Mortality among hemodialysis patients in Europe, Japan, and the United States: case-mix effects

Data-driven, two-stage machine learning algorithm-based prediction scheme for assessing 1-year and 3-year mortality risk in chronic hemodialysis patients

Life expectancy is likely to be substantially reduced in patients undergoing chronic hemodialysis (CHD). However, machine learning (ML) may predict the risk factors of mortality in patients with CHD by analyzing the serum laboratory data from regular dialysis routine. This study aimed to establish the mortality prediction model of CHD patients by adopting two-stage ML algorithm-based prediction scheme, combined with importance of risk factors identified by different ML methods. This is a retrospective, observational cohort study. We included 800 patients undergoing CHD between December 2006 and December 2012 in Shin-Kong Wu Ho-Su Memorial Hospital. This study analyzed laboratory data including 44 indicators. We used five ML methods, namely, logistic regression (LGR), decision tree (DT), random forest (RF), gradient boosting (GB), and eXtreme gradient boosting (XGB), to develop a two-stage ML algorithm-based prediction scheme and evaluate the important factors that predict CHD mortality. LGR served as a bench method. Regarding the validation and testing datasets from 1- and 3-year mortality prediction model, the RF had better accuracy and area-under-curve results among the five different ML methods. The stepwise RF model, which incorporates the most important factors of CHD mortality risk based on the average rank from DT, RF, GB, and XGB, exhibited superior predictive performance compared to LGR in predicting mortality among CHD patients over both 1-year and 3-year periods. We had developed a two-stage ML algorithm-based prediction scheme by implementing the stepwise RF that demonstrated satisfactory performance in predicting mortality in patients with CHD over 1- and 3-year periods. The findings of this study can offer valuable information to nephrologists, enhancing patient-centered decision-making and increasing awareness about risky laboratory data, particularly for patients with a high short-term mortality risk.

The association between plant and animal protein intake and quality of life in patients undergoing hemodialysis

Background

Hemodialysis (HD) patients often experience a significant reduction in quality of life (QOL). The source of dietary protein intake may influence the renal function and complications of HD patients. The present study assessed the relationship between plant and animal protein intake and QOL in HD patients.

Methods

264 adult patients under dialysis for at least three months were included in this cross-sectional study. Dietary intakes were collected using a valid and reliable 168-item semi-quantitative food frequency questionnaire (FFQ) over the past year. Total, animal, and plant proteins were calculated for each patient. To evaluate QOL, Kidney Disease Quality of Life Short Form (KDQOL-SF 1/3) was used. Anthropometric measures were assessed according to standard protocols.

Results

In this study, the average age of participants was 58.62 ± 15.26 years old; most (73.5%) were men. The mean of total, plant, and animal proteins intake were 66.40 ± 34.29 g/d, 34.60 ± 18.24 g/d, and 31.80 ± 22.21 g/d. Furthermore, the mean score of QOL was 59.29 ± 18.68. After adjustment for potential confounders, a significant positive association was found between total dietary protein intake and QOL (β = 0.12; p = 0.03). Moreover, there was a significant association between plant-based protein intake and QOL (β = 0.26; p < 0.001). However, the association between animal protein intake and QOL was insignificant (β = 0.03; p = 0.60).

Conclusion

Higher total and plant proteins intake were associated with better QOL in HD patients. Further studies, particularly prospective ones, are needed to corroborate these associations.

Physical function and physical activity in hemodialysis patients with peripheral artery disease

INTRODUCTION

Peripheral artery disease (PAD) is commonly observed in patients undergoing hemodialysis. PAD impairs the vasculature and leads to pathophysiologic changes in the skeletal muscles, causing physical function impairment and physical inactivity in general. However, it is unclear whether PAD adversely affects physical function and physical activity in patients on hemodialysis.

METHODS

We performed a cross-sectional study with a retrospective review of the data to determine whether PAD is associated with impaired physical function and physical activity in patients undergoing hemodialysis. The study population comprised 310 patients and 88 healthy subjects. PAD was diagnosed based on an ankle-brachial index of <1.00 in patients on hemodialysis. Measurements of physical function included maximum walking speed, muscle strength in the lower extremities, and balance while standing.

FINDINGS

Of the 310 patients, 84 (27.1%) had PAD. When patients undergoing hemodialysis were divided into those without PAD and those with PAD, both groups had poorer physical function and physical activity than the healthy control subjects. After adjustments for potential confounders, it was found that patients on hemodialysis with PAD had slower walking speed, poorer standing balance, and less physical activity than those without PAD. However, there was no significant difference in lower extremity muscle strength between the two groups.

DISCUSSION

PAD diagnosed based on an ankle-brachial index of <1.00 was independently associated with impaired physical function and reduced physical activity in patients undergoing hemodialysis.

Nocturnal Hemodialysis Leads to Improvement in Physical Performance in Comparison with Conventional Hemodialysis

End-stage kidney disease patients treated with conventional hemodialysis (CHD) are known to have impaired physical performance and protein-energy wasting (PEW). Nocturnal hemodialysis (NHD) was shown to improve clinical outcomes, but the evidence is limited on physical performance and PEW. We investigate whether NHD improves physical performance and PEW. This prospective, multicenter, non-randomized cohort study compared patients who changed from CHD (2−4 times/week 3−5 h) to NHD (2−3 times/week 7−8 h), with patients who continued CHD. The primary outcome was physical performance at 3, 6 and 12 months, assessed with the short physical performance battery (SPPB). Secondary outcomes were a 6-minute walk test (6MWT), physical activity monitor, handgrip muscle strength, KDQOL-SF physical component score (PCS) and LAPAQ physical activity questionnaire. PEW was assessed with a dietary record, dual-energy X-ray absorptiometry, bioelectrical impedance spectroscopy and subjective global assessment (SGA). Linear mixed models were used to analyze the differences between groups. This study included 33 patients on CHD and 32 who converted to NHD (mean age 55 ± 15.3). No significant difference was found in the SPPB after 1-year of NHD compared to CHD (+0.24, [95% confidence interval −0.51 to 0.99], p = 0.53). Scores of 6MWT, PCS and SGA improved (+54.3 [95%CI 7.78 to 100.8], p = 0.02; +5.61 [−0.51 to 10.7], p = 0.03; +0.71 [0.36 to 1.05], p < 0.001; resp.) in NHD patients, no changes were found in other parameters. We conclude that NHD patients did not experience an improved SPPB score compared to CHD patients; they did obtain an improved walking distance and self-reported PCS as well as SGA after 1-year of NHD, which might be related to the younger age of these patients.

Study protocol and baseline characteristics of newly induced dialysis patients: a prospective multi-center cohort study with a biological sample bank, the Ibaraki Dialysis Initiation Cohort (iDIC) study

Background

Patients with end-stage kidney disease (ESKD) face higher risks of life-threatening events including cardiovascular disease. Various risk factors are identified as agents influencing the life prognosis of ESKD patients. Herein, we evaluated the risk factors related to the outcomes of Japanese patients with dialysis induction. We present the study protocol, the patients’ baseline characteristics, and their outcomes.

Methods

The Ibaraki Dialysis Initiation Cohort (iDIC) Study is a prospective multi-center cohort study in collaboration with 60 tertiary-care facilities in Ibaraki Prefecture, Japan. We collected baseline data from clinical records and analyzed blood and urine samples of these facilities’ patients with diabetic nephropathy, hypertensive nephrosclerosis, and chronic glomerulonephritis (CGN). The study’s primary outcome was the survival rate at 24 months after dialysis induction. We performed a Kaplan-Meier analysis for cumulative survival and a Cox proportional hazards analysis for all-cause mortality and hospitalization.

Results

We analyzed 636 patients’ cases (424 males, 212 females, age 67.4 ± 13.1 yrs. [mean ± SD]). We compared the patients’ baseline data with those of similar cohort studies. As the primary kidney disease, 327 cases (51.4%) were diagnosed as diabetic nephropathy, 101 (15.9%) as hypertensive nephrosclerosis, and 114 (17.9%) as CGN. The mean serum creatinine value was 9.1 ± 2.9 mg/dL. The mean estimated glomerular filtration rate was 5.6 ± 1.8 mL/min/1.73m². The cumulative survival rates at 6 months and 24 months after dialysis induction were 95.2 and 87.7%, respectively. The cumulative survival rate was significantly lower with increasing age. A Cox proportional hazards regression analysis demonstrated that high age was significantly associated with all-cause mortality.

Conclusions

Regarding the clinical characteristics of these newly induced dialysis patients, the same trend as in other cohort studies was observed. Another study is underway to explore prognostic factors based on the iDIC Study’s findings.

Changes in practice patterns in Japan from before to after JSDT 2013 guidelines on hemodialysis prescriptions: results from the JDOPPS

BACKGROUND

The Japanese Society for Dialysis Therapy (JSDT) published in 2013 inaugural hemodialysis (HD) guidelines. Specific targets include 1.4 for single-pool Kt/V (spKt/V) with a minimum dose of 1.2, minimum dialysis session length of 4 hours, minimum blood flow rate (BFR) of 200 mL/min, fluid removal rate no more than 15 mL/kg/hr, and hemodiafiltration (HDF) therapy for certain identified symptoms. We evaluated the effect of these guidelines on actual practice in the years spanning 2005 - 2018.

METHODS

Analyses were carried out to describe trends in the above HD prescription practices from December 2005 to April 2013 (before guideline publication) to August 2018 based on prevalent patient cross-sections from approximately 60 randomly selected HD facilities participating in the Japan Dialysis Outcomes and Practice Patterns Study.

RESULTS

From April 2006 to August 2017 continual rises occurred in mean spKt/V (from 1.35 to 1.49), and percent of patients having spKt/V>1.2 (71% to 85%). Mean BFR increased with time from 198.3 mL/min (April 2006) to 218.4 mL/min (August 2017) , along with percent of patients with BFR >200 ml/min (65% to 85%). HDF use increased slightly from 6% (April 2006 and August 2009) to 8% by April 2013, but increased greatly thereafter to 23% by August 2017. In contrast, mean HD treatment time showed little change from 2006-2017, whereas mean UFR declined from 11.3 in 2006 to 8.4 mL/Kg/hour in 2017.

CONCLUSIONS

From 2006 - 2018 Japanese HD patients experienced marked improvement in reaching the spKt/V target specified by the 2013 JSDT guidelines. This may have been due to moderate increase in mean BFR even though mean HD session length did not change much. In addition, HDF use increased dramatically in this time period. Other HD delivery changes during this time, such as increased use of super high flux dialyzers, also merit study. While we cannot definitively conclude a causal relationship between the publication of the guidelines and the subsequent practice changes in Japan, those changes moved practice closer to the recommendations of the guidelines.

Does kidney transplantation with a standard or expanded criteria donor improve patient survival? Results from a Belgian cohort

BACKGROUND

Changes in recipient and donor factors have reopened the question of survival benefits of kidney transplantation versus dialysis.

METHODS

We analysed survival among 3808 adult Belgian patients waitlisted for a first deceased donor kidney transplant from 2000 to 2012. The primary outcome was mortality during the median waiting time plus 3 years of follow-up after transplantation or with continued dialysis. Outcomes were analysed separately for standard criteria donor (SCD) and expanded criteria donor (ECD) kidney transplants. We adjusted survival analyses for recipient age (20-44, 45-64 and ≥65 years), sex and diabetes as the primary renal disease.

RESULTS

Among patients ≥65 years of age, only SCD transplantation provided a significant survival benefit compared with dialysis, with a mortality of 16.3% [95% confidence interval (CI) 13.2-19.9] with SCD transplantation, 20.5% (95% CI 16.1-24.6) with ECD transplantation and 24.6% (95% CI 19.4-29.5) with continued dialysis. Relative mortality risk was increased in the first months after transplantation compared with dialysis, with equivalent risk levels reached earlier with SCD than ECD transplantation in all age groups.

CONCLUSIONS

The results of this study suggest that older patients might gain a survival benefit with SCD transplantation versus dialysis, but any survival benefit with ECD transplantation versus dialysis may be small.

[Kidney transplantation in the elderly: A benefit for all patients?]

Age per se should not be a contraindication to kidney transplantation. The first studies have shown a benefit for the survival of elderly eligible patients getting a kidney transplant compared to be maintained on the waiting list. However, more recent data suggest that this benefit is not as constant, notably with a significant early mortality period. The eligibility of elderly patients for transplantation must be based on the usual consideration of co-morbidities, but should also include, for some patients, a geriatric evaluation to detect clinical symptoms of frailty. The decision to transplant an elderly recipient must also integrate the characteristics of the donors, since the use of donors with increasingly expanding criteria can have a negative impact on the survival of these patients.

Transplantation in older individuals: is it really better than dialysis?

PURPOSE OF REVIEW

The kidney transplantation landscape has changed dramatically over the last 2 decades. First, transplantation is performed in patients previously considered ineligible for transplantation, including older patients and patients with multiple comorbidities. Second, organ shortages have increased the use of less-than-optimal donor kidneys, like organs from expanded criteria donors or donors after cardiac death. Third, improvements in managing chronic kidney disease and dialysis have improved survival on dialysis. Therefore, the question arises: does transplantation currently benefit older transplant candidates?

RECENT FINDINGS

The current review describes important changes in transplantation over the last 20 years. We review recent data on survival with dialysis versus transplantation in older individuals. Finally, we consider methodological issues that might influence conclusions drawn in current studies.

SUMMARY

Limited data are available to assess the potential survival benefit of kidney transplantations in older individuals. The available evidence suggests that transplantation might provide survival benefit in older individuals, even with aged kidney donors, but risks vary widely with donor quality and recipient health status. More research is needed to make adequate predictions of which donor kidneys might lead to good outcomes and which patient characteristics might define a good transplant candidate.

Sodium, volume and pressure control in haemodialysis patients for improved cardiovascular outcomes

Chronic volume overload is pervasive in patients on chronic haemodialysis and substantially increases the risk of cardiovascular death. The rediscovery of the three-compartment model in sodium metabolism revolutionizes our understanding of sodium (patho-)physiology and is an effect modifier that still needs to be understood in the context of hypertension and end-stage kidney disease. Assessment of fluid overload in haemodialysis patients is central yet difficult to achieve, because traditional clinical signs of volume overload lack sensitivity and specificity. The highest all-cause mortality risk may be found in haemodialysis patients presenting with high fluid overload but low blood pressure before haemodialysis treatment. The second highest risk may be found in patients with both high blood pressure and fluid overload, while high blood pressure but normal fluid overload may only relate to moderate risk. Optimization of fluid overload in haemodialysis patients should be guided by combining the traditional clinical evaluation with objective measurements such as bioimpedance spectroscopy in assessing the risk of fluid overload. To overcome the tide of extracellular fluid, the concept of time-averaged fluid overload during the interdialytic period has been established and requires possible readjustment of a negative target post-dialysis weight. ²³Na-magnetic resonance imaging studies will help to quantitate sodium accumulation and keep prescribed haemodialytic sodium mass balance on the radar. Cluster-randomization trials (e.g. on sodium removal) are underway to improve our therapeutic approach to cardioprotective haemodialysis management.

Frailty and the Kidney Transplant Wait List: Protocol for a Multicenter Prospective Study

Background:

Understanding how frailty affects patients listed for transplantation has been identified as a priority research need. Frailty may be associated with a high risk of death or wait-list withdrawal, but this has not been evaluated in a large multicenter cohort of Canadian wait-listed patients.

Objective:

The primary objective is to evaluate whether frailty is associated with death or permanent withdrawal from the transplant wait list. Secondary objectives include assessing whether frailty is associated with hospitalization, quality of life, and the probability of being accepted to the wait list.

Design:

Prospective cohort study.

Setting:

Seven sites with established renal transplant programs that evaluate patients for the kidney transplant wait list.

Patients:

Individuals who are being considered for the kidney transplant wait list.

Measurements:

We will assess frailty using the Fried Phenotype, a frailty index, the Short Physical Performance Battery, and the Clinical Frailty Scale at the time of listing for transplantation. We will also assess frailty at the time of referral to the wait list and annually after listing in a subgroup of patients.

Methods:

The primary outcome of the composite of time to death or permanent wait-list withdrawal will be compared between patients who are frail and those who are not frail and will account for the competing risks of deceased and live donor transplantation. Secondary outcomes will include number of hospitalizations and length of stay, and in a subset, changes in frailty severity over time, change in quality of life, and the probability of being listed. Recruitment of 1165 patients will provide >80% power to identify a relative hazard of ≥1.7 comparing patients who are frail to those who are not frail for the primary outcome (2-sided α = .05), whereas a more conservative recruitment target of 624 patients will provide >80% power to identify a relative hazard of ≥2.0.

Results:

Through December 2019, 665 assessments of frailty (inclusive of those for the primary outcome and all secondary outcomes including repeated measures) have been completed.

Limitations:

There may be variation across sites in the processes of referral and listing for transplantation that will require consideration in the analysis and results.

Conclusions:

This study will provide a detailed understanding of the association between frailty and outcomes for wait-listed patients. Understanding this association is necessary before routinely measuring frailty as part of the wait-list eligibility assessment and prior to ascertaining the need for interventions that may modify frailty.

Trial Registration:

Not applicable as this is a protocol for a prospective observational study.

A Joint Evaluation of Impaired Cardiac Sympathetic Responses and Malnutrition-Inflammation Cachexia for Mortality Risks in Hemodialysis Patients

Background: Cardiac sympathetic response (CSR) and malnutrition-inflammation syndrome (MIS) score are validated assessment tools for patients' health condition. We aim to evaluate the joint effect of CSR and MIS on all-cause and cardiovascular (CV) mortality in patients with hemodialysis (HD).

Methods: Changes in normalized low frequency (ΔnLF) during HD were utilized for quantification of CSR. Unadjusted and adjusted hazard ratios (aHRs) of mortality risks were analyzed in different groups of ΔnLF and MIS score.

Results: In multivariate analysis, higher ΔnLF was related to all-cause, CV and sudden cardiac deaths [aHR: 0.78 (95% confidence interval (CI): 0.72–0.85), 0.78 (95% CI: 0.70–0.87), and 0.74 (95% CI: 0.63–0.87), respectively]. Higher MIS score was associated with incremental risks of all-cause, CV and sudden cardiac deaths [aHR: 1.36 (95% CI: 1.13–1.63), 1.33 (95% CI: 1.06 – 1.38), and 1.50 (95% CI: 1.07–2.11), respectively]. Patients with combined lower ΔnLF (≤6.8 nu) and higher MIS score were at the greatest risk of all-cause and CV mortality [aHR: 5.64 (95% CI: 1.14–18.09) and 5.86 (95% CI: 1.64–13.65), respectively].

Conclusion: Our data indicate a joint evaluation of CSR and MIS score to identify patients at high risk of death is more comprehensive and convincing. Considering the extremely high prevalence of cardiac autonomic neuropathy and malnutrition-inflammation cachexia in HD population, a non-invasive monitoring system composed of CSR analyzer and MIS score calculator should be developed in the artificial intelligence-based prediction of clinical events.

Perioperative outcomes and risk assessment in dialysis patients: current knowledge and future directions

Perioperative medicine is rapidly emerging as a key discipline to address the specific needs of high-risk surgical groups, such as those on chronic dialysis. Crude hospital separation rates for chronic dialysis patients are considerably higher than patients with normal renal function, with up to 15% of admission being related to surgical intervention. Dialysis dependency carries substantial mortality and morbidity risk compared to patients with normal renal function. This group of patients has a high comorbid burden and complex medical need, making accurate perioperative planning essential. Existing perioperative risk assessment tools are unvalidated in chronic dialysis patients. Furthermore, they fail to incorporate important dialysis treatment-related characteristics that could potentially influence perioperative outcomes. There is a dearth of information on perioperative outcomes of Australasian dialysis patients. Current perioperative outcome estimates stem predominantly from North American literature; however, the generalisability of these findings is limited, as the survival of North American dialysis patients is significantly inferior to their Australasian counterparts and potentially confounds reported perioperative outcomes; let alone regional variation in surgical indication and technique. We propose that data linkage between high-quality national registries will provide more complete data with more detailed patient and procedural information to allow for more informative analyses to develop and validate dialysis-specific risk assessment tools.

High sensitivity Troponin-I levels in asymptomatic hemodialysis patients

Reduction in renal clearance and removal by hemodialysis adversely affect the level and utility of high-sensitivity troponin I (hsTnI) for diagnosis of acute myocardial infarction (AMI) in hemodialysis (HD) patients. Furthermore, HD process itself might cause undesirable myocardial injury and enhance post HD hsTnI levels. This comparative cross-sectional study was conducted to compare the hsTnI levels between 100 asymptomatic HD patients and their 107 matched non-chronic kidney disease (CKD) population. The hsTnI levels in HD group were higher than non-CKD group [median (IQR): 54.3 (20.6-152.7) vs. 18 (6.2-66.1) ng/L, p < .001)]. The hsTnI levels reduced after HD process from 54.3 (20.6-152.7) ng/L in pre-HD to 27.1 (12.3-91.4) ng/L in post-HD (p = .015). Of interest, 25% of HD patients had increment of hsTnI after HD and might represent HD-induced myocardial injury. The significant risk factors were high hemoglobin level and high blood flow rate. In conclusion, the baseline hsTnI levels in asymptomatic HD patients were higher than non-CKD population. The dynamic change of hsTnI over time would be essential for the diagnosis of AMI. Certain numbers of asymptomatic HD patients had HD-induced silent myocardial injury and should be aggressively investigated to prevent further cardiovascular mortality.

Protein C and protein S deficiencies may be related to survival among hemodialysis patients

Background

Thrombophilia due to protein C (PC) and protein S (PS) deficiencies is highly prevalent among patients with stage 5 chronic kidney disease and is reported to arise due to extracorporeal circulation during hemodialysis (HD). This study aimed to evaluate the relationship between HD treatment and thrombophilia.

Methods

A total of 114 Japanese patients on maintenance HD (62 men, 52 women) were followed during 2008–2011. Their survival rates were compared against the duration of HD. Prior to each HD, coagulation/fibrinolysis parameters and PC and PS activities were measured using standard techniques. The patients were divided into two groups: Group 1, with PC and/or PS deficiencies (n = 32), and Group 2, without PC and PS deficiencies (n = 82). The influence of such deficiencies and duration of dialysis on survival was examined. Time-to-event analysis was applied using Kaplan-Meier estimates, and the log-rank test was proposed to test the equivalence of relative survival data. Hazard ratios and 95% confidence intervals (CI) were calculated.

Results

Of the 114 patients, 37 died (Group 1, 22; Group 2, 15). The hazard ratio (95% CI) was higher (p = 0.004) in Group 1 than Group 2. Gene analyses of PC and PS were performed in 14 patients from Group 1. No mutations in either protein were observed. We analyzed the causes of death in both groups; however, the estimated thrombophilia-related incidence of death could not be determined due to small sample size of HD patients.

Conclusions

Our results suggest that PC and PS deficiencies may be related to survival in HD patients. However, this finding warrants additional research.

Detecting high-risk chronic kidney disease-mineral bone disorder phenotypes among patients on dialysis: a historical cohort study

BACKGROUND

The clinical management of chronic kidney disease-mineral bone disorder (CKD-MBD) remains extremely challenging, partially due to difficulties in defining high-risk phenotypes based on serum biomarkers. We evaluated the prevalence and outcomes of 27 mutually exclusive CKD-MBD phenotypes in a large, multi-national cohort of chronic dialysis patients over a 5-year follow-up study.

METHODS

In this historical cohort study, we enrolled all haemodialysis patients registered in EuCliD® on 1 July 2011 across 28 Europe, the Middle East and Africa (EMEA) and South American countries. We created 27 mutually exclusive phenotypes based on combinations of serum parathyroid hormone (PTH), phosphorus (P) and calcium (Ca) 6-month averages (L, low; T, target; H, high). We tested the association between CKD-MBD phenotypes and 5-year mortality and hospitalization risk by outcome risk score-adjusted proportional hazard regression.

RESULTS

We enrolled 35 721 eligible patients. Eastern European and South American countries generally achieved poorer CKD-MBD control when compared with Western European countries (prevalence ratio: 0.79; P < 0.001). There were 15 795 deaths [126.7 deaths/1000 person-years; 95% confidence interval (CI) 124.7-128.7]; 18 014 had at least one hospitalization (203.9 hospitalizations/1000 person-years; 95% CI 201.0-206.9); the incidence of the composite endpoint was 280.0 events/1000 person-years (95% CI 276.6-283.5). In the fully adjusted model, relative mortality risk ranged from hazard ratio (HR) = 1.07 (PTH/Ca/P: TLT) to HR = 1.59 (PTH/Ca/P: LTL), whereas the relative composite endpoint risk ranged from HR = 1.07 (PTH/Ca/P: TTH) to HR = 1.36 (PTH/Ca/P: LTL).

CONCLUSION

We identified several CKD-MBD phenotypes associated with reduced hospitalization-free survival and increased mortality. Ranking of relative risk estimates or excess events concurs in informing healthcare priority setting.

Living Kidney Donation Is Recipient Age Sensitive and Has a High Rate of Donor Organ Disqualifications

BACKGROUND

Living donor kidney transplantation (LDKT) is the best therapy for patients with chronic renal failure. Its advantages, compared with cadaveric transplantation, include the possibility of avoiding dialysis, the likelihood of best outcome, and donor pool expansion. Careful assessment of potential donors is important to minimize the risks and ensure success. However, the proportion of donors disqualified has been poorly investigated. The aim of this work is to describe our experience and present the main reasons for missed donation.

METHODS

This was a single-center, retrospective study of all potential donors and recipients evaluated for LDKT between January 2008 and December 2017.

RESULTS

During the period of study, 81 donor-recipient pairs were evaluated. Of these, 45.7% were disqualified and 37 LDKTs were carried out. LDKT was the first choice in 68% of cases and preemptive in 20%; 60% of transplants were among family members. Sex distribution revealed a prevalence of females in the donor group (69%) and males in the recipient group (70%). The mean living donor age was 53 ± 9.5 years; the mean recipient age was lower in recipients listed in the living transplant program than those listed for cadaver transplantation (45.8 ± 13.4 vs 54.2 ± 11.08; P < .0001). Reasons for denial included hypertension (18.9%), deceased donor transplant performed during the study period (16.2%), urologic pathology (13.5%), incompatibility (13.5%), withdrawal of consent by donor or recipient (13.5%), psychological unsuitability (8.1%), donor cancer (5.4%), and reduced renal clearance (2.7%).

CONCLUSION

LDKT is considered an option especially for younger recipients. Of the potential kidney living donors, 45.7% were disqualified during the evaluation, with medical reasons being the primary cause.

Dipstick proteinuria and all-cause mortality among the general population

BACKGROUND

Dipstick proteinuria, but not albuminuria, is used for general health screening in Japan. How the results of dipstick proteinuria tests correlate with mortality and, however, is not known.

METHODS

Subjects were participants of the 2008 Tokutei-Kenshin (Specific Health Check and Guidance program) in six districts in Japan. On the basis of the national database of death certificates from 2008 to 2012, we used a personal identifier in two computer registries to identify participants who might have died. The hazard ratio (95% confidence interval, CI) was calculated by Cox-proportional hazard analysis.

RESULTS

Among a total of 140,761 subjects, we identified 1641 mortalities that occurred by the end of 2012. The crude mortality rates were 1.1% for subjects who were proteinuria (-), 1.5% for those with proteinuria (+/-), 2.0% for those with proteinuria (1+), 3.5% for those with proteinuria (2+), and 3.7% for those with proteinuria (≥ 3+). After adjusting for sex, age, body mass index, estimated glomerular filtration rate, comorbid condition, past history, and lifestyle, the hazard ratio (95% CI) for dipstick proteinuria was 1.262 (1.079-1.467) for those with proteinuria (+/-), 1.437 (1.168-1.748) for those with proteinuria (1+), 2.201 (1.688-2.867) for those with proteinuria (2+), and 2.222 (1.418-3.301) for those with proteinuria (≥ 3+) compared with the reference of proteinuria (-).

CONCLUSION

Dipstick proteinuria is an independent predictor of death among Japanese community-based screening participants.

Dialysis Case Volume Associated With In-Hospital Mortality in Maintenance Dialysis Patients

Introduction

Accumulating evidence suggests that a large hospital volume (HV) is associated with favorable outcomes in various diseases or surgical procedures. The aim of this study is to clarify the correlation of HV and dialysis case volume (DCV) with in-hospital death in patients on maintenance dialysis.

Methods

The study cohort was derived from the Diagnosis Procedure Combination database, a national inpatient database in Japan, from 2012 to 2014. We included 382,689 admissions of maintenance dialysis patients over the age of 20 years in the analysis. HV was defined as the mean number of daily hospitalized patients, and DCV was defined as the mean number of annually hospitalized patients on maintenance dialysis. The primary outcome was in-hospital all-cause mortality, evaluated using multivariable logistic regression models across the respective quartiles of HV and DCV.

Results

The mean age of participants was 69 ± 12 years; 94% were receiving hemodialysis, and 21,182 patients (5.5%) died after hospitalization. In unadjusted models, larger HV and DCV were both associated with lower in-hospital mortality. However, this association remained significant only for DCV after adjustment for potential confounders, with multivariable-adjusted odds ratios of 0.82 (95% confidence interval [CI], 0.79–0.85), 0.76 (95% CI, 0.73–0.80), and 0.68 (95% CI, 0.65–0.72) for DCV 249 to 432, 433 to 713, and ≥714 (vs. ≤ 248) admissions per year, respectively. Multivariable subgroup analyses determined that this association was independent of age, sex, dialysis modality, Charlson Comorbidity Index, and emergency admission.

Conclusion

Selective admission to hospitals with a large DCV may improve outcomes of dialysis patients.

Impact of end-stage renal disease on hospital outcomes among patients admitted to intensive care units: A retrospective matched-pair cohort study

AIM

We aimed to estimate the burden of end-stage renal disease (ESRD) among patients admitted to intensive care units (ICUs), by comparing hospital outcomes between patients with and without ESRD.

METHODS

Using the Japanese Diagnosis Procedure Combination database, we identified patients aged 20 years or older who were admitted to ICUs for ≥3 days (2 nights) in 2011. We created a matched cohort of patients with and without ESRD for hospital, age, sex, main diagnosis category, and ICU admission type (medical or surgical) at a maximum ratio of 1:3. For these matched patients, we compared patient characteristics, treatment regimens at ICU admission, and hospital outcomes. We also performed a multivariable logistic regression analysis for the associations between ESRD and 28-day (counting from ICU admission) and in-hospital mortality.

RESULTS

Among the 164 423 eligible patients, 7998 (4.9%) had ESRD, from which 5228 ESRD and 12 274 non-ESRD patients were matched for the aforementioned factors. Compared to non-ESRD patients, ESRD patients were on more intensive treatment regimens, including mechanical ventilation, vasoactive drugs, and blood transfusion. Patients with ESRD showed significantly higher ICU, 28-day, and in-hospital mortality and longer lengths of stay in the ICU and hospital (28-day mortality: 11.7% vs. 8.3%; P < 0.001, in-hospital mortality: 21.1% vs. 12.0%; P < 0.001). After adjusting for confounding factors, ESRD was independently associated with 28-day mortality (adjusted odds ratio: 1.36, 95% confidence interval [CI]: 1.22-1.52) and in-hospital mortality (adjusted odds ratio: 1.85, 95% CI: 1.69-2.02).

CONCLUSION

This study involving the Japanese national inpatient database, with a matched-pair cohort design, suggested that ESRD is an important burden in the critical care setting.

Long-Term Therapy Outcomes When Treating Chronic Kidney Disease Patients with Paricalcitol in German and Austrian Clinical Practice (TOP Study)

Paricalcitol is approved for prevention and therapy of secondary hyperparathyroidism (sHPT) in patients with chronic kidney disease (CKD), with only short-term data in clinical routine settings. A 12-month observational study was conducted in Germany and Austria (90 centers, 761 patients) from 2008 to 2013. Laboratory values, demographical, and clinical data were documented in 629 dialysis patients and 119 predialysis patients. In predialysis patients, median intact parathormone (iPTH) was 180.0 pg/mL (n = 105) at the start of the study, 115.7 pg/mL (n = 105) at last documentation, and 151.8 pg/mL (n = 50) at month 12, with 32.4% of the last documented iPTH values in the KDOQI (Kidney Disease Outcomes Quality Initiative) target range. In dialysis patients, median iPTH was 425.5 pg/mL (n = 569) at study start, 262.3 pg/mL (n = 569) at last documentation, and 266.1 pg/mL (n = 318) at month 12, with 36.5% of dialysis patients in the KDOQI target range. Intravenous paricalcitol showed more homogenous iPTH control than oral treatment. Combined analysis of all dialysis patients indicated comparable and stable mean serum calcium and phosphate levels throughout the study. Clinical symptoms, such as itching, bone pain, and fatigue, were improved compared with study entry. The spectrum and frequency of adverse events mirrored the known pattern for patients on dialysis. Paricalcitol is efficacious and has a consistent safety profile in sHPT over 12 months.

Associations Between Low Serum Testosterone and All-Cause Mortality and Infection-Related Hospitalization in Male Hemodialysis Patients: A Prospective Cohort Study

Introduction

Infectious diseases are the second highest cause of death in patients on dialysis. In addition, testosterone deficiency or hypogonadism is prevalent in dialysis patients. However, to our knowledge, no studies have investigated the association between testosterone levels and infectious events. We aimed to evaluate whether serum testosterone levels are associated with infection-related hospitalization in male hemodialysis patients in a prospective cohort study.

Methods

We divided the study population into 3 groups based on serum testosterone levels. Associations between testosterone levels and clinical outcomes of infection-related hospitalization, all-cause mortality, and cardiovascular disease (CVD) events were analyzed using the Cox proportional hazard model.

Results

Nine hundred two male patients were enrolled and followed up for a median of 24.7 months. Their mean ± SD age was 63.4 ± 11.8 years, and their median (interquartile range) of total testosterone was 11.7 nmol/l (7.9–14.9 nmol/l). During follow-up, 123 participants died. Infection-related hospitalization and CVD events occurred in 116 and 151 patients, respectively. Infection-related hospitalization was more frequent in the lower testosterone tertile than in the higher testosterone tertile (hazard ratio [HR]: 2.12; 95% confidence interval [CI]: 1.18–3.79; P = 0.01) in adjusted models. Moreover, all-cause mortality was significantly greater in the lower testosterone tertile than in the higher testosterone tertile in adjusted analysis (HR: 2.26; 95% CI: 1.21–4.23; P = 0.01). In contrast, there were no significant differences in CVD events by testosterone level.

Discussion

Low levels of testosterone may be associated with higher rates of infection-related hospitalization and all-cause mortality in male hemodialysis patients.

Coronary Artery Bypass Surgery in End-Stage Renal Disease Patients

The number of patients requiring hemodialysis is continuously increasing around the world. Hemodialysis affects patient quality of life and it is also associated with a higher risk for cardiovascular events. In addition to traditional risk factors for cardiovascular events such as hypertension, hyperlipidemia, and diabetes, hemodialysis is associated with hyperphosphatemia, chronic inflammation, vascular calcification, and anemia which accelerate atherosclerosis, vascular stiffness, and cardiac ischemia. Treatment strategy for coronary revascularization in this progressive disease remains controversial. However, a systematic treatment including medical therapy and complete revascularization through a less invasive strategy should be considered in addressing this problem. This review discusses the epidemiology, vascular pathology and current treatment options in patients with end-stage renal disease requiring coronary revascularization.

Physical performance and protein-energy wasting in patients treated with nocturnal haemodialysis compared to conventional haemodialysis: protocol of the DiapriFIT study

BACKGROUND

Poor physical performance and protein-energy wasting (PEW) are health issues of major concern in haemodialysis patients. The conventional haemodialysis (CHD) regime, three times per week 3-5 h, is subject of discussion because of high morbidity and mortality rates. When patients switch from CHD to longer dialysis sessions, i.e. nocturnal haemodialysis (NHD), improvement in protein intake and increase in body weight is seen. However, it is unclear whether physical performance and more important aspects of PEW, such as body composition, improve as well. Therefore, the aim of this study is to investigate whether physical performance improves and PEW decreases, when patients switch from CHD to NHD. A second aim is to assess the influence of NHD on the biomarkers fibroblast growth factor-23 and sclerostin which are thought to be associated with malnutrition and mortality in patients on haemodialysis.

METHODS

This study is a prospective multicentre cohort study with an inclusion aim of 50 patients: 25 patients in a control group (three times per week, 3-5 h CHD) and 25 patients in a nocturnal group (three times per week, 7-9 h NHD). Primary outcome is change in physical performance, measured by the Short Physical Performance Battery. Additional measurements are a 6-min walk test, handgrip strength, a physical activity questionnaire and physical activity monitoring. The secondary outcome of the study is PEW, which will be evaluated by body weight, dual-energy X-ray absorptiometry, bio-electrical impedance spectroscopy, mid-upper arm muscle circumference, subjective global assessment, visual analogue scale for appetite and dietary records. Laboratory measurements including fibroblast growth factor-23 and sclerostin, and quality of life assessed with the Kidney Disease Quality of Life-Short Form are also studied. In every patient, four repeated measurements will be performed during one year of follow-up.

DISCUSSION

This study will investigate whether physical performance improves and PEW decreases when patients switch from CHD to NHD, compared to a control group who continue treatment with CHD. Strengths of this study are the comparison with a conventional haemodialysis cohort, and the broad variety of objective measurements combined with patient-reported outcomes of physical performance and PEW.

TRIAL REGISTRATION

NTR4715 , Netherlands Trial Register. Registered 30 July 2014.

Development of a new risk model for predicting cardiovascular events among hemodialysis patients: Population-based hemodialysis patients from the Japan Dialysis Outcome and Practice Patterns Study (J-DOPPS)

Background

Cardiovascular (CV) events are the primary cause of death and becoming bedridden among hemodialysis (HD) patients. The Framingham risk score (FRS) is useful for predicting incidence of CV events in the general population, but is considerd to be unsuitable for the prediction of the incidence of CV events in HD patients, given their characteristics due to atypical relationships between conventional risk factors and outcomes. We therefore aimed to develop a new prognostic prediction model for prevention and early detection of CV events among hemodialysis patients.

Methods

We enrolled 3,601 maintenance HD patients based on their data from the Japan Dialysis Outcomes and Practice Patterns Study (J-DOPPS), phases 3 and 4. We longitudinaly assessed the association between several potential candidate predictors and composite CV events in the year after study initiation. Potential candidate predictors included the component factors of FRS and other HD-specific risk factors. We used multivariable logistic regression with backward stepwise selection to develop our new prediction model and generated a calibration plot. Additinially, we performed bootstrapping to assess the internal validity.

Results

We observed 328 composite CV events during 1-year follow-up. The final prediction model contained six variables: age, diabetes status, history of CV events, dialysis time per session, and serum phosphorus and albumin levels. The new model showed significantly better discrimination than the FRS, in both men (c-statistics: 0.76 for new model, 0.64 for FRS) and women (c-statistics: 0.77 for new model, 0.60 for FRS). Additionally, we confirmed the consistency between the observed results and predicted results using the calibration plot. Further, we found similar discrimination and calibration to the derivation model in the bootstrapping cohort.

Conclusions

We developed a new risk model consisting of only six predictors. Our new model predicted CV events more accurately than the FRS.

Does wealth make health? Cherchez la renal replacement therapy

In this issue of CKJ, McQuarrie et al. have explored the relationship between socioeconomic status and outcomes among Scottish patients with a renal biopsy diagnosis of primary glomerulonephritis. Patients in the lower socioeconomic category had a twofold higher risk of death. No significant differences were observed on progression to end-stage renal disease (ESRD) requiring renal replacement therapy (RRT), suggesting that overall medical management was appropriate for all socioeconomic categories. The findings are significant since they come from an ethnically homogeneous population with free access to healthcare; they also relate to a specific aetiology of chronic kidney disease (CKD) expected to be less dependent on unhealthy lifestyles than other more frequent aetiologies that dominate studies of CKD in general, such as diabetic or hypertensive nephropathy. A closer look at the data suggests that living in a high socioeconomic area is associated with lower mortality, rather than the other way round. Furthermore, the differences in mortality were most pronounced during the RRT stage of CKD, providing clues for further research. In this regard, Wilmink et al. and Nee et al. point to access to pre-ESRD nephrology care and to the best kidney transplantation options as modifiable factors to be studied in the realm of T3 translational research to improve CKD patient outcomes.

Standardized Prevalence Ratios for Atrial Fibrillation in Adult Dialysis Patients in Japan

Background

While it is assumed that dialysis patients in Japan have a higher prevalence of atrial fibrillation (AF) than the general population, the magnitude of this difference is not known.

Methods

Standardized prevalence ratios (SPRs) for AF in dialysis patients (n = 1510) were calculated compared to data from the general population (n = 26 454) living in the same area.

Results

The prevalences of AF were 3.8% and 1.6% in dialysis patients and the general population, respectively. In male subjects, these respective values were 4.9% and 3.3%, and in female subjects they were 1.6% and 0.6%. The SPRs for AF were 2.53 (95% confidence interval [CI], 1.88–3.19) in all dialysis patients, 1.80 (95% CI, 1.30–2.29) in male dialysis patients, and 2.13 (95% CI, 0.66–3.61) in female dialysis patients.

Conclusions

The prevalence of AF in dialysis patients was twice that in the population-based controls. Since AF strongly contributes to a higher risk of cardiovascular mortality and morbidity in the general population, further longitudinal studies should be conducted regarding the risk of several outcomes attributable to AF among Japanese dialysis patients.

Incidence and prevalence of hepatitis B and hepatitis C viruses in hemodialysis patients in Lebanon

AIM: To determine the incidence and the prevalence of hepatitis B and C viral infections in patients on hemodialysis (HD) across Lebanon.

METHODS: We reviewed the data registry at the Lebanese Ministry of Public Health where records of monthly hepatitis B surface antigen (HBsAg) and hepatitis C virus (HCV) serology are reported from 60 affiliated HD centers across Lebanon. All patients who were on HD or who started HD between October 2010 and July 2012 were included in the study. Patients from seven HD centers were excluded due to inadequate and incomplete results reporting. During the selected period, HBsAg and HCV serology were available for 3769 patients from 53 HD centers distributed at all Lebanese governorates. The prevalence was calculated by dividing the number of patients with positive HBsAg or HCV serology to the total number of patients. The Incidence was calculated by dividing the number of newly acquired infection to number of patients-years (p-y). Incidence rates at different governorates were compared to each other using two tailed Z test and a P value of < 0.05 was considered significant.

RESULTS: Sixty out of 3769 HD patients were found to have positive HBS Ag and 177 out of 3769 were positive for HCV Antibodies. The prevalence of hepatitis B virus (HBV) and HCV in HD patients across Lebanon was 1.6%, and 4.7%, respectively. The comparison of prevalence according to geographic distribution could not be done accurately due to the frequent shift of patients between dialysis centers at different governorates. The incidence rate was 0.27 per 100 p-y for HBV and 0.37 per 100 p-y for HCV. There was no significant difference concerning the incidence of HBV between HD centers at different governorates (all P values > 0.1), but this difference was highly significant concerning the incidence rates of HCV which occurred predominantly in the southern centers (1.47 per 100 p-y) with a P value of 0.00068 and 0.00374 when compared to Mount Lebanon (0.21 per 100 p-y) and the Northern centers (0.19 per 100 p-y), respectively.

CONCLUSION: The incidence rate of HBV and HCV is very low in the Lebanese HD centers and their prevalence is decreasing over the last two decades.

Effect of Blood Cadmium Level on Mortality in Patients Undergoing Maintenance Hemodialysis

Previous studies of general populations indicated environmental exposure to low-level cadmium increases mortality. However, the effect of cadmium exposure on maintenance hemodialysis (MHD) patients is unclear.A total of 937 MHD patients from 3 centers in Taiwan were enrolled in this 36-month observational study. Patients were stratified by baseline blood cadmium level (BCL) into 3 groups: high BCL (>0.521 μg/L; n = 312), intermediate BCL (0.286-0.521 μg/L; n = 313), and low BCL (<0.286 μg/L; n = 312). The mortality rates and causes of death were analyzed.The analytic results demonstrated patients in the high BCL group had a significantly higher prevalence of malnutrition and inflammation than patients in the low and intermediate BCL groups. After 3 years of follow-up, 164 (17.5%) patients died and the major cause of death was cardiovascular disease. A Cox multivariate analysis indicated the high BCL group had increased hazard ratios (HRs) for all-cause mortality (HR = 1.72; 95% confidence interval [CI]: 1.14-2.63; P = 0.018), cardiovascular-related mortality (HR = 1.85; 95% CI: 1.09-3.23; P = 0.032), and infection-related mortality (HR = 2.27; 95% CI: 1.12-4.55; P = 0.035). A Cox multivariate analysis of MHD patients who never smoked (n = 767) indicated the high BCL group had increased HRs for all-cause mortality (HR = 1.67; 95% CI: 1.04-2.63; P = 0.048) and cardiovascular-related mortality (HR = 2.08; 95% CI: 1.08-4.00; P = 0.044).In conclusion, BCL is an important determinant of mortality in MHD patients. Therefore, MHD patients should avoid cadmium exposure as much as possible, such as tobacco smoking and eating cadmium-containing foods.

Pro and con arguments in using alternative dialysis regimens in the frail and elderly patients

In the last decade, an increasing number of patients over 75 years of age are starting renal replacement therapy. Frailty is highly prevalent in elderly patients with end-stage renal disease (ESRD) in the context of the increased prevalence of some ESRD-associated conditions: protein-energy wasting, inflammation, anaemia, acidosis or hormonal disturbances. There are currently no hard data to support guidance on the optimal duration of dialysis for frail/elderly ESRD patients. The current debate is not about starting dialysis or managing conservatory frail ESRD patients, but whether a more intensive regimen once dialysis is initiated (for whatever reasons and circumstances) would improve patients' outcome. The most important issue is that all studies performed with extended/alternative dialysis regimens do not specifically address this particular type of patients and therefore all the inferences are derived from the general ESRD population. Care planning should be responsive to end-of-life needs whatever the treatment modality. Care in this setting should focus on symptom control and quality of life rather than life extension. We conclude that, similar to the general dialysed population, extensive application of more intensive dialysis schedules is not based on solid evidence. However, after a thorough clinical evaluation, a limited period of a trial of intensive dialysis could be prescribed in more problematic patients.

Impact of protein energy wasting status on survival among Afro-Caribbean hemodialysis patients: a 3-year prospective study

Background

We assessed the prognostic value of protein-energy wasting (PEW) on mortality in Afro-Caribbean MHD patients and analysed how diabetes, cardiovascular disease (CVD) and inflammation modified the predictive power of a severe wasting state.

Method

A 3-year prospective study was conducted in 216 patients from December 2011. We used four criteria from the nomenclature for PEW proposed by the International Society of Renal Nutrition and Metabolism in 2008: serum albumin 38 g/L, body mass index (BMI) ≤23 kg/m², serum creatinine ≤818 µmol/L and protein intake assessed by nPCR ≤0.8 g/kg/day. PEW status was categorized according the number of criteria. Cox regression analyses were used.

Results

Forty deaths (18.5 %) occurred, 97.5 % with a CV cause. Deaths were distributed as follows: 7.4 % in normal nutritional status, 13.2 % in slight wasting (1 PEW criterion), 28 % in moderate wasting (2 criteria) and 50 % in severe wasting (3–4 criteria). Among the PEW markers, low serum albumin (HR 3.18; P = 0.001) and low BMI (HR 1.97; P = 0.034) were the most significant predictors of death. Among the PEW status categories, moderate wasting (HR 3.43; P = 0.021) and severe wasting (HR 6.59; P = 0.001) were significant predictors of death. Diabetes, CVD, and inflammation were all additives in predicting death in association with severe wasting with a strongest HR (7.76; P < 0.001) for diabetic patients.

Conclusions

The nomenclature for PEW predicts mortality in our Afro-Caribbean MHD patients and help to identify patients at risk of severe wasting to provide adequate nutritional support.

Electronic supplementary material

The online version of this article (doi:10.1186/s40064-015-1257-3) contains supplementary material, which is available to authorized users.

Risk Score to Predict 1-Year Mortality after Haemodialysis Initiation in Patients with Stage 5 Chronic Kidney Disease under Predialysis Nephrology Care

Background

Few risk scores are available for predicting mortality in chronic kidney disease (CKD) patients undergoing predialysis nephrology care. Here, we developed a risk score using predialysis nephrology practice data to predict 1-year mortality following the initiation of haemodialysis (HD) for CKD patients.

Methods

This was a multicenter cohort study involving CKD patients who started HD between April 2006 and March 2011 at 21 institutions with nephrology care services. Patients who had not received predialysis nephrology care at an estimated glomerular filtration rate (eGFR) of approximately 10 mL/min per 1.73 m² were excluded. Twenty-nine candidate predictors were selected, and the final model for 1-year mortality was developed via multivariate logistic regression and was internally validated by a bootstrapping technique.

Results

A total of 688 patients were enrolled, and 62 (9.0%) patients died within one year of HD initiation. The following variables were retained in the final model: eGFR, serum albumin, calcium, Charlson Comorbidity Index excluding diabetes and renal disease (modified CCI), performance status (PS), and usage of erythropoiesis-stimulating agent (ESA). Their β-coefficients were transformed into integer scores: three points were assigned to modified CCI≥3 and PS 3–4; two to calcium>8.5 mg/dL, modified CCI 1–2, and no use of ESA; and one to albumin<3.5 g/dL, eGFR>7 mL/min per 1.73 m², and PS 1–2. Predicted 1-year mortality risk was 2.5% (score 0–4), 5.5% (score 5–6), 15.2% (score 7–8), and 28.9% (score 9–12). The area under the receiver operating characteristic curve was 0.83 (95% confidence interval, 0.79–0.89).

Conclusions

We developed a simple 6-item risk score predicting 1-year mortality after the initiation of HD that might help nephrologists make a shared decision with patients and families regarding the initiation of HD.

Phosphate binder pill burden, patient-reported non-adherence, and mineral bone disorder markers: Findings from the DOPPS

Because of multiple comorbidities, hemodialysis (HD) patients are prescribed many oral medications, including phosphate binders (PBs), often resulting in a high "pill burden." Using data from the international Dialysis Outcomes and Practice Patterns Study (DOPPS), we assessed associations between PB pill burden, patient-reported PB non-adherence, and levels of serum phosphorus (SPhos) and parathyroid hormone (PTH) using standard regression analyses. The study included data collected from 5262 HD patients from dialysis units participating in the DOPPS in 12 countries. PB prescription ranged from a mean of 7.4 pills per day in the United States to 3.9 pills per day in France. About half of the patients were prescribed at least 6 PB pills per day, and 13% were prescribed at least 12 PB pills per day. Overall, the proportion of patients who reported skipping PBs at least once in the past month was 45% overall, ranging from 33% in Belgium to 57% in the United States. There was a trend toward greater PB non-adherence and a higher number of prescribed PB pills per day. Non-adherence to PB prescription was associated with high SPhos (>5.5 mg/dL) and PTH (>600 pg/mL). Adherence to PB is a challenge for many HD patients and may be related to the number of PB pills prescribed. Prescription of a simplified PB regimen could improve patient adherence and perhaps improve SPhos and PTH levels.

Epidemiological profile of patients with end stage renal disease in a referral hospital in Cameroon

BACKGROUND

Data regarding the epidemiology of end-stage renal disease (ESRD) and dialysis in sub-Saharan Africa are scarce and knowledge about the spectrum renal disease is very limited. This study is on the profile of patients with ESRD in a referral hospital in Cameroon.

METHODS

Medical records of patients with ESRD covering a 10-year period of activities of the Douala General Hospital were reviewed. Data were retrieved on socio demographic, and clinical data such as major comorbidities, the presumed aetiology of ESRD, blood pressure, biological variables and renal replacement therapy.

RESULTS

In all 863 patients were included with 66% being men. Mean age was 47.4 years overall, 48.9 in men and 44.5 in women (p < 0.001). The main background aetiologies of ESRD were hypertension (30.9%), glomerulonephritis (15.8%), diabetes (15.9%), HIV (6.6%) and unknown (14.7%). Participants with HIV, glomerulonephritis or unknown background nephropathy were younger, more likely to be women, to be single and unemployed, while those with hypertension and/or diabetes were older, more likely to be men, to be either married or widow, and to be retired or working in the public sector. A total of 677 patients started haemodialysis with decreasing trend across age quartiles (p = 009), and variation across background nephropathies (p < 0.001). Emergency dialysis unplanned on a temporary catheter occurs in 88.3% of patients.

CONCLUSION

This study has revealed substantial gender and age differentials in the socio-demographic features and background nephropathy in patients with ESRD in this setting. The likelihood of starting maintenance dialysis varied across background nephropathies, driven at least in part by age differences across background nephropathies.

Improving outcomes by changing hemodialysis practice patterns

PURPOSE OF REVIEW

This review examines recent advances in understanding of how clinical outcomes for hemodialysis patients may be improved by achieving longer or more frequent treatment times, lower ultrafiltration rates (UFRs), improving nutritional status, and individualizing dialysate composition. This review also discusses the controversy related to timing of dialysis initiation.

RECENT FINDINGS

Many observational studies and several randomized controlled trials indicate longer dialysis treatment times, particularly nocturnal dialysis, and/or more frequent dialysis improve morbidity and mortality. Recent evidence also suggests that lower UFR and more consistent achievement of 'dry weight' may help minimize the damage from myocardial stunning and chronic volume overload that occurs in the majority of patients who receive conventional hemodialysis during the day with a standard schedule of 3-5 h, 3 times a week. Other aspects of the dialysis procedure such as appropriate estimated glomerular filtration rate for dialysis initiation and individualizing dialysate composition may also minimize cardiovascular risk. Finally, several studies have highlighted the benefits of oral nutritional supplementation (ONS) during dialysis.

SUMMARY

Greater treatment times per week with slower UFR, consistent attainment of 'dry weight', individualized dialysate prescriptions, and administration of ONS to malnourished patients are likely to reduce hospitalizations and improve survival in this high-risk population of end-stage renal disease patients.

Target weight gain during the first year of hemodialysis therapy is associated with patient survival

BACKGROUND

Hemodialysis (HD) patients are exposed to a high risk of death. Nutritional status has been recognized as a key factor for patient survival. Nutritional markers have been shown to improve after HD onset. In this study we have analyzed the dynamics of target weight (TGW) change and the evolution of other nutritional parameters during the first year of HD treatment and their influence on patients' outcomes.

METHODS

We have analyzed a retrospective cohort of incident patients starting HD therapy between January 2000 and January 2009, and studied the values and changes in TGW, interdialytic weight gain (IDWG), predialysis systolic blood pressure, serum albumin, protein intake, C-reactive protein (CRP) from the start and first week (W1), W8, W12, W26 and W52 in patients who survived the first year of therapy. We have analyzed the relationship between TGW changes with other nutritional parameters and the patient survival.

RESULTS

Among the cohort including 363 patients starting HD therapy, 251 (age 65.8 ± 14.8 years, 93 female/158 male, diabetes 36%) survived at least 1 year after dialysis onset and were followed for 44.9 months. During the first 8 weeks, the TGW decreased by 6.5 ± 5.6% (initial TGW change). The initial TGW change was correlated with IDWG at W12 and W26, and with changes in serum albumin and nPNA (normalized protein equivalent of nitrogen appearance) between HD W1 and W52 (respectively +7.8 and +11.4%). From W8 to W52, the TGW increased by +1.9 ± 7.4% (secondary TGW change). The Kaplan-Meier analysis displayed a significantly better survival in patients above the median (+2.3%) of the secondary TGW change (respectively -3.6 ± 5.2% and +7.6 ± 4.5%). The two groups above and below this median were not different according to age, diabetes or cardiovascular event history but the patients above the median had a significant higher IDWG and protein intake. In the Cox model analysis the patient overall mortality was related to age (p < 0.0001), to the secondary TGW change (p = 0.0001), and to the CRP level at W52 (p < 0.0001).

CONCLUSIONS

The initial fluid removal was related to nutritional markers. The secondary TGW change during the first year of HD treatment calculated after the initial phase of fluid removal was identified as a strong predictor of survival. It was associated with a better food intake whereas the patient case mix was not different. These data highlight the importance of nutrition and food intake in the first year of dialysis therapy and the need for nutritional follow-up and support in incident HD patients. It stresses the need in understanding the key factors associated with food intake in this setting.

Trends in infection-related hospital admissions and impact of length of time on dialysis among patients on long-term dialysis: a retrospective cohort study

BACKGROUND

After cardiovascular disease, infection is the second leading reason for admission to hospital among patients receiving long-term dialysis. We examined whether duration of dialysis treatment influences the rate of infection-related admission to hospital.

METHODS

Using provincial administrative databases for Quebec, we built a retrospective cohort of all adults receiving long-term dialysis (hemodialysis or peritoneal dialysis) between 2001 and 2007. We evaluated rates of infection-related admission to hospital according to length of time on dialysis.

RESULTS

A cohort of 9822 patients (mean age 66.3 [standard deviation ± 14.7] yr; 39.7% female) were followed for a median of 2.1 (range 1.0-3.9) years. Between 2001 and 2007, infection-related hospital admissions remained stable (from 0.20 to 0.19 per person-year; p = 0.7). All-cause hospital admission rates decreased by 22.9% (from 1.53 to 1.18 per person-year; p < 0.001), and cardiovascular-related admission rates decreased by 46.7% (from 0.45 to 0.24 per person-year; p < 0.001). The rate of infection-related admission remained stable with increasing time on dialysis (p = 0.1); however, both all-cause and cardiovascular-related admission rates decreased with length of time on dialysis (p < 0.001). Standardization of hospital admission rates by age, sex or length of time on dialysis did not change trends.

INTERPRETATION

We found a stable rate of infection-related hospital admission between 2001 and 2007 among patients on long-term dialysis, independent of age, sex and length of time on dialysis. A decrease in all-cause and cardiovascular-related admission rates during the same period meant that the proportion of admissions related to infection increased. Because admissions to hospital are potentially preventable, understanding the epidemiology of infection-related admissions may inform future studies on prevention of this serious outcome.