Incidence and Outcomes of Patients Receiving Chronic Kidney Replacement Therapy Admitted to Scottish ICUs Between 2009 and 2019-A National Observational Cohort Study.

OBJECTIVES: To determine the incidence and characteristics of ICU admissions in the Scottish population of patients treated with chronic kidney replacement therapy (KRT) over an 11-year period and determine factors associated with post-ICU admission mortality. DESIGN: Retrospective observational cohort study. SETTING: We analyzed admissions to Scottish intensive care environments between January 1, 2009, and December 31, 2019. PATIENTS: All patients receiving chronic KRT-including maintenance dialysis and kidney transplant-in Scotland. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: Descriptive statistics and factors associated with mortality using logistic regression and Cox proportional hazard models. From 10,657 unique individuals registered in the Scottish Renal Registry over the 11-year study period and alive as of January 1, 2009, 1,402 adult patients were identified as being admitted to a Scottish critical care setting. Between 2009 and 2019, admissions to ICU increased in a nonlinear manner driven by increases in admissions for renal causes and elective cardiac surgery. The ICU admission rate was higher among patients on chronic dialysis than in kidney transplant recipients (59.1 vs 19.9 per 1,000 person-years), but post-ICU mortality was similar (about 24% at 30 d and 40% at 1 year). Admissions for renal reasons were most common (20.9%) in patients undergoing chronic dialysis, whereas kidney transplant recipients were most frequently admitted for pneumonia (19.3%) or sepsis (12.8%). Adjusted Cox PH models showed that receiving invasive ventilation and vasoactive drugs was associated with an increased risk of death at 30 days post-ICU admission (HR, 1.75; 95% CI, 1.28-2.39 and 1.72; 95% CI, 1.28-2.31, respectively). CONCLUSIONS: With a growing population of kidney transplant recipients and the improved survival of patients on chronic dialysis, the number of ICU admissions is rising in the chronic KRT population. Mortality post-ICU admission is high for these patients.

High grade urothelial carcinoma in kidney transplant patients with a history of BK viremia - Just a coincidence?

INTRODUCTION: Kidney transplant recipients (KTR) have a three-to-four-fold increased risk of developing urothelial carcinoma (UC) compared to the general population. BK polyoma virus (BKV) infection is known to affect approximately 15% of KTR. In vitro models support a potential pathogenic role for BKV in the development of UC. We describe a series of UC in kidney transplant recipients. METHODS: Electronic patient records were searched to identify KTR with UC who had undergone kidney only or simultaneous kidney and pancreas transplantation in a single UK center between 2009 and 2015. Where available, stored pathological samples were retrieved, re-examined and stained for SV40 as a marker of BKV using standard staining protocols for kidney biopsy samples. RESULTS: Fourteen KTR had developed UC post-transplant. Of these, 10 KTR had a history of BKV infection post-transplant. Six of these 10 KTR developed a rare micropapillary tumor subtype of UC which is typically only found in <1% of UC cases. All six micropapillary tumor samples stained positive for SV40, including samples from metastases. Three tumor samples were available from the four KTR with no history of BKV infection and were not micropapillary subtype and were negative for SV40. Three micropapillary tumors from immunocompetent patients were examined as controls and were negative for SV40. CONCLUSIONS: These findings would support a pathogenic role for BK virus in the development of rare micropapillary subtype urothelial tumors in the kidney transplant population.

The Impact of Vaccination on Incidence and Outcomes of SARS-CoV-2 Infection in Patients with Kidney Failure in Scotland.

BACKGROUND: Patients with kidney failure requiring KRT are at high risk of complications and death following SARS-CoV-2 infection, with variable antibody responses to vaccination reported. We investigated the effects of COVID-19 vaccination on the incidence of infection, hospitalization, and death from COVID-19 infection. METHODS: The study design was an observational data linkage cohort study. Multiple health care datasets were linked to ascertain all SARS-CoV-2 testing, vaccination, hospitalization, and mortality data for all patients treated with KRT in Scotland from the start of the pandemic over a period of 20 months. Descriptive statistics, survival analyses, and vaccine effectiveness were calculated. RESULTS: As of September 19, 2021, 93% (n=5281) of the established KRT population in Scotland had received two doses of an approved SARS-CoV-2 vaccine. Over the study period, there were 814 cases of SARS-CoV-2 infection (15.1% of the KRT population). Vaccine effectiveness rates against infection and hospitalization were 33% (95% CI, 0 to 52) and 38% (95% CI, 0 to 57), respectively. Within 28 days of a SARS-CoV-2-positive PCR test, 9.2% of fully vaccinated individuals died (7% patients on dialysis and 10% kidney transplant recipients). This compares to <0.1% of the vaccinated general Scottish population admitted to the hospital or dying due to COVID-19 during that period. CONCLUSIONS: These data demonstrate that a primary vaccine course of two doses has limited effect on COVID-19 infection and its complications in patients with KRT. Adjunctive strategies to reduce risk of both COVID-19 infection and its complications in this population are urgently required.

Predicting renal disease progression in a large contemporary cohort with type 1 diabetes mellitus.

AIMS/HYPOTHESIS: The aim of this study was to provide data from a contemporary population-representative cohort on rates and predictors of renal decline in type 1 diabetes. METHODS: We used data from a cohort of 5777 people with type 1 diabetes aged 16 and older, diagnosed before the age of 50, and representative of the adult population with type 1 diabetes in Scotland (Scottish Diabetes Research Network Type 1 Bioresource; SDRNT1BIO). We measured serum creatinine and urinary albumin/creatinine ratio (ACR) at recruitment and linked the data to the national electronic healthcare records. RESULTS: Median age was 44.1 years and diabetes duration 20.9 years. The prevalence of CKD stages G1, G2, G3 and G4 and end-stage renal disease (ESRD) was 64.0%, 29.3%, 5.4%, 0.6%, 0.7%, respectively. Micro/macroalbuminuria prevalence was 8.6% and 3.0%, respectively. The incidence rate of ESRD was 2.5 (95% CI 1.9, 3.2) per 1000 person-years. The majority (59%) of those with chronic kidney disease stages G3-G5 did not have albuminuria on the day of recruitment or previously. Over 11.6 years of observation, the median annual decline in eGFR was modest at -1.3 ml min-1 [1.73 m]-2 year-1 (interquartile range [IQR]: -2.2, -0.4). However, 14% experienced a more significant loss of at least 3 ml min-1 [1.73 m]-2. These decliners had more cardiovascular disease (OR 1.9, p = 5 × 10-5) and retinopathy (OR 1.3 p = 0.02). Adding HbA1c, prior cardiovascular disease, recent mean eGFR and prior trajectory of eGFR to a model with age, sex, diabetes duration, current eGFR and ACR maximised the prediction of final eGFR (r2 increment from 0.698 to 0.745, p < 10-16). Attempting to model nonlinearity in eGFR decline or to detect latent classes of decliners did not improve prediction. CONCLUSIONS: These data show much lower levels of kidney disease than historical estimates. However, early identification of those destined to experience significant decline in eGFR remains challenging.

Changes in quality of life, health status and other patient-reported outcomes following simultaneous pancreas and kidney transplantation (SPKT): a quantitative and qualitative analysis within a UK-wide programme.

We examined quality of life (QoL) and other patient-reported outcome measures (PROMs) in 95 simultaneous pancreas and kidney transplant (SPKT) recipients and 41 patients wait-listed for SPKT recruited to the UK Access to Transplantation and Transplant Outcome Measures (ATTOM) programme. Wait-listed patients transplanted within 12 months of recruitment (n = 22) were followed 12 months post-transplant and compared with those still wait-listed (n = 19) to examine pre- to post-transplant changes. Qualitative interviews with ten SPKT recipients 12 months post-transplant were analysed thematically. Cross-sectional analyses showed several better 12-month outcomes for SPKT recipients compared with those still wait-listed, a trend to better health utilities but no difference in diabetes-specific QoL or diabetes treatment satisfaction. Pre- to post-transplant, SPKT recipients showed improved treatment satisfaction, well-being, self-reported health, generic QoL and less negative impact on renal-specific QoL (ps < 0.05). Health utility values were better overall in transplant recipients and neither these nor diabetes-specific QoL changed significantly in either group. Pre-emptive transplant advantages seen in 12-month cross-sectional analyses disappeared when controlling for baseline values. Qualitative findings indicated diabetes complications, self-imposed blood glucose monitoring and dietary restrictions continued to impact QoL negatively post-transplant. Unrealistic expectations of SPKT caused some disappointment. Measuring condition-specific PROMs over time will help in demonstrating the benefits and limitations of SPKT.

Long-term all-cause mortality and cardiovascular outcomes in Scottish children after initiation of renal replacement therapy: a national cohort study.

BACKGROUND: Data on long-term outcomes in children who have received renal replacement therapy (RRT) for end-stage renal disease are limited. METHODS: We studied long-term survival and incidence of fatal and nonfatal cardiovascular disease (CVD) events and determinants of these outcomes in children who initiated RRT between 1961 and 2013 using data from the Scottish Renal Registry (SRR). Linkage to morbidity records was available from 1981. RESULTS: A total of 477 children of whom 55% were boys, almost 50% had congenital urinary tract disease (CAKUT), 10% received a transplant as the first mode of RRT and almost 60% were over 11 years of age at start of RRT were followed for a median of 17.8 years (interquartile range (IQR) 8.7-26.6 years). Survival was 87.3% (95% confidence interval (CI) 84.0-90.1) at 10 years and 77.6% (95% CI 73.3-81.7) at 20 years. During a median follow-up of 14.96 years (IQR 7.1-22.9), 20.9% of the 381 patients with morbidity data available had an incident of CVD event. Age < 2 years at start of RRT, receiving dialysis rather than a kidney transplant and primary renal disease (PRD) other than CAKUT or glomerulonephritis (GN), were associated with a higher risk of all-cause mortality. Male sex, receiving dialysis rather than a kidney transplant and PRD other than CAKUT or GN, was associated with a higher risk of CVD incidence. CONCLUSIONS: Mortality and CVD incidence among children receiving RRT are high. PRD and RRT modality were associated with increased risk of both all-cause mortality and CVD incidence.

The impact of age on patient tolerance of mycophenolate following kidney transplantation.

BACKGROUND: In Scotland, standard maintenance immunosuppression following kidney transplantation consists of mycophenolate (MPA), tacrolimus and prednisolone irrespective of recipient age. We analyzed the tolerability of this immunosuppression regimen and the association with transplant outcomes. METHODS: A national, multicentre retrospective analysis of patients transplanted in 2015 and 2016, comparing graft function, acute rejection, significant infection rates and immunosuppression dosing between patients aged 18 and 59 years (Group 1) and ≥60 years (Group 2). RESULTS: Of the 490 patients, 26% were aged ≥60 years. Acute rejection (AR) rates at 1 year were 15% and 11% in Groups 1 and 2, respectively. Full-dose MPA was poorly tolerated with 53% in Group 1 and 77% in Group 2 requiring dose reduction or cessation. Female gender and age ≥60 years were independent predictors for MPA dose changes. One year following MPA dose reduction, AR risk was low (5%) in Group 2, however, those remaining on full dose MPA had a 79% increased rate of serious infections. CONCLUSION: The majority of renal transplant recipients aged ≥60 fail to tolerate full-dose MPA. In this group, MPA dose reduction is associated with low rejection rates, but full-dose MPA is associated with high infection rates. We suggest that a tailored approach to immunosuppression in elderly recipients incorporating lower doses of MPA may be appropriate.

COVID-19 in patients undergoing chronic kidney replacement therapy and kidney transplant recipients in Scotland: findings and experience from the Scottish renal registry.

BACKGROUND: Infection with the severe acute respiratory coronavirus 2 (SARS-CoV-2) has led to a worldwide pandemic with coronavirus disease 2019 (COVID-19), the disease caused by SARS-CoV-2, overwhelming healthcare systems globally. Preliminary reports suggest a high incidence of infection and mortality with SARS-CoV-2 in patients receiving kidney replacement therapy (KRT). The aims of this study are to report characteristics, rates and outcomes of all patients affected by infection with SARS-CoV-2 undergoing KRT in Scotland. METHODS: Study design was an observational cohort study. Data were linked between the Scottish Renal Registry, Health Protection Scotland and the Scottish Intensive Care Society Audit Group national data sets using a unique patient identifier (Community Health Index (CHI)) for each individual by the Public Health and Intelligence unit of Public Health, Scotland. Descriptive statistics and survival analyses were performed. RESULTS: During the period 1st March 2020 to 31st May 2020, 110 patients receiving KRT tested positive for SARS-CoV-2 amounting to 2% of the prevalent KRT population. Of those affected, 86 were receiving haemodialysis or peritoneal dialysis and 24 had a renal transplant. Patients who tested positive were older and more likely to reside in more deprived postcodes. Mortality was high at 26.7% in the dialysis patients and 29.2% in the transplant patients. CONCLUSION: The rate of detected SARS-CoV-2 in people receiving KRT in Scotland was relatively low but with a high mortality for those demonstrating infection. Although impossible to confirm, it appears that the measures taken within dialysis units coupled with the national shielding policy, have been effective in protecting this population from infection.

Limited health literacy is associated with reduced access to kidney transplantation.

Limited health literacy is common in patients with chronic kidney disease (CKD) and has been variably associated with adverse clinical outcomes. The prevalence of limited health literacy is lower in kidney transplant recipients than in individuals starting dialysis, suggesting selection of patients with higher health literacy for transplantation. We investigated the relationship between limited health literacy and clinical outcomes, including access to kidney transplantation, in a prospective UK cohort study of 2,274 incident dialysis patients aged 18-75 years. Limited health literacy was defined by a validated Single Item Literacy Screener (SILS). Multivariable regression was used to test for association with outcomes after adjusting for age, sex, socioeconomic status (educational level and car ownership), ethnicity, first language, primary renal diagnosis, and comorbidity. In fully adjusted analyses, limited health literacy was not associated with mortality, late presentation to nephrology, dialysis modality, haemodialysis vascular access, or pre-emptive kidney transplant listing, but was associated with reduced likelihood of listing for a deceased-donor transplant (hazard ratio [HR] 0.68; 95% confidence interval [CI] 0.51-0.90), receiving a living-donor transplant (HR 0.41; 95% CI 0.19-0.88), or receiving a transplant from any donor type (HR 0.65; 95% CI 0.44-0.96). Limited health literacy is associated with reduced access to kidney transplantation, independent of patient demographics, socioeconomic status, and comorbidity. Interventions to ameliorate the effects of low health literacy may improve access to kidney transplantation.

A national study of autogenous arteriovenous access use and patency in a contemporary hemodialysis population.

OBJECTIVE: The predicted outcomes of autogenous arteriovenous (AV) hemodialysis access creation are predominantly based on historical data; however, both the hemodialysis population and clinical practices have changed significantly during the last decade. This study examined contemporary AV access clinical use and patencies. METHODS: A multicenter observational cohort study was performed of all new AV accesses created in Scotland in 2015. The primary end point was efficacy assessed by successful AV access use for a minimum of 30 days and primary, primary assisted, and secondary patency at 1 year. Data obtained included all interventions to maintain or to restore patency. Predictors of patency loss including demographics, comorbid conditions, dialysis status, AV access location, duplex ultrasound surveillance, procedures, prior access, and antiplatelets were assessed. Kaplan-Meier and competing risks analyses were performed to estimate the probability of AV access failure. All patients were followed up for at least 1 year or had a censoring event. RESULTS: A total of 582 AV accesses were created in 537 patients (mean age, 60 [standard deviation, 14] years; 60% men; 42% with diabetes) in nine adult renal centers. Mean follow-up was 11.8 (standard deviation, 7.6) months. By the end of the follow-up, 322 (55.3%) AV accesses were successfully used for dialysis. At 1 year, 48% (95% confidence interval [CI], 44-52) of AV accesses had primary patency, (95% CI, 63-71) had primary assisted patency, and 69% (95% CI, 65-73) had secondary patency. The leading cause of primary patency loss was primary failure (30%). An average of 0.48 intervention per patient-year was required to maintain patency. On multivariable analysis, patency was better for an upper arm than for a forearm AV access (1-year secondary patency of upper arm vs forearm AV accesses, 74% vs 58%). The cumulative hazard and incident functions for AV access failure were 31% (95% CI, 27-35) and 23% (95% CI, 20-27) at 1 year, respectively. CONCLUSIONS: Despite advances in recent years with preoperative vessel assessment and surveillance, patency rates have not improved, with primary failure remaining the major obstacle. Competing events should be taken into consideration; otherwise, biases may occur with overestimation of the probability of AV access failure.

Renal replacement modality and stroke risk in end-stage renal disease-a national registry study.

Background: The risk of stroke in end-stage renal disease (ESRD) on renal replacement therapy (RRT) is up to 10-fold greater than the general population. However, whether this increased risk differs by RRT modality is unclear. Methods: We used data contained in the Scottish Renal Registry and the Scottish Stroke Care Audit to identify stroke in all adult patients who commenced RRT for ESRD from 2005 to 2013. Incidence rate was calculated and regression analyses were performed to identify variables associated with stroke. We explored the effect of RRT modality at initiation and cumulative dialysis exposure by time-dependent regression analysis, using transplant recipients as the reference group. Results: A total of 4957 patients commenced RRT for ESRD. Median age was 64.5 years, 41.5% were female and 277 patients suffered a stroke (incidence rate was 18.6/1000 patient-years). Patients who had stroke were older, had higher blood pressure and were more likely to be female and have diabetes. On multivariable regression older age, female sex, diabetes and higher serum phosphate were associated with risk of stroke. RRT modality at initiation was not. On time-dependent analysis, haemodialysis (HD) exposure was independently associated with increased risk of stroke. Conclusions: In patients with ESRD who initiate RRT, HD use independently increases risk of stroke compared with transplantation. Use of peritoneal dialysis did not increase risk on adjusted analysis.

Barriers to living donor kidney transplantation in the United Kingdom: a national observational study.

BACKGROUND: Living donor kidney transplantation (LDKT) provides more timely access to transplantation and better clinical outcomes than deceased donor kidney transplantation (DDKT). This study investigated disparities in the utilization of LDKT in the UK. METHODS: A total of 2055 adults undergoing kidney transplantation between November 2011 and March 2013 were prospectively recruited from all 23 UK transplant centres as part of the Access to Transplantation and Transplant Outcome Measures (ATTOM) study. Recipient variables independently associated with receipt of LDKT versus DDKT were identified. RESULTS: Of the 2055 patients, 807 (39.3%) received LDKT and 1248 (60.7%) received DDKT. Multivariable modelling demonstrated a significant reduction in the likelihood of LDKT for older age {odds ratio [OR] 0.11 [95% confidence interval (CI) 0.08-0.17], P < 0.0001 for 65-75 years versus 18-34 years}; Asian ethnicity [OR 0.55 (95% CI 0.39-0.77), P = 0.0006 versus White]; Black ethnicity [OR 0.64 (95% CI 0.42-0.99), P = 0.047 versus White]; divorced, separated or widowed [OR 0.63 (95% CI 0.46-0.88), P = 0.030 versus married]; no qualifications [OR 0.55 (95% CI 0.42-0.74), P < 0.0001 versus higher education qualifications]; no car ownership [OR 0.51 (95% CI 0.37-0.72), P = 0.0001] and no home ownership [OR 0.65 (95% CI 0.85-0.79), P = 0.002]. The odds of LDKT varied significantly between countries in the UK. CONCLUSIONS: Among patients undergoing kidney transplantation in the UK, there are significant age, ethnic, socio-economic and geographic disparities in the utilization of LDKT. Further work is needed to explore the potential for targeted interventions to improve equity in living donor transplantation.

Estimating Health-State Utility Values in Kidney Transplant Recipients and Waiting-List Patients Using the EQ-5D-5L.

OBJECTIVES: To report health-state utility values measured using the five-level EuroQol five-dimensional questionnaire (EQ-5D-5L) in a large sample of patients with end-stage renal disease and to explore how these values vary in relation to patient characteristics and treatment factors. METHODS: As part of the prospective observational study entitled "Access to Transplantation and Transplant Outcome Measures," we captured information on patient characteristics and treatment factors in a cohort of incident kidney transplant recipients and a cohort of prevalent patients on the transplant waiting list in the United Kingdom. We assessed patients' health status using the EQ-5D-5L and conducted multivariable regression analyses of index scores. RESULTS: EQ-5D-5L responses were available for 512 transplant recipients and 1704 waiting-list patients. Mean index scores were higher in transplant recipients at 6 months after transplant surgery (0.83) compared with patients on the waiting list (0.77). In combined regression analyses, a primary renal diagnosis of diabetes was associated with the largest decrement in utility scores. When separate regression models were fitted to each cohort, female gender and Asian ethnicity were associated with lower utility scores among waiting-list patients but not among transplant recipients. Among waiting-list patients, longer time spent on dialysis was also associated with poorer utility scores. When comorbidities were included, the presence of mental illness resulted in a utility decrement of 0.12 in both cohorts. CONCLUSIONS: This study provides new insights into variations in health-state utility values from a single source that can be used to inform cost-effectiveness evaluations in patients with end-stage renal disease.

Limited health literacy in advanced kidney disease.

Limited health literacy may reduce the ability of patients with advanced kidney disease to understand their disease and treatment and take part in shared decision making. In dialysis and transplant patients, limited health literacy has been associated with low socioeconomic status, comorbidity, and mortality. Here, we investigated the prevalence and associations of limited health literacy using data from the United Kingdom-wide Access to Transplantation and Transplant Outcome Measures (ATTOM) program. Incident dialysis, incident transplant, and transplant wait-listed patients ages 18 to 75 were recruited from 2011 to 2013 and data were collected from patient questionnaires and case notes. A score >2 in the Single-Item Literacy Screener was used to define limited health literacy. Univariate and multivariate analyses were performed to identify patient factors associated with limited health literacy. We studied 6842 patients, 2621 were incident dialysis, 1959 were wait-listed, and 2262 were incident transplant. Limited health literacy prevalence was 20%, 15%, and 12% in each group, respectively. Limited health literacy was independently associated with low socioeconomic status, poor English fluency, and comorbidity. However, transplant wait-listing, preemptive transplantation, and live-donor transplantation were associated with increasing health literacy.

Factors influencing withdrawal from dialysis: a national registry study.

BACKGROUND: Dialysis withdrawal is the third most common cause of death in patients receiving dialysis for established renal failure (ERF) in Scotland. We describe incidence, risk factors and themes influencing decision-making in a national renal registry. METHODS: Details of deaths in those receiving renal replacement therapy (RRT) for ERF in Scotland are reported to the Scottish Renal Registry via a unique mortality report. We extracted patient demographics and comorbidity, cause and location of death, duration of RRT and pertinent free text comments from 1 January 2008 to 31 December 2014. Withdrawal incidence was calculated and logistic regression used to identify significantly influential variables. Themes emerging from clinician comments were tabulated for descriptive purposes. RESULTS: There were 2596 deaths; median age at death was 68 [interquartile range (IQR) 58, 76] years, 41.5% were female. Median duration on RRT was 1110 (IQR 417, 2151) days. Dialysis withdrawal was the primary cause of death in 497 (19.1%) patients and withdrawal contributed to death in a further 442 cases (17.0%). The incidence was 41 episodes per 1000 patient-years. Regression analysis revealed increasing age, female sex and prior cerebrovascular disease were associated with dialysis withdrawal as a primary cause of death. Conversely, interstitial renal disease, angiographically proven ischaemic heart disease, valvular heart disease and malignancy were negatively associated. Analysis of free text comments revealed common themes, portraying an image of physical and psychological decline accelerated by acute illnesses. CONCLUSIONS: Death following dialysis withdrawal is common. Factors important to physical independence-prior cerebrovascular disease and increasing age-are associated with withdrawal. When combined with clinician comments this study provides an insight into the clinical decline affecting patients and the complexity of this decision. Early recognition of those likely to withdraw may improve end of life care.

Trends in dialysis modality choice and related patient survival in the ERA-EDTA Registry over a 20-year period.

BACKGROUND: Although previous studies suggest similar patient survival for peritoneal dialysis (PD) and haemodialysis (HD), PD use has decreased worldwide. We aimed to study trends in the choice of first dialysis modality and relate these to variation in patient and technique survival and kidney transplant rates in Europe over the last 20 years. METHODS: We used data from 196 076 patients within the European Renal Association-European Dialysis and Transplant Association (ERA-EDTA) Registry who started renal replacement therapy (RRT) between 1993 and 2012. Trends in the incidence rate and prevalence on Day 91 after commencing RRT were quantified with Joinpoint regression. Crude and adjusted hazard ratios (HRs) for 5-year dialysis patient and technique survival were calculated using Cox regression. Analyses were repeated using propensity score matching to control for confounding by indication. RESULTS: PD prevalence dropped since 2007 and HD prevalence stabilized since 2009. Incidence rates of PD and HD decreased from 2000 and 2009, respectively, while the incidence of kidney transplantation increased from 1993 onwards. Similar 5-year patient survival for PD versus HD patients was found in 1993-97 [adjusted HR: 1.02, 95% confidence interval (95% CI): 0.98-1.06], while survival was higher for PD patients in 2003-07 (HR: 0.91, 95% CI: 0.88-0.95). Both PD (HR: 0.95, 95% CI: 0.91-1.00) and HD technique survival (HR: 0.93, 95% CI: 0.87-0.99) improved in 2003-07 compared with 1993-97. CONCLUSIONS: Although initiating RRT on PD was associated with favourable patient survival when compared with starting on HD treatment, PD was often not selected as initial dialysis modality. Over time, we observed a significant decline in PD use and a stabilization in HD use. These observations were explained by the lower incidence rate of PD and HD and the increase in pre-emptive transplantation.

Predicting patient survival after deceased donor kidney transplantation using flexible parametric modelling.

BACKGROUND: The influence of donor and recipient factors on outcomes following kidney transplantation is commonly analysed using Cox regression models, but this approach is not useful for predicting long-term survival beyond observed data. We demonstrate the application of a flexible parametric approach to fit a model that can be extrapolated for the purpose of predicting mean patient survival. The primary motivation for this analysis is to develop a predictive model to estimate post-transplant survival based on individual patient characteristics to inform the design of alternative approaches to allocating deceased donor kidneys to those on the transplant waiting list in the United Kingdom. METHODS: We analysed data from over 12,000 recipients of deceased donor kidney or combined kidney and pancreas transplants between 2003 and 2012. We fitted a flexible parametric model incorporating restricted cubic splines to characterise the baseline hazard function and explored a range of covariates including recipient, donor and transplant-related factors. RESULTS: Multivariable analysis showed the risk of death increased with recipient and donor age, diabetic nephropathy as the recipient's primary renal diagnosis and donor hypertension. The risk of death was lower in female recipients, patients with polycystic kidney disease and recipients of pre-emptive transplants. The final model was used to extrapolate survival curves in order to calculate mean survival times for patients with specific characteristics. CONCLUSION: The use of flexible parametric modelling techniques allowed us to address some of the limitations of both the Cox regression approach and of standard parametric models when the goal is to predict long-term survival.

Understanding cost of care for patients on renal replacement therapy: looking beyond fixed tariffs.

BACKGROUND: In a number of countries, reimbursement to hospitals providing renal dialysis services is set according to a fixed tariff. While the cost of maintenance dialysis and transplant surgery are amenable to a system of fixed tariffs, patients with established renal failure commonly present with comorbid conditions that can lead to variations in the need for hospitalization beyond the provision of renal replacement therapy. METHODS: Patient-level cost data for incident renal replacement therapy patients in England were obtained as a result of linkage of the Hospital Episodes Statistics dataset to UK Renal Registry data. Regression models were developed to explore variations in hospital costs in relation to treatment modality, number of years on treatment and factors such as age and comorbidities. The final models were then used to predict annual costs for patients with different sets of characteristics. RESULTS: Excluding the cost of renal replacement therapy itself, inpatient costs generally decreased with number of years on treatment for haemodialysis and transplant patients, whereas costs for patients receiving peritoneal dialysis remained constant. Diabetes was associated with higher mean annual costs for all patients irrespective of treatment modality and hospital setting. Age did not have a consistent effect on costs. CONCLUSIONS: Combining predicted hospital costs with the fixed costs of renal replacement therapy showed that the total cost differential for a patient continuing on dialysis rather than receiving a transplant is considerable following the first year of renal replacement therapy, thus reinforcing the longer-term economic advantage of transplantation over dialysis for the health service.

How to routinely collect data on patient-reported outcome and experience measures in renal registries in Europe: an expert consensus meeting.

Despite the potential for patient-reported outcome measures (PROMs) and experience measures (PREMs) to enhance understanding of patient experiences and outcomes they have not, to date, been widely incorporated into renal registry datasets. This report summarizes the main points learned from an ERA-EDTA QUEST-funded consensus meeting on how to routinely collect PROMs and PREMs in renal registries in Europe. In preparation for the meeting, we surveyed all European renal registries to establish current or planned efforts to collect PROMs/PREMs. A systematic review of the literature was performed. Publications reporting barriers and/or facilitators to PROMs/PREMs collection by registries were identified and a narrative synthesis undertaken. A group of renal registry representatives, PROMs/PREMs experts and patient representatives then met to (i) share any experience renal registries in Europe have in this area; (ii) establish how patient-reported data might be collected by understanding how registries currently collect routine data and how patient-reported data is collected in other settings; (iii) harmonize the future collection of patient-reported data by renal registries in Europe by agreeing upon preferred instruments and (iv) to identify the barriers to routine collection of patient-reported data in renal registries in Europe. In total, 23 of the 45 European renal registries responded to the survey. Two reported experience in collecting PROMs and three stated that they were actively exploring ways to do so. The systematic review identified 157 potentially relevant articles of which 9 met the inclusion criteria and were analysed for barriers and facilitators to routine PROM/PREM collection. Thirteen themes were identified and mapped to a three-stage framework around establishing the need, setting up and maintaining the routine collection of PROMs/PREMs. At the consensus meeting some PROMs instruments were agreed for routine renal registry collection (the generic SF-12, the disease-specific KDQOL™-36 and EQ-5D-5L to be able to derive quality-adjusted life years), but further work was felt to be needed before recommending PREMs. Routinely collecting PROMs and PREMs in renal registries is important if we are to better understand what matters to patients but it is likely to be challenging; close international collaboration will be beneficial.

Mortality from infections and malignancies in patients treated with renal replacement therapy: data from the ERA-EDTA registry.

BACKGROUND: Infections and malignancies are the most common non-cardiovascular causes of death in patients on chronic renal replacement therapy (RRT). Here, we aimed to quantify the mortality risk attributed to infections and malignancies in dialysis patients and kidney transplant recipients when compared with the general population by age group and sex. METHODS: We followed 168 156 patients included in the ERA-EDTA registry who started RRT in 1993-2007 until 1 January 2012. Age- and cause-specific mortality rates per 1000 person-years (py) and mortality rate ratios (MRRs) compared with the European general population (WHO) were calculated. To identify risk factors, we used Cox regression. RESULTS: Infection-related mortality was increased 82-fold in dialysis patients and 32-fold in transplant recipients compared with the general population. Female sex, diabetes, cancer and multisystem disease were associated with an increased risk of infection-related mortality. The sex difference was most pronounced for dialysis patients aged 0-39 years, with women having a 32% (adjusted HR 1.32 95% CI 1.09-1.60) higher risk of infection-related mortality than men. Mortality from malignancies was 2.9 times higher in dialysis patients and 1.7 times higher in transplant recipients than in the general population. Cancer and multisystem disease as primary causes of end-stage renal disease were associated with higher mortality from malignancies. CONCLUSION: Infection-related mortality is highly increased in dialysis and kidney transplant patients, while the risk of malignancy-related death is moderately increased. Young women on dialysis may deserve special attention because of their high excess risk of infection-related mortality. Further research into the mechanisms, prevention and optimal treatment of infections in this vulnerable population is required.