Utility of remote monitoring in patients on automated peritoneal dialysis.

Home hemodialysis (HD) and automated peritoneal dialysis (APD) have advantages over HD in hospitals or HD centers. Home therapies are generally less expensive and give patients greater mobility and freedom for work, school, family, and recreational activities. Technological advances have made it possible to complement APD with devices for remote monitoring (RM) of the patient. With them, objective information generated in the APD device is collected and sent to repositories "in the cloud" for analysis or at the time decided by the health team. With APD+RM, it is possible to monitor therapeutic compliance, effective dialysis time, ultrafiltration volumes, inflow and outflow patterns of dialysis fluid, and patient actions to respond to alarms that indicate deviations from the parameters set by the nephrologist. The results of APD+RM show good acceptance by the patient, nephrologists, and nurses, treatment adherence has improved, hospitalizations and technique failure have decreased, and some aspects of quality of life have improved. However, there is a lack of controlled clinical trials that reliably demonstrate lower mortality and comorbidity due to specific causes.

Remote monitoring as a surveillance method in patients on automated peritoneal dialysis for preventing complications and COVID-19 contagion.

BACKGROUND: Due to the health emergency of COVID-19, telemedicine has become more relevant. Remote monitoring conspicuous as a valuable tool for the clinical follow-up of kidney patients, in this case, who are treated with automated peritoneal dialysis. This study aims to describe the use of remote monitoring as a surveillance method in a cohort of patients on automated peritoneal dialysis prevent complications and COVID-19 contagion. METHODS: Study of a cohort of patients who initially participated in a randomized block clinical trial in which the use of Automated Peritoneal Dialysis with Remote Monitoring (APD-RM) was compared with conventional treatment. A descriptive analysis was performed of the rates of infection by COVID-19, the time of incidence until this, mortality, and rates of transfer to hemodialysis. In addition, survival was measured by survival curves. RESULTS: Of the 509 patients, 19 were positive for COVID-19 (incidence rate of 7.0 episodes/100 patient-year), and only six patients recovered from the infection; the death rate was 2.6 % compared to all-cause death of 9.8 %. The most affected group of patients were those over 50 years old, with 71.4 % mortality, in contrast to younger patients infected, with a mortality of 60 %. During the follow-up period, 21 patients were transferred to HD: six due to peritonitis, five due to UF failure, seven due to catheter dysfunction, one due to uremic syndrome, one due to COVID-19, and one by surgical intervention. CONCLUSION: APD-RM patients have a significant advantage over other dialysis therapies because the use of telemedicine not only provides continuity in the patient's clinical treatment but also favors the prevention of COVID-19 infection, the management and prevention of complications inherent to therapy and the preservation of the life of Peritoneal Dialysis patients.

Sex Modulates Cardiovascular Effects of Icodextrin-Based Peritoneal Dialysis Solutions.

Background/Aims: Some previous observations have noted that after six months of peritoneal dialysis (PD) treatment with icodextrin solutions, blood pressure (BP) and NT-proBNP tend to return to baseline values. This may be due to accumulation of icodextrin products that exert a colloid osmotic effect, which drives water into the bloodstream, causing the rise in blood pressure. Since icodextrin is metabolized by α-Amylase and its gene copies are lower in females than in males, we hypothesized icodextrin metabolites reach higher concentrations in females and that cardiovascular effects of icodextrin are influenced by sex. Methods: Secondary analysis of a RCT comparing factors influencing fluid balance control in diabetic PD patients with high or high average peritoneal transport receiving icodextrin (n = 30) or glucose (n = 29) PD solutions. Serum icodextrin metabolites, osmolality, body composition and Inferior Vena Cava (IVC) diameter were measured at baseline, and at 6 and 12 months of follow-up. Results: After six months of treatment, icodextrin metabolites showed higher levels in females than in males, particularly G5-7 and >G7, serum osmolality was lower in females. In spite of reduction in total and extracellular body water, ultrafiltration (UF) was lower and IVC diameter and BP increased in females, suggesting increment of blood volume. Conclusion: Females undergoing PD present with higher levels of icodextrin metabolites in serum that may exert an increased colloid-osmotic pressure followed by less UF volumes and increment in blood volume and blood pressure. Whether this could be due to the lesser number of α-Amylase gene copies described in diabetic females deserves further investigation.

La disminución de triyodotironina se asocia con la elevación del péptido natriurético cerebral N-terminal y con la mortalidad en pacientes en diálisis / Low triiodothyronine is associated with elevation of N-terminal pro-brain natriuretic peptide (NT-proBNP) and mortality in dialysis patients

Antecedentes: La disminución de hormonas tiroideas (HT) y el daño miocárdico son frecuentes en pacientes en diálisis y están asociados con la mortalidad. Sin embargo, poco se conoce de la importancia de las HT como factor de daño miocárdico, como se ha descrito en las enfermedades tiroideas primarias. El objetivo de este estudio fue explorar si existe interacción entre la disminución de triyodotironina total (tT3) y los marcadores de daño miocárdico y la relación de esta interacción entre ambos con la mortalidad, para establecer si el daño cardiovascular es el vínculo entre la disminución de HT y el riesgo de muerte en pacientes con ERC en diálisis. Material y métodos: Se estudiaron los niveles plasmáticos de HT, de marcadores de nutrición, inflamación y de daño al miocardio en 296 pacientes en diálisis peritoneal o en hemodiálisis, a los que se vigiló por 16 meses para conocer la asociación de las variables bioquímicas con la mortalidad. Resultados: En el 45% de los pacientes se encontró tT3 disminuida, lo cual tuvo correlación inversa con la proteína C reactiva (PCR) y con el NT-proBNP y directa con la albúmina y la transferrina. La diabetes, la PCR y la tT3 fueron factores de riesgo para la mortalidad por cualquier causa y la PCR, el NT-proBNP y la tT3 para mortalidad cardiovascular. Conclusiones: Los niveles bajos de tT3 son frecuentes en pacientes en diálisis, se asocian con inflamación, desnutrición y daño miocárdico: este último puede ser el vínculo entre la disminución de HT y la mortalidad por cualquier causa y la mortalidad cardiovascular (AU)

Background: Low thyroid hormone (TH) levels and myocardial damage are common in dialysis patients and are associated with mortality. However, little is known about the role of THs on myocardial damage as has been described in primary thyroid diseases. The aim of this study was to explore the potential relationship between low total triiodothyronine (total T3) and biomarkers of myocardial damage and the effect of their interaction on mortality, to ascertain if cardiovascular damage is the link between low THs and the risk of death in dialysis patients with CKD. Material and methods: TH plasma levels, nutritional markers, inflammation and myocardial damage were studied in 296 patients undergoing peritoneal dialysis or haemodialysis, who were followed up for 16 months to ascertain the association between biochemical variables and mortality. Results: Low total T3 levels were found in 45% of patients, which was inversely correlated with C-reactive protein (CRP) and NT-proBNP, and directly correlated with albumin and transferrin. Diabetes, CRP and total T3 were risk factors for all-cause mortality, and CRP, NT-proBNP and total T3 for cardiovascular mortality. Conclusions: Low total T3 levels are common in dialysis patients and are associated with inflammation, malnutrition and myocardial damage. The latter may be the link between low THs and all-cause and cardiovascular mortality (AU)

Low triiodothyronine is associated with elevation of N-terminal pro-brain natriuretic peptide (NT-proBNP) and mortality in dialysis patients. / La disminución de triyodotironina se asocia con la elevación del péptido natriurético cerebral N-terminal y con la mortalidad en pacientes en diálisis.

BACKGROUND: Low thyroid hormone (TH) levels and myocardial damage are common in dialysis patients and are associated with mortality. However, little is known about the role of THs on myocardial damage as has been described in primary thyroid diseases. The aim of this study was to explore the potential relationship between low total triiodothyronine (total T3) and biomarkers of myocardial damage and the effect of their interaction on mortality, to ascertain if cardiovascular damage is the link between low THs and the risk of death in dialysis patients with CKD. MATERIAL AND METHODS: TH plasma levels, nutritional markers, inflammation and myocardial damage were studied in 296 patients undergoing peritoneal dialysis or haemodialysis, who were followed up for 16 months to ascertain the association between biochemical variables and mortality. RESULTS: Low total T3 levels were found in 45% of patients, which was inversely correlated with C-reactive protein (CRP) and NT-proBNP, and directly correlated with albumin and transferrin. Diabetes, CRP and total T3 were risk factors for all-cause mortality, and CRP, NT-proBNP and total T3 for cardiovascular mortality. CONCLUSIONS: Low total T3 levels are common in dialysis patients and are associated with inflammation, malnutrition and myocardial damage. The latter may be the link between low THs and all-cause and cardiovascular mortality.

Blood pressure rhythmicity in patients with end stage chronic kidney disease: bromocriptine effect / Ritmicidad de la presión arterial en pacientes con enfermedad renal crónica terminal: efecto de bromocriptina

BACKGROUND: The aim of this paper was to characterize the blood pressure CR in patients with end stage chronic kidney disease (ESCKD) before and after treatment with bromocriptine compared to healthy volunteers. METHODS: Fifteen patients and nine healthy volunteers were included. Both groups underwent ambulatory 24 hours blood pressure (24 h ABPM). Patients received 2.5 mg every 8 hours of bromocriptine for eight weeks, at the end of the treatment 24 h ABPM was repeated; blood pressure CR was compared before and after treatment and with healthy volunteers. The CR was identified by the method of Cosinor. RESULTS: 64% of volunteers showed a 24 h CR, against 27% of patients (p < 0.05). After the treatment with bromocriptine 40% of patients showed RC 24 h. The mean arterial pressure decreased from 129 ± 1 mmHg to 106 ± 1 mmHg. A 12 h rhythm was identified in 45% of volunteers and 73% of patients before treatment (p < 0.05) against 60% at the end (p < 0.001), with no statistical difference with volunteers. CONCLUSIONS: The CR in blood pressure is altered in ESCKD and could be restored with bromocriptine. 12 hours rhythmicity was identified predominantly in patients with ESCKD; this rhythm was also present in the healthy volunteers.

INTRODUCCIÓN: el propósito de este estudio es caracterizar el ritmo circadiano (RC) de la presión arterial en pacientes con enfermedad renal crónica terminal (ERCT) en tratamiento con diálisis peritoneal continua ambulatoria (DPCA) antes y después del tratamiento con bromocriptina (BEC) comparándolos con voluntarios sanos. MÉTODOS: se incluyeron 15 pacientes del servicio de Nefrología y 9 voluntarios sanos. Se les realizó monitoreo ambulatorio de presión arterial de 24 horas (MAPA). Los pacientes recibieron 2.5 mg de BEC cada 8 hora durante ocho semanas, al final del tratamiento se repitió el MAPA; el RC de la presión arterial se comparó antes y después del tratamiento y con los voluntarios. Resultados: el 64% de los voluntarios exhibieron RC de 24 horas, frente al 27% de los pacientes (p < 0.05). Después del tratamiento con BEC, el 40% de pacientes mostraron RC de 24 h. El mesor de la presión arterial media disminuyó de 129 ± 1 mmHg a 106 ± 1 mmHg (p < 0.05). Se identificó un ritmo de 12 h en 45% de los voluntarios y en el 73% de los pacientes antes del tratamiento (p < 0.05) frente a 60% al final (p < 0.001), sin diferencia estadística con los voluntarios. CONCLUSIONES: el RC de la presión arterial esta alterado en la IRCT y se restableció con BEC. La ritmicidad de 12 h predominó en los pacientes con ERCT, también presente en los voluntarios sanos.

[Factors related to residual renal function loss in patients in peritoneal dialysis]. / Factores relacionados con pérdida de la función renal residual en pacientes en diálisis peritoneal.

BACKGROUND: Residual renal function (RRF) contributes to the quality of life of patients on dialysis. The preservation of RRF is associated with higher patient survival in peritoneal dialysis (PD), and is now accepted that RRF and peritoneal clearance are not of equal value in patient survival. The aim of this study is to know the factors related to RRF loss in prevalent patients in continuous ambulatory peritoneal dialysis (CAPD). METHODS: This is an analysis of secondary outcomes. Forty-three adult patients with type 2 diabetes were included. They had RRF preserved. Clinical and laboratory assessments were done in each visit during a year. RESULTS: The male gender (p = 0.042), systolic (p = 0.009) and diastolic (p = 0.006) blood pressure (BP), hemoglobin (p = 0.008), peritoneal creatinine clearance (p = 0.014), peritoneal ultrafiltration (p = 0.017) and levels of tumor necrosis factor-alpha (TNF-alpha) in plasma (p = 0.022) and dialysate (p = 0.008) were related with RRF loss. CONCLUSIONS: It is important to understand the factors associated with RRF loss in our patients to prevent the gradual loss and its implications on the mortality and quality of life.

Introducción: la conservación de la función renal residual (FRR) en los pacientes en diálisis peritoneal (DP) tiene una clara influencia sobre la calidad de vida, independientemente de que su preservación ha demostrado influir en la mayor supervivencia de los pacientes. El objetivo del presente estudio fue conocer los factores relacionados con pérdida de la FRR en un grupo de pacientes prevalentes en diálisis peritoneal continua ambulatoria (DPCA). Métodos: se trata de un estudio de análisis de resultados secundarios. Se incluyeron 43 adultos con diabetes tipo 2 (DT2), con FRR conservada, a quienes se les dio seguimiento durante un año. Resultados: los factores relacionados con la pérdida de la FRR fueron: género masculino (p = 0.042), presión arterial sistólica (p = 0.009) y diastólica (p = 0.006), hemoglobina (p = 0.008), aclaramiento peritoneal de creatinina (p = 0.014), ultrafiltración (p = 0.017), niveles de factor de necrosis tumoral alfa (FNT­alfa) en plasma (p = 0.022) y dializado (p = 0.008). Conclusiones: es importante conocer los factores relacionados con pérdida de la FRR en nuestros pacientes para evitar la pérdida gradual de la misma y sus implicaciones sobre la mortalidad y calidad de vida.

Inflammation and myocardial damage markers influence loss of residual renal function in peritoneal dialysis patients.

BACKGROUND: Residual renal function (RRF) has been identified as the most important component in dialysis adequacy and has a strong effect on clinical outcomes. This justifies any effort in understanding the mechanism behind the preservation or decline in RRF. The aim of this study was to analyze the possible association of components of cardio-renal syndrome with the rate of decline in RRF. METHODS: A retrospective cohort study was performed in a group of prevalent adult patients on continuous ambulatory peritoneal dialysis (CAPD). Patients were analyzed at baseline and after a 30-month follow-up. Evaluations included measurements of residual renal function, dialysis adequacy parameters, cardiovascular comorbidity, and measurements of biochemical markers of cardiovascular disease (CVD) and inflammation, as well as resting electrocardiography. RESULTS: We included 129 patients in the study who were divided into groups according to loss of RRF, considering the cut-off point as 100 mL/day of 24 h urine volume. At baseline, there were no differences between groups: patients who lost RRF showed low values of 24 h urine volume, higher levels of systolic blood pressure, N-terminal pro-brain natriuretic peptide (NT-proBNP), C-reactive protein (CRP), IL-6, and low values of serum albumin. In the multivariate analysis, age, albumin, CRP, and NT-proBNP were significant risk factors for the loss of RRF. CONCLUSIONS: Data indicate a close relationship between heart and kidney function where chronic kidney disease (CKD) affects and is an effect of, heart function, indicative of a bi-directional influence that leads to a vicious cycle, promoting deleterious effects on both systems.

Effect of icodextrin on heart rate variability in diabetic patients on peritoneal dialysis.

INTRODUCTION: Spectral analysis of heart rate variability is a noninvasive method for evaluating autonomic cardiovascular dysfunction under various clinical conditions, such as in dialysis patients, in whom an imbalance between the sympathetic and parasympathetic nervous system appears to be an important risk factor for sudden cardiovascular death and arrhythmia. ♢ OBJECTIVE: We compared the effect of icodextrin-based dialysis solution, an option that allows for better metabolic and fluid overload control, with that of glucose-based dialysis fluid on sympathetic and parasympathetic activity in the heart, as assessed by heart rate variability, in diabetic patients on peritoneal dialysis (PD). ♢ METHODS: This secondary analysis uses data from a randomized controlled trial in diabetic PD patients with high or high-average peritoneal transport using icodextrin-based (ICO group, n = 30) or glucose-based (GLU group, n = 29) solutions for the long dwell. All patients underwent 24-hour electrocardiographic Holter monitoring at baseline, and at 6 and 12 months of follow-up. ♢ RESULTS: We observed no significant differences between the groups in most of the variables analyzed, although values were, in general, below reference values. In the ICO group, total power and both low- and high-frequency power in normalized units increased, but the percentage of RR intervals with variation of more than 50 ms declined over time; in the GLU group, all those values declined. Plasma catecholamine levels were higher at baseline and declined over time. ♢ CONCLUSIONS: These results indicate a partial recovery of sympathetic activity in the ICO group, probably because of better extracellular fluid control and lower exposure to glucose with the use of icodextrin-based dialysis solutions.

Dialysis adequacy indices and body composition in male and female patients on peritoneal dialysis.

OBJECTIVES: Creatinine clearance scaled to body surface area (BSA) and urea KT/V normalized to total body water (TBW) are used as indices for peritoneal dialysis (PD) adequacy. We investigated relationships of indices of dialysis adequacy (including KT/V, KT, clearance, dialysate over plasma concentration ratio) and anthropometric and body composition parameters (BSA, TBW, body mass index (BMI), weight, height, fat mass (FM), and fat-free mass (FFM)) in male and female patients on continuous ambulatory peritoneal dialysis. METHODS: Ninety-nine stable patients (56 males) performed four 24-hr collections of drained dialysate for four dialysis schedules with three daily exchanges of glucose 1.36% and one night exchange of either: 1) glucose 1.36%, 2) glucose 2.27%, 3) glucose 3.86% or 4) icodextrin 7.5%. RESULTS: KT and dialysate over plasma concentration ratio, CD/CP, for urea and creatinine were similar for males and females and, in general, did not depend on body-size parameters including V (= TBW), which means that the overall capacity of the transport system in females and males is similar. However, after normalization of KT to V or 1.73/BSA yielding KT/V and creatinine clearance, Cl(1.73/BSA), respectively, the normalized indices were substantially higher in females than in males and correlated inversely with body-size parameters, especially in males. CONCLUSIONS: As KT/V depends strongly on body size, treatment target values for KT/V should take body size and therefore also gender into account. As KT is less influenced by body size, body composition and gender, KT should be considered as a potential auxiliary index in PD.

De novo development of heart valve calcification in incident peritoneal dialysis patients.

BACKGROUND AND AIMS: Cardiac valve calcification (VC) is a frequent complication in chronic kidney disease and is considered a risk factor for all-cause and cardiovascular mortality. However, little is known about the pathophysiology mechanisms that originate it and the factors associated with its development. We undertook this study to analyze the frequency and factors related to de novo development of mitral valve calcification (MVC) and aortic valve calcifications (AVC) in incident peritoneal dialysis (PD) patients. METHODS: A prospective cohort of 124 incident PD patients was studied. Demographic and clinical data were recorded and blood assayed at baseline and after 1 year of follow-up for calcium, phosphorus, glucose, urea, creatinine, cholesterol, triglycerides by spectrophotometry assay; high-sensitivity C-reactive protein (CRP) by immunoturbidimetric ultrasensitive assay, intact parathormone (iPTH) and osteocalcin by electrochemiluminescence, fetuin-A and osteoprotegerin by EDI-ELISA. Valve calcification was evaluated by M-mode bidimensional echocardiogram. RESULTS: Sixty eight percent of patients were male, ages 43 ± 13 years; 51% were diabetic with 1.4 ± 1 months on PD. After 12.3 ± 1 months, 57 patients (46%) developed VC: AVC in 33 (57.8%), MVC in 15 (26.3%) and 9 (15.8%) patients in both valves. There was no correlation between AVC and MCV. In univariate logistic regression analysis, age, diabetes and elevated concentrations of OPG, iPTH and CRP were risk factors for development MVC. In multivariate analysis, only iPTH remained an independent risk factor as was also the case in AVC. CONCLUSIONS: Age, diabetes, osteoprotegerin, parathormone and C-reactive protein are risk factors related to de novo development of MVC and iPTH for AVC in incident dialysis patients.

Cardiovascular and renal effects of bromocriptine in diabetic patients with stage 4 chronic kidney disease.

OBJECTIVE: The objective of this study was to investigate the effect of bromocriptine (BEC) on left ventricular mass index (LVMI) and residual renal function (RRF) in chronic kidney disease (CKD) patients with type 2 diabetes (T2D). RESEARCH DESIGN AND METHODS: A 6-month double-blind randomized controlled trial was conducted in 28 patients with T2D and stage 4 CKD with increased LVMI. Fourteen patients received BEC (2.5 mg, initially 1 tablet with subsequent increase to three times a day) and 14 received a placebo (PBO; initially 1 tablet with subsequent increase to three times a day). Cardiovascular changes were assessed by monitoring 24 h ambulatory blood pressure, two-dimensional-guided M-mode echocardiography, and N-terminal brain natriuretic peptide (NT-proBNP) plasma levels. RRF was evaluated by creatinine clearance and cystatin-C plasma levels. RESULTS: Both BEC and PBO groups decreased blood pressure-but the effect was more pronounced in the BEC group. Average 24 h, diurnal and nocturnal blood pressures, and circadian profile showed improved values compared to the PBO group; LVMI decreased by 14% in BEC and increased by 8% in PBO group. NT-proBNP decreased in BEC (0.54 ± 0.15 to 0.32 ± 0.17 pg/mL) and increased in PBO (0.37 ± 0.15 to 0.64 ± 0.17 pg/mL). Creatinine clearance did not change in the BEC group and decreased in the PBO group. CONCLUSIONS: BEC resulted in a decrease on blood pressure and LVMI. BEC also prevented the progression of CKD while maintaining the creatinine clearance unchanged.

Reaching targets for mineral metabolism clinical practice guidelines and its impact on outcomes among Mexican chronic dialysis patients.

BACKGROUND AND AIMS: An increasing number of studies have been published concerning meeting targets of clinical guidelines for different aspects of the diagnosis and treatment of patients with end-stage renal disease. Most of these studies have shown that guideline recommendations are not always satisfied, and results outside target limits have been associated with high rates of mortality and morbidity. The objective of this study was to analyze the frequency of reaching mineral and bone metabolism-related guideline targets and its impact on clinical outcomes in Mexican chronic dialysis patients. METHODS: A cohort of prevalent peritoneal dialysis (PD) and hemodialysis (HD) patients were analyzed at baseline and followed for at least 16 months. Patients were on continuous ambulatory peritoneal dialysis (CAPD), automated peritoneal dialysis (APD), and HD and contracted HD modalities where patients received HD sessions outside institution facilities. RESULTS: We studied 753 patients. The percentage of patients within target limits for phosphorus was 35%, for calcium 32%, and for PTH 12%. The most frequent pattern was hyperphosphatamia, hypercalcemia, and low PTH. This was even more frequent in CAPD patients, probably due to the high percentage of diabetic patients. Hypercalcemia was found as an independent risk factor for mortality. CONCLUSIONS: The most important results suggest that guideline recommendations are not usually satisfied and that hypercalcemia, in addition to other traditional risk factors, is associated with high mortality rates. The study also detected some opportunities to improve the quality of treatment by reducing the calcium content of dialysis solutions and reducing the use of calcium carbonate as a phosphate binder.

Threefold peritoneal test of osmotic conductance, ultrafiltration efficiency, and fluid absorption.

BACKGROUND: Fluid removal during peritoneal dialysis depends on modifiable factors such as tonicity of dialysis fluids and intrinsic characteristics of the peritoneal transport barrier and the osmotic agent-for example, osmotic conductance, ultrafiltration efficiency, and peritoneal fluid absorption. The latter parameters cannot be derived from tests of the small-solute transport rate. We here propose a simple test that may provide information about those parameters. METHODS: Volumes and glucose concentrations of drained dialysate obtained with 3 different combinations of glucose-based dialysis fluid (3 exchanges of 1.36% glucose during the day and 1 overnight exchange of either 1.36%, 2.27%, or 3.86% glucose) were measured in 83 continuous ambulatory peritoneal dialysis (CAPD) patients. Linear regression analyses of daily net ultrafiltration in relation to the average dialysate-to-plasma concentration gradient of glucose allowed for an estimation of the osmotic conductance of glucose and the peritoneal fluid absorption rate, and net ultrafiltration in relation to glucose absorption allowed for an estimation of the ultrafiltration effectiveness of glucose. RESULTS: The osmotic conductance of glucose was 0.067 ± 0.042 (milliliters per minute divided by millimoles per milliliter), the ultrafiltration effectiveness of glucose was 16.77 ± 7.97 mL/g of absorbed glucose, and the peritoneal fluid absorption rate was 0.94 ± 0.97 mL/min (if estimated concomitantly with osmotic conductance) or 0.93 ± 0.75 mL/min (if estimated concomitantly with ultrafiltration effectiveness). These fluid transport parameters were independent of small-solute transport characteristics, but proportional to total body water estimated by bioimpedance. CONCLUSIONS: By varying the glucose concentration in 1 of 4 daily exchanges, osmotic conductance, ultrafiltration efficiency, and peritoneal fluid absorption could be estimated in CAPD patients, yielding transport parameter values that were similar to those obtained by other, more sophisticated, methods.

Ultrafiltration and dialysis adequacy with various daily schedules of dialysis fluids.

Dialysis regimens for continuous ambulatory peritoneal dialysis (CAPD) patients vary with the need for fluid removal, but also because of concerns about the local and systemic consequences of high glucose exposure. The implications of various regimens for dialysis adequacy--that is, fluid and small-solute removal--are not always clear. We therefore analyzed ultrafiltration (UF) and adequacy indices for 4 different combinations of dialysis fluid. Collections of 24-hour dialysate and urine were carried out in 99 patients on CAPD. On 4 separate occasions, each patient performed 4 exchanges in 24 hours, including 3 daily exchanges with 1.36% glucose and 1 night exchange with either 1.36% glucose (G1 schedule), 2.27% glucose (G2 schedule), 3.86% glucose (G3 schedule), or icodextrin (Ico schedule). Weekly, total, and dialysis Kt/V and KT were calculated for both urea and creatinine. The mean values of urea Kt/V and KT were significantly lower for the G1 schedule than for the G3 and Ico schedules. The adequacy indices for overnight application of 3.86% glucose and icodextrin were similar. Using dialysis fluids with 1.36% and 2.27% glucose overnight reduces glucose exposure, but those schedules may provide inadequate UF and small-solute removal in some patients (UF < 1 L daily, Kt/V < 1.7).

NT-proBNP, fluid volume overload and dialysis modality are independent predictors of mortality in ESRD patients.

BACKGROUND: N-terminal fragment of B-type natriuretic peptide (NT-proBNP) is a marker of both fluid volume overload and myocardial damage, and it has been useful as a predictor of mortality in patients with end-stage renal disease (ESRD). It has been suggested that continuous ambulatory peritoneal dialysis (CAPD), automated peritoneal dialysis (APD) and haemodialysis (HD) may have different effects on fluid volume and blood pressure control; however, whether the independent predictive value of NT-proBNP for mortality is preserved when analysed in conjunction with fluid overload and dialysis modality is not clear. METHODS: A prospective multicentre cohort of 753 prevalent adult patients on CAPD, APD and HD was followed up for 16 months. Plasmatic levels of NT-proBNP, extracellular fluid volume/total body water ratio (ECFv/TBW) and traditional clinical and biochemical markers for cardiovascular damage risk were measured, and their role as predictors of all-cause and cardiovascular mortality was analysed. RESULTS: NT-proBNP level, ECFv/TBW and other cardiovascular damage risk factors were not evenly distributed among the different dialysis modalities. NT-proBNP levels and ECFv/TBW were correlated with several inflammation, malnutrition and myocardial damage markers. Multivariate analysis showed that NT-proBNP levels and ECFv/TBW were predictors of both all-cause and cardiovascular mortality, independently of dialysis modality and the presence of other known clinical and biochemical risk factors. CONCLUSIONS: NT-proBNP is a reliable predictor of death risk independently of the effect of dialysis modality on fluid volume control, and the presence of other clinical and biochemical markers recognized as risk factors for all-cause and cardiovascular mortality. NT-pro-BNP is a good predictor of mortality independently of fluid volume overload and dialysis modality.

Icodextrin improves metabolic and fluid management in high and high-average transport diabetic patients.

BACKGROUND: Icodextrin-based solutions (ICO) have clinical and theoretical advantages over glucose-based solutions (GLU) in fluid and metabolic management of diabetic peritoneal dialysis (PD) patients; however, these advantages have not yet been tested in a randomized fashion. OBJECTIVE: To analyze the effects of ICO on metabolic and fluid control in high and high-average transport diabetic patients on continuous ambulatory PD (CAPD). PATIENTS AND METHODS: A 12-month, multicenter, open-label, randomized controlled trial was conducted to compare ICO (n = 30) versus GLU (n = 29) in diabetic CAPD patients with high-average and high peritoneal transport characteristics. The basic daily schedule was 3 x 2 L GLU (1.5%) and either 1 x 2 L ICO (7.5%) or 1 x 2 L GLU (2.5%) for the long-dwell exchange, with substitution of 2.5% or 4.25% for 1.5% GLU being allowed when clinically necessary. Variables related to metabolic and fluid control were measured each month. RESULTS: Groups were similar at baseline in all measured variables. More than 66% of the patients using GLU, but only 9% using ICO, needed prescriptions of higher glucose concentration solutions. Ultrafiltration (UF) was higher (198 +/- 101 mL/day, p < 0.05) in the ICO group than in the GLU group over time. Changes from baseline were more pronounced in the ICO group than in the GLU group for extracellular fluid volume (0.23 +/- 1.38 vs -1.0 +/- 1.48 L, p < 0.01) and blood pressure (systolic 1.5 +/- 24.0 vs -10.4 +/- 30.0 mmHg, p < 0.01; diastolic 1.5 +/- 13.5 vs -6.2 +/- 14.2 mmHg, p < 0.01). Compared to baseline, patients in the ICO group had better metabolic control than those in the GLU group: glucose absorption was more reduced (-17 +/- 44 vs -64 +/- 35 g/day) as were insulin needs (3.6 +/- 3.4 vs - 9.1 +/- 4.7 U/day, p < 0.01), fasting serum glucose (8.3 +/- 36.5 vs -37 +/- 25.8 mg/dL, p < 0.01), triglycerides (54.5 +/- 31.9 vs -54.7 +/- 39.9 mg/dL, p < 0.01), and glycated hemoglobin (0.79% +/- 0.79% vs -0.98% +/- 0.51%, p < 0.01). Patients in the ICO group had fewer adverse events related to fluid and glucose control than patients in the GLU group. CONCLUSION: Icodextrin represents a significant advantage in the management of high transport diabetic patients on PD, improving peritoneal UF and fluid control and reducing the burden of glucose overexposure, thereby facilitating metabolic control.

Inflammation and extracellular volume expansion are related to sodium and water removal in patients on peritoneal dialysis.

BACKGROUND: Inflammation is an important risk for mortality in dialysis patients. Extracellular fluid volume (ECFv) expansion, a condition commonly seen in peritoneal dialysis (PD) patients, may be associated with inflammation. However, published support for this relationship is scarce. OBJECTIVES: To quantify the proportion of patients on PD with inflammation and to analyze the role of ECFv expansion and the factors related to these conditions. DESIGN: A prospective, multicenter cross-sectional study in six hospitals with a PD program. PATIENTS AND METHODS: Adult patients on PD were studied. Clinical data, body composition, and sodium and fluid intake were recorded. Biochemical analysis, C-reactive protein (CRP), and peritoneal and urinary fluid and sodium removal were also measured. RESULTS: CRP values positive (>or=3.0 mg/L) for inflammation were found in 147 (80.3%) and negative in 36 patients. Patients with positive CRP had higher ECFv/total body water (TBW) ratio (women 47.69 +/- 0.69 vs 47.36 +/- 0.65, men 43.15 +/- 1.14 vs 42.84 +/- 0.65; p < 0.05), higher serum glucose (125.09 +/- 81.90 vs 103.28 +/- 43.30 mg/dL, p < 0.03), and lower serum albumin (2.86 +/- 0.54 vs 3.17 +/- 0.38 g/dL, p < 0.001) levels. They also had lower ultrafiltration (1003 +/- 645 vs 1323 +/- 413 mL/day, p < 0.005) and total fluid removal (1260 +/- 648 vs 1648 +/- 496 mL/day, p < 0.001), and less peritoneal (15.59 +/- 162.14 vs 78.11 +/- 110.70 mEq/day, p < 0.01) and total sodium removal (42.06 +/- 142.49 vs 118.60 +/- 69.73 mEq/day, p < 0.001). In the multivariate analysis, only ECFv/TBW was significantly (p < 0.04) and independently associated with inflammation. ECFv/TBW was correlated with fluid removal (r = 0.16, p < 0.03) and renal sodium removal (r = 0.2, p < 0.01). CONCLUSION: The data suggest that ECFv expansion may have a significant role as an inflammatory stimulus. The results disclose a relationship between the two variables, ECFv expansion and inflammation, identified as independent risk factors for mortality in PD patients.

Effect of parathyroidectomy on cardiac fibrosis and apoptosis: possible role of aldosterone.

BACKGROUND/AIM: It has been demonstrated that parathyroidectomy prevents left ventricular hypertrophy in uremic animals. Although this effect may be mediated by direct actions of parathormone (PTH), it may also be exerted through regulation of profibrotic factors such as aldosterone. In adrenal cortex cell cultures, PTH increases aldosterone release. The objective of this work is to assess the effect of parathyroidectomy on aldosterone levels and on cardiac fibrosis and apoptosis in uremic rats. METHODS: Four groups of rats were studied: C, control; 5/6Nx, 5/6 nephrectomy; PTx, parathyroidectomy, and 5/6NxPTx, 5/6 nephrectomy plus parathyroidectomy. Thirty days after the last surgical procedure the animals were sacrificed. Serum creatinine, ionized calcium, aldosterone, PTH, cardiac weight, fibrosis and apoptosis were measured. RESULTS: Serum creatinine levels were significantly higher in 5/6Nx and 5/6NxPTx groups (1.62 +/- 0.21 and 1.38 +/- 0.15 mg/dl) than in C and PTx groups (0.66 +/- 0.02 and 0.47 +/- 0.01 mg/dl, p < 0.001). Potassium levels were significantly higher in the 5/6Nx and 5/6NxPTx groups (5.2 +/- 0.3 and 5.4 +/- 0.3 mg/dl) than in the C group (4.3 +/- 0.06 mg/dl, p < 0.05). Values in 5/6Nx and 5/6NxPTx groups were not significantly different from each other. PTH levels were significantly higher in the 5/6Nx group (470.5 +/- 156.3 microg/ml) than in the controls (102.3 +/- 14.3 microg/ml). PTH levels in the PTx group (1.78 +/- 0.52 microg/ml) and in the 5/6NxPTx group (81.64 +/- 32.15 microg/ml) were similar to control values. Ionized calcium was lower in PTx and 5/6NxPTx groups (0.80 +/- 0.07 and 0.89 +/- 0.07 mmol/l) as compared with C and 5/6Nx groups (1.14 +/- 0.01 and 0.96 +/- 0.01 mmol/ l, p < 0.01). The heart weight as percentage of the body weight increased significantly in 5/6Nx animals (4.20 +/- 0.15%) compared to the C group (3.41 +/- 0.27%, p < 0.05); parathyroidectomy reversed the heart weight increment in the 5/6NxPTx animals (3.58 +/- 0.16%). Myocardial fibrosis was significantly higher in the 5/6Nx group (12.5 +/- 1.1%) than in the C group (7.3 +/- 1.5%, p < 0.001); in the 5/6NxPTx animals fibrosis returned towards control values (8.9 +/- 0.2%). Myocardial apoptosis rose significantly in 5/6Nx animals (24.3 +/- 1.2%) compared to the C group (6.7 +/- 0.83%, p < 0.001); parathyroidectomy reversed the apoptosis in the 5/6NxPTx animals (10.4 +/- 0.49%). Aldosterone levels increased significantly in the 5/6Nx group (2,461 +/- 257 pg/ml) compared to the C group (703 +/- 81 pg/ml, p < 0.001); in the 5/6NxPTx animals aldosterone levels were below control values (509 +/- 99 pg/ml). CONCLUSIONS: Uremia was associated to myocardial hypertrophy, fibrosis and apoptosis. Surgically induced hypoparathyroidism prevented the development of these disorders. Our results suggest that in the remnant kidney rat model myocardial hypertrophy, fibrosis, and apoptosis are mediated by high circulating aldosterone levels. Aldosterone, in turn, may be regulated by PTH.