Inflammation and hemodialysis adequacy: are C-reactive protein levels influenced by the dose of dialysis?

INTRODUCTION: Chronic inflammation and the underlying cardiovascular comorbidity are still current problems in chronic hemodialysis patients. There are few studies comparing the "dialysis dose" with the degree of inflammation in the patient. Our main objective was to determine whether there is a relationship between serum C-reactive protein (CRP) levels and the "dialysis dose" (Kt / V) using ionic dialysance. METHODS: Multicenter cross-sectional study. 536 prevalent chronic hemodialysis patients were included. CRP levels, neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) were collected. Kt was obtained by ionic dialysance and urea distribution volume was calculated from the Watson's formula. The sample was divided into two groups, taking the median CRP as the cut-off point. Dialysis adequacy obtained in each group was compared. Finally, a logistic regression model was carried out to determine the variables with the greatest influence. RESULTS: Median CRP was 4.10 mg/L (q25-q75: 1.67-10) and mean Kt/V was 1.48 ± 0.308. Kt/V was lower in the patients included in the high inflammation group (p = 0.01). In the multivariate logistic regression, the "high" levels of CRP were directly correlated with the Log INL (p < 0.001) and inversely proportional with serum albumin values (p = 0.014), Kt/V (p = 0.037) and serum iron (p < 0.001). CONCLUSION: The poorer adequacy in terms of dialysis doses, lower Kt / V values, may contribute to a higher degree of inflammation in chronic hemodialysis patients.

Inflamación y adecuación de la hemodiálisis: ¿están los niveles de proteína C reactiva influidos por la dosis de diálisis recibida? / Inflammation and hemodialysis adequacy: Are C-reactive protein levels influenced by dialysis dose?

Introducción : La inflamación crónica y la subyacente comorbilidad cardiovascular aún son problemas vigentes en los pacientes en hemodiálisis crónica. Existen pocos estudios que comparen la «dosis de diálisis» (Kt/V) con el grado de inflamación del paciente. Nuestro objetivo principal fue determinar si existe una relación entre los niveles séricos de proteína C reactiva (PCR) y el Kt/V utilizando la dialisancia iónica.Métodos : Estudio transversal multicéntrico. Se incluyeron 536 pacientes prevalentes en hemodiálisis crónica. Se recogieron los niveles de PCR, el índice neutrófilo-linfocito y el índice plaqueta-linfocito. Se obtuvo el Kt por dialisancia iónica y el volumen de distribución de la urea mediante la fórmula de Watson. Se dividió la muestra en 2 grupos tomando como punto de corte la mediana de PCR y se comparó la adecuación de diálisis en cada uno. Finalmente, se realizó un modelo de regresión logística para determinar las variables de mayor influencia.Resultados : La mediana de PCR fue 4,10mg/L (q25-q75: 1,67-10). El Kt/V medio fue de 1,48±0,308. El Kt/V fue menor en los pacientes incluidos en el grupo de inflamación alta (p=0,01). En la regresión logística multivariante, los niveles «altos» de PCR tuvieron una correlación directa con el Log índice neutrófilo-linfocito (p<0,001) e inversamente proporcional con los valores de albúmina sérica (p=0,014), Kt/V (p=0,037) y hierro sérico (p<0,001).Conclusión : La peor adecuación en términos de dosis de diálisis (valores de Kt/V más bajos) puede contribuir a un mayor grado de inflamación en los pacientes en hemodiálisis crónica. (AU)

Introduction : Chronic inflammation and the underlying cardiovascular comorbidity are still current problems in chronic hemodialysis patients. There are few studies comparing the “dialysis dose” (Kt/V) with the degree of inflammation in the patient. Our main objective was to determine whether there is a relationship between serum C-reactive protein (CRP) levels and the Kt/V using ionic dialysance.Methods : Multicenter cross-sectional study. A total of 536 prevalent chronic hemodialysis patients were included. CRP levels, neutrophil-lymphocyte ratio and platelet-lymphocyte ratio were collected. Kt was obtained by ionic dialysance and urea distribution volume was calculated from the Watson's formula. The sample was divided into 2 groups, taking the median CRP as the cut-off point. Dialysis adequacy obtained in each group was compared. Finally, a logistic regression model was carried out to determine the variables with the greatest influence.Results : Median CRP was 4.10mg/L (q25-q75: 1.67-10) and mean Kt/V was 1.48±0.308. Kt/V was lower in the patients included in the high inflammation group (P=.01). In the multivariate logistic regression, the “high” levels of CRP were directly correlated with the Log neutrophil-lymphocyte ratio (P<.001) and inversely proportional with serum albumin values (P=.014), Kt/V (P=.037) and serum iron (P<.001).Conclusion : The poorer adequacy in terms of dialysis doses (lower Kt/V values) may contribute to a higher degree of inflammation in chronic hemodialysis patients. (AU)

Inflammation and hemodialysis adequacy: Are C-reactive protein levels influenced by dialysis dose? / Inflamación y adecuación de la hemodiálisis: ¿están los niveles de proteína C reactiva influidos por la dosis de diálisis recibida?

INTRODUCTION: Chronic inflammation and the underlying cardiovascular comorbidity are still current problems in chronic hemodialysis patients. There are few studies comparing the "dialysis dose" (Kt/V) with the degree of inflammation in the patient. Our main objective was to determine whether there is a relationship between serum C-reactive protein (CRP) levels and the Kt/V using ionic dialysance. METHODS: Multicenter cross-sectional study. A total of 536 prevalent chronic hemodialysis patients were included. CRP levels, neutrophil-lymphocyte ratio and platelet-lymphocyte ratio were collected. Kt was obtained by ionic dialysance and urea distribution volume was calculated from the Watson's formula. The sample was divided into 2 groups, taking the median CRP as the cut-off point. Dialysis adequacy obtained in each group was compared. Finally, a logistic regression model was carried out to determine the variables with the greatest influence. RESULTS: Median CRP was 4.10mg/L (q25-q75: 1.67-10) and mean Kt/V was 1.48±0.308. Kt/V was lower in the patients included in the high inflammation group (P=.01). In the multivariate logistic regression, the "high" levels of CRP were directly correlated with the Log neutrophil-lymphocyte ratio (P<.001) and inversely proportional with serum albumin values (P=.014), Kt/V (P=.037) and serum iron (P<.001). CONCLUSION: The poorer adequacy in terms of dialysis doses (lower Kt/V values) may contribute to a higher degree of inflammation in chronic hemodialysis patients.

Dosis de hemodiálisis sub-óptima: Factores predisponentes, causas y prevención / Inadequate doses of hemodialysis. Predisposing factors, causes and prevention

Los pacientes que reciben dosis sub-óptima de hemodiálisis tienen mayor morbimortalidad. El objetivo del trabajo fue identificar los factores predisponentes y las principales causas de diálisis inadecuada y diseñar un algoritmo para aplicar en estos casos. Se realizó un estudio de corte transversal. Se incluyeron 90 pacientes en hemodiálisis crónica, en el Hospital Privado Universitario de Córdoba, en septiembre 2015. Veintidós recibieron una dosis sub-óptima de hemodiálisis. Aquellos con un volumen de distribución de urea (V) mayor a 40 l (72 kg de peso corporal aproximadamente), tienen 11 veces mayores posibilidades (OR = 11.6; IC95% = 3.2-51.7, p < 0.0001) de recibir una dosis inadecuada de hemodiálisis que los que tienen un V menor a esa cifra; y los hombres 3 veces más probabilidad que las mujeres (OR = 3.5; IC95% 1.0-15.8; p = 0.0292). El V mayor a 40 l fue el único factor independiente predictor de sub-diálisis en el análisis multivariado (OR = 10.3; IC95% 2.8-37; p = 0.0004). La principal causa de diálisis sub-óptima fue recibir un flujo sanguíneo (Qb) menor al prescripto (336.4 ± 45.8 vs. 402.3 ± 28.8 ml/min, respectivamente, p < 0.0001) (n = 18). Otras causas fueron: menor duración de la sesión (n = 2), recirculación del acceso vascular (n = 1) y error en las muestras (n = 1). En conclusión, el único factor independiente predisponente de sub-diálisis fue el V mayor a 40 l. La principal causa de diálisis inadecuada fue recibir un Qb menor al prescripto. A partir de estos hallazgos, se desarrolla un algoritmo para aplicar en estos casos.

Patients receiving sub-optimal dose of hemodialysis have increased morbidity and mortality. The objectives of this study were to identify predisposing factors and causes of inadequate dialysis, and to design a practical algorithm for the management of these patients. A cross-sectional study was conducted. Ninety patients in chronic hemodialysis at Hospital Privado Universitario de Córdoba were included, during September 2015. Twenty two received sub-optimal dose of hemodialysis. Those with urea distribution volume (V) greater than 40 l (72 kg body weight approximately) are 11 times more likely (OR = 11.6; CI 95% = 3.2 to 51.7, p < 0.0001) to receive an inadequate dose of hemodialysis, than those with a smaller V. This situation is more frequent in men (OR = 3.5; 95% CI 1.01-15.8; p = 0.0292). V greater than 40 l was the only independent predictor of sub-dialysis in the multivariate analysis (OR = 10.3; 95% CI 2.8-37; p < 0.0004). The main cause of suboptimal dialysis was receiving a lower blood flow (Qb) than the prescribed (336.4 ± 45.8 ml/min vs. 402.3 ± 28.8 ml/min respectively, p < 0.0001) (n = 18). Other causes were identified: shorter duration of the session (n = 2), vascular access recirculation (n = 1), and error in the samples (n = 1). In conclusion, the only independent predisposing factor found in this study for sub-optimal dialysis is V greater than 40 l. The main cause was receiving a slower Qb than prescribed. From these findings, an algorithm for the management of these patients was developed.