Implications of using hemoglobin A1C for diagnosing diabetes mellitus

Prevalence of Diabetes by BMI: China Nutrition and Health Surveillance (2015-2017) and U.S. National Health and Nutrition Examination Survey (2015-2018)

Introduction

The risk of diabetes begins at a lower BMI among Asian adults. This study compares the prevalence of diabetes between the U.S. and China by BMI.

Methods

Data from the 2015-2017 China Nutrition and Health Surveillance (n=176,223) and the 2015-2018 U.S. National Health and Nutrition Examination Survey (n=4,464) were used. Diagnosed diabetes was self-reported. Undiagnosed diabetes was no report of diagnosed diabetes and fasting plasma glucose ≥126 mg/dL or HbA1c ≥6.5%. Predicted age-adjusted prevalence estimates by BMI were produced using sex- and country-specific logistic regression models.

Results

In China, the age-adjusted prevalence of total diabetes was 7.8% (95% CI=7.4%, 8.3%), lower than the 14.6% (95% CI=13.1%, 16.3%) in the U.S. The prevalence of diagnosed diabetes was also lower in China than in the U.S. There were no statistically significant differences in the prevalence of undiagnosed diabetes between China and the U.S. The distribution of BMI in China was lower than in the U.S., and the predicted prevalence of total diabetes was similar between China and the U.S. when comparing adults with the same BMI. The predicted prevalence of undiagnosed diabetes was higher in China than in the U.S. for both men and women, and this disparity increased with BMI. When comparing adults at the same BMI, there was little difference in the prevalence of total diabetes, but diagnosed diabetes was lower in China than in the U.S., and undiagnosed was higher.

Conclusions

Although differences in BMI appear to explain nearly all of the differences in total diabetes prevalence in the 2 countries, not all factors that are associated with diabetes risk have been investigated.

Correlation between whole salivary prostaglandin E2 and hemoglobin A1c levels among type-2 diabetic and non-diabetic patients with periodontal inflammation

BACKGROUND

It is hypothesized that whole salivary prostaglandin E2 (PgE2) levels are higher in patients with type-2 diabetes mellitus (type-2 DM) than non-diabetic individuals with periodontal inflammation; and that whole salivary expression of PgE2 is correlated with hemoglobin A1C (HbA1c) levels. The aim of the present study was to compare whole salivary PgE2 levels among patients with type-2 DM and non-diabetic individuals with periodontal inflammation.

METHODS

Sociodemographic data, duration since the diagnosis and management of type-2 DM, most recent hemoglobin A1C (HbA1c level), and any familial history of DM was retrieved from patient's healthcare records. Participants were divided into four groups: Group-1: type-2 diabetics with periodontal inflammation; Group-2: type-2 diabetics without periodontal inflammation; Group-3: non-diabetics with periodontal inflammation; and Group-4: non-diabetics without periodontal inflammation. Plaque and gingival indices (PI and GI), probing depth (PD), clinical attachment loss (CAL) and marginal bone loss (MBL) were measured. Unstimulated whole saliva samples were collected and PgE2 levels were measured. Group-comparisons were done and P < 0.05 were considered statistically significant.

RESULTS

One-hundred-sixty individuals were included. Mean HbA1c levels were higher in Group-1 than groups 2 (P < 0.05), 3 (P < 0.05) and 4 (P < 0.05). The PI (P < 0.05), GI (P < 0.05) and PD (P < 0.05) were higher in Group-1 than groups 2 and 4. The CAL was higher in Group-1 than groups 2 (P < 0.05) and 3 (P < 0.05). The PD (P < 0.05), PI (P < 0.05) and GI (P < 0.05) were higher in Group-3 than Group-4. The MBL was higher in Group-1 than groups 2 (P < 0.05), 3 (P < 0.05) and 4 (P < 0.05). The PgE2 levels were higher in Group-1 than groups 2 (P < 0.05), 3 (P < 0.05) and 4 (P < 0.05).

CONCLUSION

Hyperglycemia in patients with type-2 DM is associated with increased expression of whole salivary PgE2 levels and worsened periodontal inflammation compared with individuals with well-controlled type-2 DM and non-diabetic individuals.

Future is Brighter: New Potential Paradigm-Shifting Medications and Regimens for Diabetes and Obesity

Diabetes is a chronic illness that can become debilitating owing to its microvascular and macrovascular complications. Its prevalence is increasing and so is its cost. Diabetes, particularly type 2, appears to have a very close relationship with obesity. While lifestyle modifications, exercises, and current therapeutics have substantially improved clinical outcomes, the need for new therapeutics and regimens continue to exist. Several new medications and regimens for diabetes, obesity, and diabesity are showing promising results in advanced clinical trials. For type 1 diabetes mellitus (T1DM), they include teplizumab, ustekinumab, jakinibs, and cell therapies, whereas for type 2 diabetes mellitus (T2DM), they include once-weakly insulin, tirzepatide, high oral dose of semaglutide, orforglipron, retatrutide, CagriSema, and survodutide. Given their structural and mechanistic diversity as well as their substantial efficacy and safety profiles, these medications and regimens are paradigm shifting and promise a brighter future. They will likely enable better disease prevention and management. This review will provide details about each of the above strategies to keep the scientific community up to date about progress in the fields of diabetes and obesity.

Global trend analysis of diabetes mellitus incidence, mortality, and mortality-to-incidence ratio from 1990 to 2019

Diabetes Mellitus (DM) is a common chronic disease and a public health challenge worldwide. The present study aimed to analyze the trend in DM incidence, mortality, and mortality-to-incidence ratio (MIR) world over 30 years. The age-standardized DM incidence and mortality rates for both genders and different countries of the world from 1990 to 2019 were extracted from the Global Burden of Disease (GBD) study and the Human Development Index (HDI) was obtained for all countries from the United Nations Development Program (UNDP) database. The mean trends for the indicators for developing countries, developed countries, and all countries were evaluated using Generalized Estimating Equations (GEE) and the spline model. The estimates showed that the global mean trend of DM incidence from 1990 to 2019 followed an upward trend with an annual increase of 3.73 cases per 100,000 people. The global mean of DM mortality followed an upward trend with an annual increase of 0.43 cases until 2005 followed by a downward trend after this year with an annual decrease of 0.14 and the global mean MIR followed a downward trend during the same period with an annual decrease of 0.001 per 100,000 people. Besides, the mean incidence of DM in developing countries followed an upward trend similar to the trend in developed countries. Additionally, the mean mortality rate due to DM in developing countries increased with a slope of 0.62 until 2005 and then decreased with a slope of 0.02, and the mean MIR trend in the developed and developing countries showed a downward trend. Thus, developed countries followed a relatively faster decrease in MIR than developing countries.The data from the present study show the increased incidence of DM has made it one of the most important health concerns in the world, and if this issue is not addressed, this disease can cause more concerns for communities in the coming years. This being so, more DM prevention and control programs need to be put into practice.

Clinical application guidelines for blood glucose monitoring in China (2022 edition)

Glucose monitoring is an important component of diabetes management. The Chinese Diabetes Society (CDS) has been producing evidence-based guidelines on the optimal use of glucose monitoring since 2011. In recent years, new technologies in glucose monitoring and more clinical evidence, especially those derived from Chinese populations, have emerged. In this context, the CDS organised experts to revise the Clinical application guidelines for blood glucose monitoring in China in 2021. In this guideline, we focus on four methods of glucose monitoring that are commonly used in clinical practice, including capillary glucose monitoring, glycated haemoglobin A1c, glycated albumin, and continuous glucose monitoring. We describe the definitions and technical characteristics of these methods, the factor that may interfere with the measurement, the advantages and caveats in clinical practice, the interpretation of glucose metrics, and the relevant supporting evidence. The recommendations for the use of these methods are also provided. The various methods of glucose monitoring have their strengths and limitations and cannot be replaced by one another. We hope that these guidelines could aid in the optimal application of common methods of glucose monitoring in clinical practice for better diabetes care.

Trends in all-cause mortality among people with diagnosed diabetes in high-income settings: a multicountry analysis of aggregate data

BACKGROUND

Population-level trends in mortality among people with diabetes are inadequately described. We aimed to examine the magnitude and trends in excess all-cause mortality in people with diabetes.

METHODS

In this retrospective, multicountry analysis, we collected aggregate data from 19 data sources in 16 high-income countries or jurisdictions (in six data sources in Asia, eight in Europe, one from Australia, and four from North America) for the period from Jan 1, 1995, to Dec 31, 2016, (or a subset of this period) on all-cause mortality in people with diagnosed total or type 2 diabetes. We collected data from administrative sources, health insurance records, registries, and a health survey. We estimated excess mortality using the standardised mortality ratio (SMR).

FINDINGS

In our dataset, there were approximately 21 million deaths during 0·5 billion person-years of follow-up among people with diagnosed diabetes. 17 of 19 data sources showed decreases in the age-standardised and sex-standardised mortality in people with diabetes, among which the annual percentage change in mortality ranged from -0·5% (95% CI -0·7 to -0·3) in Hungary to -4·2% (-4·3 to -4·1) in Hong Kong. The largest decreases in mortality were observed in east and southeast Asia, with a change of -4·2% (95% CI -4·3 to -4·1) in Hong Kong, -4·0% (-4·8 to -3·2) in South Korea, -3·5% (-4·0 to -3·0) in Taiwan, and -3·6% (-4·2 to -2·9) in Singapore. The annual estimated change in SMR between people with and without diabetes ranged from -3·0% (95% CI -3·0 to -2·9; US Medicare) to 1·6% (1·4 to 1·7; Lombardy, Italy). Among the 17 data sources with decreasing mortality among people with diabetes, we found a significant SMR increase in five data sources, no significant SMR change in four data sources, and a significant SMR decrease in eight data sources.

INTERPRETATION

All-cause mortality in diabetes has decreased in most of the high-income countries we assessed. In eight of 19 data sources analysed, mortality decreased more rapidly in people with diabetes than in those without diabetes. Further longevity gains will require continued improvement in prevention and management of diabetes.

FUNDING

US Centers for Disease Control and Prevention, Diabetes Australia Research Program, and Victoria State Government Operational Infrastructure Support Program.

Metabolomics of various samples advancing biomarker discovery and pathogenesis elucidation for diabetic retinopathy

Diabetic retinopathy (DR) is a universal microvascular complication of diabetes mellitus (DM), which is the main reason for global sight damage/loss in middle-aged and/or older people. Current clinical analyses, like hemoglobin A1c, possess some importance as prognostic indicators for DR severity, but no effective circulating biomarkers are used for DR in the clinic currently, and studies on the latent pathophysiology remain lacking. Recent developments in omics, especially metabolomics, continue to disclose novel potential biomarkers in several fields, including but not limited to DR. Therefore, based on the overview of metabolomics, we reviewed progress in analytical technology of metabolomics, the prominent roles and the current status of biomarkers in DR, and the update of potential biomarkers in various DR-related samples via metabolomics, including tear as well as vitreous humor, aqueous humor, retina, plasma, serum, cerebrospinal fluid, urine, and feces. In this review, we underscored the in-depth analysis and elucidation of the common biomarkers in different biological samples based on integrated results, namely, alanine, lactate, and glutamine. Alanine may participate in and regulate glucose metabolism through stimulating N-methyl-D-aspartate receptors and subsequently suppressing insulin secretion, which is the potential pathogenesis of DR. Abnormal lactate could cause extensive oxidative stress and neuroinflammation, eventually leading to retinal hypoxia and metabolic dysfunction; on the other hand, high-level lactate may damage the structure and function of the retinal endothelial cell barrier via the G protein-coupled receptor 81. Abnormal glutamine indicates a disturbance of glutamate recycling, which may affect the activation of Müller cells and proliferation via the PPP1CA-YAP-GS-Gln-mTORC1 pathway.

Emerging Diabetic Novel Biomarkers of the 21st Century

Diabetes is a growing epidemic with estimated prevalence of infected to reach ~592 million by the year 2035. An effective way to approach is to detect the disease at a very early stage to reduce the complications and improve lifestyle management. Although several traditional biomarkers including glucated hemoglobin, glucated albumin, fructosamine, and 1,5-anhydroglucitol have helped in ease of diagnosis, there is lack of sensitivity and specificity and are inaccurate in certain clinical settings. Thus, search for new and effective biomarkers is a continuous process with an aim of accurate and timely diagnosis. Several novel biomarkers have surged in the present century that are helpful in timely detection of the disease condition. Although it is accepted that a single biomarker will have its inherent limitations, combining several markers will help to identify individuals at high risk of developing prediabetes and eventually its progression to frank diabetes. This review describes the novel biomarkers of the 21st century, both in type 1 and type 2 diabetes mellitus, and their present potential for assessing risk stratification due to insulin resistance that will pave the way for improved clinical outcome.

Time trends in the incidence of clinically diagnosed type 2 diabetes and pre-diabetes in the UK 2009-2018: a retrospective cohort study

INTRODUCTION

To describe recent trends in the incidence of clinically diagnosed type 2 diabetes and pre-diabetes in people seen in UK general practice.

RESEARCH DESIGN AND METHODS

A retrospective cohort study using IQVIA Medical Research Data looking at people newly diagnosed with type 2 diabetes and pre-diabetes through primary care registers in the UK between 1 January 2009 and 31 December 2018.

RESULTS

A cohort of 426 717 people were clinically diagnosed with type 2 diabetes and 418 656 people met the criteria for a diagnosis of pre-diabetes in that time period. The incidence of clinically diagnosed type 2 diabetes per 1000 person years at risk (PYAR) in men decreased from a peak of 5.06 per 1000 PYAR (95% CI 4.97 to 5.15) in 2013 to 3.56 per 1000 PYAR (95% CI 3.46 to 3.66) by 2018. For women, the incidence of clinically diagnosed type 2 diabetes per 1000 PYAR decreased from 4.45 (95% CI 4.37 to 4.54) in 2013 to 2.85 (2.76 to 2.93) in 2018. The incidence rate of pre-diabetes tripled by the end of the same study period in men and women.

CONCLUSIONS

Between 2009 and 2018, the incidence rate of new clinical diagnoses of type 2 diabetes recorded in a UK primary care database decreased by a third from its peak in 2013-2014, while the incidence of pre-diabetes has tripled. The implications of this on timely treatment, complication rates and mortality need further longer term exploration.

Predictors of mortality in a multiracial urban cohort of persons with type 2 diabetes and novel coronavirus 19

BACKGROUND

Diabetes has been identified as a risk factor for intubation and mortality in patients with coronavirus disease 2019 (COVID-19), caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We seek to examine the impact of clinical variables such as glycosylated hemoglobin (HbA1c) on mortality and need for intubation, as well as demographic variables such as age, sex, and race on persons with type 2 diabetes and COVID-19.

METHODS

Analyses were conducted on 4413 patients with an International Classification of Diseases and Related Health Problems (ICD-10) diagnosis of type 2 diabetes and COVID-19. Survival analysis was conducted using Kaplan-Meier curves and the log-rank test to compare subgroup analyses.

RESULTS

In this multivariate analysis, male gender, older age, and hyperglycemia at admission were associated with increased mortality and intubation, but this was not seen for race, ethnicity, insurance type, or HbA1c. Based on Kaplan-Meier analysis, having comorbid conditions such as hypertension, chronic kidney disease, and coronary artery disease was associated with a statistically significant increased risk of mortality.

CONCLUSIONS

Glycemic levels at admission have a greater impact on health outcomes than HbA1c. Older men and those with comorbid disease are also at greater risk for mortality. Further longitudinal studies need to be done to evaluate the impact of COVID-19 on type 2 diabetes.

The MEDGICarb-Study: Design of a multi-center randomized controlled trial to determine the differential health-promoting effects of low- and high-glycemic index Mediterranean-style eating patterns

Adults with central adiposity and other features of the metabolic syndrome have a markedly elevated risk of developing type 2 diabetes (T2D) and cardiovascular disease (CVD). A Mediterranean-style healthy eating pattern (MED-HEP) and consumption of foods with a lower glycemic index (GI) are potential dietary approaches to curb the T2D and CVD epidemic. However, experimental evidence of the effectiveness of MED-HEP and of the contribution of GI towards improving indices of glucose homeostasis, especially among non-diabetic people, are lacking. Therefore, we developed the MedGI-Carb trial, a multi-center (Italy, Sweden, and United States) intervention in adults with at least two components of the metabolic syndrome (elevated waist circumference + one other component) that aims to improve markers of glucose homeostasis through dietary modification. All participants were randomized to consume an isocaloric high- or low-GI MED-HEP for 12 weeks. We hypothesized that indexes of insulinemia (primary outcome: postprandial insulin and glucose after standardized breakfast and lunch; secondary outcomes: fasting plasma glucose and insulin, HbA_1c, 24-h continuous glucose monitoring) would be improved more with the low-GI versus the high-GI MED-HEP. Additionally, we hypothesized that consumption of a MED-HEP would improve other markers of cardiometabolic health and well-being (fasting blood pressure, fasting lipid profile, sleep quality, satiety, global metabolic alterations in the plasma metabolome, changes in the gut microbiota, subjective health and well-being), with no difference between groups. Collectively, the design of MEDGI-Carb allows several different research questions to be explored. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03410719.

A systematic review of trends in all-cause mortality among people with diabetes

AIMS/HYPOTHESIS

We examined all-cause mortality trends in people with diabetes and compared them with trends among people without diabetes.

METHODS

MEDLINE, EMBASE and CINAHL databases were searched for observational studies published from 1980 to 2019 reporting all-cause mortality rates across ≥2 time periods in people with diabetes. Mortality trends were examined by ethnicity, age and sex within comparable calendar periods.

RESULTS

Of 30,295 abstracts screened, 35 studies were included, providing data on 69 separate ethnic-specific or sex-specific populations with diabetes since 1970. Overall, 43% (3/7), 53% (10/19) and 74% (32/43) of the populations studied had decreasing trends in all-cause mortality rates in people with diabetes in 1970-1989, 1990-1999 and 2000-2016, respectively. In 1990-1999 and 2000-2016, mortality rates declined in 75% (9/12) and 78% (28/36) of predominantly Europid populations, and in 14% (1/7) and 57% (4/7) of non-Europid populations, respectively. In 2000-2016, mortality rates declined in 33% (4/12), 65% (11/17), 88% (7/8) and 76% (16/21) of populations aged <40, 40-54, 55-69 and ≥70 years, respectively. Among the 33 populations with separate mortality data for those with and without diabetes, 60% (6/10) of the populations with diabetes in 1990-1999 and 58% (11/19) in 2000-2016 had an annual reduction in mortality rates that was similar to or greater than in those without diabetes.

CONCLUSIONS/INTERPRETATION

All-cause mortality has declined in the majority of predominantly Europid populations with diabetes since 2000, and the magnitude of annual mortality reduction matched or exceeded that observed in people without diabetes in nearly 60% of populations. Patterns of diabetes mortality remain uncertain in younger age groups and non-Europid populations.

REGISTRATION

PROSPERO registration ID CRD42019095974. Graphical abstract.

Helicobacter pylori infection is associated with diabetes among Chinese adults

AIMS/INTRODUCTION

Several epidemiological studies investigated the effect of Helicobacter pylori infection on diabetes, but the conclusions remained inconsistent. We aimed to explore the relationship between H. pylori infection and diabetes, as well as glycemic metabolism profiles.

MATERIALS AND METHODS

A cross-sectional study including 58,482 Chinese adults was carried out between January 2016 and December 2017. H. pylori infection was diagnosed by the 13 C-urea breath test. Multivariate regression analyses were carried out to evaluate the association of H. pylori infection with diabetes.

RESULTS

Of the 58,482 participants, 3,449 (5.9%) had diabetes. The H. pylori-positive participants had a higher rate of diabetes (7.3% vs 5.2%, P < 0.001), and higher levels of fasting plasma glucose (5.36 ± 1.12 mmol/L vs 5.28 ± 0.95 mmol/L, P < 0.001) and glycated hemoglobin A1c (5.63 ± 0.68% vs 5.57 ± 0.60%, P < 0.001) than the H. pylori negative group. Multivariate regression analyses showed that H. pylori infection was positively related to diabetes (odds ratio 1.25, 95% confidence interval 1.15-1.35). Among the H. pylori-positive participants, the elevated levels of fasting plasma glucose and glycated hemoglobin A1c were 0.033 mmol/L (95% confidence interval 0.016-0.049 mmol/L) and 0.024% (95% confidence interval 0.008-0.041%), respectively. Additionally, H. pylori infection was significantly related to diabetes in participants aged ≥44 years, but not in participants aged <44 years.

CONCLUSIONS

The present study showed that H. pylori infection is associated with diabetes among Chinese adults. More attention should be paid to adults with H. pylori infection for effective prevention of diabetes.

The risk of type 2 diabetes mellitus according to 2-h plasma glucose level: The Korean Genome and Epidemiology Study (KoGES)

BACKGROUND

Although impaired glucose tolerance (IGT) is a definite risk factor for type 2 diabetes mellitus (T2DM), there is limited information about the risk stratification for incident T2DM within IGT group. Thus, we aimed to evaluate the incidental risk for T2DM according to 2-h plasma glucose (2-h PG) level of oral glucose tolerance test (OGTT) and phenotype of IGT.

METHODS

7654 Korean participated in the Korean Genome and Epidemiology Study (KoGES) were stratified by 2-h PG levels of OGTT, and followed up for 63,665 person-years. Cox proportional hazards model was used to calculate the hazard ratios (HRs) and 95% confidential interval (CI) for T2DM according to 2-h PG levels of OGTT with adjustment for multiple covariates. Subgroup analysis was performed by gender and the presence of impaired fasting glucose (IFG) or not.

RESULTS

Within IGT, the adjusted HRs for T2DM significantly increased proportionally to 2-h PG level [<140mg/dL: reference, 140-159mg/dL: 3.07 (2.67-3.54), 160-179mg/dL: 5.44 (CI 4.66-6.34), 180-199mg/dL: 7.91 (CI 6.53-9.59)]. IGT combined with IFG had the profoundly increased HRs than isolated IFG. Even within normal glucose tolerance (NGT), 2-h PG level≥120mg/dL had the higher risk for T2DM than other NGT groups. These associations were more dominant in male than female.

CONCLUSION

The highest level of 2h-PG (180-199mg/dL) in IGT and IGT with IFG were strong predictor for T2DM. 2-h PG of 120-139mg/dL was more significantly associated with T2DM within NGT, and male was more susceptible for T2DM than female.

Predictive value of fasting blood glucose for serious coronary atherosclerosis in non-diabetic patients

Objective

To determine if high fasting blood glucose (FBG) level is an independent predictor of serious coronary lesions in patients with coronary artery disease (CAD).

Methods

We enrolled 64 patients who had symptoms of chest discomfort and who underwent coronary angiography. FBG was determined from blood samples and the extent of coronary artery lesions was analyzed according to Gensini score. We examined the relationships among diabetes, FBG, and coronary artery severity.

Results

Diabetes and FBG were significantly and positively related to Gensini score. Diabetes, but not FBG, was independently correlated with the occurrence of a Gensini score >41. However, FBG was significantly associated with Gensini score >41 in non-diabetic patients.

Conclusion

Hyperglycemia is an independent predictor of severe CAD in non-diabetic patients. Clinicians should be aware of this and should carry out appropriate early interventions.

Non-communicable disease risk factor profile among public employees in a regional city in northern Ethiopia

The burden of non-communicable diseases (NCDs) is increasing in Ethiopia. This study aims to describe the prevalence of NCD risk factors of public employees in a regional city in northern Ethiopia. We conducted a cross-sectional epidemiological study targeting men and women aged 25-64 years employed by public offices in Mekelle. The prevalence was age-standardized to the Ethiopian 2007 population. Among the 1380 subjects (823 men and 557 women), 68.7% had less than 1 serving of fruits and vegetables per day, 41.0% were physically inactive, and 57.3% observed religious fast. The age-standardised prevalence of abdominal obesity was 29.3% in men and 58.5% in women, but that of metabolic syndrome was comparable between men (39.2%) and women (39.0%). The prevalence of diabetes was underestimated if only fasting blood glucose (FBG) was used for the diagnosis compared to combination of FBG and glycated haemoglobin (HbA1c) (6.7% in men and 3.8% in women vs. 12.1% in men and 5.6% in women). More than a quarter (26.1%) of men and 8.7% of women had estimated 10-year risk of cardiovascular disease of 10% or more. This study revealed the high prevalence of NCD metabolic risk factors among the urban public employees in the highland of Ethiopia.

Hemoglobin A1c and diagnosis of diabetes

The prevalence of diabetes is increasing markedly worldwide, especially in China. Hemoglobin A1c is an indicator of mean blood glucose concentrations and plays an important role in the assessment of glucose control and cardiovascular risk. In 2010, the American Diabetes Association included HbA1c ≥6.5% into the revised criteria for the diagnosis of diabetes. However, the debate as to whether HbA1c should be used to diagnose diabetes is far from being settled and there are still unanswered questions regarding the cut-off value of HbA1c for diabetes diagnosis in different populations and ethnicities. This review briefly introduces the history of HbA1c from discovery to diabetes diagnosis, key steps towards using HbA1c to diagnose diabetes, such as standardization of HbA1c measurements and controversies regarding HbA1c cut-off points, and the performance of HbA1c compared with glucose measurements in the diagnosis of diabetes.

The utility of HbA1c combined with haematocrit for early screening of gestational diabetes mellitus

AIMS

To evaluate the utility of glycated haemoglobin A1c (HbA1c) alone and in combination with haematocrit (HCT) for screening gestational diabetes mellitus (GDM) between 12-16 gestational weeks.

METHODS

This prospective study was carried out in the Obstetrics and Gynaecology Hospital of Fudan University from November 2014 to February 2015. In total, 690 pregnant women between 20 and 35 years old were included in this study. All subjects received a routine blood examination for HbA1c and HCT at 12-16 gestational weeks (gw) and a 75-g oral glucose tolerance test at 24-28 gw. Threshold values for the diagnosis of GDM were a plasma glucose concentration of 5.1 mmol/L after fasting, 10.0 mmol/L at 60 min, and 8.5 mmol/L at 120 min. Receiver operating characteristic curves were used to evaluate the diagnostic performance of HbA1c with or without HCT.

RESULTS

One hundred seven women were diagnosis with GDM at 24-28 gw. An HbA1c cutoff value < 4.55% at 12-16 gw showed adequate sensitivity to exclude GDM (85.0%) but low specificity (17.3%), while an HbA1c cutoff value ≥ 5.25% presented adequate specificity (96.6%) but low sensitivity (13.3%) in diagnosing GDM. The area under the receiver operating characteristic curve for HbA1c (12-16 gw) detection of GDM was 0.563 (95% confidence interval [CI], 0.50-0.625). When combined HbA1c with HCT ( > 38.8%) for the screening of GDM, the area under the receiver operating characteristic curve was 0.604 (95% [CI] 0.509, 0.701).

CONCLUSIONS

Whether the adoption of HbA1c as a screening test for GDM would benefit pregnant women remains to be determined. However, combining HbA1c with HCT for the screening of GDM may be a useful tool to predict GDM.

PREVIEW: Prevention of Diabetes through Lifestyle Intervention and Population Studies in Europe and around the World. Design, Methods, and Baseline Participant Description of an Adult Cohort Enrolled into a Three-Year Randomised Clinical Trial

Type-2 diabetes (T2D) is one of the fastest growing chronic diseases worldwide. The PREVIEW project has been initiated to find the most effective lifestyle (diet and physical activity) for the prevention of T2D, in overweight and obese participants with increased risk for T2D. The study is a three-year multi-centre, 2 × 2 factorial, randomised controlled trial. The impact of a high-protein, low-glycaemic index (GI) vs. moderate protein, moderate-GI diet in combination with moderate or high-intensity physical activity on the incidence of T2D and the related clinical end-points are investigated. The intervention started with a two-month weight reduction using a low-calorie diet, followed by a randomised 34-month weight maintenance phase comprising four treatment arms. Eight intervention centres are participating (Denmark, Finland, United Kingdom, The Netherlands, Spain, Bulgaria, Australia, and New Zealand). Data from blood specimens, urine, faeces, questionnaires, diaries, body composition assessments, and accelerometers are collected at months 0, 2, 6, 12, 18, 24, and 36. In total, 2326 adults were recruited. The mean age was 51.6 (SD 11.6) years, 67% were women. PREVIEW is, to date, the largest multinational trial to address the prevention of T2D in pre-diabetic adults through diet and exercise intervention. Participants will complete the final intervention in March, 2018.

Glycated hemoglobin A1C and vitamin D and their association with diabetic retinopathy severity

OBJECTIVES

This retrospective, population-based, cross-sectional study evaluated the association between vitamin D deficiency and retinopathy severity in diabetic patients with poorly or well controlled glycaemia. Other potential risk factors for diabetic retinopathy severity were also assessed.

METHODS

The National Health and Nutrition Examination Survey (NHANES) 2005-2008 data were used for the study. Outcomes assessed included retinopathy severity, HbA1c levels, socioeconomic, behavioral, and biological factors. Univariate and multivariate regression analysis was used to evaluate association of different parameters with retinopathy severity. The interaction among HbA1c control, vitamin D deficiency, and retinopathy severity were also explored.

RESULTS

The population included 842 adults (52.8% women) with mean age of 61.2 years. Retinopathy was detected in 301 subjects (35.7%). Mild non-proliferative retinopathy (NPR) was present in 195 subjects (23.2%), severe non-proliferative and proliferative retinopathy in 106 subjects (12.6%). Multivariate ordinal regression analysis found being male (odds ratio (OR): 1.602, P=0.001), increased duration of diabetes (OR: 1.072, P=3.77E-7) and poorly controlled HbA1c (OR: 3.522, P=2.00E-5) were associated with greater retinopathy severity. The association between vitamin D deficiency and retinopathy severity only found in diabetic patients with well controlled glycaemia.

CONCLUSIONS

The findings of this study indicate that vitamin D deficiency associated with severe diabetic retinopathy in patients with well controlled diabetes. The findings provide possible relationship for the previous conflict results, and highlight the need for controlling modifiable risk factors to reduce the development of sever diabetic retinopathy.

Novel biomarkers for prediabetes, diabetes, and associated complications

The number of individuals with prediabetes is expected to grow substantially and estimated to globally affect 482 million people by 2040. Therefore, effective methods for diagnosing prediabetes will be required to reduce the risk of progressing to diabetes and its complications. The current biomarkers, glycated hemoglobin (HbA1c), fructosamine, and glycated albumin have limitations including moderate sensitivity and specificity and are inaccurate in certain clinical conditions. Therefore, identification of additional biomarkers is being explored recognizing that any single biomarker will also likely have inherent limitations. Therefore, combining several biomarkers may more precisely identify those at high risk for developing prediabetes and subsequent progression to diabetes. This review describes recently identified biomarkers and their potential utility for addressing the burgeoning epidemic of dysglycemic disorders.

PERFORMANCE OF A1C VERSUS OGTT FOR THE DIAGNOSIS OF PREDIABETES IN A COMMUNITY-BASED SCREENING

OBJECTIVE

Reliable identification of individuals at risk for developing diabetes is critical to instituting preventative strategies. Studies suggest that the accuracy of using hemoglobin A1c as a sole diagnostic criterion for diabetes may be variable across different ethnic groups. We postulate that there will be lack of concordance between A1c and the oral glucose tolerance test (OGTT) for diagnosing prediabetes across Hispanic and non-Hispanic white (NHW) populations.

METHODS

A total of 218 asymptomatic adults at risk for type 2 diabetes (T2D) were assessed with A1c and OGTT for the diagnosis of prediabetes. Glucose homeostasis status was assigned as no diabetes (A1c <5.7% [39 mmol/mol]), prediabetes (A1c 5.7 to 6.4% [46 mmol/mol]), and T2D (A1c >6.4% [46 mmol/mol]). Inclusion criteria were age >18 years and at least one of the following: a family history of diabetes, a history of gestational diabetes, Hispanic ethnicity, non-Caucasian race, or obesity. Subjects received a fasting 75-g OGTT and A1c on the same day. Bowker's test of symmetry was employed to determine agreement between the tests.

RESULTS

Data from 99 Hispanic patients and 79 NHW patients were analyzed. There was no concordance between A1c and OGTT for Hispanic (P = .002) or NHW individuals (P = .003) with prediabetes.

CONCLUSION

A1c is discordant with OGTT among Hispanic and NHW subjects for the diagnosis of prediabetes. Sole use of A1c to designate glycemic status will result in a greater prevalence of prediabetes among Hispanic and NHW New Mexicans.

ABBREVIATIONS

A1c = hemoglobin A1c BMI = body mass index CDC = Centers for Disease Control CI = confidence interval FPG = fasting plasma glucose NHW = non-Hispanic white OGTT = oral glucose tolerance test T2D = type 2 diabetes WHO = World Health Organization.

Glucose: archetypal biomarker in diabetes diagnosis, clinical management and research

The clinical utility of diabetes biomarkers can be considered in terms of diagnosis, management and prediction of long-term vascular complications. Glucose satisfies all of these requirements. Thresholds of hyperglycemia diagnostic of diabetes reflect inflections that confer a risk of developing long-term microvascular complications. Degrees of hyperglycemia (impaired fasting glucose, impaired glucose tolerance) that lie below the diagnostic threshold for diabetes identify individuals at risk of progression to diabetes and/or development of atherothrombotic cardiovascular disease. Self-measured glucose levels usefully complement hemoglobin A1c levels to guide daily management decisions. Continuous glucose monitoring provides detailed real-time data that is of value in clinical decision making, assessing response to new diabetes drugs and the development of closed-loop artificial pancreas technology.

Relationship Between HbA1c and Complex Regional Pain Syndrome in Stroke Patients With Type 2 Diabetes Mellitus

Objective

To investigate the relationship between glycosylated hemoglobin A (HbA1c) and complex regional pain syndrome (CRPS) in stroke patients with type 2 diabetes mellitus (T2DM).

Methods

A retrospective chart review was performed of stroke patients from January 2012 to December 2013. We reviewed 331 patients and included 200 in the analysis. We divided them into CRPS and non-CRPS groups and compared them by age, gender, stroke lesion, cause of stroke, duration of T2DM, HbA1c (%), National Institutes of Health Stroke Scale score, affected shoulder flexor muscle strength, Fugl-Meyer Assessment score, motricity index, Functional Independence Measure, Korean version of Modified Barthel Index, blood glucose level on admission day, duration from stroke onset to HbA1c check, and duration from stroke onset to three-phase bone scan for CRPS diagnosis. Thereafter, we classified the patients into five groups by HbA1c level (group 1, 5.0%–5.9%; group 2, 6.0%–6.9%; group 3, 7.0%–7.9%; group 4, 8.0%–8.9%; and group 5, 9.0%–9.9%) and we investigated the difference in CRPS prevalence between the two groups.

Results

Of the 200 patients, 108 were in the CRPS group and 92 were in the non-CRPS group. There were significant differences in HbA1c (p<0.05) between the two groups but no significant differences in any other factors. Across the five HbA1c groups, there were significant differences in CRPS prevalence (p<0.01); specifically, it increased as HbA1c increased.

Conclusion

This study suggests that higher HbA1c relates to higher CRPS prevalence and thus that uncontrolled blood glucose can affect CRPS occurrence in stroke patients with diabetes.

A Self-assessment Tool for Screening Young Adults at Risk of Type 2 Diabetes Using Strong Heart Family Study Data

PURPOSE

The purpose of this study is to characterize risk factors associated with type 2 diabetes in young adults aged 18 to 29 years to develop a noninvasive risk assessment tool for use with younger American populations.

METHODS

The self-assessment tool was developed with the Strong Heart Family Study data. A total of 590 young American Indian adults (242 men) who had normoglycemia and were not receiving diabetes treatment were included. Risk factors recommended by the American Diabetes Association were used to assess diabetes risk in these young adults. A logistic regression model was developed to calculate the predicted probability. The area under the receiver operating characteristic curve was used to evaluate the model.

RESULTS

The final model showed that parental history of diabetes, obesity level, alcohol consumption, and high fasting glucose, even within normal range, were significantly associated with onset of prediabetes/diabetes in 5 years. The area under the receiver operating characteristic curve value was 0.68 with original and validated data, indicating that the risk assessment tool had reasonably good discrimination ability.

CONCLUSIONS

This new noninvasive screening tool, based on data from American Indian young adults, has potential to screen young adults' early-onset diabetes risk. Future studies are warranted to test this risk assessment tool in other racial/ethnic young adults.

Optimal Glycemic and Hemoglobin A1c Thresholds for Diagnosing Diabetes Based on Prevalence of Retinopathy in an Iranian Population

Background

The use of glycemic thresholds for diabetes diagnosis is controversial. However, no information is available regarding glycemic and glycated hemoglobin (HbA1c) thresholds for detecting diabetic retinopathy (DR) in the Iranian population.

Objectives

The main purpose of the current investigation was to examine the association of fasting plasma glucose (FPG) and HbA1c levels with diabetic retinopathy (DR), and to determine the relevant cut-off levels in an Iranian population.

Patients and Methods

This cross-sectional, population-based study was performed during 2012-2013 in Urmia, the capital of West Azerbaijan province, Iran. The subjects were 3,010 Iranians aged 40-81 years. The FPG levels were determined using the glucose oxidase method whereas, the HbA1c values were measured using a standardized assay by high performance liquid chromatography. DR was evaluated by an examination of the fundus photograph of each eye. The photographs were graded according to the international clinical diabetic retinopathy disease severity scale by photograph graders who were masked to the clinical information.

Results

Of the subjects, 59 had DR. The prevalence of DR increased steeply between the ninth and the tenth deciles for both variables. The ROC curve analysis showed overall glycemic thresholds for DR of 6.5 mmol/L (117 mg/dL) for FPG and 6.2% (44 mmol/mol) for HbA1c. The sensitivities and specificities were 78.0% and 87.1% for FPG and 89.8% and 89.5% for HbA1c, respectively. The areas under the ROC curves indicated that HbA1c was a stronger discriminator of retinopathy: the area under curve was 0.880 for FPG and 0.946 for HbA1c P < 0.001). However, the thresholds for detecting DR for the two measures showed no significant differences after excluding individuals receiving anti-hyperglycemic medication.

Conclusions

These findings suggest that the HbA1c and FPG thresholds for detecting diabetes in the Iranian population are lower than the current diagnostic criteria.

[Diabetes mellitus and cardiovascular risk: Working group recommendations of Diabetes and Cardiovascular Disease of the Spanish Society of Diabetes (SED, 2015)]

The present paper updates the Clinical Practice Recommendations for the management of cardiovascular risk factors (CVRF) in diabetes mellitus. This is a medical consensus agreed by an independent panel of experts from the Spanish Society of Diabetes (SED). Several consensuses have been proposed by scientific and medical Societies to achieve clinical goals. However, the risk score for general population may lack sensitivity for individual assessment or for particular groups at risk, such as diabetics. Traditional risk factors together with non-traditional factors are reviewed throughout this paper. Intervention strategies for managing CVRF in the diabetic patient are reviewed in detail: balanced food intake, weight reduction, physical exercise, smoking cessation, reduction in HbA1c, therapy for high blood pressure, obesity, lipid disorders, and platelet anti-aggregation. It is hoped that these guidelines can help clinicians in the decisions of their clinical activity. This regular update by the SED Cardiovascular Disease Group of the most relevant concepts, and of greater practical and realistic clinical interest, is presented in order to reduce CVR of diabetics.

The Accuracy of Diagnostic Methods for Diabetic Retinopathy: A Systematic Review and Meta-Analysis

OBJECTIVE

The objective of this study was to evaluate the accuracy of the recommended glycemic measures for diagnosing diabetic retinopathy.

METHODS

We systematically searched MEDLINE, EMBASE, the Cochrane Library, and the Web of Science databases from inception to July 2015 for observational studies comparing the diagnostic accuracy of glycated hemoglobin (HbA1c), fasting plasma glucose (FPG), and 2-hour plasma glucose (2h-PG). Random effects models for the diagnostic odds ratio (dOR) value computed by Moses' constant for a linear model and 95% CIs were used to calculate the accuracy of the test. Hierarchical summary receiver operating characteristic curves (HSROC) were used to summarize the overall test performance.

RESULTS

Eleven published studies were included in the meta-analysis. The pooled dOR values for the diagnosis of retinopathy were 16.32 (95% CI 13.86-19.22) for HbA1c and 4.87 (95% CI 4.39-5.40) for FPG. The area under the HSROC was 0.837 (95% CI 0.781-0.892) for HbA1c and 0.735 (95% CI 0.657-0.813) for FPG. The 95% confidence region for the point that summarizes the overall test performance of the included studies occurs where the cut-offs ranged from 6.1% (43.2 mmol/mol) to 7.8% (61.7 mmol/mol) for HbA1c and from 7.8 to 9.3 mmol/L for FPG. In the four studies that provided information regarding 2h-PG, the pooled accuracy estimates for HbA1c were similar to those of 2h-PG; the overall performance for HbA1c was superior to that for FPG.

CONCLUSIONS

The three recommended tests for the diagnosis of type 2 diabetes in nonpregnant adults showed sufficient accuracy for their use in clinical settings, although the overall accuracy for the diagnosis of retinopathy was similar for HbA1c and 2h-PG, which were both more accurate than for FPG. Due to the variability and inconveniences of the glucose level-based methods, HbA1c appears to be the most appropriate method for the diagnosis diabetic retinopathy.

Analysis and Quantitation of Glycated Hemoglobin by Matrix Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry

Measurement of glycated hemoglobin is widely used for the diagnosis and monitoring of diabetes mellitus. Matrix assisted laser desorption/ionization (MALDI) time of flight (TOF) mass spectrometry (MS) analysis of patient samples is used to demonstrate a method for quantitation of total glycation on the β-subunit of hemoglobin. The approach is accurate and calibrated with commercially available reference materials. Measurements were linear (R(2) > 0.99) across the clinically relevant range of 4% to 20% glycation with coefficients of variation of ≤ 2.5%. Additional and independent measurements of glycation of the α-subunit of hemoglobin are used to validate β-subunit glycation measurements and distinguish hemoglobin variants. Results obtained by MALDI-TOF MS were compared with those obtained in a clinical laboratory using validated HPLC methodology. MALDI-TOF MS sample preparation was minimal and analysis times were rapid making the method an attractive alternative to methodologies currently in practice.

Rational diagnoses of diabetes: the comparison of 1,5-anhydroglucitol with other glycemic markers

Diabetes mellitus (DM) is a frequently encountered disease with important morbidity and mortality. The aim of this study is to document the importance of 1,5-anhydroglucitol (1,5-AG) for the diagnosis of prediabetes and DM, as well as to compare the 1,5-AG with other glycemic markers in order to understand which one is the better diagnostic tool. Between April 2012 and December 2012, 128 participants enrolled in the study. Participants were split into five groups that are IFG, IGT, IFG+IGT, diabetic and control groups by their OGTT results. The diagnostic value of markers was compared by ROC (receiver operating characteristic) method. The mean serum 1,5-AG levels in the diabetic group (33.38 nmol/ml) were lower than, IFG (59.83 nmol/ml), IGT (54.44 nmol/ml), IFG+IGT (51.98 nmol/ml) and control groups (73.24 nmol/ml). When analyzed in the total study population serum 1,5-AG levels did not differ by gender significantly. When analyzed in the total study population, 1,5-AG correlates inversely with age significantly (p = 0.036). In subgroup analysis, in the control group, serum 1,5-AG level was also inversely correlated with age (p = 0.087). The best marker for the diagnosis of prediabetes and DM was fasting plasma glucose (FPG). 1,5-AG was not found to be effective for the diagnosis of DM. This study, contributes to our knowledge of the efficiency and cut-off values of 1,5-AG for the diagnosis of prediabetes and DM. In future, there is a need for larger studies with more standardized and commonly used measurement methods for 1,5-AG, in order to evaluate the efficiency of 1,5-AG for the diagnosis of prediabetes and DM.

The Uptake of Screening for Type 2 Diabetes and Prediabetes by Means of Glycated Hemoglobin versus the Oral Glucose Tolerance Test among 18 to 60-Year-Old People of South Asian Origin: A Comparative Study

Background

Direct comparisons of the effect of a glycated haemoglobin measurement or an oral glucose tolerance test on the uptake and yield of screening in people of South Asian origin have not been made. We evaluated this in 18 to 60-year-old South Asian Surinamese.

Materials and Methods

We invited 3173 South Asian Surinamese for an oral glucose tolerance test between June 18^th 2009- December 31^st 2009 and 2012 for a glycated hemoglobin measurement between April 19^th 2010-November 11^th, 2010. Participants were selected from 48 general practices in The Hague, The Netherlands. We used mixed models regression to analyse differences in response and participation between the groups. We described differences in characteristics of participants and calculated the yield as the percentage of all cases identified, if all invitees had been offered screening with the specified method.

Results

The response and participation in the glycated hemoglobin group was higher than in the group offered an oral glucose tolerance test (participation 23.9 vs. 19.3; OR: 1.30, 95%-confidence interval1.01–1.69). After adjustment for age and sex, characteristics of participants were similar for both groups. Overall, glycated hemoglobin identified a similar percentage of type 2 diabetes cases but a higher percentage of prediabetes cases, in the population than the oral glucose tolerance test.

Conclusion

We found that glycated hemoglobin and the oral glucose tolerance test may be equally efficient for identification of type 2 diabetes in populations of South Asian origin. However, for programs aimed at identifying people at high risk of type 2 diabetes (i.e. with prediabetes), the oral glucose tolerance test may be a less efficient choice than glycated hemoglobin.

The cutoffs and performance of glycated hemoglobin for diagnosing diabetes and prediabetes in a young and middle-aged population and in an elderly population

The aims were to compare the appropriate cutoffs of glycated hemoglobin (HbA1c) in a population of varying ages and to evaluate the performance of HbA1c for diagnosing diabetes and prediabetes. A total of 1064 participants in the young and middle-aged group and 1671 in the elderly group were included and underwent HbA1c testing and an oral glucose tolerance test (OGTT). Sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) were calculated to evaluate the optimal HbA1c cutoffs. Kappa coefficients were used to test for agreement between HbA1c categorization and OGTT-based diagnoses. The optimal HbA1c cutoffs for diagnosing diabetes were 5.7% (39 mmol/mol) in the young and middle-aged group with a sensitivity of 66.7%, specificity of 86.7%, and AUC of 0.821 (95% CI: 0.686, 0.955) and 5.9% (41 mmol/mol) in the elderly group with a sensitivity of 80.4%, specificity of 73.3%, and AUC of 0.831 (0.801, 0.861). The optimal cutoffs for diagnosing prediabetes were 5.6% (38 mmol/mol) and 5.7% (39 mmol/mol) in the young and middle-aged group and in the elderly group, respectively. Agreement between the OGTT-based diagnosis of diabetes or prediabetes and the optimal HbA1c cutoff was low (all kappa coefficients <0.4). The combination of HbA1c and fasting plasma glucose increased diagnostic sensitivities or specificities. In conclusion, age-specific HbA1c cutoffs for diagnosing diabetes or prediabetes were appropriate. Furthermore, the performance of HbA1c for diagnosing diabetes and prediabetes was poor. HbA1c should be used in combination with traditional glucose criteria when detecting and diagnosing diabetes or prediabetes.

Diabetes mellitus: The epidemic of the century

The epidemic nature of diabetes mellitus in different regions is reviewed. The Middle East and North Africa region has the highest prevalence of diabetes in adults (10.9%) whereas, the Western Pacific region has the highest number of adults diagnosed with diabetes and has countries with the highest prevalence of diabetes (37.5%). Different classes of diabetes mellitus, type 1, type 2, gestational diabetes and other types of diabetes mellitus are compared in terms of diagnostic criteria, etiology and genetics. The molecular genetics of diabetes received extensive attention in recent years by many prominent investigators and research groups in the biomedical field. A large array of mutations and single nucleotide polymorphisms in genes that play a role in the various steps and pathways involved in glucose metabolism and the development, control and function of pancreatic cells at various levels are reviewed. The major advances in the molecular understanding of diabetes in relation to the different types of diabetes in comparison to the previous understanding in this field are briefly reviewed here. Despite the accumulation of extensive data at the molecular and cellular levels, the mechanism of diabetes development and complications are still not fully understood. Definitely, more extensive research is needed in this field that will eventually reflect on the ultimate objective to improve diagnoses, therapy and minimize the chance of chronic complications development.

Prevalence and Cardiovascular Associations of Diabetic Retinopathy and Maculopathy: Results from the Gutenberg Health Study

Objective

Diabetic retinopathy (DR) is the leading cause of blindness in people of working age. The purpose of this paper is to report the prevalence and cardiovascular associations of diabetic retinopathy and maculopathy (DMac) in Germany.

Research Design and Methods

The Gutenberg Health Study (GHS) is a population-based study with 15,010 participants aged between 35 at 74 years from the city of Mainz and the district of Mainz-Bingen. We determined the weighted prevalence of DR and DMac by assessing fundus photographs of persons with diabetes from the GHS data base. Diabetes was defined as HbA1c ≥ 6.5%, known diagnosis diabetes mellitus or known diabetes medication. Furthermore, we analysed the association between DR and cardiovascular risk factors and diseases.

Results

Overall, 7.5% (1,124/15,010) of the GHS cohort had diabetes. Of these, 27.7% were unaware of their disease and thus were newly diagnosed by their participation in the GHS. The prevalence of DR and DMac was 21.7% and 2.3%, respectively among patients with diabetes. Vision-threatening disease was present in 5% of the diabetic cohort. In the multivariable analysis DR (all types) was associated with age (Odds Ratio [95% confidence interval]: 0.97 [0.955–0.992]; p = 0.006) arterial hypertension (1.90 [1.190–3.044]; p = 0.0072) and vision-threatening DR with obesity (3.29 [1.504–7.206]; p = 0.0029). DR (all stages) and vision-threatening DR were associated with duration of diabetes (1.09 [1.068–1.114]; p<0.0001 and 1.18 [1.137–1.222]; p<0.0001, respectively).

Conclusions

Our calculations suggest that more than a quarter-million persons have vision-threatening diabetic retinal disease in Germany. Prevalence of DR was lower in the GHS compared to East-Asian studies. Associations were found with age, arterial hypertension, obesity, and duration of diabetes mellitus.

Screening for dysglycaemia in patients with coronary artery disease as reflected by fasting glucose, oral glucose tolerance test, and HbA1c: a report from EUROASPIRE IV--a survey from the European Society of Cardiology

AIMS

Three methods are used to identify dysglycaemia: fasting plasma glucose (FPG), 2-h post-load plasma glucose (2hPG) from the oral glucose tolerance test (OGTT), and glycated haemoglobin A1c (HbA1c). The aim was to describe the yield and concordance of FPG, HbA1c, and 2hPG alone, or in combination, to identify dysglycaemia in patients with coronary artery disease.

METHODS AND RESULTS

In EUROASPIRE IV, a cross-sectional survey of patients aged 18-80 years with coronary artery disease in 24 European countries, 4004 patients with no reported history of diabetes had FPG, 2hPG, and HbA1c measured. All participants were divided into different glycaemic categories according to the ADA and WHO criteria for dysglycaemia. Using all screening tests together, 1158 (29%) had undetected diabetes. Out of them, the proportion identified by FPG was 75%, by 2hPG 40%, by HbA1c 17%, by FPG + HbA1c 81%, and by OGTT (=FPG + 2hPG) 96%. Only 7% were detected by all three methods FPG, 2hPG, and HbA1c. The ADA criteria (FPG + HbA1c) identified 90% of the population as having dysglycaemia compared with 73% with the WHO criteria (OGTT = FPG + 2hPG). Screening according to the ADA criteria for FPG + HbA1c identified 2643 (66%) as having a 'high risk for diabetes', while the WHO criteria for FPG + 2hPG identified 1829 patients (46%).

CONCLUSION

In patients with established coronary artery disease, the OGTT identifies the largest number of patients with previously undiagnosed diabetes and should be the preferred test when assessing the glycaemic state of such patients.

Treatment-dependent and treatment-independent risk factors associated with the risk of diabetes-related events: a retrospective analysis based on 229,042 patients with type 2 diabetes mellitus

BACKGROUND

The aim of this study was to analyse which factors predict the real-world macro-/microvascular event, hospitalisation and death risk in patients with type 2 diabetes mellitus. Furthermore, we aimed to investigate whether there exists both an under- and over-treatment risk of these patients.

METHODS

We used a German claims/clinical data set covering the years 2010-12. Diabetes-related events were defined as (1) macro-, (2) microvascular events leading to inpatient hospitalisation, (3) other hospitalisations with type 2 diabetes mellitus as main diagnosis, (4) all-cause death and (5) a composite outcome including all event categories 1-4. Factors associated with event risk were analysed by a Kaplan-Meier curve analysis and by multivariable Cox regression models.

RESULTS

229,042 patients with type 2 diabetes mellitus (mean age 70.2 years; mean CCI 6.03) were included. Among factors that increased the event risk were patients' age, male gender, the adapted Charlson Comorbidity Index, the adapted Diabetes Complication Severity Index, previous events, and number of prescribed chronic medications. For systolic blood pressure/HbA1C, a double-J/U-curve pattern was detected: HbA1C of 6-6.5% (42-48 mmol/mol) and systolic blood pressure of 130-140 mmHg (17.3-18.7kPa) were associated with the lowest event risk, values below/above that range were associated with higher risk. However, this pattern was mainly driven by the death risk and was much less clearly observed for the macrovascular/microvascular/hospitalization risk and for young/less comorbid patients.

CONCLUSIONS

Both blood pressure and HbA1C seem to be very important treatment targets, especially in comorbid old patients. It is of particular clinical importance that both over- and under-treatment pose a threat to patients with type 2 diabetes mellitus.

Selection of aptamers specific for glycated hemoglobin and total hemoglobin using on-chip SELEX

Blood glycated hemoglobin (HbA1c) levels reflecting average glucose concentrations over the past three months are fundamental for the diagnosis, monitoring, and risk assessment of diabetes. It has been hypothesized that aptamers, which are single-stranded DNAs or RNAs that demonstrate high affinity to a large variety of molecules ranging from small drugs, metabolites, or proteins, could be used for the measurement of HbA1c. Aptamers are selected through an in vitro process called systematic evolution of ligands by exponential enrichment (SELEX), and they can be chemically synthesized with high reproducibility at relatively low costs. This study therefore aimed to select HbA1c- and hemoglobin (Hb)-specific single-stranded DNA aptamers using an on-chip SELEX protocol. A microfluidic SELEX chip was developed to continuously and automatically carry out multiple rounds of SELEX to screen specific aptamers for HbA1c and Hb. HbA1c and Hb were first coated onto magnetic beads. Following several rounds of selection and enrichment with a randomized 40-mer DNA library, specific oligonucleotides were selected. The binding specificity and affinity were assessed by competitive and binding assays. Using the developed microfluidic system, the incubation and partitioning times were greatly decreased, and the entire process was shortened dramatically. Both HbA1c- and Hb-specific aptamers selected by the microfluidic system showed high specificity and affinity (dissociation constant, Kd = 7.6 ± 3.0 nM and 7.3 ± 2.2 nM for HbA1c and Hb, respectively). With further refinements in the assay, these aptamers may replace the conventional antibodies for in vitro diagnostics applications in the near future.

Inverse Association between Vitamin D Status and Diabetes in a Clinic Based Sample of Hispanic Adults in Puerto Rico

BACKGROUND

Vitamin D deficiency is a public health problem around the world. Diabetes has been associated with vitamin D deficiency. We aimed to examine the association between the vitamin D status and diabetes in a clinic based sample of Hispanic adults in Puerto Rico.

METHODS

Demographics and laboratory test results for serum 25(OH)D, Fasting Blood Glucose (FBG), and Haemoglobin A1C (HbAlc) were extracted from medical records. Vitamin D status was classified as deficient (<12 ng/ml); inadequate (12-20 ng/ml); insufficient (21-29 ng/ml) and optimal (≥30 ng/ml) using serum 25(OH)D levels.

RESULTS

A total of 716 records were included in the analyses. Most were females (63.3%), with mean age of 54.1±14.9 y, mean BMI 30.1±6.3 kg/m2 and mean serum 25(OH)D levels of 24.3±8.6 ng/ml. Most were classified as diabetics (41.1%). Those with diabetes had lower 25(OH)D levels compared to pre-diabetic and normal glucose status (p<0.05). Serum 25(OH) D levels were inversely correlated to FBG and HbA1c in the total sample and in men (p<0.05). After adjusting for age, gender, BMI and seasonality, there was a greater risk of diabetes, but not prediabetes, in those with serum 25(OH)D levels <30 ng/ml. This risk increased from 1.8 times in those with vitamin D insufficiency to 4.2 times in those with vitamin D deficiency (<12 ng/ml).

CONCLUSION

Diabetes risk significantly increased as serum 25(OH)D levels decreased in this group of Hispanic adults, underscoring the importance of routinely screening high risk individuals for vitamin D deficiency and offer supplementation to normalize serum levels.

Trends in diabetes incidence among 7 million insured adults, 2006-2011: the SUPREME-DM project

An observational cohort analysis was conducted within the Surveillance, Prevention, and Management of Diabetes Mellitus (SUPREME-DM) DataLink, a consortium of 11 integrated health-care delivery systems with electronic health records in 10 US states. Among nearly 7 million adults aged 20 years or older, we estimated annual diabetes incidence per 1,000 persons overall and by age, sex, race/ethnicity, and body mass index. We identified 289,050 incident cases of diabetes. Age- and sex-adjusted population incidence was stable between 2006 and 2010, ranging from 10.3 per 1,000 adults (95% confidence interval (CI): 9.8, 10.7) to 11.3 per 1,000 adults (95% CI: 11.0, 11.7). Adjusted incidence was significantly higher in 2011 (11.5, 95% CI: 10.9, 12.0) than in the 2 years with the lowest incidence. A similar pattern was observed in most prespecified subgroups, but only the differences for persons who were not white were significant. In 2006, 56% of incident cases had a glycated hemoglobin (hemoglobin A1c) test as one of the pair of events identifying diabetes. By 2011, that number was 74%. In conclusion, overall diabetes incidence in this population did not significantly increase between 2006 and 2010, but increases in hemoglobin A1c testing may have contributed to rising diabetes incidence among nonwhites in 2011.

Skin pH is lower in type 1 diabetes subjects and is related to glycemic control of the disease

BACKGROUND

Diabetes is a systemic disease affecting many organs, including skin. Skin may reflect the condition of internal organs. The aim of our study was to measure skin pH in type 1 diabetes mellitus (T1DM) patients and in healthy controls and to evaluate the association between metabolic control of diabetes and skin acidity in T1DM patients.

MATERIALS AND METHODS

The study was conducted on 105 patients with T1DM and 53 age- and sex-matched healthy people. Skin surface pH was measured in three different areas of the body (cheek, forearm, and foot) in diabetes patients and healthy controls. The results were compared for patients' and controls' clinical characteristics and for patients' metabolic control and also evaluated according to the presence of complications of diabetes.

RESULTS

Patients with T1DM had lower skin pH compared with the control group in three measured areas: within the cheek (5.49 ± 0.42 vs. 5.69 ± 0.31; P = 0.001), forearm (5.41 ± 0.46 vs. 5.73 ± 0.69; P = 0.004), and foot (5.20 ± 0.53 vs. 5.41 ± 0.41; P = 0.008). In the multiple linear regression skin pH was negatively correlated with fasting plasma glucose on the cheek (β = -0.34, P = 0.0004), forearm (β = -0.30, P = 0.0009), and foot (β = -0.18, P = 0.04). Diabetes patients with glycated hemoglobin (HbA1c) ≥ 8% had significantly lower skin pH than patients with better glycemic control (HbA1c < 8%). However, we observed a statistically significant difference only on the foot (5.09 ± 0.50 vs. 5.34 ± 0.55; P = 0.019).

CONCLUSIONS

Skin surface pH is lower in individuals with diabetes, and it is negatively related to actual and chronic hyperglycemia.

A novel model enhances HbA1c-based diabetes screening using simple anthropometric, anamnestic, and demographic information

BACKGROUND

The sensitivity of HbA1c is not optimal for the screening of patients with latent diabetes. We hypothesize that simple healthcare information could improve accuracy.

METHODS

We retrospectively analyzed data, including HbA1c, from multiple years from the National Health and Nutrition Examination Survey (NHANES) database (2005-2010). The data were used to create a logistic regression classification model for screening purposes.

RESULTS

The study evaluated data for 5381 participants, including 404 with undiagnosed diabetes. The HbA1c screening data were supplemented with information about age, waist circumference, and physical activity in the HbA1c+ model. Alone, HbA1c alone had a receiver operating characteristics (ROC) curve for the area under the curve (AUC) of 0.808 (95% confidence interval [CI] 0.792-0.834). The HbA1c+ model had an ROC AUC of 0.851 (95% CI 0.843-0.872). There was a significant difference in the AUC between our model and using HbA1c without supplementary information (P < 0.05).

CONCLUSIONS

We have developed a novel screening model that could help improve screening for type 2 diabetes with HbA1c. It seems beneficial to systematically add additional patient healthcare information in the process of screening with HbA1c.