Glycated Hemoglobin and Risk of Death in Diabetic Patients Treated With Hemodialysis: A Meta-analysis

Oral antidiabetics use among diabetic type 2 patients with chronic kidney disease. Do nephrologists take account of recommendations?

BACKGROUND

There is an increasing prevalence of diabetes type 2 and chronic kidney disease, challenging appropriate prescribing of oral anti-diabetic drugs (OADs).

METHODS

We have described the practice patterns of 13 nephrologists in 4 centers, in a cohort of 301 consecutive adult type 2 diabetic patients. Among oral anti-diabetic prescriptions, we have detailed drugs dosage for each subject, with 3 different formulae for estimating glomerular filtration rate (GFR) and its adequation according to the latest ERBP recommendations (2015). As individuals were mostly obese in this work, we also compare adequacy rates using both standard indexed CKD-EPI formula and CKD-EPI formula de-indexed from body surface area.

RESULTS

Using the CKD-EPI formula as the reference method for estimating GFR, 53.5% of patients were outside the recommendations, mostly for metformin (30% of the whole cohort) and for sitagliptin (17.9% of the whole cohort). With Cockcroft and Gault formula, 38.2% of persons were outside recommendations and 45.9% (p<0.001) with CKD-EPI de-indexed. Among individuals consulting a nephrologist for the first time (n=90), 61.1% were outside recommendations (p=0.1). Among those persons under diabetologist supervision (n=103), 63.1% were outside recommendations (p=0.09), and were taking significantly more often metformin and insulin.

CONCLUSION

We have found a substantial number of inadequate OAD prescriptions in type 2 diabetic patients with chronic kidney disease. The proportion of individuals outside guidelines was strongly affected by the method used for estimating GFR and by the type of practice, i.e., specialists versus general practitioners.

Predictor of cardiovascular risks in end stage renal failure patients on maintenance dialysis

Objective:

Cardiovascular disease (CVD) is the main cause of morbidity and premature mortality in end stage renal failure patients (ESRD) receiving dialysis. The aim of our study was to evaluate the impact of various risk factors in this group of high CVD risk patients in local population.

Methods:

We carried out a cross-sectional retrospective study in a single hospital. A total of 136 ESRF patients, consisted of 43 haemodialysis (HD) and 93 continuous ambulatory peritoneal dialysis (CAPD) patients, were recruited and followed up for 36 months duration. Midweek clinical and laboratory data were collected. The occurrence of existing and new CVD events was recorded.

Results:

Multiple Logistic Regression showed pre-existing cardiovascular event (odds ratio, 4.124; 95% confidence interval [CI], 0.990 to 17.187), elevated total cholesterol level (odds ratio, 0.550; 95% CI, 0.315 to 0.963), elevated serum phosphate level (odds ratio, 5.862; 95% CI, 1.041 to 33.024) and elevated random blood glucose level (odds ratio, 1.193; 95% CI, 1.012 to 1.406) were significantly associated with occurrence of CVD events.

Conclusions:

History of cardiovascular event before the initiation of dialysis, elevated level of serum phosphate and random blood glucose levels are the risk factors of CVD whereas paradoxically a high total cholesterol level has CVD protective effect towards the ESRF patients.

Improved glycemic control with teneligliptin in patients with type 2 diabetes mellitus on hemodialysis: Evaluation by continuous glucose monitoring

AIMS

Recent reports suggest that appropriate glycemic control without hypoglycemia could decrease mortality in patients with diabetes mellitus (DM) and end-stage renal disease (ESRD). However, an indication of oral anti-diabetic drugs is limited in this population. The aim of this study was to evaluate efficacy of teneligliptin, a novel DPP-4 inhibitor, by continuous glucose monitoring (CGM) in patients with type 2 DM (T2DM) on hemodialysis (HD).

METHODS

This 4-week, open label, single arm, intervention trial included 10 diabetic patients undergoing HD and with glycated albumin (GA) level of ≥18.3%. Teneligliptin treatment was administered on days with HD sessions (HD day) and on days without HD sessions (NHD day); blood glucose values were measured by CGM. The primary endpoint was improvement of glycemic control evaluated by area under the curve (AUC). As secondary endpoints, changes in GA, HbA1c and fasting plasma glucose (FPG) were evaluated.

RESULTS

Teneligliptin improved blood glucose AUC on both HD days (p=0.004), and NHD days (p=0.004). This was accompanied by a significant reduction in GA, HbA1c, and FPG, without severe hypoglycemia.

CONCLUSIONS

Teneligliptin is one of the useful options for glycemic control in T2DM patients undergoing HD.

Glycemic Control and Mortality in Diabetic Patients Undergoing Dialysis Focusing on the Effects of Age and Dialysis Type: A Prospective Cohort Study in Korea

Background

Active glycemic control has been proven to delay the onset and slow the progression of diabetic retinopathy, nephropathy, and neuropathy in diabetic patients, but the optimal level is obscure in end-stage renal disease. In this study, we evaluated the effect of hemoglobin A1c (HbA1c) on mortality of diabetic patients on dialysis, focusing on age and dialysis type.

Methods

Of 3,302 patients enrolled in the prospective cohort for end-stage renal disease in Korea between August 2008 and October 2013, 1,239 diabetic patients who had been diagnosed with diabetes or having HbA1c≥6.5% at the time of enrollment were analyzed. Age was categorized as <55, 55–64 and ≥65 years old. Age, sex, modified Charlson comorbidity index, hemoglobin, primary renal disease, body mass index, and dialysis duration were adjusted.

Results

A total of 873 patients received hemodialysis (HD) and 366 underwent peritoneal dialysis (PD). During the mean follow-up of 19.1 months, 141 patients died. Patients with poor glucose control (HbA1c≥8%) showed worse survival than patients with HbA1c<8% (hazard ratio [HR], 2.2; 95% confidence interval [CI], 1.48–3.29; P<0.001). Subgroup analysis divided by age revealed that HbA1c≥8% was a predictor of mortality in age <55 (HR, 4.3; 95% CI, 1.78–10.41; P = 0.001) and age 55–64 groups (HR, 3.3; 95% CI, 1.56–7.05; P = 0.002), but not in age ≥65 group. Combining dialysis type and age, poor glucose control negatively affected survival only in age < 55 group among HD patients, but it was significant in age < 55 and age 55–64 groups in PD patients. Deaths from infection were more prevalent in the PD group, and poor glucose control tended to correlate with more deaths from infection in PD patients (P = 0.050).

Conclusions

In this study, the effect of glycemic control differed according to age and dialysis type in diabetic patients. Thus, the target of glycemic control should be customized; further observational studies may strengthen the clinical relevance.

Evaluation and management of diabetic and non-diabetic hypoglycemia in end-stage renal disease

Patients with end-stage renal disease (ESRD) regardless of diabetes status are at increased risk of hypoglycemia with a resultant array of adverse clinical outcomes. Therefore, hypoglycemia should be thoroughly evaluated in ESRD patients. In diabetic dialysis patients, hypoglycemic agents and nutritional alterations can trigger hypoglycemia in the background of diminished gluconeogenesis, reduced insulin clearance by the kidney and improved insulin sensitivity following initiation of renal replacement therapy. Detailed evaluation of antidiabetic regimen and nutritional patterns, patient education on self-monitoring of blood glucose and/or referral to a diabetes specialist may reduce risk of subsequent hypoglycemia. In certain situations, it is important to recognize the possibility of non-diabetic causes of hypoglycemia in patients with diabetes and to avoid treating pseudo-hyperglycemia caused by glucose- non-specific glucometers in patients utilizing icodextrin-based solutions for peritoneal dialysis. Adrenal insufficiency, certain medications, malnutrition and/or infection are among the most common causes of hypoglycemia in non-diabetic ESRD patients, and they should be suspected after exclusion of inadvertent use of hypoglycemic agents. The goal of this review article is to summarize approaches and recommendations for the work up and treatment of hypoglycemia in ESRD.

What is the Role of HbA1c in Diabetic Hemodialysis Patients?

The definition of a good glycemic control in patients with diabetes mellitus on hemodialysis is far from settled. In the general population, hemoglobin A1c is highly correlated with the average glycemia of the last 8-12 weeks. However, in hemodialysis patients, the correlation of hbA1c with glycemia is weaker as it also reflects changes in hemoglobin characteristics and red blood cells half-life. As expected, studies show that the association between HbA1c and outcomes in these patients differ from the general population. Therefore, the value of HbA1c in the treatment of hemodialysis patients has been questioned. Guidelines are generally cautious in their recommendations about possible targets of HbA1c in this population. Indeed, the risk of not treating hyperglycemia should be weighed against the particularly high risk of precipitating hypoglycemia in dialysis patients. In this review, a critical analysis of the current role of HbA1c in the care of hemodialysis patients is presented.

Haemodialysis-induced hypoglycaemia and glycaemic disarrays

In patients with diabetes receiving chronic haemodialysis, both very high and low glucose levels are associated with poor outcomes, including mortality. Conditions that are associated with an increased risk of hypoglycaemia in these patients include decreased gluconeogenesis in the remnant kidneys, deranged metabolic pathways, inadequate nutrition, decreased insulin clearance, glucose loss to the dialysate and diffusion of glucose into erythrocytes during haemodialysis. Haemodialysis-induced hypoglycaemia is common during treatments with glucose-free dialysate, which engenders a catabolic status similar to fasting; this state can also occur with 5.55 mmol/l glucose-containing dialysate. Haemodialysis-induced hypoglycaemia occurs more frequently in patients with diabetes than in those without. Insulin therapy and oral hypoglycaemic agents should, therefore, be used with caution in patients on dialysis. Several hours after completion of haemodialysis treatment a paradoxical rebound hyperglycaemia may occur via a similar mechanism as the Somogyi effect, together with insulin resistance. Appropriate glycaemic control tailored for patients on haemodialysis is needed to avoid haemodialysis-induced hypoglycaemia and other glycaemic disarrays. In this Review we summarize the pathophysiology and current management of glycaemic disarrays in patients on haemodialysis.

Glycaemic Control Impact on Renal Endpoints in Diabetic Patients on Haemodialysis

Objective. To identify the number of haemodialysis patients with diabetes in a large NHS Trust, their current glycaemic control, and the impact on other renal specific outcomes. Design. Retrospective, observational, cross-sectional study. Methods. Data was collected from an electronic patient management system. Glycaemic control was assessed from HbA1c results that were then further adjusted for albumin (Alb) and haemoglobin (Hb). Interdialytic weight gains were analysed from weights recorded before and after dialysis, 2 weeks before and after the most recent HbA1c date. Amputations were identified from electronic records. Results. 39% of patients had poor glycaemic control (HbA1c > 8%). Adjusted HbA1c resulted in a greater number of patients with poor control (55%). Significant correlations were found with interdialytic weight gains (P < 0.02, r = 0.14), predialysis sodium (P < 0.0001, r = −1.9), and predialysis bicarbonate (P < 0.02, r = 0.12). Trends were observed with albumin and C-reactive protein. Patients with diabetes had more amputations (24 versus 2). Conclusion. Large number of diabetic patients on haemdialysis have poor glycaemic control. This may lead to higher interdialytic weight gains, larger sodium and bicarbonate shifts, increased number of amputations, and possibly increased inflammation and decreased nutritional status. Comprehensive guidelines and more accurate long-term tests for glycaemic control are needed.

The Effect of Glycated Hemoglobin and Albumin-Corrected Glycated Serum Protein on Mortality in Diabetic Patients Receiving Continuous Peritoneal Dialysis

OBJECTIVE

To explore the effect of glycated hemoglobin (HbA1c) and albumin-corrected glycated serum proteins (Alb-GSP) on the mortality of diabetic patients receiving continuous peritoneal dialysis (PD).

METHODS

In this single-center retrospective cohort study, incident diabetic PD patients from January 1, 2006, to December 31, 2010, were recruited, and followed up until December 31, 2011. The effect of HbA1c and Alb-GSP on mortality was evaluated by Cox proportional hazards models.

RESULTS

A total of 200 patients (60% male, mean age 60.3 ± 10.6 years) with a mean follow-up of 29.0 months (range: 4.3 - 71.5 months) were recruited. Sixty-four patients died during the follow-up period, of whom 21 died of cardiovascular disease (CVD). Mean values for HbA1c, GSP and Alb-GSP were 6.7% (range: 4.1 - 12.5%), 202 μmol/L (range: 69 - 459 μmol/L), and 5.78 μmol/g (range: 2.16 - 14.98 μmol/g), respectively. The concentrations of GSP and Alb-GSP were closely correlated with HbA1c (r = 0.41, p < 0.001 and r = 0.45, p < 0.001, respectively). In multivariate Cox proportional hazards models, patients with HbA1c ≥ 8% were associated with increased risk of all-cause mortality (hazard ratio [HR] = 2.29, 95% confidence interval [CI]: 1.06 - 4.96, p = 0.04), but no increased mortality in patients with 6.0% ≤ HbA1c ≤ 7.9%. Patients with Alb-GSP ≤ 4.50 μmol/g had increased all-cause and non-cardiovascular mortality (HR = 2.42, 95% CI: 1.13 - 5.19, p = 0.02; and HR = 2.98, 95% CI: 1.05 - 8.48, p = 0.04 respectively).

CONCLUSIONS

Increased HbA1c and decreased Alb-GSP may be associated with poorer survival in diabetic PD patients, with a non-significant trend observed for poorer survival with the highest level of Alb-GSP.

[Significance of hemoglobin A1C in the management of diabetes in dialysis patients]

According to latest guidelines hemoglobin A1C plays a central role in the diagnosis of diabetes mellitus. It is well-known from epidemiologic studies that a high rate of diabetic patients enters into dialysis programs and these patients have an unfavourable mortality outcome. Based on surveys conducted in recent years in this patient group, hemoglobin A1C has an important role in assessing carbohydrate metabolism. However, there are several factors independent of blood glucose may affect hemoglobin A1C values both in hemodialysis and peritoneal dialysis patients. Hemodialysis disturbs hemoglobin A1c assessment because of an accelerated turnover of lost red blood cells. During peritoneal dialysis a considerable amount of glucose may be absorbed from the peritoneal solutions that may influence hemoglobin A1C level. Several alternative markers such as glycated albumin and fructosamine have been evaluated but they failed to have prognostic advantage. It has been concluded that among dialysis patients the hemoglobin A1C range between 6.5 and 8% is associated with the lowest mortality risk.

Predicting mortality in patients with diabetes starting dialysis

Background

While some prediction models have been developed for diabetic populations, prediction rules for mortality in diabetic dialysis patients are still lacking. Therefore, the objective of this study was to identify predictors for 1-year mortality in diabetic dialysis patients and use these results to develop a prediction model.

Methods

Data were used from the Netherlands Cooperative Study on the Adequacy of Dialysis (NECOSAD), a multicenter, prospective cohort study in which incident patients with end stage renal disease (ESRD) were monitored until transplantation or death. For the present analysis, patients with DM at baseline were included. A prediction algorithm for 1-year all-cause mortality was developed through multivariate logistic regression. Candidate predictors were selected based on literature and clinical expertise. The final model was constructed through backward selection. The model's predictive performance, measured by calibration and discrimination, was assessed and internally validated through bootstrapping.

Results

A total of 394 patients were available for statistical analysis; 82 (21%) patients died within one year after baseline (3 months after starting dialysis therapy). The final prediction model contained seven predictors; age, smoking, history of macrovascular complications, duration of diabetes mellitus, Karnofsky scale, serum albumin and hemoglobin level. Predictive performance was good, as shown by the c-statistic of 0.810. Internal validation showed a slightly lower, but still adequate performance. Sensitivity analyses showed stability of results.

Conclusions

A prediction model containing seven predictors has been identified in order to predict 1-year mortality for diabetic incident dialysis patients. Predictive performance of the model was good. Before implementing the model in clinical practice, for example for counseling patients regarding their prognosis, external validation is necessary.