Prevalent Peritoneal Dialysis Research Articles

Serial prealbumin levels as predictors of outcomes in a retrospective cohort of peritoneal and hemodialysis patients

Objective: Although earlier research has suggested that baseline prealbumin level is an independent predictor of outcome among dialysis patients, the prognostic importance of serial prealbumin levels is less clear. The present study had 3 objectives: first, to determine if prealbumin (a marker of visceral protein stores with a relatively short half-life) predicts subsequent albumin levels taken at least 1 month later; second, to examine the association between serial prealbumin levels and clinical outcome; and third, to examine the association between changes in prealbumin level and outcome. Design: The prognostic value of serial prealbumin levels was examined by linear regression analysis and Cox hazard models in an observational cohort study using a repeated measures design and time-dependent covariates. Setting: Patients were followed by a tertiary care center, receiving hemodialysis (HD; at either an in-center dialysis unit or one of several satellite units operated by the hospital) or home peritoneal dialysis (PD). Patients: A retrospective cohort was identified consisting of 268 incident and prevalent chronic HD and PD patients receiving dialysis from June 1998 to September 1999. Main outcome: The study examined the association between serial prealbumin measurements and future laboratory and clinical outcomes (albumin, hospitalization, and death). Results: Serial prealbumin values were independent predictors of future albumin levels among HD patients (P = .04), but not PD patients. Independent predictors of hospitalization included diabetes for PD patients (P = .0012) and advanced age for HD patients (P = .0008). Advanced age and diabetes were independent predictors of death for both HD (P = .0001 and P = .0368) and PD patients (P = .0014 and P = .0164). Serial prealbumin values, measured as time-dependent covariates, did not predict hospitalization or death. Further analyses examined the prognostic value of changes in prealbumin and albumin values as time-dependent covariates. The final multivariate analysis identified low baseline albumin level as an independent predictor of hospitalization among HD patients (P = .0282), whereas low baseline prealbumin was an independent predictor of death for HD patients (P = .0001). Interestingly, negative changes in serial prealbumin measurements were also independent predictors of death among HD patients (P = .0025). Conclusion: Serial prealbumin measurements predict subsequent albumin values among HD patients. As well, low baseline prealbumin level is an independent predictor of adverse outcome among HD patients. Although repeated prealbumin measurements in and of themselves were of no added prognostic value, falling prealbumin values identified by repeated measurements were additional independent predictors of death. These results support the clinical utility of regular prealbumin monitoring among HD patients. © 2001 by the National Kidney Foundation, Inc.

Chlamydia Pneumoniae DNA in Peripheral Blood Mononuclear Cells in Peritoneal Dialysis Patients

The aim of the present study was to examine the association between infection with Chlamydia pneumoniae and symptomatic atherosclerosis in peritoneal dialysis (PD) patients. Cross-sectional study. Peritoneal Dialysis Unit of Kingston General Hospital. Fifty-five prevalent PD patients. (1) Infection with C. pneumoniae diagnosed by detection of DNA in peripheral blood mononuclear cells (PBMCs) using polymerase chain reaction. (2) Symptomatic atherosclerosis involving the coronary, cerebral, or peripheral circulation. The DNA of C. pneumoniae was detected in PBMCs in 33 patients (60.0%). Atherosclerosis was present in 16 of 33 (48%) PBMC C. pneumoniae DNA-positive patients, and in 10 of 22 (45%) PBMC C. pneumoniae DNA-negative patients (p = 0.83). Using multiple logistic regression and controlling for a number of known cardiovascular risk factors, PBMC C. pneumoniae DNA status was not predictive of atherosclerosis. The only significant independent predictors of atherosclerosis were diabetes and age. In prevalent PD patients, a high prevalence of symptomatic atherosclerosis and of Chlamydia pneumoniae DNA in PBMCs were seen; however, the results of the present study do not support the presence of an association between infection with C. pneumoniae and atherosclerosis.

Is Obesity a Favorable Prognostic Factor in Peritoneal Dialysis Patients?

To determine the influence of an elevated body mass index (BMI) on cardiovascular outcomes and survival in peritoneal dialysis (PD) patients. Prospective, observational study of a prevalent PD cohort at a single center. Tertiary care institutional dialysis center. The study included all patients with a BMI of at least 20 who had been receiving PD for at least 1 month as of 31 January 1996 (n = 43). Patients were classified as overweight [BMI > 27.5; mean +/- standard error of mean (SEM): 32.1 +/- 1.1; n = 14] or normal weight (BMI 20-27.5; mean +/- SEM: 23.8 +/- 0.4; n = 29). Patient survival and adverse cardiovascular events (myocardial infarction, congestive cardiac failure, cerebrovascular accident, and symptomatic peripheral vascular disease) were recorded over a 3-year period. At baseline, no significant differences were seen between the groups in clinical, biochemical, nutritional, or echocardiographic parameters, except for a lower dietary protein intake (0.97 +/- 0.10 g/kg/day vs 1.44 +/- 0.10 g/kg/day, p = 0.004) and a higher proportion of well-nourished patients by subjective global assessment (100% vs 72%, p < 0.05) in the overweight group. After 3 years of follow-up, 29% of overweight patients and 69% of normal-weight patients had died (p < 0.05). Using a Cox proportional hazards model, a BMI greater than 27.5 was shown to be an independent positive predictor of patient survival, with an adjusted hazard ratio (HR) of 0.09 [95% confidence interval (CI): 0.01-0.85; p < 0.05]. However, being overweight did not significantly influence myocardial infarction-free survival (adjusted HR: 0.33; 95% CI: 0.07-1.48; p = 0.15) or combined adverse cardiovascular event-free survival (adjusted HR: 0.67; 95% CI: 0.23-1.93; p = 0.46). Obesity conferred a significant survival advantage in our PD population. Obese patients should therefore not be discouraged from receiving PD purely on the basis of BMI. Moreover, maintaining a higher-than-average BMI to preserve "nutritional reserve" may help to reduce the mortality and morbidity rates associated with PD.

Risk factors for peritonitis in long-term peritoneal dialysis: The Network 9 peritonitis and catheter survival studies

To determine factors involved in peritoneal dialysis-associated peritonitis and catheter loss, all point prevalent peritoneal dialysis patients in Health Care Finance Administration (HCFA) end-stage renal disease (ESRD) Network 9 were followed throughout 1991 for peritonitis events and throughout 1991 to 1992 for catheter survival. Data were collected by questionnaires compiled by the dialysis facility and validated by network staff. Peritonitis was reported 1,168 times in 729 of the 1,930 patients. By gamma-Poisson regression, a significantly increased risk for peritonitis was observed for patients with previous peritonitis, black race, and those dialyzing with standard connectors or cyclers compared with disconnect systems. Decreased risks were observed for patients with longer ESRD experience and when prophylactic antibiotics were administered before catheter insertion. Postinsertion leakage, diabetes, visual problems, previous or current immunosuppression, and physical activity were not risk factors. Infection of any kind caused the removal of 68% of the 414 catheters lost. Patients with downward-directed tunnels were less likely to experience concomitant exit site/tunnel infections associated with peritonitis. Peritonitis episodes with Staphylococcus epidermidis-like organisms were more likely to resolve with a single course of antibiotics. Perhaps because of their higher infection rate, blacks were more likely than whites to use a disconnect system. In general, the outcome of peritonitis in blacks was similar to that in whites, except that blacks were less likely to be hospitalized and were less likely to die.

Differential Glucocorticoid Responsiveness of Dialysis Patients’ Lymphocytes

To evaluate in vitro glucocorticoid responsiveness of phytohemagglutinin (PHA)-stimulated lymphocytes from peritoneal dialysis (PD) patients compared to hemodialysis (HD) patients. Cross-sectional study of prevalent PD and HD patients and concurrent control subjects. Urban outpatient dialysis unit. 20 HD, 14 PD, and 20 control subjects. Using standard lymphocyte culture techniques, the concentration of prednisolone (P) and methylprednisolone (MP) required to cause 50% inhibition (IC50) of the proliferative response to phytohemagglutinin (PHA) was determined from dose-response curves. There was considerable heterogeneity in the sensitivities of individual patients' PBMC to glucocorticoid inhibition, especially those of HD patients' cells to P. The mean +/- SD IC50 for MP was significantly (p < or = 0.001) lower than that for P in each cohort: PD 11 +/- 5 vs. 34 +/- 18 ng/mL; HD 22 +/- 14 vs. 89 +/- 43 ng/mL; control subjects 14 +/- 11 vs. 55 +/- 56 ng/mL. Interestingly, the IC50 for both P and MP was significantly higher in HD than in either PD or controls (ANOVA, P: F = 6.56, p = 0.003; MP: F = 3.77, p = 0.03), indicating decreased sensitivity of HD lymphocytes to both drugs. There were no significant differences in mean IC50 values for either P or MP between PD and controls. No correlations were found between IC50 for either P or MP and patient age, gender, duration of dialysis, serum creatinine, serum albumin, or parathyroid hormone level. In vitro glucocorticoid responsiveness of dialysis patients' lymphocytes appears to be influenced by dialysis modality, but the factor(s) involved remains to be determined. The greater sensitivity of PD lymphocytes to both P and MP might result in better immunosuppression and less severe rejection after renal transplantation. MP may be particularly advantageous following renal transplantation for any patient manifesting relative or absolute in vitro resistance to P.

ABO blood group and secretor status in stomal ulcer.

<h3>Summary</h3> The use of peritoneal dialysis (PD) has become wide spread since the introduction of continuous ambulatory PD more than 25 years ago. Over this time, many advances have been made and PD is an alternative to hemodialysis (HD), with excellent comparable survival, lower cost, and improved quality of life. The percentage of prevalent PD patients in the United States is approximately 7%, which is significantly lower compared with the 15% PD prevalence from the mid-1980s. Despite comparable survival of HD and PD and improved PD technique survival over the last few years, the percentage of patients performing PD in the United States has declined. The increased numbers of in-center HD units, physician comfort with the modality, perceived superiority of HD, and reimbursement incentives have all contributed to the underutilization of PD. In addition to a higher transplantation rate among patients treated with PD in the United States, an important reason for the low PD prevalence is the transfer to HD. There are various reasons for the transfer (<i>e.g.</i>, episodes of peritonitis, membrane failure, patient fatigue, etc.). This review discusses the various factors that contribute to PD underutilization and the rationale and strategies to implement “PD first” and how to maintain it. The PD first concept implies that when feasible, PD should be offered as the first dialysis modality. This concept of PD first and HD second must not be seen as a competition between therapies, but rather that they are complementary, keeping in mind the long-term goals for the patient.