title: Compared decline of residual kidney function in patients treated with automated peritoneal dialysis and continuous ambulatory peritoneal dialysis: a multicenter study.
abstract: BACKGROUND
  There is controversy concerning the compared rates of decline of residual kidney function (RKF) in patients treated with continuous ambulatory peritoneal dialysis (CAPD) and automated peritoneal dialysis (APD).
  
  
  OBJECTIVE
  Following an observational, multicenter design, we studied 493 patients initiating peritoneal dialysis (PD) in four different Spanish units. We explored the effect of the PD modality on the rate of decline of RKF and the probability of anuria during follow-up. We applied logistic regression for intention-to-treat analyses, and linear mixed models to explore time-dependent variables, excluding those affected by indication bias.
  
  
  RESULTS
  Patients started on APD were younger and less comorbid than those initiated on CAPD. Baseline RKF was similar in both groups (p = 0.50). Eighty-seven patients changed their PD modality during follow-up. The following variables predicted a faster decline of RKF: higher (rate of decline) or lower (anuria) baseline RKF, younger age, proteinuria, nonprimary PD, use of PD solutions rich in glucose degradation products, higher blood pressure, and suffering peritonitis or cardiovascular events during follow-up. Overall, APD was not associated with a fast decline of RKF, but stratified analysis disclosed that patients with lower baseline RKF had an increased risk for this outcome when treated with this technique (HR: 2.26, 95% CI: 1.09-4.82, p = 0.023). Moreover, the probability of anuria during follow-up was overtly higher in APD patients (HR: 3.22, 95% CI: 1.25-6.69, p = 0.002).
  
  
  CONCLUSIONS
  Starting PD patients directly on APD is associated with a faster decline of RKF and a higher risk of developing anuria than doing so on CAPD. This detrimental effect is more marked in patients initiating PD with lower levels of RKF.
authors.affiliation: Division of Nephrology, University Hospital A Coruña, A Coruña, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Pérez Fontán
authors.forename: César
authors.initials: C
authors.lastname: Remón Rodríguez
authors.forename: Mercè
authors.initials: M
authors.lastname: Borràs Sans
authors.forename: Emilio
authors.initials: E
authors.lastname: Sánchez Álvarez
authors.forename: Marta
authors.initials: M
authors.lastname: da Cunha Naveira
authors.forename: Pedro
authors.initials: P
authors.lastname: Quirós Ganga
authors.forename: Beatriz
authors.initials: B
authors.lastname: López-Calviño
authors.forename: Carmen
authors.initials: C
authors.lastname: Rodríguez Suárez
authors.forename: Ana
authors.initials: A
authors.lastname: Rodriguez-Carmona
mesh_terms: D005260:Female; D006801:Humans; D007674:Kidney Diseases / Q000503:physiopathology* / Q000628:therapy*; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D010530:Peritoneal Dialysis / Q000379:methods*; D010531:Peritoneal Dialysis, Continuous Ambulatory; D013030:Spain; D016896:Treatment Outcome