Glycated Hemoglobin (HbA1c): Clinical Applications of a Mathematical Concept

Continuous Glucose Monitoring Alarms in Adults with Type 1 Diabetes: User Characteristics and the Impact of Hypoglycemia and Hyperglycemia Alarm Thresholds on Glycemic Control

Background: Few studies have evaluated the implications of the alarm thresholds of continuous glucose monitoring (CGM) systems for individuals with diabetes. The present study aimed to investigate the influence of hypoglycemia and hyperglycemia alarm thresholds on glycemic control in adults with type 1 diabetes (T1DM) and the characteristics of patients who use these alarms more frequently. Methods: This observational cross-sectional study included 873 users of the FreeStyle Libre 2 system (501 men, median age 48 years, range 18-90 years) with T1DM from a single center. We investigated the role of demographic and metabolic factors on the use of alarms and the impact of hypoglycemia and hyperglycemia alarms and their thresholds on glycemic control. Results: Alarm users were older than nonusers (median age 49 vs. 43 years, respectively; P < 0.001). The hypoglycemia alarms were set by 76.1% of women and by 69.1% of men (P = 0.022). The hypoglycemia alarms reduced hypoglycemia features and glucose variability, although at the expense of shorter time in range. The higher the hypoglycemia alarm threshold, the greater these effects. The hyperglycemia alarms were effective in reducing hyperglycemia and lowering the glucose management indicator, although at the expense of a greater tendency to hypoglycemia. The lower the hyperglycemia alarm threshold, the greater these effects. Conclusions: CGM alarms contribute to better glycemic control. However, hypoglycemia and hyperglycemia alarms have advantages and disadvantages. Adults with T1DM should explore, under medical supervision, which alarm thresholds will best help them achieve their individual glycemic goals.

Clinical Risk Assessment and Comparison of Bias between Laboratory Methods for Estimation of HbA1c for Glycated Hemoglobin in Hyperglycemic Patients

INTRODUCTION

Hemoglobin A1c (HbA1c), also known as glycated hemoglobin, is a blood test used to evaluate and track a patient's blood sugar levels over the previous 2-3 months. We have compared the analytical performance of the D10 hemoglobin (HPLC) testing system to that of the immunoturbidimetric technique, which is a light-scattering immunoassay.

OBJECTIVES

To assess the clinical risk assessment between two methods (Compare the two Immunoturbidometric methods (AU680) vs. HPLC method (D10)) in hyperglycemic patients and assess the acceptability of the respective methods in the Clinical biochemistry laboratory.

METHODS

The charge of the globins in Hb was used as the basis for the HPLC method used to measure HbA1c. HPLC detects and quantifies even the tiniest Hb fractions and the full spectrum of Hb variants. HbA1c was measured using the immunoturbidimetric (AU 680 Beckmann coulter analyzer) and high-performance liquid chromatography (HPLC) techniques. Experiments also made use of immunoturbidimetric techniques (using an AU 680 Beckmann coulter analyzer equipment).

RESULTS

There is no statistically significant difference in HbA1c readings between male and female patients, as measured by either the Immunoturbidimetric or HPLC techniques.

CONCLUSION

The immunoturbidimetric and high-performance liquid chromatography techniques for estimating HbA1c yielded identical results. From the results of this study, we may deduce that both techniques are valid for estimating HbA1c. As a result, it may be suggested that both approaches can be used to estimate HbA1c in diabetic individuals.

Multi-level Analysis of HbA1c in Diagnosis and Prognosis of Diabetic Patients

BACKGROUND

Type 2 diabetes (T2D), a multifaceted metabolic disorder, may cause health tribulations and changes in biochemical blood markers. Other research has examined the relationships between several biomarkers and the risk of T2D. Few studies have examined the relationships between these biomarkers and potential changes to the network of biomarkers associated with diabetes.

METHOD

Glycated hemoglobin, or HbA1c, is used to evaluate and track the blood glucose history throughout the previous two to three months of testing. The ability to reflect the cumulative glycemic history of the previous two to three months makes HbA1c an essential biomarker of long-term glycemic control. HbA1c offers a trustworthy indicator of chronic hyperglycemia and strongly correlates with the likelihood of long-term consequences from diabetes.

RESULT

Additionally, elevated HbA1c has been recognized as a stand-alone risk factor for patients with and without diabetes developing coronary heart disease and stroke. One HbA1c test offers a wealth of information that makes it a reliable biomarker for the diagnosis and prognosis of diabetes. A clinical examination may be required to establish the connection between diabetes, prediabetes, biochemical blood indicators, age, and body mass index (BMI).

CONCLUSION

We observed that diabetes, BMI, age, HbA1c, cholesterol, triglycerides, LDL, VLDL, and HDL were all linked using multivariate analysis.

Impact of Uncontrolled Diabetes Mellitus on Blood Cells Indices and Plasma Components in Patients Without Nephropathy

<b>Background and Objective:</b> Diabetes mellitus (DM) the most prevalent consequences are diabetic retinopathy, neuropathy, cardiovascular illnesses, erectile dysfunctions, stroke and cardiovascular difficulties. The main goal of this study was to evaluate the impact of uncontrolled diabetes mellitus on blood cells' indices and plasma components. <b>Materials and Methods:</b> This is a prospective cross-sectional study. The research was carried out at the King Fahad Medical Center in Riyadh, in duration from February, 2023 to May, 2023, in the interest of healthcare consumers attending the hematology laboratory for routine investigations. Sixty samples were collected and complete blood count, lipid profile, HbA1c and blood glucose for blood samples. <b>Results:</b> In this study, females accounted for 53.3% of the participants, while males accounted for 46.7%. In terms of age distribution, more than 55 years old accounted for 50% of the study's participants. A significant correlation has been found between HbA1c and red blood cell Mean Cell Volume (MCV) and there was a significant association between the high level of HbA1c and the red blood count. However, there was no significant correlation between plasma components and HbA1c. <b>Conclusion:</b> There is a remarkable effect of uncontrolled diabetes mellitus and RBCs count and erythrocyte MCV.

Biomarkers and their Clinical Applications in Pediatrics

Biomarker studies are becoming increasingly interesting for many fields of medicine. The use of biomarkers in medicine is involved in detecting diseases and supporting diagnosis and treatment decisions. New research and new discoveries on the molecular basis of the disease show that there may be a number of promising new biomarkers for use in daily clinical practice. Clinical trials in children lag behind adult research both in quality and quantity. The number of biomarkers validated to optimize pediatric patient management is limited. In the pathogenesis of many diseases, it should not be extrapolated to the pediatric clinical setting, taking into account that biomarkers that are effective in adults are clearly different in children and that ontogeny directly affects disease development and therapeutic response in children. The search for ideal biomarkers or markers that can make an early and definitive diagnosis in neonatal sepsis is still ongoing. The ideal biomarker for pediatric diseases should be costeffective, noninvasive, applicable to pediatric specific diseases, and its results should correspond to age-related physiological changes. Lactate, troponin and B-type natriuretic peptide are valuable biomarkers in the evaluation and management of critically ill children with cardiac disease. Tumor markers in children are biochemical substances used in the clinical treatment of pediatric tumors and to detect the presence of cancer (regression or progression). In this chapter, current and brief information about biomarkers and their clinical applications used in the diagnosis and monitoring of pediatric diseases is presented.;

Effect of iron deficiency anaemia over glycated hemoglobin in non-diabetic women

BACKGROUND

Glycated hemoglobin (HbA1c) is a form of hemoglobin bound to glucose and used as an index of glycaemic control reflecting glucose levels of the previous three months. Iron deficiency anemia (IDA) is the commonest form of anemia that affects HbA1c. Reports on the effects of IDA on HbA1c levels are inconsistent in India. Therefore, the study correlated the HbA1c and IDA in non-diabetic female patients.

METHODS

A correlative study between HbA1c and IDA was carried out at the Department of Biochemistry, A. J. Institute of Medical Sciences, Mangaluru, India. A total of 50 non-diabetic female patients, aged between 20-50 years, with decreased levels of Hb, MCV and MCHC were selected. Their ferritin levels were determined by ELISA method to confirm IDA. Forty confirmed iron-deficient samples whose serum ferritin levels were <90 pg/dL, were tested for HbA1c levels by nephelometry method.

RESULTS

HbA1c correlated positively with serum ferritin, Hb, MCV, MCH and MCHC (P<0.05). There was a significant decrease in mean value of HbA1c in those with severe anemia (4.50±0.34) compared to those with moderate anemia (5.18±0.35) (P<0.001).

CONCLUSION

Results showed positive correlation of HbA1c with ferritin and hemoglobin. Therefore, iron status should be considered during the interpretation of the HbA1c concentrations in diabetes mellitus.

Predicting Glycated Hemoglobin Through Continuous Glucose Monitoring in Real-Life Conditions: Improved Estimation Methods

BACKGROUND

The adoption of continuous glucose monitoring (CGM) already helps to improve glycemic control in diabetes. When coupled with appropriate data analysis techniques, CGM also provides dependable estimates for significant metrics, like glycated hemoglobin (HbA1c). Findings from the REALISM-T1D study can boost HbA1c estimation methods in diabetes care and stimulate their use in clinical practice.

METHODS

Continuous glucose monitoring data of 27 adults affected by type-1 diabetes were acquired by means of G6 (Dexcom, San Diego, CA) sensors for a time span of 120 days. Glycated hemoglobin laboratory assays were performed during the concluding follow-up visits. Data were then analyzed to derive estimates of assay results, taken as the gold standard.

RESULTS

Bland-Altman (BA) plots show that smart interpolation to patch missing data and a wise choice of interstitial glucose (IG) weighting function, besides a proper mean interstitial glucose (MIG) to HbA1c regression equation, improve HbA1c estimation quality with respect to methods relying on MIG alone. A decrease in the BA plot-related variance of differences with respect to the gold standard confirms the improvement. Wilcoxon signed-rank tests on the bias-compensated mean squared error (MSE) with respect to conventional MIG-based methods show that the improvement is statistically significant with a confidence level better than 95% (P = .0179).

CONCLUSIONS

Improved HbA1c estimation methods result in better HbA1c prediction quality with respect to those based on MIG alone, thus providing quick, but still relatively accurate feedback to diabetologists. They alleviate the discordances reported in literature and, with further improvements, may become a viable complement/alternative to HbA1c assays.

Evaluation of Red Blood Cell Parameters as a Biomarker for Long-Term Glycemic Control Monitoring Among Type 2 Diabetic Patients in Southwest Ethiopia: A Cross-Sectional Study

OBJECTIVE

The main aim of this study was to assess red blood cell parameters as a biomarker for long-term glycemic monitoring among T2 DM patients.

METHODS

Facility-based cross-sectional study through a consecutive sampling technique was conducted among 124 T2 DM patients at the chronic illness follow-up clinic of Jimma Medical Center (JMC) from July 27 to August 31, 2020. A structured questionnaire was used to collect socio-demographic and clinical-related data. Five milliliters of the blood specimen were collected from each eligible T2 DM patient. Glycated hemoglobin (HbA1c) and red blood cell parameters were determined by Cobas 6000 and DxH 800 fully automated analyzers, respectively. Data were entered into EpiData software version 3.1 and exported to SPSS 25 version for analysis. Independent t-test and Pearson's correlation coefficient were used to address the research questions. A P-value <0.05 was considered statistically significant.

RESULTS

The mean age of study participants was 51.84± 11.6 years. Moreover, 60.5% of T2 DM patients were in poor glycemic control. There was a significant mean difference between good and poor glycemic controlled T2 DM patients in red blood cell count (4.79±0.5 vs 4.38±0.8), hemoglobin (14.13±1.4 vs 13.60±1.6), mean corpuscular volume (89.52±4.7 vs 92.62±7.5), mean corpuscular hemoglobin (29.63±1.6 vs 30.77±2.9), and red cell distribution width (13.68±1.1 vs 14.63±1.2) respectively. Red blood cell count was inversely correlated (r=-0.280, p=0.002) with HbA1c while mean corpuscular volume (r=0.267, p=0.003), mean corpuscular hemoglobin (r=0.231, p=0.010), and red cell distribution width (r= 0.496, p=0.000) were positively correlated with level of HbA1c.

CONCLUSION

Red cell count, mean corpuscular volume, mean corpuscular hemoglobin, and red cell distribution width could be useful indicators to monitor the glycemic status of T2 DM patients instead of HbA1c, though large prospective studies should be considered.

Faradaic electrochemical impedance spectroscopy for enhanced analyte detection in diagnostics

Electrochemical impedance spectroscopy (EIS) is a widely implementable technique that can be applied to many fields, ranging from disease detection to environmental monitoring. EIS as a biosensing tool allows detection of a broad range of target analytes in point-of-care (POC) and continuous applications. The technique is highly suitable for multimarker detection due to its ability to produce specific frequency responses depending on the target analyte and molecular recognition element (MRE) combination. EIS biosensor development has shown promising results for the medical industry in terms of diagnosis and prognosis for various biomarkers. EIS sensors offer a cost-efficient system and rapid detection times using minimal amounts of sample volumes, while simultaneously not disturbing the sample being studied due to low amplitude perturbations. These properties make the technique highly sensitive and specific. This paper presents a review of EIS biosensing advancements and introduces different detection techniques and MREs. Additionally, EIS's underlying theory and potential surface modification techniques are presented to further demonstrate the technique's ability to produce stable, specific, and sensitive biosensors.

A Novel Earwax Method to Measure Acute and Chronic Glucose Levels

Diabetes is the fourth cause of death globally. To date, there is not a practical, as well as an accurate sample for reflecting chronic glucose levels. We measured earwax glucose in 37 controls. Participants provided standard serum, glycated hemoglobin (HbA1c) and earwax samples at two time-points, one month apart. The specimens measured baseline fasting glucose, a follow-up postprandial glucose level and a between sample chronic glucose, calculated using the average level on the two occasions. The baseline earwax sample was obtained using a clinical method and the follow-up using a novel self-sampling earwax device. The earwax analytic time was significantly faster using the novel device, in comparison to the clinical use of the syringe. Earwax accurately reflected glucose at both assessments with stronger correlations than HbA1c. Follow-up postprandial concentrations were more significant than their respective fasting baseline concentrations, reflecting differences in fasting and postprandial glycemia and more efficient standardization at follow up. Earwax demonstrated to be more predictable than HbA1c in reflecting systemic fasting, postprandial and long-term glucose levels, and to be less influenced by confounders. Earwax glucose measurements were approximately 60% more predictable than HbA1c in reflecting glycemia over a month. The self-sampling device provided a sample that might accurately reflect chronic glycemia.