Quality of life over time in dialysis: the Netherlands Cooperative Study on the Adequacy of Dialysis. NECOSAD Study Group.

BACKGROUND: Information on the longitudinal quality of life (QL) of patients treated by different dialysis modalities is lacking. Therefore, we performed a prospective cohort study on the QL over time in hemodialysis (HD) and peritoneal dialysis (PD) patients. METHODS: New chronic dialysis patients from 13 Dutch dialysis centers were consecutively included. The patients' self-assessment of QL was measured with the SF-36 form at 3, 6, 12, and 18 months after the start of dialysis treatment. RESULTS: Out of 230 patients who completed the QL questionnaire at least once, 139 patients stayed on their initial dialysis modality, 26 patients switched dialysis modality, 35 patients were transplanted, 28 patients died, and two patients had a recovery of renal function. The QL of patients who died during the study period was considerably worse at baseline and worsened at a faster rate than in the other patient groups. In patients who stayed on their initial dialysis modality, the physical QL decreased over time, whereas the mental QL tended to remain stable. After an adjustment for the initial value of QL and comorbidity, a consistently favorable effect of HD on physical QL over time was found compared with PD, whereas mental QL values remained similar. Parameters of adequacy of dialysis were not associated with QL over time. CONCLUSION: This prospective cohort study shows that physical QL over time in HD patients is better than in PD patients.     

Physical symptoms and quality of life in patients on chronic dialysis: results of The Netherlands Cooperative Study on Adequacy of Dialysis (NECOSAD)

BACKGROUND: So far, little attention has been paid to the value of dialysis adequacy for patients' quality of life (QL). Therefore we studied the impact of demographic, clinical, and dialysis characteristics on physical symptoms and perceived QL. METHODS: The study population consisted of 120 incident chronic haemodialysis (HD) and 106 peritoneal dialysis (PD) patients, starting dialysis treatment in 13 Dutch centres. Data were collected 3 months after the start of dialysis. Nine physical symptoms were assessed with a self-administered questionnaire. Patient's self-assessment of QL was measured with the 36-item MOS Short Form (SF-36). RESULTS: The most common symptoms in HD and PD were fatigue (respectively 82 and 87%) and itching (73 and 68%). In HD only a medium to high comorbidity--age risk index was associated with greater symptom burden. In PD also a lower percentage lean body mass, a lower rGFR, and past episodes of underhydration were associated with greater symptom burden. The explained variance by these variables was only 12% in HD and 21% in PD. However, greater symptom burden explained a substantial additional amount of impaired physical and mental QL on top of demographics and clinical status. Dialysis variables were associated neither with symptoms nor with QL. CONCLUSION: Symptom burden can be explained to a limited extent by demographic and clinical variables and not by dialysis characteristics. Addition of symptom burden to the other variables makes it possible to explain one-third of perceived QL. This underlines the importance of symptom reduction in order to improve patient's QL.     

Dialysis in The Netherlands: the clinical condition of new patients put into a European perspective. NECOSAD Study Group. Netherlands Cooperative Study on the Adequacy of Dialysis phase 1.

BACKGROUND: The unadjusted annual mortality rate among prevalent Dutch dialysis patients increased from 1981 to 1992. Part of this increase may be attributed to the ageing of the dialysis population, but hardly any data were available on other important prognostic features of new Dutch dialysis patients, such as co-morbidity and other aspects of their clinical condition. The aim of the present study was to obtain these data and to put them into a European perspective. METHODS: Two hundred and fifty consecutive new patients were included in this prospective multi-centre study. Data were collected 3 months after start of dialysis. Multivariate linear regression analysis was used to explain the variability of parameters of nutritional state and blood pressure. RESULTS: Mean age was 57 years, co-morbid conditions were present in 51%, diabetes mellitus in 18%, and cardiovascular disease in 28%. Decreased protein intake was related to diminished residual renal function. Our patients did not have more co-morbidity than Dutch patients participating in a European study some years earlier. Comparison with other studies was complicated by the use of different definitions of co-morbidity and of selected patient populations. CONCLUSIONS: Despite the fact that Dutch dialysis patients have become older and the incidence of diabetic nephropathy has increased, no conclusions could be drawn on a concomitant increase in co-morbidity. This patient group may serve as a reference population to study future changes in patient case-mix within the Netherlands. Furthermore, the use of common international definitions of co-morbidity is needed to be able to make comparisons of survival data.     

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

Various studies indicate that fair comparisons of mortality rates between hemodialysis (HD) patients and peritoneal dialysis (PD) patients are difficult because of differences in patient characteristics, because of nonconstant relative risks of death (RR), and because the survival times of patients who switch treatment modalities can be censored in different ways. The differences in mortality rates between HD and PD patients were investigated in an analysis in which these potential sources of bias were taken into account. The Netherlands Cooperative Study on the Adequacy of Dialysis is a multicenter, prospective, observational, cohort study in which new patients with ESRD are monitored until transplantation or death. A multivariate Cox regression analysis was used to analyze the mortality data according to treatment modality (HD, n = 742; PD, n = 480). No statistically significant differences in adjusted mortality rates between HD and PD patients were observed during the first 2 yr of dialysis. In the years thereafter, increases in mortality rates for PD patients and resulting decreases in RR in favor of HD were observed (e.g., months 24 to 36, adjusted RR, 0.53; 95% confidence interval, 0.31 to 0.91). This tendency was observed especially among patients >/=60 yr of age and was not influenced by the censoring strategy. These results suggest that long-term use of PD, especially among elderly patients, is associated with increases in mortality rates. Further analyses are required to determine the potential role of dialysis adequacy in the observed long-term differences in mortality rates between HD and PD patients and to establish the possible survival benefits for PD patients who switch to HD in time.     

Relative contribution of residual renal function and different measures of adequacy to survival in hemodialysis patients: an analysis of the Netherlands Cooperative Study on the Adequacy of Dialysis (NECOSAD)-2

A high delivered Kt/V(urea) (dKt/V(urea)) is advocated in the U.S. National Kidney Foundation Dialysis Outcomes Quality Initiative guidelines on hemodialysis (HD) adequacy, irrespective of the presence of residual renal function. The contribution of treatment adequacy and residual renal function to patient survival was investigated. The Netherlands Cooperative Study on the Adequacy of Dialysis is a prospective multicenter study that includes incident ESRD patients older than 18 yr. The longitudinal data on residual renal function and dialysis adequacy of patients who were treated with HD 3 mo after the initiation of dialysis (n = 740) were analyzed. The mean renal Kt/V(urea) (rKt/V(urea)) at 3 mo was 0.7/wk (SD 0.6) and the dKt/V(urea) at 3 mo was 2.7/wk (SD 0.8). Both components of urea clearance were associated with a better survival (for each increase of 1/wk in rKt/V(urea), relative risk of death = 0.44 [P < 0.0001]; dKt/V(urea), relative risk of death = 0.76 [P < 0.01]). However, the effect of dKt/V(urea) on mortality was strongly dependent on the presence of rKt/V(urea), low values for dKt/V(urea) of <2.9/wk being associated with a significantly higher mortality in anuric patients only. Furthermore, an excess of ultrafiltration in relation to interdialytic weight gain was associated with an increase in mortality independent of dKt/V(urea). In conclusion, residual renal clearance seems to be an important predictor of survival in HD patients, and the dKt/V(urea) should be tuned appropriately to the presence of renal function. Further studies are required to substantiate the important role of fluid balance in HD adequacy.     

Peritoneal transport properties and dialysis dose affect growth and nutritional status in children on chronic peritoneal dialysis. Mid-European Pediatric Peritoneal Dialysis Study Group.

To evaluate a possible effect of peritoneal transport properties and dialysis dose on the physical development of children on chronic peritoneal dialysis, a cohort of 51 children was prospectively followed for 18 mo. Peritoneal transport characteristics were assessed by serial peritoneal equilibration tests (PET), dialysis efficacy by dialysate and residual renal clearance measurements, and growth and nutritional status by the longitudinal changes (delta) of height SD score (SDS), body mass index (BMI) SDS, and serum albumin. delta height SDS was negatively correlated with the creatinine equilibration rate observed in the initial PET (r = -0.31, P < 0.05). Multiple regression analysis confirmed the negative effect of the high transporter state (partial r2 = 0.07), and disclosed an additional positive effect of dialytic C(Cr) (partial r2 = 0.11) and a weak negative effect of daily dialysate volume (partial r2 = 0.04) on delta height SDS. delta BMI SDS was strongly age-dependent (r = -0.48, P < 0.001); while relative body mass gradually increased below 4 yr of age, it remained stable in older children. Positive changes in BMI SDS were associated with rapid PET creatinine equilibration rates (univariate r = 0.35, P < 0.05) and/or large dialysate volumes (multivariate partial r2 = 0.11), suggesting a role of dialytic glucose uptake in the development of obesity. The change in serum albumin concentrations was positively correlated with dialysate volume (partial r2 = 0.14), and negatively affected by dialytic protein losses (partial r2 = 0.06). In conclusion, the peritoneal transporter state is a weak but significant determinant of growth and body mass gain in children on chronic peritoneal dialysis. Rapid small solute equilibration contributes to impaired growth but enhanced acquisition of body mass. Dialytic small solute clearance has a weak positive effect on statural growth independent of the transporter state, but does not affect body mass gain.     

Predictors of death in patients on peritoneal dialysis: the Missouri Peritoneal Dialysis Study

BACKGROUND: The study was designed to identify predictors of death in subjects on peritoneal dialysis (PD). METHODS: The population consisted of patients initiated on PD at the University of Missouri-Columbia and Dialysis Clinic Incorporated from January 1, 1990, through December 31, 1999. Baseline variables included demographics, clinical data, initial measures of nutritional status, adequacy, and transport characteristics. Co-morbidities were scored using a modified version of the Index of Coexistent Disease. Ongoing (during the course of PD) variables consisted of clinical characteristics and weighted time average of a number of laboratory, adequacy, and nutritional variables. The variables were screened using a univariate procedure, and then analyzed using stepwise logistic regression to evaluate their independent relation to death. RESULTS: There were 105 men and 86 women--180 Caucasians, 10 African-American, 1 Asian, mean age 61 +/- 13 (SD) years, and mean duration of follow-up 21 +/- 18 months. Eighty-two patients suffered the outcome of death. Lean body mass (LBM) at the initiation of PD was negatively associated with the risk of death (p < 0.01). In addition, the need for a partner to perform PD, total morbidity count, and the summated severity score of all co-morbidities were associated with an increased risk of death. The analysis of ongoing variables revealed that serum phosphate (negative association, p = 0.02) and number of hospitalization days per month on PD (p = 0.0006) were associated with an increased risk of death. CONCLUSION: Phosphate levels and LBM are strong negative predictors of death in PD subjects. Further, patients who need the assistance of a partner to perform PD have decreased survival.     

Patient-related and centre-related factors influencing technique survival of peritoneal dialysis in The Netherlands.

BACKGROUND: Although technique failure occurs relatively frequently in peritoneal dialysis (PD), few data have been published on differences in technique failure between centres. METHODS: Using data from RENINE, the comprehensive dialysis registry of The Netherlands, we analysed PD technique failure rates in the period 1994-1999, with life table methods and Cox multiple regression analysis. Patient age, sex, and the presence or absence of diabetes were included in the analysis, as well as time of initiation of PD and the following centre characteristics: number of PD patients treated in the centre and percentage of patients on PD. RESULTS: Technique failure was higher in older patients: 2-year technique survival was 75% in those younger than 45 years, 68% in the group aged 45-64 years, and 60% in those over 64 years (P<0.0001). Sex and diabetes made no difference in technique survival. Mean annual technique failure rates varied greatly between centres (10-59%) and correlated with the number of patients on PD in the centre (r=-0.396, P=0.009) and with the fraction of patients on PD (r=-0.410, P=0.006). Low technique survival rates occurred mainly in centres with less than 20 patients on PD: relative risk for technique failure 1.68 as compared with larger centres. Patients starting PD in the period 1997-1999 had better technique survival than those starting in 1994-1996 (P=0.001). CONCLUSION: PD technique survival in The Netherlands has increased in recent years. Having less than 20 PD patients in a centre or having a small fraction of patients on PD carries an increased risk of technique failure. The variability in PD technique survival between centres indicates that in many centres further improvements should be possible.     

Dialysis in diabetic patients: hemodialysis and peritoneal dialysis. Pros and cons

Both hemodialysis (HD) as well as peritoneal dialysis (PD), are efficient renal replacement therapies in uremic patients with and without diabetes. PD is less expensive dialysis modality and may provide a survival advantage over hemodialysis in first 2 to 4 years of treatment. Chronic ambulatory peritoneal dialysis (CAPD) as well as Continuous Cycler-Assisted Peritoneal Dialysis (CCPD) have additional advantages in patients with diabetes. PD therapy will be better tolerated than HD, the blood pressure is more stable and vascular access is not necessary. Preserving residual renal function (RRF) is of paramount importance to prolong the survival outcomes in PD patients. In insulin-dependent diabetic patients intraperitoneal insulin substitution can be used. The development of new, more biocompatible PD solutions holds promise for the future. Nevertheless, in many countries HD is further more favoured in the treatment of patients with ESRD.     

Pregnancy in patients on chronic ambulatory peritoneal dialysis.

Both conception and successful completion of pregnancy are rare occurrences in female patients on chronic renal replacement therapy. Only a handful of successful pregnancies and deliveries have been reported in patients receiving hemodialysis (HD). Even less common are reports of successful pregnancy and delivery in patients receiving chronic ambulatory peritoneal dialysis (CAPD). Among the more common causes of fetal loss are abruptio placentae and other causes of spontaneous miscarriage. We report here three cases of pregnancy in patients on CAPD; two of these pregnancies progressed successfully to spontaneous delivery, while the third terminated during an episode of acute peritonitis. Furthermore, we have reviewed the literature concerning the outcome of pregnancy in the dialysis population on CAPD.     

Severe vitamin D deficiency in chronic renal failure patients on peritoneal dialysis

The aim of this study was to evaluate the prevalence of vitamin D deficiency in chronic renal failure (CRF) patients on peritoneal dialysis (PD) and to correlate the findings with various demographic and renal osteodystrophy markers. METHOD: This cross-sectional, multicenter study was carried out in 273 PD patients with a mean age of 61.7 +/- 10.9 years and mean duration of PD 3.3 +/- 2.2 years. It included 123 female and 150 male patients from 20 centers in Greece and Turkey, countries that are on the same latitude, namely, 36-42 degrees north. We measured 25(OH)D3 and 1.25(OH)2D3 levels and some other clinical and laboratory indices of bone mineral metabolism. RESULTS: Of these 273 patients 92% (251 patients) had vitamin D deficiency i.e. serum 25(OH)D3 levels less than 15 ng/ml, 119 (43.6%) had severe vitamin D deficiency i.e., serum 25(OH)D3 levels, less than 5 ng/ml, 132 (48.4%) had moderate vitamin D deficiency i.e., serum 25(OH)D3 levels, 5-15 ng/ml, 12 (4.4%) vitamin D insufficiency i.e., serum 25(OH)D3 levels 15 - 30 ng/ml and only 10 (3.6%) had adequate vitamin D stores. We found no correlation between 25(OH)D3 levels and PTH, serum albumin, bone alkaline phosphatase, P, and Ca x P. In multiple regression analyses, the independent predictors of 25(OH)D3 were age, presence of diabetes (DM-CRF), levels of serum calcium and serum 1.25(OH)2D3. CONCLUSION: We found a high prevalence (92%) of vitamin D deficiency in these 273 PD patients, nearly one half of whom had severe vitamin D deficiency. Vitamin D deficiency is more common in DM-CRF patients than in non-DM-CRF patients. Our findings suggest that these patients should be considered for vitamin D supplementation.     

Meta-analysis: peritoneal membrane transport, mortality, and technique failure in peritoneal dialysis

Peritoneal membrane solute transport in peritoneal dialysis (PD) patients is assessed by the peritoneal equilibration test, which measures the ratio of creatinine in the dialysate to plasma after a standardized 4-h dwell (D/Pc). Patients then are classified as high, high-average, low-average, or low transporters on the basis of this result. A meta-analysis of observational studies was carried out to characterize the relationship between D/Pc and mortality and technique failure in patients who are on PD. Citations were identified in Medline by using a combination of Medical Subject Heading search terms and key words related to PD, peritoneal membrane permeability/transport, and mortality and technique failure. The table of contents of relevant journals and bibliographies of relevant citations were reviewed in duplicate. Twenty studies that met study criteria were identified. Nineteen studies were pooled to generate a summary mortality relative risk of 1.15 for every 0.1 increase in the D/Pc (95% confidence interval 1.07 to 1.23; P < 001). This result equated to an increased mortality risk of 21.9, 45.7, and 77.3% in low-average, high-average, and high transporters, respectively, as compared with patients with low transport status. Meta-regression analysis showed that the proportion of patients who were on continuous cycler PD within a study was inversely proportional to the mortality risk (P = 0.05). The pooled summary relative risk for death-censored technique failure was 1.18 (95% confidence interval 0.96 to 1.46; P = 0.12) for every 0.1 increase in the D/Pc. This meta-analysis demonstrates that a higher peritoneal membrane solute transport rate is associated with a higher mortality risk and a trend to higher technique failure.