Peritoneal dialysis in the US: Evaluation of outcomes in contemporary cohorts

Transcription

1 & 2006 International Society of Nephrology Peritoneal dialysis in the US: Evaluation of outcomes in contemporary cohorts S Mujais 1 and K Story 1 1 Renal Division, Baxter Healthcare Corporation, McGaw Park, Illinois, USA Secular trends in dialysis therapy delivery require a frequent re-examination of outcomes in patients on renal replacement modalities. We examined four large cohorts of patients initiating peritoneal dialysis (PD) in (total of patients) to ascertain trends in patient outcomes, technique success, and predictors of both parameters of interest. Age, end-stage renal disease vintage, and diabetes were clear predictors of patient survival. Technique success was higher in patients on automated PD than in patients on continuous ambulatory PD. Center size was a powerful predictor of technique success. We conclude that the current state of PD in the United States is characterized by improving patient outcomes, higher technique success, and a predominance of use of cycler-based therapy. Several opportunities for improving technique success amenable to practice interventions have been identified.. doi: /sj.ki KEYWORDS: peritoneal dialysis; patient survival; technique survival Correspondence: S Mujais, Renal Division, Baxter Healthcare Corporation, 1620 Waukegan Rd, MPGR-A2, McGaw Park, Illinois , USA. salim_mujais@baxter.com Dialysis care is a dynamic process subject to the influence of advances in clinical processes and technological innovations. Trackingseculartrendsinthisprocesshelpselucidatesuccesses as well as opportunities for practice modifications or areas in need of iterative technical innovations. Evaluations of these trends can derive from multiple sources. National and regional registries have offered valuable insights into the survival of patients on various dialytic modalities and rates of modality transfers These studies are limited, however, in the area of causations of modality transfer and on the impact of submodality utilization (ambulatory automated peritoneal dialysis (APD) vs continuous ambulatory peritoneal dialysis (CAPD)). Single-center studies have been valuable in the degree of detail they offer, but generalizations from these studies are limited as they represent a distinct locale and practice group and are thus subject to biases of center effect. 8,11 33 Both national and single-center studies can also be limited in their timeliness and the interval between data acquisition and final analysis leading to publication. It is intuitively obvious that data relating to cohorts of patients of several years past may be valuable but not uniformly pertinent to modern practice. Regrettably, such outdated data from national registries and cohort studies 37 have had an impact on views of modality choices, and the prestige of a large registry or a national cohort has often obscured glaring shortcomings. Similarly, single-center studies tend to telescope information over several years (decades sometimes) to obtain a sample size suitable for meaningful analysis. 18,20,21,23,30,33,38 An approach that can bypass the limitations of lack of timeliness and generalization would be valuable in elucidating the trends in dialytic therapy particularly in the context of identifying areas of success that validate certain clinical approaches and areas of opportunities for practice modification. The present analysis was undertaken to provide insight into the status of patient and technique survival in contemporary cohorts of patients on peritoneal dialysis (PD) in the United States (US) and represents both a temporal extension as well as a refined analysis of our previous work on the topic. 39 RESULTS General characteristics of the population The overall profile of the study populations is illustrated in Table 1. The majority of patients starting PD in any of the S21

2 four calendar years were new to dialysis. However, a substantial proportion of patients was transferred from hemodialysis (HD). In all four cohorts, a slight preponderance of males is observed for patients new to dialysis and transferred from HD. The proportion of patients with diabetes was similar to that reported for the general United States Renal Data System (USRDS), but the mean age was younger, consistent with the premise of greater self-care dialysis in younger age groups. Patients transferred from HD had a similar profile as patients new to dialysis in terms of age, gender distribution, diabetes prevalence, and choice of APD vs CAPD. An increasing proportion of patients starting PD in each of the successive calendar years was selecting APD as their submodality of choice, suggesting that cycler-based therapy is becoming the dominant mode of PD in the US. As center size has been identified by us 39 and others 1,2 as critical in affecting outcomes of interest, we looked both at the distribution of centers by size and the proportions of patients in each center category. These results are shown in Figure 1. Of the 1768 centers included in the database, 80% had fewer than 20 patients. These centers accounted for Table 1 General demographics of the study cohorts 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Centers Year Total Male:Female (%) 53:47 52:48 53:47 53:47 DM:Non-DM (%) 44:56 43:57 43:57 44:56 APD:CAPD (%) 58:42 61:39 64:36 64:36 Age (years) New to dialysis DM:Non-DM (%) 45:55 44:56 44:56 45:55 Male:Female (%) 54:46 52:48 53:47 53:47 APD:CAPD (%) 58:42 61:39 64:36 65:35 Age (years) Transfer from HD DM:Non-DM (%) 44:56 43:57 42:58 45:55 Male:Female (%) 53:47 53:47 52:48 53:47 APD:CAPD (%) 56:44 60:40 62:38 64:36 Age (years) APD, automated peritoneal dialysis; CAPD, continuous ambulatory peritoneal dialysis; DM, diabetes mellitus; HD, hemodialysis. Patients <40 20 <30 10 <20 0 <10 Figure 1 Distribution of centers by center size and proportions of PD patients treated in each individual center size category. 43% of patients on PD. Conversely, 57% of patients was cared for in centers with more than 20 patients and 26% of patients was in centers with more than 40 patients on census. Not surprisingly, center activity (number of new PD patients per year) correlated very closely with center size. Fifty-five percent of centers started less than five patients per year on PD, 22% started between five and 10 patients annually, and 23% started more than 10 patients each year. Patient survival The survival of patients at various time intervals is illustrated in Table 2. Values for first-year survival for patients new to dialysis for each of the cohort years were: 85.98% for 2000, 87.08% for 2001, 86.85% for 2002, and 87.14% for Patients new to dialysis had a slightly higher survival than those transferred from HD. Vintage with end-stage renal disease (ESRD) may play a role in this difference. Predictably, age was a clear determinant of patient survival as was diabetic status. Gender did not appear to have a significant effect on survival. On univariate analysis, age (Po0.0001), diabetes (Po0.0001), patient type (Po0.0001), center size (Po0.005), modality (APD vs CAPD) (Po0.0001), and gender (Po0.05), had an effect on survival. However, when using a stepwise Cox regression analysis, only age, diabetes, and type of patient showed a significant effect (Table 3). These observations were true for the pooled data set as well as for individual year cohorts. We observed a progressive increase in adjusted death rate over successive 6-month intervals (i.e., mortality for any 6-month interval was lower than most subsequent 6-month intervals). A similar analysis revealed that the survival advantage of APD over CAPD observed on univariate analysis was restricted to the first 6 months of therapy (relative risk for CAPD death rate to APD death rate 1.44, Table 2 Patient survival in various subsets 1 Year 2 Years 3 Years 4 Years Patient origin New to dialysis Transfer from HD Age (years) Diabetic status DM Non-DM Gender Female Male DM, diabetes mellitus; HD, hemodialysis. S22

3 Table 3 Determinants of patient and technique survival, and transplantation rate Patient survival Hazard ratio P Technique survival Hazard ratio P Transplantation Hazard ratio P Age 1.04 o o o Patient type a o o o Diabetes b o o o Center census 0.94 o o Modality c o Gender o0.001 APD, automated peritoneal dialysis; CAPD, continuous ambulatory peritoneal dialysis; DM, diabetes mellitus; HD, hemodialysis. Age: risk increase for each year older; patient type: risk decrease for new to dialysis vs transfer from HD; diabetes: risk decrease for non-diabetic vs diabetic; center census: risk decrease for each census category higher; modality: risk decrease for APD vs CAPD. a New to dialysis vs transfer from HD. b DM vs non-dm. c APD vs CAPD. Po0.0001). The impact of diabetic status was apparent at all time intervals, with non-diabetic patients having a lower relative risk (between 0.49 and 0.78, Po0.0001). Patients transferring from HD had a higher relative risk (between 1.43 and 1.69, Po0.0001) for all intervals within 36 months with equalization of risk after that time. Cardiovascular causes of death (60%) predominated for the pooled group as well as for individual year cohorts. Technique success Technique survival at various time intervals and for various subsets is shown in Table 4. Patients new to dialysis, nondiabetic patients, patients from larger centers, and patients on APD had better technique survival than their corresponding counterparts (transfer from HD, diabetic, small center, and CAPD, respectively) (Table 3). These effects were true for the pooled data set and for individual year cohorts. The proportional contributions of different causes of transfer to HD are shown in Figure 2. Infectious complications were the most frequent cause followed equally by mechanical catheter problems, inadequate dialysis (including fluid management), and psychosocial reasons. We observed a declining trend for infectious complications, catheter problems, and inadequate dialysis from the 2000 to the 2003 cohorts (2 3% decline in absolute occurrence). We also observed a correlation between parameters in Table 3 influencing overall technique success and the specific causes of transfer to HD. Center characteristics correlated with catheter problems (Po0.0001), inadequate dialysis (Po0.01), and infectious complications (Po0.01); the occurrence of transfer because of these issues was less in the larger centers. Patients on APD had lower rates of transfer across all reasons. The temporal profile for the adjusted rate of transfer to HD was highest in the first 6 months on PD (relative risk , Po vs all successive 6 month periods) Table 4 Technique survival in various subsets 1 Year 2 Years 3 Years 4 Years New to dialysis Transfer from HD Age (years) Diabetic status DM Non-DM Center census X PD modality APD CAPD APD, automated peritoneal dialysis; CAPD, continuous ambulatory peritoneal dialysis; DM, diabetes mellitus; HD, hemodialysis. Other 22% Psycho-social 15% Inadequate dialysis 18% Infection 28% Catheter problems 17% Figure 2 Proportional distribution of causes of transfer from PD to HD. and declined thereafter to a stable rate (i.e., after the first 6 months, the rate was not different between all successive intervals). The phenomenon of early transfer to HD was pronounced in CAPD patients, but was not observed in APD patients (adjusted relative risk CAPD vs APD in the first 6 months 1.72, Po0.0001, but not different thereafter). Similarly, the effect of center characteristics, age, and patient type on adjusted transfer rate were most pronounced in the first year of therapy (Po0.0001) and abated thereafter. Transfer to HD was lower in patients on APD than in patients on CAPD overall and in each category of transfer causes (Po0.0001). This differential was most evident in the first year on PD and tended to disappear during the second year of therapy. Closer examination of the transfer curves suggested that the rate of transfer in CAPD patients was highest during the first 6 months of therapy and tended to stabilize beyond that point. The time period prior to the S23

4 inflection point can thus be viewed as a period of vulnerability to technique failure and may need to become a focus of interventional scrutiny. Transplantation By univariate and stepwise Cox regression analysis, the likelihood of transplantation was affected by age, type of patient, diabetes, center characteristics, PD modality, and gender (Table 3). These findings were true for the pooled data set as well as for each cohort year examined separately. Adjusted transplant rate was lowest in the first 6 months (3.4 transplants per 100 patient years, relative risk , Po vs all successive intervals beyond the first 6 months). The lower adjusted rate for transplant for women was observed for only the first 24 months by interval Poisson regression. DISCUSSION The present study examined the profile of PD practice in the US in four large inception cohorts of patients who started PD in the years These large cohorts have allowed us to gain insight into the practice patterns as well as the patient and technique outcomes in contemporary patient populations. The findings of this study will be discussed under several general headings: the characterization of the population on PD in general, determinants of patient survival, factors influencing technique success, and the rates of transplantation in this population. The demographic characteristics of the patient population in the present study are similar to those of the dialysis population in the US in general and PD patients in particular, 40,41 and can thus be considered as representative of the state of patients on PD. Patients labeled as new to dialysis in the present study correspond to the patients reported in the USRDS as incident patients. It appears, however, that the numbers reported in the USRDS Annual Data Report (ADR 2005) for the years corresponding to our study cohorts under-represent the number of patients starting PD. Indeed, for 3 of the 4 years, the number reported by the USRDS is less than the number of patients in our study. Since only patients using Baxter PD systems are reported in our database, it is likely that the numerical values in the USRDS database represent an undercounting of patients going on PD as their first dialysis modality. This may be explained by the fact that for each year the USRDS reports a number of patients under uncertain dialysis and many of these may have been patients starting PD. Another discrepancy with the USRDS is the proportion of patients on cycler therapy. The proportions of prevalent patients on APD reported in the 2002 USRDS ADR for 2000 was 33.47% and in the 2005 ADR for 2003 was 56% (Table 4 4f; USRDS ADR 2005). These aberrant results in the USRDS ADR are likely due to inaccuracies in reporting of PD modality subtype within that system. In our database, determination of PD submodality is based on the actual presence of a cycler in the patients homes and hence is a definitive ascertainment of submodality assignment. Our cohorts, therefore, have the advantage of better delineation of PD submodality distribution. Part of the discordance may also be due to low utilization of cycler therapy in centers not included in our database. The proportion of diabetic patients in our cohorts corresponds to the values reported for all dialysis patients in the USRDS database: 45.2% in 2000 and 45.9% in 2001 (USRDS ADR 2002, Table C-11), and for PD patients specifically. 40,41 The current PD population in the US is thus characterized by a younger age than the overall ESRD population, a similar prevalence of diabetes mellitus, and a very high utilization of APD. Our analysis also illustrates the large proportion of patients starting PD within any particular year that are transfers from chronic HD. This implies that at any point in time, a large proportion of patients on PD have a history of HD treatment. This highlights the limitations of outcome studies that look at prevalent populations and do not consider the vintage of patients and preceding renal replacement therapy. Even prospective cohort studies have not been immune to the problem of ignoring ESRD vintage in patients assigned to PD. 37 Patient survival in the present study cohorts is not very dissimilar from findings in Europe. The Netherlands Cooperative Study on the Adequacy of Dialysis (NECOSAD) trial observed a 2-year patient survival in incident patients of 77%, 8 a percentage not different from our overall 2-year survival of 75.77% in incident patients new to dialysis. This is seen despite a lower prevalence of diabetes mellitus in the NECOSAD trial (16 20 vs 45% in current study). In a separate study, however, the survival of patients in the NECOSAD trial was reported as 84%. 42 This difference was due to the exclusion of patients in the second study that did not have full baseline data for the analysis, these excluded patients having higher mortality. Our results are also similar to findings of the Danish registry 10 and the latter had only 21% of patients with diabetes. Technique survival, however, in our series was slightly lower than that observed in the NECOSAD trial. 42 In concordance with other studies, age, ESRD vintage, and diabetes mellitus were independent determinants of patient survival. 5,8,43 46 An interesting observation in this study is the impact of PD modality on patient survival. We observed a higher survival rate for patients on APD vs patients on CAPD in the first 6 months of therapy. Several factors can be invoked to explain this observation. It is possible, though difficult to explore in the present database, that the type of patients allocated to APD have certain characteristics that are favorable to survival that are not adjusted for in our outcome analysis. Patients with an active lifestyle may prefer APD for the logistic advantages and these patients may inherently have a better survival that co-segregates with the choice of APD submodality. Alternatively, it is possible that patients on APD have better compliance with therapy and better ultrafiltration with the short cycler dwells and these two S24

5 factors may influence survival. This is clearly an area that warrants additional future research. Secular trends in technique survival have been documented from population-wide registries. 3,39 In the current study, we observed two temporal trends of technique success. There are notable differences in technique success across calendar years. We also observed a decline in technique failure between the first 6 months and subsequent intervals on therapy. One factor that had a dominant effect on technique success was the submodality of PD. Patients on APD had a better technique success compared to patients on CAPD due to a higher rate of technique failure in CAPD during the first 6 months on therapy. The observation that center characteristics have an impact on patient and technique outcome was explored by Schaubel et al. 2 in the Canadian population. They observed that as the cumulative number of PD patients treated increased, covariate-adjusted mortality significantly decreased; a weaker yet significant association was observed between number of PD patients treated and technique failure. As the percentage of patients initiating dialysis on PD increased, technique failure rates decreased significantly. Using data from the comprehensive Dutch End-Stage Renal Disease Registry (RENINE), Huisman et al. 1 analyzed PD technique failure rates in the period Mean annual technique failure rates varied greatly between centers and correlated with the number of patients on PD in the center and with the fraction of patients on PD. Low technique survival rates occurred mainly in centers with less than 20 patients on PD; relative risk for technique failure was 1.68 compared with larger centers. An increased risk of technique failure occurred with fewer than 20 PD patients in a center or when a small proportion of patients were on PD. In the present study, center size was found to have an effect on technique success. Unlike Schaubel et al., 2 we found no effect of center size on patient survival except on univariate analysis and in a time restricted window (first 6 months on PD), but like Huisman et al. 1 and Schaubel et al., 2 center size in our analysis did affect technique success rates. The results of all three studies (Canada, 2 the Netherlands, 1 and present report) imply that a center s experience with and degree of specialization toward PD have a strong impact on PD outcomes. One hypothesis is that a center s propensity to exploit technical and non-technical advances in PD increases directly with experience. It is also possible that, through experience, centers become more adept at identifying appropriate patients to receive PD. An evaluation of the USRDS database suggests that transplant rates are higher in PD patients than HD patients. 47 In a stepwise Cox regression analysis applied to the combined four inception cohorts in this study, older age, diabetes, and female gender were all independently associated with a lower transplantation rate. Studies in both the US 47 and Canada 48 have identified similar patterns. In summary, examination of contemporary cohorts of patients on PD in the US reveals a high level of utilization of automated PD (APD). Trends towards improved patient survival, higher technique success, and increasing use of cycler-based therapy with more recent calendar years were noted. Age, ESRD vintage, and diabetes were clear predictors of patient survival. Technique success was higher in patients on APD than in patients on CAPD. Center size was a powerful determinant of technique success. We conclude that the current state of PD in the US is characterized by improving patient outcomes, higher technique success, and a predominance of use of cyclerbased therapy. Several opportunities amenable to practice interventions for improving technique success have been identified. MATERIALS AND METHODS The present analysis is based on four cohorts of US patients that started PD in the years 2000, 2001, 2002, and 2003, and were followed until June Information about these patients is tracked in the Baxter Healthcare Corporation On-Call TM system, which tracks in a Health Insurance Portability and Accountability Act (HIPAA)-compliant approach standard demographics, treatment history for renal disease (new to dialysis vs transfer from HD), transfer from PD to HD (including causes) or transplant, patient outcome, and general details of dialytic therapy such as submodality use (CAPD vs APD). 39 This information is gathered as a component of the home delivery system of dialysis supplies and hence has the distinct advantage of reflecting actual rather than reported conditions. De-identified information from this system forms the basis of this analysis. A detailed list of possible causes of mortality and of transfer to HD is maintained within the system to allow for categorization of primary causes of mortality and modality transfer. All events within this system are dated; therefore, potential trends of interest can be examined and time windows of event occurrences can be determined. Rate of transfer to HD was defined as the number of patients transferred to HD in a particular year divided by the total number of patients starting that year. Transplant rate was defined as the number of patients transplanted within a particular year divided by the total number of patients starting that year. For this analysis, causes of transfer were grouped in broad categories as follows: infection (peritonitis and catheter infection), catheter problem, inadequate dialysis (including ultrafiltration failure/fluid management issues), psychosocial causes, and other medical causes. Psychosocial causes included psychological and social/learning. The life-table method was used to compute estimates of actuarial patient and technique survival. Data were censored at the following events: switch to HD, transplantation, death, loss to follow-up, recovery of native renal function, with the exception of death for patient survival calculation, and the exception of switch to HD for technique survival calculation. Cox regression estimation was performed for patient and technique survival in order to take into account the relative effects of various risk factors. Adjustments for age, diabetic status, gender, center size, calendar year, patient type (new to dialysis vs transfer from HD), and PD submodality (APD vs CAPD) were performed where appropriate. Interval Poisson regression was used to examine temporal profile of effects of various parameters on survival. The model was adjusted S25

6 to a list of variables used in its entirety for overall adjusted rates, excluding the variable in question when it is the subject of the exploration (i.e., for the effect of diabetes, the model was adjusted for all other parameters but not diabetic status). Variables used in the model to calculate adjusted rates included age, diabetic status, modality (CAPD vs APD), center characteristics, and type of patient (new to dialysis vs transfer from HD). REFERENCES 1. Huisman RM, Nieuwenhuizen MG, Th de Charro F. Patient-related and centre-related factors influencing technique survival of peritoneal dialysis in The Netherlands. Nephrol Dial Transplant 2002; 17: Schaubel DE, Blake PG, Fenton SS. Effect of renal center characteristics on mortality and technique failure on peritoneal dialysis. Kidney Int 2001; 60: Schaubel DE, Blake PG, Fenton SS. Trends in CAPD technique failure: Canada, Perit Dial Int 2001; 21: Jager KJ, Merkus MP, Boeschoten EW et al. What happens to patients starting dialysis in the Netherlands? Neth J Med 2001; 58: Schaubel DE, Fenton SS. Trends in mortality on peritoneal dialysis: Canada, J Am Soc Nephrol 2000; 11: Blake PG. Trends in patient and technique survival in peritoneal dialysis and strategies: how are we doing and how can we do better? Adv Ren Replace Ther 2000; 7: Kawaguchi Y. Peritoneal dialysis as long-term treatment: comparison of technique survival between Asian and Western populations. Perit Dial Int 1999; 19(Suppl 2): S327 S Jager KJ, Merkus MP, Dekker FW et al. Mortality and technique failure in patients starting chronic peritoneal dialysis: results of The Netherlands Cooperative Study on the Adequacy of Dialysis. NECOSAD Study Group. Kidney Int 1999; 55: Thome FS, Rodrigues AT, Bruno R et al. CAPD in southern Brazil: an epidemiological study. Adv Perit Dial 1997; 13: Heaf JG, Lokkegaard H, Madsen M. Initial survival advantage of peritoneal dialysis relative to haemodialysis. Nephrol Dial Transplant 2002; 17: Fox JG, Fowler I, Boulton-Jones JM. Audit of a decade of continuous ambulatory peritoneal dialysis. Nephrol Dial Transplant 1993; 8: Innes A, Burden RP, Morgan AG. Improvements in continuous ambulatory peritoneal dialysis technique survival: further experience from a UK renal unit. Perit Dial Int 1993; 13: Piraino B, Bernardini J, Holley JL, Perlmutter JA. A comparison of peritoneal dialysis-related infections in short- and long-term peritoneal dialysis patients. Perit Dial Int 1993; 13: Viglino G, Cancarini G, Catizone L et al. Ten years of continuous ambulatory peritoneal dialysis: analysis of patient and technique survival. Perit Dial Int 1993; 13(Suppl 2): S175 S Vonesh EF, Maiorca R. A multicenter, selection-adjusted comparison of patient and technique survival on CAPD and hemodialysis: a clarification. Perit Dial Int 1993; 13: de Fijter CW, Oe LP, Nauta JJ et al. Clinical efficacy and morbidity associated with continuous cyclic compared with continuous ambulatory peritoneal dialysis. Ann Intern Med 1994; 120: Jindal KK, Hirsch DJ. Excellent technique survival on home peritoneal dialysis: results of a regional program. Perit Dial Int 1994; 14: Lupo A, Tarchini R, Carcarini G et al. Long-term outcome in continuous ambulatory peritoneal dialysis: a 10-year-survey by the Italian Cooperative Peritoneal Dialysis Study Group. Am J Kidney Dis 1994; 24: Nolph KD. Technique survival in continuous ambulatory peritoneal dialysis. Perit Dial Int 1994; 14: Viglino G, Cancarini GC, Catizone L et al. Ten years experience of CAPD in diabetics: comparison of results with non-diabetics. Italian Cooperative Peritoneal Dialysis Study Group. Nephrol Dial Transplant 1994; 9: Genestier S, Hedelin G, Schaffer P, Faller B. Prognostic factors in CAPD patients: a retrospective study of a 10-year period. Nephrol Dial Transplant 1995; 10: McDonald M, McPhee PD, Walker RJ. Successful self-care home dialysis in the elderly: a single center s experience. Perit Dial Int 1995; 15: Saade M, Joglar F. Chronic peritoneal dialysis: seven-year experience in a large Hispanic program. Perit Dial Int 1995; 15: Bistrup C, Holm-Nielsen A, Pedersen RS. Technique survival and complication rates in a newly started CAPD center (five years of experience). Perit Dial Int 1996; 16: Lambert MC, Vijt D, De Smet R, Lameire N. Patient and technique survival after treatment shifts between CAPD and haemodialysis in a single centre. Edtna Erca J 1996; 22: 4 7, Maiorca R, Cancarini GC, Zubani R et al. CAPD viability: a long-term comparison with hemodialysis. Perit Dial Int 1996; 16: Wanten GJ, Koolen MI, van Liebergen FJ et al. Outcome and complications in patients treated with continuous ambulatory peritoneal dialysis (CAPD) at a single centre during 11 years. Neth J Med 1996; 49: Anderson JE. Ten years experience with CAPD in a nursing home setting. Perit Dial Int 1997; 17: Woodrow G, Turney JH, Brownjohn AM. Technique failure in peritoneal dialysis and its impact on patient survival. Perit Dial Int 1997; 17: Van Biesen W, Vanholder RC, Veys N et al. An evaluation of an integrative care approach for end-stage renal disease patients. J Am Soc Nephrol 2000; 11: Davies SJ. Peritoneal dialysis in the patient with a failing renal allograft. Perit Dial Int 2001; 21(Suppl 3): S280 S Utas C. Patient and technique survival on CAPD in Turkey. Perit Dial Int 2001; 21: Trivedi H, Tan SH, Prowant B et al. Predictors of death in patients on peritoneal dialysis: the Missouri Peritoneal Dialysis Study. Am J Nephrol 2005; 25: Bloembergen WE, Port FK, Mauger EA, Wolfe RA. A comparison of cause of death between patients treated with hemodialysis and peritoneal dialysis. J Am Soc Nephrol 1995; 6: Ganesh SK, Hulbert-Shearon T, Port FK et al. Mortality differences by dialysis modality among incident ESRD patients with and without coronary artery disease. J Am Soc Nephrol 2003; 14: Stack AG, Molony DA, Rahman NS et al. Impact of dialysis modality on survival of new ESRD patients with congestive heart failure in the United States. Kidney Int 2003; 64: Jaar BG, Coresh J, Plantinga LC et al. Comparing the risk for death with peritoneal dialysis and hemodialysis in a national cohort of patients with chronic kidney disease. Ann Intern Med 2005; 143: Cueto-Manzano AM, Quintana-Pina E, Correa-Rotter R. Long-term CAPD survival and analysis of mortality risk factors: 12-year experience of a single Mexican center. Perit Dial Int 2001; 21: Guo A, Mujais S. Patient and technique survival on peritoneal dialysis in the United States: evaluation in large incident cohorts. Kidney Int 2003; 64(Suppl 88): S3 S Vonesh EF, Snyder JJ, Foley RN, Collins AJ. The differential impact of risk factors on mortality in hemodialysis and peritoneal dialysis. Kidney Int 2004; 66: Xue JL, Chen SC, Ebben JP et al. Peritoneal and hemodialysis: I. Differences in patient characteristics at initiation. Kidney Int 2002; 61: Termorshuizen F, Korevaar JC, Dekker FW et al. Hemodialysis and peritoneal dialysis: comparison of adjusted mortality rates according to the duration of dialysis: analysis of The Netherlands Cooperative Study on the Adequacy of Dialysis 2. J Am Soc Nephrol 2003; 14: Fenton SS, Schaubel DE, Desmeules M et al. Hemodialysis versus peritoneal dialysis: a comparison of adjusted mortality rates. Am J Kidney Dis 1997; 30: Schaubel DE, Morrison HI, Fenton SS. Comparing mortality rates on CAPD/CCPD and hemodialysis. The Canadian experience: fact or fiction? Perit Dial Int 1998; 18: Collins AJ, Hao W, Xia H et al. Mortality risks of peritoneal dialysis and hemodialysis. Am J Kidney Dis 1999; 34: Selgas R, Cirugeda A, Fernandez-Perpen A et al. Comparisons of hemodialysis and CAPD in patients over 65 years of age: a meta-analysis. Int Urol Nephrol 2001; 33: Snyder JJ, Kasiske BL, Gilbertson DT, Collins AJ. A comparison of transplant outcomes in peritoneal and hemodialysis patients. Kidney Int 2002; 62: Schaubel DE, Stewart DE, Morrison HI et al. Sex inequality in kidney transplantation rates. Arch Intern Med 2000; 160: S26