Why are we Not Getting More Patients onto Peritoneal Dialysis? Observations From the United States with Global Implications.

Peritoneal dialysis (PD) offers lifestyle advantages over in-center hemodialysis (HD) and is less costly. However, in the United States, less than 12% of end-stage kidney disease (ESKD) patients are maintained on this modality. In this brief review, we discuss some of the factors underlying the low prevalence of PD. These include inadequate patient education, a shortage of sufficiently well-trained medical and nursing personnel, absence of infrastructure to support urgent start PD, and lack of support for assisted PD, among other factors. Understanding and addressing these various issues may help increase the prevalence of PD in the United States and globally.

Burden of Kidney Disease, Health-Related Quality of Life, and Employment Among Patients Receiving Peritoneal Dialysis and In-Center Hemodialysis: Findings From the DOPPS Program.

RATIONALE & OBJECTIVE: Individuals faced with decisions regarding kidney replacement therapy options need information on how dialysis treatments might affect daily activities and quality of life, and what factors might influence the evolution over time of the impact of dialysis on daily activities and quality of life. STUDY DESIGN: Observational cohort study. SETTING & PARTICIPANTS: 7,771 hemodialysis (HD) and peritoneal dialysis (PD) participants from 6 countries participating in the Peritoneal and Dialysis Outcomes and Practice Patterns Studies (PDOPPS/DOPPS). PREDICTORS: Patient-reported functional status (based on daily living activities), country, demographic and clinical characteristics, and comorbidities. OUTCOME: Employment status and patient-reported outcomes (PROs) including Kidney Disease Quality of Life (KDQOL) instrument physical and mental component summary scores (PCS, MCS), kidney disease burden score, and depression symptoms (Center for Epidemiologic Studies Depression Scale [CES-D] score > 10). ANALYTICAL APPROACH: Linear regression (PCS, MCS, kidney disease burden score), logistic regression (depression symptoms), adjusted for predictors plus 12 additional comorbidities. RESULTS: In both dialysis modalities, patients in Japan had the highest PCS and employment (55% for HD and 68% for PD), whereas those in the United States had the highest MCS score, lowest kidney disease burden, and lowest employment (20% in HD and 42% in PD). After covariate adjustment, the association of age, sex, dialysis vintage, diabetes, and functional status with PROs was similar in both modalities, with women having lower PCS and kidney disease burden scores. Lower functional status (score <11) was strongly associated with lower PCS and MCS scores, a much greater burden of kidney disease, and greater likelihood of depression symptoms (CES-D, >10). The median change in KDQOL-based PROs was negligible over 1 year in participants who completed at least 2 annual questionnaires. LIMITATIONS: Selection bias due to incomplete survey responses. Generalizability was limited to the dialysis populations of the included countries. CONCLUSIONS: Variation exists in quality of life, burden of kidney disease, and depression across countries but did not appreciably change over time. Functional status remained one of the strongest predictors of all PROs. Routine assessment of functional status may provide valuable insights for patients and providers in anticipating outcomes and support needs for patients receiving either PD or HD.

Peritoneal or hemodialysis for the frail elderly patient, the choice of 2 evils?

Management of older people on dialysis requires focus on the wider aspects of aging as well as dialysis. Almost all frail and older patients receiving dialysis will default to in-center hemodialysis, although the availability of assisted peritoneal dialysis enables dialysis at home. As with any disease management decision, patients approaching end-stage renal disease need all the appropriate facts about their prognosis, the natural history of their disease without dialysis, and the resulting outcomes and complications of the different dialysis modalities. Hemodialysis in the older age group can be complicated by intradialytic hypotension, prolonged time to recovery, and vascular access-related problems. Peritoneal dialysis can be difficult for older patients with impaired physical or cognitive function and can become a considerable burden. Use of incremental dialysis, changes in hemodialysis frequency, and delivery and use of assistance for peritoneal dialysis can ameliorate quality of life for older patients. Understanding each individual's goals of care in the context of his or her life experience is particularly important in the elderly, when overall life expectancy is relatively short, and life experience or quality of life may be the priority. Indeed, some patients select the option of no dialysis or conservative care. With multifaceted assessments of care, physicians should be able to give individual patients the ability to select and continue to make the best decisions for their care.

First-year outcomes of incident peritoneal dialysis patients in the United States.

BACKGROUND: Patterns of early outcomes in peritoneal dialysis (PD) are not well studied and dialysis providers need to establish a baseline of key outcomes for continuous quality improvement initiatives. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: Incident PD patients from Fresenius Medical Care, North America from January 1 through December 31, 2009. FACTORS: Case-mix, comorbid illness, and baseline laboratory values. OUTCOMES: Death, hospitalization, peritonitis, and switch to hemodialysis (HD) within the first year on PD therapy. MEASUREMENTS: Event rates and outcome predictors. RESULTS: Of 1,677 incident PD patients, 1,313 started on PD therapy and 367 switched from HD therapy within the first 90 days. Normalized first-year event rates for mortality, switch to HD therapy, peritonitis, and hospitalization were 10, 27, 42, and 128 per 100 patient-years, respectively. 336 of 463 (72.6%) first peritonitis episodes and 637 of 939 (67.8%) first hospitalizations occurred within the first 6 months of PD treatment. Black race, higher body mass index, non-Hispanic ethnicity, peripheral vascular disease, and low weekly Kt/V associated with peritonitis risk. Dialysis vintage, female sex, diabetes, congestive heart failure, peripheral vascular disease, and history of limb amputation along with lower laboratory values for albumin, hemoglobin, and phosphorus and weekly Kt/V associated with hospitalization. Switchers to HD therapy (n=350) used central venous catheters 81.4% of the time as initial access (still 78.3% at 90 days later) because of lack of permanent access. LIMITATIONS: Residual confounding from unmeasured variables and exclusion of patients with a training day but who never started home PD therapy. CONCLUSIONS: Despite low first-year mortality, incident PD patients had high morbidity, particularly within the first 3-6 months. Increased focus to identify patients at greatest risk for peritonitis and hospitalization, as well as evaluation of care processes and implementation of preventive strategies, is required. Access planning for transition to HD therapy needs more attention, even during the first PD year.

Prospective safety study of bardoxolone methyl in patients with type 2 diabetes mellitus, end-stage renal disease and peritoneal dialysis.

Patients on peritoneal dialysis experience inflammation associated with advanced chronic kidney disease and the therapy itself. An important consequence of the inflammation may be acceleration of the rate of decline in residual renal function. The decline in residual renal function has been associated with an increased mortality for patients in this population. Bardoxolone methyl is a synthetic triterpenoid. To date, the effects of bardoxolone methyl on kidney function in humans have been studied in patients with type 2 diabetes mellitus. A large-scale event-driven study of bardoxolone methyl in patients with type 2 diabetes mellitus with stage 4 chronic kidney disease is underway. The safety of bardoxolone methyl has not been evaluated in patients with more advanced (stage 5) chronic kidney disease or patients on dialysis. This report describes a proposed double blind, prospective evaluation of bardoxolone methyl in patients with type 2 diabetes mellitus receiving peritoneal dialysis. In addition to assessing the safety of bardoxolone methyl in this population, the study will evaluate the effect of bardoxolone methyl on residual renal function over 6 months as compared to placebo.

Patient-specific phosphorus mobilization clearance during nocturnal and short daily hemodialysis.

The kinetics of plasma phosphorus during different hemodialysis (HD) modalities are incompletely understood. We recently demonstrated that a pseudo one-compartment kinetic model including phosphorus mobilization from various body compartments into extracellular fluids can describe intradialytic and postdialytic rebound kinetics of plasma phosphorus during conventional and short 2-hour HD treatments. In this model, individual patient differences in phosphorus kinetics were characterized by a single parameter, the phosphorus mobilization clearance (K(M)). In this report we determined K(M) in patients treated by in-center nocturnal HD (ICNHD) and short daily HD (SDHD) with low dialyzer phosphate clearance. In the ICNHD study, eight patients underwent 8-hour HD treatments where intradialytic and postdialytic plasma samples were collected; K(M) values were determined by nonlinear regression of plasma concentration as a function of time. In the SDHD study, five patients were studied during 28 treatments for approximately 3 hours. Here, K(M) was calculated using only predialytic and postdialytic plasma phosphorus concentrations. Dialyzer phosphate clearances were 134 ± 20 (mean ± SD) and 95 ± 16 mL/min during ICNHD and SDHD, respectively. K(M) values for the respective therapies were 124 ± 83 and 103 ± 33 mL/min, comparable to those determined previously during conventional and short HD treatments of 98 ± 44 mL/min. When results from ICNHD, SDHD, and previous HD modalities were combined, K(M) was directly correlated with postdialytic body weight (r = 0.38, P = 0.025) and inversely correlated with predialytic phosphorus concentration (r = -0.47, P = 0.005). These findings suggest that phosphorus kinetics during various HD modalities can be described by a pseudo one-compartment model.

Association of social support with outcomes in incident dialysis patients.

BACKGROUND AND OBJECTIVES: The association of social support with outcomes in ESRD, overall and by peritoneal dialysis (PD) versus hemodialysis (HD), remains understudied. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: In an incident cohort of 949 dialysis patients from 77 US clinics, we examined functional social support scores (scaled 0 to 100 and categorized by tertile) both overall and in emotional, tangible, affectionate, and social interaction subdomains. Outcomes included 1-year patient satisfaction and quality of life (QOL), dialysis modality switching, and hospitalizations and mortality (through December 2004). Associations were examined using overall and modality-stratified multivariable logistic, Poisson, and Cox proportional hazards models. RESULTS: We found that mean social support scores in this population were higher in PD versus HD patients (overall 80.5 versus 76.1; P < 0.01). After adjustment, highest versus lowest overall support predicted greater 1-year satisfaction and QOL in all patients (odds ratio 2.47 [95% confidence interval (CI) 1.18 to 5.15] and 2.06 [95% CI 1.31 to 3.22] for recommendation of center and higher mental component summary score, respectively). In addition, patients were less likely to be hospitalized (incidence rate ratio 0.86; 95% CI 0.77 to 0.98). Results were similar with subdomain scores. Modality switching and mortality did not differ by social support in these patients, and associations of social support with outcomes did not generally differ by dialysis modality. CONCLUSIONS: Social support is important for both HD and PD patients in terms of greater satisfaction and QOL and fewer hospitalizations. Intervention studies to possibly improve these outcomes are warranted.

Health-related quality of life in CKD Patients: correlates and evolution over time.

BACKGROUND AND OBJECTIVES: Very few large-scale studies have investigated the determinants of health-related quality of life (HRQOL) in chronic kidney disease (CKD) patients not on dialysis or the evolution of HRQOL over time. DESIGN AND SETTING: A prospective evaluation was undertaken of HRQOL in a cohort of 1186 CKD patients cared for in nephrology clinics in North America. Baseline and follow-up HRQOL were evaluated using the validated Kidney Disease Quality Of Life instrument. RESULTS: Baseline measures of HRQOL were reduced in CKD patients in proportion to the severity grade of CKD. Physical functioning score declined progressively with more advanced stages of CKD and so did the score for role-physical. Female gender and the presence of diabetes and a history of cardiovascular co-morbidities were also associated with reduced HRQOL (physical composite score: male: 41.0 +/- 10.2; female: 37.7 +/- 10.8; P < 0.0001; diabetic: 37.3 +/- 10.6; nondiabetic: 41.6 +/- 10.2; P < 0.0001; history of congestive heart failure, yes: 35.4 +/- 9.7; no: 40.3 +/- 10.6; P < 0.0001; history of myocardial infarction, yes: 36.1 +/- 10.0; no: 40.2 +/- 10.6; P < 0.0001). Anemia and beta blocker usage were also associated with lower HRQOL scores. HRQOL measures declined over time in this population. The main correlates of change over time were age, albumin level and co-existent co-morbidities. CONCLUSIONS: These observations highlight the profound impact CKD has on HRQOL and suggest potential areas that can be targeted for therapeutic intervention.

Metabolic lung disease: diffuse metastatic pulmonary calcifications with progression to calciphylaxis in end-stage renal disease.

The goal of the present case report is to enhance recognition of the incidence of tissue calcifications, which are quite common in patients with end-stage renal disease. We focus on pulmonary metastatic calcifications and the potential progression of this condition to tissue necrosis and lung cavitations in the setting of severe electrolyte imbalance. This case highlights the importance of early identification of the causes and potential risk factors leading to visceral calciphylaxis.

Changes in quality of life during hemodialysis and peritoneal dialysis treatment: generic and disease specific measures.

Despite more than 20 yr of use, relative differences in health-related quality of life (HRQOL) between hemodialysis (HD) and peritoneal dialysis (PD) are not clearly known. The objective of this study was to compare self-reported HRQOL and overall health status for HD and PD patients at the initiation of dialysis therapy and 1 yr later. A prospective cohort of incident ESRD patients was enrolled between October 1995 and June 1998 at 81 outpatient dialysis units in 19 states and included 698 HD and 230 PD patients who completed a baseline CHOICE Health Experience Questionnaire. The main outcome measured was change in qualify-of-life scores from start of dialysis to 1 yr on dialysis and overall health status. Of 928 patients who completed the baseline questionnaire, 585 also completed the 12-mo questionnaire; 101 had died, 55 had received a kidney transplant, and 88 had moved to a new dialysis clinic. PD patients were slightly younger, were more likely to be white, were well-educated, were employed, were married, had less comorbidity, and had higher hematocrit. Unadjusted baseline scores showed better HRQOL for PD patients in both generic and ESRD domains (bodily pain, travel, diet restrictions, and dialysis access [P < 0.05]). At 1 yr, SF-36 scores improved, whereas some ESRD domains improved and others deteriorated. HD patients had greater improvements in two SF-36 domains (physical functioning and general health perception) than PD patients, but results were mixed for ESRD domains (PD is better for finances, HD is better for sleep and overall quality of life). HD and PD patients did not differ in change in overall health status. HD and PD are associated with similar HRQOL outcomes at 1 yr. Generic HRQOL in two domains improved more for HD patients. However, for ESRD-specific HRQOL, results were not consistent; some domains were better for PD patients whereas others were better for HD patients. In advising patients about modality choices, trade-offs should be discussed and individual preferences for specific aspects of HRQOL should be elicited.

Breath ethane in dialysis patients and control subjects.

Oxidant stress may play a role in the accelerated pathology of patients on dialysis, especially in the development of cardiovascular disease, which is a frequent condition in end-stage renal disease (ESRD) patients. Measurement of hydrocarbons can be employed to assess oxidant stress since breath hydrocarbons have been directly traced to in vivo breakdown of lipid hydroperoxides. We undertook to measure ethane, a major breath hydrocarbon, in 15 control subjects, 13 patients on peritoneal dialysis (PD), and 35 patients on hemodialysis (HD). Within the HD group, we separately examined 12 diabetic and 23 nondiabetic patients. Breath samples were collected after patients had breathed purified air for 4 min, and ethane content was measured by GC and expressed as pmoles/kg-body weight-minute (pmol/kg-min). As the data for the hemodialysis patients appeared skewed, nonparametric statistical techniques were employed to analyze these data, which are reported as median and interquartile range (IQR). Ethane levels were similar in 15 control subjects (median, 2.50 pmol [1.38-3.30]/kg-min] and 13 PD patients (median, 2.51 pmol [1.57-3.17]/kg-min). Breath ethane was significantly elevated in a portion (18 of 35 patients, 52%) of the HD patients (median, 6.16 pmol [4.46-8.88]/kg-min) (p <.001 vs. control, Mann-Whitney U test). Two of the diabetic HD patients showed extremely high values of breath ethane. Breath ethane was not altered by a single hemodialysis session, suggesting that long-term metabolic processes contribute to its elevation. Measurement of breath ethane may provide insight into severity of oxidant stress and metabolic disturbances, and provide guidance for optimal therapy and prevention of pathology in patients on long-term hemodialysis.