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Elisabeth W Boeschoten

Publications and source records attributed to Elisabeth W Boeschoten.

At least 19 recordsLinked to original sources
PubMed2006

Social support predicts survival in dialysis patients.

BACKGROUND: Social support is a consistent predictor of survival, as evidenced in empirical studies in patients with cancer or cardiovascular disease. In the area of renal diseases, this topic has not yet been studied extensively. This study, therefore, aimed to investigate the association between social support and survival for patients on dialysis. METHODS: Between December 1998 and January 2002, 528 incident haemodialysis (HD) and peritoneal dialysis (PD) patients from multiple centres in The Netherlands were consecutively recruited as part of the NECOSAD-2 study. Patients completed the Social Support List (SSL) at 3 months after the start of dialysis. The SSL measured two aspects of social support: interaction and discrepancy. Cox regression analysis was used to estimate all-cause mortality risk from baseline till censor date on 1 January 2005. RESULTS: Perceiving a discrepancy between expected and received social support was associated with increased mortality: social companionship (RR(adj): 1.06, 95% CI: 1.00-1.13), daily emotional support (RR(adj): 1.10, 95% CI: 1.02-1.18), and total support (RR(adj): 1.02, 95% CI: 1.00-1.04). This association was similar for PD and HD patients. Social support (interaction) was not associated with survival, neither in the whole sample nor when stratified by therapy modality. CONCLUSIONS: These results point to the importance of psychosocial risk factors for mortality in patients on dialysis. More efforts are needed to improve support for these patients.

Female↗
PubMed2006

Mineral metabolism and cardiovascular morbidity and mortality risk: peritoneal dialysis patients compared with haemodialysis patients.

BACKGROUND: The K/DOQI guideline for bone metabolism and disease in chronic kidney disease is predominantly based on studies in haemodialysis (HD) patients. However, in clinical practice, this guideline is also applied to peritoneal dialysis (PD) patients. To validate the implementation of this guideline in PD patients, we evaluated the associations between plasma concentrations outside the K/DOQI-targets and the risk of cardiovascular morbidity and mortality in incident PD patients compared with HD patients. METHODS: In a large prospective multicentre study in the Netherlands (The Netherlands Cooperative Study on the Adequacy of Dialysis, NECOSAD), we included patients starting PD or HD between 1997 and 2004. Relative risk of cardiovascular morbidity and mortality were estimated using time-dependent Cox regression modelling. RESULTS: We included 586 PD patients with mean age 52 +/- 15 years (66% males) and 1043 HD patients with mean age 63 +/- 14 years (58% males). Cardiovascular disease (CVD) was the reason for hospitalization in 102 PD and 271 HD patients. In HD patients, the relative risk of CVD-related hospitalization increased with elevated plasma calcium concentrations (hazard ratio: 1.4; 95% CI: 1.1-1.9). Cardiovascular mortality was significantly higher for phosphorus concentrations above the K/DOQI-threshold in PD (2.4; 95% CI: 1.3-4.2) and HD patients (1.5; 95% CI: 1.1-2.1), and for elevated Ca x P in PD (2.2; 95% CI: 1.3-3.8) and HD patients (1.5; 95% CI: 1.1-2.1). CONCLUSIONS: Plasma calcium concentrations above the K/DOQI-threshold increase the relative risk of CVD-related hospitalization in HD patients. Associations with cardiovascular mortality were more pronounced. Both in PD and HD patients with elevated plasma phosphorus and Ca x P concentrations, the cardiovascular mortality risk is increased. Therefore, it seems appropriate to adopt the current guideline in PD patients.

Biomarkers↗
PubMed2006

The effect of single and repeatedly high concentrations of C-reactive protein on cardiovascular and non-cardiovascular mortality in patients starting with dialysis.

BACKGROUND: Single measurements of C-reactive protein (CRP) predict cardiovascular mortality in dialysis patients. However, CRP can be temporarily elevated due to infections. Therefore, we investigated the effect of single and repeatedly high concentrations of CRP on cardiovascular and non-cardiovascular mortality in incident dialysis patients. METHODS: In the Netherlands Cooperative Study on the Adequacy of Dialysis (NECOSAD), patients starting with dialysis were enrolled between 1997 and 2002. From 635 patients, plasma CRP concentrations were determined at 3 and 6 months of follow-up. Concentrations >10 mg/l were regarded as 'high'. Patients were followed until time of death, or censored at the end of follow-up (1 May 2004). Cox regression models were performed to compare mortality between patients with repeatedly low CRP, with varying CRP and with repeatedly high CRP. RESULTS: At the end of follow-up, 247 patients had died, of which 107 patients died of cardiovascular disease (47.8%). Patients with low CRP(3 months) and high CRP(6 months) were at increased cardiovascular [adjusted hazard ratio (HR): 2.59, 95% CI: 1.25-5.37] and non-cardiovascular (adjusted HR: 2.18, 95% CI: 1.11-4.28) mortality risk compared with patients with low CRP on both occasions. Moreover, patients with high CRP on both occasions had a higher cardiovascular (adjusted HR: 1.51, 95% CI: 0.72-3.18) and non-cardiovascular (adjusted HR: 2.25, 95% CI: 0.96-5.28) mortality risk than patients with high CRP(3 months) and low CRP(6 months). CONCLUSIONS: Single and repeatedly high concentrations of CRP (>10 mg/l) are related to both cardiovascular and non-cardiovascular mortality in dialysis patients. A high CRP concentration, therefore, has implications for the treatment of cardiovascular as well as non-cardiovascular disease.

C-Reactive Protein↗
PubMed2006

Serum troponin T concentration as a predictor of mortality in hemodialysis and peritoneal dialysis patients.

BACKGROUND: Troponin T is a good predictor of all-cause and cardiovascular mortality in cardiac patients. Although it is known that troponin T is an independent risk factor in dialysis patients as well, its prognostic value when measured routinely in clinical practice, particularly in addition to other risk indicators, is unclear. METHODS: A cohort of 847 patients who started dialysis therapy between 1997 and 2001 and participated in a multicenter follow-up study was examined. Clinical data were determined 3 months after the start of dialysis therapy. Patients were followed up until date of death or censoring in November 2003. RESULTS: For patients with troponin T values of 0.05 to 0.10 microg/L, hazard ratio for all-cause mortality was 2.2 (95% confidence interval [CI], 1.7 to 2.8) compared with patients with values less than 0.05 microg/L. For patients with values greater than 0.10 microg/L (11%), hazard ratio was 3.3 (95% CI, 2.5 to 4.5). A survival model with clinical and laboratory risk indicators yielded an area under the curve of 0.81, which did not increase when troponin T level was added to the model. The area under the curve for troponin T level alone was 0.67. No important differences were found between patients on hemodialysis or peritoneal dialysis therapy and between patients with high and low residual renal function. CONCLUSION: Although troponin T level is an independent risk factor for mortality in dialysis patients, it has limited added predictive power as a routine screening test over other clinical risk factors in dialysis patients.

Female↗
PubMed2006

Peritoneal dialysis-related infections recommendations 2005--an important tool for quality improvement.

Adequate performance measurement should be based on evidence-based guidelines. The recently published update of the International Society for Peritoneal Dialysis recommendations for peritoneal dialysis-related infections provides an opportunity to define a limited set of quality indicators as suitable for performance measurement and useful as targets for the improvement of dialysis care. Suitable quality indicators seem the incidence of peritonitis (target less than one episode every 18 months) and the percentage of culture-negative episodes (<20%). The lack of uniformity in definitions and the lack of studies providing evidence for firm recommendations are major limitations for further improvements in prevention, diagnosis and outcome of peritoneal dialysis-related infectious complications.

Humans↗
PubMed2005

The Kidney Disease Outcomes Quality Initiative (K/DOQI) Guideline for Bone Metabolism and Disease in CKD: association with mortality in dialysis patients.

BACKGROUND: In 2003, the National Kidney Foundation-Kidney Disease Outcomes Quality Initiative (K/DOQI) published a guideline recommending tight control of serum calcium, phosphorus, calcium-phosphorus product (Ca x P), and intact parathyroid hormone levels in patients with chronic kidney disease. Within the context of this guideline, we explored associations of these plasma concentrations with all-cause mortality risk in incident dialysis patients in The Netherlands. METHODS: In a large, prospective, multicenter, cohort study (Netherlands Cooperative Study on the Adequacy of Dialysis), we included 1,629 patients new on hemodialysis or peritoneal dialysis therapy between 1997 and 2004. Multivariate Cox regression models containing calcium level, phosphorus level, intact parathyroid hormone level, age, comorbidity, primary kidney disease, nutritional status, albumin level, dialysis dose, and hemoglobin level were used to examine mortality risks. RESULTS: Mean age was 60 +/- 15 (SD) years, 61% were men, and 64% were treated with hemodialysis. In adjusted time-dependent survival analysis, all-cause mortality risk increased in hemodialysis patients by 40% (hazard ratio [HR], 1.4; 95% confidence interval [CI], 1.1 to 1.7) and in peritoneal dialysis patients by 60% (HR, 1.6; 95% CI, 1.1 to 2.4) for plasma phosphorus levels greater than the target. In addition, having elevated plasma Ca x P product levels increased mortality risk by 40% (HR, 1.4; 95% CI, 1.1 to 1.8) in hemodialysis patients and 50% in peritoneal dialysis patients (HR, 1.5; 95% CI, 1.0 to 2.2). In both patient groups, no significant effects were observed for plasma levels less than the targets. CONCLUSION: In time-dependent survival analysis, the presence of plasma phosphorus and Ca x P product concentrations greater than K/DOQI targets increased all-cause mortality risk in hemodialysis and peritoneal dialysis patients.

Aged↗
PubMed2005

Incidence of recombinant erythropoietin (EPO) hyporesponse, EPO-associated antibodies, and pure red cell aplasia in dialysis patients.

BACKGROUND: Since 1998, an increase of anti-erythropoietin (anti-EPO) antibody-induced pure red cell aplasia (PRCA) has been reported. As data up to now consisted mostly of spontaneously reported cases the question arose about the frequency of this increase in EPO-induced PRCA. The objectives of this study were to determine the incidence and causes of recombinant EPO hyporesponse, of antibodies to EPO in patients on dialysis, and to relate the detection of anti-EPO antibodies to the presence of PRCA. METHOD: This multicenter cohort study used existing patient data and serum samples collected at 6-month intervals from 1677 patients with incident end-stage renal disease (ESRD) participating in The Netherlands Cooperative Study on the Adequacy of Dialysis-2 (NECOSAD-2). RESULTS: Fifty-seven patients had an inadequate EPO response, which resulted in an incidence of 16.7 per 1000 patient-years on EPO while on dialysis. All available sera specimens (N = 232) of these patients were screened for anti-EPO antibodies. The sera specimens of two of these 57 patients tested positive. Of the 57 patients with inadequate EPO response, one had clinical PRCA (incidence 0.29 per 1000 patient-years on EPO and on dialysis). Of the 1346 patients without symptoms of inadequate EPO response, one patient tested borderline positive for anti-EPO antibodies. In total, three patients developed EPO antibodies during follow-up, leading to an estimated incidence of 1.27/1000 (95% CI 0.3 to 3.7/1000) patient-years since the start of dialysis. CONCLUSION: The incidence of inadequate EPO response in our population of dialysis patients is in concordance with tentative calculations found in the literature. Furthermore, we found the incidence of EPO-induced PRCA and EPO antibodies to be low.

Adult↗
PubMed2005

ACE I/D polymorphism is associated with mortality in a cohort study of patients starting with dialysis.

BACKGROUND: In dialysis patients, only a few follow-up studies have addressed the relationship between the insertion/deletion (I/D) polymorphism in the angiotensin-converting enzyme (ACE) gene and mortality, but the available data are contradictory. METHODS: A cohort of 453 consecutive patients starting dialysis between January 1999 and January 2002 and participating in a Dutch multicenter prospective study was examined. Patients who died within 3 months after the start of dialysis were excluded. Patients were followed until date of death or censoring in November 2003. RESULTS: The ACE II, ID, and DD genotype frequencies were 24.3% (N = 110), 50.1% (N = 227), and 25.6% (N = 116). Besides a slightly higher number of Caucasians in the DD group, all other patient characteristics of the 3 ACE groups were similar at the start of dialysis. After adjustment for age, comorbidity, and ethnic background, patients with the ID and DD genotype showed an increased hazard ratio (HR) for all-cause mortality of 1.55 (95% CI 1.00-2.42) and 2.30 (95% CI 1.41-3.75), compared to patients with the II genotype. Slightly lower HRs were found for cardiovascular mortality. All groups of primary kidney disease showed a 2- to 3-fold increased adjusted HR for DD. CONCLUSION: The DD genotype identifies dialysis patients at an increased risk for mortality.

Aged↗
PubMed2005

When to start dialysis treatment: where do we stand?

BACKGROUND: Since the publication of opinion-based guidelines regarding the timing of dialysis treatment, there has been a trend toward earlier initiation. OBJECTIVE: In this review, the existing guidelines and the currently published studies that evaluate them are discussed. RESULTS: These studies could not demonstrate a clear benefit on survival or quality of life for patients who started with relatively higher renal function. CONCLUSION: Early start of dialysis treatment should not be confused with early referral to the nephrologist. It is concluded that initiation of dialysis should not depend on a predefined magnitude of renal function, but should be tailored to the individual patient.

Humans↗
PubMed2004

The effect of contraindications and patient preference on dialysis modality selection in ESRD patients in The Netherlands.

BACKGROUND: Patients with end-stage renal disease (ESRD) who are about to start long-term dialysis therapy are faced with the question of modality choice. The aim of the current study is to determine the influence of different factors on long-term dialysis modality choice. METHODS: As part of a large Dutch prospective multicenter study, the Netherlands Cooperative Study on the Adequacy of Dialysis, we consecutively included all new patients with ESRD. Nephrologists indicated the most important reason for the modality selection. RESULTS: Of 1,347 included patients, 36% (n = 483) had a contraindication to either peritoneal dialysis (PD) or hemodialysis (HD) therapy. Eighty percent (n = 386) of all contraindications were directed to PD therapy. The most frequently mentioned contraindication was a social one; ie, the expected incapability of patients to perform PD exchanges themselves. Patients with contraindications were older, had more comorbidity, and lived alone more often compared with patients without contraindications. In patients without contraindications (64%), modality choice was based on patient preference. Older age increased the odds of choosing HD, whereas receipt of predialysis care was associated with a lower preference for HD. CONCLUSION: Older age was associated with more contraindications to PD therapy and stronger patient preference for HD therapy. An elderly patient therefore was more likely to start with HD therapy. Results from the current study suggest that an increase in provision of predialysis care, in combination with a reduction in social contraindications to PD therapy, may be associated with an increase in likelihood of starting with PD therapy. In a time of an aging population, increasing demand on dialysis capacity, and limited amount of financial supplies, we may reconsider current strategies to provide future patients with ESRD the possibility to start with the dialysis modality they prefer.

Adult↗
PubMed2004

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.

Adult↗
PubMed2004

Effect of an increase in C-reactive protein level during a hemodialysis session on mortality.

The prevalence of chronic inflammation is high in dialysis patients. Moreover, it is associated with an increased mortality risk, yet the origin of chronic inflammation in dialysis patients remains unclear. The aim of this study was to determine the effect of a hemodialysis session (HD) on C-reactive protein (CRP) levels and to study the relation with survival. As part of a large, prospective, multicenter study in the Netherlands (Netherlands Cooperative Study on the Adequacy of Dialysis), patients who were started on dialysis treatment between September 1997 and May 1999 were included. Demographic data, clinical data, and serum samples were collected at regularly timed intervals. From this cohort, a random sample of patients was taken. CRP levels were determined before and after an HD session and before the next session. Date of death or censoring was recorded until September 2002. A total of 186 HD patients were included. Mean age was 65 yr (SD, 13); 56% were male. A total of 71 patients had a CRP level below the detection limit (3 mg/L), 68 patients showed no increase in CRP during an HD session (no-increase group), and 47 (25%) patients showed an increase in CRP level during an HD session (increase-group). No statistically difference in mean CRP levels before the dialysis session was found between the increase group (22.3 mg/L) and the no-increase group (19.4 mg/L). In the subsequent interdialytic period, CRP levels returned to the levels of the initial CRP value. Two-year survival was 44% in the increase group and 66% in the no-increase group (P = 0.09). Independent of CRP level before the session and adjusted for age, comorbidity, nutritional status, and primary kidney disease, a raise of 1 mg/L CRP during a session was associated with a 9% increased mortality risk (adjusted hazard ratio, 1.09; 95% CI, 1.02 to 1.16). The present study showed an increase in CRP level during a single dialysis session in 25% of the patients; during the succeeding interdialytic period, CRP level returned to its original value. More important, however, an increase in CRP level during an HD session was independently associated with a higher mortality risk.

Aged↗
PubMed2003

The relative importance of residual renal function compared with peritoneal clearance for patient survival and quality of life: an analysis of the Netherlands Cooperative Study on the Adequacy of Dialysis (NECOSAD )-2.

BACKGROUND: The guidelines from the US National Kidney Foundation Dialysis Outcomes Quality Initiative on peritoneal dialysis (PD) assume equivalence between the peritoneal and the renal solute clearance. The authors examined in a prospective cohort study of incident dialysis patients the relative contribution of residual renal function and peritoneal clearance to patient survival and quality of life (QoL). METHODS: The authors analyzed the longitudinal data on residual renal function, clearance by dialysis, and QoL of those patients who were treated with PD 3 months after the start of dialysis and participated in a prospective multicenter study in the Netherlands (n = 413). RESULTS: The mean age was 52 years, the mean residual glomerular filtration rate (rGFR) at 3 months was 4.1 mL/min/1.73 m2 (SD: 2.7), and the mean peritoneal creatinine clearance (pCrCl) at 3 months was 4.1 mL/min/1.73 m2 (SD: 1.1). The 2-year survival was 84%. For each mL/min/1.73 m2 increase in rGFR, a 12% reduction in mortality rate was found (relative risk of death [RR] = 0.88, P = 0.039). In contrast, no significant effect of pCrCl on patient survival was established (RR = 0.91, P = 0.47). The differential impact of rGFR and pCrCl was confirmed in an analysis on combined patient and technique survival and in an analysis on a number of generic and disease-specific dimensions of QoL. CONCLUSION: The beneficial effect of renal clearance and the absence of an effect of peritoneal clearance in the range of values common in current practice on patient outcome indicate that the 2 components of total solute clearance should not be regarded as equivalent. Higher peritoneal clearance targets do not necessarily improve patient outcome.

Adult↗
PubMed2003

Effect of starting with hemodialysis compared with peritoneal dialysis in patients new on dialysis treatment: a randomized controlled trial.

BACKGROUND: Up-until-now, the survival and health-related quality of life of hemodialysis and peritoneal dialysis patients has only been compared in observational studies. These studies have reported small and opposing differences between both modalities. The aim of this study was to compare the outcome of hemodialysis as initial chronic dialysis treatment with that of peritoneal dialysis in a randomized controlled trial. METHODS: All new dialysis patients from 38 dialysis centers in The Netherlands without indications against either modality were invited to participate. Patients were assigned to start with hemodialysis or peritoneal dialysis. The primary outcome was mean quality-adjusted life year (QALY) score. Secondary outcome was survival. RESULTS: Due to the low inclusion rate, the trial was prematurely stopped after which 38 patients had been randomized: 18 patients to hemodialysis and 20 to peritoneal dialysis. The mean QALY score in the first 2 years was 59.1 (SD 12) for hemodialysis patients versus 54.0 (SD 19) for peritoneal dialysis patients, which constitutes a small difference in favor of hemodialysis of 5.1 (95%CI -7.3 to 17.6) After 5 years of follow-up, nine hemodialysis and five peritoneal dialysis patients had died, a significant difference in survival; hazard ration of hemodialysis versus peritoneal dialysis of 3.8 (95%CI 1.1 to 12.6). After adjustment for age, comorbidity, and primary kidney disease the hazard ratio was 3.6 (0.8 to 15.4). CONCLUSION: Only a small difference in QALY score was observed between patients who started with hemodialysis compared to patients who started with peritoneal dialysis, lending support for the equivalence hypothesis. The significant difference in longer-term survival, which favored peritoneal dialysis in this small group of patients, could be used to posit that incident dialysis patients might benefit from starting on peritoneal dialysis.

Aged↗
PubMed2003

Time trends in initiation and dose of dialysis in end-stage renal disease patients in The Netherlands.

BACKGROUND: The guidelines published by the NKF-Dialysis Outcomes Quality Initiative (DOQI) in 1997 advocate an earlier start of dialysis in ESRD patients and a higher dialysis dose than usual. We studied the possible influence of the increasing emphasis on adequate dialysis on the management of ESRD patients in The Netherlands in 1993-2000. METHODS: The NECOSAD study on the adequacy of dialysis started in 1993. This prospective multi-centre study included ESRD patients older than 18 years who started HD or PD as the first RRT. We analysed the distribution of age, gender, primary renal disease and co-morbidity, the mean residual renal function and the mean dialysis-Kt/V(urea) at 3 months in 1569 consecutive patients by calendar year of initiation dialysis. RESULTS: Age, gender, primary renal disease and number of co-morbid conditions at the start of dialysis remained stable over time between 1993 and 2000. The mean renal Kt/V(urea) at 3 months increased from 0.5 in 1993 to 0.8 per week in 2000 (P<0.01). An upward trend remained after adjustment for patient characteristics and dialysis centre. The total Kt/V(urea) at 3 months increased from 3.3 in 1993 to 3.7 per week in 2000 in HD (P<0.01) and from 2.0 in 1993 to 2.3 per week in 1999 in PD patients (P<0.01). An upward trend in the dialysis-Kt/V(urea) was found after adjustment for renal Kt/V(urea) (HD: +0.3 per week, P=0.06; PD, +0.2 per week, P<0.05). CONCLUSIONS: These results indicate a tendency towards earlier introduction of RRT and higher doses of dialysis in The Netherlands. Possible effects of this development on mortality, morbidity, quality of life and the balance between costs and benefits need further investigation.

Adult↗
PubMed2003

Adjustment for comorbidity in studies on health status in ESRD patients: which comorbidity index to use?

Health status can be an important outcome in studies on patients with end-stage renal disease (ESRD). In these studies, adjustment for prognostic factors, such as comorbidity, often has to be made. None of the comorbidity indices that are commonly used in research on ESRD patients has been validated for studies on health status. This study evaluated three existing indices (Khan, Davies, and Charlson) and four indices specifically developed for use in studies on health status. In a large prospective multi-center study (NECOSAD-2), new ESRD patients were included (n = 1041). Comorbidity was assessed at the start of dialysis. Health status was assessed with the physical and mental component summary score of the SF-36 (PCS and MCS), the symptoms dimension of the KDQOL-SF, and the Karnofsky Scale. Patient data were randomly allocated to a modeling or a testing set. The new indices were developed in the modeling set. The three existing indices explained about the same percentage of variance in the PCS (7 to 8%), MCS (1 to 3%), symptoms (2 to 4%), and Karnofsky (10 to 12%). The new indices performed better than the existing indices in the modeling population (13% PCS, 10% MCS, 10% symptoms, 18% Karnofsky), but not in the testing population (8% PCS, 1% MCS, 3% symptoms, 8% Karnofsky). Individual comorbidities explained more variance in PCS (10 to 15%), MCS (1 to 7%), symptoms (6 to 11%), and Karnofsky (11 to 18%) than comorbidity indices. The Khan, Davies, and the Charlson indices will adjust to the same extent for the potential confounding effect of comorbidity in studies with health status as an outcome. Separate comorbidity diagnoses will adjust best for comorbidity.

Aged↗
PubMed2003

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.

Adult↗