Reducing cardiometabolic risk in peritoneal dialysis patients: role of the dialysis solution

Comparison of clinical outcome between incremental peritoneal dialysis and conventional peritoneal dialysis: a propensity score matching study

Background

Incremental peritoneal dialysis (iPD) can be useful in patients with residual renal function (RRF). RRF was well preserved and similar survival was shown in iPD compared to conventional PD (cPD) in previous study. However, the long-term survival of iPD remains unclear compared to cPD in diabetic patients. This study evaluated whether patient survival, hospitalization and peritonitis, and PD survival in iPD were lower than cPD or not.

Methods

We conducted a 12-year retrospective observational study of 303 PD patients (232 cPD and 71 iPD) using propensity score matching by age, gender, and diabetes mellitus (DM). Finally, 78 cPD patients and 39 iPD patients were included and 44 patients had DM. Incremental PD was defined as starting PD with two or three manual exchanges per day.

Results

The median duration of iPD was 24.1 months and iPD had higher RRF than cPD. Compared to cPD, the patient survival, PD survival and hospitalization benefits were not found in iPD but diabetic iPD patients had significantly longer survival and less hospitalization. Cumulative risk for peritonitis was lower iPD and PD duration of iPD was longer than those of cPD. The iPD was an independent factor associated with survival in patients with DM.

Conclusions

Incremental PD may be a safe PD modality to initiate and maintain PD in less uremic patients with tolerable RRF. Incremental PD would be a benefit for survival in diabetic patients. Further prospective studies are necessary to confirm the effectiveness of iPD in PD patients with similar RRF.

International comparison of peritoneal dialysis prescriptions from the Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS)

Background:

We describe peritoneal dialysis (PD) prescription variations among Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS) participants on continuous ambulatory PD (CAPD) and automated PD (APD; n = 4657) from Australia/New Zealand (A/NZ), Canada, Japan, Thailand, United Kingdom (UK), and United States (US).

Results:

CAPD was more commonly used in Thailand and Japan, while APD predominated over CAPD in A/NZ, Canada, the US, and the UK. Total prescribed PD volume normalized to the surface area was the highest in Thailand and the lowest in Japan (for both APD and CAPD) and the UK (for CAPD). PD patients from Thailand had the lowest residual urine volume and residual renal urea clearance, yet achieved the highest dialysis urea clearance. Japanese patients had the lowest dialysis urea clearances for both APD and CAPD. Despite having similar urine volumes to patients in A/NZ, Canada, Japan, and the UK, US CAPD and APD patients used 2.5% and 3.86% glucose PD solutions more frequently, whereas fewer than 25% of these patients used icodextrin. Over half of the patients in A/NZ, Canada, the UK, and Japan used icodextrin, whereas it was hardly used in Thailand. Japan and Thailand were more likely to use 1.5% glucose solutions for their PD prescription.

Conclusions:

There are considerable international variations in PD modality use and prescription patterns that translate into important differences in achieved dialysis clearances. Ongoing recruitment of additional PDOPPS participants and accrual of follow-up time will allow us to test the associations between specific PD prescription regimens and clinical and patient-reported outcomes.

Association between Dyslipidemia and Peritoneal Dialysis Technique Survival

BACKGROUND:

A large body of research has investigated the effects of pro-atherogenic lipid profile on cardiovascular diseases (CVD) in peritoneal dialysis (PD) patients. However, there is a general lack of research on the association between atherogenic dyslipidemia and PD technique survival.

AIM:

The study aimed to define the association between dyslipidemia and PD technique survival.

METHODS:

It was a prospective single-centre observational study involving 40 outpatients on continuous ambulatory PD treatment for more than 3 months between 2010 and 2016 in a single centre in Ukraine. There were 27 males and 13 females. The mean age of the participants was 49.3 ± 12.2 years. The primary outcome measures were all-cause technique failure.

RESULTS:

Atherogenic dyslipidemia was identified in 28/40 (70 %) patients and correlated with PD adequacy parameters. During the 36-month- follow-up period technique failure occurred in 2/12 (16.6 %) patients with atherogenic dyslipidemia compared with 12 / 28 (42.9 %) patients without atherogenic dyslipidemia (χ² = 2.5; p = 0.12). In the univariate Cox regression model, atherogenic dyslipidemia at baseline was significantly associated with a higher risk of all-cause PD technique failure (HR 4.5; 95% CI 1.6 to 12.9; χ² = 5.5, p = 0.019).

CONCLUSION:

The presence of atherogenic dyslipidemia was significantly associated with a higher risk of technique failure in PD patients. This is an important issue for future research. Further well-designed clinical trials are needed to determine the impact of dyslipidemia on PD adequacy and technique survival.

Regimen-related Mortality Risk in Patients Undergoing Peritoneal Dialysis Using Hypertonic Glucose Solution: A Retrospective Cohort Study

OBJECTIVES

The main purpose of this study was to quantify the risk of mortality linked to various regimens of hypertonic peritoneal dialysis (PD) solution.

METHODS

A retrospective cohort study of patients using home-based PD was carried out. The prescribed regimen of glucose-based PD solution for all patients, determined on the basis of their individual conditions, was extracted from their medical chart records. The primary outcome was death. The treatment regimens were categorized into 3 groups according to the type of PD solution used: original PD (1.5% glucose), shuffle PD (1.5 and 2.5% glucose), and serialized PD (2.5 and 4.5% glucose). Multivariate analysis (using the Weibull model) was applied to comprehensively examine survival probabilities related to the explanatory variable, while adjusting for other potential confounders.

RESULTS

Of 300 consecutive patients, 38% died over a median follow-up time of 30 months (interquartile range: 15-46 months). Multivariate analysis showed that a treatment regimen with continued higher-strength PD solution (serialized PD) resulted in a lower survival rate than when the conventional strength solution was used (adjusted hazard ratio, 2.6; 95% confidence interval, 1.6 to 4.6, p<0.01). Five interrelated risk factors (age, length of time on PD, hemoglobin levels, albumin levels, and oliguria) were significant predictors contributing to the outcome.

CONCLUSIONS

Frequent exposure to high levels of glucose PD solution significantly contributed to a 2-fold higher rate of death, especially when hypertonic glucose was prescribed continuously.

Peritoneal and Systemic Responses of Obese Type II Diabetic Rats to Chronic Exposure to a Hyperbranched Polyglycerol-Based Dialysis Solution

Metabolic syndrome (MetS) is commonly observed among peritoneal dialysis (PD) patients, and hyperbranched polyglycerol (HPG) is a promising glucose-sparing osmotic agent for PD. However, the biocompatibility of a HPG-based PD solution (HPG) in subjects with MetS has not been investigated. This study compared the local and systemic effects of a HPG solution with conventional physioneal (PYS) and icodextrin (ICO) PD solutions in rats with MetS. Obese type 2 diabetic ZSF1 rats received a daily intraperitoneal injection of PD solutions (10 mL) for 3 months. The peritoneal membrane (PM) function was determined by ultrafiltration (UF), and the systemic responses were determined by profiling blood metabolic substances, cytokines and oxidative status. Tissue damage was assessed by histology. At the end of the 3-month treatment with PD solutions, PM damage and UF loss in both the PYS and ICO groups were greater than those in the HPG group. Blood analyses showed that compared to the baseline control, the rats in the HPG group exhibited a significant decrease only in serum albumin and IL-6 and a minor glomerular injury, whereas in both the PYS and ICO groups, there were more significant decreases in serum albumin, antioxidant activity, IL-6, KC/GRO (CXCL1) and TNF-α (in ICO only) as well as a more substantial glomerular injury compared to the HPG group. Furthermore, PYS increased serum creatinine, serum glucose and urine production. In conclusion, compared to PYS or ICO solutions, the HPG solution had less adverse effects locally on the PM and systemically on distant organs (e.g. kidneys) and the plasma oxidative status in rats with MetS.

Hyperbranched polyglycerol is superior to glucose for long-term preservation of peritoneal membrane in a rat model of chronic peritoneal dialysis

Background

Replacing glucose with a better biocompatible osmotic agent in peritoneal dialysis (PD) solutions is needed in PD clinic. We previously demonstrated the potential of hyperbranched polyglycerol (HPG) as a replacement for glucose. This study further investigated the long-term effects of chronic exposure to HPG as compared to a glucose-based conventional PD solution on peritoneal membrane (PM) structure and function in rats.

Methods

Adult male Wistar rats received once-daily intraperitoneal injection of 10 mL of HPG solution (1 kDa, HPG 6%) compared to Physioneal™ 40 (PYS, glucose 2.27%) or electrolyte solution (Control) for 3 months. The overall health conditions were determined by blood chemistry analysis. The PM function was determined by ultrafiltration, and its injury by histological and transcriptome-based pathway analyses.

Results

Here, we showed that there was no difference in the blood chemistry between rats receiving the HPG and the Control, while PYS increased serum alkaline phosphatase, globulin and creatinine and decreased serum albumin. Unlike PYS, HPG did not significantly attenuate PM function, which was associated with smaller change in both the structure and the angiogenesis of the PM and less cells expressing vascular endothelial growth factor, α-smooth muscle actin and MAC387 (macrophage marker). The pathway analysis revealed that there were more inflammatory signaling pathways functioning in the PM of PYS group than those of HPG or Control, which included the signaling for cytokine production in both macrophages and T cells, interleukin (IL)-6, IL-10, Toll-like receptors, triggering receptor expressed on myeloid cells 1 and high mobility group box 1.

Conclusions

The results from this experimental study indicate the superiority of HPG to glucose in the preservation of the peritoneum function and structure during the long-term PD treatment, suggesting the potential of HPG as a novel osmotic agent for PD.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-016-1098-z) contains supplementary material, which is available to authorized users.

Fat tissue and inflammation in patients undergoing peritoneal dialysis

Background

Body weight has been increasing in the general population and is an established risk factor for hypertension, diabetes, and all-cause and cardiovascular mortality. Patients undergoing peritoneal dialysis (PD) gain weight, mainly during the first months of treatment. The aim of this study was to assess the relationship between body composition and metabolic and inflammatory status in patients undergoing PD.

Methods

This was a prospective, non-interventional study of prevalent patients receiving PD. Body composition was studied every 3 months using bioelectrical impedance (BCM^®). We performed linear regression for each patient, including all BCM^® measurements, to calculate annual changes in body composition. Thirty-one patients in our PD unit met the inclusion criteria.

Results

Median follow-up was 26 (range 17–27) months. Mean increase in weight was 1.8 ± 2.8 kg/year. However, BCM^® analysis revealed a mean increase in fat mass of 3.0 ± 3.2 kg/year with a loss of lean mass of 2.3 ± 4.1 kg/year during follow-up. The increase in fat mass was associated with the conicity index, suggesting that increases in fat mass are based mainly on abdominal adipose tissue. Changes in fat mass were directly associated with inflammation parameters such as C-reactive protein (r = 0.382, P = 0.045) and inversely associated with high-density lipoprotein cholesterol (r=−0.50, P = 0.008).

Conclusions

Follow-up of weight and body mass index can underestimate the fat mass increase and miss lean mass loss. The increase in fat mass is associated with proinflammatory state and alteration in lipid profile.

Biphasic Regulation of Lipid Metabolism: A Meta-Analysis of Icodextrin in Peritoneal Dialysis

Objectives. The objective of this systematic meta-analysis was to study the impact of icodextrin (ICO) on lipid profiles. Methods. MEDLINE, PubMed, Embase, Chinese Biomedical Literature, and the Cochrane Library and Reference lists were searched (last search September 2014) in accordance with the Cochrane Handbook for Systematic Reviews of Interventions. Results. Searches identified 13 eligible trials with a total of 850 patients. The differentials of total cholesterol (TC) and free fatty acid (FFA) in the ICO group were greater than those in the GLU group. Metaregression analysis showed that TC levels positively correlated with its baseline levels. In the subgroup of patients with dialysis duration more than 6 months, TC and TG in the ICO group were less. In pooled data from cross-sectional studies, differential of TG in the ICO group was less. In the subgroup of patients with diabetes (Martikainen et al., 2005, Sniderman et al., 2014, and Takatori et al., 2011), differential of high-density lipoprotein cholesterol (HDL-C) in the ICO group was less. There was no significant effect on low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C), or lipoprotein(a). Conclusions. ICO may be beneficial to lipid metabolism, especially for its biphasic regulation of plasma TC levels.

Skin Autofluorescence and Mortality in Patients on Peritoneal Dialysis

Skin autofluorescence (SAF) is a proven prognostic factor of mortality in hemodialysis patients. Traditional and nontraditional risk factors are almost equivalent in peritoneal dialysis (PD), and cardiovascular disease (CVD) is the leading cause of death. Moreover, peritoneal glucose absorption accelerates the degenerative processes of connective tissues as in diabetes. In our study, we examined the predictive value of SAF for total mortality in the PD population. Data were collected from 198 prevalently adult Caucasian PD patients. One hundred twenty-six patients (mean age 66.2 y, men [n = 73], diabetes ratio 75/126) had anamnestic CVD (coronary heart disease, cerebrovascular disease, peripheral arterial disease). Initially, we evaluated factors affecting SAF and CVD by multivariate linear regression. Survival rates were estimated by recording clinical and demographic data associated with mortality during a 36-month follow-up using the Kaplan-Meier method. Analyses were further stratified based on the presence or absence of CVD and SAF levels above or below the upper tercile 3.61 arbitrary units.Skin autofluorescence was influenced by CVD (P < 0.01, 95% confidence interval [CI] 0.1-0.5) and white blood cell counts (P < 0.001, 95% CI 0.031-0.117). According to the Spearman correlation, SAF correlated with peritoneal cumulative glucose exposure (P = 0.02) and elapsed time in PD (P = 0.008). CVD correlated with age (P < 0.001, 95% CI 1.24-1.65) and diabetes (P < 0.001, 95% CI 2.58-10.66). More deaths were observed in the high SAF group than in the low SAF group (34/68 vs 44/130; P = 0.04). Comparing the CVD(-) low SAF group survival (mean 33.9 mos, standard error [SE] 1.39) to CVD(+) low SAF (mean 30.5 mos, SE 1.37, P = 0.03) and to CVD(+) high SAF group (mean 27.1 mos, SE 1.83, P = 0.001), the difference was significant.In conclusion, among PD patients, SAF values over 3.61 arbitrary units seem to be a predictor of mortality. The relationship among peritoneal glucose exposure, CVD, and diabetes suggests its suitability to characterize systemic cumulative glucose load in this patient population.

Visceral fat area is associated with HbA1c but not dialysate-related glucose load in nondiabetic PD patients

Factors associated with increased visceral fat area (VFA) have been well documented in the general population but rarely explored in nondiabetic individuals on peritoneal dialysis (PD). As glycosylated hemoglobin (HbA1c) is positively correlated with VFA in diabetic patients, we hypothesized that the same correlation would exist in nondiabetic PD patients. We enrolled 105 nondiabetic patients who had undergone chronic PD for more than 3 months. Each subject underwent an abdominal computed tomography (CT) scan, and the umbilicus cut was analyzed for VFA. VFA values, corrected for body mass index and subjected to natural logarithm transformations, were examined to determine whether they were correlated with HbA1c and other parameters. PD dialysates prescribed at the time of enrollment were recorded to calculate glucose load. We found that when 105 nondiabetic PD patients were classified according to tertiles of HbA1c, higher HbA1c was associated with larger VFA. Multiple linear regression analysis revealed that HbA1c was an independent determinant of VFA, while glucose load and other PD-specific factors were not. In summary, HbA1c, but not PD-related glucose load, was positively correlated with VFA in nondiabetic PD patients, suggesting clinical utility of HbA1c in the PD population.

Clinical practice considerations and review of the literature for the Use of DPP-4 inhibitors in patients with type 2 diabetes and chronic kidney disease

OBJECTIVE

Many commonly prescribed agents for the treatment of type 2 diabetes (T2DM) have important restrictions on use in patients with renal impairment. Prescribing information and published data on dipeptidyl peptidase-4 (DPP-4) inhibitors indicate that these agents are suitable for use in this patient population. However, a recent database analysis indicated prevalent underrecognition of renal impairment and limited awareness of prescription considerations associated with DPP-4 inhibitor use in patients with renal impairment. Thus, this article reviews recent literature on the safety, efficacy, pharmacokinetics, and clinical use of DPP-4 inhibitors in patients with renal impairment and T2DM.

METHODS

PubMed searches were conducted for literature describing the use of DPP-4 inhibitors in patients with renal impairment.

RESULTS

Most DPP-4 inhibitors are characterized by significant renal clearance. As a result, pharmacokinetics are measurably affected by the presence of renal impairment; plasma exposure of DPP-4 inhibitors and their metabolites may increase by up to sevenfold in severe impairment/end-stage renal disease. The exception in this case is linagliptin, which is eliminated predominantly via the hepatobiliary system. Our search identified several studies that evaluated specific doses of DPP-4 inhibitors in patients with renal impairment and reported positive safety and efficacy results.

CONCLUSIONS

Overall, DPP-4 inhibitors are an effective means of controlling blood glucose in patients with T2DM and renal impairment. Considering the restrictions associated with many other antihyperglycemic agents when used in patients with renal impairment, DPP-4 inhibitors should be a considered as a treatment option in this patient population.

Dynamic O-linked N-acetylglucosamine modification of proteins affects stress responses and survival of mesothelial cells exposed to peritoneal dialysis fluids

The ability of cells to respond and survive stressful conditions is determined, in part, by the attachment of O-linked N-acetylglucosamine (O-GlcNAc) to proteins (O-GlcNAcylation), a post-translational modification dependent on glucose and glutamine. This study investigates the role of dynamic O-GlcNAcylation of mesothelial cell proteins in cell survival during exposure to glucose-based peritoneal dialysis fluid (PDF). Immortalized human mesothelial cells and primary mesothelial cells, cultured from human omentum or clinical effluent of PD patients, were assessed for O-GlcNAcylation under normal conditions or after exposure to PDF. The dynamic status of O-GlcNAcylation and effects on cellular survival were investigated by chemical modulation with 6-diazo-5-oxo-L-norleucine (DON) to decrease or O-(2-acetamido-2-deoxy-D-glucopyranosylidene)amino N-phenyl carbamate (PUGNAc) to increase O-GlcNAc levels. Viability was decreased by reducing O-GlcNAc levels by DON, which also led to suppressed expression of the cytoprotective heat shock protein 72. In contrast, increasing O-GlcNAc levels by PUGNAc or alanyl-glutamine led to significantly improved cell survival paralleled by higher heat shock protein 72 levels during PDF treatment. Addition of alanyl-glutamine increased O-GlcNAcylation and partly counteracted its inhibition by DON, also leading to improved cell survival. Immunofluorescent analysis of clinical samples showed that the O-GlcNAc signal primarily originates from mesothelial cells. In conclusion, this study identified O-GlcNAcylation in mesothelial cells as a potentially important molecular mechanism after exposure to PDF. Modulating O-GlcNAc levels by clinically feasible interventions might evolve as a novel therapeutic target for the preservation of peritoneal membrane integrity in PD.

Influence of low-glucose peritoneal dialysis on serum lipids and apolipoproteins in the IMPENDIA/EDEN trials

BACKGROUND

Glucose, the conventional osmotic agent in peritoneal dialysis (PD) solutions, may contribute to atherogenic dyslipoproteinemia and increased cardiovascular risk.

OBJECTIVE

To determine whether a low-glucose PD regimen may improve the serum lipid and lipoprotein profile in patients with diabetes.

METHODS

A prospective, open-label, parallel group, multinational, randomized, controlled trial with a 6-month follow-up, comprising 251 patients with diabetes receiving PD. Patients were randomized to a low-glucose PD regimen (dextrose-based PD solution plus icodextrin, a starch polymer, and amino acids) or a conventional PD regimen (dextrose PD solutions). Serum lipid and apolipoprotein profiles were determined at baseline and 3 and 6 months.

RESULTS

Serum triglycerides, very low-density-lipoprotein cholesterol, and apolipoprotein B (apoB) decreased significantly in the intervention group at both 3 and 6 months compared with baseline (serum triglycerides: median change at 3 months -0.5 mmol/L, P < .001, at 6 months -0.3 mmol/L, P < .001; very low-density-lipoprotein cholesterol: -0.3 mg/dL, P < .001; -0.3 mg/dL, P < .001; and apoB: -8.5 mg/dL, P < .001; -3.6 mg/dL, P = .043, respectively) and also compared with the control group. In contrast, apoB levels increased significantly in the control group at 3 and 6 months compared with baseline (5.3 mg/dL, P = .041; 5.2 mg/dL, P = .007, respectively). Percentage of patients on lipid-lowering medications at baseline and intensity of therapy was equivalent in each group. The apoB decrease was not affected by lipid-lowering medications in the intervention group.

CONCLUSION

A low glucose-PD regimen significantly improved the atherogenic lipoprotein phenotype compared with PD patients treated with a conventional glucose regimen.

Low-Polydispersity Glucose Polymers as Osmotic Agents for Peritoneal Dialysis

♦

BACKGROUND

Peritoneal dialysis (PD) solutions containing icodextrin as the osmotic agent have advantages during long dwells. The glucose polymers that constitute icodextrin are a heterogeneous mix of molecules with a polydispersity [ratio of weight-average to number-average molecular weight (Mw/Mn)] of approximately 2.6. The present study evaluates whether modifications in the polydispersity and concentration of glucose polymers can improve ultrafiltration (UF) without an associated increase in carbohydrate absorption (CA). ♦

METHODS

Computer simulations using a three-pore model of peritoneal transport during a long dwell in PD patients predict that, in general, compared with 7.5% icodextrin, glucose polymers with a Mw greater than or equal to 7.5 kDa, a polydispersity less than 2.6, and concentrations greater than 7% could achieve higher UF without higher CA. Based on the simulations, we hypothesized that, compared with 7.5% icodextrin, glucose polymers with a Mw of 18 - 19 kDa and a polydispersity of 2.0 at 11% concentration could achieve higher UF without a higher CA. We tested this hypothesis in experimental studies using 8-hour dwells in New Zealand White rabbits. In those studies, UF was measured by complete fluid collection, and CA was measured by subtracting the total carbohydrate in the collected fluid from the carbohydrate initially infused. ♦

RESULTS

The UF was higher with 11% 19 kDa glucose polymer than with 7.5% icodextrin (mean ± standard deviation: 89 ± 31 mL vs 49 ± 15 mL; p = 0.004) without higher CA (5.2 ± 0.9 g vs 5.0 ± 0.9 g, p = 0.7). Similar results were seen with the 11% 18 kDa glucose polymer, which, compared with 7.5% icodextrin, resulted in higher UF (mean ± standard deviation: 96 ± 18 mL vs 66 ± 17 mL; p < 0.001) without higher CA (4.8 ± 0.7 g vs 5.2 ± 0.6 g, p = 0.2). ♦

CONCLUSIONS

The findings demonstrate that, compared with 7.5% icodextrin solution, long-dwell PD solutions containing 11% glucose polymers with a Mw of 18-19 kDa and a polydispersity of 2.0 can provide higher UF without higher CA.

Stability of the combination of ceftazidime and cephazolin in icodextrin or pH neutral peritoneal dialysis solution

INTRODUCTION

The objective of this study was to investigate the stability of ceftazidime and cephazolin in a 7.5% icodextrin or pH neutral peritoneal dialysis (PD) solution.

METHODS

Ceftazidime and cephazolin were injected into either a 7.5% icodextrin or pH neutral PD bag to obtain the concentration of 125 mg/L of each antibiotic. A total of nine 7.5% icodextrin or pH neutral PD bags containing ceftazidime and cephazolin were prepared and stored at 1 of 3 different temperatures: 4°C in a domestic refrigerator; 25°C at room temperature; or 37°C (body temperature) in an incubator. An aliquot was withdrawn immediately before (0 hour) or after 12, 24, 48, 96, 120, 144, 168 and 336 hours of storage. Each sample was analyzed in duplicate for the concentration of ceftazidime and cephazolin using a stability-indicating high-performance liquid chromatography technique. Ceftazidime and cephazolin were considered stable if they retained more than 90% of their initial concentration. Samples were also assessed for pH, colour changes and evidence of precipitation immediately after preparation and on each day of analysis.

RESULTS

Ceftazidime and cephazolin in both types of PD solution retained more than 90% of their initial concentration for 168 and 336 hours respectively when stored at 4°C. Both of the antibiotics lost more than 10% of the initial concentration after 24 hours of storage at 25 or 37°C. There was no evidence of precipitation at any time under the tested storage conditions. Change in the pH and color was observed at 25 and 37°C, but not at 4°C.

CONCLUSION

Premixed ceftazidime and cephazolin in a 7.5% icodextrin or pH neutral PD solution is stable for at least 168 hours when refrigerated. This allows the preparation of PD bags in advance, avoiding the necessity for daily preparation. Both the antibiotics are stable for at least 24 hours at 25 and 37°C, permitting storage at room temperature and pre-warming of PD bags to body temperature prior to its administration.

Randomized, controlled trial of glucose-sparing peritoneal dialysis in diabetic patients

Glucose-containing peritoneal dialysis solutions may exacerbate metabolic abnormalities and increase cardiovascular risk in diabetic patients. Here, we examined whether a low-glucose regimen improves metabolic control in diabetic patients undergoing peritoneal dialysis. Eligible patients were randomly assigned in a 1:1 manner to the control group (dextrose solutions only) or to the low-glucose intervention group (IMPENDIA trial: combination of dextrose-based solution, icodextrin and amino acids; EDEN trial: a different dextrose-based solution, icodextrin and amino acids) and followed for 6 months. Combining both studies, 251 patients were allocated to control (n=127) or intervention (n=124) across 11 countries. The primary endpoint was change in glycated hemoglobin from baseline. Mean glycated hemoglobin at baseline was similar in both groups. In the intention-to-treat population, the mean glycated hemoglobin profile improved in the intervention group but remained unchanged in the control group (0.5% difference between groups; 95% confidence interval, 0.1% to 0.8%; P=0.006). Serum triglyceride, very-low-density lipoprotein, and apolipoprotein B levels also improved in the intervention group. Deaths and serious adverse events, including several related to extracellular fluid volume expansion, increased in the intervention group, however. These data suggest that a low-glucose dialysis regimen improves metabolic indices in diabetic patients receiving peritoneal dialysis but may be associated with an increased risk of extracellular fluid volume expansion. Thus, use of glucose-sparing regimens in peritoneal dialysis patients should be accompanied by close monitoring of fluid volume status.

Exploring metabolic dysfunction in chronic kidney disease

Impaired kidney function and chronic kidney disease (CKD) leading to kidney failure and end-stage renal disease (ESRD) is a serious medical condition associated with increased morbidity, mortality, and in particular cardiovascular disease (CVD) risk. CKD is associated with multiple physiological and metabolic disturbances, including hypertension, dyslipidemia and the anorexia-cachexia syndrome which are linked to poor outcomes. Specific hormonal, inflammatory, and nutritional-metabolic factors may play key roles in CKD development and pathogenesis. These include raised proinflammatory cytokines, such as interleukin-1 and −6, tumor necrosis factor, altered hepatic acute phase proteins, including reduced albumin, increased C-reactive protein, and perturbations in normal anabolic hormone responses with reduced growth hormone-insulin-like growth factor-1 axis activity. Others include hyperactivation of the renin-angiotensin aldosterone system (RAAS), with angiotensin II and aldosterone implicated in hypertension and the promotion of insulin resistance, and subsequent pharmacological blockade shown to improve blood pressure, metabolic control and offer reno-protective effects. Abnormal adipocytokine levels including leptin and adiponectin may further promote the insulin resistant, and proinflammatory state in CKD. Ghrelin may be also implicated and controversial studies suggest activities may be reduced in human CKD, and may provide a rationale for administration of acyl-ghrelin. Poor vitamin D status has also been associated with patient outcome and CVD risk and may indicate a role for supplementation. Glucocorticoid activities traditionally known for their involvement in the pathogenesis of a number of disease states are increased and may be implicated in CKD-associated hypertension, insulin resistance, diabetes risk and cachexia, both directly and indirectly through effects on other systems including activation of the mineralcorticoid receptor. Insight into the multiple factors altered in CKD may provide useful information on disease pathogenesis, clinical assessment and treatment rationale such as potential pharmacological, nutritional and exercise therapies.

Relationship between glucose exposure via peritoneal dialysis solutions and coronary artery calcification in non-diabetic peritoneal dialysis patients

INTRODUCTION

Vascular calcification is frequent in dialysis patients and is associated with increased mortality. Impaired glucose metabolism is proposed as a contributing factor for vascular calcification. We investigated whether glucose exposure via dialysate may have a role in vascular calcification in non-diabetic peritoneal dialysis patients.

METHOD

We measured coronary artery calcification by multi-slice computerized tomography in 50 prevalent non-diabetic peritoneal dialysis patients and assessed its relations with fasting blood glucose, homeostasis model assessment of insulin resistance (HOMA-IR), and glucose exposure from peritoneal dialysis fluid.

RESULTS

Twenty-four patients (48%) had no coronary calcification. When patients were grouped according to the presence or absence of calcification, patients with calcification were mostly men and had higher burden of cardiovascular disease history, vitamin D dose intake, serum calcium, total glucose exposure from dialysis solution, and lower total weekly Kt/Vurea. In multivariate analysis, dialysate glucose exposure was an independent predictor of coronary artery calcification score, besides serum calcium and Kt/Vurea.

CONCLUSION

These data suggest that high glucose exposure from dialysis solution, which is potentially correctable, is a risk factor for vascular calcification in non-diabetic PD patients.

Peritoneal dialysis in diabetics: there is room for more

End stage renal disease diabetic patients suffer from worse clinical outcomes under dialysis-independently of modality. Peritoneal dialysis offers them the advantages of home therapy while sparing their frail vascular capital and preserving residual renal function. Other benefits and potential risks deserve discussion. Predialysis intervention with early nephrology referral, patient education, and multidisciplinary support are recommended. Skilled and updated peritoneal dialysis protocols must be prescribed to assure better survival. Optimized volume control, glucose-sparing peritoneal dialysis regimens, and elective use of icodextrin are key therapy strategies. Nutritional evaluation and support, preferential use of low-glucose degradation products solutions, and prescription of renin-angiotensin-aldosterone system acting drugs should also be part of the panel to improve diabetic care under peritoneal dialysis.