Zealand Dialysis Research Articles

Predictive Models for Recurrent Membranous Nephropathy After Kidney Transplantation.

Background.Recurrent membranous nephropathy (MN) posttransplantation affects 35% to 50% of kidney transplant recipients (KTRs) and accounts for 50% allograft loss 5 y after diagnosis. Predictive factors for recurrent MN may include HLA-D risk alleles, but other factors have not been explored with certainty.Methods.The Australian and New Zealand Dialysis and Transplant registry was used to develop 3 prediction models for recurrent MN (Group Least Absolute Shrinkage and Selection Operator [LASSO], penalized Cox regression, and random forest), which were tuned using tenfold cross-validation in a derivation cohort with complete HLA data. KTRs with MN but incomplete HLA data formed the validation cohort. Model performance was evaluated using area under the receiver operating characteristic curve (AUC-ROC).Results.One hundred ninety-nine KTRs with MN were included, and 25 (13%) had recurrent MN (median follow-up 5.9 y). The AUC-ROCs for Group LASSO, penalized Cox regression, and random forest models were 0.85 (95% confidence interval, 0.76-0.94), 0.91 (0.85-0.96), and 0.62 (0.57-0.69), respectively, in the derivation cohort, with moderate agreement in selected variables between the models (55%-70%). In their validation cohorts, the AUC-ROCs for Group LASSO and penalized Cox regression were 0.60 (0.49-0.70) and 0.73 (0.59-0.86), respectively. Variables of importance chosen by all models included recipient HLA-A2, donor HLA-DR12, donor-recipient HLA-B65, and HLA-DR12 match.Conclusions.A penalized Cox regression performed reasonably for predicting recurrent MN and was superior to Group LASSO and random forest models. These models highlighted the importance of donor-recipient HLA characteristics to recurrent MN, although validation in larger datasets is required.

Dialysis modality utilization patterns and mortality in older persons initiating dialysis in Australia and New Zealand

The benefits of dialysis in the older population remain highly debated, particularly for certain dialysis modalities. This study aimed to explore the dialysis modality utilisation patterns between in-centre haemodialysis (ICHD), peritoneal dialysis (PD) and home haemodialysis (HHD) and their association with outcomes in older persons. Older persons (≥75 years) initiating dialysis in Australia and New Zealand from 1999 to 2018 reported to the Australia and New Zealand Dialysis and Transplant (ANZDATA) registry were included. The main aim of the study was to characterise dialysis modality utilisation patterns and describe individual characteristics of each pattern. Relationships between identified patterns and survival, causes of death and withdrawal were examined as secondary analyses, where the pattern was considered as the exposure. A total of 10,306 older persons initiated dialysis over the study period. Of these, 6776 (66%) and 1535 (15%) were exclusively treated by ICHD and PD, respectively, while 136 (1%) ever received HHD during their dialysis treatment course. The remainder received both ICHD and PD: 906 (9%) started dialysis on ICHD and 953 (9%) on PD. Different individual characteristics were seen across dialysis modality utilisation patterns. Median survival time was 3.0 (95%CI 2.9-3.1) years. Differences in survival were seen across groups and varied depending on the time period following dialysis initiation. Dialysis withdrawal was an important cause of death and varied according to individual characteristics and utilisation patterns. This study showed that dialysis modality utilisation patterns in older persons are associated with mortality, independent of individual characteristics.

Evaluating data quality in the Australian and New Zealand dialysis and transplant registry using administrative hospital admission datasets and data-linkage.

Background: Clinical quality registries provide rich and useful data for clinical quality monitoring and research purposes but are susceptible to data quality issues that can impact their usage. Objective: This study assessed the concordance between comorbidities recorded in the Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry and those in state-based hospital admission datasets. Method: All patients in New South Wales, South Australia, Tasmania, Victoria and Western Australia recorded in ANZDATA as requiring chronic kidney replacement therapy (KRT) between 01/07/2000 and 31/12/2015 were linked with state-based hospital admission datasets. Coronary artery disease, diabetes mellitus, cerebrovascular disease, chronic lung disease and peripheral vascular disease recorded in ANZDATA at each annual census date were compared overall, over time and between different KRT modalities to comorbidities recorded in hospital admission datasets, as defined by the International Classification of Diseases (ICD-10-AM), using both the kappa statistic and logistic regression analysis. Results: 29, 334 patients with 207,369 hospital admissions were identified. Comparison was made at census date for every patient comparison. Overall agreement was "very good" for diabetes mellitus (92%, k = 0.84) and "poor" to "fair" (21-61%, k = 0.02-0.22) for others. Diabetes mellitus recording had the highest accuracy (sensitivity 93% (±SE 0.2) and specificity 93% (±SE 0.2)), and cerebrovascular disease had the lowest (sensitivity 54% (±SE 0.2) and specificity 21% (±SE 0.3)). The false positive rates for cerebrovascular disease, peripheral vascular disease and chronic airway disease ranged between 18 and 33%. The probability of a false positive was lowest for kidney transplant patients for all comorbidities and highest for patients on haemodialysis. Conclusions and Implications: Agreement between the clinical quality registry and hospital admission datasets was variable, with the prevalence of comorbidities being higher in ANZDATA.

The incidence of cancer recurrence and new cancer following commencement of dialysis.

ABSTRACTBackgroundPatients with kidney failure have a higher cancer risk compared with the age-matched general population. However, the outcomes of incident dialysis patients with a prior cancer history are unknown.MethodsUsing Australia and New Zealand Dialysis and Transplant Registry data (2000–2019), the outcomes and survival probabilities of incident dialysis patients with prior cancers and having experienced a cancer recurrence or having developed a new cancer after dialysis commencement were described.ResultsOf 4912 patients with prior cancers before dialysis commencement, 323 (7%) and 343 (7%) patients experienced cancer recurrence or developed new cancers after dialysis initiation, respectively. The median time from dialysis commencement to cancer recurrence was 1.2 years [interquartile range (IQR) 0.5–2.8] and was 2.0 years (IQR 0.7–4.0) for new cancer occurrence. Of those with cancer recurrence, 80% presented with metastatic disease and one in two patients died from cancer, with a median time from cancer recurrence to death of 0.5 years (IQR 0.2–1.7). Of those who developed new cancer, urinary tract and respiratory cancers were the most frequent cancer types, with a median time from new cancer diagnosis to death of 1.3 years (IQR 0.4–3.1). The 3-year survival probabilities on dialysis following cancer recurrence and new cancer were 19% [95% confidence interval (CI) 15–24] and 41% (35–47), respectively.ConclusionAmong incident dialysis patients with a prior cancer history, 14% experienced cancer recurrence or developed a new cancer. Patients who experienced cancer recurrence or developed new cancer have poor outcomes, with ˂50% surviving beyond 3 years. These findings suggest the need to have a greater understanding of the characteristics, cancer screening, treatment responses and reasons for commencing dialysis in patients with kidney failure and prior cancer history, which may help in the shared clinical decision-making process when considering dialysis for these patients.

The Symptom Monitoring with Feedback Trial (SWIFT): protocol for a registry-based cluster randomised controlled trial in haemodialysis

BackgroundKidney failure prevalence is increasing worldwide. Haemodialysis, peritoneal dialysis or kidney transplantation are undertaken to extend life with kidney failure. People receiving haemodialysis commonly experience fatigue, pain, nausea, cramping, itching, sleeping difficulties, anxiety and depression. This symptom burden contributes to poor health-related quality of life (QOL) and is a major reason for treatment withdrawal and death. The Symptom monitoring WIth Feedback Trial (SWIFT) will test the hypothesis that regular symptom monitoring with feedback to people receiving haemodialysis and their treating clinical team can improve QOL.MethodsWe are conducting an Australia and New Zealand Dialysis and Transplant (ANZDATA) registry-based cluster randomised controlled trial to determine the clinical- and cost-effectiveness at 12 months, of 3-monthly symptom monitoring using the Integrated Palliative Outcome Scale-Renal (IPOS-Renal) survey with clinician feedback, compared with usual care among adults treated with haemodialysis. Participants complete symptom scoring using a tablet, which are provided to participants and to clinicians. The trial aims to recruit 143 satellite haemodialysis centres, (up to 2400 participants). The primary outcome is change in health-related QOL, as measured by EuroQol 5-Dimension, 5-Level (EQ-5D-5L) instrument. Secondary outcomes include overall survival, symptom severity (including haemodialysis-associated fatigue), healthcare utilisation and cost-effectiveness.DiscussionSWIFT is the first registry-based trial in the Australian haemodialysis population to investigate whether regular symptom monitoring with feedback to participants and clinicians improves QOL. SWIFT is embedded in the ANZDATA Registry facilitating pragmatic recruitment from public and private dialysis clinics, throughout Australia. SWIFT will inform future collection, storage and reporting of patient-reported outcome measures (PROMs) within a clinical quality registry. As the first trial to rigorously estimate the efficacy and cost-effectiveness of routine PROMs collection and reporting in haemodialysis units, SWIFT will provide invaluable information to health services, clinicians and researchers working to improve the lives of those with kidney failure.Trial registrationAustralian New Zealand Clinical Trials Registry ACTRN12620001061921. Registered on 16 October 2020

Cancer Mortality in People Receiving Dialysis for Kidney Failure: An Australian and New Zealand Cohort Study, 1980-2013

Cancer is a significant cause of morbidity in the population with kidney failure; however, cancer mortality in people undergoing dialysis has not been well described. We sought to compare cancer mortality in people on dialysis for kidney failure with cancer mortality in the general population. A retrospective cohort study using linked health-administrative and dialysis registry data. All people receiving dialysis represented in the Australian and New Zealand Dialysis and Transplantation Registry, 1980-2013. Dialysis; hemodialysis (HD) and peritoneal dialysis (PD). Death and underlying cause of death ascertained using health administrative data and classified using International Classification of Diseases, Tenth Revision, Australian Modification (ICD-10-AM) codes. Indirect standardization on age at death, sex, year, and country to estimate standardized mortality ratios (SMR). Over 269,598 person years of observation, 34,100 deaths occurred among 59,648 people on dialysis, including 3,677 cancer deaths. The relative risk of all-site cancer death in dialysis was twice (SMR, 2.4 [95% CI, 2.33-2.49]) that of the general population and highest for oral and pharynx cancers (SMR, 24.3 [95% CI, 18.0-31.5]) and multiple myeloma (SMR, 22.5 [95% CI, 20.3-23.9]). Women on dialysis had a significantly higher risk of all-site cancer mortality (SMR, 2.7 [95% CI, 2.59-2.89]) compared with men (SMR, 2.3 [95% CI, 2.17-2.36]) (P< 0.001). People on HD (SMR, 2.2 [95% CI, 2.11-2.30]) experienced greater excess deaths from all-site cancer compared with people on PD (SMR, 1.3 [95% CI, 1.23-1.44]). Excess deaths have gradually decreased over time for all-site, multiple myeloma, and kidney cancers (P< 0.001) but have not kept up with improvements in the general population. By contrast, among people receiving dialysis, excess deaths increased for colorectal and lung cancers (P< 0.001). Confirmation of cancer diagnoses and population incidence data were not available; inability to exclude pre-existing cancers. People on dialysis experience excess all-site and site-specific cancer mortality compared with the general population. Mortality differs by modality type, age, and sex. Understanding the role of kidney failure and other morbidities in the treatment of cancer is important for shared decision-making regarding cancer treatments and identifying potential approaches to improve outcomes.

Association Between Side of Living Kidney Donation and Post-Transplant Outcomes.

Background: Right-sided living donor kidneys have longer renal arteries and shorter veins that make vascular anastomosis more challenging. We sought to determine whether recipients of right-sided living donor kidneys have worse outcomes than left-sided kidney recipients. Methods: An observational analysis of the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) was undertaken. We used adjusted logistic regression to determine the association between side and delayed graft function (DGF) and time-stratified adjusted cox regression models for graft and patient survivals. Results: Between 2004 and 2018, 4,050 living donor kidney transplants were conducted with 696 (17.2%) using right kidneys. With reference to left kidneys, the adjusted OR (95% CI) for DGF was 2.01 (1.31–3.09) for recipients with right kidneys. Within 30 days, 46 allografts (1.4%) were lost, with major causes of overall graft loss being technical, primary non-function and death. Recipients of right donor kidneys experienced a greater risk of early graft loss (aHR 2.02 [95% CI 1.06–3.86], p = 0.03), but not beyond 30 days (aHR 0.97 [95% CI 0.80–1.19], p = 0.8]). Conclusion: Technical challenge is the most common cause of early graft loss. The risk of early graft loss among recipients who received right kidneys is doubled compared to those who received left living donor kidneys.

Determinants of Perinatal Outcomes in Dialyzed and Transplanted Women in Australia

IntroductionDrivers of adverse perinatal outcomes in pregnancies of women receiving chronic kidney replacement therapy (KRT) remain poorly understood.MethodsBirths ≥ 20 weeks of gestation in Australian women receiving KRT were analyzed for perinatal outcomes stratified by maternal KRT exposure (dialysis or transplant, analyzed separately), by linking the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) and perinatal data sets (1991–2013).ResultsOf 2,948,084 babies (1,628,181 mothers), 248 were born to mothers receiving KRT (transplant, n = 211; dialysis, n = 37), with live birth rates ≥ 94%. The perinatal death rate was 162, 62, and 9 per 1000 births in the dialysis, transplant, and non-KRT cohorts, respectively. Babies exposed to KRT had increased odds of prematurity, small-for-gestational age (SGA), poor birth condition, resuscitation, intensive care admission, and longer hospitalization, with the dialysis cohort having worse outcomes. Preterm babies of dialyzed and transplanted mothers (compared with preterm babies with no KRT exposure) experienced 1.6- to 2.7-fold higher odds for all adverse outcomes, except birthweight < 2500 g, which was 11-fold higher for the dialysis cohort. In adjusted analyses, transplanted women with better allograft function (serum creatinine ≤ 120 μmol/l) still had >10-fold higher odds of preterm birth and low birthweight and 1.8- to 4.6-fold increased odds of other adverse outcomes. In transplanted women, mediation analysis revealed that pregnancy-induced hypertension contributed only a modest proportional effect (2.5%–11.2%) on adverse outcomes.ConclusionMaternal dialysis and transplantation conferred excess perinatal morbidity, particularly for preterm babies, and even in women with good preconception allograft function. Pregnancy-induced hypertension is not the predominant determinant of perinatal morbidity. Preconception counseling of women with kidney disease should encompass discussion of perinatal complications.

Immunosuppressant prescribing patterns in elderly kidney transplant recipients using registry data from Australia and New Zealand

AbstractBackgroundThe elderly is the fastest growing kidney transplant recipient group; however, they are more likely to die from immunosuppressant side effects than graft failure.AimThe aim of this study was to explore immunosuppressant prescribing practices in elderly kidney transplant recipients.MethodWe conducted a retrospective audit of registry data from the Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry between 2000 and 2015, to determine the actual prescribing trends of immunosuppressant drugs in elderly recipients (≥65 years). Drug choice and doses, prescribed initially and at 1‐year, were examined, with a survival analysis conducted to determine if drug regimen influenced graft survival.ResultsSix hundred and one elderly recipients were included in the analysis. Elderly patients were less likely to be prescribed tacrolimus at 1 year than younger patients, and median doses (149.3 vs 155.6 micrograms/kg; p &lt; 0.05) were significantly lower in elderly patients across the timeframe (initially and at 1‐year post‐transplant). We also observed that elderly recipients prescribed dual immunosuppressant therapy (compared to triple therapy) had an increased risk of graft loss (p &lt; 0.05).ConclusionBy examining Registry data across a 15‐year span, we observed differences in both immunosuppressant usage and drug dosing trends in elderly recipients. The implications of these findings may suggest that guidelines need adjustment to reflect this.

Mortality Trends After Transfer From Peritoneal Dialysis to Hemodialysis

IntroductionTransition to hemodialysis (HD) is a common outcome in peritoneal dialysis (PD), but the associated mortality risk is poorly understood. This study sought to identify rates of and risk factors for mortality after transitioning from PD to HD.MethodsPatients with incident PD (between 2000 and 2014) who transferred to HD for ≥1 day were identified, using data from Australia and New Zealand Dialysis and Transplantation registry (ANZDATA), Canadian Organ Replacement Register (CORR), Europe Renal Association (ERA) Registry, and the United States Renal Dialysis System (USRDS). Crude mortality rates were calculated for the first 180 days after transfer. Separate multivariable Cox models were built for early (<90 days), medium (90–180 days), and late (>180 days) periods after transfer.ResultsOverall, 6683, 5847, 21,574, and 80,459 patients were included from ANZDATA, CORR, ERA Registry, and USRDS, respectively. In all registries, crude mortality rate was highest during the first 30 days after a transfer to HD declining thereafter to nadir at 4 to 6 months. Crude mortality rates were lower for patients transferring in the most recent years (than earlier). Older age, PD initiation in earlier cohorts, and longer PD vintage were associated with increased risk of death, with the strongest associations during the first 90 days after transfer and attenuating thereafter. Mortality risk was lower for men than women <90 days after transfer, but higher after 180 days.ConclusionIn this multinational study, mortality was highest in the first month after a transfer from PD to HD and risk factors varied by time period after transfer. This study highlights the vulnerability of patients at the time of modality transfer and the need to improve transitions.

Time to Move on: HLA Matching Should Be Reconsidered in Modern Deceased Donor Kidney Allocation.

Background.HLA matching has been the cornerstone of deceased donor kidney allocation policies worldwide but can lead to racial inequity. Although HLA matching has been shown to improve clinical outcomes, the long-term impacts of nonallogenic factors are being increasingly recognized. This has led some transplant programs to include points for nonallogenic factors, for example, age. Our study looks at long-term graft and patient outcomes based on allocation cohorts rather than individual number of HLA mismatches.Methods.Using the Australia and New Zealand Dialysis and Transplant Registry, we analyzed 7440 adult deceased donor transplant events from 2000 to 2018. Transplants were classified as HLA matched or nonmatched according to the OrganMatch score and the local allocation algorithms. Graft function was studied with linear mixed modeling and graft rejection with logistic and binomial regression. Time to graft failure and recipient survival were examined with Kaplan–Meier curve and Cox regression models.Results.Forty percent of transplants were HLA matched. Mean glomerular filtration rate was 1.76 mL/min/1.73 m2 higher in the matched transplants (P < 0.001). Matched transplants had longer time to graft failure (15.9 versus 12.7 y; P < 0.001) and improved recipient survival (risk of death hazard ratio, 0.83; P = 0.003). Matched recipients spent less time on dialysis (28.1 versus 44.8 mo; P < 0.001), and this significantly contributed to the benefits seen in graft loss and recipient survival. Caucasian recipients were more likely to receive a matched transplant than non-Caucasians.Conclusions.Matched transplants showed benefits in graft and recipient outcomes; however, some of these results were of small magnitude, whereas others seemed to be due in part to a reduction in time on dialysis. The benefit for the matched cohort came at the expense of the nonmatched cohort, who spent longer on dialysis and were more likely to be of a minority racial background.

Excess all-cause and cause-specific mortality for people with diabetes and end-stage kidney disease.

Excess mortality is high in the setting of diabetes and end-stage kidney disease (ESKD), but the effects of ESKD beyond diabetes itself remains incompletely understood. We examined excess mortality in people with diabetes with versus without ESKD, and variation by age, sex and diabetes type. This study included 63,599 people with type 1 (aged 20-69years; 56% men) and 1,172,160 people with type 2 diabetes (aged 30+ years; 54% men), from the Australian National Diabetes Services Scheme. Initiation of renal replacement therapy and mortality outcomes were obtained via linkage to the Australia and New Zealand Dialysis and Transplant Registry and the National Death Index, respectively. Excess mortality was measured by calculating the mortality rate ratio (MRR) for people with versus without ESKD via indirect standardisation. A total of 9027 people developed ESKD during 8,601,522 person-years of follow-up. Among people with type 1 diabetes, the MRR was 34.9 (95%CI: 16.6-73.1) in men and 41.5 (20.8-83.1) in women aged 20-29years and was 5.6 (4.5-7.0) and 7.4 (5.5-10.1) in men and women aged 60-69years, respectively. In type 2 diabetes, MRRs were 16.6 (8.6-31.8) and 35.8 (17.0-75.2) at age 30-39years and were 2.8 (2.6-3.1) and 3.6 (3.2-4.1) at age 80+ years in men and women, respectively. Excess cause-specific mortality was highest for peripheral artery disease, cardiac arrest, and infections, and lowest for cancer. Among people with diabetes, excess mortality in ESKD is much higher at younger ages and is higher for women compared with men.

Age-dependent Sex Differences in Graft Loss After Kidney Transplantation.

Sex differences in kidney graft loss rates were reported in the United States. Whether these differences are present in other countries is unknown. We estimated the association between recipient sex and death-censored graft loss in patients of all ages recorded in the Scientific Registry of Transplant Recipients, Australia and New Zealand Dialysis and Transplant Registry, and Collaborative Transplant Study registries who received a first deceased donor kidney transplant (1988-2019). We used multivariable Cox regression models, accounting for the modifying effects of donor sex and recipient age, in each registry separately; results were combined using individual patient data meta-analysis. We analyzed 438 585 patients. Young female patients 13-24 y old had the highest crude graft loss rates (female donor: 5.66; male donor: 5.50 per 100 person-years). Among young recipients of male donors, females showed higher graft loss risks than males (0-12 y: adjusted hazard ratio [aHR] 1.42, (95% confidence interval [CI], 1.17-1.73); 13-24 y: 1.24 (1.17-1.32); 25-44 y: 1.09 (1.06-1.13)). When the donor was female, there were no significant differences by recipient sex among those of age <45 y; however, the aHR for females was 0.93 (0.89-0.98) in 45-59 y-old and 0.89 (0.86-0.93) in ≥ 60 y-old recipients. Findings were similar for all 3 registries in most age intervals; statistically significant heterogeneity was seen only among 13-24-y-old recipients of a female donor (I2 = 71.5%, P = 0.03). There is an association between recipient sex and kidney transplantation survival that is modified by recipient age and donor sex.

Peritoneal Dialysis Associated Peritonitis Rate – Validation of a Simplified Formula

Peritonitis is the most important therapy-related complication of peritoneal dialysis (PD). Unfortunately, many PD centers around the world do not accurately record peritonitis rate, mainly because they cannot ascertain PD patient time-at-risk from “patient flow” data - that is, calculating PD patient-days from dates when patients start and finish PD. We propose a simplified method of calculating PD peritonitis rate using PD patient time-at-risk from “patient stock” data - - that is, calculating PD patient-days from the number of prevalent PD patients at the center at the start of the year and the corresponding number at the end. We compared gold-standard measurements of annual PD peritonitis rates with simplified ones in the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) / New Zealand (NZ) PD Registry, and Le Registre de Dialyse Péritonéale de Langue Française et hémodialyse à domicile (the RDPLF). A total of 268 centers from 9 countries with 4311 center-years and 110,185 patient-years of follow-up were modelled. Overall agreement was excellent with a concordance correlation coefficient of 0.978 (95% confidence interval [CI] 0.975-0.980) in ANZDATA / NZ PD Registry, and 0.978 (0.977-0.980) in the RDPLF. There was statistically significant lower agreement for smaller centers in the registries at 0.972 (0.966-0.976) and 0.973 (0.970-0.976) respectively, although the performance of the simplified formula remains clinically sound in even these centers. The simplified method of calculating PD peritonitis rate is accurate, and will allow more centers around the world to measure, report, and work on reducing PD peritonitis rates.

Burden of kidney failure from atheroembolic disease and association with survival in people receiving dialysis in Australia and New Zealand: a multi-centre registry study

BackgroundCardiovascular disease is a leading cause of mortality in kidney failure (KF). Patients with KF from atheroembolic disease are at higher risk of cardiovascular disease than other causes of KF. This study aimed to determine survival on dialysis for patients with KF from atheroembolic disease compared with other causes of KF.MethodsAll adults (≥ 18 years) with KF initiating dialysis as the first kidney replacement therapy between 1 January 1990 and 31 December 2017 according to the Australia and New Zealand Dialysis and Transplant registry were included. Patients were grouped into either: KF from atheroembolic disease and all other causes of KF. Survival outcomes were assessed by the Kaplan-Meier method and Cox regression analysis adjusted for patient-related characteristics.ResultsAmong 65,266 people on dialysis during the study period, 334 (0.5%) patients had KF from atheroembolic disease. A decreasing annual incidence of KF from atheroembolic disease was observed from 2008 onwards. Individuals with KF from atheroembolic disease demonstrated worse survival on dialysis compared to those with other causes of KF (HR 1.80, 95% confidence interval [CI] 1.61–2.03). The respective one- and five-year survival rates were 77 and 23% for KF from atheroembolic disease and 88 and 47% for other causes of KF. After adjustment for patient characteristics, KF from atheroembolic disease was not associated with increased patient mortality (adjusted HR 0.93 95% CI 0.82–1.05).ConclusionsSurvival outcomes on dialysis are worse for individuals with KF from atheroembolic disease compared to those with other causes of KF, probably due to patient demographics and higher comorbidity.

Sex differences in mortality among binational cohort of people with chronic kidney disease: population based data linkage study

ObjectiveTo evaluate sex differences in mortality among people with kidney failure compared with the general population.DesignPopulation based cohort study using data linkage.SettingThe Australian and New Zealand Dialysis and Transplant Registry...

Representativeness of the PDOPPS cohort compared to the Australian PD population.

The Peritoneal Dialysis Outcomes and Practice Patterns Study (PDOPPS) is an international, prospective study following persons treated by peritoneal dialysis (PD) to identify modifiable practices associated with improvements in PD technique and person survival. The aim of this study was to assess the representativeness of the Australian cohort included in PDOPPS compared to the complete Australian PD population, as reported to the Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry. Adults with at least one PD treatment reported to ANZDATA Registry during the census period of PDOPPS Phase I (November 2014 to April 2018) were compared to the Australian PDOPPS cohort. The primary outcomes were the representativeness of centres and persons. Secondary outcomes explored the association of person characteristics with consent to study participation. After data linkage, 511 PDOPPS participants were compared to 5616 Australians treated with PD. Within centres eligible for PDOPPS, selected centres were similar to other Australian centres. The PDOPPS participants' cohort tended to include older persons, more males, a higher proportion of Caucasians and more persons with higher socioeconomic advantage compared to the Australian PD population. Differences in distribution across sex and ethnicities between the PDOPPS cohort and the overall PD population were in part due to the selection and consent processes, during which females and non-Caucasians were more likely to not consent to PDOPPS participation. Sampling methods used in PDOPPS allowed for good national representativeness of the included centres. However, representativeness of the unweighted PDOPPS sample was suboptimal in regard to some participant characteristics.

Changes in excess mortality among adults with diabetes-related end-stage kidney disease: a comparison between the USA and Australia.

The number of people with diabetes-related end-stage kidney disease (ESKD-DM) has doubled in the last two decades. We examined changes in excess mortality for people with ESKD-DM in the USA and Australia. In this retrospective cohort study, we included adults (ages 20-84 years) receiving renal replacement therapy (RRT) for ESKD-DM in the USA (n=1 178 860 from the United States Renal Data System, 2002-17) and Australia (n=10381 from the Australia and New Zealand Dialysis and Transplant Registry, 2002-13). ESKD-DM was defined as those with diagnosed diabetes at time of RRT initiation and mortality status was captured from national death registries. Annual standardized mortality ratios (SMR) were stratified by treatment modality, and age, sex and race (USA only). Trends were assessed using join point regression and annual percent change (APC) was reported. Overall, in the dialysis population SMR decreased from 2006 to 2014 in the USA (from 12.0 to 10.1; APC -2.1) and from 2002 to 2013 in Australia (from 12.0 to 9.4; APC -3.4). In the transplant population, SMR decreased from 6.2 to 4.0 from 2002 to 2013 in the USA, and did not significantly change from 2002 to 2013 in Australia. By subgroup, excess mortality was higher in women (versus men), younger (versus older) adults, dialysis (versus transplant) patients, and in Asian or Pacific Islanders and American Indian or Alaskan Natives (AI/AN) (versus Whites and Blacks). SMRs declined similarly across all subgroups excluding AI/AN (USA) and transplant patients (Australia), where relative declines were smaller. Excess mortality for people with ESKD-DM treated with dialysis or transplant has decreased in the USA and Australia, but progress has stalled from ∼2013 in the USA. Nevertheless, mortality remains more than nine times higher in ESKD-DM versus the general population, with important variations by subgroups. Given the increasing burden of diabetes in the population, a focus on reducing excess mortality risk in the ESKD-DM population is needed.

Young adult onset type 2 diabetes versus type 1 diabetes: Progression to and survival on renal replacement therapy.

Young-onset type 2 diabetes is an aggressive disease characterized by development of diabetic complications, including nephropathy, early in the disease course. However, within the cohort of young-onset type 1 and type 2 diabetes there are limited comparative data regarding progression to ESKD requiring renal replacement therapy or renal-related death (RRT/RRD). Probabilistic linkage of data from the RPAH Diabetes Centre, National Death Index and Australian and New Zealand Dialysis and Transplant Registry was undertaken. Cumulative Incidence Competing Risk and Cox Proportional Hazards Modelling approaches were utilized to examine progression to ESKD in young-onset type 1 and type 2 diabetes (age of diagnosis 15-35years). Unadjusted incidence rates (95% CI) of RRT/RRD in young-onset type 1 and type 2 diabetes were 3.1 (2.3-4.0) and 4.6 (3.7-5.7) per 1000 person years respectively. After adjustment for gender, ethnicity and duration of diabetes, the HR (95% CI) of RRT/RRD in young-onset type 2 diabetes was 2.0 (1.4-2.9). The HR remained higher after further adjustment for first available cholesterol, HbA1c and systolic blood pressure but not BMI. For those who progressed to RRT, prognosis was similar irrespective of diabetes type; cumulative incidence of mortality was 40% in both young-onset type 1 and type 2 diabetes after 6years of dialysis. Progression to RRT/RRD is greater in young-onset type 2 diabetes than in young-onset type 1 diabetes. The increased progression is associated with increased BMI. However, once ESKD is reached, individuals with young-onset type 1 and type 2 diabetes do equally poorly.

Early Graft Loss Following Transplantation From Expanded Criteria Donors.

Expanded criteria donor (ECD) kidneys are associated with higher graft loss rates than standard criteria donor kidneys. We sought to determine factors associated with early graft loss and their discrimination ability for this outcome compared with kidney donor risk index. Data were extracted from the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) for ECD transplants between 1997 and 2014. The primary outcome was early graft loss (all-cause graft loss within 3 y of transplantation). Death-censored graft loss was substituted as a sensitivity analysis. Era-adjusted odds ratios were calculated by multivariable logistic regression for donor, recipient, and transplant factors available at transplantation. Discrimination was assessed by c-statistic, with 95% confidence intervals (CIs) calculated by bootstrapping. Of 2152 ECD kidney transplants, early graft loss occurred in 406 (19%) and was associated with recipient diabetes, smoking, First Nations recipients, and oliguria. Of factors defining ECD (age, elevated terminal creatinine, hypertension, death from cerebrovascular accident), all but mode of death were associated with early graft loss. The multivariable model, including known donor, recipient, and transplant factors, was moderately good at predicting early graft loss (c-statistic 0.65; 95% CI, 0.62-0.68). Recipient factors (c-statistic 0.62; 95% CI, 0.59-0.65) performed equally well compared with donor factors (c-statistic 0.60; 95% CI, 0.57-0.64) or the kidney donor risk index (c-statistic 0.60; 95% CI, 0.56-0.63). Early graft loss occurs in approximately one-fifth of ECD kidney transplants. The discriminatory value of commonly used recipient, donor, and transplant factors are approximately comparable and limited.