A comparison of medium-term survival between peritoneal dialysis and haemodialysis in accordance with the initial vascular access.

INTRODUCTION: A study published in 2011 showed that patients in the Canary Islands, who were incident in peritoneal dialysis (PD) had better survival than those who were incident in hemodialysis (HD). Since initiating hemodialysis with central venous catheter is associated with worse prognosis, it would be possible that the initial vascular access influences the results of survival comparison between both groups. OBJECTIVE: To conduct a comparative medium-term survival study of patients incident in renal replacement therapy with different modalities in our community, classifying those incident in hemodialysis according to the initial vascular access: established arteriovenous vascular access or central venous catheter. MATERIAL AND METHOD: Retrospective longitudinal cohort study including all patients who were incident in renal replacement therapy between January 2005 and December 2010, with follow-up until December 2011, in three large hospitals of the Canary Islands. Patients were classified according to the initial modality: PD, HD with established vascular access (HD-FAV) or HD with central venous catheter (HD-Cat). Kaplan-Meier survival curves were estimated for each group and a Cox proportional hazards survival model was used to estimate relative mortality risk for DP as compared to HD-FAV and HD-Cat, adjusting for age and Charlson comorbidity index. An equivalent analysis was then conducted on subgroups defined by age or by the presence of diabetes. RESULTS: 1110 patients were included, with a median age of 63 years, 56% of them were diabetic. A Kaplan-Meier analysis showed better survival for PD (66 months) as compared to HD-Cat (41 months), Log Rank p<.001, with no difference between DP and HD-FAV (67 months). Cox regression RR of mortality for HD-Cat versus PD was 2.270 (1.573-3.276); p<.001; no differences were found between HD-FAV and PD patients 0.993 (0.646-1.525) n.s. Subgroup analysis showed equivalent results for diabetic and non-diabetic patients as well as for younger or older ones. CONCLUSIONS: better survival of PD patients as compared to HD ones, observed in the Canary Islands, seems to be based on incident HD patients with central venous catheter, while no differences were found between PD and HD with established vascular access. These results could suggest that patients in our community, for whom a vascular access cannot be achieved in predialysis, could have better survival if PD is offered as initial technique, at least until a vascular access is available.

Supervivencia comparada a medio plazo entre diálisis peritoneal y hemodiálisis según el acceso vascular de inicio / A comparison of medium-term survival between peritoneal dialysis and haemodialysis in accordance with the initial vascular access

INTRODUCCIÓN: En un estudio publicado en 2011 se observó que en la Comunidad Canaria la supervivencia de los pacientes incidentes en diálisis peritoneal (DP) es mejor que la de los pacientes incidentes en hemodiálisis (HD). El inicio de HD con catéter venoso central condiciona un peor pronóstico, por lo que el acceso vascular de inicio podría condicionar la comparación de la supervivencia entre ambas modalidades. OBJETIVO: Realizar un estudio comparativo en nuestra comunidad de la supervivencia a medio plazo de los pacientes incidentes en tratamiento renal sustitutivo según la modalidad, separando a los pacientes incidentes en HD según el acceso vascular de inicio: acceso vascular arteriovenoso desarrollado o catéter venoso central. MATERIAL Y MÉTODOS: Se trata de un estudio de cohortes longitudinal retrospectivo, que incluyó todos los pacientes incidentes en tratamiento renal sustitutivo entre enero de 2005 y diciembre de 2010 seguidos hasta diciembre de 2011 en tres de los grandes hospitales de la Comunidad Canaria y se dividieron, según la modalidad de inicio, en DP, HD con acceso vascular desarrollado (HD-FAV) y HD con catéter venoso central (HD-Cat). Se estimaron las curvas de supervivencia en los distintos grupos mediante Kaplan-Meier y se aplicó un modelo de riesgos proporcionales de Cox de supervivencia para estimar los riesgos relativos de mortalidad de DP, frente a HD-FAV y HD-Cat, ajustando para edad e índice de comorbilidad de Charlson. Posteriormente se realizó el mismo análisis por subgrupos definidos por la edad y presencia de diabetes. RESULTADOS: Se incluyeron 1110 pacientes, mediana de edad 63 años, 56 % diabéticos. El análisis de Kaplan-Meier muestra una mejor supervivencia de DP (66 meses) frente a HD-Cat (41 meses), log-rank p < 0,001, no existiendo diferencia entre DP y HD-FAV (67 meses). En la regresión de Cox el riesgo relativo de mortalidad de la HD-Cat frente a la DP fue de 2,270 (1,573-3,276); p < 0,001. No se observó diferencia entre los pacientes HD-FAV y DP 0,993 (0,646-1,525). El análisis por subgrupos muestra estos mismos resultados en diabéticos y no diabéticos, y en los pacientes más jóvenes y en los más añosos. CONCLUSIONES: La mejor supervivencia en DP frente a HD observada en el registro de enfermos renales de la Comunidad Canaria parece a expensas de los pacientes incidentes en HD-Cat, no observándose diferencia entre DP y HD-FAV. Estos resultados podrían sugerir que, en nuestro medio, aquellos pacientes en los que, optando inicialmente por HD, no se consigue un acceso vascular desarrollado en la etapa prediálisis podrían obtener un beneficio de supervivencia ofreciéndoles la DP como técnica de inicio, al menos hasta disponer de un acceso vascular definitivo

OBJECTIVE: To conduct a comparative medium-term survival study of patients incident in renal replacement therapy with different modalities in our community, classifying those incident in hemodialysis according to the initial vascular access: established arteriovenous vascular access or central venous catheter. MATERIAL AND METHOD: Retrospective longitudinal cohort study including all patients who were incident in renal replacement therapy between January 2005 and December 2010, with follow-up until December 2011, in three large hospitals of the Canary Islands. Patients were classified according to the initial modality: PD, HD with established vascular access (HD-FAV) or HD with central venous catheter (HD-Cat). Kaplan-Meier survival curves were estimated for each group and a Cox proportional hazards survival model was used to estimate relative mortality risk for DP as compared to HD-FAV and HD-Cat, adjusting for age and Charlson comorbidity index. An equivalent analysis was then conducted on subgroups defined by age or by the presence of diabetes. RESULTS: 1110 patients were included, with a median age of 63 years, 56% of them were diabetic. A Kaplan-Meier analysis showed better survival for PD (66 months) as compared to HD-Cat (41 months), Log Rank p<.001, with no difference between DP and HD-FAV (67 months). Cox regression RR of mortality for HD-Cat versus PD was 2.270 (1.573-3.276); p<.001; no differences were found between HD-FAV and PD patients 0.993 (0.646-1.525) n.s. Subgroup analysis showed equivalent results for diabetic and non-diabetic patients as well as for younger or older ones. CONCLUSIONS: better survival of PD patients as compared to HD ones, observed in the Canary Islands, seems to be based on incident HD patients with central venous catheter, while no differences were found between PD and HD with established vascular access. These results could suggest that patients in our community, for whom a vascular access cannot be achieved in predialysis, could have better survival if PD is offered as initial technique, at least until a vascular access is available