Serum glycated albumin to haemoglobin A(1C) ratio can distinguish fulminant type 1 diabetes mellitus from type 2 diabetes mellitus

Glucose metabolism and smaller hippocampal volume in elderly people with normal cognitive function

We investigated associations of glycemic measures, and insulin resistance and secretion measures with hippocampal and subfield volumes. In this cross-sectional study, 7400 community-dwelling participants underwent brain MRI and health checkups between 2016 and 2018. Hemoglobin A1c (HbA1c), glycated albumin (GA), homeostasis model assessment for insulin resistance (HOMA-IR), and HOMA of percent β-cell function (HOMA-β) were evaluated. The associations of each measure with a smaller volume of the hippocampus and twelve hippocampal subfields were investigated. As a result, higher HbA1c or GA and lower HOMA-β levels were significantly associated with smaller volumes in multiple hippocampal subfields. Furthermore, even when we analyzed non-diabetic individuals, substantial associations remained between higher GA or lower HOMA-β levels and smaller volumes of the whole hippocampus or the fimbria. Our findings indicate that postprandial glucose fluctuations, postprandial hyperglycemia, and low insulin secretion have a specific effect on the development of smaller hippocampal volume, suggesting that primary prevention of diabetes and/or sufficient glucose control are important for the prevention of dementia.

Usefulness of glycated albumin level as a glycemic index complementing glycosylated hemoglobin in diabetic children and adolescents

PURPOSE

Glycated albumin (GA) is a glycemic marker reflecting the average serum glucose of the previous 2 weeks. This study aimed to evaluate the usefulness of GA as a glycemic index to complement glycosylated hemoglobin (HbA1c) in children and adolescents.

METHODS

Fifty-four children and adolescents with diabetes mellitus (DM) and 97 children and adolescents without DM (NDM) were enrolled. The correlation between mean blood glucose (MG) and GA compared to HbA1c was investigated in the DM group. The correlation between fasting glucose (FG) and GA compared to HbA1c was investigated in the NDM group. Factors affecting GA, HbA1c, and GA/HbA1c were analyzed.

RESULTS

In the DM group, positive correlations were observed between MG and GA (P=0.003), between MG and HbA1c (P=0.001), and between GA and HbA1c (P<0.001). The correlation coefficient between MG and GA did not differ from that between MG and HbA1c in the DM group (P=0.811). Among patients with DM, those whose standardized body mass index standard deviation score (BMI SDS) was ≥2 had a lower GA/HbA1c compared with those whose BMI SDS was <2 (P=0.001). In the NDM group, there were no significant correlations between FG and GA, between FG and HbA1c, or between GA and HbA1c. The NDM subjects whose BMI SDS was ≥2 had a lower GA/HbA1c than did the NDM subjects whose BMI SDS was <2 (P=0.003).

CONCLUSION

GA is comparable with HbA1c in reflecting glycemic control in children and adolescents with DM. GA is affected by obesity in children and adolescents with or without DM.

Analytical Challenges in Diabetes Management: Towards Glycated Albumin Point-of-Care Detection

Diabetes mellitus is a worldwide-spread chronic metabolic disease that occurs when the pancreas fails to produce enough insulin levels or when the body fails to effectively use the secreted pancreatic insulin, eventually resulting in hyperglycemia. Systematic glycemic control is the only procedure at our disposal to prevent diabetes long-term complications such as cardiovascular disorders, kidney diseases, nephropathy, neuropathy, and retinopathy. Glycated albumin (GA) has recently gained more and more attention as a control biomarker thanks to its shorter lifespan and wider reliability compared to glycated hemoglobin (HbA1c), currently the “gold standard” for diabetes screening and monitoring in clinics. Various techniques such as ion exchange, liquid or affinity-based chromatography and immunoassay can be employed to accurately measure GA levels in serum samples; nevertheless, due to the cost of the lab equipment and complexity of the procedures, these methods are not commonly available at clinical sites and are not suitable to home monitoring. The present review describes the most up-to-date advances in the field of glycemic control biomarkers, exploring in particular the GA with a special focus on the recent experimental analysis techniques, using enzymatic and affinity methods. Finally, analysis steps and fundamental reading technologies are integrated into a processing pipeline, paving the way for future point-of-care testing (POCT). In this view, we highlight how this setup might be employed outside a laboratory environment to reduce the time from measurement to clinical decision, and to provide diabetic patients with a brand-new set of tools for glycemic self-monitoring.

Development of a hyperosmolar-hyperglycemic state and possible fulminant type 1 diabetes mellitus during the treatment of a case of adenocarcinoma of the lung and interstitial pneumonia

An 85-year-old man was being treated with anti-cancer drugs for adenocarcinoma of the lung and was on a tapering dose of prednisolone for interstitial pneumonia. He attended our hospital complaining of fatigue, thirst, and polyuria in September 2020. His postprandial plasma glucose concentration was 976 mg/dL, his glycated hemoglobin was 8.0%, his plasma osmolality was 342 mOsm/kg H2O, his urine ketone body content was 1 +, and his blood pH was 7.356. Therefore, we diagnosed a hyperosmolar-hyperglycemic state and he was admitted to the hospital for treatment. He had had no previous upper respiratory symptoms, and his postprandial plasma glucose and glycated hemoglobin were normal 13 days before he was first assessed (90 mg/dL and 5.9%, respectively). On admission, his serum pancreatic exocrine enzyme activities were high and he was negative for islet-specific autoantibodies. His serum C-peptide concentration was 0.60 ng/mL, suggesting that his endogenous insulin secretion was partially intact at that time. Although he did not meet the diagnostic criteria, we suspected him of having fulminant type 1 diabetes mellitus, because of the abrupt onset of hyperosmolar-hyperglycemic state. His general condition was improved by fluid and insulin administration. His human leukocyte antigen genotype was DRB1*04:05 DQB1*04:01:01, which is a disease susceptibility haplotype for fulminant type 1 diabetes mellitus. In addition, his prednisolone treatment may have caused an autoimmune abnormality, further predisposing toward the development of fulminant type 1 diabetes mellitus.

The fulminant index: A method of rapidly differentiating fulminant type 1 diabetes from diabetic ketoacidosis

AIMS AND OBJECTIVES

Fulminant type 1 diabetes (FT1D) could present diabetes ketoacidosis (DKA) at early onset. It is crucial to identify FT1D from DKA manifestations in time at clinical practice. This study was aimed at investigating whether the fulminant index (FI), encompassing plasma glucose (PG) to glycated haemoglobin (HbA1c) ratio (PG/HbA1c), serum potassium ion (K⁺ ) to HbA1c ratio (K⁺ /HbA1c) and serum sodium ion (Na⁺ ) multiplied by HbA1c (Na⁺ *HbA1c), is a feasible indicator for early FT1D diagnosis.

MATERIALS AND METHODS

A total of 78 subjects were enroled, including 40 FT1D patients and 38 non-FT1D patients with DKA. We utilised receiver operating characteristic (ROC) curve analysis to determine the FI cut-off values between FT1D and non-FT1D groups and examined efficacies of FI based on statistics.

RESULTS

ROC curve analyses showed that the maximum Youden's index for PG/HbA1c bonding to a cut-off value of 4.389, with the sensitivity of 75.0% and specificity of 81.6% in identifying FT1D from DKA. And optimal K⁺ /HbA1c cut-off value was 0.728 with a sensitivity of 90.0% and specificity of 84.2%. For Na⁺ *HbA1c, the best cut-off value was 923.65, and its sensitivity and specificity were 85% and 73.7%, respectively.

CONCLUSIONS

These results suggested FI could work as a valid and convenient indicator for differentiating FT1D from initial DKA patients. FI (K⁺ /HbA1c) presented the best efficacy as an independent index.

Diabetes mellitus in chronic kidney disease: Biomarkers beyond HbA1c to estimate glycemic control and diabetes-dependent morbidity and mortality

Diabetes mellitus (DM) is the leading cause of chronic kidney disease (CKD). Optimal glycemic control contributes to improved outcomes in patients with DM, particularly for microvascular damage, but blood glucose levels are too variable to provide an accurate assessment and instead markers averaging long-term glycemic load are used. The most established glycemic biomarker of long-term glycemic control is HbA1c. Nevertheless, HbA1c has pitfalls that limit its accuracy to estimate glycemic control, including the presence of altered red blood cell survival, hemoglobin glycation and suboptimal performance of HbA1c assays. Alternative methods to evaluate glycemic control in patients with DM include glycated albumin, fructosamine, 1-5 anhydroglucitol, continuous glucose measurement, self-monitoring of blood glucose and random blood glucose concentration measurements. Accordingly, our aim was to review the advantages and pitfalls of these methods in the context of CKD.

Serum 1,5-Anhydroglucitol to Glycated Albumin Ratio Can Help Early Distinguish Fulminant Type 1 Diabetes Mellitus from Newly Onset Type 1A Diabetes Mellitus

BACKGROUND

Fulminant type 1 diabetes mellitus (FT1DM) onsets abruptly and usually occurs within 1 week after the onset of hyperglycemic symptoms. Glycated albumin (GA) and 1,5-anhydroglucitol (1,5-AG) are indicators that reflect short-term glucose levels. This study was aimed at investigating whether the 1,5-AG/GA index (AGI) is a suitable indicator for early FT1DM identification.

METHODS

A total of 226 subjects were enrolled, all with glycated hemoglobin A1c (HbA1c) < 8.7%. FT1DM was diagnosed based on the 2012 Japan Diabetes Society criteria.

RESULTS

The AGI level was 0.54 (0.17-1.36) in the whole group. It was lower in FT1DM patients (0.16 [0.10-0.25]). Among the participants whose HbA1c did not exceed 7.0%, the AGI of FT1DM decreased significantly compared to type 1A diabetes (T1ADM) and latent autoimmune diabetes in adults (LADA) patients (0.16 [0.12-0.26] vs. 0.46 [0.24-0.72] vs. 0.46 [0.24-0.72] P < 0.05). The receiver operating characteristic (ROC) curve showed that AGI can be used to distinguish FT1DM and T1ADM patients with HbA1c < 8.7%. Diagnosing FT1DM based on AGI ≤ 0.3 only can help narrow down suspected FT1DM by up to 26.87%. If we diagnosed FT1DM when AGI was ≤0.3 and HbA1c was ≤7.0%, the success rate further increased to 86.57%, among which 85.00% of FT1DM and 87.23% of T1ADM patients were successfully identified. Therefore, using the combination criteria of AGI and HbA1c would improve the differential diagnosis efficacy by 61.11% compared with the AGI criterion only.

CONCLUSION

AGI can help facilitate the early differential diagnosis of FT1DM and T1ADM when HbA1c < 8.7%, with an optimal cut-off point of 0.3.

A Patient with Nivolumab-related Fulminant Type 1 Diabetes Mellitus whose Serum C-peptide Level Was Preserved at the Initial Detection of Hyperglycemia

A 77-year-old-man with renal cell carcinoma who was undergoing nivolumab treatment visited our department due to hyperglycemia; his plasma glucose level was 379 mg/dL. Although his serum C-peptide immunoreactivity (CPR) level was preserved (5.92 ng/mL), we suspected an onset of fulminant type 1 diabetes mellitus (FT1DM) and immediately started insulin therapy. His CPR levels gradually decreased and were depleted within 1 week. We later discovered that the patient's casual CPR level had been abnormally high (11.78 ng/mL) 2 weeks before his admission. Hence, the possibility of FT1DM in hyperglycemic patients undergoing nivolumab treatment should not be excluded, even with a preserved CPR level.

The clinical usefulness of glycated albumin in patients with diabetes and chronic kidney disease: Progress and challenges

Prolonged hyperglycemia leads to a non-enzymatic glycation of proteins, and produces Amadori products, such as glycated albumin (GA) and glycated hemoglobin (HbA1c). The utility of HbA1c in the setting of chronic kidney disease (CKD) may be problematic since altered lifespan of red blood cells, use of iron and/or erythropoietin therapy, uremia and so on. Therefore, as an alternative marker, GA has been suggested as a more reliable and sensitive glycemic index in patients with CKD. In addition to the mean plasma glucose concentration, GA also reflects postprandial plasma glucose and glycemic excursion. Besides, with a half-life of approximately 2-3 weeks, GA may reflect the status of blood glucose more rapidly than HbA1c. GA is also an early precursor of advanced glycation end products (AGEs), which cause alterations in various cellular proteins and organelles. Thus, high GA levels may correlate with adverse outcomes of patients with CKD. In this review, the clinical usefulness of GA was discussed, including a comparison of GA with HbA1c, the utility and limitations of GA as a glycemic index, its potential role in pathogenesis of diabetic nephropathy and the correlations between GA levels and outcomes, specifically in patients with diabetes and CKD.

Associations of body mass index with glycated albumin and glycated albumin/glycated hemoglobin A1c ratio in Chinese diabetic and non-diabetic populations

BACKGROUND

Recent studies have discussed the relationship between body mass index (BMI) and glycated albumin (GA) level. However, the extent of the influence of BMI on GA remains uncertain. We investigated the associations between BMI and GA, glycated hemoglobin A_1c (HbA_1c) and GA/HbA_1c, and to analyze the influence of obesity on GA, HbA_1c, and GA/HbA_1c in both Chinese diabetic and non-diabetic populations.

METHODS

A total of 2562 participants, including 1177 men and 1385 women (age 20-80 y), were enrolled. Each subject underwent a 75-g oral glucose tolerance test. Serum GA was detected using a liquid enzyme method, and HbA_1c was assayed using high-performance liquid chromatography.

RESULTS

In the diabetic patients (n = 1223), the GA, HbA_1c, and GA/HbA_1c levels were 16.7 ± 3.0%, 6.6 ± .9% (49 ± 9 mmol/mol), and 2.51 ± .33, respectively. In the non-diabetic subjects (n = 1339), the GA, HbA_1c, and GA/HbA_1c concentrations were 13.8 ± 1.7%, 5.6 ± .4% (38 ± 4 mmol/mol), and 2.47 ± .31, respectively. Decreasing trends in the GA and GA/HbA_1c concentrations and an increasing trend in the HbA_1c concentration (all P for trend <.05) were found to accompany with the increase in BMI, regardless of diabetes status. Multiple regression analysis revealed that BMI was independently related to HbA_1c in the non-diabetic population (standardized β = .158, P < .001); however, the relationship disappeared in the diabetic population (P > .05). Moreover, in the diabetic and non-diabetic populations, BMI was negatively correlated with GA (standardized β = -.167 and - .231, both P < .001) and GA/HbA_1c (standardized β = -.273 and - .310, both P < .001). Further analysis showed that a 1 kg/m² increment in BMI was associated with a .13% decrease in the absolute value of GA.

CONCLUSIONS

In both diabetic and non-diabetic populations, GA and GA/HbA_1c levels are independently and negatively associated with BMI. For every 1 kg/m² increment in BMI, the absolute value of GA decreases approximately .13%.

Glycated albumin: from biochemistry and laboratory medicine to clinical practice

This review summarizes current knowledge about glycated albumin. We review the changes induced by glycation on the properties of albumin, the pathological implications of high glycated albumin levels, glycated albumin quantification methods, and the use of glycated albumin as a complementary biomarker for diabetes mellitus diagnosis and monitoring and for dealing with long-term complications. The advantages and limits of this biomarker in different clinical settings are also discussed.

Glycated albumin is superior to glycated hemoglobin for glycemic control assessment at an early stage of diabetes treatment: A multicenter, prospective study

AIMS

This study was to determine whether serum glycated albumin (GA) was a better indicator of glycemic control than hemoglobin A1c (HbA1c) when starting a new treatment regimen for type 2 diabetes.

METHODS

Newly diagnosed type 2 diabetes patients, or patients who had poor glycemic control with oral hypoglycemic agents, were enrolled at 10 hospitals in Beijing. Serum GA, HbA1c, fasting blood glucose (FBG), and C-peptide were assayed on Days 0, 14, 28, and 91 after treatment.

RESULTS

Four hundred ninety-nine patients were enrolled. Mean FBG, GA and HbA1c decreased significantly in patients at Days 14, 28, and 91. In patients with improved glycemic control, the reduction of GA and HbA1c levels was 10.5±13.3% vs. 5.1±5.4% on Day 14, 16.0±13.4% vs. 9.0±7.0% on Day 28, and 18.0±16.7% vs. 18.3±9.4% on Day 91, respectively, compared with baseline values. Changes in GA on Day 14, 28 and 91 were all closely correlated with changes in HbA1c on Day 91. Change in GA on Day 14 was correlated with treatment effectiveness evaluated by HbA1c on Day 91.

CONCLUSIONS

GA may be a useful marker for assessing glycemic control at an early stage of new diabetes treatment and assist in guiding adjustments to treatment and therapy.

Is glycated albumin useful for differential diagnosis between fulminant type 1 diabetes mellitus and acute-onset autoimmune type 1 diabetes mellitus?

BACKGROUND

Markedly elevated plasma glucose and relatively low HbA1c compared to plasma glucose is one diagnostic criterion for fulminant type 1 diabetes mellitus (FT1DM). Glycated albumin (GA) is a glycemic control marker that reflects glycemic control in shorter period than HbA1c. This study investigated whether GA is useful for differential diagnosis between FT1DM and acute-onset autoimmune type 1 diabetes mellitus (T1ADM) or not.

METHODS

This study included 38 FT1DM patients and 31 T1ADM patients in whom both HbA1c and GA were measured at the time of diagnosis.

RESULTS

In FT1DM patients, as compared to T1ADM patients, both HbA1c and GA were significantly lower (HbA1c; 6.6±0.9% vs. 11.7±2.6%, P<0.0001, GA; 22.9±4.8% vs. 44.3±8.3%, P<0.0001). For differential diagnosis between FT1DM and T1ADM, ROC analysis showed that the optimum cut-off value for GA was 33.5% with sensitivity and specificity of 97.4% and 96.8%, respectively, while the optimum cut-off value for HbA1c was 8.7% with sensitivity and specificity of 100% and 83.9%, respectively.

CONCLUSIONS

GA also may be useful for the differential diagnosis between FT1DM and T1ADM when the cut-off value can be set at 33.5%.

Glycated Serum Albumin and AGE Receptors

In vivo modification of proteins by molecules with reactive carbonyl groups leads to intermediate and advanced glycation end products (AGE). Glucose is a significant glycation reagent due to its high physiological concentration and poorly controlled diabetics show increased albumin glycation. Increased levels of glycated and AGE-modified albumin have been linked to diabetic complications, neurodegeneration, and vascular disease. This review discusses glycated albumin formation, structural consequences of albumin glycation on drug binding, removal of circulating AGE by several scavenger receptors, as well as AGE-induced proinflammatory signaling through activation of the receptor for AGE. Analytical methods for quantitative detection of protein glycation and AGE formation are compared. Finally, the use of glycated albumin as a novel clinical marker to monitor glycemic control is discussed and compared to glycated hemoglobin (HbA1c) as long-term indicator of glycemic status.

1,5-Anhydroglucitol and glycated albumin in glycemia

The main purpose of treating diabetes is to prevent the onset and the progression of diabetic chronic complications. Since the mechanism of onset of chronic complications is still not well understood, the main strategy to achieve this purpose is to bring the plasma glucose level in diabetic patients as close as possible to that in healthy subjects and try to maintain good glycemic control over the long term. Glycated hemoglobin (HbA1c), glycated albumin (GA), fructosamine, and 1,5-anhydroglucitol (1,5 AG) are used for evaluating glycemic control. At present, HbA1c is widely used as a gold standard index for glycemic control in clinical practice. While HbA1c reflects the long-term glycemic control state (for the past 1-2 months), it does not accurately reflect glycemic control in the clinical state in which glycemic control improves or deteriorates in the short-term. It is also known that HbA1c in patients with hematological disorders such as anemia and variant hemoglobin shows an abnormal value. In addition, HbA1c mainly reflects the mean plasma glucose but does not reflect the postprandial plasma glucose. On the other hand, GA and 1,5-AG reflect intermediate- or short-term glycemic control and are not influenced by hemoglobin metabolism. While 1,5-AG is known to reflect the postprandial plasma glucose, it was shown recently that GA also reflects the postprandial plasma glucose. This chapter summarizes the measurement methods, usage methods, evidence, and problems concerning such indices for glycemic control.

The ratio of estimated average glucose to fasting plasma glucose level is superior to glycated albumin, hemoglobin A1c, fructosamine, and GA/A1c ratio for assessing β-cell function in childhood diabetes

Objective. This study investigated the use of the estimated average glucose to fasting plasma glucose ratio (eAG/fPG ratio) to screen for β-cell function in pediatric diabetes. Methods. Glycated hemoglobin (HbA1c), glycated albumin (GA), fructosamine, insulin, and C-peptide levels were measured. The ratio of GA to HbA1c (GA/A1c ratio) was calculated, and the homeostasis model assessment of β-cell function (HOMA-β) was determined. Results. Median values of C-peptide, insulin, and HOMA-β levels were significantly higher in patients with an increased eAG/fPG ratio than in those with a decreased eAG/fPG ratio. C-peptide and HOMA-β levels were more closely correlated with the eAG/fPG ratio than with GA, HbA1c, the GA/A1c ratio, and fructosamine. In contrast, body mass index was significantly associated with GA, GA/A1c ratio, and fructosamine, but not with the eAG/fPG ratio and HbA1c levels. To test the diagnostic accuracies of the eAG/fPG ratio for identifying HOMA-β > 30.0% in patients with type 2 diabetes, the area under the ROC curve of the eAG/fPG ratio was significantly larger than that of the GA/A1c ratio [0.877 (95% CI, 0.780–0.942) versus 0.775 (95% CI, 0.664–0.865), P = 0.039]. Conclusions. A measurement of the eAG/fPG ratio may provide helpful information for assessing β-cell function in pediatric patients with diabetes.

Correlation of glycated albumin but not hemoglobin A1c with endogenous insulin secretion in fulminant type 1 diabetes mellitus

Aims/Introduction:  Fulminant type 1 diabetes mellitus (FT1DM) develops as a result of very rapid and almost complete pancreatic β‐cell destruction. We hypothesized that in patients with FT1DM who have less endogenous insulin secretion, disease progression is more rapid, and thus glycated albumin (GA) levels are lower. This study was designed to prove this hypothesis.

Materials and Methods:  The present study included 42 patients with FT1DM (24 men, 18 women) in whom glycated hemoglobin (HbA_1c), GA and daily urinary C‐peptide (CPR) were measured at the time of diagnosis. Patients with complications, such as liver disease, kidney disease, anemia, or who were pregnant were excluded.

Results:  Urinary CPR (log transformed) was not correlated with HbA_1c (R = 0.168, P = 0.287), but was positively correlated with GA (R = 0.336, P = 0.030). It was weakly, but not significantly, correlated with GA/HbA_1c ratio (R = 0.281, P = 0.072). In patients with GA < 24.0%, urinary CPR was significantly lower than in patients with GA ≥ 24.0%. In addition, in patients with GA/HbA_1c ratio <3.8, urinary CPR was significantly lower than in patients with GA/HbA_1c ratio ≥ 3.8.

Conclusions:  Our findings suggest that in patients with FT1DM, GA at the time of diagnosis was correlated with endogenous insulin secretion. GA < 24.0% at the time of diagnosis is predictive for less endogenous insulin secretion in patients with FT1DM. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2010.00050.x, 2010)

Glycemic control indicators in patients with neonatal diabetes mellitus

Neonatal diabetes mellitus (NDM) is a type of diabetes mellitus caused by genetic abnormality which develops in insulin dependent state within 6 mo after birth. HbA1c is widely used in clinical practice for diabetes mellitus as the gold standard glycemic control indicator; however, fetal hemoglobin (HbF) is the main hemoglobin in neonates and so HbA1c cannot be used as a glycemic control indicator in NDM. Glycated albumin (GA), another glycemic control indicator, is not affected by HbF. We reported that GA can be used as a glycemic control indicator in NDM. However, it was later found that because of increased metabolism of albumin, GA shows an apparently lower level in relation to plasma glucose in NDM; measures to solve this problem were needed. In this review, we outlined the most recent findings concerning glycemic control indicators in neonates or NDM.

Glycated albumin; clinical usefulness

The main purpose of treating diabetes is to prevent the onset and progression of diabetic chronic complications. Since the mechanism of onset of chronic complications is still not well understood, the main strategy to achieve this purpose is to bring plasma glucose levels as close as possible to those in healthy subjects and maintain good glycemic control over the long term. Since glycation among various proteins is increased in diabetic patients compared with non-diabetic subjects, glycated protein can be used as a glycemic control indicator. Currently, among these glycated proteins, HbA1c is used as the gold standard of glycemic control indicators. However, HbA1c does not accurately reflect the actual status of glycemic control in some conditions with rapid changes in glycemic control and in patients with anemia (hemolytic anemia, iron deficiency anemia, etc.) and variant hemoglobin. In comparison, glycated albumin (GA) more accurately reflects changes in plasma glucose during the short term and postprandial plasma glucose. GA also reflects glycemic control in patients with hematologic disorders whereas GA does not reflect glycemic control in patients with disorder of albumin metabolism. GA is a glycemic control indicator which overcomes most of the disadvantages of HbA1c, and could be therefore expected to replace HbA1c as the standard glycemic control indicator in the near future. However, it is necessary to accumulate more evidences from large research studies on the effective directions for measuring GA.

Metformin decreases glycated albumin to glycated haemoglobin ratio in patients with newly diagnosed type 2 diabetes

Background

To know whether metformin improves postprandial hyperglycaemia, we examined the effect of metformin on the glycated albumin (GA) to glycated haemoglobin (HbA1c) ratio (GA/HbA1c ratio) in patients with newly diagnosed type 2 diabetes.

Methods

Metformin and lifestyle interventions were initiated in 18 patients with newly diagnosed type 2 diabetes. Metformin was titrated to 1500 mg/day or maximum-tolerated dose. HbA1c and GA were measured every four weeks up to 24 weeks.

Results

HbA1c decreased significantly from 9.0 ± 2.1% at baseline to 6.5 ± 0.9% at week 24, and GA decreased significantly from 24.3 ± 8.2% to 16.2 ± 3.1%. The GA/HbA1c ratio decreased significantly from 2.66 ± 0.37 at baseline to 2.47 ± 0.29 at week 24 ( P < 0.01), despite that the GA/HbA1c ratio reached a plateau value at week 16. The change in the GA/HbA1c ratio during 24 weeks (ΔGA/HbA1c ratio) was significantly correlated with both baseline HbA1c and GA. Moreover, the ΔGA/HbA1c ratio was significantly correlated with the change in GA during 24 weeks but not with the change in HbA1c.

Conclusions

Metformin decreased the GA/HbA1c ratio in patients with newly diagnosed type 2 diabetes. This suggests that metformin improves postprandial hyperglycaemia in patients with newly diagnosed type 2 diabetes.

Study of a newly developed high-performance liquid chromatography analyser for glycosylated haemoglobin measurements in blood containing haemoglobin variants in the Japanese population

Background

This study examined the new high-performance liquid chromatography analyser HLC-723GX (GX) and investigated its ability to both measure glycosylated haemoglobin (HbA1c) values and determine whether haemoglobin variants could cause interference with these measurements in the Japanese population.

Methods

For the basic GX examination, the within- and between-run precision, linearity of measurements, correlation of HbA1c values with current systems and the interference of chemically modified haemoglobin were determined. GX interference caused by the haemoglobin variant was examined by analysing 39 clinical laboratory samples that contained haemoglobin variants.

Results

Good within- and between-run precision were found, with the coefficients of variation at ≤1.0%. A wide range of HbA1c measurement values were confirmed, with the HbA1c values strongly correlated with the results of the currently used HLC-723G8 system. Chemically modified haemoglobins were prepared by adding glucose, sodium cyanate, acetaldehyde or acetylsalicylic acid to normal blood samples. None of these samples had any influence on the HbA1c values determined by GX. GX analysis showed haemoglobin variants that eluted after HbA0 and were similar to HbD, or HbS had HbA1c values that were close to those measured by boronate affinity chromatography and immunoassay. GX found lower HbA1c values in blood that contained HbE or haemoglobin variants, which elute before or at nearly the same time as HbA0.

Conclusions

GX is useful for the analysis of HbA1c samples that contain HbD, HbS, HbC and haemoglobin variants, even though the elution times are similar. However, a countermeasure is needed in order to avoid overlooking other haemoglobin variants in Japan.

Serum glycated albumin as a new glycemic marker in pediatric diabetes

PURPOSE

Serum glycated albumin (GA) has been recently used as another glycemic marker that reflects shorter term glycemic control than glycated hemoglobin (HbA1c). Insulin secretory function and glycemic fluctuation might be correlated with the ratio of GA to HbA1c (GA/HbA1c) in diabetic adult patients. This study investigated the association of GA and GA/HbA1c ratio with the levels of fasting C-peptide, fasting plasma glucose in type 1 and type 2 pediatric diabetes.

METHODS

Total 50 cases from 42 patients were included. The subjects were classified into type 1 diabetes mellitus (T1DM) (n=30) and type 2 diabetes mellitus (T2DM) (n=20) group. The associations among HbA1c, GA, and GA/HbA1c ratio were examined. The relationship between the three glycemic indices and fasting glucose, fasting C-peptide were analyzed.

RESULTS

Mean values of GA, the GA/HbA1c ratio were significantly higher in T1DM than T2DM. GA (r=0.532, P=0.001), HbA1c (r=0.519, P=0.002) and the GA/HbA1c ratio (r=0.409, P=0.016) were correlated with the fasting plasma glucose. Fasting C-peptide level arranged 4.22±3.22 ng/mL in T2DM, which was significantly above the values in T1DM (0.26±0.49 ng/mL). There were no significant correlation between HbA1c and fasting C-peptide level. However, GA and the GA/HbA1c ratio exhibited inverse correlations with fasting C-peptide level (r=-0.214, P=0.002; r=-0.516, P<0.001).

CONCLUSION

GA seems to more accurately reflects fasting plasma glucose level than HbA1c. GA, GA/HbA1c ratio appear to reflect insulin secretory function.

Report of the Committee of the Japan Diabetes Society on the Research of Fulminant and Acute-onset Type 1 Diabetes Mellitus: New diagnostic criteria of fulminant type 1 diabetes mellitus (2012)

We have revised a part of the diagnostic criteria for fulminant type 1 diabetes. The new criteria were set both to express the essence of this disease of rapid increase of patients' blood glucose and to be highly sensitive to reduce the misdiagnosis. After analyzing the data of 382 patients with newly-diagnosed fulminant type 1 diabetes, we adopted the glycated hemoglobin (HbA1c) level of 8.7% (National Glycohemoglobin Standardization Program [NGSP] value). The new criterion indicates 100% of sensitivity and the best value by receiver operating characteristic curve analysis. In addition, we added a comment that 'This value (HbA1c <8.7% in NGSP) is not applicable for patients with previously diagnosed glucose intolerance' in the new criteria and also a comment that 'Association with human leukocyte antigen DRB1*04:05-DQB1*04:01 is reported' as a related finding. We did not revise the screening criteria and the other part of the diagnostic criteria, because they are still reliable.

New indices for predicting glycaemic variability

Blood glucose variability is known to be associated with increased risk of long-term complications. Reliable indices for predicting hyperglycaemic and hypoglycaemic fluctuations are therefore needed. Glycaemic standard deviation (SD) obtained by continuous glucose monitoring correlates closely with nine previously described glycaemic variability formulas. Here, new indices predictive of glycaemic variability were developed, which can be calculated from laboratory measures based on a single blood draw. The indices included the glycated albumin (GA) to HbA1c ratio (GA/A1c ratio) and the fasting C-peptide immunoreactivity (FCPR) to fasting plasma glucose (FPG) ratio (FCPR index). Predictive values of these indices were assessed in 100 adults with diabetes. GA/A1c ratio and FCPR index showed close associations with glycaemic SD in addition to the nine existing glucose variability formulas. Subjects with a GA/A1c ratio ≥ 2.8 and FCPR index <3.0 showed the greatest SD and longest durations of hypoglycaemia, while those with a GA/A1c ratio <2.8 and FCPR index ≥ 3.0 had smaller SDs and little sign of hypoglycaemia. In adults with diabetes, a high GA/A1c ratio and low FCPR index value reflect higher glycaemic excursions, irrespective of diabetes type. Simultaneous measurements of GA, HbA1c, FPG and FCPR may help to identify a group of patients who warrant closer monitoring in relation to glycaemic variability and hypoglycaemia.

Estimation of Duration of Symptoms in Fulminant Type 1 Diabetes Mellitus Using HbA1c or Glycated Albumin

Fulminant type 1 diabetes mellitus (FT1DM) develops as a result of very rapid and almost complete destruction of pancreatic β cells. Because of an abrupt increase in plasma glucose, HbA_1c and glycated albumin (GA) might increase along with duration of symptoms in FT1DM patients. We attempted to devise a formula to estimate duration of symptoms based on the increased levels in HbA_1c or GA. Four patients who developed FT1DM during the course of type 2 diabetes mellitus and in whom HbA_1c was measured before onset were investigated in this study. The percents of the estimated duration of symptoms calculated from HbA_1c (four patients) and GA (two patients) to the actual duration were 137 ± 88% and 122%, respectively. In FT1DM patients in whom HbA_1c and/or GA before onset and at the time of ketoacidosis are measured, duration of symptoms might be estimated with using the increased levels in HbA_1c or GA.

Glycated albumin levels are higher relative to HbA1c levels in people with autoimmune acute-onset type 1 diabetes mellitus than in people with type 2 diabetes mellitus at the time of diagnosis

Glycated albumin (GA) is a new glycemic control indicator. GA/HbA1c ratio in autoimmune acute-onset type 1 diabetes mellitus patients was significantly higher than in type 2 diabetes mellitus patients at the time of diagnosis. This difference might reflect speed of increase in plasma glucose after the onset of diabetes.

Glycated albumin but not HbA1c reflects glycaemic control in patients with neonatal diabetes mellitus

AIMS/HYPOTHESIS

It is difficult to use HbA(1c) as an indicator of glycaemic control in patients with neonatal diabetes mellitus (NDM) because of high levels of fetal haemoglobin (HbF) remaining in the blood. In this study, glycated albumin (GA), which is not affected by HbF, and HbA(1c) were compared to evaluate whether they reflect glycaemic control in patients with NDM.

METHODS

This study included five patients with NDM. Age at diagnosis was 38 ± 20 days. Insulin therapy was started in all patients, and levels of GA, HbA(1c) and HbF were measured monthly for 6 months. One-month average preprandial plasma glucose (aPPG) was calculated using self-monitoring of blood glucose.

RESULTS

Plasma glucose and GA were elevated (29.7 ± 13.1 mmol/l [n = 5] and 33.3 ± 6.9% [n = 3], respectively) but HbA(1c) was within normal limits (5.4 ± 2.6% [35.5 ± 4.9 mmol/mol]; n = 4) at diagnosis. With diabetes treatment, aPPG (r = -0.565, p = 0.002), GA (r = -0.552, p = 0.003) and HbF (r = -0.855, p < 0.0001) decreased with age, whereas HbA(1c) increased (r = 0.449, p = 0.004). GA was strongly positively correlated with aPPG (r = 0.784, p < 0.0001), while HbA(1c) showed no correlation with aPPG (r = 0.221, p = 0.257) and was significantly inversely correlated with HbF (r = -0.539, p = 0.004).

CONCLUSIONS/INTERPRETATION

GA is a useful indicator of glycaemic control in patients with NDM, whereas HbA(1c) is influenced by age-related changes in HbF and does not accurately reflect glycaemic control.

Clinical impact of glycated albumin as another glycemic control marker

It is known that glycation among various proteins is increased in diabetic patients compared with non-diabetic subjects. Currently, among these glycated proteins, glycated hemoglobin (HbA(1C)) is used as the gold standard index of glycemic control in clinical practice for diabetes treatment. However, HbA(1C) does not accurately reflect the actual status of glycemic control in some conditions where plasma glucose changes during short term, and in patients who have diseases such as anemia and variant hemoglobin. In comparison, another index of glycemic control, glycated albumin (GA), more accurately reflects changes in plasma glucose during short term and also postprandial plasma glucose. Although GA is not influenced by disorders of hemoglobin metabolism, it is affected by disorders of albumin metabolism. This review summarizes diseases and pathological conditions where GA measurement is useful. These include the status of glycemic control changes during short term, diseases which cause postprandial hyperglycemia, iron deficiency anemia, pregnancy, chronic liver disease (liver cirrhosis), chronic renal failure (diabetic nephropathy), and variant hemoglobin.