Pruritus in dialysis patients. Review and new perspectives.

Uremic pruritus (UP) is one of the most uncomfortable symptoms for patients in dialysis. UP has a great impact on dialysis patients' quality of life and has a great prevalence between those (28-70%). Physiopathology of UP is unknown and usually is unnoticed for most nephrologists (in more than 65% of centers is underdiagnosed). This lack of awareness drives to the unsuccessful treatment of this symptom. Moreover, the fact that most studies have been carried out on small populations and the difficulty assessing UP complicates a correct therapeutical approach. For this reason, we have designed treatment algorithms based on the efficacy of the drugs but also its safeness to avoid adverse effects.

Prurito en pacientes en diálisis. Revisión de la literatura y nuevas perspectivas / Pruritus in dialysis patients. Review and new perspectives

El prurito es uno de los síntomas más incómodos y que más impacta en la calidad de vida de los pacientes en diálisis. Su prevalencia es bastante elevada en pacientes en diálisis (28-70%). La fisiopatología del prurito urémico es desconocida, y este síntoma a menudo pasa desapercibido para el personal sanitario, siendo infradiagnosticado en más del 65% de los centros. Esta falta de reconocimiento deriva en un abordaje terapéutico ineficaz del prurito urémico. Por otro lado, la mayoría de los ensayos farmacológicos para el tratamiento del prurito urémico han sido realizados en poblaciones reducidas y están sujetos a la subjetiva medición del propio síntoma. Por este motivo, hemos propuesto algoritmos de tratamiento, teniendo en cuenta la evidencia que avala a cada fármaco y a la vez la pluripatología y la polifarmacia de cada paciente, con el fin de evitar efectos adversos. (AU)

Uremic pruritus (UP) is one of the most uncomfortable symptoms for patients in dialysis. UP has a great impact on dialysis patients’ quality of life and has a great prevalence between those (28–70%). Physiopathology of UP is unknown and usually is unnoticed for most nephrologists (in more than 65% of centers is underdiagnosed). This lack of awareness drives to the unsuccessful treatment of this symptom. Moreover, the fact that most studies have been carried out on small populations and the difficulty assessing UP complicates a correct therapeutical approach. For this reason, we have designed treatment algorithms based on the efficacy of the drugs but also its safeness to avoid adverse effects. (AU)

Pruritus in dialysis patients. Review and new perspectives. / Prurito en pacientes en diálisis. Revisión de la literatura y nuevas perspectivas.

Uremic pruritus (UP) is one of the most uncomfortable symptoms for patients in dialysis. UP has a great impact on dialysis patients' quality of life and has a great prevalence between those (28-70%). Physiopathology of UP is unknown and usually is unnoticed for most nephrologists (in more than 65% of centers is underdiagnosed). This lack of awareness drives to the unsuccessful treatment of this symptom. Moreover, the fact that most studies have been carried out on small populations and the difficulty assessing UP complicates a correct therapeutical approach. For this reason, we have designed treatment algorithms based on the efficacy of the drugs but also its safeness to avoid adverse effects.

Hernia de Morgagni en diálisis peritoneal incremental: ¿es posible continuar con la técnica? / Morgagni hernia in incremental peritoneal dialysis: Is it possible to continue with the technique?

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A case-control study to assess the role of polyomavirus in transplant complications: Where do we stand?

PURPOSE: The study's aim was to assess whether polyomavirus DNAemia screening was associated with different outcomes in patients with positive viremia compared with negative viremia. METHODS: Case-control retrospective study of patients with polyomavirus DNAemia (viremia > 1000 copies/mL) matched 1:1 with controls. Control group consists of the patient who received a transplant immediately before or after each identified case and did have nil viremia. FINDING: Ultimately, 120 cases of BK polyomavirus (BKPyV) were detected and matched with 130 controls. Of these, 54 were adult kidney transplant recipients (KTRs), 43 were pediatric KTRs, and 23 were undergoing hemato-oncologic therapy, of which 20 were undergoing hematopoietic stem cell transplantation. The odds ratio (OR) for overall risk of poorer outcomes in cases versus controls was 16.07 (95% CI: 5.55-46.54). The unfavorable outcome of switching the immunosuppressive drug (ISD) (14/40,35%) was no different from that of those treated with reduced ISD doses (31/71, 43.6%, P = .250). Acute rejection or graft-versus-host disease, previous transplant, and intensity of immunosuppression (4 ISDs plus induction or conditioning) were risk factors for BKPyV-DNAemia (OR: 13.96, 95% CI: 11.25-15.18, P < .001; OR: 6.14, 95% CI: 3.91-8.80, P < .001; OR: 5.53, 95% CI: 3.37-7.30, P < .001, respectively). CONCLUSIONS: Despite viremia screening, dose reduction, and change in therapeutic protocol, patients with positive BKPyV-DNAemia present poorer outcomes and unfavorable results.

Eficacia de la creación de un programa de Escuela de pacientes en la detección de necesidades en pacientes con Poliquistosis Renal Autosómica Dominante / Efficacy of the creation of a patient school program in the detection of needs in patients with autosomal dominant polycystic kidney disease

Introducción: La Poliquistosis Renal Autosómica Dominante es una enfermedad renal crónica responsable del 10% de los casos de insuficiencia renal terminal. La participación y los grupos de apoyo entre iguales son herramientas que mejoran el bienestar, evitando complicaciones y retrasando el avance de la enfermedad. Objetivos: Detectar necesidades informativas, así como recursos de apoyo, en este grupo de pacientes mediante la puesta en marcha de una Escuela de Pacientes con poliquistosis renal autosómica dominante. Material y Método: Se utilizó un diseño mixto (cuantitativo y cualitativo). El estudio se desarrolló mediante cuatro fases: 1) Grupo focal: pacientes con poliquistosis renal y sus cuidadores; 2) Selección de los pacientes expertos; 3) Elaboración de los contenidos del programa de la Escuela de pacientes con poliquitstosis renal autosómica dominante; 4) Pilotaje del programa. Resultados: Se detectaron necesidades de información referentes al tratamiento oral y al afrontamiento de la poliquistosis renal que no están cubiertas por los equipos de nefrología. Conclusiones: La Escuela de Pacientes ha demostrado ser una herramienta útil para detectar necesidades y recursos en pacientes con poliquistosis renal autosómica dominante que han de enfrentarse a una enfermedad crónica donde se requiere la participación del paciente para garantizar la adhesión al tratamiento

Introduction: Autosomal Dominant Polycystic Kidney Disease is a chronic kidney disease responsible for 10% of cases of end-stage renal failure. Participation and peer support groups are tools that improve well-being, avoiding complications and delaying disease progression. Objectives: To detect information needs, as well as support resources, in patients with autosomal dominant polycystic kidney disease trough a Patient School. Material and Method: A mixed design (quantitative and qualitative) was used. The study was developed through four phases: 1) Focus group: patients with autosomal dominant polycystic kidney disease and their caregivers; 2) Selection of expert patients; 3) Preparation of the contents of the program of the Patient School with autosomal dominant polycystic kidney disease; 4) Piloting the program. Results: Information needs regarding oral treatment and coping with autosomal dominant polycystic kidney disease were detected, which are not covered by nephrology teams. Conclusions: Patients School has proven to be a useful tool to detect needs and resources in patients with autosomal dominant polycystic kidney disease who have to face a chronic disease where patient participation is required to ensure adherence to treatment

[Assessment of diet in patients with chronic kidney diseases without dialysis and relationship with the nutritional status]. / Evaluación de la dieta en pacientes con enfermedad renal crónica sin diálisis y su relación con el estado nutricional.

BACKGROUND: Diet is one of the pillars of the treatment for patients with chronic kidney disease without dialysis (NDD-CKD). Despite this, very few studies have evaluated the diet in Spanish population. OBJECTIVE: To evaluate the diet of a group of patients with advanced CKD, comparing it with the recommendations, and its relation with nutritional status. MATERIAL AND METHODS: A cross-sectional study of 74 patients (39 men), with a mean age of 70.9 ± 13.6 years and creatinine clearance of 15.3 ± 2.1 mL/min. Biochemical, anthropometric and intake variables (3-day dietary record) were collected, comparing them with the recommendations for patients with CKD and, if they did not exist, with nutritional recommendations and objectives for the Spanish population. The nutritional status was assessed by modified criteria of protein-energy wasting (PEW). RESULTS: The mean energy intake was 23.2 ± 6.5 kcal/kg body weight/day, and the protein intake was 0.93 ± 0.2 g/kg body weight/day. Men had a higher intake of alcohol and vitamin D whereas women presented a higher intake of trans fatty acids and vitamin B1. In addition, 91.4% of patients had high intake of phosphorus and 73% of potassium. Only 2.7% showed an adequate intake of vitamin D and 21.6% of folates; 18.9% of patients presented PEW. A positive correlation was found between albumin, body mass index (BMI) and creatinine clearance. CONCLUSION: Most patients with non-dialysis CKD do not meet dietary recommendations or nutritional goals, regardless of gender and PEW status, considering renal function as a limiting factor.

Evaluación de la dieta en pacientes con enfermedad renal crónica sin diálisis y su relación con el estado nutricional / Assessment of diet in patients with chronic kidney diseases without dialysis and relationship with the nutritional status

Introducción: la dieta en los pacientes con enfermedad renal crónica (ERC) sin diálisis es uno de los pilares de su tratamiento. A pesar de esto existen muy pocos estudios que hayan evaluado la dieta en esta población y ninguno en población española. Objetivo: evaluar la dieta de un colectivo de pacientes con ERC avanzada, comparándola con las recomendaciones, y su relación con marcadores del estado nutricional. Material y métodos: estudio transversal de 74 pacientes (39 hombres), con edad media de 70,9 ± 13,6 años y aclaramiento de creatinina 15,3 ± 2,1 mL/min. Se recogieron variables bioquímicas, antropométricas y de ingesta (registro dietético de tres días), que fueron comparadas con las recomendaciones para pacientes con ERC y, si no existían, con las recomendaciones y objetivos nutricionales para población española. Se valoró el estado nutricional mediante criterios modificados de desgaste proteico energético (DPE). Resultados: la ingesta energética media fue de 23,2 ± 6,5 kcal/kg peso/día y la ingesta proteica, de 0,93 ± 0,2 g/kg peso/día. Los hombres presentaban una ingesta mayor de alcohol y vitamina D y las mujeres, de ácidos grasos trans y vitamina B1. Un 91,4% presentaba ingesta elevada de fósforo y un 73%, de potasio. Solo el 2,7% presentaba ingesta adecuada de vitamina D y el 21,6%, de folatos. El 18,9% presentaba DPE. Se encontró una correlación positiva entre albúmina, índice de masa corporal (IMC) y aclaramiento de creatinina. Conclusión: la mayoría de los pacientes con ERC sin diálisis no cumplen las recomendaciones de ingesta ni los objetivos nutricionales, independientemente del sexo y de la situación de DPE, considerando la función renal como un factor limitante (AU)

Background: Diet is one of the pillars of the treatment for patients with chronic kidney disease without dialysis (NDD-CKD). Despite this, very few studies have evaluated the diet in Spanish population. Objective: To evaluate the diet of a group of patients with advanced CKD, comparing it with the recommendations, and its relation with nutritional status. Material and methods: A cross-sectional study of 74 patients (39 men), with a mean age of 70.9 ± 13.6 years and creatinine clearance of 15.3 ± 2.1 mL/min. Biochemical, anthropometric and intake variables (3-day dietary record) were collected, comparing them with the recommendations for patients with CKD and, if they did not exist, with nutritional recommendations and objectives for the Spanish population. The nutritional status was assessed by modified criteria of protein-energy wasting (PEW). Results: The mean energy intake was 23.2 ± 6.5 kcal/kg body weight/day, and the protein intake was 0.93 ± 0.2 g/kg body weight/day. Men had a higher intake of alcohol and vitamin D whereas women presented a higher intake of trans fatty acids and vitamin B1. In addition, 91.4% of patients had high intake of phosphorus and 73% of potassium. Only 2.7% showed an adequate intake of vitamin D and 21.6% of folates; 18.9% of patients presented PEW. A positive correlation was found between albumin, body mass index (BMI) and creatinine clearance. Conclusion: Most patients with non-dialysis CKD do not meet dietary recommendations or nutritional goals, regardless of gender and PEW status, considering renal function as a limiting factor (AU)

[Bioimpedance vector analysis as a tool for the determination and adjustment of dry weight in patients undergoing hemodialysis]. / VECTORES DE IMPEDANCIA BIOELÉCTRICA COMO HERRAMIENTA PARA LA DETERMINACIÓN Y AJUSTE DEL PESO SECO EN PACIENTES SOMETIDOS A HEMODIÁLISIS.

BACKGROUND AND OBJECTIVE: Overhydration in hemodialysis patients is associated with cardiovascular mortality. Adequate removal of liquids and achievement of dry weight is one of the main goals of therapy. So far there are no clinical or laboratory parameters that are reliable, simple and affordable for its determination. The bioelectrical impedance vector analysis (BIVE) is a tool that allows identifying and monitoring hydration status, so the aim of this study was to use BIVE to adjust the intensity of ultrafiltration and achieve dry weight in hemodialysis patients. METHODS: We studied 26 patients on hemodialysis, which were performed monthly measurements of bioelectrical impedance for four months. Corresponding vectors were plotted to know in an individual way the state of hydration, according to which the dry weight was adjusted when necessary. RESULTS: Dry weight adjustment was performed in 13 patients, 7 of which required increase and 6 decrease of dry weight. The displacement of vectors on the ellipses corresponded to the type of intervention made. Dry weight was reached in 84.6% of patients at the end of the study with a significant decrease in mean arterial blood pressure and an increase in phase angle in the group of decrease of dry weight. CONCLUSIONS: Bioelectrical impedance vector analysis is an useful tool for adjusting the dry weight in patients undergoing hemodialysis.

Antecedentes y objetivo: La sobrehidratación en los pacientes en hemodiálisis se asocia con mortalidad cardiovascular, por lo que la adecuada remoción de líquidos y el logro del peso seco es uno de los principales objetivos de la terapia. Hasta el momento no hay parámetros clínicos ni de laboratorio que sean confiables, sencillos y accesibles para su determinación. El análisis de vectores de impedancia (VIBE) es una herramienta que permite identificar y monitorizar el estado de hidratación, por lo que el objetivo de este estudio fue usar el VIBE para ajustar la intensidad del ultrafiltrado y alcanzar el peso seco en pacientes en hemodiálisis. Material y método: Se estudiaron 26 pacientes en hemodiálisis a los cuales se les realizaron medidas mensuales de impedancia bioeléctrica durante cuatro meses. Se graficaron los vectores correspondientes para conocer de manera individual el estado de hidratación, de acuerdo con lo cual se ajustó el peso seco en los casos necesarios. Resultados: Se realizó ajuste de peso seco en 13 pacientes, 7 de ellos necesitaron aumento de peso y 6 disminución del mismo. El desplazamiento de los vectores sobre las elipses correspondió al tipo de intervención realizada. Se logró alcanzar el peso seco en el 84.6% de los pacientes al final del estudio, con una disminución significativa de la presión arterial media y aumento del ángulo de fase en el grupo de disminución de peso seco. Conclusiones: El análisis de vectores de impedancia es útil para el ajuste del peso seco en los pacientes sometidos a hemodiálisis.

Vectores de impedancia bioeléctrica como herramienta para la determinación y ajuste del peso seco en pacientes sometidos a hemodiálisis / Bioimpedance vector analysis as a tool for the determination and adjustment of dry weight in patients undergoing hemodialysis

Antecedentes y objetivo: La sobrehidratación en los pacientes en hemodiálisis se asocia con mortalidad cardiovascular, por lo que la adecuada remoción de líquidos y el logro del peso seco es uno de los principales objetivos de la terapia. Hasta el momento no hay parámetros clínicos ni de laboratorio que sean confiables, sencillos y accesibles para su determinación. El análisis de vectores de impedancia (VIBE) es una herramienta que permite identificar y monitorizar el estado de hidratación, por lo que el objetivo de este estudio fue usar el VIBE para ajustar la intensidad del ultrafiltrado y alcanzar el peso seco en pacientes en hemodiálisis. Material y método: Se estudiaron 26 pacientes en hemodiálisis a los cuales se les realizaron medidas mensuales de impedancia bioeléctrica durante cuatro meses. Se graficaron los vectores correspondientes para conocer de manera individual el estado de hidratación, de acuerdo con lo cual se ajustó el peso seco en los casos necesarios. Resultados: Se realizó ajuste de peso seco en 13 pacientes, 7 de ellos necesitaron aumento de peso y 6 disminución del mismo. El desplazamiento de los vectores sobre las elipses correspondió al tipo de intervención realizada. Se logró alcanzar el peso seco en el 84.6% de los pacientes al final del estudio, con una disminución significativa de la presión arterial media y aumento del ángulo de fase en el grupo de disminución de peso seco. Conclusiones: El análisis de vectores de impedancia es útil para el ajuste del peso seco en los pacientes sometidos a hemodiálisis (AU)

Background and objective: Overhydration in hemodialysis patients is associated with cardiovascular mortality. Adequate removal of liquids and achievement of dry weight is one of the main goals of therapy. So far there are no clinical or laboratory parameters that are reliable, simple and affordable for its determination. The bioelectrical impedance vector analysis (BIVE) is a tool that allows identifying and monitoring hydration status, so the aim of this study was to use BIVE to adjust the intensity of ultrafiltration and achieve dry weight in hemodialysis patients. Methods: We studied 26 patients on hemodialysis, which were performed monthly measurements of bioelectrical impedance for four months. Corresponding vectors were plotted to know in an individual way the state of hydration, according to which the dry weight was adjusted when necessary. Results: Dry weight adjustment was performed in 13 patients, 7 of which required increase and 6 decrease of dry weight. The displacement of vectors on the ellipses corresponded to the type of intervention made. Dry weight was reached in 84.6% of patients at the end of the study with a significant decrease in mean arterial blood pressure and an increase in phase angle in the group of decrease of dry weight. Conclusions: Bioelectrical impedance vector analysis is an useful tool for adjusting the dry weight in patients undergoing hemodialysis (AU)

Comentario a «Análisis de costes y perfil sociocultural del enfermo renal. Impacto de la modalidad de tratamiento» / Comment on "Cost analysis and sociocultural profile of kidney patients. Impact of the treatment method"

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Evaluación del impacto de cartas de condolencia en familiares en duelo / Assessment of the impact of condolence letters on bereaved families

OBJETIVOS: Evaluar el impacto emocional y la utilidad percibida de las cartas de condolencia en familiares de pacientes fallecidos en los servicios de nefrología y hematología. MÉTODO: Estudio prospectivo con una única medida en forma de entrevista telefónica semiestructurada. Cuestionario elaborado ad hoc. Las variables se evaluaban de forma independiente. La muestra consta 102 muertes y 82 dolientes. RESULTADOS: Un 15% de la muestra refiere haber sentido malestar al recibir la carta y el 100% de la muestra sintió bienestar (categorías no excluyentes), con emociones como gratitud (42,5%), alegría (40%), orgullo (10%) y sorpresa (7,5%). El 96,3% compartió la carta con el entorno. El 98,8% refiere que la carta le ha sido útil. Los pacientes renales son mayores en el momento del fallecimiento (U = 599,00; p < 0,001), han pasado más años en seguimiento por el servicio (χ2 = 19,40; p < 0,001) y responden con mayor frecuencia a la carta de condolencia a través de llamadas telefónicas, visitas al servicio o tarjetas postales (χ2 = 5,30; p < 0,001). No se han encontrado diferencias estadísticamente significativas en relación con los resultados del impacto de la carta entre los familiares de los 2 servicios. DISCUSIÓN: El impacto de la carta ha producido bienestar en todos los familiares y malestar en un 15% de la muestra. Se impone la necesidad de considerar en el duelo emociones opuestas pero no incompatibles. Conocer esta ambivalencia propia de los procesos de pérdida ayudará a la normalización de la misma

OBJECTIVES: To assess the emotional impact and perceived usefulness of condolence letters in families of patients who died in the hospital Nephrology and Haematology departments. Method: A prospective study was conducted with a single one measure in the form of a semistructured telephone interview. The questionnaire was constructed ad hoc. Variables were assessed independently. The sample consisted of 102 deceased and 82 grievers. RESULTS: Of the total responses 15% related to have felt discomfort on receiving the letter and100% of the sample (non-exclusive percentages) were comforted, reporting emotions such as, gratitude (42.5%) happiness (40%), pride (10%), and surprise (7.5%). The large majority (96.3%)shared the letter with those around them, and 98.8% said that the letter was useful. The patients with kidney disease were older at time of death (U = 599.00; P=.008), were attended for more years in the department (2 = 19. ,40; P<.001) and their families responded more frequently to the condolence letter through phone calls, visits to the department, or by post card (2 = 5.30;P<.021). The difference between the results of the impact of the letter on both departments was not statistically significant. DISCUSSION: The impact of the letter gave comfort to all the families, and discomfort in 15%of the sample. It shows the need to consider the opposite, but not incompatible emotions, in bereavement. Awareness of this ambivalence, which is typical in the grieving process, will help to normalise it

Experiencia de 30 años en una unidad de diálisis peritoneal: supervivencia a largo plazo / Thirty years in a peritoneal dialysis unit: long-term survival

INTRODUCCIÓN: La diálisis peritoneal (DP) es una técnica establecida de tratamiento renal sustitutivo que gracias a los avances tecnológicos y clínicos ha mejorado sus tasas de supervivencia en los últimos años. OBJETIVOS: Evaluar la supervivencia del paciente y la técnica en DP a lo largo de 30 años y según las décadas para consolidar su utilidad sanitaria. MÉTODOS: Estudio retrospectivo de cohorte de todos los pacientes del programa de DP del Hospital Universitario La Paz (Madrid) desde 1980 a 2010. Variables demográficas y clínicas fueron recolectadas de los registros clínicos. RESULTADOS: Se incluyeron 667 pacientes, 54,4 % varones, con edad media de 51,47 años y una mediana de seguimiento de 23,1 meses. Se observó un aumento progresivo de pacientes incidentes, especialmente en DP automatizada (DPA). La supervivencia del paciente a 5 años fue de 54 %, con una mediana de 64,66 meses, con un aumento significativo en la última década (p = 0,000). La edad, la comorbilidad, el sexo masculino, la DP crónica ambulatoria (DPCA) y la diabetes fueron predictores de la supervivencia del paciente. La supervivencia de la técnica a los 5 años fue del 64,2 % y la mediana de 82 meses. El éxito de la técnica fue mayor en jóvenes, en DPA y con menor comorbilidad

BACKGROUND AND OBJECTIVE: Peritoneal dialysis (PD) is an establish renal replacement therapy that has evolved in the last decades thanks to technological and clinical advances showing improving survival rates. The aim of this study was to evaluate the patient and technique survival in PD over 30 years of experience and in the different decades. PATIENTS AND METHOD: Retrospective cohort study including all patients in the PD unit of the Hospital Universitario La Paz (Madrid), from 1980 to 2010. Demographics and clinical variables were collected from medical records. RESULTS: A total of 667 patients were included, 54.4% males, with a mean age of 51.47 years and a median follow-up of 23.1 months. There was an increased in PD incident patients, especially in automatic PD (APD). Patient survival at 5 years was 54%, with a median of 64.66 months, increasing significantly in the last decade (p = 0.000). Age, comorbidity, male sex, chronic ambulatory PD and diabetes were independently predictor of patient survival. Technique survival at 5 years was 64.2% and median 82 months. Younger patients, in APD and with less comorbity showed better technique survival. CONCLUSIONS: Over 30 years of experience we found an increased in incident patients. Age, comorbidity and diabetes were still the main predictors of survival

Thirty years in a peritoneal dialysis unit: long-term survival.

INTRODUCTION: Peritoneal dialysis (PD) is an established renal replacement therapy technique which thanks to the technological and clinical advances has improved its survival rates in recent years. OBJECTIVES: The aim of this study was to evaluate patient and technique survival in PD over 30 years, according to the different decades in order to consolidate its usefulness in healthcare. METHOD: Retrospective cohort study including all patients in the PD programme of the Hospital Universitario La Paz (Madrid), from 1980 to 2010. Demographic and clinical variables were collected from medical records. RESULTS: A total of 667 patients were included, 54.4% male, with a mean age of 51.47 years and a median follow-up period of 23.1 months. There was a progressive increase in PD incident patients, especially in automated PD (APD). Patient survival at 5 years was 54%, with a median of 64.66 months, increasing significantly in the last decade (P=.000). Age, comorbidity, male sex, chronic ambulatory PD (CAPD) and diabetes were predictors of patient survival. Technique survival at 5 years was 64.2% with a median of 82 months. The success of the technique was greater in younger patients on APD and with lower comorbidity. CONCLUSIONS: Over 30 years, we found an increase in incident patients. Age, comorbidity and diabetes still continue to be the main determining factors for survival.