Glycated albumin and risk of death and hospitalizations in diabetic dialysis patients

Glycated Albumin and Adverse Clinical Outcomes in Patients With CKD: A Prospective Cohort Study

RATIONALE & OBJECTIVE

Hemoglobin A1c (HbA1c) is widely used to estimate glycemia, yet it is less reliable in patients with chronic kidney disease (CKD). There is growing interest in the complementary use of glycated albumin (GA) to improve glycemic monitoring and risk stratification. However, whether GA associates with clinical outcomes in a non-dialysis-dependent CKD population remains unknown.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

3,110 participants with CKD from the Chronic Renal Insufficiency Cohort study.

EXPOSURE

Baseline GA levels.

OUTCOME

Incident end-stage kidney disease (ESKD), cardiovascular disease (CVD) events, and all-cause mortality.

ANALYTICAL APPROACH

Cox proportional hazards regression.

RESULTS

Participant characteristics included mean age 59.0±10.8 SD years; 1,357 (43.6%) female; and 1,550 (49.8%) with diabetes. The median GA was 18.7% (IQR, 15.8%-23.3%). During an average 7.9-year follow-up, there were 980 ESKD events, 968 CVD events, and 1,084 deaths. Higher GA levels were associated with greater risks of all outcomes, regardless of diabetes status: hazard ratios for ESKD, CVD, and death among participants with the highest quartile compared with quartile 2 (reference) were 1.42 (95% CI, 1.19-1.69), 1.67 (95% CI, 1.39-2.01), and 1.63 (95% CI, 1.37-1.94), respectively. The associations with CVD and death appeared J-shaped, with increased risk also seen at the lowest GA levels. Among patients with coexisting CKD and diabetes, the associations of GA with outcomes remained significant even after adjusting for HbA1c. For each outcome, we observed a significant increase in the fraction of new prognostic information when both GA and HbA1c were added to models.

LIMITATIONS

Lack of longitudinal GA measurements; and HbA1c measurements were largely unavailable in participants without diabetes.

CONCLUSIONS

Among patients with CKD, GA levels were independently associated with risks of ESKD, CVD, and mortality, regardless of diabetes status. GA added prognostic value to HbA1c among patients with coexisting CKD and diabetes.

PLAIN-LANGUAGE SUMMARY

Hemoglobin A1c (HbA1c) is widely used to estimate glycemia, yet it is less reliable in patients with chronic kidney disease (CKD). There is growing interest in the complementary use of glycated albumin (GA) to improve glycemic monitoring and risk stratification. However, whether GA associates with clinical outcomes in a non-dialysis-dependent CKD population remains unknown. In this cohort study of 3,110 individuals with non-dialysis-dependent CKD, GA levels were independently associated with risks of end-stage kidney disease, cardiovascular disease (CVD), and mortality. The associations with CVD and mortality appeared to be J-shaped. Among patients with coexisting CKD and diabetes, GA added prognostic value to HbA1c. Thus, GA may be a valuable complementary test to HbA1c in patients with CKD.

The Correlation Between Glycation Gap and Renal Complications in Patients with Type 2 Diabetes Mellitus

Purpose

The aim of this study was to investigate the correlations between the glycation gap (GG) and renal complications such as urinary albumin-creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR) in type 2 diabetes mellitus patients.

Materials and Methods

A cross-sectional study was conducted on 104 individuals (52 males and 52 females), aged 36-93 years old. Fasting blood glucose (FBG), HbA1c, and serum fructosamine were measured simultaneously. GG was calculated as the difference between the measured and fructosamine-based predicted HbA1c levels (FHbA1c).

Results

There was a moderately positive correlation between HbA1c and fructosamine concentration (r = 0.488; p < 0.001). GG was positively correlated with UACR (r = 0.3275; p = 0.0007), negatively correlated with eGFR (r = -0.3400; p = 0.0004). HbA1c was positively correlated with UACR (r = 0.2437; p = 0.0127) but not correlated with eGFR (r = -0.444; p = 0.6542). Fructosamine has a positive correlation with eGFR (r = 0.2426; p = 0.0131) but not with UACR (r = -0.1021; p = 0.3025).

Conclusion

GG was positively correlated with UACR and inversely correlated with eGFR in type 2 Diabetes mellitus patients. This suggests that GG is a valuable index for predicting kidney complications due to diabetes.

Novel clinical relationships between time in range and microangiopathies in people with type 2 diabetes mellitus on hemodialysis

AIMS/HYPOTHESIS

We investigated associations among glucose time in range (TIR, 70-180 mg/dL), glycemic markers and prevalence of diabetic microangiopathy in people with diabetes undergoing hemodialysis (HD).

METHODS

A total of 107 people with type 2 diabetes undergoing HD (HbA_1c 6.4 %; glycated albumin [GA] 20.6 %) using continuous glucose monitoring were analyzed in this observational and cross-sectional study.

RESULTS

HbA_1c and GA levels significantly negatively correlated with TIR, and positively correlated with time rate of hyperglycemia, but not with time rate of hypoglycemia. TIR of 70 % corresponded to HbA_1c of 6.5 % and GA of 21.2 %. The estimated HbA_1c level corresponding to TIR of 70 % in this study was lower than that previously reported in people with diabetes without HD. The prevalence of diabetic neuropathy was not significantly different between people with TIR ≥ 70 % and those with TIR < 70 % (P = 0.1925), but the prevalence of diabetic retinopathy in people with TIR ≥ 70 % was significantly lower than in those with TIR < 70 % (P = 0.0071).

CONCLUSION/INTERPRETATION

TIR correlated with HbA_1c and GA levels in people with type 2 diabetes on HD. Additionally, a higher TIR resulted in a lower rate of diabetic retinopathy.

RESEARCH IN CONTEXT

What is already known about this subject? What is the key question? What are the new findings? How might this impact on clinical practice in the foreseeable future?

Narrative Review of glycaemic management in people with diabetes on peritoneal dialysis

There is an increasing number of people with diabetes on peritoneal dialysis (PD) worldwide. However, there is a lack of guidelines and clinical recommendations for managing glucose control in people with diabetes on PD. The aim of this review is to provide a summary of the relevant literature and highlight key clinical considerations with practical aspects in the management of diabetes in people undergoing PD. A formal systematic review was not conducted because of the lack of sufficient and suitable clinical studies. A literature search was performed using PubMed, MEDLINE, Central, Google Scholar and ClinicalTrials.gov., from 1980 through February 2022. The search was limited to publications in English. This narrative review and related guidance have been developed jointly by diabetologists and nephrologists, who reviewed all available current global evidence regarding the management of diabetes in people on PD.We focus on the importance of individualized care for people with diabetes on PD, the burden of hypoglycemia, glycemic variability in the context of PD and treatment choices for optimizing glucose control. In this review, we have summarized the clinical considerations to guide and inform clinicians providing care for people with diabetes on PD.

Making sense of glucose sensors in end-stage kidney disease: A review

Diabetes mellitus remains the leading cause of end-stage kidney disease worldwide. Inadequate glucose monitoring has been identified as one of the gaps in care for hemodialysis patients with diabetes, and lack of reliable methods to assess glycemia has contributed to uncertainty regarding the benefit of glycemic control in these individuals. Hemoglobin A1c, the standard metric to evaluate glycemic control, is inaccurate in patients with kidney failure, and does not capture the full range of glucose values for patients with diabetes. Recent advances in continuous glucose monitoring have established this technology as the new gold standard for glucose management in diabetes. Glucose fluctuations are uniquely challenging in patients dependent on intermittent hemodialysis, and lead to clinically significant glycemic variability. This review evaluates continuous glucose monitoring technology, its validity in the setting of kidney failure, and interpretation of glucose monitoring results for the nephrologist. Continuous glucose monitoring targets for patients on dialysis have yet to be established. While continuous glucose monitoring provides a more complete picture of the glycemic profile than hemoglobin A1c and can mitigate high-risk hypoglycemia and hyperglycemia in the context of the hemodialysis procedure itself, whether the technology can improve clinical outcomes merits further investigation.

The Nephrologist's Role in the Collaborative Multi-Specialist Network Taking Care of Patients with Diabetes on Maintenance Hemodialysis: An Overview

Diabetes mellitus is the leading cause of renal failure in incident dialysis patients in several countries around the world. The quality of life for patients with diabetes in maintenance hemodialysis (HD) treatment is in general poor due to disease complications. Nephrologists have to cope with all these problems because of the “total care model” and strive to improve their patients’ outcome. In this review, an updated overview of the aspects the nephrologist must face in the management of these patients is reported. The conventional marker of glycemic control, hemoglobin A1c (HbA1c), is unreliable. HD itself may be responsible for dangerous hypoglycemic events. New methods of glucose control could be used even during dialysis, such as a continuous glucose monitoring (CGM) device. The pharmacological control of diabetes is another complex topic. Because of the risk of hypoglycemia, insulin and other medications used to treat diabetes may need dose adjustment. The new class of antidiabetic drugs dipeptidyl peptidase 4 (DPP-4) inhibitors can safely be used in non-insulin-dependent end-stage renal disease (ESRD) patients. Nephrologists should take care to improve the hemodynamic tolerance to HD treatment, frequently compromised by the high level of ultrafiltration needed to counter high interdialytic weight gain. Kidney and pancreas transplantation, in selected patients with diabetes, is the best therapy and is the only approach able to free patients from both dialysis and insulin therapy.

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.

Diabetes mellitus in dialysis and renal transplantation

Diabetes mellitus is the commonest cause of end-stage kidney failure worldwide and is a proven and significant risk factor for the development of cardiovascular disease. Renal impairment has a significant impact on the physiology of glucose homeostasis as it reduces tissue sensitivity to insulin and reduces insulin clearance. Renal replacement therapy itself affects glucose control: peritoneal dialysis may induce hyperglycaemia due to glucose-rich dialysate and haemodialysis often causes hypoglycaemia due to the relatively low concentration of glucose in the dialysate. Autonomic neuropathy which is common in chronic kidney disease (CKD) and diabetes increases the risk for asymptomatic hypoglycaemia. Pharmacological options for improving glycaemic control are limited due to alterations to drug metabolism. Impaired glucose tolerance and diabetes are also common in the post-kidney-transplant setting and increase the risk of graft failure and mortality. This review seeks to summarise the literature and tackle the intricacies of glycaemic management in patients with CKD who are either on maintenance haemodialysis or have received a kidney transplant. It outlines changes to glycaemic targets, monitoring of glycaemic control, the use of oral hypoglycaemic agents, the management of severe hyperglycaemia in dialysis and kidney transplantation patients.

Hemodialysis-Related Glycemic Disarray Proven by Continuous Glucose Monitoring; Glycemic Markers and Hypoglycemia

OBJECTIVE

There is a high risk of asymptomatic hypoglycemia associated with hemodialysis (HD) using glucose-free dialysate; therefore, the inclusion of glucose in the dialysate is believed to prevent intradialytic hypoglycemia. However, the exact glycemic fluctuation profiles and frequency of asymptomatic hypoglycemia using dialysates containing >100 mg/dL glucose have not been determined.

RESEARCH DESIGN AND METHODS

We evaluated the glycemic profiles of 98 patients, 68 of whom were men, with type 2 diabetes undergoing HD (HbA_1c 6.4 ± 1.2%; glycated albumin 20.8 ± 6.8%) with a dialysate containing 100, 125, or 150 mg/dL glucose using continuous glucose monitoring.

RESULTS

Sensor glucose level (SGL) showed a sustained decrease during HD, irrespective of the dialysate glucose concentration, and reached a nadir that was lower than the dialysate glucose concentration in 49 participants (50%). Twenty-one participants (21%) presented with HD-related hypoglycemia, defined by an SGL <70 mg/dL during HD and/or between the end of HD and their next meal. All these hypoglycemic episodes were asymptomatic. Measures of glycemic variability calculated using the SGL data (SD, coefficient of variation, and range of SGL) were higher and time below range (<70 mg/dL) was lower in participants who experienced HD-related hypoglycemia than in those who did not, whereas time in range between 70 and 180 mg/dL, time above range (>180 mg/dL), HbA_1c, and glycated albumin of the two groups were similar.

CONCLUSIONS

Despite the use of dialysate containing 100-150 mg/dL glucose, patients with diabetes undergoing HD experienced HD-related hypoglycemia unawareness frequently. SGL may fall well below the dialysate glucose concentration toward the end of HD.

Management of diabetes mellitus in dialysis patients: Obstacles and challenges

BACKGROUND AND AIMS

Diabetic kidney disease (DKD) is a major health issue that is associated with an increased risk of morbidity and mortality. The treatment of DKD is challenging given changes in blood glucose homeostasis, unclear accuracy of glucose metrics, and altered kinetics of the blood glucose-lowering medications. There is uncertainty surrounding the optimal glycemic target in this population although recent epidemiologic data suggest that HbA1c ranges of 6-8%, as well as 7-9%, are associated with increased survival rates among diabetic dialysis patients. Furthermore, the treatment of diabetes in patients maintained on dialysis is challenging, and many blood glucose-lowering medications are renally metabolized and excreted hence requiring dose adjustment or avoidance in dialysis patients.

METHOD

ology: PubMed, Google Scholar, and Medline were searched for all literature discussing the management of diabetes in dialysis patients.

RESULTS

The literature was discussed under many subheadings providing the latest evidence in the treatment of diabetes in dialysis patients.

CONCLUSION

The management of diabetes in dialysis is very complex requiring a multi-disciplinary team involving endocrinologists and nephrologists to achieve targets and reduce morbidity and mortality.

Oxidized Albumin as a Mediator of Kidney Disease

Renal diseases are a global health concern, and nearly 24% of kidney disease patients are overweight or obese. Particularly, increased body mass index has been correlated with oxidative stress and urinary albumin excretion in kidney disease patients, also contributing to increased cardiovascular risk. Albumin is the main plasma protein and is able to partially cross the glomerular filtration barrier, being reabsorbed mainly by the proximal tubule through different mechanisms. However, it has been demonstrated that albumin suffers different posttranslational modifications, including oxidation, which appears to be tightly linked to kidney damage progression and is increased in obese patients. Plasma-oxidized albumin levels correlate with a decrease in estimated glomerular filtration rate and an increase in blood urea nitrogen in patients with chronic kidney disease. Moreover, oxidized albumin in kidney disease patients is independently correlated with higher plasma levels of transforming growth factor beta (TGF-β1), tumor necrosis factor (TNF-α), and interleukin (IL)-1β and IL-6. In addition, oxidized albumin exerts a direct effect on neutrophils by augmenting the levels of neutrophil gelatinase-associated lipocalin, a well-accepted biomarker for renal damage in patients and in different experimental settings. Moreover, it has been suggested that albumin oxidation occurs at early stages of chronic kidney disease, accelerating the patient requirements for dialytic treatment during disease progression. In this review, we summarize the evidence supporting the role of overweight- and obesity-induced oxidative stress as a critical factor for the progression of renal disease and cardiovascular morbimortality through albumin oxidation.

Serum glycated albumin predicts all-cause mortality in dialysis patients with diabetes mellitus: meta-analysis and systematic review of a predictive biomarker

BACKGROUND AND AIM

HbA1c, the traditional and current gold standard biomarker guiding diabetic management, has been scrutinized for low predictive value for patients with chronic kidney disease due to variables affecting erythrocyte number and turnover. Glycated albumin, the precursor to advanced glycation end products, reflects glycemic status over the preceding 2-3 week period and already outperforms HbA1c for glycemic monitoring. Our aim was to establish whether serum GA can be further used to predict mortality risk in dialysis patients with diabetes mellitus (DM) METHODS: We did systematic review of the literature in PubMed/Medline, Web of Science, Embase (Elsevier) and the Cochrane Central Register of Controlled Trials (Wiley) up to and including February 2020.

RESULTS

This meta-analysis included 25,932 dialysis patients across 12 studies with maximum follow-up of 11 years. Higher GA levels were associated with the risk of all-cause mortality in dialysis patients with DM (HR 1.02, 95% CI 1.01 to 1.03, P < 0.001) irrespective of the type of dialysis, whereas higher GA was not associated with cardiovascular mortality (HR 1.03, 95% CI 0.99 to 1.06, P = 0.15) and cardiovascular events (both fatal and non-fatal) (HR 1.03, 95% CI 0.97 to 1.09, P = 0.31) in dialysis patients with DM.

CONCLUSION

Serum glycated albumin predicts all-cause mortality risk in dialysis patients with DM. The endpoints of cardiovascular mortality and cardiovascular events trended similarly, but did not reach significance at the current sample size.

Glycated albumin and hemoglobin A1c levels and cause-specific mortality by patients' conditions among hemodialysis patients with diabetes: a 3-year nationwide cohort study

INTRODUCTION

Differences in mortality and cause-specific mortality rates according to glycated albumin (GA) and hemoglobin A1c (HbA1c) levels among dialysis patients with diabetes based on hypoglycemic agent use and malnutrition status remain unclear. Here, we examine these associations using a nationwide cohort.

RESEARCH DESIGN AND METHODS

We examined 40 417 dialysis patients with diabetes who met our inclusion criteria (female, 30.8%; mean age, 67.3±11.2 years; mean dialysis duration, 5.4±4.6 years). The Global Leadership Initiative on Malnutrition criteria were used to assess malnutrition. Adjusted HRs and 95% confidence limits were calculated for 3-year mortality after adjustment for 18 potential confounders. HRs and subdistribution HRs were used to explore cause-specific mortality.

RESULTS

We found a linear association between 3-year mortality and GA levels only in patients with GA ≥18% and not in patients with low GA levels, with a U-shaped association between HbA1c levels and the lowest morality at an HbA1c 6.0%-6.3%. This association differed based on patient conditions and hypoglycemic agent use. If patients using hypoglycemic agents were malnourished, mortality was increased with GA ≥24% and HbA1c ≥8%. In addition, patients with GA ≥22% and HbA1c ≥7.6% had significantly higher infectious or cardiovascular mortality rates. On the other hand, an inverse association was found between GA or HbA1c levels and cancer mortality. Patients with GA ≤15.8% had a higher risk of cancer mortality, especially those not using hypoglycemic agents (HR 1.63 (1.00-2.66)).

CONCLUSIONS

Target GA and HbA1c levels in dialysis patients may differ according to hypoglycemic agent use, nutritional status, and the presence of cancer. The levels may be higher in malnourished patients than in other patients, and a very low GA level in dialysis patients not taking hypoglycemic agents may be associated with a risk of cancer.

TRIAL REGISTRATION NUMBER

UMIN000018641.

When ESKD complicates the management of diabetes mellitus

Given the increased incidence and prevalence of ESKD (end-stage kidney disease) attributed to diabetes mellitus, it is important to consider the physiological and global sociodemographic factors that give rise to unique challenges in providing excellent care to this population. The individual with diabetes and ESKD faces alterations of glucose homeostasis that require close therapeutic attention, as well as the consideration of safe and effective means of maintaining glycemic control. Implementation of routine monitoring of blood glucose and thoughtful alteration of the individual's hypoglycemic drug regimen must be employed to reduce the risk of neurological, cardiovascular, and diabetes-specific complications that may arise as a result of ESKD. Titration of insulin therapy may become quite challenging, as kidney replacement therapy often significantly impacts insulin requirements. New medications have significantly improved the ability of the clinician to provide effective therapies for the management of diabetes, but have also raised an equal amount of uncertainty with respect to their safety and efficacy in the ESKD population. Additionally, the clinician must consider the challenges related to the delivery of kidney replacement therapy, and how inter-modality differences may impact glycemic control, diabetes, and ESKD-related complications, and issues surrounding dialysis vascular access creation.

Diabetes-related knowledge in diabetic haemodialysis patients: a cross-sectional study from Palestine

Background

Diabetes mellitus is the leading cause of end-stage renal disease. Monitoring and controlling normal blood sugar levels play a critical role in slowing the progression of micro- and macrovascular complications of diabetes. This study was conducted to measure glycaemic control and diabetes-related knowledge in diabetic patients on maintenance haemodialysis and to assess any relationship between these two variables.

Methods

This cross-sectional study was conducted at six dialysis centres in the north of the West Bank. Blood samples were collected to measure glycated haemoglobin (HbA1c) levels, while the Michigan Diabetic Knowledge Test (MDKT) was employed as a measure tool of diabetes-related knowledge. Patients were also asked to fill in a questionnaire in order to determine their sociodemographic characteristics. Finally, univariate analyses were used to measure the associations between the clinical and sociodemographic data, and diabetes knowledge and glycaemic control.

Results

A total of 147 haemodialysis patients with diabetes were included in this study. The mean age of the cohort was 60.12 (SD = 10.28). Males accounted for 51.7% of the cohort. The HbA1c levels (%) and MDKT scores were 6.89 ± 1.72 and 9.19 ± 1.7 (mean ± SD), respectively. 36.1% of the patients had poor glycemic control. The study showed that residency and household income were associated with diabetes knowledge (P < 0.05). However, the study did not show a significant association between diabetes-related knowledge and glycaemic control overall, nor did it show a significant association between the clinical and sociodemographic factors and glycaemic control (P > 0.05).

Conclusions

This study showed that patients living in refugee camps as well as those with low income had low diabetes-related knowledge and needed extra care. This study also revealed that a relatively high proportion of diabetic patients on maintenance haemodialysis suffered from poor glycemic control. Here, we recommend to put greater emphasis on better diabetes-related knowledge as a means to achieve better diabetes care with improved glycemic control for all haemodialysis patients

Glycated albumin versus hemoglobin A1c and mortality in diabetic hemodialysis patients: a cohort study

Background

For glycemic control in diabetic patients on dialysis it was unclear what level of glycated albumin (GA) was associated with the lowest mortality and GA's utility. Accordingly, we examined the difference in association between GA and hemoglobin A1c (HbA1c) with 1-year mortality in a cohort of the Japanese Society for Dialysis Therapy.

Methods

We examined 84 282 patients with prevalent diabetes who were on maintenance hemodialysis (HD) (female 30.3%; mean age 67.3 ± 11.2 years; mean dialysis vintage 6.4 ± 4.5 years). Of them, 22 441 had both GA and HbA1c. We followed these for a year, 2013-14, using Cox regression to calculate adjusted hazard ratios (HRs) and 95% confidence limits for 1-year mortality after adjusting for potential confounders such as baseline age, sex, smoking and diabetes type.

Results

One-year mortality was lowest in diabetic HD patients who had GA levels of 15.6-18.2% and HbA1c levels of 5.8-6.3%. The associations were linear or J-shaped for GA and U-shaped for HbA1c. Adjusted HRs were significantly higher in patients with GA <12.5% and GA ≥22.9%. This trend flattened in elderly patients, those with higher hemoglobin or those with prior cardiovascular disease. In addition, the C-statistics, Harrell's C and category-free net reclassification improvement to predict 1-year mortality were better when GA was added to the model than when HbA1c was added.

Conclusions

There was a linear or J-shaped association between GA and 1-year mortality, with the lowest mortality at GA 15.6-18.2%. Furthermore, our analyses suggest the potential superiority of GA over HbA1c in predicting mortality.

Glycemic control and survival in peritoneal dialysis patients with diabetes: A 2-year nationwide cohort study

For glycemic control in patients with diabetes on peritoneal dialysis (PD), the level of glycated albumin (GA) associated with mortality is unclear. Accordingly, we examined the difference in the association of GA and glycated hemoglobin (HbA1c) with 2-year mortality in a Japanese Society for Dialysis Therapy cohort. We examined 1601 patients with prevalent diabetes who were on PD. Of these, 1282 had HbA1c (HbA1c cohort) and 725 had GA (GA cohort) measured. We followed them for 2 years from 2013 to 2015 and used Cox regression to calculate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for 2-year mortality after adjusting for potential confounders in each cohort. No significant association was found between HbA1c levels and all-cause death HRs before and after adjustment for confounders in the HbA1c cohort. In contrast, the adjusted all-cause death HRs and 95% CIs for GAs < 12.0%, 12.0–13.9%, 16.0–17.9%, 18.0–19.9%, 20.0–21.9%, and ≥22.0%, compared with 14.0–15.9% (reference), were 1.56 (0.32–7.45), 1.24 (0.32–4.83), 1.32 (0.36–4.77), 2.02 (0.54–7.53), 4.36 (1.10–17.0), and 4.10 (1.20–14.0), respectively. In the GA cohort, GA ≥ 20.0% was significantly associated with a higher death HR compared with the reference GA. Thus, GA ≥ 20.0% appears to be associated with a decrease in survival in diabetic patients on PD. There were no associations between HbA1c levels and 2-year mortality in PD patients.

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.

The effect of dulaglutide on body composition in type 2 diabetes mellitus patients on hemodialysis

AIMS

To evaluate the effect of dulaglutide on body composition in type 2 diabetes mellitus (T2DM) patients undergoing hemodialysis (HD).

METHODS

Twenty-one T2DM patients on HD, who had been treated with insulin and newly added teneligliptin (N = 10) or dulaglutide (N = 11), were enrolled. Body composition changes, such as fat mass (FM) and skeletal muscle mass (SMM), glycated albumin (GA), and insulin doses were compared before and after six months of treatment with teneligliptin or dulaglutide.

RESULTS

The percentage changes of GA and insulin doses were comparable between the teneliglipin and dulaglutide groups. Conversely, although FM and SMM did not change in the teneligliptin group (from 15.7 kg to 14.1 kg, P = 0.63 and 18.6 kg to 18.9 kg, P = 0.16, respectively), those in the dulaglutide group significantly decreased (from 21.9 kg to 18.9 kg, P = 0.037 and 21.0 kg to 20.2 kg, P = 0.011, respectively).

CONCLUSIONS

Six months of dulaglutide treatment significantly reduced not only FM but also SMM, although changes in GA and insulin doses were comparable with those in the teneligliptin group. Dulaglutide may have the effect of promoting sarcopenia; therefore, it may be carefully used in T2DM patients on HD.

Usefulness of glycated albumin as a biomarker for glucose control and prognostic factor in chronic kidney disease patients on dialysis (CKD-G5D)

In chronic kidney disease patients on dialysis (CKD-G5D) accurate assessment of glycemic control is vital to improve their outcome and survival. The best glycemic marker for glucose control in these patients is still debated because several clinical and pharmacological factors may affect the ability of the available biomarkers to reflect the patient's glycemic status properly. This review discusses the role of glycated albumin (GA) both as a biomarker for glucose control and as a prognostic factor in CKD-G5D; it also looks at the pros and cons of GA in comparison to the other markers and its usefulness in hemodialysis and peritoneal dialysis.

Glycated albumin in chronic kidney disease: Pathophysiologic connections

Nephropathy in diabetes patients is the most common etiology of end-stage kidney disease (ESKD). Strict glycemic control reduces the development and progression of diabetes-related complications, and there is evidence that improved metabolic control improves outcomes in subjects having diabetes mellitus with advanced chronic kidney disease (CKD). Glycemic control in people with kidney disease is complex. Changes in glucose and insulin homoeostasis may occur as a consequence of loss of kidney function and dialysis. The reliability of measures of long-term glycemic control is affected by CKD and the accuracy of glycated haemoglobin (HbA1c) in the setting of CKD and ESKD is questioned. Despite the altered character of diabetes in CKD, current guidelines for diabetes management are not specifically adjusted for this patient group. The validity of indicators of long-term glycemic control has been the focus of increased recent research. This review discusses the current understanding of commonly used indicators of metabolic control (HbA1c, fructosamine, glycated albumin) in the setting of advanced CKD.

Performance of non-traditional hyperglycemia biomarkers by chronic kidney disease status in older adults with diabetes: Results from the Atherosclerosis Risk in Communities Study

BACKGROUND

In people with chronic kidney disease (CKD), HbA1c may be a problematic measure of glycemic control. Glycated albumin and fructosamine have been proposed as better markers of hyperglycemia in CKD. In the present study we investigated associations of HbA1c, glycated albumin, and fructosamine with fasting glucose by CKD categories.

METHODS

A cross-sectional analysis was performed of 1665 Atherosclerosis Risk in Communities Study participants with diagnosed diabetes aged ≥65 years. Spearman's rank correlations (r) were compared and Deming regression was used to obtain root mean square errors (RMSEs) for the associations across CKD categories defined using estimated glomerular filtration rate and urine albumin:creatinine ratio.

RESULTS

Correlations of HbA1c, glycated albumin, and fructosamine with fasting glucose were lowest in people with severe CKD (HbA1c r = 0.52, RMSE = 0.91; glycated albumin r = 0.39, RMSE = 1.89; fructosamine r = 0.41, RMSE = 1.87) and very severe CKD (r = 0.48 and RMSE = 1.01 for HbA1c; r = 0.36 and RMSE = 2.14 for glycated albumin; r = 0.36 and RMSE = 2.22 for fructosamine). Associations of glycated albumin and fructosamine with HbA1c were relatively similar across CKD categories.

CONCLUSIONS

In older adults with severe or very severe CKD, HbA1c, glycated albumin, and fructosamine were not highly correlated with fasting glucose. The results suggest there may be no particular advantage of glycated albumin or fructosamine over HbA1c for monitoring glycemic control in CKD.

Hypoglycemic Coma in a Hemodialysis Patient Receiving Blood Glucose-Lowering Therapy With the Single Agent Teneligliptin

Blood glucose management in patients undergoing dialysis is clinically challenging. In this population, most conventional oral hypoglycemic agents are contraindicated, especially from the perspective of pharmacokinetics. Dipeptidyl peptidase-4 inhibitors exert unique pharmacologic actions via glucose-dependent mechanism and have an excellent tolerability profile with a very low risk of hypoglycemia. Furthermore, the literature reports that some dipeptidyl peptidase-4 inhibitors such as teneligliptin can be administered at the usual dose, regardless of a patient's level of renal impairment. In this article, we report a case of hypoglycemic coma with a blood glucose level of 23 mg/dL. The patient became fully conscious shortly after receiving a glucose injection; however, severe hypoglycemia recurred for approximately 1.5 days. It eventually disappeared on the discontinuation of teneligliptin, which was the only antidiabetic agent that he had received. The present case may provide deep insights into promoting the safe use of hypoglycemic agents in patients undergoing dialysis.

Managing Diabetes and Cardiovascular Risk in Chronic Kidney Disease Patients

We discuss mechanisms of increased cardiovascular disease (CVD) in patients with chronic kidney disease (CKD) and strategies for managing cardiovascular (CV) risk in these patients. Our focus was mainly on decreasing CV events and progression of microvascular complications by reducing levels of glucose and lipids. We searched PubMed with no limit on the date of the article. All articles were discussed among all authors. We chose pertinent articles, and searched their references in turn for additional relevant publications.

Improved glycemic control with once-weekly dulaglutide in addition to insulin therapy in type 2 diabetes mellitus patients on hemodialysis evaluated by continuous glucose monitoring

AIMS

To evaluate the efficacy and safety of adding once-weekly dulaglutide to insulin therapy in type 2 diabetes mellitus (T2DM) patients on hemodialysis.

METHODS

Fifteen insulin-treated T2DM patients on hemodialysis were enrolled. Continuous glucose monitoring was performed before (1st hospitalization) and after the fifth dulaglutide administration (2nd hospitalization). The insulin dose was reduced after the first administration of dulaglutide (1st hospitalization day 6). Parameters of glycemic control were compared on 1st hospitalization days 4-5, 2nd hospitalization days 3-4, and days 6-7.

RESULTS

The median total daily insulin dose was reduced significantly from 12 (12-25) to 0 (0-12) U (p < 0.0001) after treatment with dulaglutide. Mean glucose level on 2nd hospitalization days 3-4 significantly decreased and that on days 6-7 tended to decrease compared with that on 1st hospitalization days 4-5 (median, 8.2 to 6.7 mmol/L, P = 0.006 and 8.2 to 6.9 mmol/L, P = 0.053, respectively). %CV of glucose levels decreased significantly after dulaglutide administration (28.1 to 19.8, P = 0.003 and 28.1 to 21.0, P = 0.019). However, the incidence of hypoglycemia remained unchanged.

CONCLUSIONS

Dulaglutide may improve glycemic control and excursion and allow total daily insulin to be reduced without increasing the risk of hypoglycemia in T2DM patients on hemodialysis.

Long-Term Survivor Characteristics in Hemodialysis Patients with Type 2 Diabetes

BACKGROUND

Data concerning long-term mortality predictors among large, purely diabetic hemodialysis collectives are scarce.

METHODS

We used data from a multicenter, prospective, randomized trial among 1,255 hemodialysis patients with type 2 diabetes mellitus (T2DM) and its observational follow-up study. The association of 10 baseline candidate variables with mortality was assessed by Cox proportional hazards regression.

RESULTS

Overall, 103 participants survived the median follow-up of 11.5 years. Significant predictors of mortality were age (hazard ratio [HR] 1.03, 95% CI 1.02-1.04), cardiovascular (HR 1.42, 95% CI 1.25-1.62) and peripheral vascular disease (HR 1.55, 95% CI 1.36-1.76), higher hemoglobin A1c (HbA1c; HR 1.08, 95% CI 1.03-1.14), and loss of self-dependency (HR 1.20, 95% CI 1.03-1.39). Higher albumin (HR 0.72, 95% CI 0.59-0.89) and body mass index (BMI; HR 0.98, 95% CI 0.96-0.99) had protective associations. There was no significant association with sex, diabetes duration, and cerebrovascular diseases. Subgroup analyses by age and diabetes duration showed stronger associations of cardiovascular disease, HbA1c, albumin, BMI, and loss of self-dependency in younger patients and/or shorter diabetes duration. Loss of self-dependency and energy resources (albumin, BMI) increased mortality more severely in women, whilst the impact of cardiovascular and peripheral vascular diseases was more pronounced in men.

CONCLUSION

Long-term mortality risk in patients with T2DM on hemodialysis was associated with higher age, vascular diseases, HbA1c, loss of self-dependency, and low energy resources. Interestingly, it does not vary between sexes. Further individualized prognosis estimation and therapy should strongly depend on age, diabetes duration, and gender.

Comparison of Glycemic Markers in Chronic Hemodialysis Using Continuous Glucose Monitoring

BACKGROUND

Glycated hemoglobin A1c (HbA1c) among diabetic hemodialysis patients continues to be the standard of care, although its limitations are well recognized. This study evaluated glycated albumin (GA) and glycated serum protein (GSP) as alternatives to HbA1c in detecting glycemic control among diabetic hemodialysis patients using continuous-glucose-monitoring (CGM)-derived glucose as reference standard.

METHODS

A CGM system (iPRO) was applied for 7 days in 37 diabetic hemodialysis patients to determine glycemic control. The accuracy of GA and GSP versus HbA1c in detecting a 7-day average glucose ≥184 mg/dL was evaluated via receiver-operating-characteristic (ROC) analysis.

RESULTS

CGM-derived glucose exhibited strong correlation (r = 0.970, p < 0.001) and acceptable agreement with corresponding capillary glucose measurements obtained by the patients themselves in 1,169 time-points over the 7-day-long CGM. The area under ROC curve (AUC) for GA, GSP, and HbA1c to detect poor glycemic control was 0.976 (0.862-1.000), 0.682 (0.502-0.862), and 0.776 (0.629-0.923) respectively. GA levels >20.3% had 90.9% sensitivity and 96.1% specificity in detecting a 7-day average glucose ≥184 mg/dL. The AUC for GA was significantly higher than the AUC for GSP (difference between areas: 0.294, p < 0.001) and the AUC for HbA1c (difference between areas: 0.199, p < 0.01).

CONCLUSION

Among diabetic hemodialysis patients, GA is a stronger indicator of poor glycemic control assessed with 7-day-long CGM when compared to GSP and HbA1c.

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.

Glycosylation Gap in Patients with Diabetes with Chronic Kidney Disease and Healthy Participants: A Comparative Study

AIM

The aim of this study it to determine the level of glycosylation gap in patients with type 2 diabetes and its relation with kidney dysfunction.

MATERIALS AND METHODS

In this study, 150 individuals were enrolled (aged 20-75 year) and divided into three groups. Group 1 included 50 nondiabetic individuals who served as control. Group 2 included 50 patients with type 2 diabetes without chronic kidney disease (CKD), and in Group 3, there were 50 patients with type 2 diabetes with CKD. Glycated hemoglobin (HbA1c) and fructosamine (FA) were measured in all groups to determine the glycosylation gap (GG), predicted HbA1c, and mean blood glucose (MBG). GG is defined as the difference between measured HbA1c and HbA1c predicted from FA based on the population regression of HbA1c on FA. The variables were compared by correlation analysis.

RESULTS

Serum creatinine level was significantly high in patients with CKD (1.93 ± 0.99) as compared to patients with diabetes and control (0.891 ± 0.16; 0.912 ± 0.1), respectively. The study demonstrated a significant elevation in serum FA, measured HbA1c and predicted HbA1c, MBG in patients with diabetes with CKD as compared with those of without CKD, and controls. GG was found in healthy control (0.51 ± 0.78), patients with type 2 diabetes without CKD (0.62 ± 0.45), and patients with diabetes with CKD (1.0 ± 0.91), respectively.

CONCLUSION

It is concluded that GG may be a useful clinical research tool for evaluating pathological source of variation in diabetes complications such as kidney disease.

PATHOPHYSIOLOGY AND MANAGEMENT OF HYPOGLYCEMIAIN END-STAGE RENAL DISEASE PATIENTS: A REVIEW

OBJECTIVE

This review focuses on hypoglycemia in patients with end-stage renal disease (ESRD). It discusses the pathophysiology of glucose metabolism in the kidney, the impact of dialysis on glucose and insulin metabolism, and the challenges of glucose monitoring in ESRD. The clinical relevance of these changes is reviewed in relation to altered blood glucose targets and modification of antidiabetes therapy to prevent hypoglycemia. Based on current data and guidelines, recommendations for the outpatient and inpatient setting are provided for diabetes management in ESRD.

METHODS

PubMed, OVID, and Google Scholar were searched to identify related articles through May 2016 using the following keywords: "glucose metabolism," "kidney," "diabetes," "hypoglycemia," "ESRD," and "insulin" in various combinations for this review.

RESULTS

In ESRD, a combination of impaired insulin clearance, changes in glucose metabolism, and the dialysis process make patients vulnerable to low blood glucose levels. Hypoglycemia accounts for up to 3.6% of all ESRD-related admissions. At admission or during hospitalization, hypoglycemia in ESRD has a poor prognosis, with mortality rates reported at 30%. Several guidelines suggest a modified hemoglobin A1c (A1c) goal of 7 to 8.5% (53 to 69 mmol/mol) and an average blood glucose goal of 150 to 200 mg/dL. Noninsulin antidiabetes agents like dipeptidyl peptidase 4 inhibitors, repaglinide, and glipizide in appropriate doses and reduction of insulin doses up to 50% may help decrease hypoglycemia.

CONCLUSION

Patients with ESRD are at high risk for hypoglycemia. Increased awareness by providers regarding these risks and appropriate diabetes regimen adjustments can help minimize hypoglycemic events.

ABBREVIATIONS

ADA = antidiabetes agent BG = blood glucose CKD = chronic kidney disease DPP-4 = dipeptidyl peptidase 4 eGFR = estimated glomerular filtration rate ESRD = end-stage renal disease GFR = glomerular filtration rate HD = hemodialysis NPH = neutral protamine Hagedorn PD = peritoneal dialysis SA = short acting SU = sulfonylurea.

Efficacy and safety of teneligliptin in addition to insulin therapy in type 2 diabetes mellitus patients on hemodialysis evaluated by continuous glucose monitoring

AIMS

Appropriate glycemic control without hypoglycemia is important in patients with type 2 diabetes on hemodialysis. Teneligliptin, a novel dipeptidyl peptidase-4 inhibitor, can be used without dose adjustment for these patients. Using continuous glucose monitoring (CGM), we evaluated the efficacy and safety of adding teneligliptin to insulin therapy.

METHODS

Twenty-one type 2 diabetes mellitus patients on hemodialysis treated with insulin were enrolled. After the adjustment of insulin dose, their blood glucose level was monitored by CGM. Insulin dose was reduced after teneligliptin administration.

RESULTS

The median total daily insulin dose significantly reduced from 18 (9-24)U to 6 (0-14)U (p<0.0001). Maximum, mean, and standard deviation of blood glucose level on the hemodialysis and non-hemodialysis days did not change after teneligliptin administration. However, minimum blood glucose level was significantly elevated on the hemodialysis day after teneligliptin administration (from 3.9±1.0mmol/L to 4.4±0.9mmol/L, p=0.040). The incidence of asymptomatic hypoglycemia on the hemodialysis day detected by CGM significantly decreased from 38.1% to 19.0% (p=0.049).

CONCLUSIONS

Teneligliptin may contribute toward reducing the total daily insulin dose and preventing hypoglycemic events on the hemodialysis day in type 2 diabetes mellitus patients.

Distinct biomarker roles for HbA1c and glycated albumin in patients with type 2 diabetes on hemodialysis

AIMS

HbA_1c and glycated albumin (GA) are used to monitor glycemia, but their accuracy to represent glycemic profiles in hemodialysis remains controversial.

METHODS

Continuous glucose monitoring in 97 patients with type 2 diabetes (41 on hemodialysis [HD] and 56 without nephropathy) was analyzed to evaluate whether HbA_1c and/or GA serve as appropriate glycemic profile markers.

RESULTS

The average glucose significantly correlated with HbA_1c in both HD group and group without nephropathy (r=0.59, P<0.0001; r=0.40, P<0.005). The slopes of linear regression lines were statistically indistinguishable (F=0.30, P=0.744), while the y-intercepts were significantly different (F=57.86, P<0.0001). GA showed strong correlation with the glycemic standard deviation (r=0.68, P<0.0001), and with the average glucose (r=0.42, P<0.001). Least square analysis revealed that only HbA_1c, but not GA, was significantly associated with the average glucose (F=10.20, P<0.0005; F=0.38, P=0.5427), while only GA was significantly associated with the glycemic variability in HD group.

CONCLUSIONS

In HD participants, HbA_1c correlates with the average glucose more than GA, but underestimates it, and a correction formula of HbA1c can be developed as an appreciable marker. GA value itself reflects the average glucose, but less accurately than HbA_1c, while it could serve as an indicator for hyperglycemia/hypoglycemia excursion.

High Glycated Albumin and Mortality in Persons with Diabetes Mellitus on Hemodialysis

BACKGROUND

Monitoring of glycemic control with hemoglobin A_1c (A1c) in hemodialysis patients may be compromised by anemia and erythropoietin therapy. Glycated albumin (GA) is an alternative measure of glycemic control but is not commonly used because of insufficient evidence of association to clinical outcomes. We tested whether GA measurements were associated with mortality in hemodialysis patients with diabetes mellitus.

METHODS

The German Diabetes and Dialysis Study (4D) investigated effects of atorvastatin on survival in 1255 patients with diabetes mellitus receiving hemodialysis. We measured GA during months 0, 6, and 12. Cox proportional hazards analysis was used to measure associations between GA and A1c and all-cause mortality.

RESULTS

Patients with high baseline GA (fourth quartile) had a 42% higher 4-year mortality compared to those in the first quartile (HR 1.42; 95% CI, 1.09-1.85, P = 0.009). Repeated measurements of GA during year one also demonstrated that individuals in the top quartile for GA (analyzed as a time-varying covariate) had a 39% higher 4-year mortality (HR 1.39; 95% CI, 1.05-1.85, P = 0.022). The associations between high A1c and mortality using similar analyses were less consistent; mortality in individuals with baseline A1c values in the 3rd quartile was increased compared to 1st quartile (HR 1.36; 95% CI, 1.04-1.77, P = 0.023), but risk was not significantly increased in the 2nd or 4th quartiles, and there was a less consistent association between time-varying A1c values and mortality.

CONCLUSIONS

High GA measurements are consistently associated with increased mortality in patients with diabetes mellitus on hemodialysis.

Determinant Effects of Average Fasting Plasma Glucose on Mortality in Diabetic End-Stage Renal Disease Patients on Maintenance Hemodialysis

Introduction

Diabetic kidney disease is an increasingly frequent cause of end-stage renal disease. However, mixed results were shown between glycated hemoglobin and mortality.

Methods

We used the average fasting plasma glucose (FPG) levels to predict mortality rates in long-term hemodialysis patients. We enrolled 46,332 hemodialysis patients with diabetes mellitus, who were registered in the Taiwan Renal Registry Data System between January 2005 and December 2012. The patients were stratified based on the quartiles of average FPG levels measured for the first (1-year FPG) and third years (3-year FPG) of hemodialysis. Survival analysis was conducted via multivariable Cox regression.

Results

After the first year of hemodialysis, the mean FPG levels were 103.5 ± 14.5, 144.7 ± 11.5, 189.6 ± 15.2, and 280.8 ± 1.2 mg/dl for the first, second, third, and fourth quartile, respectively. The Kaplan-Meier curve showed an incremental reduction in the survival as FPG levels increased (P < 0.0001). In the Cox regression model, the adjusted hazard ratios were 1.15 (95% CI: 1.10–1.20), 1.30 (95% CI: 1.25–1.36), and 1.45 (95% CI: 1.39–1.51) for the pairwise comparisons between the first quartile and the second, third, and fourth quartile, respectively. Similar trends were observed by 3-year FPG. Patients whose FPG levels increased had a 22% increased risk (95% CI: 1.16–1.29) for all-cause mortality compared with patients whose FPG levels decreased.

Discussion

Our results suggest that the average FPG levels are useful predictors of all-cause mortality in dialysis patients. In addition, an increasing trend in average FPG levels indicates poor survival.

Efficacy of different dipeptidyl peptidase-4 (DPP-4) inhibitors on metabolic parameters in patients with type 2 diabetes undergoing dialysis

Hyperglycemia is associated with increased mortality and morbidity in patients with type 2 diabetes mellitus (T2DM) who are undergoing dialysis. Although dipeptidyl peptidase-4 (DPP-4) inhibitors have been widely used in end-stage renal disease (ESRD) patients with T2DM, there are few studies on their efficacy in this population. We studied the effect of 3 different DPP-4 inhibitors on metabolic parameters in ESRD patients with T2DM.Two hundred ESRD patients with T2DM who were treated with DPP-4 inhibitors (sitagliptin, vildagliptin, or linagliptin) were enrolled and analyzed retrospectively. The changes in glycated hemoglobin (HbA1c), fasting plasma glucose, and lipid profiles were assessed before and after 3 months of treatment with DPP-4 inhibitors. Subgroup analysis was done for each hemodialysis (HD) and peritoneal dialysis (PD) group.There was no significant difference in the decrease in the HbA1c level among sitagliptin, vildagliptin, and linagliptin treatment groups (-0.74 ± 1.57, -0.39 ± 1.45, and -0.08 ± 1.40, respectively, P = 0.076). The changes in fasting blood glucose and lipid profiles were also not significantly different. In HD patients (n = 115), there was no difference in the HbA1c level among the 3 groups. In contrast, in PD patients (n = 85), HbA1c was reduced more after 3 months of treatment with sitagliptin compared with vildagliptin and linagliptin (-1.58 ± 0.95, -0.46 ± 0.98, -0.04 ± 1.22, respectively, P = 0.001).There was no significant difference in the glucose-lowering effect between the different DPP-4 inhibitors tested in ESRD patients. In PD patients, sitagliptin tends to lower the HbA1c level more than the other inhibitors. The glucose-lowering efficacy of the 3 DPP-4 inhibitors was comparable.

Serum albumin-adjusted glycated albumin is a better predictor of mortality in diabetic patients with end-stage renal disease on hemodialysis

AIMS

Glycated albumin (GA) is a marker for monitoring glycemic control in diabetic patients with end-stage renal disease (ESRD). We evaluated whether serum albumin-adjusted GA (adjusted GA) could predict mortality in diabetic patients with ESRD on hemodialysis.

METHODS

Seventy-eight patients with type 2 diabetes treated with regular hemodialysis were enrolled and followed up for 5-years. The adjusted GA was calculated from the regression formula and mean GA. The cut-off values for GA and adjusted GA that predicted mortality risk were determined using receiver operating characteristic curve analysis.

RESULTS

During the follow-up period (median: 36months), 15 patients died. In the Kaplan-Meier analysis, there were no significant differences in the 5-year cumulative survival rate (58.3% [GA ≥19.8%] vs. 88.6% [GA <19.8%], P=0.075). Conversely, this rate was significantly higher in patients with adjusted GA <21.2% than adjusted GA ≥21.2% (86.4 vs. 49.5%, P=0.0068). After adjustment for other confounders, adjusted GA ≥21.2% was an independent predictor for mortality (hazard ratio 3.76, 95% confidence interval 1.12-17.44, P=0.031), but GA ≥19.8% was not (hazard ratio 2.63, 95% confidence interval 0.65-17.69, P=0.19).

CONCLUSIONS

Adjusted GA is a better predictor of mortality than GA in diabetic patients with ESRD on hemodialysis.

Changes in antidiabetic prescription patterns and indicators of diabetic control among 200,000 patients over 13 years at a single institution in Japan

BACKGROUND

We examined the long-term changes in the management of diabetes at a single institution in Japan.

METHODS

Two repeated cross-sectional studies and a retrospective cohort study were conducted among patients who visited our institution between 2001 and 2013. We examined the changes in glycated hemoglobin (HbA1c) and glycated albumin levels, the prescription frequencies, and the daily doses of each antidiabetic agent among patients treated regularly for diabetes during the 13-year study period. The trends in control and treatment parameters were analyzed using Spearman's rank correlation coefficient.

RESULTS

In the first repeated cross-sectional studies, 200,298 patients had their glucose metabolism indicators measured, and diabetologists prescribed medications to 193, 445 patients. Of these, 170 patients were included in the retrospective cohort study. The patients' diabetic control tended to improve over the study period. The mean HbA1c level improved from 7.9 to 7.6% (from 63 to 60 mmol/mol) (rs = -0.11, p < 0.01) in the cross-sectional study, corresponding to a change from 8.2 to 7.7% (from 66 to 61 mmol/mol) (rs = -0.22, p < 0.01) in the retrospective study. The mean GA level improved from 22.7 to 20.7% (rs = -0.13, p < 0.01) in the cross-sectional study and from 23.5 to 21.5% (rs = -0.14, p < 0.01) in the retrospective study. Over the study period, prescription frequencies and daily doses of antidiabetic agents changed as treatment guidelines were altered.

CONCLUSIONS

The present study revealed a tendency toward long-term improvements in diabetic control, with changes in the prescription patterns consistent with research and guideline evidence.

Glycated albumin is a more accurate glycaemic indicator than haemoglobin A1c in diabetic patients with pre-dialysis chronic kidney disease

AIM

Glycated albumin (GA) has been reported to be a more reliable glycaemic indicator than haemoglobin A_1c (HbA_1c ) in patients with diabetes on dialysis. However, the significance of these assays has been less evaluated in patients with diabetes and pre-dialysis chronic kidney disease (CKD).

METHODS

GA, HbA_1c and fasting serum glucose were measured simultaneously in 146 patients with diabetes. Based on estimated glomerular filtration rate (eGFR), the subjects were categorized into a pre-dialysis CKD group (eGFR < 60 mL/min per 1.73 m² , n = 97) and a non-CKD group (eGFR ≥ 60 mL/min per 1.73 m² , n = 49).

RESULTS

The glucose/HbA_1c and GA/HbA_1c ratios were significantly higher in the CKD group than those in the non-CKD group. The glucose/GA ratio did not differ significantly between the two groups. In the pre-dialysis CKD group, eGFR was negatively correlated with the glucose/HbA_1c ratio (r = -0.343, P = 0.001) and the GA/HbA_1c ratio (r = -0.499, P < 0.001). However, no significant correlation was detected between eGFR and the glucose/GA ratio. In the non-CKD group, eGFR was not correlated with the glucose/HbA_1c ratio, the glucose/GA ratio, or the GA/HbA_1c ratio. A multivariate regression analysis showed that eGFR had a significant impact on HbA_1c but no effect on GA in the pre-dialysis CKD group (β = 0.210, P = 0.005). In the non-CKD group, eGFR did not affect HbA_1c or GA.

CONCLUSION

Our results show that HbA_1c significantly underestimated glycaemic control, whereas GA more accurately reflected glycaemic control in diabetic patients with pre-dialysis CKD.

Serum albumin-adjusted glycated albumin reflects glycemic excursion in diabetic patients with severe chronic kidney disease not treated with dialysis

OBJECTIVE

Diabetic patients with severe chronic kidney disease (CKD) not treated with dialysis falsely show low levels of HbA1c and GA due to renal anemia and proteinuria, respectively. Recently, we reported that serum albumin-adjusted GA (adjGA) accurately reflects mean plasma glucose (PG) in these patients. It is considered that GA reflects not only mean PG but also glycemic excursion; therefore, in the present study we investigated whether adjGA reflects glycemic excursion in these patients.

METHODS

Thirty type 2 diabetic patients with severe CKD not treated with dialysis were enrolled in the present study. PG was monitored by seven times a day, and indicators of glycemic excursion [SD, max PG, ΔPG, M value, J index, and mean amplitude of glucose excursion (MAGE)] were calculated. The correlations between HbA1c, GA or adjGA and indicators of glycemic excursion were investigated.

RESULTS

HbA1c showed no significant correlation with indicators of glycemic excursion. GA was significantly correlated with them except for ΔPG. adjGA was significantly and strongly associated with them except for MAGE. GA, but not adjGA, showed a significant positive correlation with serum albumin.

CONCLUSION

adjGA was not influenced by serum albumin and showed a significant correlation with indicators of glycemic excursion in diabetic patients with severe CKD not treated with dialysis. These results suggest that adjGA could be useful for indicating glycemic control in diabetic patients with severe CKD not treated with dialysis.

Diabetes therapies in hemodialysis patients: Dipeptidase-4 inhibitors

Although several previous studies have been published on the effects of dipeptidase-4 (DPP-4) inhibitors in diabetic hemodialysis (HD) patients, the findings have yet to be reviewed comprehensively. Eyesight failure caused by diabetic retinopathy and aging-related dementia make multiple daily insulin injections difficult for HD patients. Therefore, we reviewed the effects of DPP-4 inhibitors with a focus on oral antidiabetic drugs as a new treatment strategy in HD patients with diabetes. The following 7 DPP-4 inhibitors are available worldwide: sitagliptin, vildagliptin, alogliptin, linagliptin, teneligliptin, anagliptin, and saxagliptin. All of these are administered once daily with dose adjustments in HD patients. Four types of oral antidiabetic drugs can be administered for combination oral therapy with DPP-4 inhibitors, including sulfonylureas, meglitinide, thiazolidinediones, and alpha-glucosidase inhibitor. Nine studies examined the antidiabetic effects in HD patients. Treatments decreased hemoglobin A1c and glycated albumin levels by 0.3% to 1.3% and 1.7% to 4.9%, respectively. The efficacy of DPP-4 inhibitor treatment is high among HD patients, and no patients exhibited significant severe adverse effects such as hypoglycemia and liver dysfunction. DPP-4 inhibitors are key drugs in new treatment strategies for HD patients with diabetes and with limited choices for diabetes treatment.

Glycated Hemoglobin Level and Mortality in a Nondiabetic Population with CKD

BACKGROUND AND OBJECTIVES

Glycated hemoglobin (HbA1c) is used to diagnose diabetes mellitus (DM) and guide its management. The association between higher HbA1c and progression to ESRD and mortality has been demonstrated in populations with DM. This study examined the association between HbA1c and these end points in a population with CKD and without DM.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

In the hospital-based NephroTest cohort study, measured GFR (mGFR) was taken by (51)Cr-EDTA renal clearance and HbA1c in 1165 adults with nondialysis CKD stages 1-5 and without DM between January 2000 and December 2010. The median follow-up was 3.48 years (interquartile range, 1.94-5.82) for the competing events of ESRD and pre-ESRD mortality. Time-fixed and time-dependent Cox models were used to estimate hazard ratios (HRs) for ESRD and mortality according to HbA1c, treated continuously or in tertiles.

RESULTS

At inclusion, the mean mGFR was 42.2±19.9 ml/min per 1.73 m(2), and the mean HbA1c value was 5.5%±0.5%. During follow-up, 109 patients died, and 162 patients reached ESRD. Pre-ESRD mortality was significantly associated with HbA1c treated continuously: for every 1% higher HbA1c, the crude HR was 2.16 (95% confidence interval [95% CI], 1.27 to 3.68), and it was 1.85 (95% CI, 1.05 to 3.24) after adjustment for mGFR and other risk factors of death. After excluding incident diabetes over time, the updated mean of HbA1c remained significantly associated with higher mortality risk: adjusted HR for the highest (5.7%-6.4%) versus the lowest tertile (<5.3%) was 2.62 (95% CI, 1.16 to 5.91). There was no association with ESRD risk after adjustment for risk factors of CKD progression.

CONCLUSIONS

In a CKD cohort, HbA1c values in the prediabetes range are associated with mortality. Such values should be therefore included among the risk factors for negative outcomes in CKD populations.

Impact of carbamylation on three different methods, HPLC, capillary electrophoresis and TINIA of measuring HbA1c levels in patients with kidney disease

AIMS

Aim of this study was to investigate whether established IFCC traceable routine measurements of HbA1c levels in patients with kidney diseases result in comparable and valid results. Additionally, the influence of carbamylation as a marker of uremia on the measurement methods was assessed.

METHODS

We compared three different measurement methods (high-performance liquid chromatography (HPLC), capillary electrophoresis and turbidimetric inhibition immunoassay (TINIA)) based on 407 nephrology samples for HbA1c determination with specific analysis of the threshold areas where different HbA1c measurements could result in different diagnoses (diabetes mellitus vs prediabetes and prediabetes vs non-diabetes). Indirectly, a potential effect of carbamylated hemoglobin was assessed based on determination of BUN levels in serum.

RESULTS

In nephrological samples, we were able to show that three different measurement methods provide similar results regarding HbA1c in routine diagnostics. Our results show that with BUN concentrations <80 mg/dl and ≥80 mg/dl, similar HbA1c levels were determined, independent of measurement method.

CONCLUSION/DISCUSSION

While routine measurements follow IFCC standards, many interfering factors remain which can influence HbA1c determination, e.g. carbamylation of proteins. As kidney disease is the most common complication in patients with diabetes mellitus, interference in the measurement of HbA1c due to carbamylated proteins as markers of uremia must be recognized and if necessary corrected. We found not only a weak influence of carbamylation on all methods of HbA1c determination, but also that, in nephrological samples, the three different measurement methods provided similar results regarding HbA1c in routine diagnostics.

The Benefit of a Glucose-Sparing PD Therapy on Glycemic Control Measured by Serum Fructosamine in Diabetic Patients in a Randomized, Controlled Trial (IMPENDIA)

BACKGROUND/AIMS

Poor glycemic control can lead to increased morbidity and mortality in peritoneal dialysis (PD) patients. Serum fructosamine may be a more reliable marker of glycemic control than HbA1c in dialysis patients.

METHODS

We evaluated the effects of a glucose-sparing PD regimen on serum fructosamine. In the multicenter, controlled IMPENDIA trial, eligible diabetic PD patients were randomized (1:1) to a 24-hour combination of a glucose sparing regimen (n = 89) or a glucose-based therapy (n = 91). Serum fructosamine and HbA1c were measured at baseline, 3 months and 6 months; fructosamine measurements were corrected for serum albumin (AlbF).

RESULTS

Serum fructosamine decreased from 297 to 253 µmol/l in the glucose-sparing group (95% confidence interval [CI] for the difference, -26 to -68, p < 0.001), and increased from 311 to 314 µmol/l in the glucose-only group (95% CI for the difference, -23 to +19, p = 0.87). The mean difference in change of fructosamine levels between groups at 6 months was 64 µmol/l (95% CI 29-99, p < 0.001). HbA1c decreased versus baseline in both groups (treatment difference 0.3%, p = 0.07). The correlation between AlbF and baseline fasting serum glucose was stronger than that seen between HbA1c and baseline fasting serum glucose (r = 0.47, p < 0.0001 and r = 0.31, p < 0.0001, respectively).

CONCLUSION

A glucose-sparing regimen (P-E-N) improved glycemic control as measured by serum fructosamine. Further studies are needed to establish fructosamine targets that will reduce the morbidity risk related to hyperglycemia in PD patients.

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.