8.6 mmol/l. Prediabetes was defined according to ADA-OGTT guidelines. Spearman correlation tests were used to determine the relationships between HbA1c, 1-h PG with fasting, 2-h PG and indices of insulin sensitivity and β-cell function. The levels of agreement between diagnostic methods were ascertained using Cohen's kappa coefficient (Κ). Receiver operating characteristic (ROC) curve was used to analyze the performance of the HbA1c and 1-h PG test in identifying prediabetes considering OGTT as reference diagnostic criteria. The diagnostic properties of different HbA1c thresholds were contrasted by determining sensitivity, specificity and likelihood ratios (LR).

RESULTS

Of the 212 high-risk individuals, 70 (33 %) were identified with prediabetes, and 1-h PG showed a stronger association with 2-h PG, insulin sensitivity index, and β-cell function than HbA1c (P < 0.05). Furthermore, the level of agreement between 1-h PG ≥ 155 mg/dl (8.6 mmol/l) and the OGTT (Κ[95 % CI]: 0.40[0.28-0.53]) diagnostic test was stronger than that of ADA-HbA1c criteria 0.1[0.03-0.16] and IEC criteria (0.17[0.04-0.30]). The ROC (AUC[95 % CI]) for HbA1c and 1-h PG were 0.65[0.57-0.73] and 0.79[0.72-0.85], respectively. Importantly, 1-h PG ≥ 155 mg/dl (8.6 mmol/l) showed good sensitivity (74.3 % [62.4-84.0]) and specificity 69.7 % [61.5-77.1]) with a LR of 2.45. The ability of 1-h PG to discriminate prediabetes was better than that of HbA1c (∆AUC: -0.14; Z value: 2.5683; P = 0.01022).

CONCLUSION

In a real-world clinical practice setting, the 1-h PG ≥ 155 mg/dl (8.6 mmol/l) is superior for detecting high-risk individuals compared with HbA1c. Furthermore, HbA1c is a less precise correlate of insulin sensitivity and β-cell function than the 1-h PG and correlates poorly with the 2-h PG during the OGTT.

One-Hour Postload Hyperglycemia Is a Stronger Predictor of Type 2 Diabetes Than Impaired Fasting Glucose

CONTEXT

Subjects with normal glucose tolerance (NGT) but 1-h postload glucose ≥ 155 mg/dL (NGT-1h-high) exhibit an intermediate cardiometabolic risk profile between individuals with NGT and impaired glucose tolerance (IGT).

OBJECTIVE

This study aimed to evaluate whether NGT-1h-high subjects have different cardiometabolic characteristics and an increased risk of type 2 diabetes compared with individuals with isolated impaired fasting glucose (IFG).

SETTING, DESIGN, AND PATIENTS

A cross-sectional analysis was performed on 595 nondiabetic subjects who underwent an oral glucose tolerance test and an euglycemic hyperinsulinemic clamp in an ambulatory care setting. In addition, a longitudinal analysis was performed on 392 individuals, who were reexamined after a followup of 5.2 ± 0.9 y.

MAIN OUTCOME MEASURES

Insulin sensitivity, beta-cell function, and risk of developing diabetes were measured.

RESULTS

Subjects with NGT-1h-high have a significant reduction of peripheral insulin sensitivity and beta-cell function, assessed by the disposition index, compared with either 1-h postload glucose < 155 mg/dL (NGT-1h-low) or IFG individuals, but not compared with IGT. Among the 392 subjects studied in the longitudinal analysis the incidence rate of type 2 diabetes over the follow-up period was 2.9, 16.7, 12.5, and 31.4% for subjects with NGT-1h-low, NGT-1h-high, IFG, and IGT, respectively. In a Cox proportional hazard regression analysis the risk of developing diabetes for NGT-1h-high subjects was 4.02 (95% confidence interval [CI] 1.06-15.26); an even higher risk (6.67; 95% CI, 2.09-21.24) was observed in subjects with IGT, but not in the isolated IFG group (1.91; 95% CI, 0.44-8.29).

CONCLUSIONS

NGT-1h-high subjects exhibit a higher risk of developing diabetes than those with IFG or NGT-1h-low, likely due to decreased insulin sensitivity and beta-cell function.

Chronic cadmium exposure in rats produces pancreatic impairment and insulin resistance in multiple peripheral tissues

Previous studies have linked cadmium exposure to disturbances in carbohydrate and lipid metabolism. In this study we investigate the effects in Wistar rats of an oral cadmium exposure in drinking water on carbohydrates, lipids and insulin release. Also, using mathematical models we studied the effect of cadmium on insulin resistance and sensitivity in liver, muscle, adipose and cardiovascular tissue. Cadmium exposure induced hyperglycemia, increased insulin release after a glucose load, and caused increases in serum triglycerides, cholesterol, LDL-C and VLDL-C, and a decrease of HDL-C. In addition, there was an accumulation of cadmium in pancreas and an increase of insulin. After exposure, HOMA-IR was increased, while the HOMA-S%, QUICKI and Matsuda-DeFronzo indexes showed decreases. A decrease of insulin sensitivity was shown in muscle and liver. Additionally, cadmium increases insulin resistance in the liver, adipose tissue and cardiovascular system. Finally, β-cell functioning was evaluated by HOMA-B% index and insulin disposition index, which were decreased, while insulin generation index increased. In conclusion, cadmium increases insulin release, induces hyperglycemia and alters lipid metabolism. These changes likely occur as a consequence of reduced sensitivity and increased insulin resistance in multiple insulin-dependent and non-dependent tissues, producing a biochemical phenotype similar to metabolic syndrome and diabetes.