First-time Kidney Transplant Recipients Research Articles

#1617 Effect of pre-renal transplant anticoagulation and antiplatelet therapy on post-transplant outcomes: a retrospective single-center study

Abstract Background and Aims The management of anticoagulation and antiplatelet therapy in stage V chronic kidney disease (CKD) patients undergoing renal transplantation is controversial. While some centers utilize reversal agents or procoagulants before surgery, other experiences suggest that renal transplantation can be safely performed without discontinuation of such treatments. The aim of this study is to assess the incidence of hemorrhagic and thrombotic complications within the first 72 hours post-transplant in anticoagulated or antiplatelet-treated patients compared to those without these treatments (control group). Method Retrospective cohort study of patients undergoing renal transplantation at our center between June 2018 and February 2022, with a 6-month post-transplant follow-up. Epidemiological, clinical, and analytical data were collected. Results 147 patients, predominantly male (60.3%). 8.1% were anticoagulated, and 16.3% were on antiplatelet therapy. Antiplatelet-treated patients were older (63 years) with a higher prevalence of cardiovascular disease history (54.2%). Anticoagulated patients showed a higher frequency of diabetes (50%) and atrial fibrillation (16.7%). The time on dialysis was also longer in anticoagulated or antiplatelet-treated patients (39.5 and 39 vs 33 months). 80.9% were first-time kidney transplant recipients from brain-dead donors, although the donor's age was lower in the control group. Ischemia time was similar in all three groups with no statistically significant differences. However, the length of hospital stay was longer for those receiving anticoagulation or antiplatelet therapy compared to the control group. 58.3% of anticoagulated patients received warfarin (pre-surgery INR of 1.5). In 50% of cases, reversal was performed using coagulation factors, vitamin K, fresh frozen plasma, or combinations of these therapies. 83.3% of antiplatelet-treated patients received aspirin, mainly for secondary prevention (54.2%), and only 8.3% received reversal therapy through plasma administration. The incidence of hemorrhagic and thrombotic complications was low (<5%) and did not significantly differ between anticoagulated or antiplatelet-treated patients and those without these treatments, although transfusion rates were higher in the anticoagulation group (75%) compared to 51.4% in the control group and 62.5% in antiplatelet-treated patients. Conclusion There are no significant differences regarding hemorrhagic and thrombotic complications between anticoagulated or antiplatelet-treated patients and those without these treatments, while the percentage of blood transfusions and hospital stay was higher in anticoagulated or antiplatelet-treated patients.

Incomplete reporting of clinically significant acute rejection episodes in the national kidney transplant registry

Administrative claims data could provide a unique opportunity to identify acute rejection (AR) events using specific antirejection medications and to validate rejected data reported to the Organ Procurement and Transplantation Network. This retrospective cohort study examined differences in registry-reported events and those identified using claims data among adult kidney transplant recipients from 2012 to 2017 using Standard Analysis Files from the US Renal Data System. Rejection rates, survival estimates, and center-level differences were assessed using each approach. Among 45 880 first-time kidney transplant recipients, we identified 3841 AR events within 12 months of transplant reported by centers in the registry; claims data yielded 2945 events. Of all events occurring within 12 months of transplant, 48.5% were reported using registry only, 32.9% were identified using claims only, and 18.6% were identified using both approaches. A 3-year death-censored graft survival probability was 90.0%, 88.4%, and 81.2% (P < .001) for ARs identified using registry only, claims data only, and both approaches, respectively. The large discordance between registry-reported and claims-based events suggests incomplete and potentially inaccurate reporting of events in the Organ Procurement Transplant Network registry. These findings have important implications for analyses that use AR data and underscore the need for improved capture of clinically meaningful events.

Long-term cardiovascular events, graft failure, and mortality in kidney transplant recipients

BackgroundKidney transplant recipients are at increased risks of cardiovascular events, but contemporary risk estimates are sparse. Using the Danish nationwide administrative databases, we quantified 1- and 5-year risks of cardiovascular disease and kidney failure among all first-time kidney transplant recipients (2005-2018) and age- and sex-matched controls (1:10 ratio). MethodsCumulative 1- and 5-year incidence of cardiovascular events (myocardial infarction, stroke, or heart failure), kidney failure (re-transplantation or need for dialysis >30 days post-transplant), and mortality following transplantation were calculated until maximally Dec 31, 2018. ResultsA total of 2,565 kidney transplant recipients (median age 50.5 [25-75th percentile 40.2-60.7] years, 37 % females) and 25,650 controls were included. 1-year cumulative incidence of myocardial infarction, stroke, or heart failure was 2.6 % (95 % confidence interval 1.9 %-3.2 %) among kidney transplant recipients versus 0.5 % (0.4 %-0.5 %) in controls. Cumulative 5-year risk estimates for the same endpoints were 8.3 % (7.1 %-9.5 %) for the transplant patients, and 2.6 % (2.3 %-2.8 %) among controls, respectively. For the kidney transplant cohort, cumulative mortality was 2.2 % (1.7 %-2.8 %) and 10.3 % (9.0 %-11.6 %) at 1- and 5 years, respectively, versus 0.5 % (0.4 %-0.6 %) and 3.0 % (2.7 %-3.2 %) for controls. The cumulative incidence of dialysis and re-transplantation was 6.1 % (5.2 %-7.1 %) at 1 year and 16.3 % (14.7 %-17.9 %) at 5 years, respectively. ConclusionsDespite the benefits of transplantation, kidney transplant recipients continue to have significant long-term cardiovascular disease, end-stage kidney disease, and mortality risks even with contemporary medical management. Better cardiovascular preventive strategies are warranted to improve prognosis in this segment of patients.

Association of Postoperative Delirium With Incident Dementia and Graft Outcomes Among Kidney Transplant Recipients.

Kidney transplant (KT) recipients have numerous risk factors for delirium, including those shared with the general surgical population (eg, age and major surgery) and transplant-specific factors (eg, neurotoxic immunosuppression medications). Evidence has linked delirium to long-term dementia risk in older adults undergoing major surgery. We sought to characterize dementia risk associated with post-KT delirium. Using the United States Renal Data System datasets, we identified 35 800 adult first-time KT recipients ≥55 y. We evaluated risk factors for delirium using logistic regression. We evaluated the association between delirium and incident dementia (overall and by subtype: Alzheimer's, vascular, and other/mixed-type), graft loss, and death using Fine and Gray's subhazards models and Cox regression. During the KT hospitalization, 0.9% of recipients were diagnosed with delirium. Delirium risk factors included age (OR = 1.40, 95% CI, 1.28-1.52) and diabetes (OR = 1.38, 95% CI, 1.10-1.73). Delirium was associated with higher risk of death-censored graft loss (aHR = 1.52, 95% CI, 1.12-2.05) and all-cause mortality (aHR = 1.53, 95% CI, 1.25-1.89) at 5 y post-KT. Delirium was also associated with higher risk of dementia (adjusted subhazard ratio [aSHR] = 4.59, 95% CI, 3.48-6.06), particularly vascular dementia (aSHR = 2.51, 95% CI, 1.01-6.25) and other/mixed-type dementia (aSHR = 5.58, 95% CI, 4.24-7.62) subtypes. The risk of all-type dementia associated with delirium was higher for younger recipients aged between 55 and 64 y ( Pinteraction = 0.01). Delirium is a strong risk factor for subsequent diagnosis of dementia among KT recipients, particularly those aged between 55 and 64 y at the time of transplant. Patients experiencing posttransplant delirium might benefit from early interventions to enhance cognitive health and surveillance for cognitive impairment to enable early referral for dementia care.

Differences between Kidney Transplant Recipients from Deceased Donors with Diabetes Mellitus as Identified by Machine Learning Consensus Clustering.

Clinical outcomes of deceased donor kidney transplants coming from diabetic donors currently remain inconsistent, possibly due to high heterogeneities in this population. Our study aimed to cluster recipients of diabetic deceased donor kidney transplants using an unsupervised machine learning approach in order to identify subgroups with high risk of inferior outcomes and potential variables associated with these outcomes. Consensus cluster analysis was performed based on recipient-, donor-, and transplant-related characteristics in 7876 recipients of diabetic deceased donor kidney transplants from 2010 to 2019 in the OPTN/UNOS database. We determined the important characteristics of each assigned cluster and compared the post-transplant outcomes between the clusters. Consensus cluster analysis identified three clinically distinct clusters. Recipients in cluster 1 (n = 2903) were characterized by oldest age (64 ± 8 years), highest rate of comorbid diabetes mellitus (55%). They were more likely to receive kidney allografts from donors that were older (58 ± 6.3 years), had hypertension (89%), met expanded criteria donor (ECD) status (78%), had a high rate of cerebrovascular death (63%), and carried a high kidney donor profile index (KDPI). Recipients in cluster 2 (n = 687) were younger (49 ± 13 years) and all were re-transplant patients with higher panel reactive antibodies (PRA) (88 [IQR 46, 98]) who received kidneys from younger (44 ± 11 years), non-ECD deceased donors (88%) with low numbers of HLA mismatch (4 [IQR 2, 5]). The cluster 3 cohort was characterized by first-time kidney transplant recipients (100%) who received kidney allografts from younger (42 ± 11 years), non-ECD deceased donors (98%). Compared to cluster 3, cluster 1 had higher incidence of primary non-function, delayed graft function, patient death and death-censored graft failure, whereas cluster 2 had higher incidence of delayed graft function and death-censored graft failure but comparable primary non-function and patient death. An unsupervised machine learning approach characterized diabetic donor kidney transplant patients into three clinically distinct clusters with differing outcomes. Our data highlight opportunities to improve utilization of high KDPI kidneys coming from diabetic donors in recipients with survival-limiting comorbidities such as those observed in cluster 1.

Association of Pretransplant Coronary Heart Disease Testing With Early Kidney Transplant Outcomes

Testing for coronary heart disease (CHD) in asymptomatic kidney transplant candidates before transplant is widespread and endorsed by various professional societies, but its association with perioperative outcomes is unclear. To estimate the association of pretransplant CHD testing with rates of death and myocardial infarction (MI). This retrospective cohort study included all adult, first-time kidney transplant recipients from January 2000 through December 2014 in the US Renal Data System with at least 1 year of Medicare enrollment before and after transplant. An instrumental variable (IV) analysis was used, with the program-level CHD testing rate in the year of the transplant as the IV. Analyses were stratified by study period, as the rate of CHD testing varied over time. A combination of US Renal Data System variables and Medicare claims was used to ascertain exposure, IV, covariates, and outcomes. Receipt of nonurgent invasive or noninvasive CHD testing during the 12 months preceding kidney transplant. The primary outcome was a composite of death or acute MI within 30 days of after kidney transplant. The cohort comprised 79 334 adult, first-time kidney transplant recipients (30 147 women [38%]; 25 387 [21%] Black and 48 394 [61%] White individuals; mean [SD] age of 56 [14] years during 2012 to 2014). The primary outcome occurred in 4604 patients (244 [5.3%]; 120 [2.6%] death, 134 [2.9%] acute MI). During the most recent study period (2012-2014), the CHD testing rate was 56% in patients in the most test-intensive transplant programs (fifth IV quintile) and 24% in patients at the least test-intensive transplant program (first IV quintile, P < .001); this pattern was similar across other study periods. In the main IV analysis, compared with no testing, CHD testing was not associated with a change in the rate of primary outcome (rate difference, 1.9%; 95% CI, 0%-3.5%). The results were similar across study periods, except for 2000 to 2003, during which CHD testing was associated with a higher event rate (rate difference, 6.8%; 95% CI, 1.8%-12.0%). The results of this cohort study suggest that pretransplant CHD testing was not associated with a reduction in early posttransplant death or acute MI. The study findings potentially challenge the ubiquity of CHD testing before kidney transplant and should be confirmed in interventional studies.

210. Neutropenia and Associated Infectious Complications Among Kidney Transplant Recipients Receiving Valganciclovir Prophylaxis in the United States: An Administrative Claims Database Study

Abstract Background Valganciclovir (VGCV) prophylaxis is commonly utilized to prevent cytomegalovirus (CMV) infection among high (D+/R-) and intermediate (R+) risk kidney transplant recipients (KTRs). Due to the myelosuppressive effects of VGCV, KTRs may be at an increased risk of opportunistic infections (OIs) resulting in interruptions to VGCV therapy. Therefore, we aimed to quantify the clinical burden of neutropenia among adult KTRs receiving VGCV prophylaxis. Methods A retrospective cohort design was utilized to identify adult KTRs who received VGCV prophylaxis using the IBM MarketScan Commercial and Medicare Supplemental claims databases. First-time KTRs between 1/1/2012 - 12/31/2018 with 1 year of continuous pharmacy and medical coverage before (baseline period) and after (follow-up period) were included. KTRs with a History of other solid organ transplantation were excluded. Fills of ≥ 1 prescription of VGCV (either 450 mg or 900 mg/day) within 30 days of the kidney transplant (KT). Neutropenia events were identified as either ≥ 1 inpatient, or ≥ 2 outpatient ICD-9/ICD-10 diagnoses codes within 14 days. Results Of the 4,965 adults KTRs with baseline and follow-up enrollment, 3,258 (66%) used VGCV prophylaxis. 311/3256 (9.5%) developed neutropenia within 1-year post KT. Baseline characteristics were similar between those with and without neutropenia (table 1). The majority received the following pre-transplant immunosuppression: tacrolimus (78.9%), mycophenolate mofetil (62.8%) and steroids (prednisone, 79.3%, methylprednisolone 10.6%). KTRs with neutropenia had a nearly two-fold increase in the development of CMV infection compared to those without neutropenia. In addition, KTRs with neutropenia had significantly higher rate of bacterial or fungal infections compared to those without neutropenia (Table 2). Interruptions in VGCV prophylaxis (gap &amp;gt;15 days) were more common in KTRs with neutropenia (P&amp;lt; 0.001). Conclusion Our findings showed that neutropenia was associated viral, bacterial, and fungal OIs among adults KT receiving VGCV prophylaxis. The findings highlight the needs for interventions to reduce neutropenia and its associated OIs. These results suggest that clinical management steps to reduce rates of neutropenia among KT recipients may warrant further study. Disclosures Vladimir Turzhitsky, PhD, Merck &amp; Co., Inc.,: Employee|Merck &amp; Co., Inc.,: Stocks/Bonds Amit D. Raval, PhD, Merck and Co., Inc.: Employee of Merck|Merck and Co., Inc.: Stocks/Bonds Pamela Moise, PharmD, Merck &amp; Co., Inc: Employee &amp; Shareholder Sanjay Merchant, PhD, Merck &amp; Co., Inc.: Stocks/Bonds.

Effect of pretransplant dialysis vintage on clinical outcomes in deceased donor kidney transplant

The waiting time for deceased donor kidney transplants (DDKT) is increasing. We evaluated DDKT prognosis according to the pretransplant dialysis vintage. A total of 4117 first-time kidney transplant recipients were enrolled from a prospective nationwide cohort in Korea. DDKT recipients were divided into tertiles according to pretransplant dialysis duration. Graft failure, mortality, and composite were compared between DDKT and living donor kidney transplant (LDKT) recipients. Pretransplant dialysis vintage was longer annually in DDKT recipients. In the subdistribution of the hazard model for the competing risk, the first tertile did not show an increased risk of graft failure compared with LDKT recipients; however, the second and third tertile groups had an increased risk of graft failure compared to LDKT recipients (adjusted hazard ratio [aHR] 3.59; 95% confidence interval [CI] 1.69–7.63; P < 0.001; aHR 2.37; 95% CI 1.06–5.33; P = 0.037). All DDKT groups showed a significantly higher risk of patient death than LDKT, with the highest risk in the third tertile group (aHR 11.12; 95% CI 4.94–25.00; P < 0.001). A longer pretransplant dialysis period was associated with a higher risk of the composite of patient death and graft failure in DDKT recipients. DDKT after a short period of dialysis had non-inferior results on graft survival compared with LDKT.

Outcome of Renal Transplantation in Children Given Rabbit Anti-Thymocyte Globulin (rATG) as Induction Therapy

BackgroundInduction immunosuppressive therapy is used to prevent rejection and maintain allograft function in transplantation. Rabbit antithymocyte globulin (rATG), a T-cell depleting antibody, is the most commonly used induction agent for kidney transplantation. To date there is still limited data on outcomes of pediatric kidney transplants with rATG as induction therapy. MethodsRetrospective single-center study of first-time kidney transplant recipients ≤18 years old who received rATG induction between 2005 and 2019 at the National Kidney and Transplant Institute. Data were collected up to 1 year post transplant. ResultsEleven patients were included in the study. They received rATG at 1.5 mg/kg/dose (±0.3 mg/kg/dose) once a day for 3 days. Patient survival was 100% at 6 months, and 90.9% at 1 year. Graft survival was 90.9% at 6 months, and 81.8% at 1 year. Four patients (36.4%) had a glomerular filtration rate of <60 at 1 year. One died of sepsis at 7 months. One patient (9.1%) had acute allograft rejection with recurrence of disease, C3 glomerulopathy, on day 13. A total of 3 patients (27.3%) developed leukopenia and 4 patients (36.4%) developed thrombocytopenia. The majority were anemic at baseline (9.7 mg/dL), and a significant increase in the mean hemoglobin was seen at 4 weeks (11.6 mg/dL) to 1 year (13 mg/dL). Incidence of recurrent infections was 9.1% (with culture growth) and 36.4% (no culture growth). Hypertension remained unchanged before and after transplant. ConclusionsInduction with single dose rATG at 1.5 mg/kg/dose (±0.3 mg/kg/dose) for 3 days provided effective and safe outcomes in pediatric kidney transplant patients in this study.

1387. Impact of Cytomegalovirus Prophylaxis on Healthcare Resource Use and Costs among Kidney Transplant Recipients: A United States Renal Data System-Medicare Linked Database Study

BackgroundCytomegalovirus (CMV) management requires a balance between reducing the risk of CMV infection and avoiding anti-viral toxicities. Limited information is available on the impact of CMV prophylaxis on the healthcare resource use (HCRU) and costs among adult kidney transplant recipients (KTRs) in the United States. Therefore, we examined HCRU and cost associated with CMV prophylaxis stratified by the CMV risk categories among KTRs at 1-year post-KT. MethodsWe identified a cohort of 22,918 adults first-time KTRs during 2011–2017 using the US Renal Data System registry-linked Medicare data. Additional inclusion criteria were to have continuous coverage in Medicare Part A & B for ≥ 6-month pre- and ≥ 12-month post KT and Medicare Part D for ≥12-month post-KT. CMV prophylaxis was confirmed as ≥ 1 prescription fill for valacyclovir/(val)ganciclovir prophylaxis doses within 28 days post-KT. ResultsCMV prophylaxis was utilized in 86%, 82%, and 32% of high, intermediate, and low-risk KTRs with an average cost of prophylaxis per KTRs of &16,241, &9481, and &8,648, respectively. In no prophylaxis groups, valganciclovir was utilized in 52%, 34%, and 36% of KTRs (as either pre-emptive or deferred therapy) with an average cost of &6,719, &2,722, and &431 among high, intermediate, and low-risk KTRs, respectively. Among high-risk KTRs, CMV prophylaxis group had a significantly higher prescription drug cost (&26,060 vs. &13,433) but a lower average direct healthcare medical cost (&84,914 vs. &101,268), mainly due to lower all-cause hospitalization cost (&56,758 vs. &69,852) (Table 1). CMV prophylaxis group had lower rates of all-cause rehospitalization, and CMV-and opportunistic infection (OIs)-related hospitalization compared to no prophylaxis (Table 2). In high-risk KTRs, nearly 32% had myelosuppressive events-related hospitalization, and 15% filled granulocyte colony-stimulating factors with an average cost of &4,695 per treated KTR.ConclusionCMV prophylaxis had a higher cost of medications but had a lower medical cost with including all-cause and CMV-related hospitalizations. Myelosuppressive events were frequent and resource-intensive especially in high and intermediate-risk KTRs. Disclosures Amit D. Raval, PhD, Merck and Co., Inc. (Employee) Yuexin Tang, PhD, JnJ (Other Financial or Material Support, Spouse’s employment)Merck & Co., Inc. (Employee, Shareholder)

Belatacept in Kidney Transplant Recipients With Failed Allografts for the Prevention of Humoral Sensitization: A Pilot Randomized Controlled Trial.

Belatacept in Kidney Transplant Recipients With Failed Allografts for the Prevention of Humoral Sensitization: A Pilot Randomized Controlled Trial.

Outcomes of Kidney Transplant Recipients with Sickle Cell Disease: An Analysis of the 2000-2019 UNOS/OPTN Database.

Background: Lower patient survival has been observed in sickle cell disease (SCD) patients who go on to receive a kidney transplant. This study aimed to assess the post-transplant outcomes of SCD kidney transplant recipients in the contemporary era. Methods: We used the OPTN/UNOS database to identify first-time kidney transplant recipients from 2010 through 2019. We compared patient and allograft survival between recipients with SCD (n = 105) vs. all other diagnoses (non-SCD, n = 146,325) as the reported cause of end-stage kidney disease. We examined whether post-transplant outcomes improved among SCD in the recent era (2010–2019), compared to the early era (2000–2009). Results: After adjusting for differences in baseline characteristics, SCD was significantly associated with lower patient survival (HR 2.87; 95% CI 1.75–4.68) and death-censored graft survival (HR 1.98; 95% CI 1.30–3.01), compared to non-SCD recipients. The lower patient survival and death-censored graft survival in SCD recipients were consistently observed in comparison to outcomes of recipients with diabetes, glomerular disease, and hypertension as the cause of end-stage kidney disease. There was no significant difference in death censored graft survival (HR 0.99; 95% CI 0.51–1.73, p = 0.98) and patient survival (HR 0.93; 95% CI 0.50–1.74, p = 0.82) of SCD recipients in the recent versus early era. Conclusions: Patient and allograft survival in SCD kidney recipients were worse than recipients with other diagnoses. Overall SCD patient and allograft outcomes in the recent era did not improve from the early era. The findings of our study should not discourage kidney transplantation for ESKD patients with SCD due to a known survival benefit of transplantation compared with remaining on dialysis. Urgent future studies are needed to identify strategies to improve patient and allograft survival in SCD kidney recipients. In addition, it may be reasonable to assign risk adjustment for SCD patients.

The Risk of Postkidney Transplant Outcomes by Induction Choice Differs by Recipient Age.

Among adult kidney transplant (KT) recipients, the risk of post-KT adverse outcomes differs by type of induction immunosuppression. Immune response to induction differs as recipients age; yet, choice of induction is barely tailored by age likely due to a lack of evidence of the risks and benefits. Using Scientific Registry of Transplant Recipients data, we identified 39336 first-time KT recipients (2010-2016). We estimated the length of stay (LOS), acute rejection (AR), graft failure, and death by induction type using logistic and Cox regression weighted by propensity score to adjust for confounders. We tested whether these estimates differed by age (65+ versus 18-64 y) using a Wald test. Overall, rabbit antithymocyte globulin (rATG) was associated with a decreased risk of AR (odds ratio = 0.79, 95% confidence interval [CI], 0.72-0.85) compared with basiliximab. The effect of induction on LOS and death (interaction P = 0.03 and 0.003) differed by recipient age. Discharge was on average 11% shorter in rATG among younger recipients (relative time = 0.89; 95% confidence interval [CI], 0.81-0.99) but not among older recipients (relative time = 1.01; 95% CI, 0.95-1.08). rATG was not associated with mortality among older (hazard ratio = 1.05; 95% CI, 0.96-1.15), but among younger recipients (hazard ratio = 0.87; 95% CI, 0.80-0.95), it was associated with reduced mortality risk. rATG should be considered to prevent AR, especially among recipients with high-immunologic risk regardless of age; however, choice of induction should be tailored to reduce LOS and risk of mortality, particularly among younger recipients.

Low-Dose Antithymocyte Globulin Has No Disadvantages to Standard Higher Dose in Pediatric Kidney Transplant Recipients: Report From the Pediatric Nephrology Research Consortium

IntroductionRabbit antithymocyte globulin (rATG) dosing strategies for induction in pediatric kidney transplantation vary between centers. It is not known whether a lower rATG induction dose provides safe and effective immunosuppression compared with a “standard” higher dose.MethodsWe performed a retrospective multicenter study of all isolated first-time kidney transplant recipients <21 years old who received rATG induction between 1 January 2010 and 31 December 2014 at 9 pediatric centers. An a priori cutoff of a 4.5-mg/kg cumulative rATG dose was used to identify low (≤ 4.5 mg/kg) and standard (> 4.5 mg/kg) exposure groups. Outcomes examined included 12 months posttransplant graft function (estimated glomerular filtration rate [eGFR]); the occurrence of acute rejection, donor-specific antibody (DSA), neutropenia, and viral infection (cytomegalovirus [CMV], Epstein-Barr virus [EBV], and BK virus); and 24-month outcomes of posttransplant lymphoproliferative disorder (PTLD) occurrence and patient and graft survival.ResultsTwo hundred thirty-five patients were included. Baseline features of the low and standard rATG dose groups were similar. By 12 months, the rATG dose group had no significant impact on the occurrence of neutropenia, positive DSA, or viral polymerase chain reaction (PCR). Graft function was similar. Acute rejection rates were similar at 17% (low dose) versus 19% (standard dose) (P = 0.13). By 24 months, graft survival (96.4% vs. 94.6%) and patient survival (100% vs. 99.3%) were similar between the low- and standard-dose groups (P = 0.54 and 0.46), whereas the occurrence of PTLD trended higher in the standard-dose group (0% vs. 2.6%, P = 0.07).ConclusionA low rATG induction dose ≤ 4.5 mg/kg provided safe and effective outcomes in this multicenter low immunologic risk pediatric cohort. Prospective studies are warranted to define the optimal rATG induction dose in pediatric kidney transplantation.

Reassessing Rabbit Antithymocyte Globulin Induction in Kidney Transplantation (RETHINK): An Analysis of the North American Pediatric Renal Trials and Collaborative Studies (NAPRTCS) Registry.

There is no consensus on rabbit antithymocyte globulin (rATG) dose used for induction immunosuppression in pediatric kidney transplants. We aimed to identify whether a lower rATG dose provides safe and effective immunosuppression compared with a higher dose. We retrospectively analyzed all first-time kidney transplant recipients (aged <21 y) in the North American Pediatric Renal Trials and Collaborative Studies registry since 1998 on mycophenolate mofetil- and tacrolimus-based immunosuppression with rATG induction. An a priori cutoff of 7.5 mg/kg cumulative rATG dose was used to identify low (<7.5 mg/kg) and high (≥7.5 mg/kg) exposure groups. Primary outcome was time to first-acute rejection episode. Secondary outcomes included graft function, patient survival, hospitalizations due to infections, and time to first-posttransplant lymphoproliferative disorder episode. Four hundred fifty-five patients met inclusion criteria (59% male, 49% whites, 26% blacks, 38% living donor source). Median cumulative rATG dose was 6.8 mg/kg with a median of 5 doses and a median 1.5 mg/kg/dose introduced at a median of postoperative 0 days. Sixty-four percent received <7.5 mg/kg total rATG. There was no difference in age at transplant, gender, race, end-stage renal disease causes, or HLA mismatch among groups. Time to first-acute rejection was similar (P = 0.07). There was no significant difference in graft or patient survival or time to posttransplant lymphoproliferative disorder. Hospitalization for infection rates was similar. These data demonstrate a wide variation in cumulative rATG induction dose. A smaller rATG dose <7.5 mg/kg may provide effective and safe immunosuppression compared with a higher dose.

P1631EFFECT OF DONOR TYPE ON 3-MONTH HOSPITAL READMISSION AFTER KIDNEY TRANSPLANTATION

Abstract Background and Aims Hospital readmission after kidney transplantation remains a burden not only for the kidney transplant recipients (KTRs) but also for the healthcare system. Therefore, it can also indicate the quality of care. The causes of hospital readmission in KTRs mainly include problematic graft function and complications caused by the invasive procedure or immunosuppressive regime. In the Netherlands, almost 1000 kidney transplantations are performed annually with an aging recipient population. In spite of the benefit of living donor transplantation, roughly half of the patients will receive a graft from a donor donating after cardiac death(DCD) or brain death(DBD). From 2000 to 2017 the DCD procedure accounted for 43% of all deceased donors in the Netherlands, which is the highest worldwide. With this analysis, we aim to investigate the effect of donor type on 3-month hospital readmission after kidney transplantation and also investigate this effect in different age groups. Method Our study was conducted with data abstracted from the Netherlands Organ Transplant Registry (NOTR). We retrieved data for all first-time KTRs over 18 years old from 1st Jan 2016 to 31st Dec 2018. A multivariate logistic regression model with multiple imputation for missing values was used to estimate the hazard ratio (HR) of post-transplant 3-month hospital readmission for different donor types and control for confounding. KTRs with living or deceased donors and KTRs with DCD or DBD donors were compared, respectively. Subgroup group analysis was conducted to investigate the effect of different donor types on 3-month hospital readmission within different recipient age groups( age below 65 vs 65 years or older). Results Among 1917 first-time KTRs surviving 3 months with a functioning graft, 941 (49,1%) had no hospital readmission, 371 (19,4%) had one readmission in this period, and 244 (12,7%) had two or more readmissions (361 (18,8%) with missingness in readmission). Within the cohort, 1163(60,7%) received a graft from a living donor, 281(14,7%) from DBD donors and 473(24,7%) from DCD donors. 259(23,3,%) recipients with living donor kidney transplantation were 65 years old or older while it is 104 (43,3%) for recipients with DBD donors and 172(41,5%) for recipients with DCD donors. KTRs with living donors were at lower risk of 3-month hospital readmission after transplantation compared to those with deceased donors (HR, 0,77; 95%CI, 0,61 to 0,95). The difference was consistent in KTRs under 65 years old (HR, 0,70; 95%CI, 0,53 to 0,92) but disappeared in KTRs above 65 years old(HR, 0,90; 95%CI: 0,60 to 1,35) in subgroup analysis. KTRs with DCD and DBD donors had a similar risk of 3-month hospital readmission. Conclusion Kidney transplant recipients younger than 65 years of age with a living donor have a lower risk of post-transplant 3-month hospital readmission compared to those with a deceased donor. KTRs at an age of 65 or above KTRs with either a DCD or DBD donor are similar with regard to 3-month hospital readmission across different age groups.

Association Between Pre-Transplant Magnesemia and Post-Transplant Dysglycemia in Kidney Transplant Recipients.

BackgroundSerum magnesium (Mg) status in kidney transplant recipients has been a center of attention in the past few years. Current evidence suggests an association between pre-transplant hypomagnesemia and post-transplant hyperglycemia.ObjectiveThe purpose of this study was to assess the associations of pre-transplant magnesemia with blood glucose disturbances within 6 months post-kidney transplantation.MethodsIn this retrospective cohort, 89 first-time kidney transplant recipients with 6 months of follow-up were included. None of the participants had a positive history of rejection, pre-transplant history of diabetes mellitus or fasting plasma glucose ≥ 100 mg/dL.ResultsPost-transplant diabetes mellitus (PTDM) and impaired fasting glucose (IFG) 6 months post-transplant was found in 7.9% and 41.6% of the study group, respectively. The mean pre-transplant serum Mg level was 1.92 ± 0.30 mg/dL in the study population (n = 89), and it was significantly lower in IFG (n = 37) and IFG/PTDM (n = 44) groups compared to normoglycemic (n = 45) recipients (1.83 ± 0.31 mg/dL vs. 2.00 ± 0.27 mg/dL, P = 0.008, and 1.84 ± 0.31 mg/dL vs. 2.00 ± 0.27 mg/dL, P = 0.012, respectively). Patients with serum Mg less than 1.9 mg/dL were nearly 2.6 times more likely to develop IFG or IFG/PTDM within 6 months post-transplant (P = 0.044 and P = 0.040, respectively).ConclusionsPre-transplant hypomagnesemia may be considered a risk factor for developing post-transplant glycemic disturbances, and patients with lower pre-transplant Mg concentration could be at a higher risk for developing IFG.

Vitamin D as a risk factor for patient survival after kidney transplantation: A prospective observational cohort study.

Short-term survival after kidney transplantation is excellent, but long-term survival remains low and is equivalent to non-end-stage renal disease patients with many invasive malignancies. The aim of the study was to explore vitamin D status in the early phase after transplantation as a prognostic marker for long-term graft and patient survival. All first-time kidney transplant recipients between October 2007 and October 2012 in Norway were included. Vitamin D was measured 10weeks post-transplant. Information on graft failure and death was obtained from the Norwegian Renal Registry. Seven hundred and sixty-two first-time kidney transplant recipients were included, with a median age of 57years and a median follow-up of 82months. In the follow-up period, there were 172 graft failures (23%) and 118 deaths (15%). Eighty-six percent of the transplant recipients with sufficient vitamin D levels were alive with a well-functioning graft after 5years using Kaplan-Meier survival estimates, compared with 79% and 76% of the patients with vitamin D deficiency and insufficiency, respectively (P=0.006). In a nation-wide cohort of 762 first-time kidney transplant recipients, long-term graft and patient survival were better in recipients with vitamin D sufficiency 10weeks post-transplant compared with those with vitamin D deficiency and insufficiency.

Early Hospital Readmission in Older and Younger Kidney Transplant Recipients

Background: Up to 31% of kidney transplant (KT) recipients experience early hospital readmission (EHR). We hypothesized that EHR among older KT recipients is higher than younger recipients due to increased comorbidities and higher prevalence of frailty. Methods: We identified 22,458 older (age ≥65) and 86,372 younger (18 to < 65) first-time KT recipients (December 1, 1999 – December 31, 2014) using United States Renal Data System data. We estimated the association between patient-level characteristics and EHR (30 days post-KT discharge) with modified Poisson regression among older and younger KT recipients, separately. We estimated the association between graft loss and mortality and EHR using Cox proportional hazards. Results: EHR was more common in older KT recipients (30.1 vs. 27.6%; p < 0.001). Risk factors for EHR that differed by recipient age included female sex, African American race, diabetes, smoking, dialysis vintage, donor age, and length of stay. Risk of graft loss associated with EHR was greater among older KT recipients (adjusted hazard ratio [aHR] 1.64, 95% CI 1.51–1.77, p < 0.001) than younger KT recipients (aHR 1.43, 95% CI 1.38–1.48, p < 0.001; interaction p < 0.01). However, the risk of mortality associated with EHR was greater among younger recipients (aHR 1.52, 95% CI 1.47–1.57, p < 0.001) than that in older ­recipients (aHR 1.40, 95% CI 1.34–1.47, p < 0.001; interaction p < 0.01). Conclusions: Older KT recipients are more likely to experience EHR and are at a higher risk of graft loss after EHR than younger recipients. Targeted interventions to prevent EHR and subsequent graft loss in this population should be identified.

Statin use and hip fractures in U.S. kidney transplant recipients

BackgroundBasic and translational research supports beneficial effects of statins on bone metabolism. Clinical studies suggest that statin use may reduce the risk of hip fractures in the general population. Whether statin use is associated with hip fracture risk in kidney transplant recipients, a particularly high-risk group for this outcome, is unknown.MethodsFrom the U.S. Renal Data System (2007–2011), we identified all hip fracture events recorded in Medicare billing claims of first-time kidney transplant recipients. We then matched all cases to an unlimited number of controls on age (±3 years), sex, race (black vs. non-black), and time since transplant. Cases and controls were required to have >1 year of Medicare Parts A + B + D coverage and be without a recorded history of hip fracture. We ascertained any statin use in the previous year and defined adherent statin use as those who had filled prescriptions for statins to cover >80% of days in that year (proportion of days covered, PDC). We ascertained several potential confounders (demographics, comorbidities, BMI, transplant-related factors) and applied conditional logistic regression with multiple imputation for missing data to estimate odds ratios (OR) and 95% confidence intervals (CI).ResultsWe identified 231 hip fracture cases (mean age 51.8 years; 53% female; 11.3% black; 6.9 years from transplant, and 9.9 years from ESRD) and 15,575 matched controls. Any prior statin use was present in 64.1% of cases and 60.3% of controls with 37.2% of cases and 33.9% of controls being found adherent. Unadjusted conditional logistic regression showed an OR of 1.17 (0.89-1.54) for any statin use, and a fully-adjusted OR of 0.89 (0.67-1.19). Compared with statin non-users, the adjusted OR for patients with lesser adherence (PDC ≤80%) and those with greater adherence (PDC >80%) were 0.93 (0.66-1.31) and 0.87 (0.63-1.20), respectively.ConclusionStatin use was not associated with hip fracture risk in first-time kidney transplant recipients.