This study will evaluate the cost-effectiveness of unplanned dialysis (peritoneal dialysis and hemodialysis) in chronic kidney disease (CKD) during the first year of therapy in a single center.

Despite evidence of worse outcomes, initiation of renal replacement therapy by unplanned modalities in chronic kidney disease (CKD) patients is the reality in the practice for both hemodialysis and peritoneal dialysis. Unplanned therapy peritoneal dialysis (PD) is the initiation of the modality in less than 48 hours after implantation of the peritoneal catheter, without family training or adequacy of the home. Unplanned hemodialysis (HD) is the initiation of the method without a functional arteriovenous fistula, i.e., with a central venous catheter (nontunneled or tunneled).

Growing evidence shows unplanned PD (or urgent start PD) as a viable and safe alternative to unplanned HD, with the similar rates of infection and survival.

On planned scenario, solid studies demonstrate that PD has a better cost-effectiveness when compared to HD, however the literature lacks in this kind of analysis in unplanned methods.

Briefly, the workgroup will follow patients that would anyway start a Renal Replacement Therapy by an unplanned method and register Government payment for the therapy, including the therapy direct costs and the costs with events (internation, infection), access for dialysis, laboratory and CKD specific medications to performed a cost-effectiveness analysis in both groups (Unplanned Hemodialysis and Unplanned Peritoneal Dialysis).

The workgroup is responsible for the placement of the catheters (PD and HD) using the Seldinger Technique.

The study is unicentric, the therapy is continuous and necessary for the maintenance of life; therefore, no great difficult in the follow up is expected. A database with up-to-date information of patients will be functional during the study.

A Markov model will be developed to assess the relative cost-effectiveness of different dialysis modality distribution scenarios versus current practice. The model considers a hypothetical adult incident patient cohort with end-stage renal disease (ESRD) requiring dialysis and adopts payer perspective. Markov models have been used to model dialysis treatment in previous economic analyses and are widely accepted to be suitable for modelling chronic condition

Statistical analysis plan:

From the study protocol, the data will be entered in a spreadsheet and verified typographical errors and their analysis will be performed using the statistical program Statistical Analysis System (SAS) for Windows (version 9.2: SAS Institute, Cary, North Carolina, USA, 2012).

Considering an alpha error of 0.05 and a beta error of 0.2, power of statistic test of 0.8 and cost difference detection between groups of 15%, the calculated sample size for each group is 94 patients.

Initially descriptive analysis will be done for all patients treated in the period, calculated measures of central tendency and dispersion for continuous variables and frequencies for categorical variables.

For the analysis of repeated measures, asymmetric distribution (gamma) under the Generalized Linear Model (GENMOD) procedure will be used.

Chi Square will be used to compare categorical variable between the two groups. T test or Mann-Whitney will be used to compare parametric continue variables.

By the utilization of Kaplan Meyer and log rank, survival curves of the two groups will be presented at the end of the study. A p-value of 5% or lower will be considered to be statistically significant

Inclusion Criteria:

• Ambulatorial Chronic Kidney Disease patients stage 5 (eGFR < 15 ml/min) or stages 4 with abrupt worsening requiring dialysis treatment immediately followed or not by nephrologists prior to Renal Replacement Therapy indication.

Exclusion Criteria:

• Transitions between HD and PD
• Patients with functional arteriovenous fistula entering hemodialysis
• Patients with functional PD access implanted ate least 48h before the first use
• Patient or family trained in PD and/or with the right adequacy of the home

Incident dialysis patients.