Quantifying the Treatment Effect of Kidney Transplantation Relative to Dialysis on Survival Time: New Results Based on Propensity Score Weighting and Longitudinal Observational Data from Sweden

Understanding people's decisions when choosing or declining a kidney transplant: a qualitative evidence synthesis

OBJECTIVES

To synthesise qualitative research exploring patients' perspectives, experiences and factors influencing their decision-making preferences when choosing or declining kidney transplantation.

DESIGN

A qualitative evidence synthesis.

DATA SOURCES

Electronic databases were searched from 2000 to June 2021: PubMed, MEDLINE, CINAHL, Embase, PsycINFO, Web of Science, ProQuest Core Databases for Dissertations and Theses, and Google Scholar.

ELIGIBILITY CRITERIA

Qualitative studies exploring and reporting decision-making preferences of people with kidney disease, which reported influencing factors when choosing or declining kidney transplantation, published in English from high-income and middle-income countries.

DATA EXTRACTION AND SYNTHESIS

Titles were screened against the inclusion criteria. Thematic synthesis was done with the use of the Critical Appraisal Skills Programme qualitative checklist to assess study quality, and assessment of confidence in the qualitative findings was done using the Grading of Recommendation, Assessment, Development and Evaluation Confidence in the Evidence from Reviews of Qualitative Research.

FINDINGS

37 studies from 11 countries reported the perspectives of 1366 patients with kidney disease. Six descriptive themes were developed: decisional preferences influenced patients' readiness to pursue kidney transplantation, gathering sufficient information to support decision-making, navigating the kidney transplant assessment pathway, desire for kidney transplantation, opposed to kidney transplantation and uncertainties while waiting for the kidney transplant. A new enhanced theoretical model was developed to aid understanding of the complexities of decision-making in people with kidney disease, by integrating the Theory of Planned Behaviour and the Adaptive Decision Maker Framework to incorporate the novel findings.

CONCLUSION

The synthesis provides a better understanding of the extremely complex decision-making processes of people with kidney disease, which are aligned to their kidney transplantation preferences. Further research is needed to better understand the reasons for declining kidney transplantation, and to underpin development of personalised information, interventions and support for patients to make informed decisions when presented with kidney replacement options.

PROSPERO REGISTRATION NUMBER

CRD42021272588.

Healthcare costs after kidney transplantation compared to dialysis based on propensity score methods and real world longitudinal register data from Sweden

This study aimed to estimate the healthcare costs of kidney transplantation compared with dialysis using a propensity score approach to handle potential treatment selection bias. We included 693 adult wait-listed patients who started renal replacement therapy between 1998 and 2012 in Region Skåne and Stockholm County Council in Sweden. Healthcare costs were measured as annual and monthly healthcare expenditures. In order to match the data structure of the kidney transplantation group, a hypothetical kidney transplant date of persons with dialysis were generated for each dialysis patient using the one-to-one nearest-neighbour propensity score matching method. Applying propensity score matching and inverse probability-weighted regression adjustment models, the potential outcome means and average treatment effect were estimated. The estimated healthcare costs in the first year after kidney transplantation were €57,278 (95% confidence interval (CI) €54,467-60,088) and €47,775 (95% CI €44,313-51,238) for kidney transplantation and dialysis, respectively. Thus, kidney transplantation leads to higher healthcare costs in the first year by €9,502 (p = 0.066) compared to dialysis. In the following two years, kidney transplantation is cost saving [€36,342 (p < 0.001) and €44,882 (p < 0.001)]. For patients with end-stage renal disease, kidney transplantation reduces healthcare costs compared with dialysis over three years after kidney transplantation, even though the healthcare costs are somewhat higher in the first year. Relating the results of existing estimates of costs and health benefits of kidney transplantation shows that kidney transplantation is clearly cost-effective compared to dialysis in Sweden.

Women's Access to Kidney Transplantation in France: A Mixed Methods Research Protocol

Kidney transplantation is the best renal replacement therapy (medically and economically) for eligible patients with end-stage kidney disease. Studies in some French regions and in other countries suggest a lower access to the kidney transplant waiting listing and also to kidney transplantation, once waitlisted, for women. Using a mixed methods approach, this study aims to precisely understand these potential sex disparities and their causes. The quantitative study will explore the geographic disparities, compare the determinants of access to the waiting list and to kidney transplantation, and compare the reasons and duration of inactive status on the waiting list in women and men at different scales (national, regional, departmental, and census-block). The qualitative study will allow describing and comparing women's and men's views about their disease and transplantation, as well as nephrologists' practices relative to the French national guidelines on waiting list registration. This type of study is important in the current societal context in which the reduction of sex/gender-based inequalities is a major social expectation.

Survival Benefit of First Single-Organ Deceased Donor Kidney Transplantation Compared With Long-term Dialysis Across Ages in Transplant-Eligible Patients With Kidney Failure

IMPORTANCE

Kidney transplant is considered beneficial in terms of survival compared with continued dialysis for patients with kidney failure. However, randomized clinical trials are infeasible, and available evidence from cohort studies is at high risk of bias.

OBJECTIVE

To compare restricted mean survival times (RMSTs) between patients who underwent transplant and patients continuing dialysis across transplant candidate ages and depending on waiting time, applying target trial emulation methods.

DESIGN, SETTING, AND PARTICIPANTS

In this retrospective cohort study, patients aged 18 years or older appearing on the wait list for their first single-organ deceased donor kidney transplant between January 1, 2000, and December 31, 2018, in Austria were evaluated. Available data were obtained from the Austrian Dialysis and Transplant Registry and Eurotransplant and included repeated updates on wait-listing status and relevant covariates. Data were analyzed between August 1, 2019, and December 23, 2021.

EXPOSURES

A target trial was emulated in which patients were randomized to either receive the transplant immediately (treatment group) or to continue dialysis and never receive a transplant (control group) at each time an organ became available.

MAIN OUTCOMES AND MEASURES

The primary outcome was time from transplant allocation to death. Effect sizes in terms of RMSTs were obtained using a sequential Cox approach.

RESULTS

Among the 4445 included patients (2974 men [66.9%]; mean [SD] age, 52.2 [13.2] years), transplant was associated with increased survival time across all considered ages compared with continuing dialysis and remaining on the wait list within a 10-year follow-up. The estimated RMST differences were 0.57 years (95% CI, -0.14 to 1.84 years) at age 20 years, 3.01 years (95% CI, 2.50 to 3.54 years) at age 60 years, and 2.48 years (95% CI, 1.88 to 3.04 years) at age 70 years. The survival benefit for patients who underwent transplant across ages was independent of waiting time.

CONCLUSIONS AND RELEVANCE

The findings of this study suggest that kidney transplant prolongs the survival time of persons with kidney failure across all candidate ages and waiting times.

Clinical Effect of Revascularization Strategies and Pharmacologic Treatment on Long-Term Results in Patients with Advanced Peripheral Artery Disease with TASC C and D Femoropopliteal Lesions

Background

This study was to assess the clinical outcome and associated parameters of endovascular therapy (EVT group) and bypass surgery (bypass group) in patients with long femoropopliteal TransAtlantic Inter-Society Consensus II (TASC II) C and D peripheral artery disease (PAD).

Methods

187 patients who underwent successful EVT or bypass surgery were assessed. The endpoints included the events of cardiovascular disease (CVD) and lower-extremity amputation (LEA), 3-year primary patency, and 3-year amputation-free survival (AFS).

Results

The 3-year primary and secondary patency rates were better in the bypass group (P=0.007 and P=0.039, respectively), while the incidences of LEA, new CVD events, and mortality were comparable between groups. Weighted multivariate Cox analyses showed that cilostazol treatment (hazard ratio (HR): 0.46, 95% confidence interval (CI): 0.3–0.72, P=0.001), statin treatment (HR: 0.54, 95% CI: 0.33–0.9, P=0.014), and direct revascularization (DR) (HR: 0.47, 95% CI: 0.29–0.74, P=0.001) were predictive factors of 3-year primary patency. Kaplan–Meier curve analyses of time-to-primary cumulative AFS showed that nondiabetes mellitus, mild PAD, and cilostazol and statin treatment were correlated with a superior 3-year AFS (log rank test, P=0.001, P < 0.001, P=0.009, and P=0.044, respectively).

Conclusions

Endovascular stenting based on the angiosome concept and bypass surgery provide comparable benefits for the treatment of long, advanced femoropopliteal lesions after a short follow-up period, whereas cilostazol therapy for more than 3 months, aggressive treatment of dyslipidemia, and surgical revascularization were associated with higher primary patency.

Peritoneal Dialysis for Potential Kidney Transplant Recipients: Pride or Prejudice?

Kidney transplantation (KT) is recognized as the gold-standard of treatment for patients with end-stage renal disease. Additionally, it has been demonstrated that receiving a pre-emptive KT ensures the best recipient and graft survivals. However, due to an overwhelming discrepancy between the organs available and the patients on the transplant waiting list, the vast majority of transplant candidates require prolonged periods of dialysis before being transplanted. For many years, peritoneal dialysis (PD) and hemodialysis (HD) have been considered competitive renal replacement therapies (RRT). This dualistic vision has recently been questioned by evidence suggesting that an individualized and flexible approach may be more appropriate. In fact, tailored and cleverly planned changes between different RRT modalities, according to the patient’s needs and characteristics, are often needed in order to achieve the best results. While home HD is still under scrutiny in this particular setting, current data seems to favor the use of PD over in-center HD in patients awaiting a KT. In this specific population, the demonstrated advantages of PD are superior quality of life, longer preservation of residual renal function, lower incidence of delayed graft function, better recipient survival, and reduced cost.

Kynurenine pathway in kidney diseases

Kidney diseases have become one of the most common health care problems. Due to a growing number of advanced aged patients with concomitant disorders the prevalence of these diseases will increase over the coming decades. Despite available laboratory tests, accurate and rapid diagnosis of renal dysfunction has yet to be realized, and prognosis is uncertain. Moreover, data on diagnostic and prognostic markers in kidney diseases are lacking. The kynurenine (KYN) pathway is one of the routes of tryptophan (Trp) degradation, with biologically active substances presenting ambiguous properties. The KYN pathway is known to be highly dependent on immunological system activity. As the kidneys are one of the main organs involved in the formation, degradation and excretion of Trp end products, pathologies involving the kidneys result in KYN pathway activity disturbances. This review aims to summarize changes in the KYN pathway observed in the most common kidney disease, chronic kidney disease (CKD), with a special focus on diabetic kidney disease, acute kidney injury (AKI), glomerulonephritis and kidney graft function monitoring. Additionally, the importance of KYN pathway activity in kidney cancer pathogenesis is discussed, as are available pharmacological agents affecting KYN pathway activity in the kidney. Despite limited clinical data, the KYN pathway appears to be a promising target in the diagnosis and prognosis of kidney diseases. Modulation of KYN pathway activity by pharmacological agents should be considered in the treatment of kidney diseases.

Infectious events in kidney transplant recipients from deceased expanded criteria donors: a prospective cohort

OBJECTIVE

Analyze risk factors for infection in kidney transplant recipients from deceased expanded criteria donors (DECD) in the first two years of follow-up.

METHOD

This is a prospective cohort study with 466 patients from DECD who underwent kidney transplantation in 2015 and 2016 in Brazil. A total of 551 events were recorded. The largest incidence of infectious events occurred in the first month after kidney transplantation. Cytomegalovirus infection was the most common infectious episode.

RESULTS

The incidence rate of infections was 57.1%. Among bacterial infections, only 4% were due to multidrug-resistant microorganisms. The death rate was 3.3% (15) patients. The main cause of death was infectious (73.3%). Hospitalization until the first infection (aOR:1.61), Number of infections in 1 year (aOR:40.16), and Cytomegalovirus infection (aOR:13.84) was risk factors for infection by multidrug resistant microorganisms (MDR).

CONCLUSION

Infection incidence with MDR bacteria was high among kidney transplant recipients from DECD, and the main cause of death was infection. Survival was high among patients with infection.

Comparison of Outcomes of Kidney Transplantation From Extremely Low Body Weight ≤5kg Versus Larger Body Weight Pediatric Donors

Background

Kidney transplantation from donors who weigh ≤5 kg is performed at only a few transplant centers owing to the high complication and low graft survival rates associated with this approach.

Methods

We retrospectively compared the results of kidney transplantation at our center between January 2015 and December 2019 based on the following pediatric donor criteria: donor body weight ≤5 kg (n=32), 5 kg< donor weight ≤20 kg (n=143), and donor weight >20 kg (n=110). We also perform subgroup analysis of kidney transplantation outcomes from ≤5 kg donors, using conventional (dual separate and classic en-bloc KTx)/novel (en-bloc KTx with outflow tract) surgical methods and allocating to adult/pediatric recipients.

Results

The death-censored graft survival rates from extremely low body weight ≤5kg at 1 month, and 1, 3, and 5 years were 90.6%, 80.9%, 77.5%, and 73.9%, respectively, which were significantly lower than that from larger body weight pediatric donors. However, the 3-, and 5-year post-transplantation eGFRs were not significantly different between the pediatric and adult recipient group. The thrombosis (18.8%) and urinary leakage (18.8%) rates were significantly higher in the donor weight ≤5 kg group. Compared with 5 kg< donor weight ≤20 kg group, donor weight ≤5kg group was at elevated risk of graft loss due to thrombosis (OR: 13.4) and acute rejection (OR: 6.7). No significant difference on the outcomes of extremely low body weight donor kidney transplantation was observed between adults and pediatric recipients. Urinary leakage rate is significantly lower in the novel operation (8.7%) than in the conventional operation group (44.4%).

Conclusions

Although the outcomes of donor body weight ≤5kg kidney transplantation is inferior to that from donors with large body weight, it can be improved through technical improvement. Donors with body weight ≤5 kg can be considered as an useful source to expand the donor pool.