Concentraciones más elevadas de fósforo sérico en pacientes con enfermedad renal crónica avanzada tratados con diuréticos / Increased serum phosphate concentrations in patients with advanced chronic kidney disease treated with diuretics

INTRODUCCIÓN: Las concentraciones séricas de fósforo muestran una gran variabilidad en los pacientes con enfermedad renal crónica avanzada (ERCA) no en diálisis. El tratamiento con diuréticos puede influir en la severidad de las alteraciones óseo-minerales relacionadas con la ERCA, pero su efecto sobre los niveles de fósforo sérico es menos conocido. OBJETIVOS: Determinar si existe una asociación independiente entre los niveles de fósforo sérico y el tratamiento con diuréticos, e investigar los mecanismos por los que los diuréticos podrían afectar el metabolismo del fósforo. MATERIAL Y MÉTODOS: Estudio transversal en el que fueron incluidos 429 pacientes con ERCA. Además de las determinaciones analíticas convencionales, se incluyeron los siguientes parámetros: excreción urinaria de fósforo en 24 horas, reabsorción tubular máxima de fósforo (TmP) y fracción de excreción de fósforo (FEP). RESULTADOS: El 55 % de los pacientes estaba en tratamiento con diuréticos. Con respecto a los no tratados con diuréticos, los que recibieron este tratamiento mostraron una concentración media de fósforo sérico significativamente superior (4,78 ± 1,23 vs. 4,24 ± 1,04 mg/dl; p < 0,0001), así como una mayor TmP (2,77 ± 0,72 vs. 2,43 ± 0,78 mg/dl; p < 0,0001). Por regresión lineal y logística múltiple, las asociaciones entre diuréticos y concentraciones de fósforo sérico o hiperfosfatemia (fósforo sérico > 4,5 mg/dl) mantuvieron las significaciones estadísticas tras ajuste con las principales variables confundentes. En los pacientes con la máxima carga de fósforo ajustada a función renal, aquellos tratados con diuréticos mostraron una FEP significativamente menor que los no tratados con diuréticos. CONCLUSIÓN: El tratamiento con diuréticos en la ERCA se asocia a concentraciones más elevadas de fósforo sérico. Los diuréticos podrían interferir de forma indirecta con la máxima capacidad compensatoria renal de excretar fósforo. El tratamiento con diuréticos debería ser tenido en cuenta en los estudios que relacionan las concentraciones de fósforo sérico y las alteraciones cardiovasculares

BACKGROUND: Serum phosphate concentrations usually show great variability in patients with advanced chronic kidney disease (CKD) not requiring dialysis. Diuretics can alter mineral metabolism, and according to previous clinical observations, they may increase serum phosphate levels. OBJECTIVES: This study aims to confirm whether diuretics are independently associated with increased serum phosphate concentrations, and to investigate by which mechanisms diuretics may affect phosphate metabolism. METHODS: In this cross-sectional, singlecentre study, 429 Caucasian patients with advanced CKD not on dialysis were included. In addition to conventional serum biochemical measures, the following parameters of renal phosphate excretion were assessed: 24 hours urinary phosphate excretion, tubular maximum phosphate reabsorption (TmP) per GFR, and fractional excretion of phosphate (FEP). RESULTS: Fiftyeight percent of patients were on diuretics. Patients on diuretics showed significantly higher mean serum phosphate concentration (4.78±1.23 vs. 4.24±1.04mg/dl; p<.0001), and higher TmP per GFR (2.77±0.72 vs. 2.43±0.78mg/dl; p<.0001) than those of patients untreated with diuretics. By multivariate linear and logistic regression, significant associations between diuretics and serum phosphate concentrations or hyperphosphatemia remained after adjustment for potential confounding variables. In patients with the highest phosphate load weighted to kidney function, those treated with diuretics showed significantly lower FEP than that of patients untreated with diuretics. CONCLUSIONS: Diuretic treatment is associated with increased serum phosphate concentrations in patients with advanced CKD. Diuretics may indirectly interfere with the maximum renal compensatory capacity to excrete phosphate. Diuretics should be considered potential confounders in the relationship between serum phosphate concentrations and cardiovascular outcomes in patients with CKD

Increased serum phosphate concentrations in patients with advanced chronic kidney disease treated with diuretics.

BACKGROUND: Serum phosphate concentrations usually show great variability in patients with advanced chronic kidney disease (ACKD) not on dialysis. Diuretics treatment can have an influence over the severity of mineral-bone metabolism alterations related to ACKD, but their effect on serum phosphate levels is less known. OBJECTIVES: This study aims to determine whether diuretics are independently associated with serum phosphate levels, and to investigate the mechanisms by which diuretics may affect phosphate metabolism. MATERIAL AND METHOD: 429 Caucasian patients with CKD not on dialysis were included in this cross-sectional study. In addition to conventional serum biochemical measures, the following parameters of renal phosphate excretion were assessed: 24-hours urinary phosphate excretion, tubular maximum phosphate reabsorption (TmP), and fractional excretion of phosphate (FEP). RESULTS: 58% of patients were on treatment with diuretics. Patients on diuretics showed significantly higher mean serum phosphate concentration (4.78 ± 1.23 vs. 4.24 ± 1.04 mg/dl; P<.0001), and higher TmP per GFR (2.77 ± 0.72 vs. 2.43 ± 0.78 mg/dl; P<.0001) than those not treated with diuretics. By multivariate linear and logistic regression, significant associations between diuretics and serum phosphate concentrations or hyperphosphataemia remained after adjustment for potential confounding variables. In patients with the highest phosphate load adjusted to kidney function, those treated with diuretics showed significantly lower FEP than those untreated with diuretics. CONCLUSIONS: Treatment with diuretics is associated with increased serum phosphate concentrations in patients with ACKD. Diuretics may indirectly interfere with the maximum renal compensatory capacity to excrete phosphate. Diuretics should be considered in the studies linking the relationship between serum phosphate concentrations and cardiovascular alterations in patients with CKD.

Insuficiencia cardíaca en la enfermedad renal crónica avanzada: relación con el acceso vascular / Congestive heart failure in patients with advanced chronic kidney disease: association with pre-emptive vascular access placement

Introducción: La insuficiencia cardíaca congestiva (ICC) es una complicación frecuente en la enfermedad renal crónica (ERC). Además de los factores de riesgo clásicos, otros relacionados más específicamente con la ERC, como la anemia, la sobrehidratación o los accesos vasculares, también podrían jugar un papel importante. Objetivos: Determinar la incidencia y las características clínicas asociadas al desarrollo de ICC en pacientes con ERC avanzada y analizar la influencia de la creación de accesos vasculares prediálisis sobre esta complicación. Pacientes y métodos: Estudio de cohorte prospectivo y de observación en el que se incluyeron 562 pacientes (edad media 65 ± 15 años, 260 mujeres) con un filtrado glomerular medio de 15,1 ± 5,0 ml/min, no en diálisis. La variable de resultado principal fue el desarrollo de al menos un episodio de ICC definida por criterios clínicos y radiológicos convencionales. Además de los datos demográficos y clínicos de interés, se incluyó también como covariable la fístula arteriovenosa (FAV). Resultados: Con una mediana de seguimiento de 461 días, la incidencia de ICC fue de 19 episodios por cada 1000 pacientes/año, presentando esta complicación un 17% del total de los pacientes. Mediante regresión logística multivariable, los mejores determinantes del desarrollo de ICC fueron, además de los factores de riesgo clásicos (mujer, añosa, obesa, diabética, con antecedentes de cardiopatía), la realización con éxito de una FAV (odds ratio: 9,541; intervalo de confianza 95%: 4,841; 18,806; p < 0,0001). Mientras que 4 de los 51 pacientes (8%) con FAV distales desarrollaron ICC, 43 de los 109 pacientes (40%) con FAV proximales desarrollaron esta complicación. No se observaron diferencias en la mortalidad de los pacientes con o sin ICC, aunque el inicio no programado (urgente) de diálisis fue mucho más frecuente entre los que desarrollaron ICC que en el resto (63 vs. 3%, p < 0,0001). Conclusiones: La incidencia de ICC es muy elevada en pacientes con ERC avanzada prediálisis. Además de los factores de riesgo clásicos, la realización de un acceso vascular incrementa significativamente la probabilidad de desarrollo de esta complicación cardiovascular (AU)

Introduction: Congestive heart failure (CHF) is a common complication in patients with chronic kidney disease (CKD). In addition to classical risk factors (e.g. age and pre-existing cardiac diseases), other potential reversible abnormalities linked to CKD such as anaemia, volume overload, or vascular access placement may also influence the incidence and severity of acute exacerbations of CHF. Objective: This study aims to determine the incidence and main determinants of CHF in a cohort of patients with stage 4-5 pre-dialysis CKD. Patients and Method: The study group consisted of 562 patients (mean age: 65±15 years, 260 females, 31% diabetics). Native arteriovenous fistulas (AVF) were created in 160 patients who chose haemodialysis as the initial technique for renal replacement therapy. The main outcome variables were: acute decompensated CHF (defined by standard criteria), dialysis initiation (planned and unplanned), and death before dialysis initiation. In addition to demographics, comorbidities, and clinical and biochemical data, AVF creation was also included as a potential determinant of CHF in multiple logistic regression models. Results: Ninety-five patients (17%) developed at least one episode of acute decompensated CHF, and the incidence rate was 19 episodes per 1000 patient-years. In addition to classical risk factors (age, female sex, obesity, diabetes, and previous history of CHF or coronary artery disease), creation of a successful AVF significantly increased the risk of CHF (OR=9.54, 95% CI: 4.84-18.81, P<.0001). In 47 out of 95 patients who developed CHF, a functioning AVF had previously been created, 92% of which were upper arm native AVF, with a median of 51 days between the surgical procedure and CHF episode. The mortality of patients with CHF was similar to that of the rest of the study patients, although unplanned dialysis initiation was significantly more frequent in those who developed CHF. Conclusions: Acute decompensated CHF episodes are common in pre-dialysis CKD patients. In addition to classical risk factors, pre-emptive AVF placement was strongly associated with the development of CHF (AU)

Congestive heart failure in patients with advanced chronic kidney disease: association with pre-emptive vascular access placement.

INTRODUCTION: Congestive heart failure (CHF) is a common complication in patients with chronic kidney disease (CKD). In addition to classical risk factors (e.g. age and pre-existing cardiac diseases), other potential reversible abnormalities linked to CKD such as anaemia, volume overload, or vascular access placement may also influence the incidence and severity of acute exacerbations of CHF. OBJECTIVE: This study aims to determine the incidence and main determinants of CHF in a cohort of patients with stage 4-5 pre-dialysis CKD. PATIENTS AND METHOD: The study group consisted of 562 patients (mean age: 65 +/- 15 years, 260 females, 31% diabetics). Native arteriovenous fistulas (AVF) were created in 160 patients who chose haemodialysis as the initial technique for renal replacement therapy. The main outcome variables were: acute decompensated CHF (defined by standard criteria), dialysis initiation (planned and unplanned), and death before dialysis initiation. In addition to demographics, comorbidities, and clinical and biochemical data, AVF creation was also included as a potential determinant of CHF in multiple logistic regression models. RESULTS: Ninety-five patients (17%) developed at least one episode of acute decompensated CHF, and the incidence rate was 19 episodes per 1000 patient-years. In addition to classical risk factors (age, female sex, obesity, diabetes, and previous history of CHF or coronary artery disease), creation of a successful AVF significantly increased the risk of CHF (OR=9.54, 95% CI: 4.84-18.81, P<.0001). In 47 out of 95 patients who developed CHF, a functioning AVF had previously been created, 92% of which were upper arm native AVF, with a median of 51 days between the surgical procedure and CHF episode. The mortality of patients with CHF was similar to that of the rest of the study patients, although unplanned dialysis initiation was significantly more frequent in those who developed CHF. CONCLUSIONS: Acute decompensated CHF episodes are common in pre-dialysis CKD patients. In addition to classical risk factors, pre-emptive AVF placement was strongly associated with the development of CHF.