Predictors of early mortality among incident US hemodialysis patients in the Dialysis Outcomes and Practice Patterns Study (DOPPS)

Hemoglobin variability and mortality: confounding by disease severity

BACKGROUND

Substantial variability in hemoglobin levels has been associated with increased mortality risk in hemodialysis patients. Variability also has been associated with concurrent comorbid conditions and hospitalization. Adequate adjustment for confounding by disease severity is needed to estimate the association of hemoglobin level variability with mortality risk.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

Medicare hemodialysis patients in 3 groups: prevalent on July 1, 2006 (n = 133,246), prevalent on July 1, 1996 (n = 78,602), and incident between January 1, 2005, and June 30, 2006 (n = 24,999).

PREDICTOR

Hemoglobin level variability estimated using the residual deviation around the linear trend in hemoglobin levels during a 6-month entry period.

OUTCOME

Time to death.

MEASUREMENTS

We fit Cox models of 1-year mortality with and without adjustment for disease severity (comorbid conditions, hospitalization days, and months with hemoglobin level <10 g/dL), measured concurrently with hemoglobin level variability.

RESULTS

Disease severity was associated positively with hemoglobin level variability in all groups. Before adjustment for disease severity, HRs for hemoglobin level variability were 1.27 (95% CI, 1.24-1.31) per 1 g/dL for patients prevalent in 2006, 1.32 (95% CI, 1.27-1.38) for patients prevalent in 1996, and 1.08 (95% CI, 1.03-1.13) for patients incident in 2005-2006. After adjustment, HRs for hemoglobin level variability were 1.02 (95% CI, 0.99-1.05), 1.07 (95% CI, 1.03-1.12), and 1.01 (95% CI, 0.95-1.06), respectively.

LIMITATIONS

We did not adjust for time-varying confounding of hemoglobin level; an inclusion requirement introduces potential selection bias; our findings may not apply to incident hemodialysis patients younger than 65 years; assessment of comorbid conditions from claims is subject to misclassification, with possible residual confounding attributable to comorbid conditions; this observational study cannot prove causality.

CONCLUSIONS

After adjustment for concurrent disease severity, evidence supporting an association between hemoglobin level variability and mortality risk was weak and inconsistent. The clinical utility of hemoglobin level variability may be limited.

Suboptimal initiation of dialysis with and without early referral to a nephrologist

BACKGROUND

Our objective was to examine patients who initiate renal replacement therapy (RRT) at 10 representative Canadian centers, characterize their initiation as inpatient or outpatient and describe their initial type of dialysis access, duration of pre-dialysis care and clinical status at the time of dialysis initiation. We also examined the impact of an optimal dialysis start (i.e. initiated as an outpatient with an arteriovenous fistula, arteriovenous graft or peritoneal dialysis catheter) on subsequent health outcomes.

METHODS

Charts of consecutive incident RRT patients were identified from 1 July to 31 December 2006. Information was collected until 6 months after the initiation or until death, transplant or transfer.

RESULTS

Three hundred and thirty-nine incident RRT patients were studied: 39.6% initiated as an inpatient; 54% started hemodialysis (HD) with a central venous catheter; 15.3% had <1 month predialysis care, while 64.6% had >1 year. Optimal starts occurred in 39.5% of patients. For HD patients, optimal starts occurred in 19.8%. Suboptimal starts were noted in patients referred <12 months prior to end-stage renal disease (44%) and in patients referred earlier (56%). The composite end point of death, transfusion or subsequent hospitalization was significantly reduced with an optimal start [hazard ratio 0.47 (95% confidence interval 0.32-0.68), P = 0.0001].

CONCLUSIONS

Suboptimal initiation of dialysis is common in patients referred early or late. The benefits of early referral are lost if dialysis is initiated suboptimally. There is a need to identify factors that lead to suboptimal initiation despite early referral.

The NKF-NUS hemodialysis trial protocol - a randomized controlled trial to determine the effectiveness of a self management intervention for hemodialysis patients

BACKGROUND

Poor adherence to treatment is common in patients on hemodialysis which may increase risk for poor clinical outcomes and mortality. Self management interventions have been shown to be effective in improving compliance in other chronic populations. The aim of this trial is to evaluate the effectiveness of a recently developed group based self management intervention for hemodialysis patients compared to standard care.

METHODS/DESIGN

This is a multicentre parallel arm block randomized controlled trial (RCT) of a four session group self management intervention for hemodialysis patients delivered by health care professionals compared to standard care. A total of 176 consenting adults maintained on hemodialysis for a minimum of 6 months will be randomized to receive the self management intervention or standard care. Primary outcomes are biochemical markers of clinical status and adherence. Secondary outcomes include general health related quality of life, disease-specific quality of life, mood, self efficacy and self-reported adherence. Outcomes will be measured at baseline, immediately post-intervention and at 3 and 9 months post-intervention by an independent assessor and analysed on intention to treat principles with linear mixed-effects models across all time points. A qualitative component will examine which aspects of program participants found particularly useful and any barriers to change.

DISCUSSION

The NKF-NUS intervention builds upon previous research emphasizing the importance of empowering patients in taking control of their treatment management. The trial design addresses weaknesses of previous research by use of an adequate sample size to detect clinically significant changes in biochemical markers, recruitment of a sufficiently large representative sample, a theory based intervention and careful assessment of both clinical and psychological endpoints at various follow up points. Inclusion of multiple dependent variables allows us to assess the broader impact on the intervention including both hard end points as well as patient reported outcomes. This program, if found to be effective, has the potential to be implemented within the existing renal services delivery model in Singapore, particularly as this is being delivered by health care professionals already working with hemodialysis patients in these settings who are specifically trained in facilitating self management in renal patients.

Chronic kidney disease as a risk factor for Clostridium difficile infection

INTRODUCTION

Clostridium difficile-associated diarrhoea (CDAD) is the most common cause of nosocomial diarrhoea in the USA. In this study, we sought to determine the association between chronic kidney disease (CKD) and CDAD.

METHODS

A case-control study was designed to determine the association between CKD and CDAD in an urban hospital. Over a 2-year period, all patients diagnosed with CDAD (n = 188) were included as cases and the prevalence of CKD was calculated. Age- and sex-matched patients without CDAD were considered as controls with a ratio of 2:1 controls to cases. The prevalence of different stages of advanced CKD (stages 3-5) was determined and compared between groups. Also the calculated odds ratios (OR) were adjusted for multiple possible confounding variables using logistic regression analysis.

RESULTS

There was no significant difference in prevalence of advanced CKD between cases and controls (OR = 1.38, 95% confidence intervals (CI) = 0.90-2.12, P = 0.1365). The association between CKD and CDAD remained insignificant in subjects with CKD stages 3-5 who were not on dialysis (OR = 1.07, 95% CI = 0.65-1.77), P = 0.7970). However, the group with end-stage renal disease on dialysis showed a significant association (OR = 2.60, 95% CI = 1.25-5.41, P = 0.0165). Controlling for antibiotics as a possible confounding variable, yielded an OR that was not statistically significant (OR = 2.05, 95% CI = 0.94-4.47, P = 0.07), but still showing a trend towards increased risk.

CONCLUSION

End-stage renal disease may increase the risk of acquiring CDAD through unknown mechanisms. This suggests implementing better surveillance strategies for these patients and eliminating the known risk factors for CDAD.

Hemodialysis arteriovenous fistula self-cannulation: moving theory to practice in developing patient-teaching resources

PURPOSE/OBJECTIVES

This article discusses how Orem's theory was applied to the revision of supporting documents in the patient-teaching process and subsequently the nurse's role in the patient's learning experience.

BACKGROUND/RATIONALE

Teaching based on didactic, provider-focused objectives is ineffective in meeting patient's learning needs. There is a lack of conclusive research on the development of appropriate patient-teaching endeavors for the acquisition of knowledge and skills related to the performance of hemodialysis arteriovenous fistula self-cannulation.

DESCRIPTION OF THE PROJECT/INNOVATION

To prepare patients for home hemodialysis, Orem's self-care-deficit nursing theory was used to guide the revisions of a patient assessment and learning documentation template, the development of a self-cannulation teaching resource and to foster a renewed sense of the nurse's role in the teaching process.

INTERPRETATION/CONCLUSION

The application of self-care-deficit nursing theory to the update and development of patient-teaching documentation and resources for self-cannulation provides the nurse with a theoretical approach to assess, plan, evaluate, and document teaching from a patient-focused perspective. Theory in practice provides a means to support and highlight the role of nurses in the patient-learning process. The utilization of practical activities to introduce theory into teaching provides a means to structure care processes and to enhance nurse's adoption of theory in practice.

IMPLICATIONS

Orem's theory provides a relevant, useful framework to guide nurses in teaching patients self-care. Research on the exploration of nurse's attitudes related to the benefit of adopting theory when teaching patients to perform hemodialysis self-care is needed.

Choice of vascular access among incident hemodialysis patients: a decision and cost-utility analysis

BACKGROUND AND OBJECTIVES

Arteriovenous fistulas (AVFs) are widely accepted as the preferred hemodialysis vascular access type. However, supporting data have failed to consider morbidity and mortality incurred during failed creation attempts and may therefore overstate potential advantages. This study compares survival, quality-adjusted survival, and costs among incident hemodialysis patients after attempted placement of AVFs or arteriovenous grafts (AVGs).

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Analogous Markov models were created, one each for AVF and AVG. Patients entered consideration at the time of first access creation, contemporaneous with dialysis initiation. Subsequent outcomes were determined probabilistically; transition probabilities, utilities, and costs were gathered from published sources. To ensure comparability between AVFs and AVGs, the timing and likelihood of access maturation were measured in a contemporary cohort of incident hemodialysis patients.

RESULTS

Mean (SD) overall survival was 39.2 (0.8) and 36.7 (1.0) months for AVFs and AVGs, respectively: difference (95% confidence interval [CI]) 2.6 (1.8, 3.3) months. Quality-adjusted survival was 36.1 (0.8) and 32.5 (0.9) quality-adjusted life months (QALMs) for AVFs and AVGs, respectively: difference (95% CI) 3.6 (2.8, 4.3) QALMs. The incremental cost-effectiveness ratio (95% CI) for AVFs relative to AVGs was $446 (-6023, 6994) per quality-adjusted life year saved.

CONCLUSIONS

AVFs are associated with greater overall and quality-adjusted survival than AVGs. Observed differences were much less pronounced than might be expected from existing literature, suggesting that prospective identification of patients at high risk for AVF maturational failure might enable improvements in health outcomes via individualization of access planning.

Who should be referred for a fistula? A survey of nephrologists

BACKGROUND

There is marked variation in the use of the arteriovenous fistula (AVF) across programmes, regions and countries not explained by differences in patient demographics or comorbidities. The lack of clear criteria of who should or should not get a fistula may contribute to this, as well as barriers to creating AVFs.

METHODS

We conducted a survey of Canadian and American nephrologists to assess the patient variables considered to determine the timing and type of access requested. Perceived barriers and absolute contraindications to access were also collected.

RESULTS

An immediate referral for a fistula was more highly preferred when patients are <65 years old, have minimal comorbidities or have no history of failed accesses. In older patients, and in those with increased comorbidities or a previously failed fistula, US nephrologists selected arteriovenous grafts as an alternative to the fistula, while Canadian nephrologists selected primarily catheters. Referral for vascular mapping was more common in the USA than in Canada. Gender did not influence the timing or the type of access. Perceived barriers to establishing a mature fistula included patient refusal for creation (77%) or cannulation (58%), delay in decision regarding dialysis modality (71%), wait time for surgical creation (55%) and high failure-to-mature rate (52%). We found that 27% of Canadian and 43% of American nephrologists indicated no absolute contraindications for permanent vascular access.

CONCLUSIONS

This study demonstrated marked variability in timing and criteria used to select patients for referral for a vascular access between nephrologists practicing within Canada and the USA. Establishing minimal eligibility criteria for fistulae is an important area of future research.

An integrative approach to advanced kidney disease in the elderly

Chronic kidney disease (CKD) has increasingly become a "geriatric" disease, with a dramatic rise in incidence in the aging population. Patients aged >75 years have become the fastest growing population initiating dialysis. These patients have increased comorbid diseases and functional limitations which affect mortality and quality of life. This review describes the challenges of dialysis initiation and considerations for management of the elderly subpopulation. There is a need for an integrative approach to care, which addresses management issues, health-related quality of life, and timely discussion of goals of care and end-of-life issues. This comprehensive approach to patient care involves the integration of nephrology, geriatric, and palliative medicine practices.

Meeting KDOQI guideline goals at hemodialysis initiation and survival during the first year

BACKGROUND AND OBJECTIVES

To determine, in a national cohort of incident hemodialysis patients, whether meeting a greater number of National Kidney Foundation Kidney Disease Outcomes Quality Initiative (KDOQI) guideline goals at dialysis initiation was independently associated, in a graded manner, with lower first-year mortality rates.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Patients who initiated hemodialysis between June 1, 2005, and May 31, 2007, in the US were included in this retrospective cohort analysis. Guidelines examined were (1) use of arteriovenous fistula or graft at initiation; (2) hemoglobin > or = 11 g/dl; and (3) albumin at goal. The primary predictor variable was number of guideline goals (zero, one, two, or three) met at dialysis initiation. Cox regression analysis was used to compare time to death, adjusting for baseline characteristics.

RESULTS

At dialysis initiation, 59%, 31%, 9%, and 1.6% of patients met zero, one, two, or three guideline goals, respectively (total n = 192,307). After multivariate adjustment, mortality hazard ratios (95% confidence intervals) were 0.81 (0.80 to 0.83) for patients who met one, 0.53 (0.51 to 0.56) for patients who met two, and 0.34 (0.30 to 0.39) for patients who met three guideline goals, compared with patients who met none. Meeting each individual goal was also associated with lower mortality.

CONCLUSIONS

These findings suggest a graded association between meeting a greater number of evidence-based guideline goals at dialysis initiation and lower risk of death during the first year on dialysis.

The "right" of passage: surviving the first year of dialysis

Mortality risk for dialysis patients is highest in the first year. We previously showed a 41% mortality benefit associated with a pilot case management program for incident hemodialysis patients (n = 918). The RightStart Program (RSP) provided prompt medical management and self-management education and was recently expanded to more facilities. We conducted a matched cohort analysis to validate the expanded program's continued effectiveness. Death risk was reduced for RS patients (n = 4308) versus matched controls (C; n = 4308) by 34% (hazard ratio = 0.66, P < 0.0001) at 120 d and 22% at 1 yr (hazard ratio = 0.78, P < 0.0001). RS patients had lower hospitalization during the first year (RS = 15.5 days per patient year versus C = 16.9, P < 0.01). At 120 d, more RS patients achieved hemoglobin 11 to 12 g/dl (RS = 22.4% versus C = 19.7%, P < 0.01), eKt/V > or = 1.2 (RS = 66% versus C = 53.5%, P < 0.01), albumin > or = 4.0 g/dl (RS = 26% versus C = 22%, P < 0.01), and phosphorus 3.5 to 5.5 mg/dl (RS = 52.4% versus C = 45.4%). At 120 d, RS patients had a greater reduction in catheter use (RS = 32% versus C = 25%, P < 0.01) and more vitamin D orders (RS = 60% versus C = 55%, P < 0.01). Expansion of RS to a larger incident patient population results in significant reduction of morbidity and mortality associated with improvement of intermediate outcomes.

Initiation of anaemia management in patients with chronic kidney disease not on dialysis in the Veterans Health Administration

BACKGROUND

Erythropoiesis-stimulating agents (ESAs) are frequently used to treat anaemia of chronic kidney disease (CKD) in the dialysis setting; however, few data are available regarding factors influencing initiation of ESAs and other therapies in non-dialysis patients.

METHODS

A retrospective cohort study of Veterans Health Administration data from 2003 to 2005 for 89 585 patients identified as having CKD and anaemia based on two outpatient estimated glomerular filtration rates <60 ml/min/1.73 m(2) and at least one outpatient haemoglobin (Hb) <11 g/dL. Hb levels, patient demographics, clinical and provider characteristics and procedures predicted ESA treatment initiation over 1 year of follow-up. Multivariable logistic and pooled logistic survival models identified predictors of ESA initiation.

RESULTS

Overall, 6381 subjects (7.1%) initiated ESAs within 1 year of the index Hb; initiation was more common (8.6%) for patients with Hb <10 g/dL. Iron therapy use varied by initial Hb levels (27.6% to 52.4%) as did transfusions (12.5% to 42.8%); each was more common at lower Hb levels. Hbs rose to above 11 g/dL for 25-50% of patients in the absence of any treatment or by transfusion/iron therapy. Factors predicting time to ESA initiation included: nephrologist [odds ratio (OR = 2.3)] or haematologist care (OR = 2.2) and iron therapy (OR = 1.6). Transfusions increased for patients with increasing follow-up time.

CONCLUSION

Iron therapy is more common than ESA treatment in patients with CKD and Hbs <11 g/dL in the VA. Correction of anaemia in the absence of any ESA treatment was common at higher Hbs levels, but much less so when Hb levels fell below 10 g/dL.

Hemodialysis in hypotensive heart failure using midodrine

BACKGROUND

Dialysis in patients with severe congestive heart failure and low blood pressure is difficult even in a hospital setting. We retrospectively recorded the effects and usefulness of an alpha (1) agonist in an outpatient dialysis unit in 5 patients with end-stage renal disease with symptomatic heart failure and low blood pressure. To provide outpatient dialysis, they were given midodrine before and during their dialysis sessions.

METHODS

The volume of fluid removed, the lowest blood pressure, and postdialysis blood pressure measurements were recorded during a 3- to 4-week period just before initiating therapy (control period) and were compared with the measurements while using midodrine (treatment period). The blood pressures were expressed as the average of the mean arterial pressures (MAP).

RESULTS

All patients had an increase in the lowest MAP during dialysis and in the postdialysis MAP. Each was significant at P = 0.03. Fluid removal was significant at P = 0.04. All the patients improved in their symptoms of orthopnea and shortness of breath.

CONCLUSION

Outpatient dialysis is possible and relieves the symptoms of congestive heart failure in patients with poor heart function, low blood pressure, and advanced age when midodrine is given immediately before and during the procedure.

Predicting six-month mortality for patients who are on maintenance hemodialysis

BACKGROUND AND OBJECTIVES

Prognostic information is rarely conveyed by nephrologists because of clinical uncertainty about accuracy. The objective of this study was to develop an integrated prognostic model of 6-mo survival for patients who receive hemodialysis (HD).

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A short-term prognostic model was developed using prospective data from a derivation cohort of 512 patients who were receiving HD at five dialysis clinics. Patient charts were reviewed for actuarial predictors (e.g., Charlson Comorbidity), and nephrologists answered the "surprise" question (SQ), "Would I be surprised if this patient died within the next 6 mo?" Survival was monitored for up to 24 mo. The prognostic model was tested with a validation cohort of 514 patients from eight clinics.

RESULTS

In a Cox multivariate analysis of the derivation cohort, five variables were independently associated with early mortality: Older age (hazard ratio [HR] for a 10-yr increase 1.36; 95% confidence interval [CI] 1.17 to 1.57), dementia (HR 2.24; 95% CI 1.11 to 4.48), peripheral vascular disease (HR 1.88; 95% CI 1.24 to 2.84), decreased albumin (HR for a 1-U increase 0.27; 95% CI 0.15 to 0.50), and SQ (HR 2.71; 95% CI 1.76 to 4.17). Area under the curve for the resulting prognostic model predictions of 6-mo mortality were 0.87 (95% CI 0.82 to 0.92) in the derivation cohort and 0.80 (95% CI 0.73 to 0.88) in the validation cohort.

CONCLUSIONS

An integrated 6-mo prognostic tool was developed and validated for the HD population. The instrument may be of value for researchers and clinicians to improve end-of-life care by providing more accurate prognostic information.

Care of the undocumented immigrant in the United States with ESRD

The growth of the undocumented immigrant population in the United States has been explosive. The absence of a uniform policy regarding health care for this population has created a unique problem for nephrologists. How should provision of care for undocumented immigrants with end-stage renal disease be delivered and compensated? This problem is exacerbated by the multiple complex laws that govern delivery of and payment for care, as well as that state regulations vary widely and are not easily understood. Furthermore, the ethical and moral commitments of providers to ensure adequate and appropriate care for any patient whose life is at stake, irrespective of his or her immigration status, place nephrologists in a difficult position. This review focuses on the scope of this problem, relevant case law and legislation, current care and payment models, the response of nephrology groups, and ethical dilemmas inherent in caring for this vulnerable population. Recommendations for further study, including convening of a consensus conference, are discussed.

Statins and vitamin D: a friendly association in pre-dialysis patients

The increased mortality rate observed in patients with chronic kidney disease is related to the high prevalence of cardiovascular disease in this population. Recently, it has been shown that interventional therapy with statins and/or vitamin D could improve the outcomes of these patients. The aim of this study was to identify the risk factors for mortality in a group of patients with chronic kidney disease (stages 4 and 5--pre-dialysis) and verify whether vitamin D and statins could change the outcome. We included 95 patients (mean age--69.4) with stages 4 and 5 (pre-dialysis) of our "low-clearance" outpatient clinic, with an average eGFR of 16.9 ml/min and a mean follow-up of 24.1 months. Several biological, nutritional, laboratory and inflammatory parameters were analysed at baseline. Our population was divided into three groups: G-I, patients not medicated with either vitamin D or statins; G-II, patients medicated with either vitamin D or statins; and G-III, patients medicated with vitamin D and statins. We found (ANOVA) that the serum levels of pre-albumin (P = 0.018) and PTH (P = 0.03) were lower in G-I. Concerning the inflammatory parameters, G-I showed higher levels of hsCRP (P = 0.014) and a trend to higher IL-6 levels (P = 0.077). We found the actuarial survival at 30 months (Kaplan-Meier), to be 56.4% in G-I, 82.3% in G-II and 100% in G-III (log rank = 13.08 P = 0.0014). Using the Cox proportional hazards model, we found that the existence of coronary artery disease (P = 0.0001) and the absence of medication with vitamin D and/or statins (P = 0.005) independently influenced the mortality of our patients. In conclusion, we found, in our study, that patients under vitamin D and statins (with a synergistic effect) were less inflamed and showed a lower mortality rate.

What's next after fistula first: is an arteriovenous graft or central venous catheter preferable when an arteriovenous fistula is not possible?

Findings from observational studies have established that the arteriovenous fistula (AVF) is the preferred form of vascular access for chronic hemodialysis. Unfortunately, in a subset of patients with end-stage renal disease, an AVF cannot be placed or fails to mature. In these patients an alternate form of vascular access, either an arteriovenous graft (AVG) or central venous catheter (CVC) must be selected. In this review we discuss the findings and limitations of studies examining the effect of access type (AVG or CVC) on clinical endpoints including mortality, quality of life, occurrence of infections, as well as the impact of the different access types on resource requirements. Specifically, we examine whether findings from previous studies are valid and applicable to patients for whom an AVF is not possible, and outline the need for future randomized clinical trials addressing this question.

Vascular access for dialysis: recent lessons and new insights

PURPOSE OF REVIEW

Vascular access complications are a major cause of excessive morbidity and mortality in the dialysis population. This review will focus on recent changes in vascular access practices and access management directly affecting patient outcomes.

RECENT FINDINGS

The proportion of patients dialyzing via arteriovenous fistulas continues to increase as a result of national initiatives. Maturation failure is now the main obstacle to successful use of fistulas. Arteriovenous grafts remain an important vascular access option for dialysis, and interventions to prevent progression of stenosis are being explored. Central venous catheter prevalence has increased and new interventions to address catheter-related complications such as thrombosis and infection are promising.

SUMMARY

Advances in understanding the factors related to fistula maturation failure will have a major beneficial effect on vascular access outcomes. New approaches to prevent graft and catheter-related complications should complement advances on fistula management. Optimal patient selection for specific access modalities and institution of timely access interventions tested in rigorous clinical trials should be the next step to improve access management.

Elevated osteoprotegerin is associated with all-cause mortality in CKD stage 4 and 5 patients in addition to vascular calcification

BACKGROUND

Cardiovascular disease is the leading cause of death in the chronic kidney disease (CKD) population. The mechanisms of vascular damage are not fully understood. The objective of this study was to prospectively investigate the importance of novel mediators of vascular damage, in conjunction with vascular calcification (VC), on survival.

METHODS

A total of 134 subjects [60 haemodialysis (HD), 28 peritoneal dialysis (PD) and 46 CKD stage 4] were studied. All survivors completed 40 months of follow-up. VC was measured using multi-slice spiral CT of the superficial femoral artery. Circulating osteoprotegerin (OPG), Fetuin-A and high sensitivity C-reactive protein (hs-CRP) were measured in addition to standard clinical biochemical analysis.

RESULTS

After a 40-month follow-up, 31 patients had died (27 men and 4 women). Of 31 subjects, 31 had evidence of significant VC. The majority of deaths were in the HD group (48%), 36% were PD subjects and 16% were CKD subjects. The outcome of interest was survival at the end of follow-up. Multivariate logistical regression analysis revealed male gender [OR 8.06 (1.34-48.450) P = 0.02], OPG >25 pmol/L [OR 5.31(1.35-20.88) P = 0.02] and hypoalbuminaemia [OR 0.26 (0.12-0.56) P < 0.01], were associated with increased odds of death.

CONCLUSION

We have previously reported that VC and low albumin predict death in CKD stages 4 and 5 over a 2-year follow-up period. These data show that OPG, independent of CRP, is also associated with a negative outcome. The mechanisms remain to be elucidated; however, it is likely that they are associated with vascular damage through mechanisms in addition to VC.

Multidisciplinary predialysis education decreases the incidence of dialysis and reduces mortality--a controlled cohort study based on the NKF/DOQI guidelines

BACKGROUND

Observational studies have demonstrated that multidisciplinary predialysis education (MPE) improves the post-dialysis outcomes of chronic kidney disease (CKD) patients. However, the beneficial effect of MPE remains unclear in prospective controlled studies.

METHODS

All CKD patients who visited the outpatient nephrology clinics at two centres of the Chang Gung Memorial Hospital in 2006-07 were enrolled. The incidence of dialysis and mortality were compared between MPE recipients and non-recipients. The content of the MPE was standardized in accordance with the NKF/DOQI guidelines. Prognostic factors for progression to end-stage renal disease (ESRD) and all-cause mortality were analysed by using the Cox proportional hazards model.

RESULTS

Of 573 patients, 287 received MPE. Dialysis was initiated in 13.9% and 43% of the patients in the MPE and non-MPE groups, respectively (P < 0.001). The mean follow-up period was 11.7 +/- 0.9 months. The overall mortality was 1.7% and 10.1% in the MPE and non-MPE groups, respectively (P < 0.001). Cox regression analysis revealed that diabetes, estimated glomerular filtration rate (eGFR), high-sensitive C-reactive protein (hs-CRP) and MPE assignment were significant independent predictors for progression to ESRD. Independent prognostic factors for mortality included age, diabetes, eGFR, hs-CRP and MPE assignment.

CONCLUSIONS

MPE based on the NKF/DOQI guidelines may decrease the incidence of dialysis and reduce mortality in late-stage CKD patients.

Complementary effects of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in slowing the progression of chronic kidney disease

Chronic kidney disease (CKD) and end-stage renal disease continue to pose major healthcare challenges. Early initiation of therapy aimed at slowing the progression of CKD is essential. Increased renin-angiotensin-aldosterone-system activity and, in particular, elevated levels of angiotensin II (AII) play important roles in the development and progression of CKD. Therefore, pharmacologic therapies that block the effects of AII and reduce its pathogenic effects are cornerstones of clinical management. Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) have been shown to have renoprotective effects in addition to their ability to control blood pressure. There is accumulating clinical evidence that the combination of an ACEI and an ARB provides greater renal protection, particularly in decreasing proteinuria, than does either agent alone.

Impact of metabolic syndrome and malnutrition on mortality in chronic hemodialysis patients

OBJECTIVE

Metabolic abnormalities contribute to increases in the mortality rate of patients on hemodialysis. Here, we estimate the importance and influence of metabolic syndrome and malnutrition on mortality rate.

DESIGN

This was a follow-up study.

METHODS

We examined the demographic characteristics of time on dialysis, body mass index, indications for hospitalization, treatment outcomes, and biochemical parameters over a 4-year period.

RESULTS

Whereas 31.7% of patients had metabolic syndrome, 26.7% showed evidence of malnutrition. More than two thirds of the malnourished patients died. Many patients (46%) with malnutrition were hospitalized because of problems with vascular access, whereas hospitalization of half of the examined patients with metabolic syndrome was attributable to cardiovascular disorders. Differences between groups in the parameters of anemia, total proteins, albumin, and low-density lipoprotein cholesterol also occurred, with the lowest values in malnourished patients. Glycemia, total cholesterol, and fibrinogen were significantly higher in patients with metabolic syndrome, whereas those with malnutrition had a markedly higher concentration of C-reactive protein. The mean survival was 24 months with metabolic syndrome and 17.5 months with malnutrition, which was significantly shorter.

CONCLUSIONS

More than half of the examined patients had metabolic abnormalities. Patients with malnutrition had a lower rate of survival compared with those who had metabolic syndrome. Two thirds of our malnourished patients died, and the total rate of mortality in the examined sample was 38%.

A clinical score to predict 6-month prognosis in elderly patients starting dialysis for end-stage renal disease

AIM

The aim of this study was to develop and validate a prognostic score for 6-month mortality in elderly patients starting dialysis for end-stage renal disease.

METHODS

Using data from the French Rein registry, we developed a prognostic score in a training sample of 2500 patients aged 75 years or older who started dialysis between 2002 and 2006, which we validated in a similar sample of 1642 patients. Multivariate logistic regression with 500 bootstrap samples allowed us to select risk factors from 19 demographic and baseline clinical variables.

RESULTS

The overall 6-month mortality was 19%. Age was not associated with early mortality. Nine risk factors were selected and points assigned for the score were as follows: body mass index <18.5 kg/m2 (2 points), diabetes (1), congestive heart failure stages III to IV (2), peripheral vascular disease stages III to IV (2), dysrhythmia (1), active malignancy (1), severe behavioural disorder (2), total dependency for transfers (3) and unplanned dialysis (2). The median score was 2. Mortality rates ranged from 8% in the lowest risk group (0 point) to 70% in the highest risk group (> or =9 points) and 17% in the median group (2 points). Seventeen percent of all deaths occurred after withdrawal from dialysis, ranging from 0% for a score of 0-1 to 15% for a score of 7 or higher.

CONCLUSIONS

This simple clinical score effectively predicts short-term prognosis among elderly patients starting dialysis. It should help to illuminate clinical decision making, but cannot be used to withhold dialysis. It ought to only be used by nephrologists to facilitate the discussion with the patients and their families.

Relevance of different antibody detection methods for the prediction of antibody-mediated rejection and deceased-donor kidney allograft survival

Presensitizing alloantibodies may represent a grave danger in organ transplantation, increasing the risk of antibody-mediated rejection (AMR) and graft loss. However, not all antibodies are harmful to the graft. In our study of a cohort of 325 deceased-donor renal allograft recipients, the patients were determined eligible to receive an allograft based on a negative complement-dependent cytotoxicity (CDC) crossmatch (XM). Yet at the time of transplantation, many candidates displayed donor-specific antibodies (DSA) by more sensitive methods, such as solid-phase assays (SPA, Luminex) or flow cytometry crossmatch (FCXM). The majority of the patients who were DSA positive by either SPA (67%) or FCXM (66%) presented an AMR-free clinical course posttransplantation. Among the patients who developed AMR (N = 29), 76% proved clinically manageable and did not lose the graft. Analysis of the DSA mean fluorescence intensities (MFI) of Luminex indicated no statistically significant difference between patients who experienced AMR episodes and those who did not. Importantly, many of the patients with AMR did not test positive for DSA by SPA (20/29) or FCXM (14/29). Despite false-positive and false-negative results, the detection of DSA by SPA or FCXM was positively associated with AMR, but not with actuarial graft survival. The field of organ transplantation has always struggled to reconcile two opposing goals: improving transplantation outcome while increasing access to transplantation. SPA and FCXM appear to be oversensitive and defining patients as "sensitized" according to these methods would block access to transplantation for many candidates who would otherwise benefit greatly from receiving the allograft. Nevertheless, SPA and FCXM are invaluable tools, assisting clinicians in gauging AMR risk and tailoring immunosuppression of the posttransplantation immunological monitoring accordingly.

Treatment center and geographic variability in pre-ESRD care associate with increased mortality

Late referral of patients with chronic kidney disease is associated with increased morbidity and mortality, but the contribution of center-to-center and geographic variability of pre-ESRD nephrology care to mortality of patients with ESRD is unknown. We evaluated the pre-ESRD care of > 30,000 incident hemodialysis patients, 5088 (17.8%) of whom died during follow-up (median 365 d). Approximately half (51.3%) of incident patients had received at least 6 mo of pre-ESRD nephrology care, as reported by attending physicians. Pre-ESRD nephrology care was independently associated with survival (odds ratio 1.54; 95% confidence interval 1.45 to 1.64). There was substantial center-to-center variability in pre-ESRD care, which was associated with increased facility-specific death rates. As the proportion of patients who were in a treatment center and receiving pre-ESRD nephrology care increased from lowest to highest quintile, the mortality rate decreased from 19.6 to 16.1% (P = 0.0031). In addition, treatment centers in the lowest quintile of pre-ESRD care were clustered geographically. In conclusion, pre-ESRD nephrology care is highly variable among treatment centers and geographic regions. Targeting these disparities could have substantial clinical impact, because the absence of > or = 6 mo of pre-ESRD care by a nephrologist is associated with a higher risk for death.

Conversion of vascular access type among incident hemodialysis patients: description and association with mortality

BACKGROUND

Limited data exist describing vascular access conversions during the first year on dialysis therapy or the effect of converting to and from a catheter on subsequent mortality risk.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

We studied a random sample of incident US hemodialysis patients (initiated long-term dialysis < 30 days before study entry) in the Dialysis Outcomes and Practice Patterns Study (DOPPS; 1996-2004).

PREDICTORS

At dialysis therapy initiation, we assessed vascular access type in use (arteriovenous fistula [AVF], arteriovenous graft [AVG], or catheter) and other patient characteristics. We characterized changes in vascular access type (conversions) by using regularly collected functional status information.

OUTCOME & MEASUREMENTS

We assessed time to all-cause mortality. We first described conversions, then used time-dependent Cox regression to estimate mortality hazard ratios (HRs) for conversions from a catheter to a permanent vascular access (versus no conversion) and conversions from a permanent vascular access to a catheter (versus no conversion).

RESULTS

The study included 4,532 patients; 69.2% were dialyzing with a catheter; 17.6%, with an AVG; and 13.1%, with an AVF. In patients initiating therapy with an AVF or AVG, 22% experienced a conversion (failure), and median times to first failure were 62 and 84 days, respectively. In catheter patients, 59% converted to an AVF/AVG (predominantly AVG [57%]); median times to first conversion were 92 and 66 days, respectively. Conversion to a permanent access was associated with an adjusted mortality HR of 0.69 (95% confidence interval, 0.55 to 0.85). The effect was similar for conversion to an AVF or AVG, and these persisted across demographic groups and facilities with different conversion practices. Conversion from a permanent vascular access to a catheter was associated with an adjusted mortality HR of 1.81 (95% confidence interval, 1.22 to 2.68).

LIMITATIONS

Potential for residual confounding because of unmeasured factors influencing decision to convert.

CONCLUSION

Vascular access conversions are common in incident patients. Continued efforts to increase early nephrologist referral and permanent vascular access placement may help decrease mortality risk in incident dialysis patients.

Effect of Epoetin alfa dose changes on hemoglobin and mortality in hemodialysis patients with hemoglobin levels persistently below 11 g/dL

BACKGROUND AND OBJECTIVES

The mortality risk associated with attempting to raise hemoglobin (Hb) levels by increasing Epoetin alfa (EPO) doses in hemodialysis patients with persistently low Hb remains poorly understood. Design, setting, participants, & measurements. We included hemodialysis patients from a large dialysis provider between July 2000 and June 2001 who had EPO dose and Hb data for 6 consecutive months, and a mean Hb <11 g/dl in months 4 to 6 (sub-11 period). We identify predictors of EPO dose changes during the sub-11 period; evaluate the proportion of patients achieving a Hb >or=11 g/dl after the sub-11 period by dose-change categories; and evaluate the association between EPO dose changes and mortality risk.

RESULTS

Patients were more likely to receive greater EPO dose increases if they had lower EPO doses, higher Hb levels, or were recently hospitalized. Greater EPO dose increases elevated the likelihood of achieving an Hb >or=11 g/dl in the subsequent 3 mo. Larger EPO dose changes over the sub-11 period were not associated with an elevated mortality risk, but having an Hb <9 g/dl at the end of that period independent of dose change was associated with mortality risk. We found that patients receiving larger dose changes and whose resulting Hb level remained <9.5 g/dl at the end of the 3 mo were at elevated mortality risk.

CONCLUSIONS

In patients with persistently low Hb levels, mortality risk was strongly associated with the patient's ability to achieve a hematopoietic response rather than the magnitude of EPO dose titrations.

Mortality Factor Survey of Severe Acute Respiratory Syndrome in Taiwan

Background

Severe acute respiratory syndrome (SARS) is a new respiratory tract infectious disease caused by the highly contagious coronavirus (SARS-CoV). Its propagation and symptom progress are very rapid. This study evaluated the clinical characteristics, laboratory results and mortality factors of probable SARS cases.

Methods

This study was adopted with a retrospective research design to study probable SARS cases from the Chang Gung Memorial Hospital in Linkou and Kaoshiung from August 2003 to February 2004, with a total of 78 cases (average age, 44 years; standard deviation, 18 years; age range, 13–84 years) including 24 males (30.8%) and 54 females (69.2%).

Results

Most of the 78 cases involved nosocomial infection (56.4%). A total of 24 patients died, and the mortality rate was as high as 30.8%. Logistic regression analysis found that intubation (odds ratio, 115; p < 0.001) was the mortality forecast factor.

Conclusion

The mortality rate of intubation patients was 115 times higher than that of those who did not require intubation. Therefore, special care must be taken with SARS disease with severe infiltration chest X-ray images and respiratory distress. Positive medical treatment should be performed to lower the mortality rate.

Recommendations for a clinical decision support for the management of individuals with chronic kidney disease

BACKGROUND AND OBJECTIVES

Care for advanced CKD patients is suboptimal. CKD practice guidelines aim to close gaps in care, but making providers aware of guidelines is an ineffective implementation strategy. The Institute of Medicine has endorsed the use of clinical decision support (CDS) for implementing guidelines. The authors' objective was to identify the requirements of an optimal CDS system for CKD management.

DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS

The aims of this study expanded on those of previous work that used the facilitated process improvement (FPI) methodology. In FPI, an expert workgroup develops a set of quality improvement tools that can subsequently be utilized by practicing physicians. The authors conducted a discussion with a group of multidisciplinary experts to identify requirements for an optimal CDS system.

RESULTS

The panel considered the process of patient identification and management, associated barriers, and elements by which CDS could address these barriers. The panel also discussed specific knowledge needs in the context of a typical scenario in which CDS would be used. Finally, the group developed a set of core requirements that will likely facilitate the implementation of a CDS system aimed at improving the management of any chronic medical condition.

CONCLUSIONS

Considering the growing burden of CKD and the potential healthcare and resource impact of guideline implementation through CDS, the relevance of this systematic process, consistent with Institute of Medicine recommendations, cannot be understated. The requirements described in this report could serve as a basis for the design of a CKD-specific CDS.

Facility hemodialysis vascular access use and mortality in countries participating in DOPPS: an instrumental variable analysis

BACKGROUND

Previously, the Dialysis Outcomes and Practice Patterns Study (DOPPS) has shown large international variations in vascular access practice. Greater mortality risks have been seen for hemodialysis (HD) patients dialyzing with a catheter or graft versus a native arteriovenous fistula (AVF). To further understand the relationship between vascular access practice and outcomes, we have applied practice-based analyses (using an instrumental variable approach) to decrease the treatment-by-indication bias of prior patient-level analyses.

STUDY DESIGN

A prospective observational study of HD practices.

SETTING & PARTICIPANTS

Data collected from 1996 to 2004 from 28,196 HD patients from more than 300 dialysis units participating in the DOPPS in 12 countries.

PREDICTOR OR FACTOR

Patient-level or case-mix-adjusted facility-level vascular access use. OUTCOMES/MEASUREMENTS: Mortality and hospitalization risks.

RESULTS

After adjusting for demographics, comorbid conditions, and laboratory values, greater mortality risk was seen for patients using a catheter (relative risk, 1.32; 95% confidence interval, 1.22 to 1.42; P < 0.001) or graft (relative risk, 1.15; 95% confidence interval, 1.06 to 1.25; P < 0.001) versus an AVF. Every 20% greater case-mix-adjusted catheter use within a facility was associated with 20% greater mortality risk (versus facility AVF use, P < 0.001); and every 20% greater facility graft use was associated with 9% greater mortality risk (P < 0.001). Greater facility catheter and graft use were both associated with greater all-cause and infection-related hospitalization. Catheter and graft use were greater in the United States than in Japan and many European countries. More than half the 36% to 43% greater case-mix-adjusted mortality risk for HD patients in the United States versus the 5 European countries from the DOPPS I and II was attributable to differences in vascular access practice, even after adjusting for other HD practices. Vascular access practice differences accounted for nearly 30% of the greater US mortality compared with Japan.

LIMITATIONS

Possible existence of unmeasured facility- and patient-level confounders that could impact the relationship of vascular access use with outcomes.

CONCLUSIONS

Facility-based analyses diminish treatment-by-indication bias and suggest that less catheter and graft use improves patient survival.

Use of darbepoetin alfa in the treatment of anaemia of chronic kidney disease: clinical and pharmacoeconomic considerations

The introduction of erythropoiesis-stimulating agents (ESAs) into everyday clinical practice has greatly improved the care of patients with chronic kidney disease. ESAs have reduced the need for blood transfusions, improved survival, decreased cardiovascular complications and enhanced patient quality of life. The longer acting ESA, darbepoetin alfa (Aranesp®), which can be administered less frequently than traditional ESAs, provides further benefits to both patients and healthcare professionals relative to the epoetins. Clinical studies have shown that darbepoetin alfa administered once every 2 weeks or once every month allows enhanced convenience and cost savings with no compromise in efficacy, while maintaining patients within target haemoglobin ranges.

A randomized, double-blind, placebo-controlled study to assess the efficacy and safety of cinacalcet HCl in participants with CKD not receiving dialysis

BACKGROUND

Secondary hyperparathyroidism is observed in patients with early chronic kidney disease (CKD). This study investigated the safety and efficacy of cinacalcet for secondary hyperparathyroidism in participants with CKD not receiving dialysis.

STUDY DESIGN

Double-blind, randomized, 32-week, phase 3 study.

SETTING & PARTICIPANTS

404 participants with stage 3 or 4 CKD from 73 centers in 9 countries.

INTERVENTIONS

Cinacalcet:placebo (3:1 ratio).

OUTCOMES & MEASUREMENTS

Proportion of participants with a mean decrease of 30% or greater in intact parathyroid hormone (iPTH) level, proportion with iPTH level of 70 or less or 110 or less pg/mL (stage 3 and 4 CKD, respectively), and mean percentage of iPTH change from baseline, all during the efficacy-assessment phase.

RESULTS

A greater proportion of cinacalcet than placebo participants achieved a 30% or greater decrease in iPTH level (74% versus 28%; P < 0.001), corresponding to a 43.1% decrease in iPTH level from baseline (cinacalcet) compared with a 1.1% increase (placebo). At week 32, serum calcium levels were 8.9 +/- 0.8 mg/dL (-8.9%; cinacalcet) and 9.9 +/- 0.6 mg/dL (+0.8%; placebo), phosphorus levels were 4.5 +/- 1.0 mg/dL (+21.4%) and 4.0 +/- 0.7 mg/dL (+6.8%), and calcium-phosphorus product values were 40.1 +/- 8.3 mg(2)/dL(2) (+18.9%) and 38.9 +/- 6.9 mg(2)/dL(2) (+17.1%), respectively. During the study course, 62% (cinacalcet) and 1% (placebo) of participants experienced 2 consecutive serum calcium concentrations less than 8.4 mg/dL. They generally were asymptomatic and without significant clinical consequences. Treatment generally was well tolerated, and most adverse events were mild to moderate in severity.

LIMITATIONS

The study was not designed to assess the effects of cinacalcet on vascular calcification, bone histomorphometric parameters, or other clinical outcomes. It is not known whether the observed differences in changes in iPTH levels are clinically more important than observed differences in changes in serum calcium or phosphorus levels or dosages of vitamin D sterols and phosphate binders.

CONCLUSIONS

These data show that cinacalcet treatment in patients with CKD not receiving dialysis can decrease plasma iPTH levels, but with frequent (albeit generally asymptomatic) serum calcium levels less than 8.4 mg/dL and increases in serum phosphorus levels.

Arteriovenous fistula use is associated with lower cardiovascular mortality compared with catheter use among ESRD patients

The arteriovenous fistula (AVF) is the recommended form of dialysis vascular access, however, limited studies suggest that AVF creation may result in increased cardiovascular stress and remodeling. To explore the contribution of vascular access type to cardiovascular-related (CV) mortality, we analyzed USRDS Clinical Performance Measures data comprising 4854 patients that initiated dialysis between October 1, 1999-December 31, 2004. CV mortality included death from acute myocardial infarction, atherosclerotic heart disease, cardiomyopathy, arrhythmia, cardiac arrest or stroke. Risk of cardiovascular mortality during a 4-year observation was analyzed by Cox-regression methods with adjustments for demographic and co-morbid conditions. AVF use was strongly associated with lower all-cause and CV mortality. After adjustment for covariates, AVF use 90 days after dialysis initiation remained significantly associated with lower cardiovascular mortality [hazard ratio (HR) 0.69, p = 0.0004] compared with catheter use. These findings suggest that vascular access type influences cause-specific mortality beyond that of infection, and support existing guidelines recommending the use of an AVF early in the course of chronic end-stage renal disease therapy.

Sequence variants in the PLEKHH2 region are associated with diabetic nephropathy in the GoKinD study population

Nephropathy is a common microvascular complication of diabetes with a genetic component for disease development. Genetic analyses have implicated multiple chromosomal regions for disease susceptibility but no single locus can account for the majority of the genetic component. Here, we report a genetic analysis of the PLEKHH2 gene that was identified through a single nucleotide polymorphism (SNP) genome-wide association study (GWAS) for association with the development of diabetic nephropathy (DN) in the Genetics of Kidneys in Diabetes (GoKinD) study population. We initially examined the GWAS results from a subset of the GoKinD singleton population based on the two most common HLA diplotypes consisting of 112 cases and 148 controls. We observed two-adjacent markers mapping to the PLEKHH2 locus, rs1368086 and rs725238, each associated at P < 0.001. Additional SNPs were selected for linkage disequilibrium mapping and transmission disequilibrium testing (TdT) in 246 case trio families. A single marker, rs11886047, located upstream of the PLEKHH2 promoter was associated with DN by TdT in the case trios (P = 0.0307), and there was a increase of heterozygous genotypes in cases, relative to controls, from the 601 case and 577 control GoKinD singleton case/control population (P = 0.00256). These findings suggest that PLEKHH2, which has mRNA and protein expression exclusively in the glomerulus, may be a genetic risk factor for susceptibility to DN in the GoKinD population.

Exploring relative mortality and epoetin alfa dose among hemodialysis patients

BACKGROUND

Confounding-by-indication is a bias in nonexperimental studies that occurs when outcomes are compared for treated and untreated patients and the treatment or medication dose is related to predictors of the outcome. Two recent publications reported that greater epoetin alfa (EPO) doses were associated with increased mortality rates. We assessed whether confounding-by-indication might account for these results.

STUDY DESIGN

We used a retrospective cohort study design.

SETTING & PARTICIPANTS

Hemodialysis patients were randomly selected from a large dialysis organization from July 2000 to June 2002 and were required to have completed a 9-month baseline period.

PREDICTOR

EPO dose assessed during months 7 to 9 of the baseline period and monthly throughout the follow-up period. Hemoglobin (Hb) was assessed as average value during months 4 to 6 of the baseline period and monthly throughout the follow-up period. All other covariates were assessed during months 1 to 6 of the baseline period.

OUTCOME

All-cause mortality during the 1 year of follow-up. Baseline Cox models were fitted with log EPO and Hb with and without adjustment for baseline patient characteristics. Time-dependent models were fitted with time-varying log EPO and Hb and, separately, lagged log EPO and Hb, with adjustment for baseline patient characteristics.

RESULTS

22,955 patients met our inclusion criteria. In the unadjusted model, we observed increased mortality risk with increasing EPO dose (hazard ratio [HR], 1.31 per log unit increase; 95% confidence interval [CI], 1.26 to 1.36). Adjustment for baseline patient characteristics resulted in an appreciably decreased HR (HR, 1.21; 95% CI, 1.15 to 1.28). In the lagged time-dependent analyses, estimates ranged from HR of 0.93 (95% CI, 0.92 to 0.95) to HR of 1.01 (95% CI, 0.99 to 1.03) for the 1- and 2-month lagged models, respectively.

LIMITATIONS

This analysis was limited to prevalent hemodialysis patients, and inhospital EPO dosing information was unavailable.

CONCLUSIONS

The observed mortality risk estimates associated with EPO dose in nonexperimental studies in dialysis patients may be highly sensitive to the analytic method used. This highlights the complexity of evaluating the association between EPO dose, Hb level, and mortality in these studies.

Early start peritoneal dialysis

The timing of commencement of dialysis is controversial, as it has an impact on the patient's lifestyle, the dialysis capacity of renal services, and costs to both the individual and community. In patients with chronic kidney disease, the commencement of dialysis based on clinical features of uremia and laboratory indices that mandate dialysis therapy may not optimize outcomes. Currently reported studies are subject to potential confounding factors, including lead-time bias, the timing of referral, uniform predialysis care, patient age, comorbidity, and compliance. Despite the lack of supporting evidence, national and international expert panels have generally recommended adopting guidelines that support the initiation of dialysis at levels of kidney function that are higher than observed in current practice. No compelling evidence supports the initial use of one modality of dialysis over another, but initiation of peritoneal dialysis will likely preserve residual kidney function to a greater extent than will initiation of hemodialysis. As preservation of endogenous kidney function is an important goal in patients with end-stage kidney disease, this outcome may contribute to the choice of modality. Objective parameters that will guide the initiation of dialysis to maximize survival, reduce morbidity, and inform as to the economic benefit of implementing such practice will be available when the Initiating Dialysis Early and Late (IDEAL) study reports in 2009.