Relationship between clinical markers of glycemia and glucose excursion evaluated by continuous glucose monitoring (CGM)

Glycated albumin may have a complementary role to glycated hemoglobin in glucose monitoring in childhood acute leukemia

PURPOSE

Glycated hemoglobin (HbA1c) as a glycemic index may have limited value in pediatric patients with acute leukemia as they often present with anemia and/or pancytopenia. To address this issue, we evaluated the usefulness of glycated albumin (GA) as a glycemic monitoring index in pediatric patients with acute leukemia.

METHODS

Medical records of 25 patients with type 2 diabetes mellitus (T2DM), 63 patients with acute leukemia, and 115 healthy children from Seoul St. Mary's Hospital, The Catholic University of Korea, were retrospectively investigated for serum GA, HbA1c, and fasting blood glucose (FBG) levels, along with demographic data.

RESULTS

GA, HbA1c, and FBG levels did not differ between the control and acute leukemia groups. In the T2DM group, positive correlations were observed among GA, HbA1c, and FBG (P<0.01). Although GA level was not associated with the HbA1c level in the control group, GA and HbA1c levels showed a positive correlation in the acute leukemia group (P=0.045). Regression analysis revealed GA and HbA1c levels to be positively correlated in the acute leukemia and T2DM groups even after adjusting for age, sex, and body mass index z-score (P=0.007, P<0.01).

CONCLUSION

GA may be a useful complementary parameter to HbA1c for glycemic monitoring in pediatric patients with acute leukemia, similar to its use in patients with T2DM.

Association of the Ratio of Glycoalbumin to Hemoglobin A1c With Season Change and the COVID-19 Pandemic in Patients With Type 2 Diabetes Mellitus

AIM

The main purpose of the current study was to investigate the effect of season change and the influence of the COVID-19 pandemic on the ratio of glycoalbumin to hemoglobin A1c (GA/HbA1c) in patients with type 2 diabetes.

PATIENTS AND METHODS

A total of 267 patients in whom both HbA1c and GA were measured at baseline were included in this retrospective study. GA/HbA1c was investigated for three years, 2018, 2019, and 2020 (COVID-19 pandemic period).

RESULTS

The mean values for GA/HbA1c per year in 2018, 2019, and 2020 were 2.64±0.35, 2.61±0.35, 2.64±0.39, respectively. There were no significant differences in GA/HbA1c during these years. There was a tendency toward seasonal variation in GA/HbA1c (i.e., higher in summer or autumn and lower in spring or winter).

CONCLUSION

In patients with type 2 diabetes, GA/HbA1c tended to show seasonal variation, which was not influenced by the COVID-19 pandemic.

Pre-stroke glycemic variability estimated by glycated albumin predicts hematoma expansion and poor outcomes in patients with spontaneous intracerebral hemorrhage

Glycemic variability has been shown to be correlated more with oxidative stress than chronic hyperglycemia. We evaluated the impact of pre-stroke glycemic variability measured using glycated albumin (GA) on hematoma expansion and clinical outcomes following spontaneous intracerebral hemorrhage (ICH). We consecutively enrolled 343 patients with ICH for 72 months using a single-center registry database. The primary outcome measure was hematoma expansion. The secondary outcome measures were early neurological deterioration (END), 1-month mortality, and 3-month poor functional outcomes (modified Rankin scale score of 4-6). The patients were divided into two groups based on pre-stroke glycemic variability: a higher GA group (GA ≥ 16.0%) and a lower GA group (GA < 16.0%). During the study period, there were 63 (18.4%) events of hematoma expansion, 61 (17.8%) of END, 45 (13.1%) of 1-month mortality, and 45 (13.1%) of 3-month poor functional outcomes after ICH. The higher GA group (36.4%) had higher rates of hematoma expansion, END, 1-month mortality, and 3-month poor functional outcomes than the lower GA group. Multivariate analysis showed that a higher GA level was significantly associated with increased hematoma expansion (adjusted odds ratio 5.83; 95% confidence interval [CI] 2.58-13.19, p < 0.001). The area under the receiver operating characteristic curve of GA (0.83; 95% CI 0.48-0.65) for predicting hematoma expansion was higher than that of glycated hemoglobin (0.57; 95% CI 0.48-0.65, p for DeLong's pairwise comparison < 0.001). Higher GA levels could be a reliable marker for predicting hematoma expansion and poor outcomes following ICH.

Prepregnancy body mass index and glycated albumin in the third trimester may predict infant complications in gestational diabetes mellitus: a retrospective cohort study

Background

Maternal hyperglycemia, obesity, and hypertension with gestational diabetes mellitus (GDM) are risk factors for infant complications. This study aimed to investigate maternal factors and glycemic control indicators that affect infant complications in GDM.

Methods

We conducted a retrospective cohort study including 112 mothers with GDM and their infants. Multivariate logistic regression analysis was used to investigate the variables associated with good and adverse infant outcomes. We determined the cutoff values of variables that showed a significant difference in the multivariate logistic regression analysis for predicting infant complications by performing receiver operating characteristic curve analysis.

Results

In the multivariate logistic regression analysis, prepregnancy BMI and GA in the third trimester were significantly related to good and adverse infant outcomes (adjusted odds ratios [aORs], 1.62; 95% CIs 1.17-2.25, p = 0.003 and aORs, 2.77; 95% CIs 1.15-6.64, p = 0.022, respectively). The cutoff values for prepregnancy BMI and GA in the third trimester were 25.3 kg/m2 and 13.5%, respectively.

Conclusions

The importance of weight control before pregnancy and the usefulness of GA in the third trimester to predict infant complications were suggested in this study.

Correlation Between Time in Range and HbA1c in People with Type 2 Diabetes on Basal Insulin: Post Hoc Analysis of the SWITCH PRO Study

INTRODUCTION

Use of continuous glucose monitoring (CGM) in people with diabetes may provide a more complete picture of glycemic control than glycated hemoglobin (HbA1c) measurements, which do not capture day-to-day fluctuations in blood glucose levels. The randomized, crossover, phase IV SWITCH PRO study assessed time in range (TIR), derived from CGM, following treatment with insulin degludec or insulin glargine U100 in patients with type 2 diabetes at risk for hypoglycemia. This post hoc analysis evaluated the relationship between TIR and HbA1c, following treatment intensification during the SWITCH PRO study.

METHODS

Correlation between absolute values for TIR (assessed over 2-week intervals) and HbA1c, at baseline and at the end of maintenance period 1 (M1; week 18) or maintenance period 2 (M2; week 36), were assessed by linear regression and using the Spearman correlation coefficient (r_s). These methods were also used to assess correlation between change in TIR and change in HbA1c from baseline to the end of M1, both in the full cohort and in subgroups stratified by baseline median HbA1c (≥ 7.5% [≥ 58.5 mmol/mol] or < 7.5% [< 58.5 mmol/mol]).

RESULTS

A total of 419 participants were included in the analysis. A moderate inverse linear correlation was observed between TIR and HbA1c at baseline (r_s -0.54), becoming stronger following treatment intensification during maintenance periods M1 (weeks 17-18: r_s -0.59) and M2 (weeks 35-36: r_s -0.60). Changes in TIR and HbA1c from baseline to end of M1 were also linearly inversely correlated in the full cohort (r_s -0.40) and the subgroup with baseline HbA1c ≥ 7.5% (r_s -0.43). This was less apparent in the subgroup with baseline HbA1c < 7.5% (r_s -0.17) (p-interaction = 0.07).

CONCLUSION

Results from this post hoc analysis of data from SWITCH PRO, one of the first large interventional clinical studies to use TIR as the primary outcome, further support TIR as a valid clinical indicator of glycemic control.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT03687827.

Serum glycated albumin is associated with in-stent restenosis in patients with acute coronary syndrome after percutaneous coronary intervention with drug-eluting stents: An observational study

Background

Previous studies have confirmed the predicted value of serum glycated albumin (GA) in atherosclerotic cardiovascular disease. However, the relationship between GA and the development of in-stent restenosis (ISR) after drug-eluting stent (DES) implantation has not been verified in patients with acute coronary syndrome (ACS).

Materials and methods

In this study, 797 patients diagnosed with ACS who underwent re-coronary angiography more than 6 months after the first successful DES-based percutaneous coronary intervention (PCI) were eventually included. Patients were categorized into two groups based on the median GA levels of 14.94%. Moreover, multivariate logistic regression analysis models and the net reclassification improvement and integrated differentiation improvement risk models were constructed to assess the relationship between the GA and DES-ISR in patients with ACS.

Results

The GA was significantly associated with an increased risk of DES-ISR, upon adjusting for confounding factors (as nominal variate: OR 1.868, 95% CI 1.191-2.932, P = 0.007; as continuous variate: OR 1.109, 95% CI 1.040-1.183, P = 0.002). The addition of GA to a baseline risk model had an incremental effect on the predictive value for DES-ISR (AUC: GA vs. baseline model, 0.714 vs. 0.692, comparison P = 0.017; category-free net reclassification improvement (NRI) 0.080, P = 0.035; integrated discrimination improvement (IDI) 0.023, P < 0.001).

Conclusion

GA level was significantly associated with a high risk of DES-ISR in patients with ACS treated with PCI. Moreover, the addition of the GA to a baseline risk model has an incremental effect on the predictive potential for DES-ISR.

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.

Discordance in the reduction rate between glycated albumin and glycated hemoglobin levels in type 2 diabetes patients receiving SGLT2 inhibitors

AIMS

Although the difference in HbA_1c reduction between sodium-glucose cotransporter 2 (SGLT2) inhibitors and other oral glucose-lowering agents is relatively small, SGLT2 inhibitors exhibit beneficial cardiorenal protection. This study was based on the hypothesis that changes of HbA_1c in patients treated with SGLT2 inhibitors may not accurately reflect an improved glycemic profile.

METHODS

Two studies were conducted: 1) a retrospective cohort study of 3039 patients administered with either an SGLT2 or a dipeptidyl peptidase-4 (DPP4) inhibitor for 12 months comparing the changes in glycated albumin (GA) and HbA_1c levels and 2) a pilot study of 10 patients whose glycemic dynamics were evaluated using flash glucose monitoring at baseline and 2 months after treatment with an SGLT2 inhibitor.

RESULTS

SGLT2 inhibitors reduced GA more markedly than HbA_1c in both studies. DPP4 inhibitors decreased both GA and HbA_1c to a comparable degree. The mean glucose levels and glycemic standard deviation were significantly reduced after treatment with an SGLT2 inhibitor, in concordance with GA decline, although the lowering of HbA_1c was marginal.

CONCLUSIONS

Changes in HbA_1c levels underestimated the glucose-lowering effect and the diminished glycemic fluctuation induced by SGLT2 inhibitors. Thus, the distinct biomarker roles of GA and HbA_1c should be reevaluated.

Clinical usefulness of glycated albumin and glycated albumin-to-glycated hemoglobin ratio of gestational diabetes mellitus in late pregnancy for predicting infant complications

BACKGROUND

Gestational diabetes mellitus (GDM) with poorly controlled glycemia is associated with poor pregnancy outcomes. However, adequate markers for glycemic control in GDM have not been fully evaluated.

METHODS

We retrospectively studied 77 patients with GDM and their infants. Mean glycated albumin (GA), glycated hemoglobin (HbA1c), and GA/HbA1c in GDM were compared between two groups stratified by the presence or absence of infant complications (complications or non-complications). We assessed the predictability of infant complications in GA, HbA1c, and GA/HbA1c of women with GDM by receiver operating characteristic analysis (ROC).

RESULTS

In complications and non-complications, GA and GA/HbA1c were significantly associated with neonatal hypoglycemia (13.9% vs. 13.0%, p < 0.001 and 2.49 vs. 2.33, p < 0.001, respectively), respiratory disorders (13.7% vs. 13.2%, p = 0.013 and 2.48 vs. 2.34, p < 0.001, respectively), myocardial hypertrophy (14.5% vs. 13.0%, p < 0.001 and 2.59 vs. 2.33, p < 0.001, respectively), and large for gestational age (14.5% vs. 13.1%, p < 0.001 and 2.58 vs. 2.34, p < 0.001, respectively). Compared with each infant complication in ROC, GA and GA/HbA1c had higher area under the curve than HbA1c. Especially, GA and GA/HbA1c had highest AUC in predicting myocardial hypertrophy and large for gestational age (GA; 0.92 and 0.92, GA/HbA1c; 0.91 and 0.86, respectively). Although statistically significant positive correlations were found between GA and GA/HbA1c and the number of infant complications (GA: r = 0.417, p < 0.001; GA/HbA1c: r = 0.408, p < 0.001), their correlations were weak.

CONCLUSION

Compared with HbA1c, GA and GA/HbA1c of GDM in late pregnancy might be useful for predicting infant complications arising from GDM.

Prognostic implication of serum glycated albumin for patients with non-ST-segment elevation acute coronary syndrome undergoing percutaneous coronary intervention

BACKGROUND

It has been demonstrated that glycated albumin (GA) is significantly associated with diabetes complications and mortality. However, among patients diagnosed with non-ST-elevation acute coronary syndrome (NSTE-ACS) administered percutaneous coronary intervention (PCI), the predictive value of GA for poor prognosis is unclear.

METHODS

This study eventually included 2247 NSTE-ACS patients in Beijing Anzhen Hospital, Capital Medical University in January-December 2015 who received PCI. All patients were followed up until death or for 48 months post-discharge. The primary endpoint was major adverse cardio-cerebral events (MACCEs), including all-cause death, non-fatal myocardial infarction, ischemia-induced revascularization and non-fatal ischemic stroke.

RESULTS

In total, 547 (24.3%) MACCEs were recorded during the follow-up period. Upon adjusting for potential confounders, GA remained an important risk predictor of MACCEs (As nominal variate: hazard ratio [HR] 1.527, 95% confidence interval [CI] 1.236-1.886, P < 0.001; As continuous variate: HR 1.053, 95% CI 1.027-1.079, P < 0.001). GA addition significantly enhanced the predictive ability of the traditional risk model (Harrell's C-index, GA vs. Baseline model, 0.694 vs. 0.684, comparison P = 0.002; continuous net reclassification improvement (continuous-NRI) 0.085, P = 0.053; integrated discrimination improvement (IDI) 0.007, P = 0.020).

CONCLUSION

GA is highly correlated with poor prognosis in NSTE-ACS patients undergoing PCI, suggesting that it may be a major predictive factor of adverse events among these individuals.

Effect of insulin degludec versus insulin glargine U100 on time in range: SWITCH PRO, a crossover study of basal insulin-treated adults with type 2 diabetes and risk factors for hypoglycaemia

AIMS

To compare time in range (TIR) with use of insulin degludec U100 (degludec) versus insulin glargine U100 (glargine U100) in people with type 2 diabetes.

MATERIALS AND METHODS

We conducted a randomized, crossover, multicentre trial comparing degludec and glargine U100 in basal insulin-treated adults with type 2 diabetes and ≥1 hypoglycaemia risk factor. There were two treatment periods, each with 16-week titration and 2-week maintenance phases (with evaluation of glucose using blinded professional continuous glucose monitoring). The once-weekly titration (target: 3.9-5.0 mmol/L) was based on pre-breakfast self-measured blood glucose. The primary endpoint was percentage of TIR (3.9─10.0 mmol/L). Secondary endpoints included overall and nocturnal percentage of time in tight glycaemic range (3.9-7.8 mmol/L), and mean glycated haemoglobin (HbA1c) and glucose levels.

RESULTS

At baseline, participants (n = 498) had a mean (SD) age of 62.8 (9.8) years, a diabetes duration of 15.1 (7.7) years and an HbA1c level of 59.6 (11.0) mmol/mol (7.6 [1.0]%). Noninferiority and superiority were confirmed for degludec versus glargine U100 for the primary endpoint, with a mean TIR of 72.1% for degludec versus 70.7% for glargine U100 (estimated treatment difference [ETD] 1.43% [95% confidence interval (CI): 0.12, 2.74; P = 0.03] or 20.6 min/d). Overall time in tight glycaemic range favoured degludec versus glargine U100 (ETD 1.5% [95% CI: 0.15, 2.89] or 21.9 min/d). Degludec also reduced nocturnal time below range (TBR; <3.9 mmol/L) compared with glargine U100 (ETD -0.88% [95% CI: -1.34, -0.42] or 12.7 min/night; post hoc) and significantly fewer nocturnal hypoglycaemic episodes of <3.0 mmol/L were observed.

CONCLUSIONS

Degludec, compared with glargine U100, provided more TIR and time in tight glycaemic range, and reduced nocturnal TBR in insulin-treated people with type 2 diabetes.

Glycated albumin as biomarker: Evidence and its outcomes

Glycemic control markers are important for the diagnosis and treatment of diabetes. Hemoglobin A1c (A1C) is an important marker that is mandatory in routine medical examinations; however, it is well known that it has some limitations. In this review, we focus on the limitation of A1C and introduce a relatively new marker, glycated albumin (GA), which can be used to complement A1C. First, for a better understanding of the characteristics of each marker, we sort the similarities and differences of glycemic control markers as well as the characteristics of each marker. Second, we point out the limitation of A1C, introduce GA as an alternative indicator, and discuss the limitations of GA. Finally, we summarize important evidence regarding the utility of GA. We hope that this review provides useful information that permits more effective usage of GA as well as other glycemic control markers.

Time in range correlates glycated albumin measured immediately after 2 weeks of continuous glucose monitoring

AIMS

Time in range (TIR), an index of glycemic control and also blood glucose fluctuation, obtained from continuous glucose monitoring (CGM), has been increasing its importance along with the spread of CGM in recent years. For a while, glycated albumin (GA) has been also used as a glycemic control index during about 2-weeks in routine clinical practice. It has not yet been confirmed under optimal condition whether TIR and GA correlates. Clarification of the correlation between TIR and GA, which was measured immediately after 2-weeks of CGM, might be a finding that further supports the utility of TIR.

METHODS

GA was measured at the conclusion of 2-week CGM in 71 diabetes outpatients at our hospital, and the correlation between GA and indices such as TIR obtained from CGM was statistically analyzed.

RESULTS

It was found that TIR and time above range (TAR) were significantly correlated with GA. Upon performing multiple regression analysis, TIR, TAR and BMI. indicated a significant regression coefficient with respect to GA.

CONCLUSIONS

These findings further support the utility of TIR as a marker of glycemic control that it might also be correlated with GA, and also suggest a relation between GA and blood glucose fluctuation.

Correlations Between Glycemic Parameters Obtained from Continuous Glucose Monitoring and Hemoglobin A1c and Glycoalbumin Levels in Type 2 Diabetes Mellitus

It is difficult to detect glycemic excursions using CGM in daily clinical practice. We retrospectively analyzed CGM data in type T2DM to define the correlations between HbA1c and GA levels at admission and the parameters representing glycemic excursions measured by CGM, including the mean amplitude of glycemic excursions (MAGE) and standard deviation (SD). The MAGE correlated significantly with GA and HbA1c, but not with the GA/HbA1c ratio. The SD correlated significantly with GA, HbA1c, and GA/HbA1c. Multivariate analysis identified the GA value to be the most reflective of MAGE. Patients were divided into 2 groups using a MAGE cutoff value of 75 mg/dl, which reflects stable diabetes. There was a significant difference in GA, but not HbA1c, between the groups with low and high mean amplitudes of glycemic excursions. Receiver operating characteristic curve analysis indicated that the cutoff for GA for identifying patients with MAGE of ≤75 mg/dl was 18.1%. Our study identified GA to be the most reflective of glycemic excursions in patients with T2DM. GA can be a useful index of glycemic excursions and treatment optimization to prevent arteriosclerosis.

Recent Updates and Advances in the Use of Glycated Albumin for the Diagnosis and Monitoring of Diabetes and Renal, Cerebro- and Cardio-Metabolic Diseases

Diabetes mellitus is a heterogeneous and dysmetabolic chronic disease in which the laboratory plays a fundamental role, from diagnosis to monitoring therapy and studying complications. Early diagnosis and good glycemic control should start as early as possible to delay and prevent metabolic and cardio-vascular complications secondary to this disease. Glycated hemoglobin is currently used as the reference parameter. The accuracy of the glycated hemoglobin dosage may be compromised in subjects suffering from chronic renal failure and terminal nephropathy, affected by the reduction in the survival of erythrocytes, with consequent decrease in the time available for glucose to attach to the hemoglobin. In the presence of these renal comorbidities as well as hemoglobinopathies and pregnancy, glycated hemoglobin is not reliable. In such conditions, dosage of glycated albumin can help. Glycated albumin is not only useful for short-term diagnosis and monitoring but predicts the risk of diabetes, even in the presence of euglycemia. This protein is modified in subjects who do not yet have a glycemic alteration but, as a predictive factor, heralds the risk of diabetic disease. This review summarizes the importance of glycated albumin as a biomarker for predicting and stratifying the cardiovascular risk linked to multiorgan metabolic alterations.

Association of Glucagon With Obesity, Glycemic Control and Renal Function in Adults With Type 2 Diabetes Mellitus

OBJECTIVES

In this study, we used a double-antibody sandwich enzyme-linked immunosorbent assay to assess the association between blood glucagon levels and indices of obesity, glycemic control and renal function in patients with type 2 diabetes mellitus (T2DM).

METHODS

This investigation was a cross-sectional study on inpatients with T2DM who had plasma glucagon levels measured during hospitalization. Associations of fasting glucagon levels (G₀), 120-minute postbreakfast plasma glucagon (G₁₂₀), fasting glucagon/C-peptide ratio (G₀/CPR₀) and postbreakfast glucagon/C-peptide ratio (G₁₂₀/CPR₁₂₀) with clinical data were evaluated using multiple regression analysis.

RESULTS

A total of 345 patients were enrolled in the study. G₀, and G₁₂₀ were significantly and positively associated with serum C-peptide levels. Moreover, G₀ and G₁₂₀ were positively associated with waist circumference, and G₀ was negatively associated with duration of diabetes mellitus. Interestingly, both G₀ and G₁₂₀ were negatively associated with the estimated glomerular filtration rate. In addition, G₁₂₀/CPR₁₂₀ was positively associated with duration of diabetes mellitus and glycoalbumin levels.

CONCLUSIONS

The balance between glucagon and insulin secretion is significantly associated with abdominal obesity and important for maintaining glucose homeostasis. Postprandial hyperglucagonemia could also be related to deterioration of renal function.

Single Amino Acid Mutation of Pyranose 2-Oxidase Results in Increased Specificity for Diabetes Biomarker 1,5-Anhydro-D-Glucitol

Pyranose 2-oxidases catalyze the oxidation of various pyranose sugars at the C2 position. However, their potential application for detecting sugars other than glucose in blood is hindered by relatively high activity towards glucose. In this study, in order to find a mutant enzyme with enhanced specificity for 1,5-anhydro-D-glucitol (1,5-AG), which is a biomarker for diabetes mellitus, we conducted site-directed mutagenesis of pyranose 2-oxidase from the basidiomycete Phanerochaete chrysosporium ( Pc POX). Considering the three-dimensional structure of the substrate-binding site of Pc POX and the structural difference between glucose and 1,5-AG, we selected alanine 551 of Pc POX as a target residue for mutation. Kinetic studies of the 19 mutants of Pc POX expressed as recombinant proteins in E. coli revealed that the ratio of k _cat / K _m for 1,5-AG to k _cat / K _m for glucose was three times higher for the A551L mutant than for wild-type Pc POX. Although the A551L mutant has lower specific activity towards each substrate than the wild-type enzyme, its increased specificity for 1,5-AG makes it a promising lead for the development of POX-based 1,5-AG detection systems.

Association between a biomarker of glucose spikes, 1,5-anhydroglucitol, and cancer mortality

INTRODUCTION

1,5-Anhydroglucitol (1,5-AG) is a biomarker of glucose spikes. To evaluate the effect of acute glucose excursions on cancer death, we clarified the association between 1,5-AG and cancer mortality among Japanese individuals with normal glucose tolerance.

RESEARCH DESIGN AND METHODS

We measured 1,5-AG in 6783 (2842 men, 3941 women) individuals with normal fasting and 2-hour plasma glucose who received a 75 g oral glucose tolerance test between 1994 and 2012. They were followed for mortality until August 2013. A systematic review of death certificates was used to confirm the cause of death. We divided the participants into four groups according to the quartile of 1,5-AG level at registration. We used Cox regression to clarify the association between 1,5-AG levels and cancer mortality with multivariate adjustment for possible confounders.

RESULTS

During the follow-up period (median, 10.0 years), 140 men and 109 women died of cancer. The HR for cancer mortality of the lowest quartile group was higher than that of the highest quartile group in men (HR, 2.62; 95% CI, 1.60 to 4.41) and in women (HR, 1.47; 95% CI, 0.88 to 2.47). These associations were not attenuated with further adjustment for HbA1c.

CONCLUSIONS

1,5-AG was associated with high risk of cancer mortality in Japanese men after adjustment for HbA1c.

Potential Markers of Dietary Glycemic Exposures for Sustained Dietary Interventions in Populations without Diabetes

There is considerable interest in dietary and other approaches to maintaining blood glucose concentrations within the normal range and minimizing exposure to postprandial hyperglycemic excursions. The accepted marker to evaluate the sustained maintenance of normal blood glucose concentrations is glycated hemoglobin A1c (HbA1c). However, although this is used in clinical practice to monitor glycemic control in patients with diabetes, it has a number of drawbacks as a marker of efficacy of dietary interventions that might beneficially affect glycemic control in people without diabetes. Other markers that reflect shorter-term glycemic exposures have been studied and proposed, but consensus on the use and relevance of these markers is lacking. We have carried out a systematic search for studies that have tested the responsiveness of 6 possible alternatives to HbA1c as markers of sustained variation in glycemic exposures and thus their potential applicability for use in dietary intervention trials in subjects without diabetes: 1,5-anhydroglucitol (1,5-AG), dicarbonyl stress, fructosamine, glycated albumin (GA), advanced glycated end products (AGEs), and metabolomic profiles. The results suggest that GA may be the most promising for this purpose, but values may be confounded by effects of fat mass. 1,5-AG and fructosamine are probably not sensitive enough to the range of variation in glycemic exposures observed in healthy individuals. Use of measures based on dicarbonyls, AGEs, or metabolomic profiles would require further research into possible specific molecular species of interest. At present, none of the markers considered here is sufficiently validated and sensitive for routine use in substantiating the effects of sustained variation in dietary glycemic exposures in people without diabetes.

Oxidized albumin in blood reflects the severity of multiple vascular complications in diabetes mellitus

Albumin has an oxidized form, known as non-mercaptalbumin (HNA), which reflects systemic oxidative stress. The association between serum HNA levels and diabetic complications are yet to be reported. In this cross-sectional study, we investigated 164 diabetic subjects to assess the correlation between HNA% (the proportion in the total albumin) and various clinical parameters. HNA% was significantly associated with the severity of multiple complications including neuropathy (23.3 ± 4.1% vs 26.2 ± 5.1%) and nephropathy (24.1 ± 3.9%, 24.6 ± 4.2%, 28.5 ± 6.1%, 31.3 ± 5.7%, 37.8 ± 2.9%, stage 1/2/3/4/5, respectively). These findings highlight the universal importance of oxidative stress, indicating HNA% potential as a versatile marker of the severity of diabetic complications.

Association of Hemoglobin A1c, 1,5-Anhydro-D-Glucitol and Glycated Albumin with Oxidative Stress in Type 2 Diabetes Mellitus Patients: A Cross-Sectional Study

INTRODUCTION

Oxidative stress plays a central role in the development and progression of vascular complications in patients with type 2 diabetes mellitus (T2DM). We have previously shown that markers of glucose variability evaluated by continuous glucose monitoring (CGM) are positively associated with oxidative stress in patients with T2DM. However, the evaluation of the glycemic variability by CGM remains a time- and money-consuming procedure. Therefore, this study investigated the independent correlates of oxidative stress among various other clinical markers routinely measured in primary care.

METHODS

This was a retrospective cross-sectional study with 234 T2DM patients to examine which clinical variables, including 1,5-anhydro-D-glucitol (1,5-AG) and glycated albumin (GA), were independently associated with oxidative stress. Oxidative stress was measured using the diacron-reactive oxygen metabolites (d-ROMs) test. The relationships between d-ROMs and clinical factors, such as blood glucose, glycated hemoglobin (HbA1c), 1,5-AG, GA, lipid parameters, and blood pressure, were examined.

RESULTS

Multiple stepwise regression analysis revealed that 1,5-AG (inversely), GA, triglycerides, use of metformin and being female were independently associated with d-ROMs. When patients with T2DM were stratified into two groups with HbA1c < 8.0% and HbA1c ≥ 8.0%, 1,5-AG (inversely), HbA1c, use of metformin and being female were independently associated with d-ROMs in diabetes patients with HbA1c < 8.0%, whereas GA, fasting plasma glucose and being female were independently associated with d-ROMs in patients with HbA1c ≥ 8.0%.

CONCLUSION

Our present study suggests that 1,5-AG and GA are the strongest correlates of oxidative stress in patients with well and poorly controlled T2DM, respectively.

Effect of Prestroke Glycemic Variability Estimated Glycated Albumin on Stroke Severity and Infarct Volume in Diabetic Patients Presenting With Acute Ischemic Stroke

Background: We investigated whether prestroke glycemic variability, represented by glycated albumin (GA), affects the initial stroke severity and infarct volume in diabetic patients presenting with acute ischemic stroke. Methods: We evaluated a total of 296 acute ischemic stroke patients with diabetes mellitus who were hospitalized within 48 h of stroke onset. GA was measured in all acute ischemic stroke patients consecutively during the study period. The primary outcome was the initial National Institute Health Stroke Scale (NIHSS) score. The secondary outcome was infarct volume on diffusion-weighted imaging, which was performed within 24 h of stroke onset. Higher GA (≥16.0%) was determined to reflect glycemic fluctuation prior to ischemic stroke. Results: The number of patients with higher GA was 217 (73.3%). The prevalence of a severe initial NIHSS score (>14) was higher in patients with higher GA than in those with lower GA (3.8% vs. 15.7%, p = 0.01). The proportion of participants in the highest quartile of infarct volume was higher in the higher GA group (11.4% vs. 36.4%, p < 0.001). A multivariable analysis showed that higher GA was significantly associated with a severe NIHSS score (odds ratio, [95% confidence interval], 7.99 [1.75-36.45]) and large infarct volume (3.76 [1.05-13.45]). Conclusions: Prestroke glucose variability estimated by GA was associated with an increased risk of severe initial stroke severity and large infarct volume in acute ischemic stroke patients with diabetes mellitus.

The association between glycated albumin, glycohemoglobin, and glycated albumin to glycohemoglobin ratio in diabetic retinopathy of prediabetes

Prediabetes increased risk of diabetes and diabetes-related macrovascular and microvascular complication. Glycohemoglobin (HbA_1c ) is clinically used as the gold standard for glycemic control of diabetes. Glycated albumin (GA) is an early Amadori-type glycation protein between glucose and serum albumin, which changes in a shorter period of time than HbA_1c and is superior to HbA_1c in reflecting fluctuations in blood glucose. In this study, we aim to assess the predictive value of GA and glycohemoglobin (HbA1c) on a progression of diabetic retinopathy (DR) in prediabetic patients in Taiwan. This study was conducted at the outpatient department of a regional hospital in Southern Taiwan, and recruited 291 patients with prediabetes from January 2016 to February 2017. Blood and urine samples were obtained from all patients after fasting for 12 hours within 1 month of enrollment. The mean age is 62.5 ± 13.0 years and there are 161 males and 130 females. A total of 24.1% of patients have DR. The average value of GA and HbA1c are 14.6% ± 2.8% and 6.0% ± 0.4%, respectively. Old age, male, high systolic blood pressure, high HbA_1C , and low total cholesterol are significantly associated with DR in patients with pre-DM. Therefore, in the prediabetic populations, high HbA_1C, but not GA nor GA/HbA_1C ratio, is significantly associated with DR.

Higher blood glucose and larger fluctuations detected postoperatively using continuous glucose monitoring: a preliminary study following total knee or hip arthroplasty

BACKGROUND

The control of diabetes mellitus (DM) should help reduce the incidence of periprosthetic joint infection (PJI). Self-monitoring of blood glucose (SMBG) concentration is usually undertaken at fixed time-points. Therefore, the extent of postoperative blood glucose fluctuation might be underestimated. To provide a more comprehensive assessment, continuous glucose monitoring (CGM) is beginning to be used. However, no previous studies have evaluated blood glucose concentrations using CGM following orthopedic surgery. Therefore, the differences between the maximum blood glucose concentrations measured using SMBG and CGM, and the mean amplitude of the glycemic fluctuation in patients with frank diabetes mellitus (DM) or pre-diabetes were evaluated. Blood glucose was measured in 20 patients who had undergone total hip or total knee arthroplasty (12 patients with DM and eight with pre-diabetes). Patients were fitted with a CGM device in the operating room, which was worn for 6 days postoperatively, and used to evaluate blood glucose concentration continuously. SMBG was performed simultaneously for the same period.

RESULTS

The mean difference between the maximum blood glucose concentrations measured using SMBG and CGM was 25.0 ± 20.3 mg/dl (range, - 17 to 81 mg/dl), with the concentrations measured using CGM tending to be higher than those measured using SMBG (P = 0.04). Blood glucose concentrations measured using CGM tended to be higher than those measured using SMBG until postoperative day 2, and to decrease gradually after postoperative day 4. There were no significant differences in the standard deviation of the blood glucose concentrations between the two groups.

CONCLUSIONS

Blood glucose concentrations > 200 mg/dl and larger fluctuations were more frequently recorded using CGM than SMBG, especially until postoperative day 2. Thus, CGM is more useful for the identification of high blood glucose concentrations and larger fluctuations. However, this information was not provided in real time.

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.

Effects of Insulin Lispro Mix 25 and Insulin Lispro Mix 50 on Postprandial Glucose Excursion in Patients with Type 2 Diabetes: A Prospective, Open-Label, Randomized Clinical Trial

INTRODUCTION

We compared the effects of insulin lispro mix 25 (LM25) and insulin lispro mix 50 (LM50) on postprandial glucose excursion in patients with type 2 diabetes mellitus (T2DM).

METHODS

In this randomized, open-label, investigator-initiated trial, 81 T2DM patients treated with premixed human insulin 70/30 (PHI70/30) for more than 90 days were randomly divided into two groups and received a crossover protocol of either LM25 or LM50 twice daily for 16 weeks. Continuous glucose monitoring (CGM) was performed for 72 h at baseline and at the end of each treatment phase to evaluate glycemic excursions in the subjects.

RESULTS

The LM50 regimen resulted in significantly smaller postprandial glycemic excursions than the LM25 regimen after breakfast (1.3 ± 2.5 vs. 2.4 ± 2.6 mmol/L, P = 0.046) and dinner (1.5 ± 2.8 vs. 2.8 ± 2.4 mmol/L, P = 0.036). Glycosylated hemoglobin levels were similar for the patients on the three regimens. The percentage of patients who achieved their glycosylated hemoglobin target was significantly higher for the LM25 and LM50 regimens than for the PHI70/30 regimen, regardless of whether the target was set at 7.0% or 6.5%. The proportion of the patients who were hypoglycemic for a high percentage (> 10%) of the time was lower for the LM50 regimen than for the LM25 and PHI70/30 regimens.

CONCLUSIONS

LM50 may provide better glycemic excursion control after breakfast and dinner than LM25 in T2DM patients.

TRIAL REGISTRATION

http://www.chictr.org.cn # ChiCTR-TTRCC-12002516.

FUNDING

Lilly Suzhou Pharmaceutical Co., Ltd. (Shanghai Branch, China) and National Key Program of Clinical Science of China (WBYZ 2011-873).

Serum Fructosamine: A Simple and Inexpensive Test for Assessing Preoperative Glycemic Control

BACKGROUND

Although the medical community acknowledges the importance of preoperative glycemic control, the literature is inconclusive and the proper metric for assessment of glycemic control remains unclear. Serum fructosamine reflects the mean glycemic control in a shorter time period compared with glycated hemoglobin (HbA1c). Our aim was to examine its role in predicting adverse outcomes following total joint arthroplasty.

METHODS

Between 2012 and 2013, we screened all patients undergoing total joint arthroplasty preoperatively using serum HbA1c, fructosamine, and blood glucose levels. On the basis of the recommendations of the American Diabetes Association, 7% was chosen as the cutoff for HbA1c being indicative of poor glycemic control. This threshold correlated with a fructosamine level of 292 μmol/L. All patients were followed and total joint arthroplasty complications were evaluated. We were particularly interested in retrieving details on surgical-site infection (superficial and deep). Patients with fructosamine levels of ≥292 μmol/L were compared with those with fructosamine levels of <292 μmol/L. Complications were evaluated in a univariate analysis followed by a stepwise logistic regression analysis.

RESULTS

A total of 829 patients undergoing primary total joint arthroplasty were included in the present study. There were 119 patients (14.4%) with a history of diabetes and 308 patients (37.2%) with HbA1c levels in the prediabetic range. Overall, 51 patients had fructosamine levels of ≥292 μmol/L. Twenty patients (39.2%) had a fructosamine level of ≥292 μmol/L but did not have an HbA1c level of ≥7%. Patients with fructosamine levels of ≥292 μmol/L had a significantly higher risk for deep infection (adjusted odds ratio [OR], 6.2 [95% confidence interval (CI), 1.6 to 24.0]; p = 0.009), readmission (adjusted OR, 3.0 [95% CI, 1.1 to 8.1]; p = 0.03), and reoperation (adjusted OR, 3.4 [95% CI, 1.2 to 9.2]; p = 0.02). In the current study with the given sample size, HbA1c levels of ≥7% failed to show any significant correlation with deep infection (p = 0.14), readmission (p = 1.0), or reoperation (p = 0.7).

CONCLUSIONS

Serum fructosamine is a simple and inexpensive test that appears to be a good predictor of adverse outcome in patients with known diabetes and those with unrecognized diabetes or hyperglycemia. Our findings suggest that fructosamine can serve as an alternative to HbA1c in the setting of preoperative glycemic assessment.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Glycated albumin and its variability as an indicator of cardiovascular autonomic neuropathy development in type 2 diabetic patients

BACKGROUND

We investigated whether glycated albumin (GA) and its variability are associated with cardiovascular autonomic neuropathy (CAN) and further compared their associations with glycated hemoglobin (HbA1c).

METHODS

This retrospective longitudinal study included 498 type 2 diabetic patients without CAN. CAN was defined as at least two abnormal results in parasympathetic tests or presence of orthostatic hypotension. The mean, standard deviation (SD), and coefficient of variance (CV) were calculated from consecutively measured GA (median 7 times) and HbA1c levels (median 8 times) over 2 years. Logistic regression analysis was used to compare the associations between CAN and GA- or HbA1c-related parameters. Receiver operating characteristic (ROC) curve analysis was used to compare the predictive power for CAN between GA- and HbA1c-related parameters.

RESULTS

A total of 53 subjects (10.6%) developed CAN over 2 years. The mean, SD, and CV of GA or HbA1c were significantly higher in subjects with CAN. Higher mean GA and GA variability were associated with the risk of developing CAN, independent of conventional risk factors and HbA1c. In ROC curve analysis, the SD and CV of GA showed higher predictive value for CAN compared to the SD and CV of HbA1c, whereas the predictive value of mean GA did not differ from that of mean HbA1c. The mean, SD, and CV of GA showed additive predictive power to detect CAN development along with mean HbA1c.

CONCLUSIONS

Higher serum GA and its variability are significantly associated with the risk of developing CAN. Serum GA might be a useful indicator for diabetic complications and can enhance HbA1c's modest clinical prediction for CAN.

Comparison of Glucose Area Under the Curve Measured Using Minimally Invasive Interstitial Fluid Extraction Technology with Continuous Glucose Monitoring System in Diabetic Patients

BACKGROUND

Continuous glucose monitoring (CGM) is reported to be a useful technique, but difficult or inconvenient for some patients and institutions. We are developing a glucose area under the curve (AUC) monitoring system without blood sampling using a minimally invasive interstitial fluid extraction technology (MIET). Here we evaluated the accuracy of interstitial fluid glucose (IG) AUC measured by MIET in patients with diabetes for an extended time interval and the potency of detecting hyperglycemia using CGM data as a reference.

METHODS

Thirty-eight inpatients with diabetes undergoing CGM were enrolled. MIET comprised a pretreatment step using a plastic microneedle array and glucose accumulation step with a hydrogel patch, which was placed on two sites from 9:00 AM to 5:00 PM or from 10:00 PM to 6:00 AM. IG AUC was calculated by accumulated glucose extracted by hydrogel patches using sodium ion as standard.

RESULTS

A significant correlation was observed between the predicted AUC by MIET and CGM in daytime (r=0.76) and nighttime (r=0.82). The optimal cutoff for the IG AUC value of MIET to predict hyperglycemia over 200 mg/dL measured by CGM for 8 hours was 1,067.3 mg·hr/dL with 88.2% sensitivity and 81.5% specificity.

CONCLUSION

We showed that 8-hour IG AUC levels using MIET were valuable in estimating the blood glucose AUC without blood sampling. The results also supported the concept of using this technique for evaluating glucose excursion and for screening hyperglycemia during 8 hours in patients with diabetes at any time of day.

Alternative Measures of Hyperglycemia and Risk of Alzheimer's Disease in the Community: The Hisayama Study

CONTEXT AND OBJECTIVE

We investigated the associations of hemoglobin A1c (HbA1c), glycated albumin (GA), GA/HbA1c ratio, and 1,5-anhydroglucitol (1,5-AG) with the development of Alzheimer's disease (AD).

DESIGN AND PARTICIPANTS

A total of 1187 community-dwelling Japanese subjects aged ≥65 years without dementia were followed up for an average of 4.8 years.

RESULTS

The age- and sex-adjusted incidence of AD increased significantly with higher quartiles of GA/HbA1c ratio, and a similar tendency was seen for GA, whereas no such association was observed for HbA1c and 1,5-AG. After adjusting for potential confounding factors, positive association of GA/HbA1c ratio with the risk of AD remained significant: the multivariable-adjusted hazard ratio (HR) was significantly higher in the third [HR = 2.11, 95% confidence interval (CI) = 1.16 to 3.82] and fourth (HR = 2.01, 95% CI = 1.09 to 3.68) quartile than in the first quartile. Among subjects with normal glucose tolerance, those with high GA/HbA1c ratio had a higher risk of AD than those with low GA/HbA1c ratio (HR = 1.82, 95% CI = 1.05 to 3.16), and a similar tendency was found in those with glucose intolerance (HR = 1.73, 95% CI = 0.96 to 3.13). No such associations were observed for HbA1c, GA, and 1,5-AG, regardless of glucose tolerance status.

CONCLUSIONS

Our findings suggest that elevated GA/HbA1c ratio-but not HbA1c, GA, or 1,5-AG level-is significantly associated with the risk of AD in subjects both with and without glucose intolerance. GA/HbA1c ratio may be a useful biomarker for predicting incident AD.

Serum albumin-adjusted glycated albumin as a better indicator of glycemic control in Type 2 diabetes mellitus patients with short duration of hemodialysis

AIMS

Serum albumin-adjusted glycated albumin (adjusted GA) is reportedly a better predictor of mortality than GA in patients with Type 2 diabetes mellitus (T2DM) on hemodialysis (HD). We compared how accurately GA and adjusted GA reflected glycemic control in these patients.

METHODS

We enrolled 31 patients with T2DM on HD. They were divided into two groups according to duration of HD: ≤6months (short HD group, N=16) and >6months (long HD group, N=15). GA or adjusted GA and parameters of glycemic control obtained by continuous glucose monitoring were measured, and the correlations between these were analyzed.

RESULTS

GA and adjusted GA were significantly correlated with mean glucose levels (r=0.400, P=0.025 and r=0.508, P=0.0037) in all patients. Similar results were obtained in the long HD group (GA: r=0.554, P=0.032; adjusted GA: r=0.604, P=0.017). However, in the short HD group, adjusted GA (r=0.502, P=0.047) but not GA (r=0.340, P=0.20) was significantly correlated with mean glucose levels.

CONCLUSIONS

Adjusted GA may be a better indicator than GA for evaluating glycemic control in T2DM patients with short duration of HD.

Glycated albumin: a potential biomarker in diabetes

Diabetes mellitus (DM) is a chronic and metabolic disease that presents a high global incidence. Glycated hemoglobin (A1C) is the reference test for long-term glucose monitoring, and it exhibits an association with diabetic chronic complications. However, A1C is not recommended in clinical situations which may interfere with the metabolism of hemoglobin, such as in hemolytic, secondary or iron deficiency anemia, hemoglobinopathies, pregnancy, and uremia. The glycated albumin (GA) is a test that reflects short-term glycemia and is not influenced by situations that falsely alter A1C levels. GA is the higher glycated portion of fructosamine. It is measured by a standardized enzymatic methodology, easy and fast to perform. These laboratory characteristics have ensured the highlight of GA in studies from the last decade, as a marker of monitoring and screening for DM, as well as a predictor of long-term outcomes of the disease. The aim of this review was to discuss the physiological and biochemistry characteristics of the GA, as well as its clinical utility in DM.

Glycated albumin indicates peripheral diabetic neuropathy

AIMS

We investigated associations between serum levels of glycated albumin (GA) and glycated hemoglobin (HbA1c) and the presence of diabetic peripheral neuropathy (DPN) in patients with type 1 diabetes mellitus (T1DM).

METHODS

Between September 2009 and April 2015, we evaluated 314 patients with T1DM in the Endocrinology Department of Shengjing Hospital of China Medical University. We divided the patients into the DPN group (n = 72) and the non-DPN group (n = 242), on the basis of the presence of DPN.

RESULTS

The DPN group had significantly higher GA values than the non-DPN group. After univariate logistic regression, we selected several factors for further analysis: HbA1c, GA, duration of T1DM, body mass index, smoking, hypertension, and the presence of diabetic complications, including nephropathy, retinopathy, and cardiovascular disease. We performed a multivariate logistic regression analysis to examine the association between the presence of DPN and each of these variables. We identified GA, HbA1c, hypertension, smoking, retinopathy, and cardiovascular disease as independent variables for indicating the presence of DPN. Results of a receiver operating characteristic curve analysis revealed that the area under the curve of GA (0.771) was larger than that of HbA1c (0.629). We defined the cutoff value of GA as 23.5 % (sensitivity 0.764, specificity 0.661) and the cutoff value of HbA1c as 8.45 % (sensitivity 0.667, specificity 0.595) for predicting DPN in patients with T1DM.

CONCLUSIONS

GA may be a better indicative marker of DPN in patients with T1DM than HbA1c.

Effects of alogliptin on the ratio of glycated albumin to HbA1c in patients with type 2 diabetes mellitus

The ratio of glycated albumin (GA) to HbA1c (the GA/HbA1c ratio) has been used as a glycemic control indicator that reflects postprandial plasma glucose levels or glycemic variability. In this study, we investigated the effects of alogliptin, a DPP-4 inhibitor, on the GA/HbA1c ratio in patients with type 2 diabetes mellitus. Thirty-eight patients with type 2 diabetes mellitus whose glycemic control was stable were enrolled, and alogliptin (12.5 or 25 mg/day) was then administered to them for 24 weeks. HbA1c and GA levels both significantly decreased after 24 weeks (P < 0.0001), whereas the GA/HbA1c ratio did not (P = 0.129). No correlation was observed between the change in the GA/HbA1c ratio (the ΔGA/HbA1c ratio) and HbA1c or GA level before the administration of alogliptin; however, a negative correlation was found between the ΔGA/HbA1c ratio and the GA/HbA1c ratio before the administration of alogliptin (R = -0.322, P = 0.049). Although the GA/HbA1c ratio in the low-value group (<2.80) was not significantly affected by the administration of alogliptin, that in the high-value group (≥2.80) significantly decreased (P = 0.008). The administration of alogliptin significantly decreased the GA/HbA1c ratio in the high-value group after 24 weeks. Alogliptin may be more useful for patients with high postprandial plasma glucose levels than in those with low postplandial plasma glucose levels.

The establishment of biological reference intervals of nontraditional glycemic markers in a Chinese population

BACKGROUND

We established the reference intervals for glycated albumin (GA), fructosamine (FA), and 1,5-anhydroglucitol (1,5-AG) in a Chinese healthy population.

METHODS

This study enrolled a total of 458 eligible reference individuals, consisted of 226 men and 232 women, aged from 20~79 years (median age 43 years), who attending routine healthy checks. We stratified the subjects according to gender (males and females) and age (20-39, 40-59, and 60-79 years), and combined statistical methods with Lahti algorithm, as well as appropriate clinical consideration, to judge whether partitioning for data was needed.

RESULTS

Glycated albumin levels between males and females were statistically different (P<.001), but the absolute difference between the upper reference limits was only 0.31%, which was too small to be clinically relevant. GA levels across the three age groups were statistically different (P<.001), and Lahti algorithm suggested partitioning for 20-59 and 60-79 years, which reference intervals were 10.38%-13.89% and 10.23%-14.79%, respectively. 1,5-AG levels in males were significant higher than females (P<.001), and absolute difference was 51 μmol/L (8.5 μg/mL) in mean level. Thus, partitioning for gender was needed. Reference intervals for 1,5-AG were 107-367 μmol/L for males and 79-306 μmol/L for females. The absolute difference of the lower reference limits for FA was only 7 μmol/L between males and females. FA levels across the three age groups were not statistically different (P>.05). The reference interval for FA was 220-298 μmol/L.

CONCLUSION

New reference intervals for nontraditional glycemic markers were established based on a Chinese population.

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.

Impact of glucose fluctuation on acute cerebral infarction in type 2 diabetes

OBJECTIVE

This study aimed to describe the frequency and temporal profile of acute cerebral infarction (ACI) using a continuous glucose monitoring system (CGMS) in patients with and without type 2 diabetes mellitus (T2DM) and explore the impact of blood glucose fluctuations on the short-term prognosis of ACI.

METHODS

The subjects were divided into four groups: T2DM with acute cerebral infarction (DMCI, Group A, n=56); T2DM without acute cerebral infarction (DM-NCI, Group B, n=36); Acute cerebral infarction patients without T2DM (NDM-CI, Group C, n=54); Healthy control group (NG, Group D, n=36). The National Institutes of Health Stoke Scale (NIHSS) and modified Rankin scale (mRs) were collected in Group A and C. All subjects were monitored for 72 hours using the CGMS. Indices such as fasting blood glucose (FBG) and mean amplitude of glycemic excursions (MAGE) were calculated. Glycemic excursions were compared between Group A, B, C and Group D, respectively. Multiple linear regression analysis and logistic analysis was applied.

RESULTS

MAGE is related to NIHSS, homocysteine (HCY), HOMA-IR, FBG, CRP and IMT, while NIHSS is related to CRP, HCY, HOMA-IR, IMT. The factors impacting the short-term prognosis of ACI were NIHSS, HBA1C and MAGE.

CONCLUSION

Larger glucose fluctuations are associated with more stroke risk factors and are associated with a poorer short-term prognosis. More attention should be paid to glucose fluctuations in patients with ACI and a history of T2DM.

Plasma Glycated Albumin Levels Clearly Detect Hearing Loss and Atherosclerosis in Patients with Impaired Fasting Glucose

OBJECTIVE

To describe the relationship between atherosclerosis and hearing thresholds in prediabetic patients with impaired fasting glucose (IFG) and to determine the efficacy of glycated albumin in predicting carotid artery atherosclerosis in patients with isolated IFG.

SUBJECTS AND METHODS

The study included 82 patients (aged 53.73-80 years) divided into two groups based on fasting glucose levels, the IFG group: 59 patients (32 females, 54.2%), and the normal fasting plasma glucose level group: 23 patients (12 females, 52.2%). Patients underwent audiological testing to determine hearing thresholds, and carotid intima-media thickness (CIMT) was measured using carotid artery Doppler sonography. Multivariate analyses were performed to determine whether or not the plasma glycated albumin levels could predict hearing loss and CIMT.

RESULTS

Patients in the IFG group (mean age: 59.8 ± 9.5 years) had higher hearing thresholds and pure-tone average scores (PTA) than those in the group with normal glucose levels (mean age: 56.2 ± 10.1 years) (left ear: 27.65 ± 8.85 vs. 25.75 ± 21.96 dB, p = 0.021; right ear: 29.22 ± 8.51 vs. 22.39 ± 6.99 dB, p = 0.001). The CIMT was significantly higher in the IFG group than the control group (0.75 ± 0.26 vs. 0.56 ± 0.16 mm, p < 0.001 for the left and 0.74 ± 0.26 vs. 0.51 ± 0.19 mm, p < 0.001 for the right carotid arteries). Glycated albumin levels were independently related with increased CIMT (left CIMT: r = 0.32, p = 0.003; right CIMT: r = 0.42, p < 0.001), and serum glycated albumin levels were significantly associated with PTA (left ear: r = 0.28, p = 0.01; right ear: r = 0.30, p = 0.006).

CONCLUSION

Sensorineural hearing loss was more common in patients with IFG. Plasma glycated albumin levels were strongly correlated with CIMT and carotid plaques as a marker of atherosclerosis and with hearing impairment thought to develop due to atherosclerosis in patients with IFG.

Effect of Switching from Sulphonylurea to Repaglinide Twice or Three Times Daily for 4 Months on Glycemic Control in Japanese Patients with Type 2 Diabetes

Objective Switching from sulfonylureas to repaglinide in patients with type 2 diabetes improves glycemic control; however, the optimal dosage has not been fully evaluated. We designed to show that repaglinide was equivalent to sulfonylurea in Japanese patients with type 2 diabetes. We herein evaluated whether we could switch from sulfonylureas to repaglinide twice or thrice daily in Japanese adult patients who had been treated with anti-diabetic drugs, including sulfonylureas, and whose conditions were moderately well-controlled. Methods A total of 78 patients taking less than half the Japanese maximum dose of sulfonylurea were randomized into three groups: 26 in group A (switching from sulfonylureas to taking 0.25 or 0.5 mg of repaglinide just before breakfast and dinner twice daily), 27 in group B (switching from sulfonylureas to taking 0.25 or 0.5 mg of repaglinide just before meals thrice daily), and 25 in group C (continuing to take sulfonylurea). Blood samples were collected at 0, 1, 2, 3, and 4 months following the initiation of the maintenance period. Results The HbA1c and glycoalbumin levels did not significantly differ among the three groups after 4 months of treatment. Conclusion With the assumption that 1 mg of glimepiride is equivalent to 1.25 mg of glibenclamide or 40 mg of gliclazide, the administration of repaglinide (0.44 mg/meal) twice and thrice daily is similar to the efficacy of sulfonylurea (glimepiride 1.63-1.98 mg/day) after four months of treatment in Japanese patients with moderately well-controlled type 2 diabetes (HbA1c, 7-7.5%).

Glycated Albumin Predicts Long-term Survival in Patients Undergoing Hemodialysis

BACKGROUND

In patients with advanced renal dysfunction undergoing maintenance hemodialysis, glycated albumin (GA) levels may be more representative of blood glucose levels than hemoglobin A1C levels. The aim of this study was to determine the predictive power of GA levels on long-term survival in hemodialysis patients.

METHODS

A total of 176 patients with a mean age of 68.2 years were enrolled. The median duration of follow-up was 51.0 months. Receiver-operating characteristic curve analysis was utilized to determine the optimal cutoff value. We examined the cumulative survival rate by Kaplan-Meier estimates and the influence of known survival factors with the multivariate Cox proportional-hazard regression model.

RESULTS

In the whole patient group, cumulative survival in the low GA group was better than in the high GA group (p=0.030), with more prominence in those aged <70 years (p=0.029). In subgroup analysis, both diabetic (DM) and non-DM patients with low GA had a better cumulative survival compared with those with high GA. The risk of mortality increased by 3.0% for each 1% increase in serum GA level in all patients undergoing hemodialysis.

CONCLUSIONS

In addition to serving as a glycemic control marker, GA levels may be useful for evaluating the risk of death in both DM and non-DM patients on hemodialysis.

Glycated Albumin Levels in Patients with Type 2 Diabetes Increase Relative to HbA1c with Time

We recently reported that glycated albumin (GA) is increased in subjects with longer duration of diabetes and with decreased insulin secretory function. Based on this, we investigated whether GA increases with time relative to glycated hemoglobin (HbA1c) and the association between GA and beta-cell function. We analyzed 340 type 2 diabetes patients whose serum GA and HbA1c levels had been repeatedly measured over 4 years. We assessed the pattern of changes with time in glycemic indices (GA, HbA1c, and GA/HbA1c ratio) and their relationship with beta-cell function. In all patients, glycemic indices decreased and maintained low levels around 15 and 27 months. However, from 39 months to 51 months, GA significantly increased but HbA1c tended to increase without statistical significance. We defined ΔGA/HbA1c as the difference between the nadir point (at 15 to 27 months) and the end point (at 39 to 51 months) and found that ΔGA/HbA1c was positively correlated with diabetes duration and negatively related to beta-cell function. In multivariable linear regression analyses, ΔGA/HbA1c was independently associated with diabetes duration. In conclusion, this study demonstrated that serum GA levels increase relative to HbA1c levels with time.

Glycated albumin as a diagnostic tool for diabetes in a general Japanese population

OBJECTIVE

Diabetes mellitus is a major cause of cardiovascular, kidney, neurologic, and eye diseases, and may be preventable in some cases by lifestyle modification. Screening tests for diabetes mellitus include fasting plasma glucose (FPG) and glycated hemoglobin (HbA1c). Our objective was to evaluate the utility of plasma glycated albumin (GA) in the diagnosis of diabetes mellitus.

DESIGN AND METHODS

A cross-sectional, community-based population study of 908 non-diabetic Japanese residents was conducted. Of these subjects, 176 with FPG value between 5.5 and 6.9mmol/l, and an HbA1c level of <6.5% received an oral glucose tolerance test (OGTT).

RESULTS

The OGTT results were used for the diagnosis of diabetes mellitus using World Health Organization criteria. Receiver operating characteristic (ROC) analyses demonstrated that optimal threshold values for the diagnosis of diabetes in this population were 15.2% for GA and 5.9% for HbA1c, respectively. Using these cutoff levels, the sensitivity of GA at 62.1% for detecting diabetes was the same as that of HbA1c. However the specificity for GA for detecting diabetes was 61.9%, while for HbA1c it was higher at 66.7%.

CONCLUSIONS

Our results indicate that the measurement of glycated albumin may serve as a useful screening test for diabetes in a general Japanese population.

Advantages and pitfalls of fructosamine and glycated albumin in the diagnosis and treatment of diabetes

The efficient diagnosis and accurate monitoring of diabetic patients are cornerstones for reducing the risk of diabetic complications. The current diagnostic and prognostic strategies in diabetes are mainly based on two tests, plasma (or capillary) glucose and glycated hemoglobin (HbA1c). Nevertheless, these measures are not foolproof, and their clinical usefulness is biased by a number of clinical and analytical factors. The introduction of other indices of glucose homeostasis in clinical practice such as fructosamine and glycated albumin (GA) may be regarded as an attractive alternative, especially in patients in whom the measurement of HbA1c may be biased or even unreliable. These include patients with rapid changes of glucose homeostasis and larger glycemic excursions, and patients with red blood cell disorders and renal disease. According to available evidence, the overall diagnostic efficiency of GA seems superior to that of fructosamine throughout a broad range of clinical settings. The current method for measuring GA is also better standardized and less vulnerable to preanalytical variables than those used for assessing fructosamine. Additional advantages of GA over HbA1c are represented by lower reagent cost and being able to automate the GA analysis on many conventional laboratory instruments. Although further studies are needed to definitely establish that GA can complement or even replace conventional measures of glycemic control such as HbA1c, GA may help the clinical management of patients with diabetes in whom HbA1c values might be unreliable.