Identification of factors affecting access to Kidney transplant waiting list and outcomes among Indigenous Australians

Abstract

Improving access to the waiting list and kidney transplantation is one of the important factors in improving poor outcomes faced by Aboriginal and Torres Strait Islanders (Indigenous) Australians with end stage kidney disease (ESKD). This thesis was designed to address the following specific aims: · To identify the time to placement on the transplant waiting list and time to transplantation among Indigenous Australians as compared to non-indigenous Australians · To examine predictors of placement on the transplant waiting list (and nonlisting) for kidney transplantation utilising existing data from Australia and New Zealand Dialysis and Transplant Registry (ANZDATA), which holds waiting list data from the National Organ Matching System. · To examine relationships between Indigenous patients’ facility haemodialysis attendance and the chance of placement on the transplant waiting list, transplantation and transplant outcomes. · To identify risk factors predictive of good vs poor outcome following transplantation among Indigenous recipients, through quantitative studies utilising existing ANZDATA Registry data Research conducted for this thesis confirmed the increased use of haemodialysis along with low numbers of kidney transplantation among Indigenous Australians as compared to non-indigenous Australians. Lower numbers of kidney transplant among Indigenous Australians were further explored to find whether this related to placement on the transplant waiting list and to define the groups who were affected by this. A reduction in placement on the transplant waiting list among Indigenous Australians more so among people from remote areas was identified. A significant gap in transplantation among Indigenous Australians existed in and after the second year on the transplant waiting list. For this and other research conducted in this thesis, remoteness was defined by Australian Bureau of Statistics (ABS) remoteness categories, by linking ABS postcode of residence concordance data with the postcode recorded in the ANZDATA record for the start of RRT. Research conducted to explore the association of facility dialysis attendance in Indigenous Australians with ESKD and placement on the transplant waiting list and transplant outcomes was limited by the low number of outcomes measured. An association between placement on the transplant waiting list and transplant outcomes was not evident; however, the chance of transplantation was low among participants with dialysis attendance ≤2.5 sessions/week. Identification of risk factors predictive of good vs poor outcome following transplantation among Indigenous recipients was conducted by linkage of hospitalderived data with data from the Registry. A cohort study comparing pre and posttransplant hospitalisation among Indigenous kidney transplant recipients of South Australia and Northern Territory found increased rates of hospital admissions, prolonged hospital stay, and increased rates of infection more so in the first year post-transplant. Half of the study participants in our study cohort had delayed graft function. Total ischaemia time was more than 16 hours in half of the study population. Finally, a retrospective case-control study among Indigenous transplant recipients, to explore specific risks factors in the pre-transplant period, showed increased rates of hospitalisation to be predictive of early graft loss. No correlation was found between other studied factors and graft loss (including patients’ death). More studies, including studies to understand pharmacokinetics and pharmacodynamics of immunosuppression in Indigenous transplant recipients, are required to look for other factors not examined here. Hospitalisation in the pretransplant period needs further exploration and measures identified to reduce these events and complications which follow. Policies need to focus in the first year posttransplant to reduce the burden of hospitalisation. Individually tailored, evidencebased protocols are required to improve the management of post-transplant infections, which may include consideration of broad anti-infective agents. Finding ways to reduce ischaemia time and delayed graft function as a result of this factor need consideration. Development of algorithms and outcome predicting tools taking into account pretransplant hospitalisation into the equation may be helpful. Strategies need to be developed to increase placement on the transplant waiting list and transplant rates.