Compared time profiles of ultrafiltration, sodium removal, and renal function in incident CAPD and automated peritoneal dialysis patients.
BACKGROUND
Fluid and sodium removal rates may not be equivalent in patients undergoing automated peritoneal dialysis (APD) and continuous ambulatory peritoneal dialysis (CAPD). This may influence compared cardiovascular outcomes in both groups.


METHODS
The authors compared prospectively the time courses of ultrafiltration, sodium removal, and residual renal function (RRF) in a group of incident patients treated with CAPD (n = 53) or APD (n = 51) for at least 1 year (mean follow-up, 28.9 months; range, 13 to 62). The authors analyzed potential effects of these factors on blood pressure (BP) control and cardiovascular morbidity and mortality.


RESULTS
Ultrafiltration and sodium removal rates were consistently lower in APD patients (mean differences, 236 mL/d; P = 0.012, and 36 mmol/d; P = 0.018, respectively, end of first year). Moreover, univariate and multivariate analysis indicated that APD therapy results in a moderate, but significantly faster decline of RRF than CAPD therapy. Analysis of clinical outcomes showed that CAPD (versus APD) therapy or higher ultrafiltration or sodium removal rates were associated with a better time course of systolic, but not diastolic, BP. We were unable to identify PD modality, ultrafiltration, or sodium removal rates as independent predictors of cardiovascular morbidity and mortality.


CONCLUSIONS
Ultrafiltration and sodium removal rates are consistently lower in incident APD patients than in their counterparts undergoing CAPD. Moreover, RRF declines faster during APD than during CAPD therapy, although this difference may be partially counteracted by a detrimental effect of ultrafiltration on RRF. Aside from a better control of systolic BP in CAPD patients, these differences do not portend significant cardiovascular consequences during the first years of PD therapy.
Rodriguez-Carmona
Ana
A
Division of Nephrology, Hospital Juan Canalejo, A Coruña, Spain.
Pérez-Fontán
Miguel
M
Garca-Naveiro
Rafael
R
Villaverde
Pedro
P
Peteiro
Javier
J
D017677:Age Distribution; D000368:Aged; D002318:Cardiovascular Diseases / Q000401:mortality*; D002423:Cause of Death; D015897:Comorbidity; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000453:epidemiology; D007676:Kidney Failure, Chronic / Q000453:epidemiology / Q000503:physiopathology* / Q000628:therapy*; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D010531:Peritoneal Dialysis, Continuous Ambulatory / Q000706:statistics & numerical data*; D011446:Prospective Studies; D017678:Sex Distribution; D012964:Sodium / Q000032:analysis; D013997:Time Factors; D016896:Treatment Outcome; D014462:Ultrafiltration / Q000706:statistics & numerical data*
D012964:Sodium