Patient survival and cardiovascular risk after kidney transplantation: the challenge of diabetes

Pulmonary Artery Systolic Pressure Measured Intraoperatively by Right Heart Catheterization Is a Predictor of Kidney Transplant Recipient Survival

BACKGROUND The effect of pulmonary artery systolic pressure (PASP) measured by Swan-Ganz right heart catheter (SG-RHC) on kidney transplant recipient survival has not been previously studied. The objective of this study was to assess the relationships between PASP measured via SG-RHC, done intraoperatively at the time of initiating anesthesia at the beginning of kidney transplant surgery, and patient survival. Multiple comorbidities, time on dialysis before the transplantation, and graft function were also analyzed in our study. MATERIAL AND METHODS This was a retrospective cohort study using data from all consecutive patients undergoing kidney transplant between January 1, 2005 and December 31, 2009 at Tampa General Hospital. Kidney transplant recipients were divided into 2 groups: Group 1 with PASP <35 mmHg and group 2 with PASP ≥35 mmHg. Patients and graft survival data, time on dialysis before transplant, and comorbidities were compared between the 2 groups. RESULTS Only 363 patients were found to have a documented PASP measurement at the time of anesthesia induction for the transplant surgery, and were included in the specific analysis of our study. Patients with PASP ≥35 mmHg showed a significant decrease in survival in comparison to patients having PASP values <35 mmHg (HR 1.88; 95% CI 1.012 to 3.47, P=0.04). There was a significant positive correlation between time on dialysis and PASP (rho 0.20; 95% CI 0.09 to 0.30, p<0.001), as well as a significant difference in median time on dialysis between PASP <35 vs. PASP ≥35 (22 vs. 29 months, p=0.004). There were no significant differences in graft failure between the 2 PASP groups (HR 0.34; 95% CI 0.12 to 1.01, P=0.05). CONCLUSIONS Patients with PASP ≥35 mmHg, measured intraoperatively by SG-RHC, showed significantly shorter survival in comparison to patients having PASP values <35 mmHg. This result suggests the need for a randomized controlled trial to address the importance of post-transplant pulmonary hypertension management in patient survival.

Trends in the Causes of Death among Kidney Transplant Recipients in the United States (1996-2014)

BACKGROUND

Death with graft function remains an important cause of graft loss among kidney transplant recipients (KTRs). Little is known about the trend of specific causes of death in KTRs in recent years.

METHODS

We analyzed United States Renal Data System data (1996-2014) to determine 1- and 10-year all-cause and cause-specific mortality in adult KTRs who died with a functioning allograft. We also studied 1- and 10-year trends in the various causes of mortality.

RESULTS

Of 210,327 KTRs who received their first kidney transplant from 1996 to 2014, 3.2% died within 1 year after transplant. Cardiovascular deaths constituted the majority (24.7%), followed by infectious (15.2%) and malignant (2.9%) causes; 40.1% of deaths had no reported cause. Using 1996 as the referent year, all-cause as well as cardiovascular mortality declined, whereas mortality due to malignancy did not. For analyses of 10-year mortality, we studied 94,384 patients who received a first kidney transplant from 1996 to 2005. Of those, 22.1% died over 10 years and the causative patterns of their causes of death were similar to those associated with 1-year mortality.

CONCLUSIONS

Despite the downtrend in mortality over the last 2 decades, a significant percentage of KTRs die in 10-years with a functioning graft, and cardiovascular mortality remains the leading cause of death. These data also highlight the need for diligent collection of mortality data in KTRs.

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.

Clinical Consequences of Diabetes Mellitus in Patients After Kidney Transplantation: A Paired Kidney Analysis

BACKGROUND

Diabetes mellitus (DM) has been acknowledged as the most common disorder leading to end-stage renal failure in adults. Diabetic patients show higher survival rates after kidney transplantation (KTx) compared with dialysis therapy. The aim of the study was to evaluate follow-up after KTx in patients with DM as a reason of end-stage renal disease (ESRD), or with long-lasting diabetes before transplantation, compared with patients without DM.

METHODS

We retrospectively analyzed the clinical consequences of DM in patients after KTx performed at the Gdansk Transplantation Centre between 2000 and 2016. To minimize donor bias, a paired kidney analysis was applied.

RESULTS

The incidence of DM (types 1 and 2) was 13%; 145 patients with DM had pairs of nondiabetic patients, who received kidneys from the same donor and were included to the analysis. The DM group was older. The incidence of AR was similar among the 2 groups, DGF was observed more often in patients with diabetes. Kidney graft function 1 month after transplantation was equal in both groups (mean serum creatinine concentration 1.4 mg/dL). Five-year patient survival was better in the non-DM group (96.7% vs 81.5%). Kaplan-Meier survival curves did not differ significantly between the DM and non-DM groups. DM was not associated graft loss. In the univariate analysis age was the only factor associated with death.

CONCLUSION

Diabetic patient survival after KTx seems to be worse than in patients without diabetes, but generally the follow-up among diabetics is good, with graft survival similar to that observed in patients without DM.

The influence of clinical, environmental, and socioeconomic factors on five-year patient survival after kidney transplantation

INTRODUCTION

The risk of death after kidney transplant is associated with the age of the recipient, presence of comorbidities, socioeconomic status, local environmental characteristics and access to health care.

OBJECTIVE

To investigate the causes and risk factors associated with death during the first 5 years after kidney transplantation.

METHODS

This was a single-center, retrospective, matched case-control study.

RESULTS

Using a consecutive cohort of 1,873 kidney transplant recipients from January 1st 2007 to December 31st 2009, there were 162 deaths (case group), corresponding to 5-year patient survival of 91.4%. Of these deaths, 25% occurred during the first 3 months after transplant. The most prevalent cause of death was infectious (53%) followed by cardiovascular (24%). Risk factors associated with death were history of diabetes, dialysis type and time, unemployment, delayed graft function, number of visits to center, number of hospitalizations, and duration of hospital stay. After multivariate analysis, only time on dialysis, number of visits to center, and days in hospital were still associated with death. Patients who died had a non-significant higher number of treated acute rejection episodes (38% vs. 29%, p = 0.078), higher mean number of adverse events per patient (5.1 ± 3.8 vs. 3.8 ± 2.9, p = 0.194), and lower mean eGFR at 3 months (50.8 ± 25.1 vs. 56.7 ± 20.7, p = 0.137) and 48 months (45.9 ± 23.8 vs. 58.5 ± 20.2, p = 0.368).

CONCLUSION

This analysis confirmed that in this population, infection is the leading cause of mortality over the first 5 years after kidney transplantation. Several demographic and socioeconomic risk factors were associated with death, most of which are not readily modifiable.

Effect of post-transplant glycemic control on long-term clinical outcomes in kidney transplant recipients with diabetic nephropathy: A multicenter cohort study in Korea

PURPOSE

Diabetic nephropathy is the leading cause of end stage renal disease. The number of kidney transplantation (KT) due to diabetic nephropathy is increasing and there is debate on glycemic control after KT. In this study, we used a multi-center database to determine the relationship between post-transplant glycemic control and the outcomes of KT in patients with diabetic nephropathy.

METHODS

We conducted a retrospective chart review of kidney transplant recipients (KTRs) with diabetic nephropathy from three tertiary hospitals to analyze the association between post-transplant glycemic control and the clinical outcomes of graft failure, including patient death and biopsy-proven acute rejection (BPAR). We assessed time-averaged glucose level and hemoglobin A1c (HbA1c) for 36 months after KT.

RESULTS

Among 3,538 KTRs, a total of 476 patients received kidney transplantation because of diabetic nephropathy. Mean time-averaged glucose and HbA1c levels were 147 ± 46 mg/dl and 7.7 ± 1.5%, respectively. Patients with diabetic nephropathy had poor graft and patient survival rate compared with non-diabetic nephropathy. Among KTRs with diabetic nephropathy, the highest quartile of time-averaged glucose was related to poor graft outcomes and the 3rd quartile of time-averaged HbA1c was associated with significantly better graft outcomes than the 1st, 2nd or 4th quartiles. There were no significant differences in the risk of BPAR across the 4 quartiles of glucose and HbA1c.

CONCLUSIONS

Strict glycemic control before KT might not be related to successful outcomes but poor glycemic control after KT is associated with poor graft outcomes. There was no significant relationship between pre- or post-transplant glycemic control and BPAR.

Improving Medication Safety and Cardiovascular Risk Factor Control to Mitigate Disparities in African-American Kidney Transplant Recipients: Design and Methods

There is a lack of data analyzing the influence of cardiovascular disease (CVD) risk factor control on graft survival disparities in African-American kidney transplant recipients. Studies in the general population indicate that CVD risk factor control is poor in African-Americans, leading to higher rates of renal failure and major acute cardiovascular events. However, with the exception of hypertension, there is no data demonstrating similar results within transplant recipients. Recent analyses conducted by our investigator group indicate that CVD risk factors, especially diabetes, are poorly controlled in African-American recipients, which likely impacts graft loss. This study protocol describes a prospective interventional clinical trial with the goal of demonstrating improved medication safety and CVD risk factor control in adult solitary kidney transplant recipients at least one-year post-transplant with a functioning graft. This is a prospective, interventional, 6-month, pharmacist-led and technology enabled study in adult kidney transplant recipients with the goal of improving CVD risk factor outcomes by improving medication safety and patient self-efficacy. This papers describes the issues related to racial disparities in transplant, the details of this intervention and how we expect this intervention to improve CVD risk factor control in kidney transplant recipients, particularly within African-Americans.

Outcomes of living donor kidney transplantation in diabetic patients: age and sex matched comparison with non-diabetic patients

BACKGROUND/AIMS

Kidney transplantation (KT) reportedly provides a significant survival advantage over dialysis in diabetic patients. However, KT outcome in diabetic patients compared with that in non-diabetic patients remains controversial. In addition, owing to recent improvements in the outcomes of KT and management of cardiovascular diseases, it is necessary to analyze outcomes of recently performed KT in diabetic patients.

METHODS

We reviewed all diabetic patients who received living donor KT between January 2008 and December 2011. Each patient was age- and sex-matched with two non-diabetic patients who received living donor KT during the same period. The outcomes of living donor KT were compared between diabetic and non-diabetic patients.

RESULTS

Among 887 patients, 89 diabetic patients were compared with 178 non-diabetic patients. The incidence of acute rejection was not different between the diabetic and non-diabetic patients. Urinary tract infection and other infections as well as cardiovascular events occurred more frequently in diabetic patients. However, diabetes, cardiovascular disease, and infection were not significant risk factors of graft failure. Late rejection (acute rejection after 1 year of transplantation) was the most important risk factor for graft failure after adjusting for diabetes mellitus (DM), human leukocyte antigen mismatch, rejection and infection (hazard ratio, 56.082; 95% confidence interval, 7.169 to 438.702; p < 0.001). Mortality was not significantly different between diabetic and non-diabetic patients (0 vs. 2, p = 0.344 by log-rank test).

CONCLUSIONS

End-stage renal disease patients with DM had favorable outcomes with living donor kidney transplantation.

Mortality in Elderly Waiting-List Patients Versus Age-Matched Kidney Transplant Recipients: Where is the Risk?

The number of elderly patients on the waiting list (WL) for kidney transplantation (KT) has risen significantly in recent years. Because KT offers a better survival than dialysis therapy, even in the elderly, candidates for KT should be selected carefully, particularly in older waitlisted patients. Identification of risk factors for death in WL patients and prediction of both perioperative risk and long-term post-transplant mortality are crucial for the proper allocation of organs and the clinical management of these patients in order to decrease mortality, both while on the WL and after KT. In this review, we examine the clinical results in studies concerning: a) risk factors for mortality in WL patients and KT recipients; 2) the benefits and risks of performing KT in the elderly, comparing survival between patients on the WL and KT recipients; and 3) clinical tools that should be used to assess the perioperative risk of mortality and predict long-term post-transplant survival. The acknowledgment of these concerns could contribute to better management of high-risk patients and prophylactic interventions to prolong survival in this particular population, provided a higher mortality is assumed.

Outcome of Patients With Small Vessel Vasculitis After Renal Transplantation: National Database Analysis

Background

Small vessel vasculitis commonly affects the kidney and can progress to end-stage renal disease. The goal of this study is to compare outcomes of patients who received a renal transplant as a result of small vessel vasculitis (group A) with those who received kidney transplants because of other causes (group B).

Methods

This is a retrospective analysis of United Network for Organ Sharing registry data for adult primary kidney transplants from January 2000 to December 2014. Group A patients (N = 2196) were compared with a group B (N = 6588); groups were case matched for age, race, sex, donor type, and year of transplant in a 1:3 ratio.

Results

Renal and patient survivals were better in the group A (P < 0.001). New-onset diabetes after transplant developed in 8.3% of the group A and 11.3% of group B (P < 0.001). Seventeen (0.8%) patients in group A developed recurrent disease. Of these, 7 patients had graft failure, 3 of which were due to disease recurrence. Group A patients had significantly higher risk of developing posttransplant solid organ malignancies (11.3% vs 9.3%, P = 0.006) and lymphoproliferative disorder (1.3% vs 0.8%, P = 0.026). Independent predictors of graft failure and patient mortality were recipients' morbid obesity, diabetes, age, and dialysis duration (hazard ratio of 1.7, 1.4, 1.1/10 years, and 1.1/year for graft failure, and 1.7, 1.7, 1.6/10 years and 1.1/year for patient mortality, respectively).

Conclusions

Renal transplantation in patients with has favorable long-term graft and patient outcomes with a low disease recurrence rate. However, they may have a higher risk of developing posttransplant malignancies.

Improved Glucose Tolerance in a Kidney Transplant Recipient With Type 2 Diabetes Mellitus After Switching From Tacrolimus To Belatacept: A Case Report and Review of Potential Mechanisms

Supplemental digital content is available in the text.

The introduction of immunosuppressant belatacept, an inhibitor of the CD28-80/86 pathway, has improved 1-year outcomes in kidney transplant recipients with preexistent diabetes mellitus and has also reduced the risk of posttransplant diabetes mellitus. So far, no studies have compared a tacrolimus-based with a belatacept-based immunosuppressive regimen with regard to improving glucose tolerance after kidney transplantation. Here, we present the case of a 54-year-old man with type 2 diabetes mellitus who was converted from belatacept to tacrolimus 1 year after a successful kidney transplantation. Thereafter, he quickly developed severe hyperglycemia, and administration of insulin was needed to improve metabolic control. Six months after this episode, he was converted back to belatacept because of nausea, diarrhea, and hyperglycemia. After switching back to belatacept and within 4 days after stopping tacrolimus glucose tolerance improved and insulin therapy could be discontinued. Although belatacept is considered less diabetogenic than tacrolimus, the rapid improvement of glucose tolerance after switching to belatacept is remarkable. In this article, the potential mechanisms of this observation are discussed.

Early failure of kidney transplants in the current era-a national cohort study

Although short-term outcome after kidney transplantation has improved, a small proportion of grafts are lost during the first year. We characterize in detail all early graft losses in the current era in a nationwide cohort of kidney transplant recipients. Altogether 2447 kidney transplantations, performed between June 2004 and October 2016, were included. All graft losses (return to dialysis or patient death) occurring during the first post-transplant year were characterized. During the first post-tranplant year, altogether 109 grafts were lost, 67 grafts failed, and 42 patients died. Fifty-five per cent of the deaths were due to cardiovascular causes, and 29% due to infectious causes. Twenty-one per cent of the failed grafts were primary nonfunction of unknown reason, 34% were lost due to venous thrombosis and 9% due to arterial thrombosis, but only 10 (15%) patients lost a graft due to acute cellular or humoral rejection. Independent risk factors for death included diabetes, and longer duration of pretransplant dialysis treatment, whereas risk factors for graft failure included increased level of panel-reactive antibodies and increased cold ischaemia time. Kidney allografts are rarely lost due to immunological reasons during the first post-transplant year. The most common causes of early death after transplantation are cardiovascular and infectious causes.

Predictive Score for Posttransplantation Outcomes

BACKGROUND

Most current scoring tools to predict allograft and patient survival upon kidney transplantion are based on variables collected posttransplantation. We developed a novel score to predict posttransplant outcomes using pretransplant information including routine laboratory data available before or at the time of transplantation.

METHODS

Linking the 5-year patient data of a large dialysis organization to the Scientific Registry of Transplant Recipients, we identified 15 125 hemodialysis patients who underwent first deceased transplantion. Prediction models were developed using Cox models for (a) mortality, (b) allograft loss (death censored), and (c) combined death or transplant failure. The cohort was randomly divided into a two thirds set (Nd = 10 083) for model development and a one third set (Nv = 5042) for validation. Model predictive discrimination was assessed using the index of concordance, or C statistic, which accounts for censoring in time-to-event models (a-c). We used the bootstrap method to assess model overfitting and calibration using the development dataset.

RESULTS

Patients were 50 ± 13 years of age and included 39% women, 15% African Americans, and 36% persons with diabetes. For prediction of posttransplant mortality and graft loss, 10 predictors were used (recipients' age, cause and length of end-stage renal disease, hemoglobin, albumin, selected comorbidities, race and type of insurance as well as donor age, diabetes status, extended criterion donor kidney, and number of HLA mismatches). The new model (www.TransplantScore.com) showed the overall best discrimination (C-statistics, 0.70; 95% confidence interval [95% CI], 0.67-0.73 for mortality; 0.63; 95% CI, 0.60-0.66 for graft failure; 0.63; 95% CI, 0.61-0.66 for combined outcome).

CONCLUSIONS

The new prediction tool, using data available before the time of transplantation, predicts relevant clinical outcomes and may perform better to predict patients' graft survival than currently used tools.

Surgical Techniques and Procedures for Kidney Transplant Recipients With Severe Atherosclerosis

OBJECTIVES

Atherosclerosis is becoming a more common problem for dialysis patients. Therefore, transplant surgeons are faced with the need to develop surgical techniques and procedures for severe atherosclerosis. This study aimed to clarify the clinical features, the usefulness of examinations, and operative procedures for kidney transplant recipients with the complication of severe atherosclerosis.

MATERIALS AND METHODS

Among 220 kidney transplant candidates, 13 patients (severe atherosclerosis group) were predicted complications due to arterial calcification in the bilateral iliac arterial system using a computed tomographic scan. They were compared with the remaining 207 patients (mild atherosclerosis group) based on patient characteristics. The severe atherosclerosis group was evaluated by additional examination, anastomosis procedure of the graft artery, and patient outcome.

RESULTS

The severe atherosclerosis group had significantly higher rates of mean recipient age, glycosylated hemoglobin A1c, past smoking, and administration of antithrombotics. Past vascular surgery related to atherosclerosis in the aortoiliac region had been performed in 8 patients from the severe atherosclerosis group. A three-dimensional computed tomography angiography and an intraoperative periarterial echography were useful to determine the kidney transplant site. A balloon catheter effectively blocked blood flow. A polytetrafluoroethylene vascular graft was used for bypass between the graft artery and abdominal aorta. All kidney grafts of the severe atherosclerosis group were functioning well.

CONCLUSIONS

Kidney transplant for patients with severe atherosclerosis can be achieved successfully by additional examinations and vascular surgical techniques.

Risk Factors of Recurrence of Diabetic Nephropathy in Renal Transplants

BACKGROUND

Renal transplantation has been established as the treatment of choice for end-stage renal disease (ESRD) due to diabetic nephropathy. This study aimed to investigate the risk factors for recurrence of diabetic nephropathy (RDN) in renal allografts.

METHODS

We studied 1,011 renal transplant patients from 1986 to 2003, of which 95 had ESRD due to diabetic nephropathy. We retrospectively analyzed the clinical characteristics and outcomes of RDN after renal transplantation.

RESULTS

Of the 95 recipients with ESRD due to diabetic nephropathy, 41 developed RDN and 11 of those 41 underwent graft biopsy. The mean durations from transplantation to RDN and to renal replacement therapy was 81.58 months (range, 54-120 mo), and 109.66 months (range, 27-188.4 mo), respectively. At 5 years, treatment on statins and renin-angiotensin-aldosterone system (RAAS) blockers were associated with a higher survival free from RND (82.2% vs 63.2% [P = .070] and 100% vs 80% vs 0.6% [P = .013], respectively). Compared with cyclosporine, tacrolimus was associated with a higher risk for RND (odds ratio [OR], 4.27; 95% confidence interval [CI], 1.75-5.13; P = .047). High doses of prednisone (>0.06 mg/kg) were also associated with a higher risk of RDN (OR, 3.03; 95% CI, 1.19-8.30; P = .029). The combination of calcineurin inhibitor and mammalian target of rapamycin inhibitor (mTORi) demonstrated the highest risk of RDN (OR, 14.08; 95% CI, 3.72-53.29; P < .01).

CONCLUSIONS

Treatment with tacrolimus and mTORi is the most diabetogenic immunosuppressive regimen. Treatment with tacrolimus entails a greater risk of RDN than with cyclosporine. The administration of statins or RAAS blockers could delay the progression of RDN.

High-risk cutaneous malignancies and immunosuppression: Challenges for the reconstructive surgeon in the renal transplant population

Renal transplantation is the most frequently performed transplant procedure. Immunosuppressive therapies have dramatically increased survival rates in transplant recipients but are associated with an increased risk of skin cancers. Recent changes in immunosuppressive strategies have been adopted with the aim of reducing this challenging adverse effect. Despite these new strategies, cutaneous malignancies tend to be numerous, aggressive and associated with a higher risk of local and distant dissemination than in the non-transplant population. This represents a significant workload for transplant physicians, dermatologists, and head and neck and plastic surgeons. This review highlights key concepts in the pathogenesis of skin cancer in transplant patients, the impact current and evolving immunosuppressive strategies and regimens will have on the epidemiology, and the management of cutaneous malignancies in renal transplant patients, with particular focus on the implications for the plastic surgery community.

Glucose-lowering agents for treating pre-existing and new-onset diabetes in kidney transplant recipients

BACKGROUND

Kidney transplantation is the preferred form of kidney replacement therapy for patients with end-stage kidney disease (ESKD) and is often complicated by worsening or new-onset diabetes. Management of hyperglycaemia is important to reduce post-transplant and diabetes-related complications. The safety and efficacy of glucose-lowering agents after kidney transplantation is largely unknown.

OBJECTIVES

To evaluate the efficacy and safety of pharmacological interventions for lowering glucose levels in patients who have undergone kidney transplantation and have diabetes.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Specialised Register to 15 April 2016 through contact with the Information Specialist using search terms relevant to this review. Studies contained in the Specialised Register are identified through search strategies specifically designed for CENTRAL, MEDLINE, and EMBASE; handsearching conference proceedings; and searching the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

All randomised controlled trials (RCTs), quasi-RCTs and cross-over studies examining head-to-head comparisons of active regimens of glucose-lowering therapy or active regimen compared with placebo/standard care in patients who have received a kidney transplant and have diabetes were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study eligibility and quality and performed data extraction. Continuous outcomes were expressed as post-treatment mean differences (MD) or standardised mean difference (SMD). Adverse events were expressed as post-treatment absolute risk differences (RD). Dichotomous clinical outcomes were presented as risk ratios (RR) with 95% confidence intervals (CI).

MAIN RESULTS

We included seven studies that involved a total of 399 kidney transplant recipients. All included studies had observed heterogeneity in the patient population, interventions and measured outcomes or missing data (which was unavailable despite correspondence with authors). Many studies had incompletely reported methodology preventing meta-analysis and leading to low confidence in treatment estimates.Three studies with 241 kidney transplant recipients examined the use of more intensive compared to less intensive insulin therapy in kidney transplant recipients with pre-existing type 1 or 2 diabetes. Evidence for the effects of more intensive compared to less intensive insulin therapy on transplant graft survival, HbA1c, fasting blood glucose, all cause mortality and adverse effects including hypoglycaemia was of very low quality. More intensive versus less intensive insulin therapy resulted in no difference in transplant or graft survival over three to five years in one study while another study showed that more intensive versus less intensive insulin therapy resulted in more rejection events over the three year follow-up (11 events in total; 9 in the more intensive group, P = 0.01). One study showed that more intensive insulin therapy resulted in a lower mean HbA1c (10 ± 0.8% versus 13 ± 0.9%) and lower fasting blood glucose (7.22 ± 0.5 mmol/L versus 13.44 ± 1.22 mmol/L) at 13 months compared with standard insulin therapy. Another study showed no difference between more intensive compared to less intensive insulin therapy on all-cause mortality over a five year follow-up period. All studies showed either an increased frequency of hypoglycaemia or severe hypoglycaemia episodes.Three studies with a total of 115 transplant recipients examined the use of DPP4 inhibitors for new-onset diabetes after transplantation. Evidence for the treatment effect of DPP4 inhibitors on transplant or graft survival, HbA1c and fasting blood glucose levels, all cause mortality, and adverse events including hypoglycaemia was of low quality. One study comparing vildagliptin to placebo and another comparing sitagliptin to placebo showed no difference in transplant or graft survival over two to four months of follow-up. One study comparing vildagliptin to placebo showed no significant change in estimated glomerular filtration rate from baseline (1.9 ± 10.3 mL/min/1.73 m2, P = 0.48 and 2.1 ± 6.1 mL/min/1.73 m2, P = 0.22) and no deaths, in either treatment group over three months of follow-up. One study comparing vildagliptin to placebo showed a lower HbA1c level (mean ± SD) (6.3 ± 0.5% versus versus 6.7 ± 0.6%, P = 0.03) and trend towards a greater lowering of fasting blood glucose (-0.91 ± -0.92 mmol/L versus vs -0.19 ± 1.16 mmol/L, P = 0.08) with vildagliptin. One study comparing sitagliptin to insulin glargine showed an equivalent lowering of HbA1c (-0.6 ± 0.5% versus -0.6 ± 0.6%, P = NS) and fasting blood glucose (4.92 ± 1.42 versus 4.76 ± 1.09 mmol/L, P = NS) with sitagliptin. For the outcome of hypoglycaemia, one study comparing vildagliptin to placebo reported no episodes of hypoglycaemia, one study comparing sitagliptin to insulin glargine reported fewer episodes of hypoglycaemia with sitagliptin (3/28 patients; 10.7% versus 5/28; 17.9%) and one cross-over study of sitagliptin and placebo reported two episodes of asymptomatic moderate hypoglycaemia (2 to 3.9 mmol/L) when sitagliptin was administered with glipizide. All three studies reported no drug interactions between DPP4 inhibitors and the immunosuppressive agents taken.Evidence for the treatment effect of pioglitazone for treating pre-existing diabetes was of low quality. One study with 62 transplant recipients compared the use of pioglitazone with insulin to insulin alone for treating pre-existing diabetes. Pioglitazone resulted in a lower HbA1c level (mean ± SD) (-1.21 ± 1.2 versus 0.39 ± 1%, P < 0.001) but had no effects on fasting blood glucose (6.58 ± 2.71 versus 7.28 ± 2.78 mmol/L, P = 0.14 ), and change in creatinine (3.54 ± 15.03 versus 10.61 ± 18.56 mmol/L, P = 0.53) and minimal adverse effects (no episodes of hypoglycaemia, three dropped out due to mild to moderate lower extremity oedema, cyclosporin levels were not affected).

AUTHORS' CONCLUSIONS

Evidence concerning the efficacy and safety of glucose-lowering agents for treating pre-existing and new-onset diabetes in kidney transplant recipients is limited. Existing studies examine more intensive versus less intensive insulin therapy, and the use of DPP4 inhibitors and pioglitazone. The safety and efficacy of more intensive compared to less intensive insulin therapy is very uncertain and the safety and efficacy of DPP4 inhibitors and pioglitazone is uncertain, due to data being limited and of poor quality. Additional RCTs are required to clarify the safety and efficacy of current glucose-lowering agents for kidney transplant recipients with diabetes.

The effect of aspirin on kidney allograft outcomes; a short review to current studies

CONTEXT

The use of aspirin in chronic kidney disease (CKD) patients has been shown to reduce myocardial infarction but may increase major bleeding. However, its effects in kidney transplant recipients are unclear.

EVIDENCE ACQUISITIONS

A literature search was performed using MEDLINE, EMBASE, and Cochrane Database of Systematic Reviews from inception through September 2016. We included studies that reported odd ratios, relative risks or hazard ratios comparing outcomes of aspirin use in kidney transplant recipients. Pooled risk ratios (RR) and 95% confidence interval (CI) were assessed using a random-effect, generic inverse variance method.

RESULTS

We included 9 studies; enrolling 19759 kidney transplant recipients that compared aspirin with no treatment. Compared to no treatment, aspirin reduced the risk of allograft failure (4 studies; RR: 0.57, 95% CI: 0.33 to 0.99), allograft thrombosis (2 studies; RR: 0.11, 95% CI: 0.02 to 0.53), and major adverse cardiac events (MACEs) or mortality (2 studies; RR: 0.72, 95% CI: 0.59 to 0.88), but not allograft rejection (3 studies; RR: 0.86, 95% CI: 0.45 to 1.65) or delayed graft function (DGF) (2 studies; RR: 1.00, 95% CI: 0.58 to 1.72) in kidney transplant recipients. The data on risk of major or minor bleeding were limited.

CONCLUSIONS

Our meta-analysis demonstrates that administration of aspirin in kidney transplant recipients is associated with reduced risks of allograft failure, allograft thrombosis, and MACEs or mortality, but not allograft rejection or DGF. Future studies are needed to assess the risk of bleeding, and ultimately weigh the overall risks and benefits of aspirin use in specific kidney transplant patient populations.

Renal transplant among type 1 and type 2 diabetes patients in Spain: A population-based study from 2002 to 2013

BACKGROUND

To describe trends in the rates and short-term outcomes of renal transplants (RTx) among patients with or without diabetes in Spain (2002-2013).

METHODS

We used national hospital discharge data to select all hospital admissions for RTx. We divided the study period into four three-year periods. Rates were calculated stratified by diabetes status: type 1 diabetes (T1DM), type 2 diabetes (T2DM) and no-diabetes. We analyzed Charlson comorbidity index (CCI), post-transplant infections, in-hospital complications of RTx, rejection, in-hospital mortality and length of hospital stay.

FINDINGS

We identified 25,542 RTx. Rates of RTx increased significantly in T2DM patients over time (from 9.3 cases/100,000 in 2002/2004 to 13.3 cases/100,000 in 2011/2013), with higher rates among people with T2DM for all time periods. T2DM patients were older and had higher CCI values than T1DM and non-diabetic patients (CCI≥1, 31.4%, 20.4% and 21.5%, respectively; P<0.05). Time trend analyses showed significant increases in infections, RTx-associated complications and rejection for all groups (all P values<0.05). Infection rates were greater in people with T2DM (20.8%) and T1DM (23.5%) than in non-diabetic people (18.7%; P<0.05). Time trend analyses (2002-2013) showed significant decreases in mortality during admission for RTx (OR 0.75, 95% CI 0.68-0.83). Diabetes was not associated with a higher in-hospital mortality (OR: 1.20, 95% CI 0.92-1.55).

INTERPRETATION

RTx rates were higher and increased over time at a higher rate among T2DM patients. Mortality decreased over time in all groups. Diabetes does not predict mortality during admission for RTx.

FUNDING

Instituto Salud Carlos III and URJC-Banco Santander.

Long-term outcomes of kidney transplantation in people with type 2 diabetes: a population cohort study

BACKGROUND

Overall survival for younger patients with type 2 diabetes without kidney disease has improved substantially over time, but whether a similar pattern of improvement is observed in diabetic kidney transplant recipients remained uncertain. We aimed to compare patient outcomes between diabetic and non-diabetic transplant recipients, and to determine the effect of age and era on patient survival.

METHODS

This population cohort study included all primary kidney-only transplant recipients included in the Australia and New Zealand Dialysis and Transplant registry between Jan 1, 1994, and Dec 31, 2012. The primary outcomes were all-cause mortality and death with functioning graft. Associations between outcomes and diabetes status were examined using adjusted Cox regression, and interactions between diabetes status and transplant era and recipient age were examined.

FINDINGS

Of 10 714 transplant recipients, 985 (9%) had type 2 diabetes. Mortality rates in the first 10 years after transplantation were higher in recipients with diabetes (25·3 per 100 recipients) compared to those without diabetes (11·5 per 100 recipients). Compared with recipients without diabetes, the adjusted hazard ratios (HR) for all-cause mortality and death with a functioning graft in recipients with diabetes were 1·60 (95% CI 1·37-1·86; p<0·0001) and 1·54 (1·28-1·85 p<0·0001), respectively. The association between diabetes status, all-cause mortality, and death with a functioning graft was modified by recipient age (p_interaction<0·0001), with the highest risk in recipients with diabetes aged younger than 40 years (adjusted HR 5·16 [95% CI 2·84-9·35], p<0·0001; and 9·83 [4·51-21·43], p<0·0001; for all-cause mortality and death with a functioning graft, respectively). Risk was increased to a lesser extent in recipients with diabetes aged older than 55 years (adjusted HR 1·41 [95% CI 1·17-1·71; p=0·002] and 1·27 [1·02-1·59; p=0·03], for all-cause mortality and death with a functioning graft, respectively). Transplant era did not modify the association between diabetes status and mortality.

INTERPRETATION

Kidney transplant recipients with type 2 diabetes had substantially poorer patient survival, with 5-year mortality rates exceeding those for non-diabetic recipients by over two times. The magnitude of this survival disadvantage was greatest in recipients with diabetes aged less than 40 years. By contrast with the general population, there was no evidence of improvement in mortality over time among people with type 2 diabetes following kidney transplantation.

FUNDING

None.

Effects of acute rejection vs new-onset diabetes after transplant on transplant outcomes in pediatric kidney recipients: analysis of the Organ Procurement and Transplant Network/United Network for Organ Sharing (OPTN/UNOS) database

Improving long-term transplant and patient survival is still an ongoing challenge in kidney transplant medicine. Our objective was to identify the subsequent risks of new-onset diabetes after transplant (NODAT) and acute rejection (AR) in the first year post-transplant in predicting mortality and transplant failure. A total of 4687 patients without preexisting diabetes (age 2-20 years, 2004-2010) surviving with a functioning transplant for longer than 1 year with at least one follow-up report were identified from the OPTN/UNOS database as of September 2014. Study population was stratified into four mutually exclusive groups: Group 1, patients with a history of AR; Group 2, NODAT+; Group 3, NODAT+ AR+; and Group 4, the reference group (neither). Multivariate regression was used to analyze the relative risks for the outcomes of transplant failure and mortality. The median follow-up time was 1827 days after 1 year post-transplant. AR was associated with an increased risk of adjusted graft and death-censored graft failure (HR 2.87, CI 2.48-3.33, P < .001 and HR 2.11, CI 1.81-2.47, P < .001), respectively. NODAT and AR were identified in 3.5% and 14.5% of all study patients, respectively. AR in the first year post-transplant was a major risk factor for overall and death-censored graft failure, but not mortality. However, NODAT was not a risk factor on graft survival or mortality.

Use of the 'Accountability for Reasonableness' Approach to Improve Fairness in Accessing Dialysis in a Middle-Income Country

Universal access to renal replacement therapy is beyond the economic capability of most low and middle-income countries due to large patient numbers and the high recurrent cost of treating end stage kidney disease. In countries where limited access is available, no systems exist that allow for optimal use of the scarce dialysis facilities. We previously reported that using national guidelines to select patients for renal replacement therapy resulted in biased allocation. We reengineered selection guidelines using the ‘Accountability for Reasonableness’ (procedural fairness) framework in collaboration with relevant stakeholders, applying these in a novel way to categorize and prioritize patients in a unique hierarchical fashion. The guidelines were primarily premised on patients being transplantable. We examined whether the revised guidelines enhanced fairness of dialysis resource allocation. This is a descriptive study of 1101 end stage kidney failure patients presenting to a tertiary renal unit in a middle-income country, evaluated for dialysis treatment over a seven-year period. The Assessment Committee used the accountability for reasonableness-based guidelines to allocate patients to one of three assessment groups. Category 1 patients were guaranteed renal replacement therapy, Category 3 patients were palliated, and Category 2 were offered treatment if resources allowed. Only 25.2% of all end stage kidney disease patients assessed were accepted for renal replacement treatment. The majority of patients (48%) were allocated to Category 2. Of 134 Category 1 patients, 98% were accepted for treatment while 438 (99.5%) Category 3 patients were excluded. Compared with those palliated, patients accepted for dialysis treatment were almost 10 years younger, employed, married with children and not diabetic. Compared with our previous selection process our current method of priority setting based on procedural fairness arguably resulted in more equitable allocation of treatment but, more importantly, it is a model that is morally, legally and ethically more defensible.

Twenty years of evolving trends in racial disparities for adult kidney transplant recipients

Disparities in outcomes for African American (AA) kidney transplant recipients have persisted for 40 years without a comprehensive analysis of evolving trends in the risks associated with this disparity. Here we analyzed U.S. transplant registry data, which included adult Caucasian or AA solitary kidney recipients undergoing transplantation between 1990 and 2009 comprising 202,085 transplantations. During this 20-year period, the estimated rate of 5-year graft loss decreased from 27.6% to 12.8%. Notable trends in baseline characteristics that significantly differed by race over time included the following: increased prevalence of diabetes from 2001 to 2009 in AAs (5-year slope difference: 3.4%), longer time on the waiting list (76.5 more days per 5 years in AAs), fewer living donors in AAs from 2003 to 2009 (5-year slope difference: -3.36%), more circulatory death donors in AAs from 2000-09 (5-year slope difference: 1.78%), and a slower decline in delayed graft function in AAs (5-year slope difference: 0.85%). The absolute risk difference between AAs and Caucasians for 5-year graft loss significantly declined over time (-0.92% decrease per 5 years), whereas the relative risk difference actually significantly increased (3.4% increase per 5 years). These results provide a mixed picture of both promising and concerning trends in disparities for AA kidney transplant recipients. Thus, although the disparity for graft loss has significantly improved, equity is still far off, and other disparities, including living donation rates and delayed graft function rates, have widened during this time.

Pre-Transplant Cardiovascular Risk Factors Affect Kidney Allograft Survival: A Multi-Center Study in Korea

Background

Pre-transplant cardiovascular (CV) risk factors affect the development of CV events even after successful kidney transplantation (KT). However, the impact of pre-transplant CV risk factors on allograft failure (GF) has not been reported.

Methods and Findings

We analyzed the graft outcomes of 2,902 KT recipients who were enrolled in a multi-center cohort from 1997 to 2012. We calculated the pre-transplant CV risk scores based on the Framingham risk model using age, gender, total cholesterol level, smoking status, and history of hypertension. Vascular disease (a composite of ischemic heart disease, peripheral vascular disease, and cerebrovascular disease) was noted in 6.5% of the patients. During the median follow-up of 6.4 years, 286 (9.9%) patients had developed GF. In the multivariable-adjusted Cox proportional hazard model, pre-transplant vascular disease was associated with an increased risk of GF (HR 2.51; 95% CI 1.66–3.80). The HR for GF (comparing the highest with the lowest tertile regarding the pre-transplant CV risk scores) was 1.65 (95% CI 1.22–2.23). In the competing risk model, both pre-transplant vascular disease and CV risk score were independent risk factors for GF. Moreover, the addition of the CV risk score, the pre-transplant vascular disease, or both had a better predictability for GF compared to the traditional GF risk factors.

Conclusions

In conclusion, both vascular disease and pre-transplant CV risk score were independently associated with GF in this multi-center study. Pre-transplant CV risk assessments could be useful in predicting GF in KT recipients.

Superior outcomes of kidney transplantation compared with dialysis: An optimal matched analysis of a national population-based cohort study between 2005 and 2008 in Korea

Data regarding kidney transplantation (KT) and dialysis outcomes are rare in Asian populations. In the present study, we evaluated the clinical outcomes associated with KT using claims data from the Korean national public health insurance program. Among the 35,418 adult patients with incident dialysis treated between 2005 and 2008 in Korea, 1539 underwent KT. An optimal balanced risk set matching was attempted to compare the transplant group with the control group in terms of the overall survival and major adverse cardiac event-free survival. Before matching, the dialysis group was older and had more comorbidities. After matching, there were no differences in age, sex, dialysis modalities, or comorbidities. Patient survival was significantly better in the transplant group than in the matched control group (P < 0.001). In addition, the transplant group showed better major adverse cardiac event-free survival than the dialysis group (P < 0.001; hazard ratio, 0.49; 95% confidence interval, 0.32-0.75). Korean patients with incident dialysis who underwent long-term dialysis had significantly more cardiovascular events and higher all-cause mortality rates than those who underwent KT. Thus, KT should be more actively recommended in Korean populations.

Impact of Cardiovascular Risk Factors on Graft Outcome Disparities in Black Kidney Transplant Recipients

Although outcome inequalities for non-Hispanic black (NHB) kidney transplant recipients are well documented, there is paucity in data assessing the impact of cardiovascular disease (CVD) risk factors on this disparity in kidney transplantation. This was a longitudinal study of a national cohort of veteran kidney recipients transplanted between January 2001 and December 2007. Data included baseline characteristics acquired through the United States Renal Data System linked to detailed clinical follow-up information acquired through the Veterans Affairs electronic health records. Analyses were conducted using sequential multivariable modeling (Cox regression), incorporating blocks of variables into iterative nested models; 3139 patients were included (2095 non-Hispanic whites [66.7%] and 1044 NHBs [33.3%]). NHBs had a higher prevalence of hypertension (100% versus 99%; P<0.01) and post-transplant diabetes mellitus (59% versus 53%; P<0.01) with reduced control of hypertension (blood pressure <140/90 60% versus 69%; P<0.01), diabetes mellitus (A1c <7%, 35% versus 47%; P<0.01), and low-density lipoprotein (<100 mg/dL, 55% versus 61%; P<0.01). Adherence to medications used to manage CVD risk was significantly lower in NHBs. In the fully adjusted models, the independent risk of graft loss in NHBs was substantially reduced (unadjusted hazard ratio, 2.00 versus adjusted hazard ratio, 1.49). CVD risk factors and control reduced the influence of NHB race by 9% to 18%. Similar trends were noted for mortality, and estimates were robust across in sensitivity analyses. These results demonstrate that NHB kidney transplant recipients have significantly higher rates of CVD risk factors and reduced CVD risk control. These issues are likely partly related to medication nonadherence and meaningfully contribute to racial disparities for graft outcomes.

High mortality in diabetic recipients of high KDPI deceased donor kidneys

BACKGROUND

Deceased donor (DD) kidney quality is determined by calculating the Kidney Donor Profile Index (KDPI). Optimizing high KDPI (≥85%) DD transplant outcome is challenging. This retrospective study was performed to review our high KDPI DD transplant results to identify clinical practices that can improve future outcomes.

METHODS

We retrospectively calculated the KDPI for 895 DD kidney recipients transplanted between 1/2002 and 11/2013. Age, race, body mass index (BMI), retransplantation, gender, diabetes (DM), dialysis time, and preexisting coronary artery disease (CAD) (previous myocardial infarction (MI), coronary artery bypass (CABG), or stenting) were determined for all recipients.

RESULTS

About 29.7% (266/895) of transplants were from donors with a KDPI ≥85%. By Cox regression older age, diabetes, female gender, and dialysis time >4 years correlated with shorter patient survival time. Diabetics with CAD who received a high KDPI donor kidney had a significantly increased risk of death (HR 4.33 (CI 1.82-10.30), P=.001) compared to low KDPI kidney recipients. The Kaplan-Meier survival curve for diabetic recipients of high KDPI kidneys was significantly worse if they had preexisting CAD (P<.001 by log-rank test).

CONCLUSION

Patient survival using high KDPI donor kidneys may be improved by avoiding diabetic candidates with preexisting CAD.

Association of Dialysis Duration with Outcomes after Transplantation in a Japanese Cohort

BACKGROUND AND OBJECTIVES

Evidence regarding the differences in clinical outcomes after preemptive kidney transplantation (PKT) and non-PKT in Japan is lacking.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We conducted a retrospective cohort study at a single center in Japan. Consecutive patients ages >18 years old who had received a kidney transplant from a living donor between November of 2001 and December of 2013 at our institution (n=786) were enrolled. The primary study outcome was the occurrence of clinical events before the end of 2014. Clinical events were defined as any of the following: death with functioning graft (DWFG), graft loss, or post-transplant cardiovascular disease (CVD).

RESULTS

The median follow-up period was 61.0 (35.3-94.0) months. PKT was performed in 239 patients (30.4%). Clinical events occurred in 78 (9.9%). In the Cox proportional hazard model for univariate analysis, factors found to be associated with higher risk of clinical events included older age, men, ABO incompatibility, longer dialysis duration, diabetes, pretransplant CVD, and large ventricular mass index. PKT was associated with lower risk. Clinical event rate in patients who received a PKT was 3.3% compared with 10.8%, 11.1%, 10.4%, 10.2%, 16.7%, and 16.2% among patients who were on dialysis for <1, 1 to <2, 2 to <3, 3 to <4, 4 to <5, and ≥5 years before transplant, respectively (P=0.002). The multivariate analysis showed that ABO incompatibility (hazard ratio [HR], 2.98; 95% confidence interval [95% CI], 1.89 to 4.71), duration of dialysis per year (HR, 1.07; 95% CI, 1.03 to 1.11), and diabetes (HR, 3.54; 95% CI, 2.05 to 6.12) were only three independent risk factors for the incidence of clinical events.

CONCLUSIONS

Even in Japan, where the long-term outcomes of patients on hemodialysis are excellent, PKT could be beneficial to reduce DWFG, graft loss, and post-transplant CVD.

Post-Transplant Diabetes Mellitus: Causes, Treatment, and Impact on Outcomes

Post-transplant diabetes mellitus (PTDM) is a frequent consequence of solid organ transplantation. PTDM has been associated with greater mortality and increased infections in different transplant groups using different diagnostic criteria. An international consensus panel recommended a consistent set of guidelines in 2003 based on American Diabetes Association glucose criteria but did not exclude the immediate post-transplant hospitalization when many patients receive large doses of corticosteroids. Greater glucose monitoring during all hospitalizations has revealed significant glucose intolerance in the majority of recipients immediately after transplant. As a result, the international consensus panel reviewed its earlier guidelines and recommended delaying screening and diagnosis of PTDM until the recipient is on stable doses of immunosuppression after discharge from initial transplant hospitalization. The group cautioned that whereas hemoglobin A1C has been adopted as a diagnostic criterion by many, it is not reliable as the sole diabetes screening method during the first year after transplant. Risk factors for PTDM include many of the immunosuppressant medications themselves as well as those for type 2 diabetes. The provider managing diabetes and associated dyslipidemia and hypertension after transplant must be careful of the greater risk for drug-drug interactions and infections with immunosuppressant medications. Treatment goals and therapies must consider the greater risk for fluctuating and reduced kidney function, which can cause hypoglycemia. Research is actively focused on strategies to prevent PTDM, but until strategies are found, it is imperative that immunosuppression regimens are chosen based on their evidence to prolong graft survival, not to avoid PTDM.

Variation in Cost and Quality in Kidney Transplantation

BACKGROUND

Bending the cost curve in medical expenses is a high national priority. The relationship between cost and kidney allograft failure has not been fully investigated in the United States.

METHODS

Using Medicare claims from the United States Renal Data System, we determined costs for all adults with Medicare coverage who underwent kidney transplant January 1, 2007, to June 30, 2009. We compared relative cost (observed/expected payment) for year 1 after transplantation for all transplant centers, adjusting for recipient, donor, and transplant characteristics, region, and local wage index. Using program-specific reports from the Scientific Registry of Transplant Recipients, we correlated relative cost with observed/expected allograft failure between centers, excluding small centers.

RESULTS

Among 19,603 transplants at 166 centers, mean observed cost per patient per center was $65,366 (interquartile range, $55,094-$71,624). Mean relative cost was 0.99 (± 0.20); mean observed/expected allograft failure was 1.03 (± 0.46). Overall, there was no correlation between relative cost and observed/expected allograft failure (r = 0.096, P = 0.22). Comparing centers with higher than expected costs and allograft failure rates (lower performing) and centers with lower than expected costs and failure rates (higher-performing) showed differences in donor and recipient characteristics. As these characteristics were accounted for in the adjusted cost and allograft failure models, they are unlikely to explain the differences between higher- and lower-performing centers.

CONCLUSIONS

Further investigations are needed to determine specific cost-effective practices of higher- and lower-performing centers to reduce costs and incidence of allograft failure.

The Effect of Different Glycaemic States on Renal Transplant Outcomes

Background. Optimal glycaemic targets following transplantation are unknown. Understanding the impact of DM and posttransplant diabetes mellitus (PTDM) may improve patient and graft survival in transplant recipients. Aim. To determine the perioperative and one-year outcomes after renal transplantation and whether these outcomes are affected by preexisting DM, PTDM, or glycaemia during transplant admission. Method. Adult recipients of renal transplants from a single centre over 5.5 years were retrospectively reviewed. Measured outcomes during transplant admission included glycaemia and complications (infective complications, acute rejection, and return to dialysis) and, at 12 months, glycaemic control and complications (cardiovascular complication, graft failure). Results. Of 148 patients analysed, 29 (19.6%) had DM and 27 (18.2%) developed PTDM. Following transplantation, glucose levels were higher in patients with DM and PTDM. DM patients had a longer hospital stay, had more infections, and were more likely return to dialysis. PTDM patients had increased rates of acute rejection and return to dialysis. At 1 year after transplant, there were more cardiovascular complications in DM patients compared to those without DM. Conclusions. Compared to patients without DM, patients with DM or PTDM are more likely to suffer from complications perioperatively and at 12 months. Perioperative glycaemia is associated with graft function and may be a modifiable risk.

Outcomes in obese kidney transplant recipients

BACKGROUND

Kidney transplantation (KT) in obese patients is controversial. The present study aimed to evaluate patient and graft survival and post-transplantation complications between obese and nonobese recipients.

METHODS

Patients (n = 3,054) receiving a KT from 1998 to 2008 were divided according to body mass index (BMI) into 3 groups for analysis: group I: BMI <30 kg/m(2) (nonobese); group II: ≥30-34.9 kg/m(2) (class I obese); and group III: ≥35 kg/m(2) (class II and III obese).

RESULTS

Mean BMIs were: group I (n = 2,822): 22.6 ± 3.3 kg/m(2); group II (n = 185): 31.9 ± 1.3 kg/m(2); and group III (n = 47): 36.8 ± 1.7 kg/m(2). There were no differences among the 3 groups in patient demographic variables regarding race, sex, or organ source. One-year (I, 98%; II, 98%; III, 95%) and 5-year (I, 90%; II, 92%; III, 89%) patient survival rates were similar among groups. Graft survival rates at 1 year were 96% for groups I and II and 91.5% for group III. Five-year graft survivals were: I, 81%; II, 96%; and III, 79%. The most common cause of graft loss was death, and the main cause of death was infection in all groups. Obese patients were more likely to experience wound dehiscence (I, 1.9%; II, 7.6%; III, 19.1%; P < .001), develop new-onset diabetes after transplantation (NODAT; I, 16.2%; II, 27%; III, 36%; P < .001), and have a prolonged length of hospital stay (I, 11.3 ± 11.4 d; II, 14.5 ± 14.3 d; III, 15.9 ± 16.7 d; P < .001).

CONCLUSIONS

Obese recipients demonstrated outcomes similar to nonobese patients regarding patient and graft survival. However, they had higher rates of prolonged length of hospital stay, wound dehiscence, and NODAT.

mTOR inhibitor versus mycophenolic acid as the primary immunosuppression regime combined with calcineurin inhibitor for kidney transplant recipients: a meta-analysis

Background

A number of studies have provided information regarding the risks and benefits of mammalian target of rapamycin inhibitors (mTOR-I) combined with calcineurin inhibitors (CNI) versus mycophenolic acid (MPA).

Methods

Medline, Embase and the Cochrane Central Register of Controlled Trials were searched. Randomized controlled trials comparing mTOR-I to MPA as the primary immunosuppressive regimen in combination with CNI were selected and meta-analyzed.

Results

Eleven randomized controlled trials consisting of 4930 patients in total were included. No significant difference was observed in the risk of biopsy-proven acute rejection and patient death between the two groups. However, an increased risk of graft loss (relative risk (RR) = 1.20) and inferior graft function (creatinine clearance, weighted mean difference (WMD) = −2.41 μmol/L) were demonstrated in mTOR-I-treated patients. Patients treated with mTOR-I had a higher risk of new-onset diabetes mellitus (RR = 1.32), dyslipidemia, proteinuria (RR = 1.79), peripheral edema (RR = 1.34), thrombocytopenia (RR = 1.97) and lymphocoele (RR = 1.80), but a lower risk of cytomegalovirus infection (RR = 0.40), malignancy (RR = 0.64) and leucopenia (RR = 0.43). There was no difference in diarrhea, anemia, urinary tract infection, polyoma virus infection and impaired wound healing when mTOR-I was compared with MPA.

Conclusions

mTOR-I showed no particular superiority to MPA. Notably, mTOR-I had an increased risk of graft loss when combined with CNI, even when combined with a reduced dose of CNI. Therefore, the optimal dosage strategies for mTOR-I and CNI need to be further explored.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-015-0078-5) contains supplementary material, which is available to authorized users.

Cardiac response to early conversion from calcineurin inhibitor to everolimus in renal transplant recipients--a three-yr serial echocardiographic substudy of the randomized controlled CENTRAL trial

BACKGROUND

In transplant recipients, calcineurin inhibitors (CNIs) are associated with adverse cardiac effects while mTOR inhibitors have been reported to be beneficial. We performed a randomized controlled trial (RCT) in de novo renal transplant recipients examining cardiac responses of everolimus vs. CNI.

METHODS

This was a substudy of the three-yr CENTRAL study, an RCT on safety and efficacy of early (week 7 post-engraftment) conversion from cyclosporine A (CsA) to everolimus vs. continued CsA. Thirty-nine recipients [median age 64 yr, (range 31-81)] completed echocardiographic evaluations at baseline, one, and three yr.

RESULTS

After three yr, there was no difference between groups in left ventricle (LV) diastolic function, LV systolic function, LV morphology, and blood pressure response. We observed a relevant decrease in LV mass (CsA; 9.6%, p = 0.008, vs. everolimus; 7.0% reduction, p = 0.15), stabilized LV diastolic function, and a trend toward lower systolic blood pressure with 6 mmHg decrease in both arms (CsA, p = 0.08; everolimus, p = 0.14). Diastolic blood pressure was significantly reduced (8 mmHg decrease, p = 0.002) only in everolimus patients.

CONCLUSIONS

After three-yr follow-up, no clinically relevant effect on cardiac function of an early conversion from CsA to an everolimus-based immunosuppressive regimen was detected in de novo renal transplant recipients.

Kidney Transplantation in the Diabetic Patient

Diabetes mellitus is one of the most important causes of chronic kidney disease (CKD). In patients with advanced diabetic kidney disease, kidney transplantation (KT) with or without a pancreas transplant is the treatment of choice. We aimed to review current data regarding kidney and pancreas transplant options in patients with both type 1 and 2 diabetes and the outcomes of different treatment modalities. In general, pancreas transplantation is associated with long-term survival advantages despite an increased short-term morbidity and mortality risk. This applies to simultaneous pancreas kidney transplantation or pancreas after KT compared to KT alone (either living donor or deceased). Other factors as living donor availability, comorbidities, and expected waiting time have to be considered whens electing one transplant modality, rather than a clear benefit in survival of one strategy vs. others. In selected type 2 diabetic patients, data support cautious utilization of simultaneous pancreas kidney transplantation when a living kidney donor is not an option. Pancreas and kidney transplantation seems to be the treatment of choice for most type 1 diabetic and selected type 2 diabetic patients.

Outcome of renal transplantation in patients with type 2 diabetic nephropathy: a single-center experience

BACKGROUND

Renal transplantation has been established as a treatment for end-stage renal disease (ESRD) due to diabetic nephropathy. However, few studies have focused on the outcome after renal transplantation in patients with ESRD and type 2 diabetic nephropathy. To investigate the effect of renal transplantation on ESRD with type 2 diabetic nephropathy, we retrospectively analyzed patients who received renal transplantation at our facility. This study aimed to compare the outcome of renal transplantation for type 2 diabetic nephropathy with that for nondiabetic nephropathy.

METHODS

We studied 290 adult patients, including 65 with type 2 diabetic nephropathy (DM group) and 225 with nondiabetic nephropathy (NDM group), who underwent living-donor renal transplantation at our facility from February 2008 to March 2013. We compared the 2 groups retrospectively.

RESULTS

In the DM and NDM groups, the 5-year patient survival rates were 96.6% and 98.7%, and the 5-year graft survival rates were 96.8% and 98.0%, respectively, with no significant differences between the groups. There were no significant differences in the rates of surgical complications, rejection, and infection. The cumulative incidence of postoperative cardiovascular events was higher in the DM group than in the NDM group (8.5% vs 0.49% at 5 years; P = .002).

CONCLUSIONS

Patient and graft survival rates after renal transplantation for type 2 diabetic nephropathy are not inferior to those for recipients without diabetic nephropathy. Considering the poor prognosis of patients with diabetic nephropathy on dialysis, renal transplantation can provide significant benefits for these patients.

The Kidney Transplant Morbidity Index (KTMI): A Simple Prognostic Tool to Help Determine Outcome Risk in Kidney Transplant Candidates

Background

The Kidney Transplant Morbidity Index (KTMI) is a novel prognostic morbidity index to help determine the impact that pretransplant comorbid conditions have on transplant outcome.

Objective

To use national data to validate the KTMI.

Design

Retrospective analysis of the Organ Procurement and Transplant Network/United Network for Organ Sharing database.

Setting and Participants

The study sample consisted of 100 261 adult patients who received a kidney transplant between 2000 and 2008.

Main Outcome Measure

Kaplan-Meier survival curves were used to demonstrate 3-year graft and patient survival for each KTMI score. Cox proportional hazards regression models were created to determine hazards for 3-year graft failure and patient mortality for each KTMI score.

Results

A sequential decrease in graft survival (0 = 91.2%, 1 = 88.2%, 2 = 85.4%, 3 = 81.7%, 4 = 77.8%, 5 = 74.0%, 6 = 69.8%, and ≥7 = 68.7) and patient survival (0 = 98.2%, 1 = 96.6%, 2 = 93.7%, 3 = 89.7%, 4 = 84.8%, 5 = 80.8%, 6 = 76.0%, and ≥7 = 74.7%) is seen as KTMI scores increase. The differences in graft and patient survival between KTMI scores are all significant ( P < .001) except between 6 and ≥7. Multivariate regression analysis reveals that KTMI is an independent predictor of higher graft failure and patient mortality rates and that risk increases as KTMI scores increase.

Conclusion

The KTMI strongly predicts graft and patient survival by using pretransplant comorbid conditions; therefore, this easy-to-use tool can aid in determining outcome risk and transplant candidacy before listing, particularly in candidates with multiple comorbid conditions.

Single-centre study of 628 adult, primary kidney transplant recipients showing no unfavourable effect of new-onset diabetes after transplant

AIMS/HYPOTHESIS

To better understand the implications of new-onset diabetes after transplant (NODAT), we used our prospectively followed cohort of 628 adult primary kidney transplant recipients to determine the prognostic impact of pretransplant diabetes and NODAT.

METHODS

The study cohort consisted of all participants in four randomised immunosuppression trials performed at our centre since May 2000. For each cause-specific hazard analysed, Cox stepwise regression was used to determine a multivariable model of significant baseline predictors; the multivariable influence of having pretransplant diabetes and NODAT (t) (the latter defined as a zero-one, time-dependent covariate) was subsequently tested. Similar analyses of estimated glomerular filtration rate (eGFR) at 36 and 60 months post transplant were performed using stepwise linear regression. Finally, a repeated measures analysis of mean HbA1c as a function of diabetes category (pretransplant diabetes vs NODAT) and randomised trial (first to fourth) was performed.

RESULTS

Median follow-up was 56 months post transplant. Patients with pretransplant diabetes comprised 23.4% (147/628), and 22.5% (108/481) of the remaining patients developed NODAT. Pretransplant diabetes had no prognostic influence on first biopsy-proven acute rejection and death-censored graft failure hazard rates, nor on eGFR, but was associated with significantly higher rates of death with a functioning graft (DWFG) (p = 0.003), DWFG due to a cardiovascular event (p = 0.005) and infection that required hospitalisation (p = 0.03). NODAT (t) had no unfavourable impact on any of these hazard rates nor on eGFR, with actuarial freedom from DWFG remaining at over 90% among patients in pre- and post-NODAT states at 72 months post transplant/NODAT. Mean HbA1c for patients in the first to fourth randomised trials, averaged across diabetes category, decreased by trial (7.28%, 6.92%, 6.87% and 6.64% [56.1, 52.1, 51.6 and 49.1 mmol/mol], respectively; p = 0.02).

CONCLUSIONS/INTERPRETATION

Less-than-expected post-NODAT risk for graft loss and death may exist in the current climate of tighter glucose monitoring post transplant.

Implementation of guidelines for metabolic syndrome control in kidney transplant recipients: results at a single center

BACKGROUND

Cardiovascular disease is a leading cause of death among kidney transplant recipients. Metabolic syndrome increases the risk for cardiovascular events and decreases graft survival. Lately, guidelines for management of the metabolic syndrome, primarily hypertension, diabetes mellitus (DM) and hypercholesterolemia have dramatically changed in an attempt to decrease cardiovascular risks among kidney transplant recipients. In the present study we examined whether these guideline changes had impact on our management of post-transplantation patients and the subsequent treatment outcomes for these diseases.

METHODS

Data were obtained from kidney transplant clinic files from two follow-up (FU) periods-between 1994-1997 and between 2008-2011. Demographic data, monitoring and screening frequency for cardiovascular risk factors, immunosuppression regimen, treatment for hypertension, diabetes and hyperlipidemia, treatment outcomes and graft function changes were compared between the two follow-up periods.

RESULTS

There was a significant increase in the percentage of patients undergoing transplantation due to renal failure secondary to diabetes and/or hypertension. Patient monitoring and screening during the second FU period were less frequent, but more targeted, reflecting changes in clinic routines. Blood pressure was better controlled in the second FU period (p < 0.01), as was hypercholesterolemia (p < 0.001). High fasting glucose levels were more prevalent among patients in the second group (p < 0.005), although more patients received treatment for DM (p < 0.001). Significantly, fewer patients experienced deterioration of kidney functions during the second FU period (p < 0.001).

CONCLUSIONS

We found that guideline changes had impact on clinical practice, which translated to better control of the metabolic syndrome. DM control is challenging. Overall, stability of kidney function improved.

Negative impact of underlying non-insulin-dependent diabetes mellitus nephropathy on long-term allograft survival in kidney transplantation: a 10-year analysis from a single center

INTRODUCTION

We analyzed the relationship between underlying nephropathy and long-term outcomes in kidney transplant recipients.

METHODS

We retrospectively analyzed data from 678 patients who underwent kidney transplantation (KTx) between 1998 and 2011. Recipients with 13 major nephropathies were evaluated for graft and patient survival, and causes of graft loss.

RESULTS

The best 10-year graft survival rates (100%) were in the patients with autosomal-dominant polycystic kidney disease, preeclampsia, Alport syndrome, and purpura nephritis. The worst rate (50.8%) was in patients with non-insulin-dependent diabetes mellitus nephropathy (NIDDMN; P = .039). Causes of graft-loss in the NIDDM patients included chronic rejection (6 cases), acute rejection (3 cases), infection (2 cases), and cardiovascular event (2 cases). Significant risk factors for graft loss were donor age (P < .01) and NIDDMN (P < .01).

CONCLUSION

Underlying NIDDMN before KTx was a significant risk factor for long-term graft function. Immunologic factors and nonimmunologic factors influenced the long-term outcomes in patients with underlying NIDDMN.

Long-term impact of human leukocyte antigen mismatches combined with expanded criteria donor on allograft outcomes in deceased donor kidney transplantation

The long-term impact of human leukocyte antigen (HLA) mismatches combined with expanded criteria donors (ECD) on clinical outcomes has not been fully evaluated in recipients of deceased donor (DD) kidney transplantations. Of 595 DD renal transplant recipients in our center between 1991 and 2011, 210 recipients (36%) had 0-3 HLA mismatches/standard criteria donor (SCD), 353 (59%) had 4-6 HLA mismatches/SCD or 0-3 HLA mismatches/ECD, and 32 (5%) had 4-6 HLA mismatches/ECD. The mortality rate was significantly highest in the patients with 4-6 HLA mismatches/ECD (p = 0.040). The most common cause of death in this group was infection (50%). There were no significant differences in overall graft survival and death-censored graft survival. The biopsy-proven acute rejection rate was significantly higher in the 4-6 HLA mismatches/ECD group (p = 0.011). Cox-regression multivariate analyses showed that 4-6 HLA mismatches plus ECD (adjusted hazard ratio [AHR], 3.2; 95% confidence interval [CI], 1.17-10.56) and diabetes (AHR, 4.3; 95% CI, 1.50-12.28) were significant predictors of recipient mortality. In conclusion, ≥4 HLA mismatches plus ECD were associated with significantly higher rates of biopsy-proven acute rejection and mortality compared with other groups undergoing DD kidney transplantation.

Significant racial differences in the key factors associated with early graft loss in kidney transplant recipients

BACKGROUND

There is continued and significant debate regarding the salient etiologies associated with graft loss and racial disparities in kidney transplant recipients.

METHODS

This was a longitudinal cohort study of all adult kidney transplant recipients, comparing patients with early graft loss (<5 years) to those with graft longevity (surviving graft with at least 5 years of follow-up) across racial cohorts [African-American (AA) and non-AA] to discern risk factors.

RESULTS

524 patients were included, 55% AA, 151 with early graft loss (29%) and 373 with graft longevity (71%). Consistent within both races, early graft loss was significantly associated with disability income [adjusted odds ratio (AOR) 2.2, 95% CI 1.1-4.5], Kidney Donor Risk Index (AOR 3.2, 1.4-7.5), rehospitalization (AOR 2.1, 1.0-4.4) and acute rejection (AOR 4.4, 1.7-11.6). Unique risk factors in AAs included Medicare-only insurance (AOR 8.0, 2.3-28) and BK infection (AOR 5.6, 1.3-25). Unique protective factors in AAs included cardiovascular risk factor control: AAs with a mean systolic blood pressure <150 mm Hg had 80% lower risk of early graft loss (AOR 0.2, 0.1-0.7), while low-density lipoprotein <100 mg/dl (AOR 0.4, 0.2-0.8), triglycerides <150 mg/dl (AOR 0.4, 0.2-1.0) and hemoglobin A1C <7% (AOR 0.2, 0.1-0.6) were also protective against early graft loss in AA, but not in non-AA recipients.

CONCLUSIONS

AA recipients have a number of unique risk factors for early graft loss, suggesting that controlling cardiovascular comorbidities may be an important mechanism to reduce racial disparities in kidney transplantation.

Transplant options for patients with type 2 diabetes and chronic kidney disease

Chronic kidney disease (CKD) has become a real epidemic around the world, mainly due to ageing and diabetic nephropathy. Although diabetic nephropathy due to type 1 diabetes mellitus (T1DM) has been studied more extensively, the vast majority of the diabetic CKD patients suffer from type 2 diabetes mellitus (T2DM). Renal transplantation has been established as a first line treatment for diabetic nephropathy unless there are major contraindications and provides not only a better quality of life, but also a significant survival advantage over dialysis. However, T2DM patients are less likely to be referred for renal transplantation as they are usually older, obese and present significant comorbidities. As pre-emptive renal transplantation presents a clear survival advantage over dialysis, all T2DM patients with CKD should be referred for early evaluation by a transplant center. The transplant center should have enough time in order to examine their eligibility focusing on special issues related with diabetic nephropathy and explore the best options for each patient. Living donor kidney transplantation should always be considered as the first line treatment. Otherwise, the patient should be listed for deceased donor kidney transplantation. Recent progress in transplantation medicine has improved the “transplant menu” for T2DM patients with diabetic nephropathy and there is an ongoing discussion about the place of simultaneous pancreas kidney (SPK) transplantation in well selected patients. The initial hesitations about the different pathophysiology of T2DM have been forgotten due to the almost similar short- and long-term results with T1DM patients. However, there is still a long way and a lot of ethical and logistical issues before establishing SPK transplantation as an ordinary treatment for T2DM patients. In addition recent advances in bariatric surgery may offer new options for severely obese T2DM patients with CKD. Nevertheless, the existing data for T2DM patients with advanced CKD are rather scarce and bariatric surgery should not be considered as a cure for diabetic nephropathy, but only as a bridge for renal transplantation.