Cost-effectiveness of Accepting Kidneys From Deceased Donors With Common Cancers-A Modeling Study.

BACKGROUND: The disparity between the demand for and supply of kidney transplants has resulted in prolonged waiting times for patients with kidney failure. A potential approach to address this shortage is to consider kidneys from donors with a history of common cancers, such as breast, prostate, and colorectal cancers. METHODS: We used a patient-level Markov model to evaluate the outcomes of accepting kidneys from deceased donors with a perceived history of breast, prostate, or colorectal cancer characterized by minimal to intermediate transmission risk. Data from the Australian transplant registry were used in this analysis. The study compared the costs and quality-adjusted life years (QALYs) from the perspective of the Australian healthcare system between the proposed practice of accepting these donors and the conservative practice of declining them. The model simulated outcomes for 1500 individuals waitlisted for a deceased donor kidney transplant for a 25-y horizon. RESULTS: Under the proposed practice, when an additional 15 donors with minimal to intermediate cancer transmission risk were accepted, QALY gains ranged from 7.32 to 20.12. This translates to an approximate increase of 7 to 20 additional years of perfect health. The shift in practice also led to substantial cost savings, ranging between $1.06 and $2.3 million. CONCLUSIONS: The proposed practice of accepting kidneys from deceased donors with a history of common cancers with minimal to intermediate transmission risk offers a promising solution to bridge the gap between demand and supply. This approach likely results in QALY gains for recipients and significant cost savings for the health system.

Sex differences in cancer outcomes across the range of eGFR.

BACKGROUND AND HYPOTHESIS: People with chronic kidney disease (CKD) have increased incidence and mortality from most cancer types. We hypothesised that odds of presenting with advanced cancer may vary according to differences in eGFR, that this could contribute to increased all-cause mortality and that sex differences may exist. METHODS: Data were from Secure Anonymised Information Linkage Databank, including people with de-novo cancer diagnosis (2011-2017) and two kidney function tests within two years prior to diagnosis to determine baseline eGFR (mL/min/1.73m2). Logistic regression models determined odds of presenting with advanced cancer by baseline eGFR. Cox proportional hazards models tested associations between baseline eGFRcr and all-cause mortality. RESULTS: eGFR < 30 was associated with higher odds of presenting with advanced cancer of prostate, breast and female genital organs, but not other cancer sites. Compared to eGFR > 75-90, eGFR < 30 was associated with greater hazards of all-cause mortality in both sexes, but the association was stronger in females (female: HR 1.71, 95%CI 1.56-1.88; male versus female comparison HR 0.88, 95%CI 0.78-0.90). CONCLUSIONS: Lower or higher eGFR was not associated with substantially higher odds of presenting with advanced cancer across most cancer sites, but was associated with reduced survival. A stronger assocation with all-cause mortality in females compared to males with eGFR < 30 is concerning and warrants further scrutiny.

Sex and Gender Disparities in Living Kidney Donation: A Scoping Review.

Background: Women are more likely than men to be living kidney donors. We summarized the evidence concerning the reasons behind sex and gender disparities in living kidney donation (LKD). Methods: A scoping review of quantitative and qualitative evidence on reasons for sex and gender disparities in LKD was conducted from inception to March 2023. Results: Of 1123 studies screened, 45 were eligible for inclusion. Most studies were from North America, Europe, and Central Asia (n = 33, 73%). A predominance of women as living donors (55%-65%) was observed in 15 out of 18 (83%) studies. Reasons for sex and gender disparities in LKD included socioeconomic, biological, and cognitive or emotional factors. A gendered division of roles within the families was observed in most studies, with men being the primary income earner and women being the main caregiver. Fear of loss of income was a barrier to male donation. Human leukocyte antigen sensitization through pregnancy in female recipients precluded male partner donation, whereas female donation was supported by altruism and a positive attitude toward LKD. Conclusions: Sex imbalance in LKD is prevalent, with a predominance of women as living donors. Such disparities are driven by societal and cultural perceptions of gender roles, pregnancy-induced sensitization, and attitudes toward donation and at least some of these factors are modifiable. Donor compensation to support predonation assessments and income loss, implementation of innovative desensitization treatments, promotion of paired kidney exchange program, and targeted educational initiatives to promote equitable living donation may help to close the gender gap in LKD.

Sociodemographic Drivers of Donor and Recipient Gender Disparities in Living Kidney Donation in Australia.

Background: Females account for 60% of all living kidney donors worldwide. We defined the proportion of female to male donors for living donor kidney transplantation stratified by recipient gender, and explored the factors associated with female kidney donation. Methods: Data from the ANZDATA (Australian and New Zealand Dialysis and Transplantation) and ANZOD (Australian and New Zealand Organ Donor) registries (2002-2019) were used to identify the sociodemographic characteristics and their interactions associated with living donation from female donors. We derived the predicted probabilities from adjusted logistic models using marginal means. Results: Of 3523 living donor pairs, 2203 (63%) recipients were male, and 2012 (57%) donors were female. Male recipients were more likely to receive kidneys from female donors than male donors. Donor and recipient sex association was modified by donor-recipient relationship (P < 0.01), with sensitivity analysis suggesting that spousal donor-recipient pairs drive this interaction. Older recipients residing in regional or remote areas were more likely to receive kidneys from female donors compared with those from major cities (aged ≥60 years: 0.67 [0.63-0.71] vs. aged <60 years: 0.57 [0.53-0.60]). Conclusions: Factors associated with female donation include recipient sex, with spousal donors contributing to the interaction between recipient gender and donor-recipient relationship. Recipient age and location of residence have interactive effects on the likelihood of living donor transplantation from female donors.

Sex differences in associations between creatinine and cystatin C-based kidney function measures with stroke and major bleeding.

PURPOSE: We sought to explore whether adding kidney function biomarkers based on creatinine (eGFRCr), cystatin C (eGFRCys) or a combination of the two (eGFRCr-Cys) could improve risk stratification for stroke and major bleeding, and whether there were sex differences in any additive value of kidney function biomarkers. METHOD: We included participants from the UK Biobank who had not had a previous ischaemic or haemorrhagic stroke or major bleeding episode, and who had kidney function measures available at baseline. Cause-specific Cox proportional hazards models tested associations between eGFRCr, eGFRCys and eGFRCr-Cys (mL/min/1.73 m2) with ischaemic and haemorrhagic stroke, major bleeding (gastrointestinal or intracranial, including haemorrhagic stroke) and all-cause mortality. FINDINGS: Among 452,879 eligible participants, 246,244 (54.4%) were women. Over 11.5 (IQR 10.8-12.2) years, there were 3706 ischaemic strokes, 795 haemorrhagic strokes, 26,025 major bleeding events and 28,851 deaths. eGFRCys was more strongly associated with ischaemic stroke than eGFRCr: an effect that was more pronounced in women (men - HR: 1.16, 95% CI: 1.12-1.19; female to male comparison - HR: 1.11, 95% CI: 1.05-1.16, per 10 mL/min/1.73 m2 decline in eGFRCys). This interaction effect was also demonstrated for eGFRCr-Cys, but not eGFRCr. eGFRCys and eGFRCr-Cys were more strongly associated with major bleeding and all-cause mortality than eGFRCr in both men and women. Event numbers were small for haemorrhagic stroke. DISCUSSION: To a greater degree than is seen in men, eGFRCr underestimates risk of ischaemic stroke and major bleeding in women compared to eGFRCys. The difference between measures is likely explained by non-GFR biology of creatinine and cystatin C. CONCLUSION: Enhanced measurement of cystatin C may improve risk stratification for ischaemic stroke and major bleeding and clinical treatment decisions in a general population setting, particularly for women.

Cost-effectiveness of Kidney Transplantation From Donors at Increased Risk of Blood-borne Virus Infection Transmission.

BACKGROUND: Demand for donor kidneys outstrips supply. Using kidneys from selected donors with an increased risk of blood-borne virus (BBV) transmission (hepatitis B virus and hepatitis C virus [HCV], human immunodeficiency virus) may expand the donor pool, but cost-effectiveness of this strategy is uncertain. METHODS: A Markov model was developed using real-world evidence to compare healthcare costs and quality-adjusted life years (QALYs) of accepting kidneys from deceased donors with potential increased risk of BBV transmission, because of increased risk behaviors and/or history of HCV, versus declining these kidneys. Model simulations were run over a 20-y time horizon. Parameter uncertainty was assessed through deterministic and probabilistic sensitivity analyses. RESULTS: Accepting kidneys from donors at increased risk of BBVs (2% from donors with increased-risk behaviors and 5% from donors with active or past HCV infection) incurred total costs of 311 303 Australian dollars with a gain of 8.53 QALYs. Foregoing kidneys from these donors incurred total costs of $330 517 and a gain of 8.44 QALYs. A cost-saving of $19 214 and additional 0.09 QALYs (~33 d in full health) per person would be generated compared with declining these donors. Increasing the availability of kidneys with increased risk by 15% led to further cost-savings of $57 425 and additional 0.23 QALY gains (~84 d in full health). Probabilistic sensitivity analysis using 10 000 iterations showed accepting kidneys from donors at increased risk led to lower costs and higher QALY gains. CONCLUSIONS: Shifting clinical practice to accept increased BBV risk donors would likely produce lower costs and higher QALYs for health systems.

Cost-effectiveness of Interventions to Increase Utilization of Kidneys From Deceased Donors With Primary Brain Malignancy in an Australian Setting.

Kidneys from potential deceased donors with brain cancer are often foregone due to concerns of cancer transmission risk to recipients. There may be uncertainty around donors' medical history and their absolute transmission risk or risk-averse decision-making among clinicians. However, brain cancer transmissions are rare, and prolonging waiting time for recipients is harmful. Methods: We assessed the cost-effectiveness of increasing utilization of potential deceased donors with brain cancer using a Markov model simulation of 1500 patients waitlisted for a kidney transplant, based on linked transplant registry data and with a payer perspective (Australian government). We estimated costs and quality-adjusted life-years (QALYs) for three interventions: decision support for clinicians in assessing donor risk, improved cancer classification accuracy with real-time data-linkage to hospital records and cancer registries, and increased risk tolerance to allow intermediate-risk donors (up to 6.4% potential transmission risk). Results: Compared with current practice, decision support provided 0.3% more donors with an average transmission risk of 2%. Real-time data-linkage provided 0.6% more donors (1.1% average transmission risk) and increasing risk tolerance (accepting intermediate-risk 6.4%) provided 2.1% more donors (4.9% average transmission risk). Interventions were dominant (improved QALYs and saved costs) in 78%, 80%, and 87% of simulations, respectively. The largest benefit was from increasing risk tolerance (mean +18.6 QALYs and AU$2.2 million [US$1.6 million] cost-savings). Conclusions: Despite the additional risk of cancer transmission, accepting intermediate-risk donors with brain cancer is likely to increase the number of donor kidneys available for transplant, improve patient outcomes, and reduce overall healthcare expenditure.

Life Years Lost in Children with Kidney Failure: A Binational Cohort Study with Multistate Probabilities of Death and Life Expectancy.

SIGNIFICANCE STATEMENT: In children with kidney failure, little is known about their treatment trajectories or the effects of kidney failure on lifetime survival and years of life lost, which are arguably more relevant measures for children. In this population-based cohort study of 2013 children who developed kidney failure in Australia and New Zealand, most children were either transplanted after initiating dialysis (74%) or had a preemptive kidney transplant (14%). Life expectancy increased with older age at kidney failure, but more life years were spent on dialysis than with a functioning transplant. The expected (compared with the general population) number of life years lost ranged from 16 to 32 years, with female patients and those who developed kidney failure at a younger age experiencing the greatest loss of life years. BACKGROUND: Of the consequences of kidney failure in childhood, those rated as most important by children and their caregivers are its effects on long-term survival. From a life course perspective, little is known about the experience of kidney failure treatment or long-term survival. METHODS: To determine expected years of life lost (YLL) and treatment trajectory for kidney failure in childhood, we conducted a population-based cohort study of all children aged 18 years or younger with treated kidney failure in Australia (1980-2019) and New Zealand (1988-2019).We used patient data from the CELESTIAL study, which linked the Australian and New Zealand Dialysis and Transplant registry with national death registers. We estimated standardized mortality ratios and used multistate modeling to understand treatment transitions and life expectancy. RESULTS: A total of 394 (20%) of 2013 individuals died over 30,082 person-years of follow-up (median follow-up, 13.1 years). Most children (74%) were transplanted after initiating dialysis; 14% (18% of male patients and 10% of female patients) underwent preemptive kidney transplantation. Excess deaths (compared with the general population) decreased dramatically from 1980 to 1999 (from 41 to 22 times expected) and declined more modestly (to 17 times expected) by 2019. Life expectancy increased with older age at kidney failure, but more life years were spent on dialysis than with a functioning transplant. The number of YLL ranged from 16 to 32 years, with the greatest loss among female patients and those who developed kidney failure at a younger age. CONCLUSIONS: Children with kidney failure lose a substantial number of their potential life years. Female patients and those who develop kidney failure at younger ages experience the greatest burden.

AcceSS and Equity in Transplantation (ASSET) New Zealand: Protocol for population-wide data linkage platform to investigate equity in access to kidney failure health services in New Zealand.

BACKGROUND: Kidney transplantation is considered the ideal treatment for most people with kidney failure, conferring both survival and quality of life advantages, and is more cost effective than dialysis. Yet, current health systems may serve some people better than others, creating inequities in access to kidney failure treatments and health outcomes. AcceSS and Equity in Transplantation (ASSET) investigators aim to create a linked data platform to facilitate research enquiry into equity of health service delivery for people with kidney failure in New Zealand. METHODS: The New Zealand Ministry of Health will use patients' National Health Index (NHI) numbers to deterministically link individual records held in existing registry and administrative health databases in New Zealand to create the data platform. The initial data linkage will include a study population of incident patients captured in the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA), New Zealand Blood Service Database and the Australia and New Zealand Living Kidney Donor Registry (ANZLKD) from 2006 to 2019 and their linked health data. Health data sources will include National Non-Admitted Patient Collection Data, National Minimum Dataset, Cancer Registry, Programme for the Integration of Mental Health Data (PRIMHD), Pharmaceutical Claims Database and Mortality Collection Database. Initial exemplar studies include 1) kidney waitlist dynamics and pathway to transplantation; 2) impact of mental illness on accessing kidney waitlist and transplantation; 3) health service use of living donors following donation. CONCLUSION: The AcceSS and Equity in Transplantation (ASSET) linked data platform will provide opportunity for population-based health services research to examine equity in health care delivery and health outcomes in New Zealand. It also offers potential to inform future service planning by identifying where improvements can be made in the current health system to promote equity in access to health services for those in New Zealand.

Sex-Based Differences in Risk Factors and Complications of Chronic Kidney Disease.

Globally, females are ∼30% more likely to have pre-dialysis chronic kidney disease (CKD) than males for reasons that are not fully understood. CKD is associated with numerous adverse health outcomes which makes understanding and working to eradicating sex based disparities in CKD prevalence essential. This review maps both what is known, and what is unknown, about the way sex and gender impacts (1) the epidemiology and risk factors for CKD including age, diabetes, hypertension, obesity, smoking, and cerebrovascular disease, and (2) the complications from CKD including kidney disease progression, cardiovascular disease, CKD mineral and bone disorders, anaemia, quality-of-life, cancer and mortality. This mapping can be used to guide future research.

Polyoma BK Virus in Kidney Transplant Recipients: Screening, Monitoring, and Management.

Polyomavirus BK virus (BKPyV) infection is an important complication of kidney transplantation and allograft failure. The prevalence of viremia is 10%-15%, compared with BK-associated nephropathy (BKPyVAN) at 3%-5%. Given that there are no effective antiviral prophylaxis or treatment strategies for BKPyVAN, active screening to detect BKPyV viremia is recommended, particularly during the early posttransplant period. Immunosuppression reduction to allow viral clearance may avoid progression to severe and irreversible allograft damage. The frequency and duration of screening are highly variable between transplant centers because the evidence is reliant largely on observational data. While the primary treatment goals center on achieving viral clearance through immunosuppression reduction, prevention of subsequent acute rejection, premature graft loss, and return to dialysis remain as major challenges. Treatment strategies for BKPyV infection should be individualized to the recipient's underlying immunological risk and severity of the allograft infection. Efficacy data for adjuvant therapies including intravenous immunoglobulin and cidofovir are sparse. Future well-powered and high-quality randomized controlled trials are needed to inform evidence-based clinical practice for the management of BKPy infection.

Cancer transmissions and non-transmissions from solid organ transplantation in an Australian cohort of deceased and living organ donors.

Evidence on cancer transmission from organ transplantation is poor. We sought to identify cases of cancer transmission or non-transmission from transplantation in an Australian cohort of donors and recipients. We included NSW solid organ deceased donors 2000-2012 and living donors 2004-2012 in a retrospective cohort using linked data from the NSW Biovigilance Register (SAFEBOD). Central Cancer Registry (CCR) data 1972-2013 provided a minimum one-year post-transplant follow-up. We identified cancers in donors and recipients. For each donor-recipient pair, the transmission was judged likely, possible, unlikely, or excluded using categorization from international guidelines. In our analysis, transmissions included those judged likely, while those judged possible, unlikely, or excluded were non-transmissions. In our cohort, there were 2502 recipients and 1431 donors (715 deceased, 716 living). There were 2544 transplant procedures, including 1828 (72%) deceased and 716 (28%) living donor transplants. Among 1431 donors, 38 (3%) had past or current cancer and they donated to 68 recipients (median 6.7-year follow-up). There were 64 (94%) non-transmissions, and 4 (6%) transmissions from two living and two deceased donors (all kidney cancers discovered during organ recovery). Donor transmitted cancers are rare, and selected donors with a past or current cancer may be safe for transplantation.

Chronic Kidney Disease is a Risk Factor for Stroke.

Chronic kidney disease (CKD) is a sustained reduction in estimated glomerular filtration rate (eGFR), and/or presence of albuminuria. People with CKD have adverse cardiovascular outcomes including stroke. CKD and stroke share several risk factors, most notably older age, diabetes and hypertension, but CKD is also an independent risk factor for stroke. Relative burden of increased risk is worse for younger people and women, with <40 years with end stage CKD having more than 11 times the risk of their age-matched peers. Risk also varies by CKD treatment, with a risk peak for those starting dialysis, but dropping after the first month of treatment. Proposed mechanisms for increased risk are uraemia, cerebral blood flow dysregulation, vascular calcification, arterial stiffness, chronic inflammation, vascular access impacts, and for those on haemodialysis the use of anticoagulation to maintain dialysis circuits. Outcomes for people with CKD and stroke are poorer; functional outcomes may be impacted by reduced access to specialised stroke care. Stroke mortality is higher for those with CKD; with standardised mortality ratio more than three times higher than expected, but for some groups higher still (young women <40 years with a kidney transplant have 19 times the risk of stroke mortality than women without a transplant). Interventions to prevent and treat stroke lack the evidence base in CKD patients that is present for the general population.

Cardiac Mortality in Kidney Transplant Patients: A Population-based Cohort Study 1988-2013 in Australia and New Zealand.

BACKGROUND: Transplant recipients experience excess cardiac mortality. We compared circulatory death rates in Australian and New Zealand kidney transplant recipients to the general population and identified risk factors for circulatory death in kidney transplant recipients. METHODS: The primary cause of death for kidney transplant recipients aged ≥18 was established through ICD-10-AM codes using data linkage between the Australia and New Zealand dialysis and transplant registry and national death registers. We estimated standardized mortality ratios (SMRs) and developed a Fine-Gray competing risks model to determine risk factors for cardiac mortality. RESULTS: Of 5089 deaths in 16 329 kidney transplant recipients (158 325 person-years), 918 (18%) were cardiac. An increased risk of circulatory death was associated with older age (P < 0.001), male sex (P < 0.001), longer dialysis duration (P = 0.004), earlier era of transplantation (P < 0.001), ever graft failure (P < 0.001), known coronary artery disease (P = 0.002), and kidney failure from diabetes or hypertension (P < 0.001). The cardiac SMR was 5.4 [95% confidence interval (CI): 5.0-5.8], falling from 8.0 (95% CI: 4.9-13.1) in 1988 to 5.3 (95% CI: 4.0-7.0) in 2013 (P < 0.001). Females, particularly young ones, had significantly higher relative cardiac mortality than men. In recipients aged 40 years, the cardiac SMR was 26.5 (95% CI: 15.0-46.6) in females and 7.5 (95% CI: 5.0-11.1) for males. CONCLUSIONS: Cardiac risks remain elevated in kidney transplant recipients and may be under-recognized, and prevention and treatment interventions less accessed, less effective or even harmful in female recipients.