Ineligibility for renal transplantation: prevalence, causes and survival in a consecutive cohort of 445 patients

Assessing survival post-kidney transplantation in Australia: A multivariable prediction model

AIM

Kidney transplantation remains the preferred standard of care for patients with kidney failure. Most patients do not access this treatment and wide variations exist in which patients access transplantation. We sought to develop a model to estimate post-kidney transplant survival to inform more accurate comparisons of access to kidney transplantation.

METHODS

Development and validation of prediction models using demographic and clinical data from the Australia and New Zealand Dialysis and Transplant Registry. Adult deceased donor kidney only transplant recipients between 2000 and 2020 were included. Cox proportional hazards regression methods were used with a primary outcome of patient survival. Models were evaluated using Harrell's C-statistic for discrimination, and calibration plots, predicted survival probabilities and Akaike Information Criterion for goodness-of-fit.

RESULTS

The model development and validation cohorts included 11 302 participants. Most participants were male (62.8%) and Caucasian (79.2%). Glomerulonephritis was the most common cause of kidney disease (45.6%). The final model included recipient, donor, and transplant related variables. The model had good discrimination (C-statistic, 0.72; 95% confidence interval (CI) 0.70-0.74 in the development cohort, 0.70; 95% CI 0.67-0.73 in the validation cohort and 0.72; 95% CI 0.69-0.75 in the temporal cohort) and was well calibrated.

CONCLUSION

We developed a statistical model that predicts post-kidney transplant survival in Australian kidney failure patients. This model will aid in assessing the suitability of kidney transplantation for patients with kidney failure. Survival estimates can be used to make more informed comparisons of access to transplantation between units to better measure equity of access to organ transplantation.

Center Hemodialysis Versus Peritoneal Dialysis: A Cost-Utility Analysis

Introduction Kidney replacement therapy (KRT) is needed for patients with end-stage kidney disease. While it is clear that kidney transplantation remains the gold standard in KRT, data comparing the cost-utility of peritoneal dialysis (PD) and hemodialysis (HD) are scarce. No such analysis has been performed for German patients.  Methods We used aggregated data generated by the Short Form 36 Health Survey (SF-36) for quality of life and insurance claims to evaluate mortality and economic impact. Quality-adjusted life years (QALY) and cost-utility were calculated accordingly.  Results PD is superior to HD within all dimensions of the SF-36, both in terms of QALY and cost-utility. The difference in cost per QALY between the aggregated physical dimensions (€50,671.54 vs. €39,745.77) is greater than that of the aggregated mental dimensions (€31,638.75 vs. €25,287.63). However, there is considerable variability among patients.  Conclusion From a health-economic point of view, PD should be preferred over HD when deciding on the KRT modality for the patient. This is not reflected in current practice, though. However, interindividual differences and patient preferences should be considered in the decision.

Kidney transplantation following iliac revascularization in severe atherosclerosis: a comparative study

BACKGROUND

Kidney transplantation (KT) has become the standard of care for patients with end-stage renal disease. However, as atherosclerosis progresses with time on dialysis, it causes increasing difficulties in implanting the graft. This is a comparative study analyzing complications and graft survival of recipients with iliac revascularization before transplantation.

METHODS

Between January 2006 and December 2015, 1691 kidney transplants were performed at our institution. We retrospectively analyzed eighteen patients with peripheral arterial disease (PAD) with the necessity of vascular revascularization before kidney transplantation to protect the inflow to the renal graft and to optimizing blood supply to the extremities. The primary endpoint included patient survival and graft survival. The secondary endpoints evaluate perioperative and early postoperative complication rates after kidney transplantation.

RESULTS

All patients enrolled in this study underwent two consecutive surgical procedures. No patient reported limb loss, and there was no additional perioperative morbidity or mortality related to the vascular procedure. Primary endpoints such as graft survival without dialysis and overall patient survival show 1-month survival of 100%, 1-year survival of 94.1%, and 5-year survival of 84.70%, respectively. One graft failure occurred 8 months after transplantation due to acute rejection, and there were two deaths over follow-up period due to myocardial infarction.

CONCLUSIONS

Vascular repair before kidney transplantation is safe, and results are suggestive that it prolongs graft survival. These promising results should encourage other centers to address vascular repair before the transplantation to optimize blood supply to the extremity and the future graft. Although, the interpretation of our results must be cautiously because of the small and heterogeneous sample size, and the limitations of retrospective study design. Prospective trials with larger study populations are needed to confirm the results of this study and to identify significant differences.

Ipsilateral Aorto-Iliac Calcification is Not Directly Associated With eGFR After Kidney Transplantation: A Prospective Cohort Study Analyzed Using a Linear Mixed Model

Aorto-iliac calcification (AIC) is a well-studied risk factor for post-transplant cardiovascular events and mortality. Its effect on graft function remains unknown. The primary aim of this prospective cohort study was to assess the association between AIC and estimated glomerular filtration rate (eGFR) in the first year post-transplant. Eligibility criteria were: ≥50 years of age or ≥30 years with at least one risk factor for vascular disease. A non-contrast-enhanced CT-scan was performed with quantification of AIC using the modified Agatston score. The association between AIC and eGFR was investigated with a linear mixed model adjusted for predefined variables. One-hundred-and-forty patients were included with a median of 31 (interquartile range 26-39) eGFR measurements per patient. No direct association between AIC and eGFR was found. We observed a significant interaction between follow-up time and ipsilateral AIC, indicating that patients with higher AIC scores had lower eGFR trajectory over time starting 100 days after transplant (p = 0.014). To conclude, severe AIC is not directly associated with lower post-transplant eGFR. The significant interaction indicates that patients with more severe AIC have a lower eGFR trajectory after 100 days in the first year post-transplant.

Propensity Score and Instrumental Variable Techniques in Observational Transplantation Studies: An Overview and Worked Example Relating to Pre-Transplant Cardiac Screening

Inferring causality from observational studies is difficult due to inherent differences in patient characteristics between treated and untreated groups. The randomised controlled trial is the gold standard study design as the random allocation of individuals to treatment and control arms should result in an equal distribution of known and unknown prognostic factors at baseline. However, it is not always ethically or practically possible to perform such a study in the field of transplantation. Propensity score and instrumental variable techniques have theoretical advantages over conventional multivariable regression methods and are increasingly being used within observational studies to reduce the risk of confounding bias. An understanding of these techniques is required to critically appraise the literature. We provide an overview of propensity score and instrumental variable techniques for transplant clinicians, describing their principles, assumptions, strengths, and weaknesses. We discuss the different patient populations included in analyses and how to interpret results. We illustrate these points using data from the Access to Transplant and Transplant Outcome Measures study examining the association between pre-transplant cardiac screening in kidney transplant recipients and post-transplant cardiac events.

Comparison of Human Urinary Exosomes Isolated via Ultracentrifugation Alone versus Ultracentrifugation Followed by SEC Column-Purification

Chronic kidney disease is a progressive, incurable condition that involves a gradual loss of kidney function. While there are no non-invasive biomarkers available to determine whether individuals are susceptible to developing chronic kidney disease, small RNAs within urinary exosomes have recently emerged as a potential candidate to use for assessing renal function. Ultracentrifugation is the gold standard for urinary exosome isolation. However, extravesicular small RNA contamination can occur when isolating exosomes from biological fluids using ultracentrifugation, which may lead to misidentifying the presence of certain small RNA species in human urinary exosomes. Therefore, we characterized human urinary exosomal preparations isolated by ultracentrifugation alone, or via ultracentrifugation followed by size exclusion chromatography (SEC) column-purification. Using nanoparticle tracking analysis, we identified SEC fractions containing robust amounts of exosome-sized particles, that we further characterized using immunoblotting. When compared to exosomal preparations isolated by ultracentrifugation only, SEC fractionated exosomal preparations showed higher levels of the exosome-positive marker CD81. Moreover, while the exosome-negative marker calnexin was undetectable in SEC fractionated exosomal preparations, we did observe calnexin detection in the exosomal preparations isolated by ultracentrifugation alone, which implies contamination in these preparations. Lastly, we imaged SEC fractionated exosomal preparations using transmission electron microscopy to confirm these preparations contained human urinary exosomes. Our results indicate that combining ultracentrifugation and SEC column-purification exosome isolation strategies is a powerful approach for collecting contaminant-free human urinary exosomes and should be considered when exosomes devoid of contamination are needed for downstream applications.

Association of cause of uremia with degree of iliac artery calcification

OBJECTIVES

We aimed to investigate whether the cause of uremia is associated with degree of calcification, and to report the proportion excluded from kidney transplantation due to iliac artery calcification.

METHOD

We enrolled 306 patients with a pre-transplant computed tomography scan who went through the comprehensive assessment program in 2013-2015. Calcification score was measured for each iliac artery segment and patient records viewed for a variety of variables. Interobserver variation was assessed for 135 paired observations.

RESULTS

The patients' mean age was 55.5 years. Of the 306 patients, 133 did not undergo transplantation, and for 21 of these, heavy calcification was the primary explanation for this. External iliac artery calcification was positively associated with male sex, age, systolic blood pressure, diabetes and cardiovascular disease, and differed significantly among the causes of uremia subgroups; the least calcification was seen in patients with autoimmune causes, and the highest in those with diabetic causes. Similarly, the proportion of patients who underwent renal transplantation differed significantly with regard to causes of uremia (ranging from 72.3% for autoimmune disease to 40.6% for diabetic nephropathy).

CONCLUSION

The degree of iliac artery calcification differs according to the cause of uremia and influences the likelihood of receiving a kidney transplantation.

Risk of post-transplant cardiovascular events in kidney transplant recipients with preexisting aortoiliac stenosis

Prediction of the risk of cardiovascular events (CVE's) is important to optimize outcomes after kidney transplantation. Aortoiliac stenosis is frequently observed during pre‐transplant screening. We hypothesized that these patients are at higher risk of post‐transplant CVE's due to the joint underlying atherosclerotic disease. Therefore, we aimed to assess whether aortoiliac stenosis was associated with post‐transplant CVE's. This retrospective, single‐center cohort study included adult kidney transplant recipients, transplanted between 2000 and 2016, with contrast‐enhanced imaging available. Aortoiliac stenosis was classified according to the Trans‐Atlantic Inter‐Society Consensus (TASC) II classification and was defined as significant in case of ≥50% lumen narrowing. The primary outcome was CVE‐free survival. Eighty‐nine of 367 patients had significant aortoiliac stenosis and were found to have worse CVE‐free survival (median CVE‐free survival: stenosis 4.5 years (95% confidence interval (CI) 2.8–6.2), controls 8.9 years (95% CI 6.8–11.0); log‐rank test P < .001). TASC II C and D lesions were independent risk factors for a post‐transplant CVE with a hazard ratio of 2.15 (95% CI 1.05–4.38) and 6.56 (95% CI 2.74–15.70), respectively. Thus, kidney transplant recipients with TASC II C and D aortoiliac stenosis require extensive cardiovascular risk management pre‐, peri,‐ and post‐transplantation.

Non-medical barriers in access to early steps of kidney transplantation in the United States - A scoping review

BACKGROUND

In the United States (US), barriers in access to later steps in the kidney transplantation process (i.e. waitlisting) have been well documented. Barriers in access to earlier steps (i.e. referral and evaluation) are less well described due to the lack of national surveillance data. In this review, we summarize the available literature on non-medical barriers in access to kidney transplant referral and evaluation.

METHODS

Following PRISMA guidelines, we conducted a scoping review of the literature through June 3, 2021. We included all studies (quantitative and qualitative) reporting on barriers to kidney transplant referral and evaluation in the US published from 1990 onwards in English and among adult end-stage kidney disease (ESKD) patients (PROSPERO registration number: CRD42014015027). We narratively synthesized results across studies.

RESULTS

We retrieved information from 33 studies published from 1990 to 2021 (reporting data between 1990 and 2018). Most studies (n = 28, 85%) described barriers among patient populations, three (9%) among provider populations, and two (6%) included both patients and providers. Key barriers were identified across multiple levels and included patient- (e.g. demographic, socioeconomic, sociocultural, and knowledge), provider- (e.g. miscommunication, staff availability, provider perceptions and attitudes), and system- (e.g. geography, distance to care, healthcare logistics) level factors.

CONCLUSIONS

A multi-pronged approach (e.g. targeted and systemwide interventions, and policy change) implemented at multiple levels of the healthcare system will be necessary to reduce identified barriers in access to early kidney transplant steps. Collection of national surveillance data on these early kidney transplant steps is also needed to enhance our understanding of barriers to referral and evaluation.

Non-invasive cardiac stress studies may not offer significant benefit in pre-kidney transplant evaluation: A retrospective cohort study

Background

Screening with cardiac non-invasive stress studies (NISS) prior to listing for kidney transplantation can help in identifying treatable coronary disease and is considered an integral part of pre-kidney transplant evaluation. However, few studies assessed their effectiveness in all patients evaluated for transplantation in clinical practice. To evaluate the role of NISS in pre-kidney transplant evaluation we analyzed their impact prior to waitlisting in 1053 adult CKD-5 patients consecutively evaluated in Greater Manchester, UK during a 6-year period.

Methods

918 waitlisted patients were grouped based on presence or absence of Diabetes or Cardio-Vascular Disease (CVD): Group-1 (255 DM-/CVD-/NISS-), Group-2 (368 DM-/CVD-/NISS+) and Group-3 (295 with DM or CVD).

Results

Group-2 patients had longer ‘time-to-listing’ (5.5months in Group-1 vs 6.9months in ‘Normal-NISS’ vs 9.9months in ‘Abnormal-NISS’, p<0.01) but none with ‘Abnormal-NISS’ needed coronary revascularization before listing. NISS was followed by revascularization in 8 Group-3 patients (3%). In multi-variate analyses, there was no association of NISS on death or MACE in listed patients. During follow up, Transplantation was the most significant factor associated with improved outcomes in all subgroups (HR:0.97, p<0.001). 135 patients were considered unsuitable for waitlisting, with NISS influencing management in 11 of these patients (8%).

Conclusions

Pre-kidney transplant evaluation with NISS influenced clinical management in 19 of 1053 (2%) patients. Screening with NISS added limited benefit but contributes to significant delays in listing and adding resource implications. Further studies are needed to assess clinical and cost effectiveness of NISS in pretransplant evaluation to optimize outcomes and resources.

Impact of Aortoiliac Stenosis on Graft and Patient Survival in Kidney Transplant Recipients Using the TASC II Classification

BACKGROUND

Patients with end-stage renal disease and aortoiliac stenosis are often considered ineligible for kidney transplantation, although kidney transplantation has been acknowledged as the best therapy for end-stage renal disease. The clinical outcomes of kidney transplantation in patients with aortoiliac stenosis are not well-studied. This study aimed to assess the impact of aortoiliac stenosis on graft and patient survival.

METHODS

This retrospective, single-center study included kidney transplant recipients transplanted between January 1, 2000, and December 31, 2016, who received contrast-enhanced imaging. Patients with aortoiliac stenosis were classified using the Trans-Atlantic Inter-Society Consensus (TASC) II classification and categorized as having TASC II A/B lesions or having TASC II C/D lesions. Patients without aortoiliac stenosis were functioning as controls.

RESULTS

A total number of 374 patients was included in this study (n = 88 with TASC II lesions, n = 286 as controls). Death-censored graft survival was similar to the controls. Patient and uncensored graft survival was decreased in patients with TASC II C/D lesions (log-rank test P < 0.001). Patients with TASC II C/D lesions had a higher risk of 90-day mortality (hazard ratio, 3.96; 95% confidence interval, 1.12-14.04). In multivariable analysis, having a TASC II C/D lesion was an independent risk factor for mortality (hazard ratio, 3.25; 95% confidence interval, 1.87-5.67; P < 0.001). Having any TASC II lesion was not a risk factor for graft loss (overall P = 0.282).

CONCLUSIONS

Kidney transplantation in patients with TASC II A/B is feasible and safe without increased risk of perioperative mortality. TASC II C/D decreases patient survival. Death-censored graft survival is unaffected.

An opt-out model for kidney transplant referral: The time has come

Disparities that affect equity in access to kidney transplantation for patients with kidney failure have been well described. Many robust clinical trials have tested the effectiveness of interventions to reduce disparities and equilibrate access to kidney transplantation. Moreover, policy changes have been enacted to achieve the same aims. Despite these efforts, rates of kidney transplant waitlisting within the first year of end-stage kidney disease have remained unchanged over the past 2 decades, while incident rates of end-stage kidney disease have climbed. Because prior interventions have not durably increased transplant access, disruptive change is clearly needed. The Advancing American Kidney Health Executive Order sets bold goals to transform kidney care for patients and caregivers. In this spirit, we discuss an Opt-Out for Transplant Referral Model as a compelling solution to improve equity in access to kidney transplantation.

The prognosis of kidney transplant recipients with aorto-iliac calcification: a systematic review and meta-analysis

The prognosis of kidney transplant recipients (KTR) with vascular calcification (VC) in the aorto-iliac arteries is unclear. We performed a systematic review and meta-analysis to investigate their survival outcomes. Studies from January 1st, 2000 until March 5th, 2019 were included. Outcomes for meta-analysis were patient survival, (death-censored) graft survival and delayed graft function (DGF). Twenty-one studies were identified, eight provided data for meta-analysis. KTR with VC had a significantly increased mortality risk [1-year: risk ratio (RR) 2.19 (1.39-3.44), 5-year: RR 2.28 (1.86-2.79)]. The risk of 1-year graft loss was three times higher in recipients with VC [RR 3.15 (1.30-7.64)]. The risk of graft loss censored for death [1-year: RR 2.26 (0.58-2.73), 3-year: RR 2.19 (0.49-9.82)] and the risk of DGF (RR 1.24, 95% CI 0.98-1.58) were not statistically different. The quality of the evidence was rated as very low. To conclude, the presence of VC was associated with an increased mortality risk and risk of graft loss. In this small sample size, no statistical significant association between VC and DGF or risk of death-censored graft loss could be demonstrated. For interpretation of the outcomes, the quality and sample size of the evidence should be taken into consideration.

Referral for Kidney Transplantation in Canadian Provinces

BACKGROUND

Patient referral to a transplant facility, a prerequisite for dialysis-treated patients to access kidney transplantation in Canada, is a subjective process that is not recorded in national dialysis or transplant registries. Patients who may benefit from transplant may not be referred.

METHODS

In this observational study, we prospectively identified referrals for kidney transplant in adult patients between June 2010 and May 2013 in 12 transplant centers, and linked these data to information on incident dialysis patients in a national registry.

RESULTS

Among 13,184 patients initiating chronic dialysis, the cumulative incidence of referral for transplant was 17.3%, 24.0%, and 26.8% at 1, 2, and 3 years after dialysis initiation, respectively; the rate of transplant referral was 15.8 per 100 patient-years (95% confidence interval, 15.1 to 16.4). Transplant referral varied more than three-fold between provinces, but it was not associated with the rate of deceased organ donation or median waiting time for transplant in individual provinces. In a multivariable model, factors associated with a lower likelihood of referral included older patient age, female sex, diabetes-related ESKD, higher comorbid disease burden, longer durations (>12.0 months) of predialysis care, and receiving dialysis at a location >100 km from a transplant center. Median household income and non-Caucasian race were not associated with a lower likelihood of referral.

CONCLUSIONS

Referral rates for transplantation varied widely between Canadian provinces but were not lower among patients of non-Caucasian race or with lower socioeconomic status. Standardization of transplantation referral practices and ongoing national reporting of referral may decrease disparities in patient access to kidney transplant.

Infrainguinal bypass surgery outcomes are worse in hemodialysis patients compared with patients with renal transplants

OBJECTIVE

Studies of infrainguinal bypass surgery (IBS) in patients with end-stage renal disease have focused on hemodialysis (HD) patients. Little is known of the applicability of their outcomes to patients with renal transplants (RTs). In this study, we sought to compare perioperative and long-term outcomes of IBS in a large population-based cohort of HD and RT patients.

METHODS

A retrospective review of all HD and RT patients who underwent IBS between January 2007 and December 2011 in the U.S. Renal Data System was performed. Univariable, Kaplan-Meier, multivariable logistic, and Cox regression analyses were employed to evaluate 30-day postoperative (graft failure, limb loss, conduit infection, death) and long-term (primary patency [PP], primary assisted patency [PAP], secondary patency [SP], limb salvage, mortality) outcomes.

RESULTS

There were 10,787 IBSs performed in 9739 (90%) HD patients and 1048 (10%) RT patients who presented predominantly with critical limb ischemia (72%). Bypass configurations were femoral-popliteal (48%), femoral-tibial (34%), and popliteal-tibial (18%). Comparing HD vs RT patients, PP, PAP, and SP were 18% vs 33%, 23% vs 38%, and 30% vs 48%, respectively, at 5 years among autogenous conduit recipients (all P < .001) and 20% vs 28% (P = .02), 23% vs 31% (P = .02), and 33% vs 53% (P < .001) among prosthetic conduit recipients. Limb salvage and patient survival were 39% vs 56% and 19% vs 48%, respectively, at 5 years (all P < .001). Risk-adjusted analyses demonstrated higher PP (adjusted hazard ratio [aHR], 1.32; 95% confidence interval [CI], 1.20-1.45; P < .001), PAP (aHR, 1.32; 95% CI, 1.19-1.45; P < .001), SP (aHR, 1.47; 95% CI, 1.31-1.65; P < .001), limb salvage (aHR, 1.48; 95% CI, 1.30-1.67; P < .001), and patient survival (aHR, 2.42; 95% CI, 2.17-2.71; P < .001) for RT compared with HD patients.

CONCLUSIONS

The HD-dependent state is associated with elevated bypass and patient-level risks after IBS compared with patients with RTs. These results show that the benefits of renal transplantation likely extend to infrainguinal bypass-specific outcomes. The estimates of risk reported herein should inform the patient's and provider's expectations at the point of care.

Type 2 diabetic patients on renal replacement therapy: Probability to receive renal transplantation and survival after transplantation

Background

Type 2 diabetic (T2DM) patients on renal replacement therapy (RRT) seldom receive a kidney transplant, which is partly due to age and comorbidities. Adjusting for case mix, we investigated whether T2DM patients have equal opportunity for renal transplantation compared to other patients on dialysis, and whether survival after transplantation is comparable.

Methods

Patients who entered RRT in Finland in 2000–2010 (n = 5419) were identified from the Finnish Registry for Kidney Diseases and followed until the end of 2012. Of these, 20% had T2DM, 14% type 1 diabetes (T1DM) and 66% other than diabetes as the cause of ESRD. Uni-/multivariate survival analysis techniques were employed to assess the probability of kidney transplantation after the start of dialysis and survival after transplantation.

Results

T2DM patients had a relative probability of renal transplantation of 0.18 (95% CI 0.15–0.22, P<0.001) compared to T1DM patients: this increased to 0.51 (95% CI 0.36–0.72, P<0.001) after adjustment for case mix (age, gender, laboratory values and comorbidities). When T2DM patients were compared to non-diabetic patients, the corresponding relative probabilities were 0.25 (95% CI 0.20–0.30, P<0.001) and 0.59 (95% CI 0.43–0.83, P = 0.002). After renal transplantation when adjusted for age and gender, relative risk of death was 1.25 (95% CI 0.64–2.44, P = 0.518) for T1DM patients and 0.72 (0.43–1.22, P = 0.227) for other patients compared to T2DM patients.

Conclusions

T2DM patients had a considerably lower probability of receiving a kidney transplant, which could not be fully explained by differences in the patient characteristics. Survival within 5 years after transplantation is comparably good in T2DM patients.

Peripheral arterial disease preoperatively may predict graft failure and mortality in kidney transplant recipients

Patients with end-stage renal disease undergoing kidney transplant often have diffuse atherosclerosis and high cardiovascular morbidity and mortality rates. We analyzed the correlation of peripheral arterial disease (PAD), here quantified by an abnormal ankle–brachial index (ABI) measured within the 5 years prior to kidney transplant, with graft failure and mortality rates (primary end points) after adjusting for known cardiovascular risk factors (age, sex, smoking history, hypertension, diabetes, stroke, known coronary artery disease or heart failure, years of dialysis). Of 1055 patients in our transplant population, 819 had arterial studies within the 5 years prior to transplant. Secondary end points included myocardial infarction; cerebrovascular accident; and limb ischemia, gangrene, or amputation. Low ABI was an independent and significant predictor of organ failure (OR, 2.77 (95% CI, 1.68–4.58), p<0.001), secondary end points (HR, 1.39 (95% CI, 0.97–1.99), p<0.076), and death (HR, 1.84 (95% CI, 1.26–2.68), p=0.002). PAD was common in this population: of 819 kidney transplant recipients, 46% had PAD. Low ABI was associated with a threefold greater risk of graft failure, a twofold greater risk of death after transplant, and a threefold greater risk of secondary end points. Screening for PAD is important in this patient population because of the potential impact on long-term outcomes.

Kidney transplant referral practices in southeastern dialysis units

BACKGROUND

The Southeastern Kidney Transplant Coalition was created in 2010 to improve kidney transplant (KTx) rates in Georgia, North Carolina, and South Carolina. To identify dialysis staff-reported barriers to transplant, the Coalition developed a survey of dialysis providers in the region.

METHODS

All dialysis units in the ESRD Network (n = 586) were sent a survey to be completed by the professional responsible for helping patients get transplants.

RESULTS

One staff member at almost all (n = 546) of the dialysis units in Network 6 completed the survey (93% response rate). Almost all respondents reported being very comfortable (51.47%) or comfortable (46.89%) discussing the KTx process with patients. Just over half (56%) of facilities reported discussing KTx as a treatment option with patients on an annual basis. Fewer than one quarter of respondents (19%) perceived that more than 50% of their patients were interested in kidney transplant, and most of the staff surveyed (68%) reported that <25% of their dialysis patients completed the evaluation process and been wait-listed for a kidney transplant.

CONCLUSION

The survey results provide insight into KTx referral practices in southeastern dialysis units that may be contributing to low KTx rates in this region.

Variation in Dialysis Facility Referral for Kidney Transplantation Among Patients With End-Stage Renal Disease in Georgia

IMPORTANCE

Dialysis facilities in the United States are required to educate patients with end-stage renal disease about all treatment options, including kidney transplantation. Patients receiving dialysis typically require a referral for kidney transplant evaluation at a transplant center from a dialysis facility to start the transplantation process, but the proportion of patients referred for transplantation is unknown.

OBJECTIVE

To describe variation in dialysis facility-level referral for kidney transplant evaluation and factors associated with referral among patients initiating dialysis in Georgia, the US state with the lowest kidney transplantation rates.

DESIGN, SETTING, AND PARTICIPANTS

Examination of United States Renal Data System data from a cohort of 15,279 incident, adult (18-69 years) patients with end-stage renal disease from 308 Georgia dialysis facilities from January 2005 to September 2011, followed up through September 2012, linked to kidney transplant referral data collected from adult transplant centers in Georgia in the same period.

MAIN OUTCOMES AND MEASURES

Referral for kidney transplant evaluation within 1 year of starting dialysis at any of the 3 Georgia transplant centers was the primary outcome; placement on the deceased donor waiting list was also examined.

RESULTS

The median within-facility percentage of patients referred within 1 year of starting dialysis was 24.4% (interquartile range, 16.7%-33.3%) and varied from 0% to 75.0%. Facilities in the lowest tertile of referral (<19.2%) were more likely to treat patients living in high-poverty neighborhoods (absolute difference, 21.8% [95% CI, 14.1%-29.4%]), had a higher patient to social worker ratio (difference, 22.5 [95% CI, 9.7-35.2]), and were more likely nonprofit (difference, 17.6% [95% CI, 7.7%-27.4%]) compared with facilities in the highest tertile of referral (>31.3%). In multivariable, multilevel analyses, factors associated with lower referral for transplantation, such as older age, white race, and nonprofit facility status, were not always consistent with the factors associated with lower waitlisting.

CONCLUSIONS AND RELEVANCE

In Georgia overall, a limited proportion of patients treated with dialysis were referred for kidney transplant evaluation between 2005 and 2011, but there was substantial variability in referral among facilities. Variables associated with referral were not always associated with waitlisting, suggesting that different factors may account for disparities in referral.

Kidney transplant access in the Southeast: view from the bottom

The Southeastern region of the United States has the highest burden of end-stage renal disease (ESRD) but the lowest rates of kidney transplantation in the nation. There are many patient-, dialysis facility-, ESRD Network- and health system-level barriers that contribute to this regional disparity. Compared to the rest of the nation, the Southeast has a larger population of African-Americans and higher poverty, as well as more prevalent ESRD risk factors including hypertension, obesity and diabetes. Dialysis facilities--where ESRD patients receive the majority of their healthcare--play an important role in transplant access. Identifying characteristics of individual dialysis units with low rates of kidney transplantation, such as understaffing or for-profit status, can help identify targets for quality improvement initiatives. Geographic differences across the country can identify opportunities to increase funding for healthcare resources in proportion to patient and disease burden. Focusing interventions among dialysis facilities with the lowest transplant rates within the Southeast, such as provider and patient education, has the potential to increase referrals for kidney transplantation, leading to higher rates of kidney transplants in this region. Referral for transplantation should be measured on a national level to monitor disparities in early access to transplantation. Transplant centers have an obligation to assist underserved populations in ensuring equity in access to services. Policies that improve access to care for patients, such as the Affordable Care Act and Medicaid expansion, are particularly important for Southern states and may alleviate geographic disparities.

Access to renal transplantation in the diabetic population-effect of comorbidities and body mass index

BACKGROUND

In this study, we hypothesized that higher level of comorbidity and greater body mass index (BMI) may mediate the association between diabetes and access to transplantation.

METHODS

We used data from the United States Renal Data System (01/01/2000-24/09/2007; n = 619,151). We analyzed two outcomes using Cox model: (i) time to being placed on the waiting list or transplantation without being listed and (ii) time to transplantation after being listed. Two primary Cox models were developed based on different levels of adjustment.

RESULTS

In Cox models adjusted for a priori defined potential confounders, history of diabetes was associated with reduced transplant access (compared with non-diabetic population) - both for wait-listing/transplant without being listed (hazard ratio, HR = 0.80, p < 0.001) and for transplant after being listed (HR = 0.72, p < 0.001). In Cox models adjusted for BMI and comorbidity index along with the potential confounders, history of diabetes was associated with shorter time to wait-listing or transplantation without being listed (HR = 1.07, p < 0.001), and there was no significant difference in time to transplantation after being listed (HR = 1.01, p = 0.42).

CONCLUSION

We demonstrated that higher level of comorbidity and greater BMI mediate the association between diabetes and reduced access to transplantation.