Evaluation of nonfasting tests to screen for childhood and adolescent dysglycemia

Key influences on dysglycemia across Fujian's urban-rural divide

BACKGROUND

Screening and treatment of dysglycemia (prediabetes and diabetes) represent significant challenges in advancing the Healthy China initiative. Identifying the crucial factors contributing to dysglycemia in urban-rural areas is essential for the implementation of targeted, precise interventions.

METHODS

Data for 26,157 adults in Fujian Province, China, were collected using the Social Factors Special Survey Form through a multi-stage random sampling method, wherein 18 variables contributing to dysglycemia were analyzed with logistic regression and the random forest model.

OBJECTIVE

Investigating urban-rural differences and critical factors in dysglycemia prevalence in Fujian, China, with the simultaneous development of separate predictive models for urban and rural areas.

RESULT

The detection rate of dysglycemia among adults was 35.26%, with rates of 34.1% in urban areas and 35.8% in rural areas. Common factors influencing dysglycemia included education, age, BMI, hypertension, and dyslipidemia. For rural residents, higher income (OR = 0.80, 95% CI [0.74, 0.87]), average sleep quality (OR = 0.89, 95% CI [0.80, 0.99]), good sleep quality (OR = 0.89, 95% CI [0.80, 1.00]), and high physical activity (PA) (OR = 0.87, 95% CI [0.79, 0.96]) emerged as protective factors. Conversely, a daily sleep duration over 8 hours (OR = 1.46, 95% CI [1.03, 1.28]) and middle income (OR = 1.12, 95% CI [1.03, 1.22]) were specific risk factors. In urban areas, being male (OR = 1.14, 95% CI [1.02, 1.26]), cohabitation (OR = 1.18, 95% CI [1.02, 1.37]), and central obesity (OR = 1.35, 95% CI [1.19, 1.53]) were identified as unique risk factors. Using logistic regression outcomes, a random forest model was developed to predict dysglycemia, achieving accuracies of 75.35% (rural) and 76.95% (urban) with ROC areas of 0.77 (rural) and 0.75 (urban).

CONCLUSION

This study identifies key factors affecting dysglycemia in urban and rural Fujian residents, including common factors such as education, age, BMI, hypertension, and dyslipidemia. Notably, rural-specific protective factors are higher income and good sleep quality, while urban-specific risk factors include being male and central obesity. These findings support the development of targeted prevention and intervention strategies for dysglycemia, tailored to the unique characteristics of urban and rural populations.

High prevalence of impaired glucose metabolism among children and adolescents living with HIV in Ghana

BACKGROUND

Antiretroviral therapy (ART)-associated metabolic abnormalities, including impairment of glucose metabolism, are prevalent in adults living with HIV. However, the prevalence and pathogenesis of impaired glucose metabolism in children and adolescents living with HIV, particularly in sub-Saharan Africa, are not well characterized. We investigated the prevalence of impaired glucose metabolism among children and adolescents living with perinatally infected HIV in Ghana.

METHODS

In this multicentre, cross-sectional study, we recruited participants from 10 paediatric antiretroviral treatment clinics from January to June 2022 in 10 facilities in Greater Accra and Eastern regions of Ghana. We determined impaired glucose metabolism in the study sample by assessing fasting blood sugar (FBS), insulin resistance as defined by the homeostatic model assessment for insulin resistance (HOMA-IR) index and glycated haemoglobin (HbA1c) levels. The prevalence of impaired glucose metabolism using each criterion was stratified by age and sex. The phenotypic correlates of glucose metabolism markers were also assessed among age, sex, body mass index (BMI) and waist-to-hip ratio (WHR).

RESULTS

We analysed data from 393 children and adolescents living with HIV aged 6-18 years. A little over half (205/393 or 52.25%) of the children were female. The mean age of the participants was 11.60 years (SD = 3.50), with 122/393 (31.00%) aged 6-9 years, 207/393 (52.67%) aged 10-15 years, and 62/393 (15.78%) aged 16-18 years. The prevalence rates of glucose impairment in the study population were 15.52% [95% confidence interval (CI): 12.26-19.45], 22.39% (95% CI: 18.54-26.78), and 26.21% (95% CI: 22.10-30.78) using HbA1c, HOMA-IR, and FBS criteria, respectively. Impaired glucose metabolism detected by FBS and HOMA-IR was higher in the older age group, whereas the prevalence of abnormal HbA1c levels was highest among the youngest age group. Age and BMI were positively associated with FBS and HOMA-IR (p < 0.001). However, there was negative correlation of WHR with HOMA-IR (p < 0.01) and HbA1c (p = 0.01).

CONCLUSION

The high prevalence of impaired glucose metabolism observed among the children and adolescents living with HIV in sub-Saharan Africa is of concern as this could contribute to the development of metabolic syndrome in adulthood.

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.

Prevalence of prediabetes by the fasting plasma glucose and HbA1c screening criteria among the children and adolescents of Shenzhen, China

Background

Prediabetes is associated with an increased risk of cardiovascular diseases and all-cause mortality. Rare research in China has evaluated the prevalence of prediabetes among children and adolescents using the HbA1c criterion or the combined FPG-or-HbA1c diagnostic criterion, and researchers paid no attention to the distributions of blood glucose in Shenzhen, especially for juveniles.

Methods

We conducted a school-based cross-sectional study based on the first-year students from 17 primary, middle, and high schools. Prediabetes was defined as FPG of 5.6-6.9 mmol/L or HbA1c of 5.7%-6.4%. The crude and standardized prevalence of prediabetes with 95% confidence interval (95% CI) was estimated.

Results

A total of 7519 participants, aged 6 to 17 years, were included. For all subjects, the crude prevalence (95% CI) of prediabetes was 1.49% (1.21-1.77), 8.72% (8.08-9.36), and 9.80% (9.13-10.47) by the FPG-only, HbA1c-only, and FPG-or-HbA1c criteria, respectively. Based on the 2010 Shenzhen census population, the standardized prevalence was 1.56% (males 1.85%, females 1.19%), 11.05% (males 11.47%, females 10.53%), and 12.19% (males 13.01%, females 11.15%) by the corresponding criteria. The proportion of prediabetes was higher for males than females, and the prevalence decreased with grade for males but increased for females. The association of BMI and prediabetes was U-shaped curve, indicating higher rates of prediabetes for underweight and obesity people.

Conclusion

The blood glucose status of children and adolescents in Shenzhen is worrisome, and the early detection and management of prediabetes are imperative.

Risk Factors for Progression to Type 2 Diabetes in a Pediatric Prediabetes Clinic Population

Background

Pediatric type 2 diabetes (T2D) is increasing in prevalence, yet it is unclear what definition of pediatric prediabetes predicts progression to T2D. Strategies are needed to better identify at risk individuals who could benefit from early intervention.

Methods

Retrospective chart review of a pediatric prediabetes clinic over 7 years. Inclusion criteria include hemoglobin A1c (HbA1C) and ≥1 glucose from oral glucose tolerance test. Exclusion criteria include type 1 diabetes, maturity onset diabetes of the young, or T2D on initial visit.

Results

A total of 552 patients were included, 6.5% (n = 36) progressed to T2D over 2.4 ± 1.5 years. At initial visit, T2D progressors had a higher body mass index (38.6 ± 6.5 vs 34.2 ± 8.4 kg/m2, P = .002), HbA1C (6.0 ± 0.3%, vs 5.7± 0.3, P < .001), 2-hour glucose (141 ± 28 vs 114 ± 29 mg/dL, P < .001), and C-peptide (4.8 vs 3.6 ng/mL, P = .001). Fasting glucose was not significantly different. In a multivariable model, male sex (hazard ratio [HR], 2.4; P = .012), initial visit HbA1C (HR, 1.3 per 0.1% increase; P < .001), and 2-hour glucose level (HR, 1.2 per 10 mg/dL increase; P = .014) were all predictive of T2D progression. Patients who progressed to T2D had an increase in body mass index of 4.2 kg/m2 and children consistently taking metformin took longer to progress (43 ± 21 vs 26 ± 16 months; P = .016).

Discussion

A total of 6.5% of patients with prediabetes developed T2D over a 7-year period. Initial visit laboratory values and weight trajectory may allow for risk stratification, whereas fasting plasma glucose is less helpful. Weight stabilization and metformin therapy could be important interventions for diabetes prevention in children.

Prevalence of metabolic syndrome in adolescents based on three diagnostic definitions: a cross-sectional study

Objective

There is no consensus as to the best criterion for the evaluation of metabolic syndrome (MS), impairing the estimation of its prevalence. This study aims to compare MS estimates using three recommended definitions for adolescents based on a cross-sectional study nested in the Consortium of Brazilian Birth Cohorts in São Luís, Maranhão.

Subjects and methods

A total of 2,515 adolescents aged between 18 and 19 years were evaluated. The criteria of International Diabetes Federation (IDF) and National Cholesterol Education Program Panel III (NCEP-ATP) modified by Cook and cols. (2003) and De Ferranti and cols. (2004) defined SM. To compare the estimates of MS prevalence, the chi-square, Fisher´s exact and Cohen´s Kappa index tests were used.

Results

Among the 2,064 participants evaluated in the final sample. The prevalence of MS ranged from 4.2% (95% CI: 3.3-5.1) to 10.2% (95% CI: 8.8-11.4). When comparing the estimates of MS prevalence in the total sample and by sex, a statistically significant difference was observed. The agreement between the criteria ranged from 0.42 (CI 95%: 0.35-0.49) to 0.55 (CI 95%: 0.48-0.62) in the total sample, 0.33 (CI 95%: 0.24-0.42) to 0.59 (95%CI: 0.47-0.71) among boys and 0.39 (95% CI: 0.26-0.52) to 0.54 (95% CI: 0.44-0.64) among girls.

Conclusion

Different criteria provide different estimates for the prevalence of MS in adolescents, reflecting the importance of establishing a consensus.

Hypertriglyceridemic waist phenotype, hypertriglyceridemic waist-to-height ratio phenotype and abnormal glucose metabolism in adolescents

OBJECTIVE

The purpose of this study was to evaluate the relationship between hypertriglyceridemic waist (HW) phenotype,hypertriglyceridemic waist-to-height ratio (HWHtR) phenotype and abnormal glucose metabolism in adolescents.

METHODS

A secondary analysis was conducted on 2626 adolescents aged 12-19 years in United States. Abnormal glucose metabolism was defined as fasting plasma glucose ≥ 5.6 mmol/L or oral glucose tolerance test 2-h plasma glucose ≥ 7.8 mmol/L or glycohemoglobin A1c ≥ 5.7% or a previous diagnosis of diabetes. The HW phenotype was defined as triglyceride(TG) concentrations ≥ 1.47 mmol/L and waist circumference (WC) ≥ 90th percentile. The HWHtR phenotype was defined as TG concentrations ≥ 1.47 mmol/L and waist-to-height ratio (WHtR) ≥ 0.5.

RESULTS

621(23.6%) adolescents had abnormal glucose metabolism. The prevalences of abnormal glucose metabolism were 22.7% and 40.6% in adolescents without and with HW phenotype. The prevalences of abnormal glucose metabolism were 22.4% and 38.6% in adolescents without and with HWHtR phenotype. Adolescents with HWHtR phenotype were more likely to have abnormal glucose metabolism (OR = 1.548, P = 0.010). The levels of homeostasis model assessment insulin resistance and β cell fuction index were higher in adolescents with HWHtR phenotype than in adolescents without HWHtR phenotype (P < 0.001).

CONCLUSION

The study demonstrates that HWHtR phenotype was closely associated with an increased risk of abnormal glucose metabolism in adolescents. Adolescents with HWHtR phenotype had worsen insulin resistance and increased insulin secretion as a result of compensation.

IMPACT STATEMENT

The study provided a simple method, HWHtR phenotype, for evaluating the status of glucose metabolism in adolescents.

Bariatric surgery normalizes diabetes risk index by one month post-operation

AIM

The Diabetes risk index (DRI) is a composite of NMR-measured lipoproteins and branched chain amino acids predictive of diabetes mellitus development. Bariatric surgery is indicated in patients with severe obesity, many of whom are at high-risk for developing diabetes. Substantial weight loss occurs following bariatric surgery and sustained weight loss likely contributes to reductions in the development of diabetes and cardiovascular disease. However, some evidence suggests that bariatric surgical procedures themselves may contribute to reducing risk of these conditions independent of weight loss. We aimed to investigate DRI and its association with reductions in body weight and adiposity over one year following bariatric surgery.

METHODS

We examined 51 severely obese premenopausal women without diabetes. DRI, BMI, body weight and waist measurements were made before and at 1, 6 and 12 months after Roux-en-Y Gastric Bypass (RYGB) or Sleeve Gastrectomy. Values were compared to healthy women with normal BMI (18.5-24.9 kg/m2; n = 15).

RESULTS

Non-diabetic women with severe obesity (BMI 44.7 ± 6.2 kg/m2) exhibited significantly elevated DRI scores prior to surgery versus controls (35 [26, 39] vs 12 [1, 20]; p < 0.0001). At 1 month after surgery, BMI decreased 5.1 ± 1.1 kg/m2, but DRI decreased so that it no longer differed from that of normal BMI controls (1.9 [1, 17] vs control 12 [1, 20]; p = 0.35). Subjects continued to lose weight, whereas DRI remained similar, throughout follow-up with DRI 1.0 [1, 7] at 12 months. Changes in DRI did not correlate with changes in BMI, body weight or waist circumference at any time during follow-up. There was no difference in change in DRI between surgical procedures or pre-operative metabolic syndrome status.

CONCLUSIONS

Our analysis of DRI scores supports the capacity of bariatric surgery to reduce risk of developing diabetes in severely obese individuals. Our findings suggest that bariatric surgical techniques may have inherent effects that improve cardiometabolic risk independent of reductions in body weight or adiposity.

Evaluation of the hemoglobin a1c test in detecting pediatric prediabetes

Aim: The aim of this study is to evaluate the diagnostic performance of the hemoglobin a1c (Hba1c) test in pediatric prediabetes, and to determine the cut-off value for the pediatric age , to examine the relationship of the Hba1c test between glucose levels,. Materials and Methods: This study was carried out by retrospectively evaluating the data of 548 children. Prediabetes cases were determined by taking fasting and oral glucose tolerance test (OGTT) 2 hour (2h) glucose levels as a reference. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for Hba1c, fasting, and OGTT 2h glucose tests. The area under the curve (AUC) was calculated for each test by receiver-operating characteristic analysis. Results: Based on glucose values, 1.6% of individuals were assigned to the diabetes mellitus, 14.6% to prediabetes, and 83.8% to normoglycemia group. When 5.7 was used as the threshold value for Hba1c in prediabetes, the sensitivity was 31.3%, specificity was 87.8%, PPV was 30.9%, and NPV was 88.0%, AUC:0,686. The optimal cut-off value of Hba1c was determined as 5.35%. At this value, the sensitivity was calculated as 66.3% and the specificity as 61.4%. Conclusion: Although the use of adult HbA1c criteria for the diagnosis of prediabetes in the pediatric ages is controversial due to the differences between the results of OGTT and HbA1c-based tests, prediabetes screening is still important. HbA1c≥5.35 will be useful to follow up on children with prediabetes in terms of risk and to screen them with OGTT.

Prospective Test Performance of Nonfasting Biomarkers to Identify Dysglycemia in Children and Adolescents

INTRODUCTION

Test performance screening measures for dysglycemia have not been evaluated prospectively in youth. This study evaluated the prospective test performance of random glucose (RG), 1-h nonfasting glucose challenge test (1-h GCT), hemoglobin A1c (HbA1c), fructosamine (FA), and 1,5-anhydroglucitol (1,5-AG) for identifying dysglycemia.

METHODS

Youth ages 8-17 years with overweight or obesity (body mass index, BMI, ≥85th percentile) without known diabetes completed nonfasting tests at baseline (n = 176) and returned an average of 1.1 years later for two formal fasting 2-h oral glucose tolerance tests. Outcomes included glucose-defined dysglycemia (fasting plasma glucose ≥100 mg/dL or 2-h plasma glucose ≥140 mg/dL) or elevated HbA1c (≥5.7%). Longitudinal test performance was evaluated using receiver-operating characteristic (ROC) curves and calculation of area under the curve (AUC).

RESULTS

Glucose-defined dysglycemia, elevated HbA1c, and either dysglycemia or elevated HbA1c were present in 15 (8.5%), 11 (6.3%), and 23 (13.1%) participants at baseline, and 16 (9.1%), 18 (10.3%), and 28 (15.9%) participants at follow-up. For prediction of glucose-defined dysglycemia at follow-up, RG, 1-h GCT, and HbA1c had similar performance (0.68 (95% CI: 0.55-0.80), 0.76 (95% CI: 0.64-0.89), and 0.70 (95% CI: 0.56-0.84)), while FA and 1,5-AG performed poorly. For prediction of HbA1c at follow-up, baseline HbA1c had strong performance (AUC 0.93 [95% CI: 0.88-0.98]), RG had moderate performance (AUC 0.67 [95% CI: 0.54-0.79]), while 1-h GCT, FA, and 1,5-AG performed poorly.

CONCLUSION

HbA1c and nonfasting glucose tests had reasonable longitudinal discrimination identifying adolescents at risk for dysglycemia, but performance depended on outcome definition.

Assessment of Overweight, Obesity, Central Obesity, and Type 2 Diabetes among Adolescents in Qatar: A Cross-Sectional Study

Qatar has a high obesity and type 2 diabetes mellitus (T2DM) burden. This study aimed to (1) determine the prevalence of overweight, obesity, and T2DM in 13-17-year-old adolescents and (2) evaluate associations with adolescents' lifestyle and breastfeeding history, parental weight, and familial T2DM history. A cross-sectional study (double-stage cluster sampling) was conducted in 2018-2020 using a self-administered parental and adolescent questionnaire. In the results, 23.4% of the adolescents (107/459) were overweight; 19.9% (91/459) were obese; and 37.6% (171/459) had evidence of central obesity. Random blood sugar (RBS) was suggestive of prediabetes (≥140 mg/dL) for 23 (5.0%) adolescents and T2DM (≥200 mg/dL) for none. In multivariable analysis, obesity was significantly associated with no breastfeeding (OR = 3.17, 95% CI: 1.09-9.26) compared to breastfed adolescents for ≥6 months, with first-degree family history of T2DM (OR = 2.27; 95% CI: 1.22-4.27), with maternal obesity (OR = 2.40; 95% CI: 1.01-5.70), and with acanthosis nigricans in adolescents (OR = 19.8; 95% CI: 8.38-46.9). Central obesity was significantly associated with maternal obesity (OR = 2.21; 95% CI: 1.14-4.27) and with acanthosis nigricans (OR = 3.67; 95% CI: 1.88-7.18). Acanthosis nigricans (OR = 4.06; 95% CI: 1.41-11.7) was the only factor associated with elevated RBS. Addressing future disease burden among adults in Qatar will require extensive health and well-being programs, focused on healthy lifestyles and behaviors such as nutritious diets, physical activity, stress management, and self-care.

The performance of glycated albumin as a biomarker of hyperglycemia and cardiometabolic risk in children and adolescents in the United States

OBJECTIVE

Diabetes and prediabetes are growing concerns among US youth. Fasting glucose (FG) and HbA1c are standard diabetes screening tests, but HbA1c may be unreliable in some settings and fasting is burdensome in children. Glycated albumin (GA) is a non-fasting test that was recently cleared for clinical use in the United States, but studies in youth without diabetes are limited.

RESEARCH DESIGN AND METHODS

We conducted a cross-sectional analysis in 6826 youth without diabetes aged 8-19 years in the 1999-2004 National Health and Nutrition Examination Survey. We evaluated the associations of GA with HbA1c, FG, and cardiometabolic risk factors.

RESULTS

GA was poorly correlated with HbA1c (ρ = 0.074) and FG (ρ = -0.047) and was negatively associated with body mass index (BMI) and cardiometabolic risk factors. Compared to youth in the highest tertile of GA (≥13.5%), those in the lowest GA tertile (<12.4%) had a higher prevalence of obesity (29.9% vs. 7.6%), low high-density lipoprotein cholesterol (29.7% vs. 16.5%), and hypertensive blood pressure (4.0% vs. 2.7%). These inverse associations persisted after adjustment for age, sex, race/ethnicity, serum albumin, and C-reactive protein.

CONCLUSIONS

GA was poorly correlated with traditional markers of hyperglycemia in youth without diabetes. Counterintuitively, there was a negative association between GA and BMI. Among youth without diabetes, GA does not identify youth at high cardiometabolic risk, and it does not appear to be an appropriate biomarker for screening of hyperglycemia.

Youth prediabetes and type 2 diabetes: Risk factors and prevalence of dysglycaemia

BACKGROUND

The American Diabetes Association recommends risk-based screening for dysglycaemia (prediabetes and type 2 diabetes) in youth with overweight/obesity plus ≥1 risk factor. However, evidence for these recommendations is lacking.

OBJECTIVES

Examine the association between the number of risk factors and the prevalence of dysglycaemia in youth with overweight/obesity at initial presentation.

METHODS

In a paediatric obesity registry, youth (>10 and <20 years old, body mass index ≥85th percentile) were categorized into four groups according to number of risk factors (1, 2, 3 and ≥4). Based on oral glucose tolerance test, participants were classified into normal glucose tolerance or dysglycaemia.

RESULTS

Of 635 youth, 31.5% had prediabetes and 6.1% had type 2 diabetes. The prevalence of dysglycaemia was 23.1% with 1 risk factor and increased to 44.9% with ≥4 risk factors (p = 0.025). Dyslipidaemia, family history of type 2 diabetes and maternal history of gestational diabetes were significantly associated with dysglycaemia. Fasting and 2-h insulin, 2-h glucose increased (all p < 0.0001) and ALT increased (p = 0.001) with increasing risk factors. Insulin sensitivity and β-cell function deteriorated significantly with increasing risk factors.

CONCLUSION

Screening for dysglycaemia in youth with obesity and any additional risk factor is warranted to target early management.

Comparing the Fasting and Random-Fed Metabolome Response to an Oral Glucose Tolerance Test in Children and Adolescents: Implications of Sex, Obesity, and Insulin Resistance

As the incidence of obesity and type 2 diabetes (T2D) is occurring at a younger age, studying adolescent nutrient metabolism can provide insights on the development of T2D. Metabolic challenges, including an oral glucose tolerance test (OGTT) can assess the effects of perturbations in nutrient metabolism. Here, we present alterations in the global metabolome in response to an OGTT, classifying the influence of obesity and insulin resistance (IR) in adolescents that arrived at the clinic fasted and in a random-fed state. Participants were recruited as lean (n = 55, aged 8–17 years, BMI percentile 5–85%) and overweight and obese (OVOB, n = 228, aged 8–17 years, BMI percentile ≥ 85%). Untargeted metabolomics profiled 246 annotated metabolites in plasma at t0 and t60 min during the OGTT. Our results suggest that obesity and IR influence the switch from fatty acid (FA) to glucose oxidation in response to the OGTT. Obesity was associated with a blunted decline of acylcarnitines and fatty acid oxidation intermediates. In females, metabolites from the Fasted and Random-Fed OGTT were associated with HOMA-IR, including diacylglycerols, leucine/isoleucine, acylcarnitines, and phosphocholines. Our results indicate that at an early age, obesity and IR may influence the metabolome dynamics in response to a glucose challenge.

Who should return for an oral glucose tolerance test? A proposed clinical pathway based on retrospective analysis of 332 children

OBJECTIVES

Fasting plasma glucose or oral glucose tolerance test (OGTT) is the traditional diagnostic tool for type 2 diabetes (T2DM). However, fasting is required and implementation in all overweight/obese subjects is not practical. This study aimed to formulate a clinical pathway to stratify subjects according to their risk of abnormal OGTT.

METHODS

This retrospective study included patients with overweight or obesity who had undergone OGTT in a tertiary paediatric unit from 2012 to 2018. The optimal haemoglobin A1c (HbA1c) cutoff that predicts abnormal OGTT was evaluated. Other non-fasting parameters, in combination with this HbA1c cutoff, were also explored as predictors of abnormal OGTT.

RESULTS

Three hundred and thirty-two patients (boys: 54.2%, Chinese: 97.3%) were included for analysis, of which, 272 (81.9%) patients had normal OGTT while 60 (18.0%) patients had abnormal OGTT (prediabetes or T2DM). Optimal HbA1c predicting abnormal OGTT was 5.5% (AUC 0.71; sensitivity of 66.7% and specificity of 71%). When HbA1c≥5.5% was combined with positive family history and abnormal alanine transaminase (ALT) level, the positive predictive value for abnormal OGTT was increased from 33.6 to 61.6%.

CONCLUSIONS

HbA1c, family history of T2DM and ALT level could be used to derive a clinical pathway to stratify children who have high risk of abnormal OGTT.

Glycated haemoglobin as a screening test for abnormal glucose homeostasis in childhood obesity

AIM

To estimate the proportion of type 2 diabetes mellitus and abnormal glucose homeostasis in childhood obesity and assess the predictive role of HbA_1c as a diagnostic marker compared with oral glucose tolerance testing (OGTT).

METHODS

A retrospective study in a tertiary paediatric hospital. Data were collected on all overweight or obese children who underwent routine OGTT between 2012 and 2016. Ethnicity, anthropometry, comorbidities and other risk factors associated with diabetes were recorded systematically. Fasting venous glucose, insulin and HbA_1c values, along with 120-min venous glucose were recorded. Receiver operating characteristic (ROC) curve analysis was performed to derive optimum thresholds of HbA_1c for detection of type 2 diabetes, impaired fasting glucose (IFG) and impaired glucose tolerance (IGT). Predictive HbA_1c thresholds for the detection of abnormal glucose homeostasis in children with obesity were calculated.

RESULTS

Of 156 children, 13 (8%, 10 female, 10 Asian) had type 2 diabetes, 95 (61%) had normal glucose tolerance, 18 (12%) had isolated IFG, 19 (12%) had isolated IGT, and another 11 (7%) had both IFG and IGT. The proportion of abnormal glucose homeostasis was 39%. ROC curve analysis demonstrated that HbA_1c ≥ 42 mmol/mol (6.0%) predicted type 2 diabetes (specificity 95%, sensitivity 85%) but performed moderately for IFG (specificity 46%, sensitivity 78%) and IGT (specificity 78%, sensitivity 55%).

CONCLUSION

Despite HbA_1c being a less-sensitive diagnostic tool compared with OGTT for children with IFG and IGT, it is reliable in detecting type 2 diabetes in asymptomatic children with obesity, instead of the labour- and cost-intensive OGTT.

A Novel Indicator of Children's Lipid Accumulation Product Associated with Impaired Fasting Glucose in Chinese Children and Adolescents

BACKGROUND

Diabetes is one of the most prevalent noncommunicable diseases worldwide. Children's lipid accumulation product (CLAP) is a novel indicator to show children's lipid accumulation and is effectively associated with metabolic syndrome among children and adolescents. The aim of the present study was to explore an association between CLAP and impaired fasting glucose (IFG) in Chinese children and adolescents.

METHODS

A total of 683 children and adolescents aged 8-15 years were recruited using the stratified cluster sampling method in this cross-sectional study and were measured for body height, weight, waist circumference (WC), abdominal skinfold thickness (AST), triglycerides (TG), fasting plasma glucose, dietary behaviors and physical activities. A logistic regression model and receiver operating characteristic (ROC) curve were used to compare the effects of CLAP for predicting IFG.

RESULTS

The prevalence of IFG in children and adolescents was 13.8%: 16.9% in boys and 10.1% in girls (P<0.05). The CLAP, height, weight, WC, AST, waist-to-height ratio (WHtR), and TG among boys with IFG were significantly higher than those among boys without IFG (P<0.05). The area under the ROC curve of CLAP for predicting IFG (0.637 (0.562-0.712)) was higher than those of WC, WHtR, AST, and TG. The cutoff point of P ₇₅ CLAP was the optimal value to predict IFG among boys, and the OR (95% CI) was 2.48 (1.40-4.42) and area under the ROC curve was 0.595 (0.513-0.676).

CONCLUSION

The CLAP was a novel indicator associated with IFG in Chinese boys, and it performed better than WC, WHtR, AST and TG.

Comparison of HbA1c and OGTT for the diagnosis of type 2 diabetes in children at risk of diabetes

BACKGROUND

The aim of this study was to evaluate the correlation between plasma glucose and HbA1c and the diagnostic accuracy of HbA1c as a screening tool to identify asymptomatic diabetes mellitus in children and adolescents with obesity or asymptomatic glucosuria.

METHODS

A total of 190 subjects who underwent an oral glucose tolerance test (OGTT) to confirm diabetes were categorized into normal glucose tolerance (NGT; n = 117), impaired glucose tolerance (IGT; n = 33), and diabetes (DM; n = 40) according to the OGTT. Forty-seven patients with DM were diagnosed by either OGTT or HbA1c levels. The diagnostic accuracy for the detection of diabetes is based on 47 patients. Laboratory tests were performed after 12 h of fasting.

RESULTS

According to the HbA1c criterion, 107 (55.3%) subjects were in the NGT group, 41 (21.6%) were in the IGT group, and 42 (22.1%) were in the DM group. Diagnostic sensitivities of HbA1c and 2-hour plasma glucose level following OGTT (2-h OGTT) for DM were significantly higher than that of fasting plasma glucose, FPG (89.4, 85.1 vs. 63.8%). In addition, the area under the curves of diagnostic criteria was 0.970 for HbA1c, 0.939 for FPG and 0.977 for 2-h OGTT. Mean FPG and 2-h OGTT for HbA1c level >6.5% were 115.2 mg/dL and 181.8 mg/dL, respectively. The optimal HbA1c level cut-off point for predicting DM is 6.15%, with a sensitivity of 95.7% in Korean children and adolescents.

CONCLUSION

The HbA1c criterion ≥6.5% was adequate to detect DM among Korean children and adolescents with obesity or asymptomatic glucosuria. We also recommend HbA1c level of 6.15% as the optimal cut-off point for detecting DM in Korean children and adolescents.

Evaluation of ADA HbA1c criteria in the diagnosis of pre-diabetes and diabetes in a population of Chinese adolescents and young adults at high risk for diabetes: a cross-sectional study

OBJECTIVE

We aimed to assess haemoglobin A1c (HbA1c) for the diagnosis of pre-diabetes and diabetes in a population of Chinese youths at risk of metabolic syndrome.

SETTING

Beijing, China.

PARTICIPANTS

A total of 581 subjects aged 14-28 years underwent evaluation including an oral glucose tolerance test (OGTT). Insulin sensitivity, β-cell function and a number of cardiovascular disease risk factors were evaluated. Receiver operating characteristic (ROC) curves were used to assess the screening efficacy of HbA1c.

RESULTS

Using OGTT data as a standard, the majority (70.0%, 7/10) of subjects with diabetes would have been diagnosed with HbA1c ≥6.5%. In contrast, only 28.1% (16/57) of subjects with pre-diabetes possessed elevated HbA1cs, while the majority (68.4%) had normal HbA1cs. On the contrary, a total of 8.1% (39/479) of youths in the normal HbA1c category (<5.7%) and 21.3% in the pre-diabetes category had pre-diabetes. In the ROC analysis, the area under the curve (AUC) for HbA1c identifying pre-diabetes was 0.680(95% CI 0.640 to 0.719); the optimal threshold was 5.5%, with a sensitivity of 61.4% and specificity of 68.5%. For type 2 diabetes mellitus, the AUC for HbA1c was 0.970 (0.952 to 0.982), and the optimal threshold was 6.1%, with a sensitivity of 90.0% and a specificity of 98.7%. Applying these new cut-offs, pre-diabetic participants (HbA1c 5.5%-6.1%) had lower disposition index and higher risk of dyslipidaemia (OR=1.61,95% CI 1.10 to 2.37) and metabolic syndrome (OR=2.09, 1.27 to 3.45) than those with normal HbA1c (<5.5%).

CONCLUSION

The American Diabetes Association's established HbA1c criteria for pre-diabetes and diabetes (5.7% and 6.5%) may not be appropriately applied to adolescents and young adults in China. Our findings suggest that those with HbA1c of 5.5%-6.1% already exhibit impaired β-cell function and increased cardiometabolic risk factors which may warrant intervention.

TRIAL REGISTRATION NUMBER

NCT03421444.

Biological and socioeconomic determinants of prediabetes in youth: an analysis using 2007 to 2011 Canadian Health Measures Surveys

OBJECTIVES

To describe rates of prediabetes among youth in Canada and the associated social and biological characteristics.

METHODS

We analyzed the cross-sectional data from the first (2007-2009) and second (2009-2011) cycles of the Canadian Health Measures Survey (CHMS) for youth aged 6-19 years. Prediabetes was defined using the glycated hemoglobin (A1C) guidelines set out by the American Diabetes Association (ADA) and the Canadian Diabetes Association (CDA) of A1C ranges 5.7-6.4% (38.8-46.4 mmol/mol) and 6.0-6.4% (42.1-46.4 mmol/mol), respectively.

RESULTS

An elevated A1C was observed in 22.8% of our sample (n = 3449) based on the ADA definition and 5.2% of youth using the CDA definition. Independent predictors in a fully adjusted model for prediabetes were non-White (odds ratio (OR) 2.62: 95% Confidence intervals 2.05-3.35), obese (OR 1.53: 1.19-1.96), less physically active youth (0.97: 0.95-0.99), and parents with high school education or less (1.34: 1.02-1.74). Moreover, significant regional variations were noted with higher rates for all regions except Ontario.

CONCLUSION

Prediabetes is relatively common in Canada and associated with common biologic and socioeconomic factors. Importantly, regular physical activity was significantly associated with reduced odds of prediabetes. Targeted screening and continued emphasis on physical activity may help curb the increasing rates of prediabetes.

Identifying Prediabetes and Type 2 Diabetes in Asymptomatic Youth: Should HbA1c Be Used as a Diagnostic Approach?

PURPOSE OF REVIEW

Because the incidence of type 2 diabetes and prediabetes in children is rising, routine screening of those at risk is recommended. In 2010, the ADA made the recommendation to include hemoglobin A1c (HbA1c) as a diagnostic test for diabetes, in addition to the oral glucose tolerance test or fasting plasma glucose. Our objective was to assess the pediatric literature with regard to HbA1c test performance and discuss advantages and disadvantages of use of the test for diagnostic purposes.

RECENT FINDINGS

HbA1c has a number of advantages, including elimination of the need for fasting, lower variability, assay standardization, and long-term association with future development of diabetes. It also has many drawbacks. It can be affected by a number of non-glycemic factors, including red blood cell turnover, hemoglobinopathies, medications, race, and age. In particular, it performs differently in children compared with adults, generally with lower sensitivity for prediabetes (as low as 0-5% in children vs 23-27% in adults) and lower area under the receiver operating characteristic curve (AUC) (0.53 vs 0.73 for prediabetes), and it has lower efficacy at a higher cost, compared with other tests of glycemia. Finally, HbA1c may perform very differently across diverse populations according to race/ethnicity; in Chinese populations, the proportion of individuals classified with prediabetes based on HbA1c predominates compared with IFG (77% for HbA1c vs 27.7% for IFG), whereas in US populations, it is the opposite (24.8% for HbA1c vs 80.1% for FPG). HbA1c is controversial because although it is convenient, it is not a true measure of glycemia. The interpretation of HbA1c results requires a nuanced understanding that many primary care physicians who are ordering the test in greater numbers do not possess. Alternative markers of glycemia may hold promise for the future but are not yet endorsed for use in practice. Further studies are needed to determine appropriate thresholds for screening tests and the long-term impact of screening and identification.

Low association between fasting and OGTT stimulated glucose levels with HbA1c in overweight children and adolescents

BACKGROUND

Diabetes and prediabetes are defined based on different methods such as fasting glucose, glucose at 2-hour in oral glucose tolerance test (OGTT), and glycated hemoglobin A1c (HbA1c). These parameters probably describe different deteriorations in glucose metabolism limiting the exchange between each other in definitions of diabetes.

OBJECTIVE

To investigate the relationship between OGTT and HbA1c in overweight and obese children and adolescents living in Germany.

METHODS

Study population: Overweight and obese children and adolescents (n = 4848; 2668 female) aged 7 to 17 years without known diabetes. The study population was stratified into the following subgroups: normal glucose tolerance, prediabetes, diabetes according to OGTT and/or HbA1c categories, confirmed diagnosis of diabetes.

RESULTS

In the entire study group fasting plasma glucose (FPG) correlated weakly to 2-hour glucose (r = 0.26), FPG correlated weakly to HbA1c (r = 0.18), and 2-hour glucose correlated weakly to HbA1c (r = 0.17, all P < .001). Patients with confirmed diabetes showed a very high correlation between FPG and 2-hour glucose (r = 0.73, n = 50). Moderate correlations could be found for patients with impaired fasting glucose (2-hour glucose vs HbA1c: r = 0.30, n = 436), for patients with diabetes according to OGTT and/or HbA1c (FPG vs 2-hour glucose: r = 0.43; 2-hour glucose vs HbA1c: r = -0.30, n = 115) and for patients with confirmed diabetes (2-hour glucose vs HbA1c: r = -0.47, all P < .001).

CONCLUSIONS

Because FPG, 2-hour glucose, and HbA1c correlated only weakly we propose that these parameters, particularly in the normal range, might reflect distinct aspects of carbohydrate metabolism.

Alternate glycemic markers reflect glycemic variability in continuous glucose monitoring in youth with prediabetes and type 2 diabetes

OBJECTIVE

To determine whether the alternate glycemic markers, fructosamine (FA), glycated albumin (GA), and 1,5-anhydroglucitol (1,5AG), predict glycemic variability captured by continuous glucose monitoring (CGM) in obese youth with prediabetes and type 2 diabetes (T2D).

STUDY DESIGN

Youth with BMI ≥85th%ile, 10-18 years, had collection of fasting plasma glucose (FPG), hemoglobin A1c (HbA1c), FA, GA, and 1,5AG and 72 hours of CGM. Participants with HbA1c ≥5.7% were included. Relationships between glycemic markers and CGM variables were determined with Spearman correlation coefficients. Linear models were used to examine the association between alternate markers and CGM measures of glycemic variability-standard deviation (SD) and mean amplitude of glycemic excursions (MAGE)-after controlling for HbA1c.

RESULTS

Total n = 56; Median (25th%ile, 75th%ile) age = 14.3 years (12.5, 15.9), 32% male, 64% Hispanic, 20% black, 13% white, HbA1c = 5.9% (5.8, 6.3), FA=211 mmol/L (200, 226), GA= 12% (11%, 12%), and 1,5AG = 22mcg/mL (19, 26). HbA1c correlated with average sensor glucose, AUC, SD, MAGE, and %time > 140 mg/dL. FA and GA correlated with average and peak sensor glucose, %time >140 and >200 mg/dL, and MAGE. GA also correlated with SD and AUC180. 1,5AG correlated with peak glucose, AUC180, SD, and MAGE. After adjusting for HbA1c, all 3 markers independently predicted MAGE; FA and GA independently predicted SD.

CONCLUSIONS

Alternate glycemic markers predict glycemic variability as measured by CGM in youth with prediabetes and T2D. After adjusting for HbA1c, these alternate markers continued to predict components of glycemic variability detected by CGM.

Comparison of A1C to Oral Glucose Tolerance Test for the Diagnosis of Prediabetes in Overweight and Obese Youth

IN BRIEF This study reports performance of A1C against the oral glucose tolerance test (OGTT) in predicting prediabetes among overweight and obese African-American and Caribbean children. A retrospective chart review was completed for 230 children. Receiver operating characteristic curves were generated to find the predictive performances of different tests against the OGTT. A1C alone is a poor discriminator of prediabetes in our study population, with low sensitivity (70%) and specificity (48.8%). BMI z score, A1C, and homeostatic model assessment of insulin resistance are significant predictors of prediabetes and, when taken together, provide better discrimination for prediabetes.

Type 2 diabetes in adolescents: a severe phenotype posing major clinical challenges and public health burden

Type 2 diabetes in adolescence manifests as a severe progressive form of diabetes that frequently presents with complications, responds poorly to treatment, and results in rapid progression of microvascular and macrovascular complications. Although overall still a rare disease, adolescent type 2 diabetes now poses major challenges to paediatric and adult diabetes services in many countries. Therapeutic options are heavily curtailed by a dearth of knowledge about the condition, with low numbers of participants and poor trial recruitment impeding research. Together with lifestyle modification, metformin remains the first-line therapy for adolescents with type 2 diabetes, although the majority rapidly progress to treatment failure and insulin therapy. Early bariatric surgery is controversial but has great potential to transform outcomes. Health systems must respond by both concentrating patients in specialist clinical services integrated with translational research programmes, but also by joining up with local health and social care services to improve engagement and uptake of services.

Pediatric Obesity-Assessment, Treatment, and Prevention: An Endocrine Society Clinical Practice Guideline

COSPONSORING ASSOCIATIONS

The European Society of Endocrinology and the Pediatric Endocrine Society. This guideline was funded by the Endocrine Society.

OBJECTIVE

To formulate clinical practice guidelines for the assessment, treatment, and prevention of pediatric obesity.

PARTICIPANTS

The participants include an Endocrine Society-appointed Task Force of 6 experts, a methodologist, and a medical writer.

EVIDENCE

This evidence-based guideline was developed using the Grading of Recommendations, Assessment, Development, and Evaluation approach to describe the strength of recommendations and the quality of evidence. The Task Force commissioned 2 systematic reviews and used the best available evidence from other published systematic reviews and individual studies.

CONSENSUS PROCESS

One group meeting, several conference calls, and e-mail communications enabled consensus. Endocrine Society committees and members and co-sponsoring organizations reviewed and commented on preliminary drafts of this guideline.

CONCLUSION

Pediatric obesity remains an ongoing serious international health concern affecting ∼17% of US children and adolescents, threatening their adult health and longevity. Pediatric obesity has its basis in genetic susceptibilities influenced by a permissive environment starting in utero and extending through childhood and adolescence. Endocrine etiologies for obesity are rare and usually are accompanied by attenuated growth patterns. Pediatric comorbidities are common and long-term health complications often result; screening for comorbidities of obesity should be applied in a hierarchal, logical manner for early identification before more serious complications result. Genetic screening for rare syndromes is indicated only in the presence of specific historical or physical features. The psychological toll of pediatric obesity on the individual and family necessitates screening for mental health issues and counseling as indicated. The prevention of pediatric obesity by promoting healthful diet, activity, and environment should be a primary goal, as achieving effective, long-lasting results with lifestyle modification once obesity occurs is difficult. Although some behavioral and pharmacotherapy studies report modest success, additional research into accessible and effective methods for preventing and treating pediatric obesity is needed. The use of weight loss medications during childhood and adolescence should be restricted to clinical trials. Increasing evidence demonstrates the effectiveness of bariatric surgery in the most seriously affected mature teenagers who have failed lifestyle modification, but the use of surgery requires experienced teams with resources for long-term follow-up. Adolescents undergoing lifestyle therapy, medication regimens, or bariatric surgery for obesity will need cohesive planning to help them effectively transition to adult care, with continued necessary monitoring, support, and intervention. Transition programs for obesity are an uncharted area requiring further research for efficacy. Despite a significant increase in research on pediatric obesity since the initial publication of these guidelines 8 years ago, further study is needed of the genetic and biological factors that increase the risk of weight gain and influence the response to therapeutic interventions. Also needed are more studies to better understand the genetic and biological factors that cause an obese individual to manifest one comorbidity vs another or to be free of comorbidities. Furthermore, continued investigation into the most effective methods of preventing and treating obesity and into methods for changing environmental and economic factors that will lead to worldwide cultural changes in diet and activity should be priorities. Particular attention to determining ways to effect systemic changes in food environments and total daily mobility, as well as methods for sustaining healthy body mass index changes, is of importance.

High predictability of impaired glucose tolerance by combining cardiometabolic screening parameters in obese children

BACKGROUND

There is debate on which overweight and obese children should be screened for the presence of impaired glucose tolerance (IGT) by oral glucose tolerance testing (OGTT). The objective of the study was to identify risk factors predictive of the presence of IGT.

METHODS

In a cohort of overweight children, who underwent OGTT, we determined the association of anthropometric and laboratory parameters with IGT and whether combining parameters improved the sensitivity of screening for IGT.

RESULTS

Out of 145 patients, IGT was present in 11, of whom two had impaired fasting glucose (IFG). Elevated blood pressure (p=0.025) and elevated liver enzymes (p=0.003) were associated with IGT, whereas IFG was not (p=0.067), screening patients with either one of these parameters predicted IGT with a high sensitivity of 1.00, and a number needed to screen of 5.7.

CONCLUSIONS

Screening all patients with either IFG, presence of elevated blood pressure and elevated liver enzymes, significantly increases predictability of IGT compared to using IFG alone.

Screening for type 2 diabetes and prediabetes in obese youth: evaluating alternate markers of glycemia - 1,5-anhydroglucitol, fructosamine, and glycated albumin

Hemoglobin A1c (HbA1c) is increasingly performed over the oral glucose tolerance test (OGTT) as the initial screening test for type 2 diabetes in youth. However, the optimal strategy for identifying type 2 diabetes in youth remains controversial. Alternate glycemic markers have been proposed as potentially useful tools for diabetes screening. We examined the relationships among fructosamine (FA), glycated albumin (GA), and 1,5-anhydroglucitol (1,5-AG) with traditional screening tests, HbA1c and OGTT. Youth 10-18 yrs, BMI ≥85th‰, and HbA1c <7.5% had a single visit with measurement of HbA1c, 1,5-AG, FA, GA, and a standard OGTT. Distributions of FA, GA, and 1,5-AG by HbA1c and 2-hour glucose (2hG) categories were compared. Receiver operating characteristic (ROC)-curves were generated to determine the cut points at which alternate markers maximized sensitivity and specificity for predicting prediabetes and diabetes. One hundred and seventeen, 62% female, 59% Hispanic, 22% White, 17% black, median 14.1 yr, and body mass index (BMI) z-score 2.3 participated. Median values of each alternate marker differed significantly between prediabetes and diabetes HbA1c and 2hG categories (p < 0.017). Only GA medians differed (p = 0.006) between normal and prediabetes HbA1c. Area under the receiver operating characteristic curves (ROC-AUCs) for alternate markers as predictors of prediabetes (0.5-0.66) were low; however, alternate marker ROC-AUCs for identifying diabetes (0.82-0.98) were excellent. Although the alternate markers were poor predictors of prediabetes, they all performed well predicting diabetes by 2hG and HbA1c. Whereas the usefulness of these markers for identifying prediabetes is limited, they may be useful in certain scenarios as second line screening tools for diabetes in overweight/obese youth.

The prevalence, risk factors, and screening measure for prediabetes and diabetes among Emirati overweight/obese children and adolescents

Background

The aim of the study was to estimate the prevalence of prediabetes and type 2 diabetes (T2D) among overweight/obese children and adolescents using different diagnostic/screening methods in comparison.

Methods

We recruited overweight/obese Emirati students; grade 6–12 (age 11–17 years) from 16 government schools in Sharjah (UAE). Anthropometric, demographic, and clinical history data was measured by standard methods. Body mass index (BMI) was categorized according to BMI percentile charts for age and sex – CDC. Capillary fasting blood glucose (FBG) and glycated hemoglobin (HbA1c) were measured by finger prick test, followed by confirmatory oral glucose tolerance tests (OGTT) and venous HbA1c for students with abnormal capillary FBG and/or HbA1c.

Results

Of a total of 1034 participants (45 % females) median age 14.7 years, 443 (43 %) students had abnormal screening results. The prevalence of prediabetes and T2D was 5.4 % and 0.87 %, respectively, based on OGTT (gold standard). HbA1c showed a considerable discrepancy regarding the prevalence of prediabetes (21.9 %), but not diabetes. There was a statistically significant difference in the BMI Z-scores between the three different groups of students showing normal glycemic testing, prediabetes and T2D (p = 0.041). Univariate logistic regression analysis showed that glycemic status was significantly associated with family history of T2D first-degree relatives [OR 1.87: 95 % CI: 1.04–3.36; P = 0.036], parents employment [OR 1.79: 95 % CI: 1.06–3.02; P = 0.029] and levels of triglycerides [OR 2.28: 95 % CI: 1.11–4.68; P = 0.024].

Conclusions

The prevalence of prediabetes and diabetes was high among overweight/obese Emirati children and adolescents. The numbers for prediabetes were considerably higher when using HbA1c as compared to OGTT. Overall adiposity, family history of T2D, employment and high levels of triglycerides were risk factors associated with abnormal glycemic testing.

Prevalence of high normal FBS and prediabetes among adolescents in Birjand, East of Iran, 2012

BACKGROUND AND OBJECTIVES

To determine the prevalence of impaired fasting glucose in adolescents in Birjand city in eastern Iran.

MATERIALS AND METHODS

This cross-sectional study was done on 2653 students aged 11-18 years selected through multi-stage stratified and random sampling. Fasting blood glucose (FBS) of these students was measured applying the enzymatic process. The obtained data were analyzed by means of SPSS software (V: 15) and statistical tests T and X2.

RESULTS

The mean age of individual was 14.5 ± 2 years. Mean FBS of the whole population was 89.8 ± 9.8 mg/dl, but it was significantly higher among boys than girls (P < 0.001). Out of the whole subjects (92.4%), 1,328 (95.1%) of the girls and 1,122 (89.3%) of the boys, FBS was less than 100 mg/dl among whom 64.4% had FBS above 86 mg/dl. In 200 subjects (7.5%) of whole population, FBS was 100-125 mg/dl; with that of the boys was 2.3 times than the girls revealing a prediabetes condition: OR = 2.3(CI: 1.7-3.2). Among the students, 3 (0.1%) had an FBS > 126 mg/dl. Mean blood glucose was significant regarding age and sex.

CONCLUSIONS

High prevalence of high FBS (within normal range) among adolescents is warning and requires special attention of health officials. Screening of children and adolescents in order to identify those at risk and plan for intervening is urgent to prevent type-2 diabetes epidemic and following cardiovascular complications in the Society.

Hemoglobin A1c assay variations and implications for diabetes screening in obese youth

BACKGROUND

Standardization of the hemoglobin A1c (A1c) assay has led to its increasing utilization as a screening tool for the diagnosis of prediabetes and type 2 diabetes in youth. However, significant A1c assay variability remains and has implications for clinical management.

OBJECTIVE

To describe our center's experiences with A1c results in youth and to evaluate inter-method differences and their clinical implications.

SUBJECTS

Seventy-five youth (aged 10-18 yr old), body mass index (BMI) ≥85th‰ participated.

METHODS

Seventy-two participants had two A1c values performed on the same sample, one via immunoassay (DCA Vantage Analyzer, A1c1 ) and the other via high performance liquid chromatography (Bio-Rad Variant II, A1c2 ). Nineteen had A1c run on two immunoassay devices (A1c1 and Dimensions Vista, A1c3 ).

RESULTS

Mean age of participants was 13.9 years, BMI% 97.89%, 33% male, 16% white, 21% black, and 61% Hispanic (H). Mean A1c1 was 5.68% ± 0.38 vs. a mean A1c2 of 5.73% ± 0.39, p = 0.049. Concordance in diabetes status between methods was achieved in 79% of subjects. Nineteen subjects with A1c3 results had testing performed an average of 22 ± 9 days prior to A1c1 . Mean A1c3 was 6.24% ± 0.4, compared to a mean A1c1 of 5.74% ± 0.31, (p < 0.0001). A1c1 was on average systematically -0.5 ± 0.28 lower compared to A1c3 . There was poor agreement in diabetes classification between A1c1 and A1c3 , with a concordance in classification between methods of only 36.8%.

CONCLUSIONS

Clinically significant inter-method A1c variability exists that impacts patient classification and treatment recommendations. In the screening of obese youth for diabetes, A1c results should be interpreted with caution.

Five-region study finds no evidence of undiagnosed type 2 diabetes in Swedish 11- to 13-year-olds

AIM

Childhood obesity is now an established public health problem in most developed countries, and there is concern about a parallel increase of type 2 diabetes. The aim of this study was to estimate the prevalence of undiagnosed type 2 diabetes in overweight Swedish school children from 11 to 13 years of age.

METHODS

Body mass index (BMI) was measured in 5528 schoolchildren in the 6th grade, from 11 to 13 years of age, in five different regions in Sweden. Overweight was defined by international age- and sex-specific BMI cut-offs, corresponding to adult BMI cut-offs of 25 kg/m(2) at 18 years of age (ISO-BMI ≥25, n = 1275). Haemoglobin A1c (HbA1c) was measured in 1126 children with ISO-BMI ≥25. Children with a Diabetes Control and Complications Trial aligned HbA1c ≥6.1% on two occasions underwent an oral glucose tolerance test (OGTT) to establish the diabetes diagnosis.

RESULTS

Of 1126 children with ISO-BMI ≥25, 24 (2.1%) had at least one HbA1c value ≥6.1%. Three of them had HbA1c ≥6.1% on two occasions, and all of them had a normal OGTT.

CONCLUSION

In this cross-sectional, population-based screening study of a high-risk group of 11- to 13-year-old Swedish school children, we found no indication of undiagnosed diabetes or impaired glucose tolerance.

Adolescent prediabetes in a high-risk Middle East country: a cross-sectional study

Objective

To estimate the prevalence of prediabetes in adolescents living in a high-risk country and to detect risk factors associated with this disorder.

Design

Survey questionnaire combined with physical measurements and blood sugar determination.

Setting

Doha, capital city of Qatar.

Participants

A total of 1694 male and female students aged 11–18 years without previously diagnosed diabetes enrolled in four schools.

Main outcome measure

Blood sugar measurements. Other measured variables included gender, height, weight, abdominal circumference, country of origin, family history of diabetes and frequency of exercise.

Results

Using a random blood sugar ≥7.8 mmol/L or a fasting blood sugar ≥5.5 mmol/L as cutpoints, we identified 4.2% of students (56 boys, 15 girls) as probable prediabetics. In a multivariate model, being boys (OR 3.2, 95% CI 1.7–6.2), having a diabetic parent (OR 1.9, 95% CI 1.1–3.2) or having a waist-to-height ratio >0.5 (OR 1.8, 95% CI 1.1–3.0) were significantly associated with being a prediabetic. The parental origin of diabetes had a differential effect upon blood sugar. The mean random blood sugar in students with a maternal inheritance pattern of diabetes was 5.61 mmol/L ± 1.0, compared to 5.39 mmol/L ± 0.89 in students with a paternal inheritance pattern (p = 0.02).

Conclusions

In a country with a high risk of adult diabetes, we identified 4.2% of students aged 11–18 as being prediabetic. Risk factors associated with prediabetes included male gender, family history of diabetes and waist-to-height ratio >0.5.

Screening obese children and adolescents for prediabetes and/or type 2 diabetes in pediatric practices: a validation study

BACKGROUND

Increased prevalence of type 2 diabetes mellitus (T2DM) makes it important for pediatricians to use effective screening tools for risk assessment of prediabetes/T2DM in children.

METHODS

Children (n = 149) who had an oral glucose tolerance test (OGTT) and glycated hemoglobin (HbA1c) were studied. American Diabetes Association recommended screening criteria-HbA1c ≥5.7% and fasting plasma glucose (FPG) ≥100 mg/dL-were compared against OGTT. The homeostatic model assessment of insulin resistance (HOMA-IR), a mathematical index derived from fasting insulin and glucose, was compared with OGTT. We studied whether combining screening tests (HbA1c and fasting glucose or HbA1c and HOMA-IR) improved accuracy of prediction of the OGTT.

RESULTS

HbA1c of ≥5.7% had a sensitivity of 75% and specificity of 57% when compared with the OGTT. Combining screening tests (HbA1c ≥5.7% and FPG ≥100 mg/dL; HbA1c ≥5.7% and HOMA-IR ≥3.4) resulted in improved sensitivity (95.5% for each), with the HbA1c-FPG doing better than the HbA1c-HOMA-IR combination in terms of ability to rule out prediabetes (likelihood ratio [LR]) negative. 0.07 vs 0.14).

CONCLUSIONS

HbA1c of ≥5.7% provided fair discrimination of glucose tolerance compared with the OGTT. The combination of HbA1c and FPG is a useful method for identifying children who require an OGTT.

Divergence between HbA1c and fasting glucose through childhood: implications for diagnosis of impaired fasting glucose (Early Bird 52)

OBJECTIVE

An HbA1c threshold of ≥ 6.5% has recently been adopted for the diagnosis of diabetes in adults, and of ≥ 5.7% to identify adults at risk. Little,however, is known of HbA1c's behaviour or diagnostic value in youth. Our aim was to describe the course of HbA1c during childhood, and its association with fasting glucose.

RESEARCH DESIGN AND METHODS

HbA1c and glucose were measured every year in a cohort of 326 healthy children (162 boys) from 5 to 15 years. Mixed effects modelling was used to establish the determinants of HbA1c and its development over time. ROC analysis was used to determine the diagnostic value of HbA1c in the 55 individuals who showed impaired fasting glucose(IFG – glucose ≥ 5.6 mmol/L).

RESULTS

Glucose rose progressively from 4.3 mmol/L at 5 years to 5.1 mmol/Lat 15 years, and although there were positive associations between HbA1c and glucose, from 10 to 13 years, HbA1c fell while glucose continued to rise. IFG developed in 55 children, but HbA1c exceeded 5.7% in only 16 of them. The maximum area under the ROC curve was 0.71 at the age of 14 (p<0.001), and the sensitivity and specificity were optimal at 50 and 80% respectively,corresponding to HbA1c of 5.4%.

CONCLUSIONS

Although HbA1c retains a positive association with glucose throughout childhood, it is weak, and their trends diverge from 10 years,suggesting that factors other than glycaemia systematically influence the variance of HbA1c in youth. These findings therefore limit the interpretation of HbA1c for the diagnosis of IFG during childhood.

How to screen obese children at risk for type 2 diabetes mellitus?

BACKGROUND

Recommended screening to identify children at risk for diabetes and its precursors impaired glucose tolerance (IGT) and insulin resistance (IR) is fasted plasma glucose (FPG). This study evaluates the added value of fasted plasma insulin (FPI).

METHODS

This study analyzed routinely collected data of an oral glucose tolerance test (OGTT) of 311 obese children (age 10.8 ± 3.2 years). Diabetes and IGT were defined according to the American Diabetes Association criteria, IR as homeostasis model assessment (HOMA)-IR ≥3.4.

RESULTS

Cases diagnosed with an OGTT if FPG ≥5.6 mmol/L, compared with an OGTT performed if FPG ≥5.6 mmol/L or HOMA-IR ≥3.4, were, respectively, 4 (80%) versus 5 (100%) with diabetes, 7 (28%) versus 16 (64%) with IGT, and 0 (0%) versus 93 (100%) with IR.

CONCLUSIONS

Screening with FPG and FPI has equal burden compared with screening with FPG alone, identifies all patients with diabetes, and identifies more patients with precursors of diabetes.

Variability between self-reported diabetes and measured glucose among health screening participants in South Central Kentucky

AIMS

To assess self-reported diabetes and random glucose among health screening participants and examine factors associated with these two diabetes outcomes.

METHODS

Study subjects were adults aged ≥18 years who participated in diabetes screenings via a mobile health clinic operated by the Institute for Rural Health at Western Kentucky University from 2006 to 2011. Data on self-reported diabetes were based on physicians' past diagnosis. Random plasma glucose was obtained during the screenings. Non-fasting plasma glucose levels of ≥180mg/dl and ≥140mg/dl were used as cutoffs to determine diabetes and diabetes or pre-diabetes, respectively. Logistic regression was used to examine factors associated with self-reported diabetes and elevated non-fasting glucose levels controlling for comorbidities and sociodemographic factors.

RESULTS

The proportion of self-reported diabetes was 9.6%. The proportion of participants with ≥180mg/dl was 3.2% and that with ≥140mg/dl was 7.4%. Odds ratios indicated that self-reported diabetes was higher in older and obese groups and those who had hypertension and hypercholesterolemia and family history of diabetes, while elevated non-fasting glucose levels were higher among participants without health insurance and those who reported they had diabetes.

CONCLUSIONS

Variability in risks between self-reported diabetes and measured glucose should be incorporated in diabetes self-care.

Screening practices for identifying type 2 diabetes in adolescents

OBJECTIVE

To characterize pediatrician and family physician (FP) screening practices for type 2 diabetes among adolescents and to examine the impact of the 2010 American Diabetes Association (ADA) guidelines, recommending use of Hemoglobin A1c (HbA1c).

METHODS

We conducted a cross-sectional mail survey of a random sample of 1,400 U.S. pediatricians and FPs and we received 604 eligible responses. Our main outcome measure was the types of tests ordered by physicians, particularly HbA1c, when presented with a hypothetical scenario.

RESULTS

The overall response rate was 52% (57% for pediatricians and 48% for FPs). Fasting glucose and HbA1c were the most commonly ordered tests. Overall, at least 58% of physicians ordered HbA1c; 35% ordered HbA1c in conjunction with fasting tests; and 22% ordered HbA1c alone or with nonfasting tests. Only 38% of providers were aware of the new ADA recommended HbA1c screening guidelines. However, a majority (67%) said they would change their screening practices. In the context of the guidelines, 84% of physicians would now order HbA1c. Furthermore, there was a large increase in the proportion of physicians who would shift to using HbA1c only or with other nonfasting tests.

CONCLUSIONS

When screening adolescents for type 2 diabetes, providers are more likely to order HbA1c and order fewer fasting tests in response to the new ADA guidelines. HbA1c has lower sensitivity and higher costs than other testing modalities in children, therefore increasing uptake of this test (HbA1c) in children may have implications for both detection rates and healthcare costs.

Use of glycosylated hemoglobin increases diabetes screening for at-risk adolescents in primary care settings

OBJECTIVE

To examine rates of diabetes screening in obese adolescents in an ethnically diverse primary care health care system before and after an internal recommendation to use HbA1c-based screening.

RESEARCH DESIGN AND METHODS

Adolescents 12-18-years old with BMI > 95% were identified through electronic medical record review during two 18-month periods in 8 community health clinics and 13 school-based health centers: period 1 (P1, 19 April 2008 to 19 October 2009) and period 2 (P2, 3 May 2010 to 3 November 2011). Testing for diabetes in the 2 yr preceding the most recently elevated BMI was reviewed.

RESULTS

A total of 2870 obese adolescents were identified in P1 and 3940 in P2. Ethnicity was primarily Hispanic, with smaller populations of Black and White youth. The percent of obese teens screened for diabetes increased from 40% in P1 to 47% in P2. Use of HbA1c increased 493% during P2. Older teens (>15 yr), those seen during P2, and those with BMI ≥ 30 kg/m2 were more likely to be screened. Record review confirmed equal rates of type 2 diabetes in the two periods: 8 incident (0.7%) cases in P1 and 13 (0.7%) in P2.

CONCLUSIONS

The use of HbA1c, a non-fasting and logistically simpler test, was associated with increased diabetes screening in primary care. The percentage of screened patients with confirmed type 2 diabetes remained unchanged. Thus, despite potential pitfalls, the use of HbA1c for screening appears to be as successful as previous approaches in identifying adolescents with diabetes.

Improving screening for cystic fibrosis-related diabetes at a pediatric cystic fibrosis program

OBJECTIVE

Despite guidelines recommending an annual oral glucose tolerance test (OGTT) for all patients with cystic fibrosis (CF) aged ≥ 10 years, screening rates for cystic fibrosis-related diabetes (CFRD) remained low at our center. The aim of this project was to implement an outpatient system to provide effective, evidence-based screening for CFRD at a pediatric CF program.

METHODS

Development of a system to improve outpatient screening for CFRD included structured education, communication with families, and processes for scheduling laboratory appointments. The primary outcome measure was the proportion of eligible patients seen at the clinic who received an OGTT by the subsequent clinic appointment. The proportion of patients without CFRD in our program who received an OGTT within the previous 12 months was also tracked longitudinally.

RESULTS

The outpatient screening rate for CFRD increased from 2% of eligible patients seen at the clinic during the 18 weeks before the start of our initiative to 78% during the 18 weeks after the start of our initiative (P < .001). The screening rate was also increased from the corresponding date range the previous year, when only 35% of eligible patients received an OGTT (P < .001). The overall percentage of patients without CFRD in our program who received an OGTT in the previous 12 months increased from 47% to 71% after implementation of our initiative (P = .003).

CONCLUSIONS

A systematic, quality improvement approach effectively increased the rate of outpatient screening for CFRD at a pediatric CF program.

Prognostic accuracy of continuous glucose monitoring in the prediction of diabetes mellitus in children with incidental hyperglycemia: receiver operating characteristic analysis

AIM

The purpose of this study is to evaluate continuous glucose monitoring (CGM) in predicting diabetes mellitus in children with incident hyperglycemia (IH) and negativity for some insular autoantibodies.

SUBJECTS AND METHODS

Thirty-one autoantibody-negative children who presented at our center with IH underwent a baseline assessment and were followed up for 23.8 months (range, 6-48 months). At the end of the follow-up, we compared the receiver operating characteristic (ROC) areas under the curve (AUCs) of metabolic markers from 17 children who developed diabetes (Group A; n=17) and 14 children who did not develop diabetes (Group B; n=14).

RESULTS

Only two oral glucose tolerance test (OGTT)-derived markers and three CGM-derived markers showed a good prognostic performance, with ROC AUCs indicating significant results (P<0.0001) for the following markers: 2-h glucose, OGTT (0.813; 95% confidence interval [CI] 0.621-0.954); AUC glucose, OGTT (0.832; 95% CI 0.611-0.950); CGM glucose measurement peak (0.803; 95% CI 0.621-0.923); percentage of CGM glucose measurements inside the range 70-125 mg/dL (0.866; 95% CI 0.695-0.961); and percentage of CGM measurements ≥126 mg/dL (0.889; 95% CI 0.724-0.973). The combination of the OGTT-derived markers did not increase the predictive value, but the combination of CGM markers with each other or with the OGTT markers yielded higher ROC AUCs (ranging from 0.828 to 0.945).

CONCLUSIONS

This is the first study showing that CGM is useful in predicting diabetes mellitus in children with IH.

Are the ADA hemoglobin A(1c) criteria relevant for the diagnosis of type 2 diabetes in youth?

Diagnostic criteria for diabetes in children have not been established with nearly the rigor as that employed in adults. Recently revised American Diabetes Association (ADA) criteria allowed utilization of hemoglobin A(1c) (HbA1c) ≥ 6.5 % for diagnosis of diabetes. A recent series of pediatric studies appear to show that HbA1c has lower sensitivity than Fasting plasma glucose (FPG) or oral glucose tolerance test (OGTT). However, FPG and OGTT have themselves never been validated in children. Studies to validate diagnostic thresholds in children appear unlikely to take place. Thus, accepting the major ADA diagnostic criteria appears to be the best course of action for the pediatric community. One area in which correlation studies between HbA1c and FPG or OGTT might shed light is in the definition of criteria for intervention in 'pre-diabetes,' as the Diabetes Prevention Program Trial did not use HbA1c. However, such treatment, and the exact diagnostic thresholds at which it should be initiated in children, remains unproven.

Cost-effectiveness of screening strategies for identifying pediatric diabetes mellitus and dysglycemia

OBJECTIVE

To conduct a cost-effectiveness analysis of screening strategies for identifying children with type 2 diabetes mellitus and dysglycemia (prediabetes/diabetes).

DESIGN

Cost simulation study.

SETTING

A one-time US screening program.

STUDY PARTICIPANTS

A total of 2.5 million children aged 10 to 17 years.

INTERVENTION

Screening strategies for identifying diabetes and dysglycemia.

MAIN OUTCOME MEASURES

Effectiveness (proportion of cases identified), total costs (direct and indirect), and efficiency (cost per case identified) of each screening strategy based on test performance data from a pediatric cohort and cost data from Medicare and the US Bureau of Labor Statistics.

RESULTS

In the base-case model, 500 and 400 000 US adolescents had diabetes and dysglycemia, respectively. For diabetes, the cost per case was extremely high ($312 000-$831 000 per case identified) because of the low prevalence of disease. For dysglycemia, the cost per case was in a more reasonable range. For dysglycemia, preferred strategies were the 2-hour oral glucose tolerance test (100% effectiveness; $390 per case), 1-hour glucose challenge test (63% effectiveness; $571), random glucose test (55% effectiveness; $498), or a hemoglobin A1c threshold of 5.5% (45% effectiveness; $763). Hemoglobin A1c thresholds of 5.7% and 6.5% were the least effective and least efficient (ranges, 7%-32% and $938-$3370) of all strategies evaluated. Sensitivity analyses for diabetes revealed that disease prevalence was a major driver of cost-effectiveness. Sensitivity analyses for dysglycemia did not lead to appreciable changes in overall rankings among tests.

CONCLUSIONS

For diabetes, the cost per case is extremely high because of the low prevalence of the disease in the pediatric population. Screening for diabetes could become more cost-effective if dysglycemia is explicitly considered as a screening outcome.

A risk score for identifying overweight adolescents with dysglycemia in primary care settings

OBJECTIVE

To develop a clinical risk scoring system for identifying adolescents with dysglycemia (prediabetes or diabetes) who need further confirmatory testing and to determine whether the addition of non-fasting tests would improve the prediction of dysglycemia.

STUDY DESIGN

A sample of 176 overweight and obese adolescents (10-17 years) had a history/physical exam, a 2-h oral glucose tolerance test, and non-fasting tests [hemoglobin A1c, 1-h glucose challenge test (GCT), and random glucose test] performed. Given the low number of children with diabetes, we created several risk scoring systems combining the clinical characteristics with non-fasting tests for identifying adolescents with dysglycemia and compared the test performance.

RESULTS

Sixty percent of participants were white and 32% were black; 39.2% had prediabetes and 1.1% had diabetes. A basic model including demographics, body mass index percentile, family history of diabetes, and acanthosis nigricans had reasonable test performance [area under the curve (AUC), 0.75; 95% confidence interval (95% CI), 0.68-0.82]. The addition of random glucose (AUC, 0.81; 95% CI, 0.75-0.87) or 1-h GCT (AUC, 0.82; 95% CI, 0.75-0.88) to the basic model significantly improved the predictive capacity, but the addition of hemoglobin A1c did not (AUC, 0.76; 95% CI, 0.68-0.83). The clinical score thresholds to consider for the basic plus random glucose model are total score cutoffs of 60 or 65 (sensitivity 86% and 65% and specificity 60% and 78%, respectively) and for the basic plus 1-h GCT model are total score cutoffs of 50 or 55 (sensitivity 87% and 73% and specificity 59% and 76%, respectively).

CONCLUSIONS

Pending a validation in additional populations, a risk score combining the clinical characteristics with non-fasting test results may be a useful tool for identifying children with dysglycemia in the primary care setting.

Hemoglobin A1c measurement for the diagnosis of Type 2 diabetes in children

Laboratory measurements of hemoglobin A1c above 6.5% were approved as an additional diagnostic criteria for diabetes mellitus by the American Diabetes Association in 2010. Several recent pediatric studies have cast HbA1c measurement in children in an unfavorable light in the pediatric population, by comparing HbA1c measurements to results on oral glucose tolerance test (OGTT) or fasting plasma glucose (FPG). However, many of these studies do not recognize that diabetes diagnostic criteria are based upon long-term health outcomes. In this sense, OGTT and FPG have themselves never been validated in the pediatric population. Studies to validate diagnostic tests for diabetes in pediatric populations may take a substantial period of time, and may prove unfeasible. However, studies that tie diagnostic results as a child to diagnostic results as an adult may be more feasible and may provide the data needed to determine which pediatric diagnostic criteria to use. Thus, for the time being, except for cases of hemoglobinopathy, cystic fibrosis, and a few other exceptions, describing HbA1c as ‘lacking in sensitivity or specificity’ in the pediatric population because of lack of correlation with OGTT is not scientifically sound.

HbA(1c) diagnostic categories and β-cell function relative to insulin sensitivity in overweight/obese adolescents

OBJECTIVE

The recommended HbA(1c) diagnostic categories remain controversial and their utility in doubt in pediatrics. We hypothesized that alterations in the pathophysiologic mechanisms of type 2 diabetes may be evident in the American Diabetes Association recommended at-risk/prediabetes category (HbA(1c) 5.7 to <6.5%).

RESEARCH DESIGN AND METHODS

We compared in vivo hepatic and peripheral insulin sensitivity by [6,6-(2)H(2)] glucose and a 3-h hyperinsulinemic-euglycemic clamp and β-cell function by a 2-h hyperglycemic clamp (∼225 mg/dL) in overweight/obese (BMI ≥85th percentile) adolescents with prediabetes (HbA(1c) 5.7 to <6.5%) (n = 160) to those with normal HbA(1c) (<5.7%) (n = 44). β-Cell function was expressed relative to insulin sensitivity (i.e., the disposition index = insulin sensitivity × first-phase insulin).

RESULTS

In the prediabetes versus normal HbA(1c) category, fasting glucose, insulin, and oral glucose tolerance test (OGTT) area under the curve for glucose and insulin were significantly higher; hepatic and peripheral insulin sensitivity were lower; and β-cell function relative to insulin sensitivity was lower (366 ± 48 vs. 524 ± 25 mg/kg/min; P = 0.005). A total of 27% of youth in the normal HbA(1c) category and 41% in the prediabetes HbA(1c) category had dysglycemia (impaired fasting glucose and/or impaired glucose tolerance) by a 2-h OGTT.

CONCLUSIONS

Overweight/obese adolescents with HbA(1c) in the at-risk/prediabetes category demonstrate impaired β-cell function relative to insulin sensitivity, a metabolic marker for heightened risk of type 2 diabetes. Thus, HbA(1c) may be a suitable screening tool in large-scale epidemiological observational and/or interventional studies examining the progression or reversal of type 2 diabetes risk.

Insulin resistance in type 2 diabetic youth

PURPOSE OF REVIEW

This review focuses on recent literature on insulin resistance in youth with type 2 diabetes mellitus (T2DM). Insulin resistance is associated with a variety of cardiometabolic problems leading to increased morbidity and mortality across the lifespan.

RECENT FINDINGS

Functional pancreatic β-cell changes play a role in the transition from obesity to impaired glucose tolerance (IGT). Insulin resistance drives islet cell upregulation, manifested by elevated glucagon and c-peptide levels, early in the transition to IGT. Surrogate measurements of insulin resistance and insulin secretion exist but their accuracy compared to clamp data is imperfect. Recent large longitudinal studies provide detailed information on the progression from normoglycemia to T2DM and on the phenotype of T2DM youth. Defining prediabetes and T2DM remains a challenge in youth. Lifestyle interventions do not appear as effective in children as in adults. Metformin remains the only oral hypoglycemic agent approved for T2DM in youth.

SUMMARY

New insights exist regarding the conversion from insulin resistance to T2DM, measurement of insulin resistance and phenotypes of insulin resistance youth, but more information is needed. Surrogate measurements of insulin resistance, additional treatment options for insulin resistance and individualization of treatment options for T2DM adolescents in particular require further investigation.

Use of HbA(1C) testing to diagnose pre-diabetes in high risk African American children: a comparison with fasting glucose and HOMA-IR

OBJECTIVE

This study aimed to compare the discriminating power of HbA(1C) with other pre-diabetes diagnostic tests specifically in high-risk African American children.

RESEARCH DESIGN AND METHODS

A cross-sectional analysis was performed on a sample of 172 children (70 boys and 102 girls) aged 9-11 years with BMI's above the 85th percentile. Fasting glucose, insulin and HbA(1C) were analyzed from the plasma samples.

RESULTS

Of the 172 participants included in this analysis, 21 (12.2%) had HbA(1C) concentrations above the cutoff of 5.7 used to identify pre-diabetes. None (0%) of these 21 participants, however, were observed to have a glucose concentration above the pre-diabetes cutoff of 110 mg/dl, and only 13 of 21 participants had HOMA-IR above the pre-diabetes cutoff of 2.5. When compared to the previously identified glucose cutoff of 110 mg/dl and HOMA-IR cutoff of 2.5 for pre-diabetes, HbA(1C) showed high specificity (88 and 93%, respectively) but very low sensitivity (0 and 21%, respectively). Glucose, insulin and HOMA-IR were significantly interrelated, but HbA(1C) was not significantly correlated with these biochemical prediabetes assessment variables, nor with anthropometric (BMIz, WC) risk factors.

CONCLUSION

Our results suggest that HbA(1C) had poor discrimination power to identify prediabetes in overweight and obese 9- to 11-year-old African American children. Future studies are recommended to compare the feasibility, sensitivity and predictive power of different screening tests currently recommended to avoid inadequacy when screening for prediabetes and diabetes.