Diabetes Mellitus as Predictor of Patient and Graft Survival After Kidney Transplantation

Stratification of Kidney Transplant Recipients Into Five Subgroups Based on Temporal Disease Trajectories

Background

Kidney transplantation is the treatment of choice for patients with end-stage renal disease. Considerable clinical research has focused on improving graft survival and an increasing number of kidney recipients die with a functioning graft. There is a need to improve patient survival and to better understand the individualized risk of comorbidities and complications. Here, we developed a method to stratify recipients into similar subgroups based on previous comorbidities and subsequently identify complications and for a subpopulation, laboratory test values associated with survival.

Methods

First, we identified significant disease patterns based on all hospital diagnoses from the Danish National Patient Registry for 5752 kidney transplant recipients from 1977 to 2018. Using hierarchical clustering, these longitudinal patterns of diseases segregate into 3 main clusters of glomerulonephritis, hypertension, and diabetes. As some recipients are diagnosed with diseases from >1 cluster, recipients are further stratified into 5 more fine-grained trajectory subgroups for which survival, stratified complication patterns as well as laboratory test values are analyzed.

Results

The study replicated known associations indicating that diabetes and low levels of albumin are associated with worse survival when investigating all recipients. However, stratification of recipients by trajectory subgroup showed additional associations. For recipients with glomerulonephritis, higher levels of basophils are significantly associated with poor survival, and these patients are more often diagnosed with bacterial infections. Additional associations were also found.

Conclusions

This study demonstrates that disease trajectories can confirm known comorbidities and furthermore stratify kidney transplant recipients into clinical subgroups in which we can characterize stratified risk factors. We hope to motivate future studies to stratify recipients into more fine-grained, homogenous subgroups to better discover associations relevant for the individual patient and thereby enable more personalized disease-management and improve long-term outcomes and survival.

Outcome of Renal Transplantation in Patients With Diabetes Mellitus: A Single-Center Experience

BACKGROUND

An increasing proportion of kidney recipients have diabetes mellitus (DM). Some concerns have been raised about the kidney transplantation results in diabetic patients. Therefore, we assessed the effect of DM on morbidity and mortality of diabetic patients with renal transplantation.

METHODS

We retrospectively studied adult patients with and without DM who underwent living donor transplantation between 2007 and 2016. Information concerning demographic and clinical data were retrospectively analyzed by reviewing the patient files.

RESULTS

Of the 1536 transplant recipients, 126 (8%) had diabetes mellitus (mean age 49.4 ± 11.8) and 525 patients were evaluated in the non-diabetic control group (mean age 36.2 ± 15.9). The diabetic and non-diabetic patient groups had a mean follow-up after kidney transplantation 42.5 months (0.27-101.7 months) and 58.8 ± 10.6 months, respectively. In the diabetic patient group, only 3 patients had lost graft and 13 patients were exitus. Three patients had lost graft and 5 patients were exitus in non-diabetic patient group. Cardiac death (54.5%) was the most common cause of mortality in diabetic group. The 6-year patient and graft survival rates are 84.9% and 95.3%; 97.5% and 97.2% in the diabetic and non-diabetic patient groups, respectively.

CONCLUSIONS

Both infection and cardiovascular diseases increase morbidity and mortality in renal transplant patients with diabetes mellitus. The mortality risk of diabetic patients after renal transplantation is higher than the non-diabetic kidney recipients. Therefore, diabetic patients need meticulous cardiac evaluation before renal transplantation and a close follow-up, in terms of infection, after transplantation.

Trends in the effects of pre-transplant diabetes on mortality and cardiovascular events after kidney transplantation

AIMS/INTRODUCTION

It is not clear whether survival in kidney transplant recipients with pre-transplant diabetes has improved over the past decades. We compared the rates of mortality and major adverse cardiovascular events (MACE) after renal transplantation in patients with and without pre-transplant diabetes. Furthermore, we investigated whether transplant era and recipient age affected the association between diabetes status and adverse events.

MATERIALS AND METHODS

This retrospective cohort study included 691 patients who underwent renal transplantation between 1994 and 2016 at a single tertiary center. We compared the incidences of post-transplant mortality and four-point MACE in patients with and without pre-transplant diabetes using Kaplan-Meier analysis and the Cox proportional hazard model, and assessed the interactions between diabetes status and transplant era and recipient age.

RESULTS

Of 691 kidney recipients, 143 (20.7%) had pre-transplant diabetes. The mean follow-up duration was 94.5 months. Kaplan-Meier analysis showed that patients with pre-transplant diabetes had higher incidences of post-transplant mortality and four-point MACE compared with those without pre-transplant diabetes (log-rank test, P < 0.001 for both). After adjusting for potential confounding factors, pre-transplant diabetes was associated with an increased risk of post-transplant mortality and four-point MACE (hazard ratio 1.90, 95% confidence interval 1.05-3.44, P = 0.034; and hazard ratio 1.75; 95% confidence interval 1.02-3.00, P = 0.043, respectively). The associations between pre-transplant diabetes status and all-cause mortality and four-point MACE were not affected by transplant era or recipient age.

CONCLUSIONS

Pre-transplant diabetes remains a significant risk factor for mortality and four-point MACE in kidney transplant recipients.

Intraoperative glycemic control in patients undergoing Orthotopic liver transplant: a single center prospective randomized study

Background

Perioperative hyperglycemia is associated with poor outcomes yet evidence to guide intraoperative goals and treatment modalities during non-cardiac surgery are lacking. End-stage liver disease is associated with altered glucose homeostasis; patients undergoing liver transplantation display huge fluctuations in blood glucose (BG) and represent a population of great interest. Here, we conduct a randomized trial to compare the effects of strict versus conventional glycemic control during orthotopic liver transplant (OLT).

Methods

Following approval by the Institutional Review Board of the University of Michigan Medical School and informed consent, 100 adult patients undergoing OLT were recruited. Patients were randomized to either strict (target BG 80–120 mg/dL) or conventional (target BG 180–200 mg/dL) BG control with block randomization for diabetic and nondiabetic patients. The primary outcomes measured were 1-year patient and graft survival assessed on an intention to treat basis. Graft survival is defined as death or needing re-transplant (www.unos.org). Three and 5-year patient and graft survival, infectious and biliary complications were measured as secondary outcomes. Data were examined using univariate methods and Kaplan-Meir survival analysis. A sensitivity analysis was performed to compare patients with a mean BG of ≤120 mg/dL and those > 120 mg/dL regardless of treatment group.

Results

There was no statistically significant difference in patient survival between conventional and strict control respectively;1 year, 88% vs 88% (p-0.99), 3 years, 86% vs 84% (p- 0.77), 5 years, 82% vs 78. % (p-0.36). Graft survival was not different between conventional and strict control groups at 1 year, 88% vs 84% (p-0.56), 3 years 82% vs 76% (p-0.46), 5 years 78% vs 70% (p-0.362).

Conclusion

There was no difference in patient or graft survival between intraoperative strict and conventional glycemic control during OLT.

Trial registration

Clinical trial number and registry: www.clinicaltrials.gov NCT00780026. This trial was retrospectively registered on 10/22/2008.

Diabetes and the solid organ transplant recipient

Solid organ transplant candidates undergo very strict screening for cardiovascular risk. Such screening has permitted significant decreases in cardiovascular morbidity and mortality over the ensuing decades of follow up. Long term follow-up has enabled us to identify an increasing incidence of pulmonary and urinary tract infections with or without sepsis as competing factors of morbidity and mortality. Indeed, all-cause mortality may now be dominated by infection-related endpoints. No population of transplant recipients is more naturally susceptible to infection as a diabetic subset, now submitted to immunosuppression. The current review details infection risk for kidney, liver, heart, and lung allograft recipients. A specific feature of this report emphasizes the enhanced risk for bacterial and fungal infection found in diabetic allograft recipients on immunosuppression therapy. The risk of repeated prescription of antibiotics in terms of evolutions of resistant strains of infectious pathogens is emphasized.

In-hospital outcomes for solid organ transplants according to type 2 diabetes status: An observational, 15-year study in Spain

AIMS

To describe trends and outcomes during admission for solid organ transplant in people with or without type 2 diabetes in Spain, 2001-2015.

METHODS

We used national hospital discharge data to select all hospital admissions for kidney, lung, heart, and liver transplant. We estimated admission rates stratified by type 2 diabetes status. We built Poisson regression models to compare the adjusted time trends in admission rates. We tested in-hospital mortality (IHM) in logistic regression analyses.

RESULTS

We identified 50 964 transplants (16.7% in people with type 2 diabetes): kidney, 30 919; lung, 2810; heart, 3649; liver, 13 586. The overall adjusted incidence rate ratios (95% confidence intervals) of admission in people with type 2 diabetes vs no diabetes were 2.4 (2.32-2.48) for kidney, 1.51 (1.33-1.70) for lung, 2.87 (2.63-3.13) for heart, and 4.16 (3.99-4.33) for liver transplant. In the multivariate analysis, IHM decreased significantly over time for all types of transplant. Type 2 diabetes independently predicted lower IHM during admission only for heart (Odds ratio, OR [95% CI] = 0.62 [0.47-0.81]) and liver transplant (OR [95% CI] = 0.69 [0.58-0.82]).

CONCLUSIONS

Admission rates for solid organ transplant were higher in people with type 2 diabetes than in people without diabetes. Type 2 diabetes was associated with lower in-hospital mortality during admission for heart and liver transplant.

Smoking and outcomes in kidney transplant recipients: a post hoc survival analysis of the FAVORIT trial

Background

Tobacco use remains an international health problem with between 10% and 40% of adults currently using tobacco. Given the rising number of patients either awaiting or having received a kidney transplant and the absence of smoking cessation as the criterion for transplantation in guidelines, we explored the association between smoking status and clinical outcomes in kidney transplant recipients.

Patients and methods

In this post hoc analysis of the Folic Acid for Vascular Outcome Reduction in Transplant trial, the associations between smoking status, defined as never having smoked, formerly or currently smoking, and both all-cause mortality and graft survival were assessed using Cox proportional hazards models. Fatal events were centrally adjudicated into prespecified categories: all-cause, cardiovascular and non-cardiovascular causes. Graft loss was defined as return to dialysis or retransplantation. Clinical Trials URL: http://www.clinicaltrials.gov/show/NCT00064753.

Results

Among 4110 transplant recipients, there were 451 current smokers and 1611 former smokers. The mortality rate per 100 patient-years was 4.0 (71 deaths) for smokers, 3.5 (226 deaths) for former smokers and 2.4 (116 deaths) for never smokers. Hazard ratio for mortality for current smokers was 1.70 (CI=1.26–2.29, p=0.001) and for former smokers was 1.21 (0.98–1.50, p=0.08) with 1.0 representing never smokers. As the number of cardiovascular deaths was similar in each group (all p>0.3), the differences between groups was driven by non-cardiovascular death rates. Current smokers (2.39; 1.62–3.61, p<0.001) and former smokers (1.50; 1.12–2.01, p=0.007) had increased hazard of non-cardiovascular death. Kidney allograft failure was more likely in current smokers than in either former or never smokers (3.5, 2.1 and 2.0 per 100 patient-years, p<0.001, adjusted hazard ratio 1.49 and 1.05, respectively).

Conclusion

Continued smoking was associated with >100% increased risk of non-cardiovascular death, 70% greater risk of all-cause mortality and a 50% greater risk of graft loss, a risk not seen in former smokers. These findings confirm previous non-adjudicated observations that smoking is associated with adverse clinical outcomes and suggest that more emphasis should be placed on smoking cessation prior to kidney transplantation.

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.

Infection and Malignancy Outweigh Cardiovascular Mortality in Kidney Transplant Recipients: Post Hoc Analysis of the FAVORIT Trial

OBJECTIVE

Now that long-term survival after successful renal transplantation is no longer limited by excessive cardiovascular risk, the primary care physician should consider that infection and malignancy are leading noncardiovascular causes of death even in the recipient with diabetes.

METHODS

We accessed the National Institutes of Health-sponsored Folic Acid for Vascular Outcome Reduction in Transplantation (FAVORIT) study population (4010 renal transplant recipients with elevated homocysteine levels) studied to determine whether folate and B12 supplementation would reduce cardiovascular end points. This trial had a null result. Patients were classified as being nondiabetic or having type 1 or type 2 diabetes.

RESULTS

We report an excess (cardiovascular and noncardiovascular) 6-year mortality risk associated with the presence of diabetes mellitus. Two thirds of fatal events in our renal transplant recipients were centrally adjudicated as noncardiovascular. The incidence of noncardiovascular death was 70% higher in the diabetic patient cohort than in the nondiabetic cohort.

CONCLUSIONS

These results demonstrate that infection (but not malignancy) risks are far higher in diabetic than nondiabetic immunosuppressed individuals (although noncardiovascular death rate in nondiabetic individuals also exceeded cardiovascular deaths) and may play a larger role in the excess mortality populations than previously thought. Given that follow-up in this study was 4 to 10 years after allograft surgery, there was a lesser degree of acute rejection requiring high-dose immunosuppression than in the initial postallograft years. This unique perspective allows transplant recipients to return to primary physicians when taking low doses of immunosuppressive agents and provides focus for follow-up care.

Role of B and T Lymphocyte Attenuator in Renal Transplant Recipients with Biopsy-Proven Acute Rejection

Background

Acute rejection is a common predisposing cause of allograft dysfunction in kidney transplantation. Recently, the B and T lymphocyte attenuator (BTLA)/herpes virus entry mediator (HVEM)/lymphotoxin (LIGHT)/CD160 pathway was found to be potentially involved in the regulation of T cell activation. This could mean that this pathway is involved in graft rejection in kidney transplantation; the present study aimed to explore this possibility.

Material/Methods

The expression of BTLA, HVEM, LIGHT and CD160 on peripheral CD4+, CD8+ and CD19+ lymphocytes were analyzed by flow cytometry in recipients with biopsy-proven acute rejection (BPAR) or stable allograft function, as well as in healthy volunteers. Moreover, we performed HE staining and immunohistochemical staining to assess the expression of BTLA and HVEM in kidney samples from recipients with BPAR and patients who underwent the surgery of radical nephrectomy.

Results

We observed the significantly lower expression of BTLA on CD4+ T cells in recipients from the BPAR group than in recipients from the stable group. The expression of BTLA on CD8+ T cells among recipients both from the BPAR and stable group was statistically increased than that in the healthy volunteers. A significant difference in the expression of CD160 in the stable group was found when compared with the BPAR group or control group. Moreover, there was no significance in the expression of HVEM, LIGHT or CD160 on other subtypes of T cells between the 3 groups or in the expression of BTLA on CD4+ T cells between the BPAR and control group.

Conclusions

The findings indicate that the BTLA/HVEM pathway does be involved in pathogenesis of acute rejection following kidney transplantation, as well as the induction of transplant tolerance. This pathway may therefore be a useful target for therapy against acute rejection after kidney transplantation.

Outcomes in patients with diabetes 10 years after liver transplantation

BACKGROUND

There are discrepancies between studies regarding the effect of diabetes mellitus on morbidity and mortality in patients undergoing liver transplantation. The aim of the present study was to compare mortality, risk of liver graft rejection, and cardiovascular events in patients with and without diabetes undergoing liver transplantation over a 10-year follow-up period.

METHODS

A retrospective study was performed on 183 patients who underwent liver transplantation in 2005 and 2006. Mortality and morbidity data were collected until 2016, including information on mortality and survival time, graft rejection and graft survival time, coronary heart disease, stroke, and peripheral arterial ischemia.

RESULTS

During the follow-up, 41.3% and 27.8% of patients in the groups with and without diabetes, respectively, died. A trend for lower survival time was observed in patients with diabetes, although this effect was not confirmed by the Cox regression model. There was an increased risk of graft rejection in the group with diabetes compared with the group without diabetes ( P  < 0.001). In the survival analysis, diabetes was associated with reduced graft survival time ( P  = 0.001). Cardiovascular events were also more likely in the group with diabetes ( P  = 0.005).

CONCLUSIONS

In the present study diabetes was associated with a higher risk of liver graft rejection and cardiovascular events. There was also a trend for higher mortality, although the effect was not statistically significant. These findings suggest that patients with diabetes require a more rigorous pretransplant evaluation and closer monitoring after transplantation in order to try to reduce associated complications.

Does diabetes impact therapeutic immunomodulation therapy decisions for kidney transplant recipients? Data from the Folic Acid for Vascular Outcome Reduction in Transplant (FAVORIT) trial

Although survival has improved for kidney transplant recipients over the past several decades, long-term survival in diabetic cohorts still is significantly less than that of non-diabetic cohorts. We hypothesized that among stable kidney transplant recipients, there might be differences between subgroups with and without diabetes with respect to prevalence of prior cardiovascular events and post-transplant antihypertensive and immunosuppressive therapy. We performed a post hoc analysis of participants in the Folic Acid for Vascular Outcome Reduction in Transplant (FAVORIT) trial, a multicenter international trial of 4110 prevalent kidney transplant recipients enrolled from 2002 to 2007 evaluating the effect of homocysteine-lowering vitamin therapy on cardiovascular outcomes. There were 2447 participants without diabetes, 166 with type 1 diabetes, and 1447 with type 2 diabetes at study entry, which occurred on average 4 years post-transplant. Recipients with diabetes had a greater prevalence of prior cardiovascular events, were more likely to have required multiple medications to control hypertension, and were more likely to have received tacrolimus as opposed to cyclosporine than the non-diabetic transplant recipients (all p<0.001). The effect of differences in treatment of non-diabetic vs diabetic cohorts after stable renal transplantation upon outcomes has not yet been studied and could provide additional information that might lead to improved care.

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.

Behavioral Modification of Intraoperative Hyperglycemia Management with a Novel Real-time Audiovisual Monitor

BACKGROUND

Hyperglycemia, defined as blood glucose (BG) levels above 200 mg/dl (11.1 mM), is associated with increased postoperative morbidity. Yet, the treatment standard for intraoperative glycemic control is poorly defined for noncardiac surgery. Little is known of the interindividual treatment variability or methods to modify intraoperative glycemic management behaviors. AlertWatch (AlertWatch, USA) is a novel audiovisual alert system that serves as a secondary patient monitor for use in operating rooms. The authors evaluated the influence of use of AlertWatch on intraoperative glycemic management behavior.

METHODS

AlertWatch displays historical patient data (risk factors and laboratory results) from multiple networked information systems, combined with the patient's live physiologic data. The authors extracted intraoperative data for 19 months to evaluate the relationship between AlertWatch usage and initiation of insulin treatment for hyperglycemia. Outcome associations were adjusted for physical status, case duration, procedural complexity, emergent procedure, fasting BG value, home insulin therapy, patient age, and primary anesthetist.

RESULTS

Overall, 2,341 patients had documented intraoperative hyperglycemia. Use of AlertWatch (791 of 2,341; 33.5%) was associated with 55% increase in insulin treatment (496 of 791 [62.7%] with and 817 of 1,550 [52.7%] without AlertWatch; adjusted odds ratio [95% CI], 1.55 [1.23 to 1.95]; P < 0.001) and 44% increase in BG recheck after insulin administration (407 of 791 [51.5%] with AlertWatch and 655 of 1,550 [42.3%] in controls; adjusted odds ratio [95% CI], 1.44 [1.14 to 1.81]; P = 0.002).

CONCLUSION

AlertWatch is associated with a significant increase in desirable intraoperative glycemic management behavior and may help achieve tighter intraoperative glycemic control.