Current aspects in hemoglobin A1c detection: A review

Emerging biosensor probes for glycated hemoglobin (HbA1c) detection

Glycated hemoglobin (HbA1c), originating from the non-enzymatic glycosylation of βVal1 residues in hemoglobin (Hb), is an essential biomarker indicating average blood glucose levels over a period of 2 to 3 months without external environmental disturbances, thereby serving as the gold standard in the management of diabetes instead of blood glucose testing. The emergence of HbA1c biosensors presents affordable, readily available options for glycemic monitoring, offering significant benefits to small-scale laboratories and clinics. Utilizing nanomaterials coupled with high-specificity probes as integral components for recognition, labeling, and signal transduction, these sensors demonstrate exceptional sensitivity and selectivity in HbA1c detection. This review mainly focuses on the emerging probes and strategies integral to HbA1c sensor development. We discussed the advantages and limitations of various probes in sensor construction as well as recent advances in diverse sensing strategies for HbA1c measurement and their potential clinical applications, highlighting the critical gaps in current technologies and future needs in this evolving field.

The effect of nurse-led telephone-based interventions on glycosylated hemoglobin levels in people with type 2 diabetes: A meta-analysis

BACKGROUND

Telenursing interventions can contribute to achieving optimal glycemic control.

AIM

This meta-analysis aimed to determine the effect of nurse-led telephone-based interventions on glycosylated hemoglobin (HbA1c) levels in people with type 2 diabetes.

METHODS

We searched electronic databases for studies published in English up to January 2023. This study was conducted in accordance with the PRISMA 2020 checklist. The intervention effects were pooled using a random-effects model. Two authors independently assessed the risk of bias using the Cochrane Collaboration tool.

RESULTS

Eight studies involving 1179 people with type 2 diabetes were included in this study. Interventions were performed for 15-30 min and 5-16 calls. There was no evidence of a significant publication bias. The evaluation of meta-analysis data showed that nurse-led telephone-based interventions significantly reduced HbA1c levels in people with type 2 diabetes (mean difference = -0.53, 95% Confidence Interval [-0.89, -0.17], p = .003).

LINKING EVIDENCE TO ACTION

Nurse-led telephone-based interventions focused on reducing glycosylated hemoglobin levels in people with type 2 diabetes can be used as an effective intervention to achieve glycemic control. We recommend holding an average of 15-25 min interviews once or twice a week.

Optimal Dose and Type of Physical Activity to Improve Glycemic Control in People Diagnosed With Type 2 Diabetes: A Systematic Review and Meta-analysis

BACKGROUND

The optimal dose or type of physical activity to control glycosylated hemoglobin (HbA1c) in people with diabetes remains unknown. Current guidelines do not include consideration of baseline HbA1c for activity prescription.

PURPOSE

To examine the dose-response relationship between physical activity and HbA1c (%) in individuals with type 2 diabetes.

DATA SOURCES

A systematic search was performed in Embase, MEDLINE, Scopus, CINAHL, SPORTDiscus, and Web of Science.

STUDY SELECTION

We included trials that involved participants diagnosed with type 2 diabetes that included any type of physical activity as intervention.

DATA EXTRACTION

Pre- and postintervention HbA1c data, population and interventions characteristics, and descriptive statistics were collected to calculate change scores for each study arm.

DATA SYNTHESIS

We used Bayesian random-effects meta-analyses to summarize high-quality evidence from 126 studies (6,718 participants). The optimal physical activity dose was 1,100 MET min/week, resulting in HbA1c reductions, ranging from -1.02% to -0.66% in severe uncontrolled diabetes, from -0.64% to -0.49% in uncontrolled diabetes, from -0.47% to -0.40% in controlled diabetes, and from -0.38% to -0.24% in prediabetes.

LIMITATIONS

The time required to achieve these HbA1c reductions could not be estimated due to the heterogeneity between interventions' duration and protocols and the interpersonal variability of this outcome.

CONCLUSIONS

The result of this meta-analysis provide key information about the optimal weekly dose of physical activity for people with diabetes with consideration of baseline HbA1c level, and the effectiveness of different types of active interventions. These results enable clinicians to prescribe tailored physical activity programs for this population.

Diagnosis and screening of abnormal hemoglobins

Hemoglobin (Hb) abnormalities, such as thalassemia and structural Hb variants, are among the most prevalent inherited diseases and are associated with significant mortality and morbidity worldwide. However, there were not comprehensive reviews focusing on different clinical analytical techniques, research methods and artificial intelligence (AI) used in clinical screening and research on hemoglobinopathies. Hence the review offers a comprehensive summary of recent advancements and breakthroughs in the detection of aberrant Hbs, research methods and AI uses as well as the present restrictions anddifficulties in hemoglobinopathies. Recent advances in cation exchange high performance liquid chromatography (HPLC), capillary zone electrophoresis (CZE), isoelectric focusing (IEF), flow cytometry, mass spectrometry (MS) and polymerase chain reaction (PCR) etc have allowed for the definitive detection by using advanced AIand portable point of care tests (POCT) integrating with smartphone microscopic classification, machine learning (ML) model, complete blood counts (CBC), imaging-based method, speedy immunoassay, and electrochemical-, microfluidic- and sensing-related platforms. In addition, to confirm and validate unidentified and novel Hbs, highly specialized genetic based techniques like PCR, reverse transcribed (RT)-PCR, DNA microarray, sequencing of genomic DNA, and sequencing of RT-PCR amplified globin cDNA of the gene of interest have been used. Hence, adequate utilization and improvement of available diagnostic and screening technologies are important for the control and management of hemoglobinopathies.

Lipoxygenase-12 Levels and Biochemical Parameters in Iraqi Patients With Type 2 Diabetes With and Without Benign Prostatic Hyperplasia

Background Diabetes mellitus (DM) is a chronic metabolic disorder characterized by hyperglycemia caused by a defect in the secretion or action or both of insulin. It has a complex pathogenesis. Benign prostatic hyperplasia (BPH) refers to an increase in the size of the prostate; it is one of the most common health problems in men that manifests with age. Lipoxygenase-12 (Lipox-12) is one of the enzymes in the Lipox 12/15 family, which plays a major role in catalyzing a variety of polyunsaturated fatty acids (PUFAs) that are capable of producing different metabolites. Lipox-12 has a significant effect on arachidonic acid metabolism, with PUFA, a pro- and anti-inflammatory mediator, as one of the enzyme isoforms. It also plays a major role in modulating inflammation at multiple checkpoints as diabetes progresses. The present study aims to measure Lipox-12 levels in patients with DM type 2 (DM2) and patients with DM2 + BPH. Methodology This study was conducted in Musayyib General Hospital, south of Baghdad, where a clinical examination was performed on 50 samples from controls (healthy subjects), 50 patients with DM2, and 50 patients with DM2 + BPH after taking each patient's history. The examinations performed included fasting blood sugar (FBS), hemoglobin A1c (HbA1c), prostate-specific antigen (PSA), triglycerides (TG), cholesterol (Chol), and Lipox-12. Results The results showed that both the DM2 and DM2 + BPH groups had higher FBS, HbA1c, TG, and Chol levels than healthy subjects; in contrast, Lipox-12 levels were the lowest in the DM2 group (sensitivity = 79% and specificity = 81%) but higher in the DM2 + BPH group (sensitivity = 80%; specificity = 82%) compared to the control group. Conclusions Lipox-12 had a high sensitivity and specificity in the DM2 and DM2 + BPH groups compared to the control group, and in both cases, it was used to monitor and diagnose DM2 and BPH.

The Reversion of the Epigenetic Signature of Coronary Heart Disease in Response to Smoking Cessation

Coronary heart disease (CHD) is the leading cause of death worldwide. However, current diagnostic tools for CHD, such as coronary computed tomography angiography (CCTA), are poorly suited for monitoring treatment response. Recently, we have introduced an artificial-intelligence-guided integrated genetic-epigenetic test for CHD whose core consists of six assays that determine methylation in pathways known to moderate the pathogenesis of CHD. However, whether methylation at these six loci is sufficiently dynamic to guide CHD treatment response is unknown. To test that hypothesis, we examined the relationship of changes in these six loci to changes in cg05575921, a generally accepted marker of smoking intensity, using DNA from a cohort of 39 subjects undergoing a 90-day smoking cessation intervention and methylation-sensitive digital PCR (MSdPCR). We found that changes in epigenetic smoking intensity were significantly associated with reversion of the CHD-associated methylation signature at five of the six MSdPCR predictor sites: cg03725309, cg12586707, cg04988978, cg17901584, and cg21161138. We conclude that methylation-based approaches could be a scalable method for assessing the clinical effectiveness of CHD interventions, and that further studies to understand the responsiveness of these epigenetic measures to other forms of CHD treatment are in order.

Impact of Poorly Controlled Diabetes and Glycosylated Hemoglobin Values in Geriatric Hip Fracture Mortality Risk Assessment

Introduction The presence of poorly-controlled diabetes in the setting of geriatric hip fractures has been shown to increase all-cause mortality and worsen outcomes. This study aimed to assess whether the addition of a patient's glycated hemoglobin (A1c) value to a validated geriatric inpatient risk tool improves the predictive capacity of the risk tool. Methods A cohort of 2430 patients >55 years old treated for low-energy mechanism hip fractures between October 2014 to November 2021 were reviewed for demographics (including diabetes diagnoses and their respective hemoglobin A1c values at the time of admission), injury details, hospital quality measures, and mortality. As past work demonstrated a hemoglobin A1c value above 8% to be the tipping point for worse outcomes, the baseline Score for Trauma Triage in the Geriatric and Middle-Aged (STTGMA) tool for inpatient mortality in hip fractures (STTGMAHIP_FX_SCORE - Score for Trauma Triage in the Geriatric and Middle-Aged Hip Fracture Score) was modified to include a patient's hemoglobin A1c using an 8% cutoff (STTGMAHIP_8%A1c - Score for Trauma Triage in the Geriatric and Middle-Aged Hip 8% Hemoglobin A1c Cutoff Score). The new model's predictive ability (as measured by the area under the receiver operating curves (AUROCs)) for inpatient mortality was compared to the baseline tool using DeLong's test. Risk quartiles were generated for the new tool, and comparative analyses were conducted on hospital quality measures and outcomes.  Results Five hundred and sixty-five patients (23%) were noted to have diabetes mellitus, and 76 patients had an A1c above 8%. Patients with a hemoglobin A1c above 8% had a higher rate of inpatient complications and mortality through one year. The STTGMAHIP_8%A1c score significantly improved the predictive capacity for inpatient mortality compared to STTGMAHIP_FX_SCORE (0.786 vs. 0.672, p=0.0456). Upon analysis of the risk quartiles, the highest risk cohort was found to have a longer length of stay (p<0.001), with higher rates of inpatient (p<0.001) and 30-day mortality (p<0.001) and need for admission to the intensive care unit (p<0.001) as compared to the minimal risk cohort. Patients in the lowest risk quartile were most likely to be discharged home (p<0.001). Conclusion Patients who present with a hemoglobin A1c above 8% experienced significantly worse outcomes than those below 8%. The inclusion of a patient's hemoglobin A1c as a cutoff score improves the STTGMAHIP_FX_SCORE tool to predict mortality and risk stratify patient outcomes. While diabetes presents another medical challenge to manage, providers may utilize this new variable to better highlight at-risk diabetic patients.

Deep Learning Algorithms for Screening and Diagnosis of Systemic Diseases Based on Ophthalmic Manifestations: A Systematic Review

Deep learning (DL) is the new high-profile technology in medical artificial intelligence (AI) for building screening and diagnosing algorithms for various diseases. The eye provides a window for observing neurovascular pathophysiological changes. Previous studies have proposed that ocular manifestations indicate systemic conditions, revealing a new route in disease screening and management. There have been multiple DL models developed for identifying systemic diseases based on ocular data. However, the methods and results varied immensely across studies. This systematic review aims to summarize the existing studies and provide an overview of the present and future aspects of DL-based algorithms for screening systemic diseases based on ophthalmic examinations. We performed a thorough search in PubMed^®, Embase, and Web of Science for English-language articles published until August 2022. Among the 2873 articles collected, 62 were included for analysis and quality assessment. The selected studies mainly utilized eye appearance, retinal data, and eye movements as model input and covered a wide range of systemic diseases such as cardiovascular diseases, neurodegenerative diseases, and systemic health features. Despite the decent performance reported, most models lack disease specificity and public generalizability for real-world application. This review concludes the pros and cons and discusses the prospect of implementing AI based on ocular data in real-world clinical scenarios.

Trends in Quantification of HbA1c Using Electrochemical and Point-of-Care Analyzers

Glycated hemoglobin (HbA1c), one of the many variants of hemoglobin (Hb), serves as a standard biomarker of diabetes, as it assesses the long-term glycemic status of the individual for the previous 90-120 days. HbA1c levels in blood are stable and do not fluctuate when compared to the random blood glucose levels. The normal level of HbA1c is 4-6.0%, while concentrations > 6.5% denote diabetes. Conventionally, HbA1c is measured using techniques such as chromatography, spectroscopy, immunoassays, capillary electrophoresis, fluorometry, etc., that are time-consuming, expensive, and involve complex procedures and skilled personnel. These limitations have spurred development of sensors incorporating nanostructured materials that can aid in specific and accurate quantification of HbA1c. Various chemical and biological sensing elements with and without nanoparticle interfaces have been explored for HbA1c detection. Attempts are underway to improve the detection speed, increase accuracy, and reduce sample volumes and detection costs through different combinations of nanomaterials, interfaces, capture elements, and measurement techniques. This review elaborates on the recent advances in the realm of electrochemical detection for HbA1c detection. It also discusses the emerging trends and challenges in the fabrication of effective, accurate, and cost-effective point-of-care (PoC) devices for HbA1c and the potential way forward.

Interference of hemoglobin variants in HbA1c quantification

Fasting blood glucose and glycated hemoglobin (HbA_1c) are routine biomarkers to screen and monitor diabetes mellitus. HbA_1c results from glycation at the N-terminus of the β globin chain of tetrameric human hemoglobin. Fasting blood glucose level varies with the nature and amount of food intake, physical exercise, etc., and, accordingly, is a short-term measure of glucose control. In contrast, HbA_1c provides an average measure of glucose control for the long-term (8-12 weeks). Unfortunately, genetic variants of hemoglobin may interfere with HbA_1c quantification using ion exchange chromatography, capillary electrophoresis, immunoassay and boronate affinity chromatography. Mass spectrometry, however, measures total glycation of hemoglobin across both α and β globin chains and correlates well with the ion exchange based method. Additionally, mass spectrometry based quantification is not impacted by the presence of genetic variants of hemoglobin and thus might be a better analytical choice for diabetes mellitus.

Earlier Detection of Alzheimer's Disease Based on a Novel Biomarker cis P-tau by a Label-Free Electrochemical Immunosensor

Early detection of cis phosphorylated tau (cis P-tau) may help as an effective treatment to control the progression of Alzheimer's disease (AD). Recently, we introduced for the first time a monoclonal antibody (mAb) with high affinity against cis P-tau. In this study, the cis P-tau mAb was utilized to develop a label-free immunosensor. The antibody was immobilized onto a gold electrode and the electrochemical responses to the analyte were acquired by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and differential pulse voltammetry (DPV). The immunosensor was capable of selective detection of cis P-tau among non-specific targets like trans P-tau and major plasma proteins. A wide concentration range (10 × 10^-14 M-3.0 × 10^-9 M) of cis P-tau was measured in PBS and human serum matrices with a limit of detection of 0.02 and 0.05 pM, respectively. Clinical applicability of the immunosensor was suggested by its long-term storage stability and successful detection of cis P-tau in real samples of cerebrospinal fluid (CSF) and blood serum collected from human patients at different stages of AD. These results suggest that this simple immunosensor may find great application in clinical settings for early detection of AD which is an unmet urgent need in today's healthcare services.

Chemical Labeling and Enrichment of Histone Glyoxal Adducts

Because of their long half-lives and highly nucleophilic tails, histones are particularly susceptible to accumulating nonenzymatic covalent modifications, such as glycation. The resulting modifications can have profound effects on cellular physiology due to the regulatory role histones play in all DNA-templated processes; however, the complexity of Maillard chemistry on proteins makes tracking and enriching for glycated proteins a challenging task. Here, we characterize glyoxal (GO) modifications on histones using quantitative proteomics and an aniline-derived GO-reactive probe. In addition, we leverage this chemistry to demonstrate that the glycation regulatory proteins DJ-1 and GLO1 reduce levels of histone GO adducts. Finally, we employ a two-round pull-down method to enrich histone H3 GO glycation and map these adducts to specific chromatin regions.

A Review of Electrochemical Sensors for the Detection of Glycated Hemoglobin

Glycated hemoglobin (HbA1c) is the gold standard for measuring glucose levels in the diagnosis of diabetes due to the excellent stability and reliability of this biomarker. HbA1c is a stable glycated protein formed by the reaction of glucose with hemoglobin (Hb) in red blood cells, which reflects average glucose levels over a period of two to three months without suffering from the disturbance of the outside environment. A number of simple, high-efficiency, and sensitive electrochemical sensors have been developed for the detection of HbA1c. This review aims to highlight current methods and trends in electrochemistry for HbA1c monitoring. The target analytes of electrochemical HbA1c sensors are usually HbA1c or fructosyl valine/fructosyl valine histidine (FV/FVH, the hydrolyzed product of HbA1c). When HbA1c is the target analyte, a sensor works to selectively bind to specific HbA1c regions and then determines the concentration of HbA1c through the quantitative transformation of weak electrical signals such as current, potential, and impedance. When FV/FVH is the target analyte, a sensor is used to indirectly determine HbA1c by detecting FV/FVH when it is hydrolyzed by fructosyl amino acid oxidase (FAO), fructosyl peptide oxidase (FPOX), or a molecularly imprinted catalyst (MIC). Then, a current proportional to the concentration of HbA1c can be produced. In this paper, we review a variety of representative electrochemical HbA1c sensors developed in recent years and elaborate on their operational principles, performance, and promising future clinical applications.

Sedentary Behavior Counseling Intervention in Aging People With Type 2 Diabetes: A Feasibility Study

This study examined the feasibility and effect of sedentary behavior (SB) counseling on total sitting time (TST) and glycemic control in people with type 2 diabetes (T2D). Community-dwelling sedentary adults with T2D (n = 10; 8 women; age 65.6 ± 7.31) completed SB counseling (motivational interviewing-informed education about SB) aided by an activity monitor with a vibrotactile feature (activPAL3TM). The monitor was worn for 7 days, on weeks 1 and 13 (without the vibrotactile feature) and during weeks 5 and 9 (with the vibrotactile feature). Intervention feasibility was determined by study retention rates and activity monitor tolerability, and differences between pre- and post-intervention average daily TST. Paired t-test were performed. The effect size (ES) was calculated using Cohen d. All participants attended all study sessions with only 20% reporting moderate issues tolerating the activity monitor. TST time decreased from 11.8 hours ± 1.76 at baseline to 10.29 hours ± 1.84 at 3 months’ assessment (P < .05) with a large ES (Cohen d = .88). HbA1c was decreased by 0.51% (P < .05) at the end of the intervention. This study found that the intervention was feasible for sedentary adults with type 2 diabetes.

Association of Glycosylated Hemoglobin A1c Level With Sudden Sensorineural Hearing Loss: A Prospective Study

Glycosylated hemoglobin A1c (HbA1c) level has strong relevance to microvascular disorders, which are also thought to be the current main aspect of sudden sensorineural hearing loss (SSNHL), so we aim to elucidate the association of the HbA1c level with the severity, types, and prognosis of SSNHL. In this study, comparative analyses based on propensity score matching of the severity, types, and prognosis of SSNHL with the HbA1c level in 116 patients diagnosed as SSNHL were conducted, where they were divided into diabetes mellitus (DM) group and non-DM group. We finally found that, among patients with SSNHL, diabetic patients had a higher HbA1c level, more severe hearing loss, and poorer prognosis than non-diabetic patients. The HbA1c level was found to be significantly correlated with the severity and types of SSNHL, while no strong relevance was found between the higher HbA1c level and the poorer prognosis of SSNHL.

The Interaction between Hb A1C and Selected Genetic Factors in the African American Population in the USA

BACKGROUND

The global prevalence of diabetes mellitus has been growing in recent decades and the complications of longstanding type 2 diabetes continue to place a burden on healthcare systems. The hemoglobin A1c (Hb A1c) content of the blood is used to assess an individual's degree of glycemic control averaged over 2 to 3 months. In the USA, diabetes is the seventh leading cause of death. Black, indigenous, people of color (BIPOC) are disproportionately affected by diabetes compared to non-Hispanic whites. There are many reports of interaction of Hb A1c and hematologic conditions that have a high prevalence in the Black population; some of these effects are contradictory and not easily explained. This review attempts to document and categorize these apparently disparate effects and to assess any clinical impact.

METHODS

Hb A1C can be determined by a variety of techniques including cation-exchange chromatography, electrophoresis, immunoassays, and affinity chromatography. The amount of Hb A1c present in a patient specimen depends not only on blood glucose but is strongly influenced by erythrocyte survival and by structural variations in the globin chains. Sickling hemoglobinopathies are well-represented in the USA in African Americans and the effects of these hemoglobin disorders as well as G6PD deficiency is examined.

CONCLUSION

Hb A1c measurement should always be performed with a cautious approach. The laboratory scientist should be aware of possible pitfalls in unquestioningly determining Hb A1c without a consideration of hematologic factors, both inherited and acquired. This presents a challenge as often times, the laboratory is not aware of the patient's race.

Insulin sensitivity predicts cognitive decline in individuals with prediabetes

INTRODUCTION

Epidemiological studies indicate an association between type 2 diabetes and cognitive dysfunction that appear to start already in the prediabetic state. Although cross-sectional studies have linked insulin resistance to impaired cognition, the potential predictive value of insulin resistance has not yet been sufficiently studied longitudinally without confounding by overt diabetes (and its pharmacological treatment).

RESEARCH DESIGN AND METHODS

We investigated longitudinal data from participants of the 'Tübinger Evaluation of Risk Factors for Early Detection of Neurodegeneration' Study. Subjects underwent a neurocognitive assessment battery (CERAD Plus battery; Consortium to Establish a Registry for Alzheimer's Disease) at baseline and followed every 2 years (median follow-up 4.0 Q1-3: 2.2-4.3 years). Subjects within a pre-diabetic glycated hemoglobin range of 5.6%-6.5% underwent 5-point 75 g oral glucose tolerance tests (OGTTs) with assessment of insulin sensitivity and insulin secretion (n=175). Subjects with newly diagnosed diabetes mellitus or with major depressivity (Beck Depression Inventory >20) were excluded (n=15). Data were analyzed by mixed models using sex, age and glycemic trait as fixed effects. Subject and time since first measurement were used as random effects.

RESULTS

Insulin sensitivity was positively associated with the CERAD sum score (higher is better) in a time-dependent manner (p=0.0057). This result is mainly driven by a steeper decrease in the memory domain associated with lower insulin sensitivity (p=0.029). The interaction between age and insulin sensitivity was independent of glycemia (p=0.02). There was also no association between insulin secretion and cognition.

CONCLUSIONS

Insulin resistance rather than sole elevation of blood glucose predicts cognitive decline, specifically in the memory domain, in persons with prediabetes. Treatments of diabetes that improve insulin sensitivity might therefore have the potential to postpone or even prevent cognitive decline in patients with diabetes.

Is HbA1c an ideal biomarker of well-controlled diabetes?

HbA1c is a biomarker with a central role in the diagnosis and follow-up of patients with diabetes, although not a perfect one. Common comorbidities encountered in patients with diabetes mellitus, such as renal insufficiency, high output states (iron deficiency anaemia, haemolytic anaemia, haemoglobinopathies and pregnancy) and intake of specific drugs could compromise the sensitivity and specificity of the biomarker. COVID-19 pandemic poses a pressing challenge for the diabetic population, since maintaining optimal blood glucose control is key to reduce morbidity and mortality rates. Alternative methods for diabetes management, such as fructosamine, glycosylated albumin and device-based continuous glucose monitoring, are discussed.

The effects of cognitive behavioral therapy for insomnia in people with type 2 diabetes mellitus, pilot RCT part II: diabetes health outcomes

BACKGROUND

Previous studies have shown the negative impact of sleep disturbances, specifically insomnia symptoms, on glucose metabolism for people with type 2 diabetes (T2D). People with insomnia symptoms are at risk of poor glycemic control and suboptimal diabetes self-care behavior (DSCB). Investigating the impact of a safe and effective intervention for individuals with T2D and insomnia symptoms on diabetes' health outcomes is needed. Therefore, the aim of this exploratory study is to examine the effects of Cognitive Behavioral Therapy for Insomnia (CBT-I) on glycemic control, DSCB, and fatigue.

METHODS

Twenty-eight participants with T2D and insomnia symptoms, after passing an eligibility criteria at a medical research center, were randomly assigned to CBT-I (n = 14) or Health Education (HE; n = 14). The CBT-I and HE groups received 6 weekly one-hour sessions. This Randomized Controlled Trial (RCT) used a non-inferiority framework to test the effectiveness of CBT-I. Validated assessments were administered at baseline and post-intervention to assess glycemic control, DSCB, and fatigue. A Wilcoxon signed-rank test was utilized to compare within-group changes from baseline to post-intervention. A Mann-Whitney test was utilized to measure the between-group differences. Linear regression was used to assess the association between the blood glucose level and the number of days in the CBT-I group.

RESULTS

The recruitment duration was from October 2018 to May 2019. A total of 13 participants completed the interventions in each group and are included in the final analysis. No adverse events, because of being a part of this RCT, were reported. CBT-I participants showed significantly greater improvement in glycemic control, DSCB, and fatigue. There was a significant association between the number of days in the CBT-I intervention with the blood glucose level before bedtime (B = -0.56, p = .009) and after awakening in the morning (B = -0.57, p = .007).

CONCLUSIONS

This study demonstrated a clinically meaningful effect of CBT-I on glycemic control in people with T2D and insomnia symptoms. Also, CBT-I positively impacted daytime functioning, including DSCB and fatigue. Future research is needed to investigate the long-term effects of CBT-I on laboratory tests of glycemic control and to understand the underlying mechanisms of any improvements.

TRIAL REGISTRATION

Clinical Trials Registry ( NCT03713996 ). Retrospectively registered on 22 October 2018.

Recent Trends in Electrochemical Sensors for Vital Biomedical Markers Using Hybrid Nanostructured Materials

This work provides a succinct insight into the recent developments in electrochemical quantification of vital biomedical markers using hybrid metallic composite nanostructures. After a brief introduction to the biomarkers, five types of crucial biomarkers, which require timely and periodical monitoring, are shortlisted, namely, cancer, cardiac, inflammatory, diabetic and renal biomarkers. This review emphasizes the usage and advantages of hybrid nanostructured materials as the recognition matrices toward the detection of vital biomarkers. Different transduction methods (fluorescence, electrophoresis, chemiluminescence, electrochemiluminescence, surface plasmon resonance, surface-enhanced Raman spectroscopy) reported for the biomarkers are discussed comprehensively to present an overview of the current research works. Recent advancements in the electrochemical (amperometric, voltammetric, and impedimetric) sensor systems constructed with metal nanoparticle-derived hybrid composite nanostructures toward the selective detection of chosen vital biomarkers are specifically analyzed. It describes the challenges involved and the strategies reported for the development of selective, sensitive, and disposable electrochemical biosensors with the details of fabrication, functionalization, and applications of hybrid metallic composite nanostructures.

An Azidoribose Probe to Track Ketoamine Adducts in Histone Ribose Glycation

Reactive cellular metabolites can modify macromolecules and form adducts known as nonenzymatic covalent modifications (NECMs). The dissection of the mechanisms, regulation, and consequences of NECMs, such as glycation, has been challenging due to the complex and often ambiguous nature of the adducts formed. Specific chemical tools are required to directly track the formation of these modifications on key targets in order to uncover their underlying physiological importance. Here, we present the novel chemoenzymatic synthesis of an active azido-modified ribose analog, 5-azidoribose (5-AR), as well as the synthesis of an inactive control derivative, 1-azidoribose (1-AR), and their application toward understanding protein ribose-glycation in vitro and in cellulo. With these new probes we found that, similar to methylglyoxal (MGO) glycation, ribose glycation specifically accumulates on histones. In addition to fluorescent labeling, we demonstrate the utility of the probe in enriching modified targets, which were identified by label-free quantitative proteomics and high-resolution MS/MS workflows. Finally, we establish that the known oncoprotein and hexose deglycase, fructosamine 3-kinase (FN3K), recognizes and facilitates the removal of 5-AR glycation adducts in live cells, supporting the dynamic regulation of ribose glycation as well as validating the probe as a new platform to monitor FN3K activity. Altogether, we demonstrate this probe's utilities to uncover ribose-glycation and deglycation events as well as track FN3K activity toward establishing its potential as a new cancer vulnerability.

Relationship between hemoglobin A1c and serum troponin in patients with diabetes and cardiovascular events

Objectives

Diabetes mellitus is a group of metabolic disorders associated with high risk for cardiovascular disease. Although troponins are primarily clinically used for the diagnosis of acute coronary syndrome, they are also used in risk assessment in patients with acute coronary syndrome as well as in a number of other conditions. The aim of this review was to investigate the relationship between hemoglobin A1c and serum troponin in patients with diabetes and cardiovascular events.

Methods

Hemoglobin A1_c has been chosen as the best clinical indicator of glucose control and risk of micro and macrovascular complications. We investigated cardiac troponins as a group of markers of muscle injury which includes troponin T, troponin I and troponin C. Troponin T and I are specific for myocardial injury, compared to C which is specific for skeletal muscle.

Results

In this review, we showed that there was a causal relation between hemoglobin A1_c levels and serum troponin concentrations. Hemoglobin A1_c has shown to be a positive predictive factor of incidence, mortality and morbidity of conditions such as acute coronary syndrome, arrhythmias, stroke, pulmonary embolism and other conditions that causes troponin elevation by its release in circulation.

Conclusions

Chronic hyperglycemia decreases glomerular filtration and consequently decreases troponin elimination and also by affecting the heart microcirculation it leads to microvascular damage and consequently to ischemia which contribute to troponin concentration elevation. Furthermore, correlation between hemoglobin A1_c and troponin concentration manifests in their prognostic value for mortality.

Factors associated with glycemic control in community-dwelling elderly individuals with type 2 diabetes mellitus in Zhejiang, China: a cross-sectional study

BACKGROUND

Although exercise seems to be beneficial for type 2 diabetes mellitus (T2DM) patients, there is limited research elucidating the optimal accessible indices of adiposity and insulin resistance for identifying elderly T2DM patients with poor glycemic control, which could be improved by performing regular exercise.

METHODS

A community-based, cross-sectional study was conducted with 918 Chinese elderly individuals with T2DM in Zhejiang. Relevant risk factors for poor glycemic control, as determined using glycated haemoglobin A1c (HbA1c) > 7%, were explored using logistic regression analyses and included body mass index (BMI), waist circumference (WC), waist to height ratio (WHtR), fasting blood glucose (FBG), triglycerides (TGs), total cholesterol (TC), the product of fasting triglycerides and glucose (TyG), visceral adiposity index (VAI), lipid accumulation product (LAP), TyG-BMI, and TyG-WC. Comparisons of the risk factors' ability to discriminate poor glycemic control as well as their optimal cutoff values were determined using receiver operating characteristic (ROC) analyses, and then the extent of poor glycemic control risk reduction through regular exercise was examined using multivariate logistic regression analyses.

RESULTS

The overall poor glycemic control rate was 49.3%. The factors associated with poor glycemic control included FBG > 3.869, TyG > 8.73, TyG-BMI > 222.45, and TyG-WC > 713.48 in logistic regression analyses. The optimal cutoff points of FBG, TyG, TyG-WC, and TyG-BMI in discriminating poor glycemic control were 7.38, 9.22, 813.33, and 227.77, and their corresponding areas under the ROC curves were 0.864(0.840-0.886), 0.684(0.653-0.714), 0.604(0.571-0.635), and 0.574(0.541-0.606), respectively. Occasional and regular exercise reduced the odds ratios (95% confidence interval) of poor glycemic control to 0.187 (0.063-0.557) and 0.183 (0.059-0.571) for subjects with TyG-WC > 813.33 (p = 0.008), to 0.349 (0.156-0.782) and 0.284 (0.123-0.652) for subjects with TyG > 9.22 (p = 0.011), and to 0.390 (0.175-0.869) and 0.300(0.130-0.688) for subjects with TyG-BMI > 227.77 (p = 0.017), respectively, after adjusting for multiple confounding factors.

CONCLUSION

Among elderly individuals with T2DM, poor glycemic control risk might be identified using indices calculated from FBG, TG, BMI, and WC measurements, which are indicative of adiposity and insulin resistance. TyG-WC seems to be an accessible and useful indicator to identify which elderly T2DM patients would benefit from performing regular exercise to achieve good glycemic control.

Gold nano-flowers (Au NFs) modified screen-printed carbon electrode electrochemical biosensor for label-free and quantitative detection of glycated hemoglobin

Glycated hemoglobin (HbA1c) represents the average glucose level over the past three months and has been considered as the most important biomarker for the diagnosis of Type Ⅱ diabetes (T2D). Herein, a label-free and quantitative electrochemical biosensor based on 4-mercaptophenylboronic acid (4-MPBA) modified gold nano-flowers (Au NFs) substrate was developed for the determination of HbA1c. Under optimal conditions, the linear dynamic ranges of HbA1c (5 μg/mL - 1000 μg/mL) and HbA1c% (2%-20%) by cyclic voltammetry were achieved. The electrochemical biosensor showed great detection specificity towards HbA1c and relatively stability after storage at 4 °C. This method could also be applied in human serum system which holds great potential to be applied to monitor real blood samples of diabetes patients. In human serum system, the recovery rate could reach 103.8% and 99.0%. It could achieve fast detection, the total analysis time was less than 65 min, and the detection time was less than 10 s. Moreover, in terms of fabrication process, operation procedure, detection time and cost, this technique was superior to the current HbA1c detection methods suggesting great promise for the practical clinical use in the future.

Reversible histone glycation is associated with disease-related changes in chromatin architecture

Cellular proteins continuously undergo non-enzymatic covalent modifications (NECMs) that accumulate under normal physiological conditions and are stimulated by changes in the cellular microenvironment. Glycation, the hallmark of diabetes, is a prevalent NECM associated with an array of pathologies. Histone proteins are particularly susceptible to NECMs due to their long half-lives and nucleophilic disordered tails that undergo extensive regulatory modifications; however, histone NECMs remain poorly understood. Here we perform a detailed analysis of histone glycation in vitro and in vivo and find it has global ramifications on histone enzymatic PTMs, the assembly and stability of nucleosomes, and chromatin architecture. Importantly, we identify a physiologic regulation mechanism, the enzyme DJ-1, which functions as a potent histone deglycase. Finally, we detect intense histone glycation and DJ-1 overexpression in breast cancer tumors. Collectively, our results suggest an additional mechanism for cellular metabolic damage through epigenetic perturbation, with implications in pathogenesis.

Appropriateness of Using Tests for Blood Glucose and Diabetic Complications in Clinical Practice: Experiences in a Hospital in Thailand

BACKGROUND This study aimed to evaluate how the tests for blood glucose (BG) and diabetic complications have been utilized in a hospital in Thailand. MATERIAL AND METHODS Patient medical records having the results of BG, HbA1c, and/or urine microalbumin presented and the records of DM patients having the results of serum lipids, serum LDL-C, and/or serum creatinine presented were selected. The data of diagnosis, ordered tests, and testing results in these records were extracted for evaluation. RESULTS This study recruited 1066 patients diagnosed with DM and 3081 patients diagnosed with other diseases. Point-of-care testing (POCT) for BG was repeatedly used in 371 non-DM cases; most of its results were normal. The results of BG and HbA1c were often used together. There was a good relationship between them, and these test results indicated poor glycemic control in 58% of DM cases. In non-DM cases, the test results agreed, indicating normoglycemia in 17.32%, pre-diabetes in 20.47%, and diabetes in 21.78%. To prevent diabetic nephropathy, serum creatinine was frequently used, whereas urine microalbumin, the recommended test, was underutilized. The result of LDL-C from both direct measurement and calculation were used; however, based on the same guidelines, the results of measured LDL-C indicated risk of cardiovascular diseases in a higher percentage of DM cases than did the results of calculated LDL-C. CONCLUSIONS The use of POCT for BG in hospitalized patients may be inappropriate. The utilization of urine microalbumin should be promoted to effectively prevent diabetic nephropathy.

Fluorescent 2D WS2 Nanosheets Bearing Chemical Affinity Elements for the Recognition of Glycated Hemoglobin

It is required to exfoliate and functionalize 2D transition metal dichalcogenides (TMDs) in an aqueous solution for biological and medical applications. Herein, the approach for the simultaneous exfoliation and functionalization of 2D WS₂ nanosheets using boronic acid-modified poly(vinyl alcohol) (B-PVA) in an aqueous solution is reported, and the B-PVA-functionalized WS₂ nanosheets (B-PVA-WS₂ ) are exploited as a fluorescent biosensor for the detection of glycated hemoglobin, HbA1c. The synthetic B-PVA polymer facilitates the exfoliation and functionalization of WS₂ nanosheets from the bulk counterpart in the aqueous solution via a pulsed sonication process, resulting in fluorescent B-PVA-WS₂ nanohybrids with a specific recognition of HbA1c. The fluorescence of the B-PVA-WS₂ is quenched in the presence of HbA1c, whereas PVA-functionalized WS₂ (PVA-WS₂ ), not bearing boronic acid as a recognition moiety, shows no fluorescence changes upon the addition of the target. The B-PVA-WS₂ is able to selectively detect HbA1c at the concentration as low as 3.3 × 10^-8 m based on its specific fluorescence quenching.

Current Status of HbA1c Biosensors

Glycated hemoglobin (HbA1c) is formed via non-enzymatic glycosylation reactions at the α–amino group of βVal1 residues in the tetrameric Hb, and it can reflect the ambient glycemic level over the past two to three months. A variety of HbA1c detection methods, including chromatography, immunoassay, enzymatic measurement, electrochemical sensor and capillary electrophoresis have been developed and used in research laboratories and in clinics as well. In this review, we summarize the current status of HbA1c biosensors based on the recognition of the sugar moiety on the protein and also their applications in the whole blood sample measurements.

Impact of HbA1c Testing at Point of Care on Diabetes Management

Diabetes is a highly prevalent disease also implicated in the development of several other serious complications like cardiovascular or renal disease. HbA1c testing is a vital step for effective diabetes management, however, given the low compliance to testing frequency and, commonly, a subsequent delay in the corresponding treatment modification, HbA1c at the point of care (POC) offers an opportunity for improvement of diabetes care. In this review, based on data from 1999 to 2016, we summarize the evidence supporting a further implementation of HbA1c testing at POC, discuss its limitations and propose recommendations for further development.

Boronate-functionalized hydrogel as a novel biosensing interface for the glycated hemoglobin A1c (HbA1c) based on the competitive binding with signaling glycoprotein

According to recent increases in public healthcare costs associated with diabetes mellitus, the development of new glycemic monitoring techniques based on the biosensing of glycated hemoglobin A1c (HbA_1c), a promising long-term glycemic biomarker, has become a major challenge. In the development of HbA_1c biosensors for point-of-care applications, the selection of an effective biorecognition layer that provides a high reaction yield and specificity toward HbA_1c is regarded as the most significant issue. To address this, we developed a novel HbA_1c biosensing interfacial material by the integration of boronate hydrogel with glass fiber membrane. In the present study, a new boronate-functionalized hydrogel was designed and spatio-selectively photopolymerized on a hydrophilic glass fiber membrane by using N-hydroxyethyl acrylamide, 3-(acrylamido)phenylboronic acid, and bis(N,N'-methylene-bis-acrylamide). Using this approach, the boronic acid group, which specifically recognizes the cis-diol residue of glucose on the HbA_1c molecule, can be three-dimensionally coated on the surface of the glass fiber network with a high density. Because this network structure of boronate hydrogel-grafted fibers enables capillary-driven fluid control, facile HbA_1c biosensing in a lateral flow assay concept could be accomplished. On the proposed HbA_1c biosensing interface, various concentrations of HbA_1c (5-15%) in blood-originated samples were sensitively measured by a colorimetric assay using horseradish peroxidase, a glycoenzyme can generate chromogenic signal after the competitive binding against HbA_1c to the boronic acid residues. Based on the demonstrated advantages of boronate hydrogel-modified membrane including high analytical performance, easy operation, and cost-effectiveness, we expect that the proposed biorecognition interfacial material can be applied not only to point-of-care HbA_1c biosensors, but also to the quantitative analysis of other glycoprotein biomarkers.

Recent Progress in Electrochemical Biosensors for Glycoproteins

This review provides an overview of recent progress in the development of electrochemical biosensors for glycoproteins. Electrochemical glycoprotein sensors are constructed by combining metal and carbon electrodes with glycoprotein-selective binding elements including antibodies, lectin, phenylboronic acid and molecularly imprinted polymers. A recent trend in the preparation of glycoprotein sensors is the successful use of nanomaterials such as graphene, carbon nanotube, and metal nanoparticles. These nanomaterials are extremely useful for improving the sensitivity of glycoprotein sensors. This review focuses mainly on the protocols for the preparation of glycoprotein sensors and the materials used. Recent improvements in glycoprotein sensors are discussed by grouping the sensors into several categories based on the materials used as recognition elements.

Recent progress in electrochemical biosensors based on phenylboronic acid and derivatives

This review provides an overview of recent progress made in the development of electrochemical biosensors based on phenylboronic acid (PBA) and its derivatives. PBAs are known to selectively bind 1,2- and 1,3-diols to form negatively charged boronate esters in neutral aqueous media and have been used to construct electrochemical glucose sensors because of this selective binding. PBA-modified metal and carbon electrodes have been widely studied as voltammetric and potentiometric glucose sensors. In some cases, ferroceneboronic acid or ferrocene-modified phenylboronic acids are used as sugar-selective redox compounds. Another option for sensors using PBA-modified electrodes is potentiometric detection, in which the changes in surface potential of the electrodes are detected as an output signal. An ion-sensitive field effect transistor (FET) has been used as a signal transducer in potentiometric sensors. Glycoproteins, such as glycated hemoglobin (HbA1c), avidin, and serum albumin can also be detected by PBA-modified electrodes because they contain hydrocarbon chains on the surface. HbA1c sensors are promising alternatives to enzyme-based glucose sensors for monitoring blood glucose levels over the preceding 2-3months. In addition, PBA-modified electrodes can be used to detect a variety of compounds including hydroxy acids and fluoride (F(-)) ions. PBA-based F(-) ion sensors may be useful if reagentless sensors can be developed.

Automatic laboratory-based strategy to improve the diagnosis of type 2 diabetes in primary care

Introduction

To study the pre-design and success of a strategy based on the addition of hemoglobin A1c (HbA1c) in the blood samples of certain primary care patients to detect new cases of type 2 diabetes.

Materials and methods

In a first step, we retrospectively calculated the number of HbA1c that would have been measured in one year if HbA1c would have been processed, according to the guidelines of the American Diabetes Association (ADA). Based on those results we decided to prospectively measure HbA1c in every primary care patient above 45 years, with no HbA1c in the previous 3 years, and glucose concentration between 5.6-6.9 mmol/L, during an 18 months period. We calculated the number of HbA1c that were automatically added by the LIS based on our strategy, we evaluated the medical record of such subjects to confirm whether type 2 diabetes was finally confirmed, and we calculated the cost of our intervention.

Results

In a first stage, according to the guidelines, Hb1Ac should have been added to the blood samples of 13,085 patients, resulting in a cost of 14,973€. In the prospective study, the laboratory added Hb1Ac to 2092 patients, leading to an expense of 2393€. 314 patients had an HbA1c value ≥ 6.5% (48 mmol/mol). 82 were finally diagnosed as type 2 diabetes; 28 thanks to our strategy, with an individual cost of 85.4€; and 54 due to the request of HbA1c by the general practitioners (GPs), with a cost of 47.5€.

Conclusion

The automatic laboratory-based strategy detected patients with type 2 diabetes in primary care, at a cost of 85.4€ per new case.

Standardising HbA1c-based diabetes diagnosis: opportunities and challenges

Globally, the incidence of diabetes mellitus is rising at an alarming rate and has become a health crisis that threatens the economies of all nations. Therefore, diagnosing diabetes has become an important issue in the management of diabetes. Glycated hemoglobin (HbA1c) is now recommended as a means to diagnose diabetes, but its use still has limitations. In this article, the biology, measurement, standardization, and opportunities and challenges of the use of HbA1c to diagnose diabetes are reviewed. More specifically, its use in China and the Asian region is discussed in detail.

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.