Effect of kidney replacement therapy modality after first kidney graft failure on second kidney transplantation outcomes

Outcomes of kidney replacement therapies after kidney transplant failure: A systematic review and meta-analysis

BACKGROUND

Following kidney transplant failure, patients generally have three kidney replacement therapy (KRT) options: peritoneal dialysis (PD), haemodialysis (HD), or pre-emptive kidney re-transplantation. This review aims to explore KRT options after kidney transplant failure and compare clinical outcomes.

METHOD

This review included studies from five databases: Medline, PubMed, Embase, Cochrane, and CINAHL. The study protocol was registered at PROSPERO [CRD42024514346]. Causes of kidney transplant failure were explored. Survival and re-transplantation rates among three groups after kidney transplant failure were compared: patients starting PD (TX-PD group), patients starting HD (TX-HD group), and patients re-transplanted without bridging dialysis (TX-TX group). Causes of death were also explored. The quality of the included studies was assessed using the CASP checklist and the meta-analysis was assessed using the GRADE approach.

RESULTS

Of 6405 articles, eight articles were included in the systematic review. Chronic damage was identified as the primary cause of kidney transplant failure. The TX-TX group had a lower mortality rate than the TX-HD group and TX-PD group, though this difference was only statistically significant in comparison to the TX-HD group (OR: 2.57; 95 % CI:1.58, 4.17; I2 = 79 %; P = 0.0001). Additionally, the TX-PD group had a significantly lower mortality rate (OR: 0.83; 95 % CI:0.76, 0.90; I2 = 88 %; P < 0.0001) and higher re-transplantation rate (OR: 1.56; 95 % CI:1.41, 1.73; I2 = 0 %; P < 0.00001) compared to the TX-HD group. Cardiovascular disease, infection, and cancer were the leading causes of death.

CONCLUSION

The TX-TX group had better survival than the TX-HD group. Survival and re-transplantation rates were higher in the TX-PD group than the TX-HD group. However, age and comorbidities may impact survival and re-transplantation rates between the TX-PD and TX-HD groups, which should be explored further.

Association between diabetic status and risk of all-cause and cause-specific mortality on dialysis following first kidney allograft loss

Background

Diabetes mellitus (DM) is associated with a greater risk of mortality in kidney transplant patients, primarily driven by a greater risk of cardiovascular disease (CVD)-related mortality. However, the associations between diabetes status at time of first allograft loss and mortality on dialysis remain unknown.

Methods

All patients with failed first kidney allografts transplanted in Australia and New Zealand between 2000 and 2020 were included. The associations between diabetes status at first allograft loss, all-cause and cause-specific mortality were examined using competing risk analyses, separating patients with diabetes into those with pre-transplant DM or post-transplant diabetes mellitus (PTDM).

Results

Of 3782 patients with a median (IQR) follow-up duration of 2.7 (1.1-5.4) years, 539 (14%) and 390 (10%) patients had pre-transplant DM or developed PTDM, respectively. In the follow-up period, 1336 (35%) patients died, with 424 (32%), 264 (20%) and 199 (15%) deaths attributed to CVD, dialysis withdrawal and infection, respectively. Compared to patients without DM, the adjusted subdistribution HRs (95% CI) for pre-transplant DM and PTDM for all-cause mortality on dialysis were 1.47 (1.17-1.84) and 1.47 (1.23-1.76), respectively; for CVD-related mortality were 0.81 (0.51-1.29) and 1.02 (0.70-1.47), respectively; for infection-related mortality were 1.84 (1.02-3.35) and 2.70 (1.73-4.20), respectively; and for dialysis withdrawal-related mortality were 1.71 (1.05-2.77) and 1.51 (1.02-2.22), respectively.

Conclusions

Patients with diabetes at the time of kidney allograft loss have a significant survival disadvantage, with the excess mortality risk attributed to infection and dialysis withdrawal.

Management of an aneurysmal arteriovenous fistula in kidney transplant recipients

Aneurysms remain the most common complication of an arteriovenous fistula created for dialysis access. The management of an aneurysmal arteriovenous fistula (AAVF) in kidney transplant recipients remains contentious with a lack of clear clinical guidelines. Recipients of a functioning graft do not require the fistula for dialysis access, however risk of graft failure and needing the access at a future date must be considered. In this review we outline the current evidence in the assessment and management of a transplant recipient with an AAVF. We will describe our recommended five-step approach to assessing an AAVF in transplant patients; 1.) Define AAVF 2.) Risk assess AAVF 3.) Assess transplant graft function and future graft failure risk 4.) Consider future renal replacement therapy options 5.) Vascular mapping to assess future vascular access options. Then we will describe the current therapeutic options and when they would most appropriately be employed.

Peritoneal dialysis discontinuation: to the root of the problem

As the global burden of chronic kidney disease continues to increase, the use of peritoneal dialysis is often advocated as the preferred initial dialysis modality. Observational studies suggest a survival advantage for peritoneal dialysis over hemodialysis for the initial 2-3 years of dialysis. Peritoneal dialysis has been associated with better graft survival after kidney transplantation and has a reduced cost burden compared to hemodialysis. However, several medical and non-medical reasons may limit access to peritoneal dialysis, and less than 20% of patients with end-stage kidney disease are treated with peritoneal dialysis worldwide. In this narrative review, we sought to summarize the recent medical literature on risk factors for peritoneal dialysis discontinuation, distinguishing the early and the late phase after peritoneal dialysis initiation. Although the definition of clinically relevant outcomes varies among studies, we observed that center size, older age, and the presence of many comorbidities are risk factors associated with peritoneal dialysis discontinuation, regardless of the phase after peritoneal dialysis initiation. On the contrary, poor technique training and late referral to nephrology care, as opposed to the need for a caregiver, patient burnout and frequent hospitalizations, are related to early and late peritoneal dialysis drop-out, respectively. The aim of the review is to provide an overview of the most relevant parameters to be considered when advising patients in the selection of the most appropriate dialysis modality and in the clinical management of peritoneal dialysis patients. In addition, we wish to provide the readers with a critical appraisal of current literature and a call for a consensus on the definition of clinically relevant outcomes in peritoneal dialysis to better address patients' needs.

Conservative Kidney Management in Kidney Transplant Populations

Conservative kidney management (CKM) has been increasingly accepted as a therapeutic option for seriously ill patients with advanced chronic kidney disease. CKM is active medical management of advanced chronic kidney disease without dialysis, with a focus on delaying the worsening of kidney disease and minimizing symptom burden. CKM may be considered a suitable option for kidney transplant recipients with poorly functioning and declining allografts, defined as patients with low estimated glomerular filtration rate (<20 mL/min per 1.73 m2) who are approaching allograft failure. CKM may be a fitting option for transplant patients facing high morbidity and mortality with or without dialysis resumption, and it should be offered as a choice for this patient population. In this review, we describe clinical considerations in caring for patients with poorly functioning and declining kidney allografts, especially the unique decision-making process around kidney replacement therapies. We discuss ways to incorporate CKM as an option for these patients. We also discuss financial and policy considerations in providing CKM for this population. Patients with poorly functioning and declining kidney allografts should be supported throughout transitions of care by an interprofessional and multidisciplinary team attuned to their unique challenges. Further research on when, who, and how to integrate CKM into existing care structures for patients with poorly functioning and declining kidney allografts is needed.