Electrochemical Skin Conductance by Sudoscan in Non-Dialysis Chronic Kidney Disease Patients

BACKGROUND

Peripheral neuropathy is prevalent among patients with chronic kidney disease (CKD). Sudoscan non-invasively detects polyneuropathy by measuring electrochemical skin conductance (ESC). We conducted a study on sudomotor function in CKD patients across various stages based on their estimated glomerular filtration rate (eGFR).

METHODS

In this cross-sectional study of 700 CKD patients, all underwent Sudoscan. Pathological ESC was defined as hands < 40 μS or feet < 50 μS. Clinical neuropathy scores including Michigan Neuropathy Screening Instrument (MNSI) and Douleur Neuropathique en 4 questionnaire (DN4) were obtained.

RESULTS

Among participants, 344 had diabetes and 356 did not. Hands and feet ESC decreased with CKD progression (median (IQR) in stage 1-2, 3, 4-5: 54.0 (39.0-68.0), 45.5 (30.0-63.0), 41.8 (26.5-60.5), p trend < 0.001; 64.5 (53.5-74.0), 60.5 (43.0-72.5), 55.0 (39.0-69.8), p trend < 0.001). Pathological hands and feet ESC increased in later CKD stages (stage 1-2, 3, 4-5: 26.6%, 40.9%, 45.7%, p trend < 0.001; 21.7%, 34.0%, 40.6%, p trend < 0.001). Positive hands and feet ESC-eGFR correlation existed irrespective of diabetes. Diabetic patients had lower hands and feet ESC than non-diabetics as CKD progressed. However, multivariate regression found no significant ESC-eGFR association. Sudoscan correlated with clinical neuropathy scores.

CONCLUSION

Pathological sudomotor function was common in non-dialysis CKD stages 4-5. Diabetic patients had worse function. Sudomotor dysfunction progressed with renal disease but eGFR was not an independent risk factor.

Urinary Klotho Excretion: A Key Regulator of Sodium Homeostasis in Chronic Kidney Disease Stage 2-4

BACKGROUND Soluble alpha-klotho (klotho) is considered an important regulator of mineral homeostasis in patients with chronic kidney disease (CKD). Since the mineral transport proteins are located on the apical membrane of renal tubular cells, we hypothesized that urine klotho may also be involved in their homeostasis. We aimed to investigate the associations between serum and urine klotho and their impacts on mineral homeostasis in patients with stage 2 to 4 CKD. MATERIAL AND METHODS Serum, spot urine, and 24-h urine of klotho were measured by using enzyme-linked immunosorbent assay. Fractional excretion of sodium, potassium, calcium, phosphate, magnesium, and klotho were calculated. RESULTS A total of 53 patients with CKD stages 2 to 4 were enrolled in this cross-sectional study. The mean age was 71.1±10.5 years, and 68% were men. Linear regression analysis showed that serum log-transformed klotho was negatively associated with log-transformed fractional excretion of klotho (log-FEKlotho) (ß=-0.085, P=0.02), showing that urinary klotho excretion could negatively regulate serum klotho levels. Moreover, our multivariate stepwise regression showed log-fractional excretion of sodium was positively associated with log-FEKlotho (ß=0.138, P=0.032). This implied urinary klotho excretion positively regulated urinary sodium excretion. CONCLUSIONS Our study showed that urine klotho excretion resulted in decreased serum klotho levels and enhanced urinary sodium excretion in patients with CKD stages 2 to 4. In addition to serum klotho, we found, for the first time, that urine klotho also played a significant role in sodium homeostasis.

Phosphate burden induces vascular calcification through a NLRP3-caspase-1-mediated pyroptotic pathway

AIMS

The aim of this study is to clarify the role of NLRP3 inflammasome in phosphate burden-induced vascular smooth muscle cell (VSMC) calcification.

MAIN METHODS

VSMC calcification was induced using a high concentration of inorganic phosphate. After pharmacological inhibition or genetic silencing of the NLRP3 inflammasome, pyroptosis, or potassium efflux, the cells were examined by RT-qPCR, immunofluorescence, and western blotting to identify the NLRP3-mediated pathway for VSMC calcification.

KEY FINDINGS

Calcified VSMCs with α-smooth muscle actin (α-SMA) disarray presented features of pyroptosis, including caspase-1 maturation, cleaved gasdermin D (GSDMD), and a high supernatant level of lactate dehydrogenase A. Pharmacological inhibitions of caspase-1 and pyroptosis attenuated VSMC calcification, whereas interleukin-1β receptor antagonism did not. Unlike canonical NLRP3 activation, osteogenic VSMCs did not upregulate NLRP3 expression. However, NLRP3 genetic silencing or inhibitions, which targets different domains of the NLRP3 protein, could ameliorate VSMC calcification by aborting caspase-1 and GSDMD activation. Furthermore, potassium efflux through the inward-rectifier potassium channel, and not through the P2X7 receptor, triggered NLRP3 inflammasome activation and VSMC calcification.

SIGNIFICANCE

In the present study, we identified a potassium efflux-triggered NLRP3-caspase-1-mediated pyroptotic pathway for VSMC calcification that is unique and different from the canonical NLRP3 inflammasome activation. Therefore, targeting this pathway may serve as a novel therapeutic strategy for vascular calcification.

A New Predictive Equation for Estimating Serum Ionized Calcium Levels in Patients on Chronic Hemodialysis

BACKGROUND Circulating calcium mainly carries out its physiologic function in its ionized form (iCa). Clinically, iCa is usually estimated by multiplying the total calcium (TCa) level by 0.5 in the general population, but this method is not accurate when applied to patients on long-term hemodialysis (CHD). Accordingly, this study aimed to develop a predictive function for iCa in patients on CHD by incorporating TCa and other additional variables. MATERIAL AND METHODS This was a retrospective cross-sectional study consisting of 2 cross-sectional datasets: a derivation set including 469 CHD patients in June 2019, and a validation set including 446 CHD patients in September 2019. The derivation set's data were analyzed using the stepwise model selection of machine learning with 10-fold cross-validation to develop a predictive function for iCa. This predictive function was then applied to the validation set's data, and the predictive function's estimated iCa was compared with the actual laboratory iCa by using the paired-samples t test and intraclass correlation coefficient. RESULTS After analyzing the routine laboratory data parameters of patients in the derivation set, the following 5 variables were included in the predictive function of iCa: blood urea nitrogen, creatinine, phosphate, TCa, and albumin. This predictive function was applied to the validation set to yield an estimated iCa level that was not significantly different from the laboratory-measured iCa level of the validation dataset (P=0.676) with an excellent ICC of 0.905. CONCLUSIONS We developed a new predictive function that accurately measures the iCa in patients on CHD by using routine laboratory data.

Impact of Pre-Transplant Parathyroidectomy on Graft Survival: A Comparative Study of Renal Transplant Patients (2005-2015)

BACKGROUND Hyperparathyroidism poses significant risks for patients prior to kidney transplantation. However, the outcomes of patients who undergo parathyroidectomy before renal transplantation compared to those without such a procedure remain uncertain. This real-world data study aimed to examine the clinical outcomes of both patient groups. MATERIAL AND METHODS Using the Taiwan National Health Insurance Research Database, we conducted a retrospective cohort study on patients who underwent renal transplantation between January 2005 and December 2015. The patients were divided into two groups: a case group (n=294) with parathyroidectomy and a control group (n=588) without the need for parathyroidectomy before kidney transplantation. The groups were matched based on age, sex, dialysis vintage, and baseline characteristics at a 1:2 ratio. Hazard ratios (HR) were estimated using the Cox regression model. The main outcomes assessed were graft failure, mortality, and major adverse cardiovascular events (MACE) recorded until December 2019. RESULTS During a mean follow-up period of 6 years, a significant difference was observed in graft failure (HR 1.40; 95% confidence interval 1.10-1.79, p=0.007) between the two groups. After further adjustment, graft failure remained significant (HR 1.52; 95% CI 1.07-2.15, p=0.019). Additionally, machine learning-based feature selection identified the importance of parathyroidectomy (ranked 9 out of 11) before kidney transplantation in predicting subsequent graft failure. CONCLUSIONS Our study demonstrates that severe hyperparathyroidism requiring parathyroidectomy before kidney transplantation may contribute to poor post-transplant graft outcomes compared to patients who do not require parathyroidectomy.

Protective Effect of BCG and Neutrophil-to-Lymphocyte Ratio on Latent Tuberculosis in End Stage Renal Disease

INTRODUCTION

Bacillus Calmette-Guérin (BCG) vaccination has been reported to be protective against latent tuberculosis infection (LTBI) in the general population. The aim of this study was to investigate the protective effect of BCG vaccination against LTBI in adult patients with end-stage renal disease (ESRD) and renal transplants.

METHODS

Patients aged ≥ 20 years with ESRD who received hemodialysis (HD), peritoneal dialysis (PD) or kidney transplant were enrolled from January 2012 to December 2019 at a medical center and a regional hemodialysis center. Patients with active tuberculosis (TB), previously treated TB, active immunosuppressant therapy or human immunodeficiency virus infection were excluded. LTBI status was determined by QuantiFERON-TB Gold In-tube (QFT-GIT).

RESULTS

After the exclusion of indeterminate results of QFT-GIT, 517 participants were enrolled and 97 (18.8%) were identified as having LTBI. Participants with LTBI were older (55.1 ± 11.4 vs. 48.5 ± 14.6 years, p < 0.001) and had a significantly higher proportion receiving HD than those without LTBI (70.1% vs. 56.7%, p = 0.001). The percentage with BCG scars was higher in the non-LTBI group than in the LTBI group (94.8% vs. 81.4%, p < 0.001), whereas the neutrophil-to-lymphocyte ratio (NLR) (≥ 2.68) was significantly higher in the LTBI group (62.8% vs. 45.5%, p = 0.02). By multivariate logistic regression analysis, presence of BCG scar and high NLR were independent protective factors against LTBI [adjusted OR: 0.19 (0.063-0.58, p = 0.001) and 0.50 (0.28-0.89, p = 0.02)].

CONCLUSION

The prevalence of LTBI was as high as 18.8% in patients with end-stage kidney disease or kidney transplant. BCG vaccination and high NLR might have protective effects against LTBI in patients with renal failure or transplant.

High intact fibroblast growth factor 23 levels associated with low hemoglobin levels in patients on chronic hemodialysis

Introduction

A negative association between C-terminal fibroblast growth factor 23 (cFGF23) and hemoglobin (Hb) levels has been reported in patients with predialysis chronic kidney disease. In dialysis patients, the dominant form of serum FGF23 is intact FGF23 (iFGF23); however, its association with the Hb level remains unclear. Therefore, simultaneously monitoring iFGF23 and cFGF23 levels is crucial. In this study, we investigated the associations between both forms of FGF23 (iFGF23 and cFGF23) and renal anemia in chronic hemodialysis (CHD) patients.

Methods

We included 166 CHD patients from two hospitals in this cross-sectional, observational study. The primary predictors were serum iFGF23, cFGF23, and iFGF23/cFGF23 levels. The main outcome was the Hb level.

Results

Among the CHD patients included, 60.8% were men with a mean age of 59.4 ± 12.7 years. In the crude analysis, iFGF23 and iFGF23/cFGF23 levels showed a significant negative association (−0.27, p = 0.004 and −0.22, p = 0.034, respectively) with the Hb level. Even after adjusting for multiple variables (a parsimonious model), every increment of natural log transformation by 1 for (ln)iFGF23 and ln(iFGF23/cFGF23) levels showed a negative correlation with the Hb level (estimate: −0.27 [95%CI: −0.44, −0.10, p = 0.001]; −0.19 [95%CI: −0.37, −0.01, p = 0.042], respectively), whereas both were positively associated with erythropoietin-stimulating agent (ESA) hyporesponsiveness (odds ratio [OR]: [95%CI: 2.30, 1.26–4.17], p = 0.006; 1.95 [95%CI: 1.08–3.50], p = 0.025). Moreover, these abovementioned associations were more dominant in patients with diabetes who used angiotensin receptor blockers.

Discussion

In conclusion, a negative association between serum iFGF23 or iFGF23/cFGF23 level and the Hb level was observed in our CHD patients. Meanwhile, a higher iFGF23 or iFGF23/cFGF23 level may predispose patients to ESA hyporesponsiveness.

Evaluation of the Impact of Remote Monitoring Using the Sharesource Connectivity Platform on Adherence to Automated Peritoneal Dialysis in 51 Patients

BACKGROUND This study from a single center in Taiwan aimed to evaluate the impact of remote patient monitoring (RPM) using the Sharesource connectivity platform on adherence to automated peritoneal dialysis (APD) in 51 patients. MATERIAL AND METHODS We analyzed data on 51 patients with end-stage renal disease (ESRD) under APD. They were treated with a traditional APD machine HomeChoice (phase 1), changed to new APD machine HomeChoice Claria for 12 weeks (phase 2), then connected to the Sharesource platform for another 12 weeks (phase 3), and were followed up for 1 year. The non-adherence rate was compared between the 3 phases. The secondary outcomes included peritonitis rate, hospitalization rate, and hospitalization days, 1 year before and after receiving a new APD machine. Patients were subdivided into good and poor adherence (>1 episode of non-adherence in phase 1) groups for further analysis. RESULTS The average non-adherence rates were 10.5%, 5.1%, and 4.9% in phases 1, 2, and 3, respectively, although differences were not significant. Serum potassium (P<0.0001) and C-reactive protein (CRP) (P=0.026) levels significantly decreased in phase 3. The 1-year peritonitis rate, hospitalization rate, and number of days of hospitalization showed no significant changes. Subgroup analysis revealed that the non-adherence rate in the poor adherence group decreased from 48.4% in phase 1 to 14.2% and 12.4% in phases 2 and 3, respectively (P=0.007). CONCLUSIONS Remoting monitoring using the Sharesource connectivity platform increased dialysis adherence in APD treatment, especially in patients with poor adherence. Serum potassium level and inflammation status were also improved by this system.

Serum Intact Fibroblast Growth Factor 23 Levels Are Negatively Associated with Bone Mineral Density in Chronic Hemodialysis Patients

(1) Background: Fibroblast growth factor 23 (FGF23) is predominantly secreted from bone and plays an important role in mineral balance in chronic kidney disease. However, the relationship between FGF23 and bone mineral density (BMD) in chronic hemodialysis (CHD) patients remains unclear. (2) Methods: This was a cross-sectional observational study that involved 43 stable outpatients on CHD. A linear regression model was used to determine risk factors for BMD. Measurements included serum hemoglobin, intact FGF23 (iFGF23), C-terminal FGF23 (cFGF23), sclerostin, Dickkopf-1, α-klotho, 1,25-hydroxyvitamin D, intact parathyroid hormone levels and dialysis profiles. (3) Results: Study participants had a mean age of 59.4 ± 12.3 years, and 65% were male. In the multivariable analysis, cFGF23 levels showed no significant associations with the BMD of the lumbar spine (p = 0.387) nor that of the femoral head (p = 0.430). However, iFGF23 levels showed a significant negative association with the BMD of the lumbar spine (p = 0.015) and that of the femoral neck (p = 0.037). (4) Conclusions: Among patients on CHD, higher serum iFGF23 levels, but not serum cFGF23 levels, were associated with lower BMD values of the lumbar spine and femoral neck. However, further research is required to validate our findings.

All-Cause Standardized Mortality Ratio in Hemodialysis and Peritoneal Dialysis Patients: A Nationwide Population-Based Cohort Study

Patients with end-stage renal disease (ESRD) are at a higher mortality risk compared with the general population. Previous studies have described a relationship between mortality and patients with ESRD, but the data on standardized mortality ratio (SMR) corresponding to different causes of death in patients undergoing hemodialysis (HD) and peritoneal dialysis (PD) are limited. This study was designed as a nationwide population-based retrospective cohort study. Incident dialysis patients between January 2000 and December 2015 in Taiwan were included. Using data acquired from the Taiwan Death Registry, SMR values were calculated and compared with the overall survival. The results showed there were a total of 128,966 patients enrolled, including 117,376 incident HD patients and 11,590 incident PD patients. It was found that 75,297 patients (58.4%) died during the period of 2000-2017. The overall SMR was 5.21. The neoplasms SMR was 2.11; the endocrine, nutritional, metabolic, and immunity disorders SMR was 13.53; the circulatory system SMR was 4.31; the respiratory system SMR was 2.59; the digestive system SMR was 6.1; and the genitourinary system SMR was 27.22. Therefore, more attention should be paid to these diseases in clinical care.

The use of a low-flux hemo-dialyzer is associated with impaired platelet aggregation in patients undergoing chronic hemodialysis

In patients with chronic hemodialysis (HD), both abnormal thrombotic and bleeding events are commonly observed. Uremic platelet dysfunction is one of the important attributing factors. Moreover, HD may also result in aggregation dysfunction of platelets during the therapeutic procedure. However, how the HD process affects platelet and coagulation function is unknown and dialyzer membrane flux could have an impact on it. We aimed to compare the impacts of low-flux and high-flux HD on the platelet function of patients undergoing chronic HD. This was a cross-sectional study conducted in the HD unit of E-Da hospital in Taiwan. A total of 78 patients with maintenance HD three times per week for more than one year, including 40 with high- and 38 with low-flux hemodialysis, were recruited. Their platelet functions were evaluated using an in vitro platelet function analyzer (PFA-100) before and after the HD session. Of the 78 patients undergoing HD, 60 (76%) had prolonged pre-dialysis collagen/epinephrine (CEPI) and collagen/adenosine diphosphate closure times. Those receiving low-flux dialyzer had a significant increase in CEPI closure time (pre-dialysis 212.3 ± 62.1 seconds. post-dialysis 241.5 ± 64.3 seconds, P = .01), but not collagen/adenosine diphosphate closure time, after HD. After adjusting confounding factors, only the low-flux dialyzer demonstrated an independent association with the prolonged CEPI closure time after HD therapy (odds ratio = 23.31, 95% CI: 1.94-280.61, P = .01). We observed that impaired platelet aggregation is prevalent in patients undergoing chronic HD. Therefore, the use of low-flux dialyzers may further worsen platelet aggregation after dialysis. Patients with uremic bleeding diathesis should take precautions. We suggest that further studies using flow cytometry should be conducted to explore the mechanism of dialysis flux and platelet activity during HD.

The Protective Effects of Lipid-Lowering Agents on Cardiovascular Disease and Mortality in Maintenance Dialysis Patients: Propensity Score Analysis of a Population-Based Cohort Study

Lipid-lowering agents display limited benefits on cardiovascular diseases and mortality in patients undergoing dialysis. Therefore, they are not routinely recommended for dialysis patients. The aim of this study was to assess the effects of lipid-lowering agents on clinical outcomes in dialysis patients on the basis of real-world evidence. This research used Taiwan’s National Health Insurance Research Database to identify dialysis patients from January 2009 to December 2015; patients were then categorized into a case group treated with lipid-lowering agents (n = 3,933) and a control group without lipid-lowering agents (n = 24,267). Patients were matched by age, sex, and comorbidities in a 1:1 ratio. This study used the Cox regression model to estimate the hazard ratios (HRs) for mortality and major adverse cardiovascular events (MACEs) for events recorded until December 2017. During a mean follow-up period of approximately 3.1 years, 1726 [43.9%, incidence 0.123/person-year (PY)] deaths and 598 (15.2%, incidence 0.047/PY) MACEs occurred in the case group and 2031 (51.6%, incidence 0.153/PY) deaths and 649 (16.5% incidence 0.055/PY) MACEs occurred in the control group. In the multivariable analysis of the Cox regression model, lipid-lowering agent users showed a significantly lower risk of death [HR: 0.75; 95% confidence interval (CI): 0.70–0.80] and MACEs (HR: 0.88; 95% CI: 0.78–0.98) than lipid-lowering agent non-users. Moreover, the survival benefit of lipid-lowering agents was significant across most subgroups. Dialysis patients treated with lipid-lowering agents display a 25 and 12% reduction in their risk of mortality and MACEs, respectively. Therefore, lipid-lowering agents might be considered when treating dialysis patients with hyperlipidemia.

The Association of Urinary Sclerostin and Renal Magnesium Handling in Type 2 Diabetic Patients with Chronic Kidney Disease

INTRODUCTION

Sclerostin could enhance renal excretion of calcium (Ca) and phosphate (P). The association between sclerostin and magnesium (Mg) has not yet discovered. In patients with type 2 diabetes mellitus (T2DM) or chronic kidney disease (CKD), higher serum sclerostin and altered renal excretion of Ca, P, and Mg were detected. Therefore, we tried to evaluate if there was any association between sclerostin and fractional excretion of Ca, P, and Mg (FeCa, FeP, and FeMg) in T2DM with CKD.

METHODS

In this prospective cohort study, 43 T2DM patients without CKD or with CKD stage 1-5 were enrolled. Values of parameters, including serum and urine sclerostin, were collected at baseline and 6 months later. For baseline data, the Mann-Whitney U test, χ2 test, or Spearman's correlation were used. For multivariate repeated measurement analysis, generalized estimating equation (GEE) model was utilized.

RESULTS

Patients with lower estimated glomerular filtration rate had higher serum sclerostin, FeP, FeMg, and lower FeCa. By correlation analysis, serum sclerostin was negatively associated with FeCa (p = 0.02) and positively associated with FeP (p = 0.002). The urine sclerostin to creatinine ratio (Uscl/Ucre) was positively correlated with FeP (p = 0.007) and FeMg (p = 0.005). After multivariate analyses by GEE model, serum sclerostin was still inversely associated with FeCa, while Uscl/Ucre was significantly associated with FeMg. On the other hand, FeP lost its associations with serum sclerostin or Uscl/Ucre.

CONCLUSION

In our study population of T2DM patients with or without CKD, the inverse correlation between serum sclerostin and FeCa could not be explained by the calciuric effect of sclerostin. In addition, a newly discovered positive association between urinary sclerostin and FeMg indicated a possible role of urinary sclerostin in regulating renal Mg handling especially over distal convoluted tubules.

Effects of ketoanalogues on skeletal muscle mass in patients with advanced chronic kidney disease: real-world evidence

OBJECTIVE

Ketoanalogue (KA) supplementation in patients with chronic kidney disease (CKD) on a restricted protein diet has been shown to maintain their nutritional status in clinical trials. However, a gap existed between the findings of the clinical trials and the real-world practice. The aim of this prospective observational study was to evaluate the KA effect on skeletal muscle mass in patients with stage 4-5 CKD.

METHODS

Among 170 patients with CKD screened, 148 were recruited. Patients were defined as KA or non-KA users. During a 12-mo follow-up, skeletal muscle and body fat mass were measured via bioelectrical impedance analysis at baseline, 6 mo (n = 108), and 12 mo (n = 85).

RESULTS

Among the patients (mean age, 66.5 ± 12.9 y), KA users tended to maintain skeletal muscle and body fat mass, whereas non-KA users had a significantly reduced muscle mass (P = 0.011) and body fat gain (P = 0.004). Stratified by median age, in patients ≥68 y of age, non-KA users yielded the most significant muscle mass reduction and fat mass gain, whereas KA users revealed no changes in skeletal muscle and fat mass.

CONCLUSION

In real-world practice, we concluded that KA supplementation favorably prevents skeletal muscle mass loss and fat mass gain in elderly patients with stage 4-5 CKD.

Novel Application of Magnetite Nanoparticle-Mediated Vitamin D3 Delivery for Peritoneal Dialysis-Related Peritoneal Damage

PURPOSE

Vitamin D3 is useful for the treatment of peritoneal dialysis (PD)-related peritoneal damage, but its side effects, such as hypercalcemia and vascular calcification, limit its applicability. Thus, we developed vitamin D-loaded magnetic nanoparticles (MNPs) and determined their therapeutic efficacy and side effects in vivo.

MATERIALS AND METHODS

Alginate-modified MNPs were combined with 1α, 25 (OH)2D3 to generate vitamin D-loaded nanoparticles. The particles were conjugated with an antibody against peritoneum-glycoprotein M6A (GPM6A). The particles' ability to target the peritoneum was examined following intraperitoneal administration to mice and by monitoring their bio-distribution. We also established a PD animal model to determine the therapeutic and side effects of vitamin D-loaded MNPs in vivo.

RESULTS

Vitamin D-loaded MNPs targeted the peritoneum better than vitamin D3, and had the same therapeutic effect as vitamin D3 in ameliorating peritoneal fibrosis and functional deterioration in a PD animal model. Most importantly, the particles reduced the side effects of vitamin D3, such as hypercalcemia and body weight loss, in mice.

CONCLUSION

Vitamin D-loaded MNPs could be an ideal future therapeutic option to treat PD-related peritoneal damage.

Indoxyl Sulfate Mediates the Low Inducibility of the NLRP3 Inflammasome in Hemodialysis Patients

The NLRP3 inflammasome is responsible for the maturation of caspase-1 and interleukin-1β (IL-1β). Despite the study about basal activity of the NLRP3 inflammasome in hemodialysis (HD) patients, little is known about its inducibility in the milieu of uremia. Peripheral blood mononuclear cells (PBMCs) isolated from 11 HD patients and 14 volunteers without a history of chronic kidney disease, as well as macrophages with or without the uremic toxin indoxyl sulfate (IS) pretreatment, underwent canonical NLRP3 inflammasome induction. Despite the high plasma levels of IL-1β in HD patients, caspase-1 and IL-1β in the PBMCs of HD patients remained predominantly immature and were not secreted in response to the canonical stimulus. In addition, while IS alone facilitated the inflammasome-independent secretion of IL-1β from macrophages, IS exposure before induction reduced the inducibility of the NLRP3 inflammasome, characterized by insufficient maturation of caspase-1. The low expression of inflammasome components, which was observed in both IS-pretreated cells and the PBMCs of HD patients, was probably responsible for the low inducibility.

Association of Serum Indoxyl Sulfate Levels with Skeletal Muscle Mass and Strength in Chronic Hemodialysis Patients: A 2-year Longitudinal Analysis

Sarcopenia is highly prevalent in patients undergoing chronic hemodialysis (HD). This study investigated the relationship among serum indoxyl sulfate (IS) levels, muscle mass, and strength in HD patients. A total of 108 HD patients were enrolled. Skeletal muscle mass and handgrip strength (HGS) were assessed, using bioimpedance analysis and a hand-held dynamometer, respectively. Skeletal muscle index (SMI) was defined as skeletal muscle mass/height² (kg/m²). Serum IS, p-cresol sulfate (PCS), and trimethylamine N-oxide (TMAO) levels were determined using liquid chromatography-mass spectrometry. Patients were classified into two groups based on median serum IS values. HGS measurement was repeated after 2 years. Patients in the high IS group had longer HD duration and higher serum TMAO levels than those in the low IS group. Log-normalized IS level was negatively correlated with SMI (r = - 0.227; p = 0.018), but PCS and TMAO levels were not. Among 78 patients who completed 2-year follow-up, those in the high IS group (n = 41) showed greater absolute (- 2.48 kg versus - 0.25 kg, p = 0.035) and relative HGS loss (- 9.1% versus 1.4%, p = 0.036) than those in the low IS group, after adjustment for potential confounders. Indoxyl sulfate (IS) may play a significant role in uremic sarcopenia. Further large-scale studies are needed to confirm our preliminary findings.

Frequent transfusion and specific HLA-DRB1 alleles correlate independently with Miltenberger blood group alloimmunization in dialysis patients

Anti-"Mi^a " is the most frequent irregular RBC antibody in Taiwan due to high prevalence of Miltenberger antigens. Dialysis patients, a special patient group that needs frequent transfusions of RBCs, may have the greatest risk for developing anti-"Mi^a " antibodies. The aim of this study was to investigate the association between specific HLA-DRB1 alleles and Mi alloimmunization among dialysis patients. A cohort of 267 maintenance dialysis patients who had ever received at least one RBCs transfusion was enrolled. Anti-"Mi^a " was identified in patients' serum using the manual polybrene technique and HLA-DRB1 genotyping was carried out using polymerase chain reaction and sequence-specific oligonucleotide probe nonradioactive hybridization. Twenty-one (7.9%) of patients had positive anti-"Mi^a " tests and had received significantly more units of RBC transfusions than those without anti-"Mi^a " antibodies (11.3 ± 14.5 U vs 4.5 ± 10.1 U, P = .005). DRB1*04, *07, and *09 alleles were also more prevalent in patients with anti-"Mi^a " compared to those without Mi III alloimmunization. The multivariate logistic regression analysis showed that the number of RBC transfusions and the presence of DRB1*04, *07, and *09 phenotypes correlated independently with Mi III immunization (Odds ratios [OR] 1.05 (P = .001) for each unit of RBCs transfused; ORs 4.80 (P = .006), 12.29 (P = .005), and 5.42 (P = .003) for presence of DRB1*04, *07, and *09, respectively). This study is the first to demonstrate markedly high prevalence of Mi III alloimmunization in dialysis patients of Taiwan. Extending Mi III matching for RBC transfusions in susceptible dialysis patients may help to reduce the risk of Mi III alloimmunization in this patient population.

Risk of Serious Falls Between Hemodialysis and Peritoneal Dialysis Patients: A Nationwide Population-based Cohort Study

The association between serious falls and dialysis modality [hemodialysis (HD) and peritoneal dialysis (PD)] is unclear. A nationwide population-based retrospective cohort study with 127,823 end-stage renal disease patients aged over 18 years was conducted with the unmatched cohort of 101,304 HD and 7,584 PD patients retrieved from Taiwan's National Health Insurance Research Database during 2000-2013. A total of 7,584 HD and 7,584 PD patients matched at 1:1 ratio by propensity score were enrolled to the study. Serious falls were defined by the diagnostic codes, E code, and image studies. Cox regression model and competing-risk model were used for statistical analysis. HD patients were older and had more comorbidities at baseline than PD patients. After matching and adjustment, HD patients had a higher risk of serious falls than PD patients [sHR 1.27 (95% CI 1.06-1.52)]. Females, elders, a history of falls before dialysis, comorbidity with stroke or visual problems, using diuretics, α-blockers, and mydriatics were associated with higher risks of serious falls among dialysis patients. The risk of serious falls was higher in HD patients than PD patients. Health professionals should create age-friendly environments, reduce unnecessary medications, and raise patients' awareness of falls in daily life.

The Clinical Implication of Vitamin D Nanomedicine for Peritoneal Dialysis-Related Peritoneal Damage

PURPOSE

Vitamin D is a novel potential therapeutic agent for peritoneal dialysis (PD)-related peritoneal fibrosis, but it can induce hypercalcemia and vascular calcification, which limits its applicability. In this study, we create nanotechnology-based drug delivery systems to investigate its therapeutics and side effects.

MATERIALS AND METHODS

1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N- [amino-(polyethylene glycol)2000] (DSPE-PEG) and L-α-phosphatidylcholine (PC), which packages with 1α,25(OH)2D3, were used to construct vitamin D nanoliposomes. To confirm the function and safety of vitamin D nanoliposomes, peritoneal mesothelial cells were treated with TGF-β1 and the reverse was attempted using vitamin D nanoliposomes. Antibodies (Ab) against the peritoneum-glycoprotein M6A (GPM6A) Ab were conjugated with vitamin D nanoliposomes. These particles were implanted into mice by intraperitoneal injection and the animals were monitored for the distribution and side effects induced by vitamin D.

RESULTS

Vitamin D nanoliposomes were taken up by the mesothelial cells over time without cell toxicity and it also provided the same therapeutic effect in vitro. In vivo study, fluorescent imaging showed vitamin D nanoliposomes allow specific peritoneum target effect and also ameliorate vitamin D side effect.

CONCLUSION

Nanoliposomes vitamin D delivery systems for the prevention of PD-related peritoneal damage may be a potential clinical strategy in the future.

Impact of sarcopenia and its diagnostic criteria on hospitalization and mortality in chronic hemodialysis patients: A 3-year longitudinal study

BACKGROUND/PURPOSE

Sarcopenia is prevalent in chronic hemodialysis patients. This prospective cohort study evaluated the impact of sarcopenia and its diagnostic criteria on hospitalization and mortality in 126 chronic hemodialysis patients.

METHODS

Skeletal muscle mass, handgrip strength (HGS), gait speed, and blood parameters were assessed. Sarcopenia was evaluated using the criteria of the European Working Group on Sarcopenia in Older People and the Taiwanese criteria for Sarcopenia. Muscle quality was defined as HGS divided by mid-arm muscle circumference.

RESULTS

Prevalences of uremic sarcopenia were 8.7% and 13.5% according to Taiwanese and European criteria, respectively. Low HGS and gait speed were much more prevalent than low muscle mass. Within 3 years, 79 (62.7%) patients were hospitalized and 26 (20.6%) died. Low HGS and slow gait speed were associated with hospitalization and mortality, while sarcopenia was associated with mortality but not with hospitalization. Notably, in our patients without sarcopenia, close associations between increased hospitalization and mortality risk with low HGS and slow gait speed remained unchanged. In Cox proportional hazard analysis, muscle quality [hazard ratio (HR) = 0.42, 95% confidence interval (CI) = 0.19-0.93, p = 0.032] and serum creatinine (HR = 0.82, 95% CI = 0.71-0.95, p = 0.009) were independently associated with composite outcome of hospitalization or death.

CONCLUSION

Muscle functionality and quality can predict hospitalization and overall survival in chronic hemodialysis patients, better than muscle mass.

Serum sclerostin levels are positively related to bone mineral density in peritoneal dialysis patients: a cross-sectional study

Background

Sclerostin, an antagonist of the Wingless-type mouse mammary tumor virus integration site (Wnt) pathway that regulates bone metabolism, is a potential contributor of chronic kidney disease (CKD)–mineral and bone disorder (MBD), which has various forms of presentation, from osteoporosis to vascular calcification. The positive association of sclerostin with bone mineral density (BMD) has been demonstrated in CKD and hemodialysis (HD) patients but not in peritoneal dialysis (PD) patients. This study assessed the association between sclerostin and BMD in PD patients.

Methods

Eighty-nine PD patients were enrolled; their sera were collected for measurement of sclerostin and other CKD–MBD-related markers. BMD was also assessed simultaneously. We examined the relationship between sclerostin and each parameter through Spearman correlation analysis and by comparing group data between patients with above- and below-median sclerostin levels. Univariate and multiple logistic regression models were employed to define the most predictive of sclerostin levels in the above-median category.

Results

Bivariate analysis revealed that sclerostin was correlated with spine BMD (r = 0.271, P = 0.011), spine BMD T-score (r = 0.274, P = 0.010), spine BMD Z-score (r = 0.237, P = 0.027), and intact parathyroid hormone (PTH; r = − 0.357, P < 0.001) after adjustments for age and sex. High BMD, old age, male sex, increased weight and height, diabetes, and high osteocalcin and uric acid levels were observed in patients with high serum sclerostin levels and an inverse relation was noticed between PTH and sclerostin. Univariate logistic regression analysis demonstrated that BMD is positively correlated with above-median sclerostin levels (odds ratio [OR] = 65.61, P = 0.002); the correlation was retained even after multivariate adjustment (OR = 121.5, P = 0.007).

Conclusions

For the first time, this study demonstrated a positive association between serum sclerostin levels and BMD in the PD population.

Exercise Alleviates Osteoporosis in Rats with Mild Chronic Kidney Disease by Decreasing Sclerostin Production

Chronic kidney disease–mineral bone disorder (CKD–MBD), comprising mineral, hormonal, and bone metabolic imbalance, is a major CKD-related issue; it causes osteoporosis prevalence in CKD patients. Osteocyte-derived sclerostin inhibits the osteogenic Wnt/β-catenin signaling pathway; its levels rise when kidney function declines. Exercise modulates the physiological functions of osteocytes, potentially altering sclerostin production. It may aid bone and mineral electrolyte homeostasis in CKD. Mild CKD was induced in rats by partial nephrectomy. They were divided into: sham (no CKD), CKD, and CKD + exercise (8 weeks of treadmill running) groups. Micro-CT scanning demonstrated that the CKD + exercise-group rats had a higher bone mineral density (BMD) of the spine and femoral metaphysis and higher femoral trabecular bone volume than the CKD-group rats. Bone formation rates were not significantly different. The CKD + exercise-group rats had lower serum sclerostin (157.1 ± 21.1 vs 309 ± 38.1 pg/mL, p < 0.05) and CTX-1 (bone resorption marker) levels. Immunohistochemistry revealed higher tibial β-catenin concentrations in the CKD + exercise-group rats. Serum FGF-23, intact parathyroid hormone (iPTH), alkaline phosphatase (ALP), calcium, and phosphate levels showed no significant differences between these groups. Thus, exercise improves BMD and bone microstructure in mild CKD by inhibiting sclerostin production, but does not alter serum minerals.

Angiotensin II receptor blockade is associated with preserved muscle strength in chronic hemodialysis patients

BACKGROUND

Sarcopenia, defined as low muscle mass and strength, is highly prevalent in patients undergoing chronic hemodialysis (HD). However, muscle function and muscle mass do not share the same clinical relevance. In fact, muscle strength was more closely associated with the risk of mortality in chronic HD patients than was muscle mass. Therefore, to identify the risk factors of muscle weakness is vital. Angiotensin II overexpression had been recognized to impair skeletal muscle strength. Accordingly, angiotensin II receptor blockers (ARBs) potentially possess a muscle protective effect. This cross-sectional study aimed to identify the factors associated with low muscle strength and to explore the relationship between ARB use and muscle strength in chronic HD patients.

METHODS

A total of 120 chronic HD patients, aged 63.3 ± 13.2 years, were included in this study. Basic characteristics, handgrip strength (HGS), body composition, and nutritional status were assessed, and blood samples for biochemical tests were obtained. We divided these participants into normal- and low HGS groups according to the consensus of the European Working Group on Sarcopenia in Older People (EWGSOP).

RESULTS

We observed that 78 (65.0%) patients had low HGS. In our cohort, we found that height (r = 0.653; P <  0.001), weight (r = 0.496; P <  0.001), body mass index (r = 0.215; P = 0.020), skeletal muscle index (r = 0.562; P <  0.001), albumin (r = 0.197; P = 0.032), and serum creatinine (r = 0.544; P <  0.001) were positively and age (r = - 0.506; P <  0.001), subjective global assessment (SGA) score (r = - 0.392; P <  0.001), fractional clearance index for urea (Kt/V) (r = - 0.404; P <  0.001) and urea reduction ratio (URR) (r = - 0.459; P <  0.001) were negatively correlated with HGS. According to our analysis, age (Odds ratio, OR = 1.11, 95% confidence interval, 95% CI = 1.05-1.17, P <  0.001), HD duration (OR = 1.01, 95% CI = 1.00-1.02, P = 0.010), diabetes (OR = 13.33, 95% CI = 3.45-51.53, P <  0.001), Kt/V (OR = 1.61, 95% CI = 1.06-2.46, P = 0.027), and SGA score (OR = 1.19, 95% CI = 1.03-1.38, P = 0.017) were regarded as independent predictors of low HGS. In contrast, ARB use (OR = 0.25, 95% CI = 0.07-0.93, P = 0.039) was independently associated with preserved HGS in chronic HD patients, after adjustment for multiple confounding factors.

CONCLUSIONS

Our study is the first report in chronic HD patients to indicate a potentially protective effect of ARB on muscle strength. However, further longitudinal follow-up and intervention studies are needed to confirm this finding.

Higher Intra-Dialysis Serum Phosphorus Reduction Ratio as a Predictor of Mortality in Patients on Long-Term Hemodialysis

Background

Rapid shifting between extracellular and intracellular phosphorus can occur during dialysis sessions, which can cause aberrant intracellular signaling in long-term hemodialysis (LTHD) patients. However, the effect of these intra-dialysis fluctuations of phosphorus on clinical outcomes has not been examined. Therefore, we investigated the relationship between intradialysis serum phosphorus reduction ratio (IDSPRR) and mortality in LTHD patients.

Material/Methods

This was a retrospective, observational cohort study to assess the predictive power of IDSPRR (>0.63 vs. ≤0.63) on mortality in a total of 805 LTHD patients. All these fatal events were analyzed using the Cox proportional hazards regression model.

Results

After multivariable analysis, baseline IDSPRR higher than 0.63 was significantly predictive of all-cause mortality (hazard ratio [HR]: 1.58; 95% confidence interval [CI]: 1.10–2.26), but not for cardiovascular (CV) mortality (HR: 1.41; 95% CI: 0.91–2.18). However, when time-varied IDSPRRs were applied, a value greater than 0.63 was not only significantly predictive of all-cause mortality (HR: 1.74, 95% CI: 1.16–2.63), but also CV mortality (HR: 2.04, 95% CI: 1.23–3.40).

Conclusions

High IDSPRR (>0.63) is independently associated with increased all-cause and CV mortality, which shows the negative effect of rapid intracellular phosphorus-shifting on LTHD patients.

Serum levels of sclerostin as a potential biomarker in central arterial stiffness among hypertensive patients

BACKGROUND

Sclerostin is known to be a canonical Wnt/β-catenin signaling pathway inhibitor, while the Wnt/β-catenin signaling pathway is proposed to be involved in the development of arterial stiffness. This study aims to investigate the relationship between serum sclerostin levels and carotid-femoral pulse wave velocity (cfPWV) among hypertensive patients.

METHODS

Fasting blood samples were obtained from 105 hypertensive patients. Patients with cfPWV values of > 10 m/s were classified in the high arterial stiffness group, whereas those with cfPWV values of ≤10 m/s were assigned to the low arterial stiffness group. Serum sclerostin and Dickkopf-1 (DKK1) levels were quantified using commercially available enzyme-linked immunosorbent assays.

RESULTS

Thirty-six hypertensive patients (34.3%) who belonged to the high arterial stiffness group were generally older (p < 0.001), presented with lower estimated glomerular filtration rates (eGFR, p = 0.014), higher incidence of diabetes mellitus (p = 0.030), average systolic blood pressures (SBP, p = 0.013), pulse pressure (p = 0.026), serum creatinine levels (p = 0.013), intact parathyroid hormone levels (iPTH, p = 0.003), and sclerostin levels (p < 0.001) than their counterparts in the low arterial stiffness group. A multivariable logistic regression analysis identified sclerostin as an independent predictor of arterial stiffness in hypertensive patients (odds ratio, 1.042; 95% confidence interval (CI), 1.017-1.068; p = 0.001). Multivariable forward stepwise linear regression analysis also showed that serum sclerostin level (β = 0.255, adjusted R2 change: 0.146, p = 0.003) was positively associated with cfPWV values in patients with hypertension.

CONCLUSIONS

In this study, serum sclerostin level, but not DKK1, is found to be positively correlated with cfPWV values and is identified as an independent predictor of arterial stiffness in hypertensive patients after adjusting for significant confounders.

Association of Serum Aluminum Levels with Mortality in Patients on Chronic Hemodialysis

Despite reported evidence on the relationship between higher serum aluminum levels and poor outcomes in patients on chronic hemodialysis (CHD), the acceptable cutoff value of serum aluminum for mortality remains unclear. A retrospective observational cohort study with 636 Taiwanese patients on CHD was conducted to investigate the impact of serum aluminum levels on mortality. The predictors were bivariate serum aluminum level (<6 and ≥6 ng/mL) and the Outcomes were all-cause and cardiovascular (CV) mortality. During the mean follow-up of 5.3 ± 2.9 years, 253 all-cause and 173 CV deaths occurred. Crude analysis showed that a serum aluminum level of ≥6 ng/mL was a significant predictor of all-cause [hazard ratio (HR), 1.80; 95% confidence interval (CI), 1.40–2.23] and CV (HR, 1.84; 95% CI, 1.36–2.50) mortality. After multivariable adjustment, the serum aluminum level of ≥6 ng/mL remained a significant predictor of all-cause mortality (HR, 1.37, 95% CI, 1.05–1.81) but became insignificant for CV mortality (HR, 1.29; 95% CI, 0.92–1.81). Therefore, our study revealed that a serum aluminum level of ≥6 ng/mL was independently associated with all-cause death in patients on CHD, suggesting that early intervention for aluminum level in patients on CHD might be beneficial even in the absence of overt aluminum toxicity.

A positive association between interleukin-1 receptor antagonist and insulin resistance in postmenopausal women

OBJECTIVE

The purpose of this study was to determine whether higher circulating interleukin-1 receptor antagonist (IL-1Ra), an anti-inflammatory cytokine, was associated with insulin resistance in postmenopausal women.

METHODS

We measured IL-1Ra concentrations in 160 naturally postmenopausal women without a history of diabetes mellitus. A Pearson coefficient was computed to assess the relationship between plasma IL-1Ra and homeostasis model assessment of insulin resistance (HOMA-IR). The association between HOMA-IR and IL-1Ra plasma level above the median was assessed by logistic regression. Linear regression was used to explore the determinants of IL-1Ra plasma levels.

RESULTS

A significant positive correlation existed between IL-1Ra and HOMA-IR (r = 0.42, p < .0001). The upper-tertile group of HOMA-IR was associated with approximately 4.5-fold increased risk of plasma IL-1Ra level above the median compared with the low-tertile group after adjustments. When multiple correlates were entered into the regression model simultaneously, only Log HOMA-IR remained significantly related to Log IL-1Ra (p = .007).

CONCLUSIONS

Our results demonstrated a positive association between plasma IL-1Ra and insulin resistance in postmenopausal women. This analysis suggested that insulin resistance was an important determinant of circulating IL-1Ra for these women.

Decreased serum fatty acid binding protein 4 concentrations are associated with sarcopenia in chronic hemodialysis patients

BACKGROUND

Fatty acid binding protein 4 (FABP4) is found to play a role in skeletal muscle homeostasis. Since the dysregulation of FABP4 and sarcopenia are both highly prevalent in patients on chronic hemodialysis (HD), the correlation between them remains unknown. We aimed to examine this relationship in a cross-sectional study.

METHODS

A total of 120 chronic HD patients were recruited, and whose skeletal muscle mass, handgrip strength, and gait speed were assessed and blood samples were obtained. We grouped these participants into sarcopenia (n = 20) and non-sarcopenia groups according to European Working Group on Sarcopenia in Older People criteria.

RESULTS

The sarcopenia group exhibited lower weight (P < 0.001), height (P = 0.019), waist circumference (P < 0.001), body mass index (P < 0.001), body fat mass (P = 0.004), and lower serum triglycerides (P = 0.009), creatinine (P < 0.001), phosphorus (P = 0.013), intact parathyroid hormone (P = 0.012), and FABP4 concentrations (P = 0.005), and higher malnutrition-inflammation scores (MIS) (P = 0.031), urea reduction rates (P < 0.001), and fractional clearance index for urea (Kt/V) values (P < 0.001). Serum FABP4 concentrations (odds ratio (OR): 0.98, 95% confidence interval (CI): 0.96-0.99, P = 0.043), body fat mass (OR: 0.86, 95% CI: 0.77-0.97, P = 0.013), MIS (OR: 6.90, 95% CI: 1.31-36.36, P = 0.023), and Kt/V (each increase of 0.1, OR: 2.15, 95% CI: 1.29-3.57, P = 0.003) were independent predictors of sarcopenia in chronic HD patients.

CONCLUSIONS

We delineated the association between serum FABP4 concentrations and sarcopenia in chronic HD patients.

Hyperleptinemia positively associated with central arterial stiffness in hemodialysis patients

Objective

Leptin plays a role in stimulating vascular inflammation, vascular smooth muscle hypertrophy, and augmenting blood pressure, which contributes to the pathogenesis of atherosclerosis and leads to arterial stiffness. This vascular damage, measured by carotid-femoral pulse wave velocity (cfPWV), is recognized as an independent predictor of cardiovascular mortality in hemodialysis (HD) patients. The aim of this study was to evaluate the relationship between serum leptin and arterial stiffness in HD patients.

Patients and methods

In 112 of the 126 HD patients were eligible and their biochemical data were collected for analysis. Serum leptin level was measured using a commercial enzyme-linked immunosorbent assay kit. Carotid-femoral pulse wave velocity was measured by a validated tonometry system (SphygmoCor). Those have cfPWV values above 10 m/s are defined as the high arterial stiffness group.

Results

Among the participants, thirty-eight of them who were in the high arterial stiffness group, had a higher prevalence of diabetes mellitus (p = 0.002), age (p = 0.029), body mass index (BMI, p = 0.018), body fat mass (p = 0.001), hemoglobin (p = 0.040), and serum leptin levels (P<0.001). Multivariable logistic regression analysis showed that leptin (odds ratio [OR] 1.09; 95% confidence interval [CI] 1.04–1.14; p <0.001), diabetes (OR 7.17; CI 1.39–37.00; p = 0.019), body fat mass (OR 1.16; CI 1.02–1.33; p = 0.027); and hemoglobin (OR 2.11; CI 1.15–3.87; p = 0.015) were independently associated with arterial stiffness in HD patients.

Conclusion

In our study, hyperleptinemia was positively correlated to the high cfPWV and thus was related to high arterial stiffness in HD patients.

A Practical Standardized Composite Nutrition Score Based on Lean Tissue Index: Application in Nutrition Screening and Prediction of Outcome in Hemodialysis Population

OBJECTIVE

Rapid screening and monitoring of nutritional status is mandatory in hemodialysis population because of the increasingly encountered nutritional problems. Considering the limitations of previous composite nutrition scores applied in this population, we tried to develop a standardized composite nutrition score (SCNS) using low lean tissue index as a marker of protein wasting to facilitate clinical screening and monitoring and to predict outcome.

DESIGN AND METHODS

This retrospective cohort used 2 databases of dialysis populations from Taiwan between 2011 and 2014. First database consisting of data from 629 maintenance hemodialysis patients was used to develop the SCNS and the second database containing data from 297 maintenance hemodialysis patients was used to validate this developed score.

RESULTS

SCNS containing albumin, creatinine, potassium, and body mass index was developed from the first database using low lean tissue index as a marker of protein wasting. When applying this score in the original database, significantly higher risk of developing protein wasting was found for patients with lower SCNS (odds ratio 1.38 [middle tertile vs highest tertile, P < .0001] and 2.40 [lowest tertile vs middle tertile, P < .0001]). The risk of death was also shown to be higher for patients with lower SCNS (hazard ratio 4.45 [below median level vs above median level, P < .0001]). These results were validated in the second database.

CONCLUSION

We developed an SCNS consisting of 4 easily available biochemical parameters. This kind of scoring system can be easily applied in different dialysis facilities for screening and monitoring of protein wasting. The wide application of body composition monitor in dialysis population will also facilitate the development of specific nutrition scoring model for individual facility.

Nationwide epidemiology and prognosis of dialysis-requiring acute kidney injury (NEP-AKI-D) study: Design and methods

AIM

Acute kidney injury (AKI) carries an increasing incidence rate worldwide and increases the risk of developing end-stage renal disease (ESRD) as well as the medical expenses during the post-AKI course. The Taiwan Consortium for Acute Kidney Injury and Renal Diseases (CAKs) has thus launched a nationwide epidemiology and prognosis of dialysis-requiring acute kidney injury (NEP-AKI-D) study, which prospectively enrols critically ill patients with AKI. Through thoroughly evaluating the risk and prognostic factors of AKI, we hope to lower the incidence of AKI and ESRD from the perspective of AKI-ESRD interaction.

METHODS

The CAKs includes 30 hospitals which distribute widely through the four geographical regions (north, middle, south, and east) of Taiwan, and have a 1:1 ratio of medical centres to regional hospitals in each region. The NEP-AKI-D study enrols intensive care unit-based AKI patients who receive dialysis in the four seasonal sampled months (October 2014, along with January, April, and July 2015) in the included hospitals. The collected data include demographic information, pertaining laboratory results, dialysis settings and patient outcomes. The data are uploaded in a centre website and will be audited by on-site principal investigators, computer logic gates, and the CAKs staffs. The outcomes of interest are in-hospital mortality, dialysis-dependency and readmission rate within 90 days after discharge.

CONCLUSION

The NEP-AKI-D study enrols a large number of representative AKI patients throughout Taiwan. The results of the current study are expected to provide more insight into the risk and prognostic factors of AKI and further attenuated further chronic kidney disease transition.

Hippocampal Atrophy Is Associated with Altered Hippocampus-Posterior Cingulate Cortex Connectivity in Mesial Temporal Lobe Epilepsy with Hippocampal Sclerosis

BACKGROUND AND PURPOSE

Unilateral mesial temporal lobe epilepsy and hippocampal sclerosis have structural and functional abnormalities in the mesial temporal regions. To gain insight into the pathophysiology of the epileptic network in mesial temporal lobe epilepsy with hippocampal sclerosis, we aimed to clarify the relationships between hippocampal atrophy and the altered connection between the hippocampus and the posterior cingulate cortex in patients with mesial temporal lobe epilepsy with hippocampal sclerosis.

MATERIALS AND METHODS

Fifteen patients with left mesial temporal lobe epilepsy with hippocampal sclerosis and 15 healthy controls were included in the study. Multicontrast MR imaging, including high-resolution T1WI, diffusion spectrum imaging, and resting-state fMRI, was performed to measure the hippocampal volume, structural connectivity of the inferior cingulum bundle, and intrinsic functional connectivity between the hippocampus and the posterior cingulate cortex, respectively.

RESULTS

Compared with controls, patients had decreased left hippocampal volume (volume ratio of the hippocampus and controls, 0.366% ± 0.029%; patients, 0.277% ± 0.063%, corrected P = .002), structural connectivity of the bilateral inferior cingulum bundle (generalized fractional anisotropy, left: controls, 0.234 ± 0.020; patients, 0.193 ± 0.022, corrected P = .0001, right: controls, 0.226 ± 0.022; patients, 0.208 ± 0.017, corrected P = .047), and intrinsic functional connectivity between the left hippocampus and the left posterior cingulate cortex (averaged z-value: controls, 0.314 ± 0.152; patients, 0.166 ± 0.062). The left hippocampal volume correlated with structural connectivity positively (standardized β = 0.864, P = .001), but it had little correlation with intrinsic functional connectivity (standardized β = -0.329, P = .113). On the contralesional side, the hippocampal volume did not show any significant correlation with structural connectivity or intrinsic functional connectivity (F_2,12 = 0.284, P = .757, R² = 0.045).

CONCLUSIONS

In left mesial temporal lobe epilepsy with hippocampal sclerosis, the left inferior cingulum bundle undergoes degeneration in tandem with the left hippocampal volume, whereas intrinsic functional connectivity seems to react by compensating the loss of connectivity. Such insight might be helpful in understanding the development of the epileptic network in left mesial temporal lobe epilepsy with hippocampal sclerosis.

Association between peripheral arterial occlusive disease and cardiothoracic ratio in patients on chronic hemodialysis

The cardiothoracic ratio (CTR) and peripheral arterial occlusive disease (PAOD) are related to mortality in hemodialysis patients. However, data on the association between PAOD and CTR are limited. In this study, we aim to elucidate this relationship in patients on chronic hemodialysis. Using a retrospective cross-sectional study of 622 Taiwanese patients, we investigated the association of PAOD and CTR. PAOD was significantly associated with CTR in the crude analysis. The odds ratio (OR) for CTR >0.5 was 1.77 [95% confidence interval (CI), 1.32-2.37], and the odds ratio for CTR >0.6 was 2.18 [95% CI, 1.44-3.30]. After adjusting for confounding variables, this difference continued to exhibit significant predictive power for CTR >0.6 (OR, 1.88; 95% CI, 1.14-3.11), but the predictive power for CTR >0.5 was attenuated (OR, 1.41; 95% CI, 0.98-2.03). In the subgroup analysis, PAOD was an independent factor for CTR >0.6, particularly in elderly and female patients or patients with hemoglobin >10 mg/dl and with no history of cardiovascular disease. In this research, we showed that the detection of PAOD was independently associated with CTR >0.6 in patients on chronic hemodialysis.

Triceps Skinfold Thickness Is Associated With Lumbar Bone Mineral Density in Peritoneal Dialysis Patients

Anthropometric measurements, including body mass index (BMI), body weight and total fat mass are associated with the bone mineral density (BMD) in the general population. Compared to that in the general population, BMD was lower in dialysis patients. However, the association between anthropometric measurements and BMD is not well-established among peritoneal dialysis (PD) patients. To study this, we conducted a cross-sectional study in 48 chronic PD patients. Anthropometric parameters, biochemical data, and BMD measured by dual energy X-ray absorptiometry in lumbar vertebrae (L2-L4) were collected. Among these PD patients, eight patients (16.7%) had osteoporosis and 22 patients (45.8%) osteopenia, while 18 patients were normal. Older age, decreased height, lower body weight, BMI, triceps skinfold thickness (TSF), mid-arm fat area (MAFA), and higher adiponectin levels were observed in our patients with lower lumbar T-scores. Height, body weight, waist circumference, BMI, body fat mass, TSF, mid-arm circumference, MAFA, and serum phosphorus levels were positively, while age, adiponectin levels were negatively correlated with lumbar BMD levels. According to our multivariate forward stepwise linear regression analysis, TSF (R² change = 0.080, P = 0.017) and body weight (R² change = 0.333, P = 0.002) were both correlated with low lumbar BMD. In conclusion, either TSF or body weight in our chronic PD patients was proved to be an independent predictor for osteolytic bone lesions.

Risk of Tuberculosis Among Patients on Dialysis: The Predictive Value of Serial Interferon-Gamma Release Assay

Patients on long-term dialysis are at high risk for tuberculosis (TB). Although latent tuberculosis infection (LTBI) is good target for TB eradication, interferon-gamma release assay-defined LTBI has a high proportion of negative conversion and lacks active TB correlation among patients on dialysis.Patients on long-term dialysis were screened in multiple centers in Taiwan. QuantiFERON-TB Gold In-tube (QFT-GIT) was used to define LTBI and was performed thrice at 6-month intervals. The primary outcome was active TB diagnosed after LTBI screening. The incidence and predictive value of QFT-GIT were analyzed.The 940 dialysis patients enrolled had an average age of 59.3 years. The initial QFT-GIT results were positive in 193, including 49.6% with persistent positive results on second check. In an average follow-up period of 3 years, 7 patients had TB. Three (319.1 per 100,000 person-yrs) and 4 (141.8 per 100,000 person-yrs) of them were prevalent and incident TB cases, respectively. Persistent positive QFT-GIT for 2 and 3 times correlated with increased hazard ratio for TB (14.44 and 20.29, respectively) compared with a single positive result (hazard ratio 10.38). Among those with 3 positive QFT-GIT results, TB development rate was 4.5% and incidence rate was 1352.3 per 100,000 person-years. In contrast, none of the incident TB occurred in those with initial positive and then negative conversion of QFT-GIT.In an area of intermediate TB incidence, dialysis patients have high TB risk. LTBI status is a good predictor of TB development, especially for those with more than 1 positive result. After excluding prevalent TB cases, serial follow-up of LTBI may narrow the target population to reduce treatment costs.

Serum Sclerostin as an Independent Marker of Peripheral Arterial Stiffness in Renal Transplantation Recipients: A Cross-Sectional Study

Wnt/β-catenin signaling pathway is thought to be implicated in the development of arterial stiffness and vascular calcification. As a Wnt signaling pathway inhibitor, it is interesting to investigate whether sclerostin or dickkopf-1 (DKK1) level is correlated with arterial stiffness in renal transplant (RT) recipients. Fasting blood samples were obtained for biochemical data, sclerostin, DKK1, and osteoprotegerin (OPG) determinations. In this study, we applied automatic pulse wave analyzer (VaSera VS-1000) to measure brachial-ankle pulse wave velocity and either sides of brachial-ankle pulse wave velocity value, which greater than 14.0 m/s was determined as high arterial stiffness. Among 68 RT recipients, 30 patients (44.1%) were in the high arterial stiffness group. Compared with patients in the low arterial stiffness group, patients in the high arterial stiffness group had higher prevalence of hypertension (P = 0.002), diabetes (P < 0.001), metabolic syndrome (P = 0.025), longer posttransplant duration (P = 0.005), higher systolic blood pressure (P < 0.001) and diastolic blood pressure (P = 0.018), and higher fasting glucose (P = 0.004), total cholesterol (P = 0.042), blood urea nitrogen (P = 0.020), phosphorus (P = 0.042), and sclerostin levels (P = 0.001). According to our multivariable forward stepwise linear regression analysis, age (β = 0.272, P = 0.014), phosphorus (β = 0.308, P = 0.007), and logarithmically-transformed OPG (log-OPG; β = 0.222, P = 0.046) were positively associated with sclerostin levels, and multivariate logistic regression analysis, sclerostin (odds ratio 1.052, 95% confidence interval 1.007-1.099, P = 0.024), and posttransplant duration (odds ratio 1.024, 95% confidence interval 1.004-1.045, P = 0.019) were the independent predictors of peripheral arterial stiffness in RT recipients. In this study, serum sclerostin level, but not DKK1, was proved to be involved in the pathogenetic process of peripheral arterial stiffness in RT recipients.

Factors associated with serum fetuin-A concentrations after long-term use of different phosphate binders in hemodialysis patients

Background

Fetuin-A is known as a circulating inhibitor of vascular calcification. Factors associated with serum fetuin-A concentrations after long-term use of different phosphate binders in hemodialysis patients is still uncertain.

Methods

In the post-hoc study, we analyzed serum fetuin-A and biochemical factors (Ca, P, i-PTH, hsCRP, TG, LDL-C) in 50 hemodialysis patients, who completed a 48-week, open-Label, controlled randomized parallel-group study. 23 patients received sevelamer and 27 patients received calcium carbonate.

Results

After the 48-week treatment, the sevelamer group had less serum calcium increment, less iPTH decrement, more ALK-P increment, more hsCRP decrement and more LDL-C decrement. There was no significant difference in the serum fetuin-A decrement between two groups. Decreased serum fetuin-A levels were found after 48-week treatment in both groups: from 210.61 (104.73) to 153.85 (38.64) ug/dl, P = 0.003 in sevelamer group, from 203.95 (107.87) to 170.90 (58.02) ug/mL, P =0.002 in calcium group. The decrement in serum fetuin-A (Δfetuin-A) levels was associated with ΔCa (ρ = - 0.230, P = 0.040), ΔiPTH (ρ = 0.306, P = 0.031) and Δalbumin (ρ = 0.408, P = 0.003), not associated with sevelamer use, ΔP and ΔhsCRP.

Conclusion

After long-term sevelamer or calcium carbonate treatment, both groups of maintenance HD patients had lower serum fetuin-A levels. Serum levels of increased calcium, decreased iPTH and decreased albumin were associated with the serum fetuin-A decrement.

High Fibroblast Growth Factor 23 Levels Associated With Low Hemoglobin Levels in Patients With Chronic Kidney Disease Stages 3 and 4

In chronic kidney disease (CKD), decreased erythropoietin production, low serum active vitamin D levels, and high renin-angiotensin-aldosterone activities had been regarded as major causes of renal anemia. At present, no clinical data are available to elucidate the association between renal anemia and fibroblast growth factor 23 (FGF23) levels in CKD. This study aimed to access whether FGF23 is involved in the pathogenesis of renal anemia. This cross-sectional observational study included 53 stable outpatients with CKD stages 3 and 4. Our primary predictor was serum FGF23 levels and outcome was hemoglobin levels. Measurements contained hemoglobin, FGF23, 25-hydroxyvitamin D, intact parathyroid hormone, plasma renin, serum aldosterone, HbA1C levels, lipid and iron profiles, and serum and urine electrolytes. Mean age of our patients was 66.4 ± 12.8 (SD) years, mean estimated glomerular filtration rate 33.5 ± 13.9 mL/min/1.73 m, median FGF23 level 200 (25th-75th percentile, 124-303) pg/mL, vitamin D level 19.5 (25th-75th percentile, 14.0-25.9) ng/mL, and hemoglobin level 12.7 (25th-75th percentile, 10.7-13.75) g/dL. Even after adjusting multiple variables, lower hemoglobin levels correlated significantly with FGF23 levels that were higher than the median value (>200 pg/mL). Moreover, after adjusting for aldosterone, but not 25-hydroxyvitamin D, it decreased the association with FGF23 that higher than median level and hemoglobin levels. We also observed a significant decrease of hemoglobin level in the higher FGF23 group who had a diabetes history. High FGF23 levels were observed to be associated with low hemoglobin levels, which may be partially mediated through the effects of serum aldosterone levels in our patients with CKD stages 3 and 4. Furthermore, we also presumed that diabetes itself may have an impact on the loop among FGF23, hemoglobin, and aldosterone levels in these CKD patients.

Trajectories of Serum Albumin Predict Survival of Peritoneal Dialysis Patients: A 15-year Follow-Up Study

Although initial serum albumin level is highly associated with overall and cardiovascular mortality in peritoneal dialysis (PD) patients, we consider that the dynamic change and trend of albumin after initiation of PD are also essential.We enrolled patients who received PD for more than 3 months from January 1999 to March 2014. We categorized these patients into 2 groups by the difference in serum albumin level (Δalbumin = difference between peak with initial albumin level = peak albumin level - initial albumin level) after PD. The patients with Δalbumin < 0.2 g/dL (median level) were considered as group A (n, number = 238) and those with Δalbumin ≥ 0.2 g/dL were considered as group B (n = 278). Further, we stratified these patients into quartiles: Q1 Δalbumin < -0.2 g/dL; Q2, -0.2 ≦∼ <0.2 g/dL; Q3, 0.2 ≦∼ <0.6 g/dL; and Q4, ≥0.6 g/dL. Regression analysis was performed to determine the correlation of initial albumin and Δalbumin.Group A patients presented with higher levels of serum albumin (3.71 ± 0.54 vs 3.04 ± 0.55 g/dL; P < 0.001) and hematocrit as well as better initial residual renal function. However, those in group A had lower serum albumin increment and downward-sloped trends after dialysis. In contrast, the albumin trend was upward sloped and the increment of albumin was remarkable in group B, despite the high prevalence of cardiovascular diseases and diabetes. Overtime, group A patients had poorer survival and experienced more frequent and longer hospitalizations. Group Q1 patients with least albumin increment had worst survival. Group Q4 patients with lowest initial albumin also had poor survival. Age, diabetes, cardiovascular diseases, BMI, initial albumin, and Δalbumin could affect patient outcomes independently. Regression analysis showed a better outcome can be obtained if the initial albumin level is at least above 3.15 g/dL. (Initial albumin level = -0.61 × Δalbumin + 3.50.)The increment and trend of albumin especially during early period of PD may be a more crucial determinant for survival.

Long-term sevelamer treatment lowers serum fibroblast growth factor 23 accompanied with increasing serum Klotho levels in chronic haemodialysis patients

AIMS

Fibroblast growth factor 23 (FGF23) and Klotho are associated with vascular calcification and cardiovascular disease in dialysis patients. Sevelamer has been shown to reduce progression of vascular calcification. This study aimed to determine the long-term effect of sevelamer treatment on serum FGF23 and Klotho levels in chronic haemodialysis (HD) patients.

METHODS

In the post-hoc analysis, we measured serum FGF23, Klotho and other biochemical factors (Ca, P, i-PTH, hsCRP, LDL-C) in 50 haemodialysis patients, who completed a 48-week, open-Label, controlled randomized parallel-group study. Twenty-three patients received sevelamer and 27 patients received calcium carbonate.

RESULTS

After 48-week sevelamer treatment, there were significant changes with lower LDL-C (from 2.82 ± 0.78 to 1.65 ± 0.53 mmol/L, P = 0.000), lower FGF23 (from 2465.97 (2568.88) to 795.61 (1098.39), P = 0.000) and higher s-Klotho levels (from 189.35 (161.88) to 252.94 (517.80) pg/mL, P = 0.000). In calcium carbonate group, there were no significant changes of LDL-C and FGF23, but with a borderline significant increase of s-Klotho level (from 142.34 (265.24) to 188.57 (252.38) pg/mL, P = 0.054). Multivariate analysis showed that FGF23 decrement was associated with sevelamer treatment (β = -0.277, P = 0.005), change of serum phosphate (β = 0.609, P = 0.000) and calcium levels (β = 0.635, P = 0.000). The increase of serum Klotho was associated with the decrease of serum phosphate (β = 0.490, P = 0.019).

CONCLUSION

Maintenance HD patients had lower serum FGF23 levels, accompanied with significantly increased serum Klotho levels, after 48-week sevelamer treatment. The FGF23 decrement was associated with sevelamer use, the change of serum phosphate and calcium levels. The serum Klotho increment was proportional to the phosphate-lowering power of the binders.

Relationship between Fibroblast Growth Factor 23 and Biochemical and Bone Histomorphometric Alterations in a Chronic Kidney Disease Rat Model Undergoing Parathyroidectomy

Background

Phosphate burden in chronic kidney disease (CKD) leads to elevated serum fibroblast factor-23 (FGF-23) levels, secondary hyperparathyroidism and chronic kidney disease-mineral bone disorder (CKD-MBD). However dissociated hyperphosphatemia and low serum FGF-23 concentrations have been observed in experimentally parathyoridectomized rats. The relationships between serum mineral, hormone, and bone metabolism may be altered in the presence of CKD. The aim of our study was to investigate whether a consistent relationship existed between serum FGF-23 levels, specific serum biochemical markers, and histomorphometric parameters of bone metabolism in a parathyroidectomized CKD animal model.

Results

Sprague Dawley rats were divided into 3 groups: parathyroidectomy (PTX) and CKD (PTX+CKD, 9 rats), CKD without PTX (CKD, 9 rats), and neither PTX nor CKD (sham-operated control, 8 rats); CKD was induced by partial nephrectomy. At 8 weeks after partial nephrectomy, serum biomarkers were measured. Bone histomorphometries of the distal femoral metaphyseal bone were analyzed. The mean serum FGF-23 levels and mean bone formation rate were the highest in the CKD group and the lowest in the PTX+CKD group. Bone volume parameters increased significantly in the PTX+CKD group. Pearson’s correlation revealed that serum FGF-23 levels associated with those of intact parathyroid hormone, phosphate, collagen type I C-telopeptide, and calcium. Univariate linear regression showed that serum FGF-23 values correlated with bone formation rate, bone volume, and osteoid parameters. Stepwise multivariate regression analysis revealed that circulating FGF-23 values were independently associated with bone volume and thickness (β = -0.737; p < 0.001 and β = -0.526; p = 0.006, respectively). Serum parathyroid hormone levels independently correlated with bone formation rate (β = 0.714; p < 0.001) while collagen type I C-telopeptide levels correlated with osteoid parameter.

Conclusion

Serum FGF-23 levels independently correlated with bone volume parameters in rats with experimentally induced CKD.

Sites of peripheral artery occlusive disease as a predictor for all-cause and cardiovascular mortality in chronic hemodialysis

Background

The ankle—brachial blood pressure (BP) index (ABI) not only indicates the presence of peripheral artery occlusive disease (PAOD) but predicts mortality in patients undergoing hemodialysis (HD). However, whether the site of PAOD can provide additional contribution to predicting mortality have not been investigated yet. Our primary objective was to determine the associations between the site of PAOD and all-cause and cardiovascular mortality in chronic HD (CHD) patients.

Methods

A retrospective cohort study was conducted to evaluate 444 Taiwanese CHD patients between December 2006 and June 2013. The site of PAOD together with other explanatory variables such as demographic data, body mass index, a history of cardiovascular diseases, HD vintage, biochemical data, and cardiothoracic ratio (CTR) were assessed by the Cox proportional hazards regression model.

Results

The frequency of PAOD was 14.6% in both legs, 4.9% in the right side only, and 5.1% in the left side only. During the study period, 127 all-cause and 93 cardiovascular deaths occurred. PAOD site was found to have significant predictive power for all-cause mortality with the order of 3.04 (95% CI: 1.56–5.90) hazard ratio on the right side, 2.48 (95% CI: 1.27–4.82) on the left side, and 4.11 (95% CI: 2.76–6.13) on both sides. The corresponding figures for cardiovascular mortality were 3.81 (95% CI: 1.87–7.76) on the right side, 2.76 (95% CI: 1.30–5.82) on the left side, and 3.95 (95% CI: 2.45–6.36) on both sides. After adjustment for other explanatory variables, only right-sided PAOD still remained to have significant predictive power for all-cause and cardiovascular mortality and bilateral PAOD kept the significant association with all-cause mortality.

Conclusions

The site of PAOD revealed various predictive powers for all-cause and cardiovascular mortality in CHD patients and only right-sided PAOD remained an independent predictor for both types of mortality making allowance for relevant confounding factors.

Sleep apnea and the risk of chronic kidney disease: a nationwide population-based cohort study

STUDY OBJECTIVES

Sleep apnea (SA) is characterized by apnea during sleep and is associated with cardiovascular diseases and an increase in all-cause mortality. Chronic kidney disease (CKD) is a global health problem that has placed a substantial burden on healthcare resources. However, the relationship between SA and the incidence of CKD is not clear. This study aimed to determine whether SA is an independent risk factor for the development of CKD.

DESIGN

Retrospective cohort study.

SETTING

National Health Insurance Research Database (NHIRD) of Taiwan.

PATIENTS OR PARTICIPANTS

A total of 4,674 adult patients (age ≥ 30 y) in whom SA was newly diagnosed from 2000 to 2010 were included, together with 23,370 non-SA patients as the comparison group. The two groups were frequency-matched for sex, age, and year of receiving medical service. Each individual was followed until 2011.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

These two groups were monitored and observed for the occurrence of CKD. Patients with SA experienced a 1.94-fold increase (95% confidence interval [CI], 1.52-2.46; P < 0.001) in the incidence of CKD, which was independent of sex, age, and comorbid medical conditions. Additionally, they showed a 2.2-fold increase (95% CI, 1.31-3.69; P < 0.01) in the incidence of end-stage renal disease (ESRD).

CONCLUSIONS

Patients with sleep apnea are at increased risk for chronic kidney disease and end-stage renal disease compared with the general population. As such, screening renal function and treatment of chronic kidney disease is an important issue in patients with sleep apnea.

Associations between the duration of dialysis, endotoxemia, monocyte chemoattractant protein-1, and the effects of a short-dwell exchange in patients requiring continuous ambulatory peritoneal dialysis

Background

Endotoxemia is exaggerated and contributes to systemic inflammation and atherosclerosis in patients requiring continuous ambulatory peritoneal dialysis (CAPD). The risk of mortality is substantially increased in patients requiring CAPD for >2 years. However, little is known about the effects of long-term CAPD on circulating endotoxin and cytokine levels. Therefore, the present study evaluated the associations between plasma endotoxin levels, cytokine levels, and clinical parameters with the effects of a short-dwell exchange on endotoxemia and cytokine levels in patients on long-term CAPD.

Methods

A total of 26 patients were enrolled and divided into two groups (short-term or long-term CAPD) according to the 2-year duration of CAPD. Plasma endotoxin and cytokine levels were measured before and after a short-dwell exchange (4-h dwell) during a peritoneal equilibration test (a standardized method to evaluate the solute transport function of peritoneal membrane). These data were analyzed to determine the relationship of circulating endotoxemia, cytokines and clinical characteristics between the two groups.

Results

Plasma endotoxin and monocyte chemotactic protein-1 (MCP-1) levels were significantly elevated in the long-term group. PD duration was significantly correlated with plasma endotoxin (r = 0.479, P = 0.016) and MCP-1 (r = 0.486, P = 0.012). PD duration was also independently associated with plasma MCP-1 levels in multivariate regression. Plasma MCP-1 levels tended to decrease (13.3% reduction, P = 0.077) though endotoxin levels did not decrease in the long-term PD group after the 4-h short-dwell exchange.

Conclusion

Long-term PD may result in exaggerated endotoxemia and elevated plasma MCP-1 levels. The duration of PD was significantly correlated with circulating endotoxin and MCP-1 levels, and was an independent predictor of plasma MCP-1 levels. Short-dwell exchange seemed to have favorable effects on circulating MCP-1 levels in patients on long-term PD.

Lower blood glucose and variability are associated with earlier recovery from renal injury caused by episodic urinary tract infection in advanced type 2 diabetic chronic kidney disease

PURPOSE

In our previous study, type 2 diabetic chronic kidney disease (CKD) patients with glomerular filtration rates of <30 mL/min upon hospitalization for urinary tract infection (UTI) were at a risk for acute kidney injury. This study aimed to clarify the effect of glucose and its variability on renal outcomes during admission for the treatment of UTI.

MATERIALS AND METHODS

Based on the date of renal recovery (RIFLE criteria: acute kidney injury occurred within 1-7 days and was sustained over 1 day), we divided these patients into early- (≤9 days, Group A) and late-recovery (>9 days, Group B) groups. The differences in the continuous and categorical variables of the two groups were assessed separately. The mean glucose levels and their variability (using the standard deviation and the coefficient of standard deviation) were compared at the fasting, midday pre-meal, evening pre-meal, and evening post-meal time points during hospitalization. We have organized the manuscript in a manner compliant with the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) statement.

RESULTS

Acute kidney injury occurred within the two groups (p = 0.007 and p = 0.001, respectively). The early-morning blood glucose levels (149.7±44.0 mg/dL) and average blood glucose levels (185.6±52.0 mg/dL) were better in Group A (p = 0.01, p = 0.02). Group A patients also had lower glucose variability than Group B at the different time points (p<0.05). Group A also had earlier renal recovery. More relevant pathogens were identified from blood in Group B (p = 0.038).

CONCLUSIONS

Early-morning fasting and mean blood glucose levels and their variability can be good indicators of severe infection and predictors of renal outcome in type 2 diabetic patients with CKD and UTI.

Survival and other clinical outcomes of maintenance hemodialysis patients in Taiwan: a 5-year multicenter follow-up study

The increasing aging and diabetes mellitus (DM) patients in dialysis population make the quality maintenance of dialysis an imperative issue. Recently, an increasing number of dialysis centers were run by private dialysis providers, many of which apply quality assurance programs and performance management systems to dialysis care. We studied patients in dialysis facilities in Taiwan run by a private chain to see clinical outcomes of centers operating under these systemic strategies. Hemodialysis patients from January 1, 2008 to December 31, 2012 in 25 dialysis facilities in Taiwan, which received the management and consultation from a dialysis service provider, NephroCare (NC), were included. Data pivotal to quality of dialysis were analyzed. During a 5-year interval, 5161 hemodialysis patients were included. For volume control, the proportion of patients with weight gain ≥4.5% decreases from 41.7% to 30.2%. Mean Kt/V is 1.74 ± 0.28. Mean albumin level is 3.92 ± 0.38 g/dL. Patients with phosphate <5.5 mg/dL is up to 71.8%. The mean hemoglobin level is 10.70 ± 1.40 g/dL. More than 80% of patients have adequate iron status. Further, 73% of patients use native arteriovenous fistula. Hospitalization-free survival rate was 56% at the fifth year. Patient survival rate at the fifth year was 66.4%. Overall clinical performances were maintained very stable in NC facilities from this temporal data analysis. The hospitalization and survival rate also compare favorably with those reported internationally. These results warrant further studies to justify the application of this kind of quality assurance programs and performance management systems in dialysis care.

Shorter daily dwelling time in peritoneal dialysis attenuates the epithelial-to-mesenchymal transition of mesothelial cells

Background

Peritoneal dialysis (PD) therapy is known to induce morphological and functional changes in the peritoneal membrane. Long-term exposure to conventional bio-incompatible dialysate and peritonitis is the main etiology of inflammation. Consequently, the peritoneal membrane undergoes structural changes, including angiogenesis, fibrosis, and hyalinizing vasculopathy, which ultimately results in technique failure. The epithelial-to-mesenchymal transition (EMT) of mesothelial cells (MCs) plays an important role during the above process; however, the clinical parameters associated with the EMT process of MCs remain to be explored.

Methods

To investigate the parameters impacting EMT during PD therapy, 53 clinical stable PD patients were enrolled. EMT assessments were conducted through human peritoneal MCs cultured from dialysate effluent with one consistent standard criterion (MC morphology and the expression of an epithelial marker, cytokeratin 18). The factors potentially associated with EMT were analyzed using logistic regression analysis. Primary MCs derived from the omentum were isolated for the in vitro study.

Results

Forty-seven percent of the patients presented with EMT, 28% with non-EMT, and 15% with a mixed presentation. Logistic regression analysis showed that patients who received persistent PD therapy (dwelling time of 24 h/day) had significantly higher EMT tendency. These results were consistent in vitro.

Conclusions

Dwelling time had a significant effect on the occurrence of EMT on MCs.