Renal Replacement Therapy: Purifying Efficiency of Automated Peritoneal Dialysis in Diabetic versus Non-Diabetic Patients.

BACKGROUND: In order to reduce the cardiovascular risk, morbidity and mortality of peritoneal dialysis (PD), a minimal level of small-solute clearances as well as a sodium and water balance are needed. The peritoneal dialysis solutions used in combination have reduced the complications and allow for a long-time function of the peritoneal membrane, and the preservation of residual renal function (RRF) in patients on peritoneal dialysis (PD) is crucial for the maintenance of life quality and long-term survival. This retrospective cohort study reviews our experience in automatic peritoneal dialysis (APD) patients, with end-stage renal disease (ESRD) secondary to diabetic nephropathy (DN) in comparison to non-diabetic nephropathy (NDN), using different PD solutions in combination. DESIGN: Fifty-two patients, 29 diabetic and 23 non-diabetic, were included. The follow-up period was 24 months, thus serving as their own control. RESULTS: The fraction of renal urea clearance (Kt) relative to distribution volume (V) (or total body water) (Kt/V), or creatinine clearance relative to the total Kt/V or creatinine clearance (CrCl) decreases according to loss of RRF. The loss of the slope of RRF is more pronounced in DN than in NDN patients, especially at baseline time interval to 12 months (loss of 0.29 mL/month vs. 0.13 mL/month, respectively), and is attenuated in the range from 12 to 24 months (loss of 0.13 mL/month vs. 0.09 mL/month, respectively). Diabetic patients also experienced a greater decrease in urine output compared to non-diabetic, starting from a higher baseline urine output. The net water balance was adequate in both groups during the follow up period. Regarding the balance sodium, no inter-group differences in sodium excretion over follow up period was observed. In addition, the removal of sodium in the urine output decreases with loss of renal function. The average concentration of glucose increase in the cycler in both groups (DN: baseline 1.44 ± 0.22, 12 months 1.63 ± 0.39, 24 months 1.73 ± 0.47; NDN: baseline 1.59 ± 0.40, 12 months 1.76 ± 0.47, 24 months 1.80 ± 0.46), in order to maintain the net water balance. The daytime dwell contribution, the fraction of day and the renal fraction of studies parameters provide sustained benefit in the follow-up time, above 30%. CONCLUSIONS: The wet day and residual renal function are determinants in the achievement of the objective dose of dialysis, as well as in the water and sodium balance. The cause of chronic kidney disease (CKD) does not seem to influence the cleansing effectiveness of the technique.

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.

Vascular accesses in haemodialysis: a challenge to be met.

BACKGROUND: Chronic kidney disease is a leading problem in public health due to its high incidence, prevalence and high morbidity and mortality, especially for those who require renal replacement therapy (RRT). As has already been described by other authors, the vascular access is one of the factors determining morbidity and mortality of patients in haemodialysis as well as their complications, which incur a high cost. OBJECTIVES: To know the real situation of our clinical practice, compare it with data from other studies, and to measure the degree of compliance by these patients with the recommendations of haemodialysis (HD) Clinical Practice Guidelines regarding vascular access . Also, to assess survival according to the type of vascular access used, adjusting for comorbidity factors. PATIENTS AND METHODS: We studied the vascular access of our prevalent patients on haemodialysis by October 2009 (n=299, 62% men). Of these, 64% underwent HD through an autologous arteriovenous fistula (AVF), 3% were carrying synthetic grafts, and 33% had a central venous catheter (CVC). These percentages do not comply with the recommendations of the S.E.N. and KDOQI clinical guidelines. In order to know the real situation of our clinical practice, we compared our data with other studies, and measured the degree of compliance with the recommendations of the guidelines. The incident patients on HD were studied from January 2004 to October 2009 (n=422). We analysed basal nephropathy, associated diseases, and the type of vascular access at the start of HD. RESULTS: A total of 30% had an AVF, 1% had synthetic grafts, and 69% had CVC. The calculated relative risk (RR) of death associated with the use of CVC at the start of HD was 3.68 (95% CI: 2.93-6.35) adjusted for other factors of comorbidity (age, diabetes mellitus, ischaemic heart disease, peripheral arterial disease). CONCLUSIONS: The high mortality associated at the beginning of HD with CVC (RR: 3.68), independently of other factors, make the decrease in the use of this vascular access an objective of first order. Presently, we have not been able to meet the objectives from the different Clinical Guidelines with respect to the prevalence and incidence of the vascular accesses for HD.