Posttransplantation diabetes: a systematic review of the literature

Steroid-tacrolimus drug-drug interaction and the effect of CYP3A genotypes

AIMS

Tacrolimus, metabolized by CYP3A4 and CYP3A5 enzymes, is susceptible to drug-drug interactions (DDI). Steroids induce CYP3A genes to increase tacrolimus clearance, but the effect is variable. We hypothesized that the extent of the steroid-tacrolimus DDI differs by CYP3A4/5 genotypes.

METHODS

Kidney transplant recipients (n = 2462) were classified by the number of loss of function alleles (LOF) (CYP3A5*3, *6 and *7 and CYP3A4*22) and steroid use at each tacrolimus trough in the first 6 months post-transplant. A population pharmacokinetic analysis was performed by nonlinear mixed-effect modelling (NONMEM) and stepwise covariate modelling to define significant covariates affecting tacrolimus clearance. A stochastic simulation was performed and translated into a Shiny application with the mrgsolve and Shiny packages in R.

RESULTS

Steroids were associated with modestly higher (3%-11.8%) tacrolimus clearance. Patients with 0-LOF alleles receiving steroids showed the greatest increase (11.8%) in clearance compared to no steroids, whereas those with 2-LOFs had a negligible increase (2.6%) in the presence of steroids. Steroid use increased tacrolimus clearance by 5% and 10.3% in patients with 1-LOF and 3/4-LOFs, respectively.

CONCLUSIONS

Steroids increase the clearance of tacrolimus but vary slightly by CYP3A genotype. This is important in individuals of African ancestry who are more likely to carry no LOF alleles, may more commonly receive steroid treatment, and will need higher tacrolimus doses.

Multifaceted relationship between diabetes and kidney diseases: Beyond diabetes

Diabetes mellitus is one of the most common causes of chronic kidney disease. Kidney involvement in patients with diabetes has a wide spectrum of clinical presentations ranging from asymptomatic to overt proteinuria and kidney failure. The development of kidney disease in diabetes is associated with structural changes in multiple kidney compartments, such as the vascular system and glomeruli. Glomerular alterations include thickening of the glomerular basement membrane, loss of podocytes, and segmental mesangiolysis, which may lead to microaneurysms and the development of pathognomonic Kimmelstiel-Wilson nodules. Beyond lesions directly related to diabetes, awareness of the possible coexistence of nondiabetic kidney disease in patients with diabetes is increasing. These nondiabetic lesions include focal segmental glomerulosclerosis, IgA nephropathy, and other primary or secondary renal disorders. Differential diagnosis of these conditions is crucial in guiding clinical management and therapeutic approaches. However, the relationship between diabetes and the kidney is bidirectional; thus, new-onset diabetes may also occur as a complication of the treatment in patients with renal diseases. Here, we review the complex and multifaceted correlation between diabetes and kidney diseases and discuss clinical presentation and course, differential diagnosis, and therapeutic oppor-tunities offered by novel drugs.

Newly developed sarcopenia after liver transplantation, determined by a fully automated 3D muscle volume estimation on abdominal CT, can predict post-transplant diabetes mellitus and poor survival outcomes

BACKGROUND

Loss of muscle mass is the most common complication of end-stage liver disease and negatively affects outcomes for liver transplantation (LT) recipients. We aimed to determine the prognostic value of a fully automated three-dimensional (3D) muscle volume estimation using deep learning algorithms on abdominal CT in patients who underwent liver transplantation (LT).

METHODS

This retrospective study included 107 patients who underwent LT from 2014 to 2015. Serial CT scans, including pre-LT and 1- and 2-year follow-ups were performed. From the CT scans, deep learning-based automated body composition segmentation software was used to calculate muscle volumes in 3D. Sarcopenia was calculated by dividing average skeletal muscle area by height squared. Newly developed-(ND) sarcopenia was defined as the onset of sarcopenia 1 or 2 years after LT in patients without a history of sarcopenia before LT. Patients' clinical characteristics, including post-transplant diabetes mellitus (PTDM) and Model for end-stage liver disease score, were compared according to the presence or absence of sarcopenia after LT. A subgroup analysis was performed in the post-LT sarcopenic group. The Kaplan-Meier method was used for overall survival (OS).

RESULTS

Patients with ND-sarcopenia had poorer OS than those who did not (P = 0.04, hazard ratio [HR], 3.34; 95% confidence interval [CI] 1.05 - 10.7). In the subgroup analysis for post-LT sarcopenia (n = 94), 34 patients (36.2%) had ND-sarcopenia. Patients with ND-sarcopenia had significantly worse OS (P = 0.002, HR 7.12; 95% CI 2.00 - 25.32) and higher PTDM occurrence rates (P = 0.02, HR 4.93; 95% CI 1.18 - 20.54) than those with sarcopenia prior to LT.

CONCLUSION

ND-sarcopenia determined by muscle volume on abdominal CT can predict poor survival outcomes and the occurrence of PTDM for LT recipients.

Association of fasting blood glucose variability with all-cause mortality in heart transplant recipients

BACKGROUND

Fasting blood glucose (FBG) variability, an emerging marker of glycemic control, has been shown to be related to the risk of cardiovascular events and all-cause mortality in subjects with or without diabetes. However, whether FBG variability is independently associated with a higher all-cause mortality in heart transplant recipients remains unknown.

METHODS

We performed a retrospective cohort study including 373 adult recipients who survived for at least 1 year after heart transplantation with a functioning graft and measured FBG more than three times within first year after transplantation. Multivariable adjusted Cox regression analyses were performed to assess the association between FBG variability and all-cause mortality.

RESULTS

Patients were categorized into three groups according to the coefficient of variation of FBG level: ≤7.0%, 7.0%-13.5%, and >13.5%. During a median follow-up of 44.4 months (interquartile range [IQR], 22.6-63.3 months), 31 (8.3%) participants died. In univariate analyses, FBG variability was associated with an increased all-cause mortality (hazard ratio [HR]: 3.00, 95% confidence interval [CI]: 1.67, 5.38; p < .001). This association remained materially unchanged in the multivariable model adjusted for components of demographics, cardiovascular history and lifestyle, hospital information, immunosuppressive therapy, and post-transplant renal function (HR: 2.75, 95% CI: 1.43, 5.28; p = .004).

CONCLUSIONS

After heart transplantation, high FBG variability is strongly and independently associated with an increased risk of all-cause mortality. Our findings suggest that FBG variability is a novel risk factor and prognostic marker for heart transplantation recipients in outpatient clinic.

The effect of PINK1/Parkin pathway on glucose homeostasis imbalance induced by tacrolimus in mouse livers

Treatment using the immunosuppressive drug tacrolimus (TAC) is related to new-onset diabetes after transplantation (NODAT). Previous studies focused mainly on islet β cells in the diabetogenic effect of TAC. Herein, we revealed that NODAT was probably induced by TAC via hepatic insulin resistance. After daily injection of mice with TAC, a glucose metabolism disorder was induced. In addition, TAC decreased the mRNA and protein levels of insulin receptor substrate 2 (IRS2), glucose transporter type 2 (GLUT2), and the phosphorylation of protein kinase B beta (pAKT2), which indicated impaired hepatic insulin signaling. Furthermore, the PTEN-induced novel kinase 1(PINK1)/Parkin pathway was shown to have a key role in the TAC-induced imbalance of hepatic glucose homeostasis. Mechanistic investigations in human hepatic cell lines revealed that TAC stimulated PINK1/Parkin expression and inhibited the expression of insulin signaling related molecules (e.g., IRS2, GLUT2 and pAKT2). Knockdown of hepatic PINK1 regulated downstream molecules of the PINK1/Parkin pathway (GLUT2 and IRS2), which reversed TAC-induced insulin resistance. Thus, in the liver, PINK1/Parkin signaling plays an important role in the TAC-induced imbalance of glucose homeostasis. TAC-induced diabetes might be prevented using Targeted treatment.

Cardiovascular disease risk factors and lifestyle modification strategies after pediatric kidney transplantation: what are we dealing with, and what can we target?

Kidney transplantation in pediatric patients can lead to partial improvement of some of the cardiometabolic parameters that increase the risk for cardiovascular disease (CVD) in patients with chronic kidney disease. However, even after restoration of kidney function, transplant recipients remain at risk for CVD due to the continual presence of traditional and non-traditional risk factors, including the side effects of immunosuppression and chronic inflammation. This educational review describes the prevalence of CVD risk factors in pediatric kidney transplant recipients and presents available evidence for therapeutic lifestyle changes and other non-pharmacologic strategies that can be used to improve traditional and modifiable CVD risk factors. Although trial-grade evidence for interventions that improve CVD in pediatric kidney transplant recipients is limited, potential strategies include lowering dietary sodium and saturated fat intake and increasing physical activity levels. Intensive follow-up may help patients achieve guideline-recommended goals for reducing their overall CVD risk.

Real-life comparison of efficacy and safety profiles of two prolonged-release tacrolimus formulations in de novo kidney transplant recipients: 24 months of follow-up

INTRODUCTION

Calcineurin inhibitors constitute a cornerstone of immunosuppressive therapy in kidney transplant recipients. There are two main formulations of tacrolimus (Tac) which exhibit a prolonged-release mode of action: Advagraf® (MR-4) and Envarsus® (LCPT). However, they are not bioequivalent. Data comparing both once-daily prolonged-release formulations of Tac are insufficient.

OBJECTIVE

The aim of the study was to compare safety and efficacy profiles of once-daily LCPT and MR-4 formulations of tacrolimus in adult kidney transplant recipients.

PATIENTS AND METHODS

An observational, cohort single-center study was performed. One hundred fifteen kidney transplant recipients transplanted between 2016 and 2019 were enrolled to the study (59 vs 56, Envarsus® vs Advagraf®, respectively). Safety and efficacy profiles were assessed.

RESULTS

Patient and graft survival at 12 and 24 months did not differ between the groups. There were no significant differences in serum creatinine at any timepoint. C/D ratio in the LCPT group was significantly higher at 12 and 24 months. Sepsis occurrence was more frequent in MR-4 group at 12 months.

CONCLUSION

Both prolonged-release formulations of tacrolimus are safe and effective in immunosuppressive therapy in kidney transplant recipients.

Characterization, evolution and risk factors of diabetes and prediabetes in a pediatric cohort of renal and liver transplant recipients

BACKGROUND

Hyperglycemia (HG) and prediabetes are rarely sought in pediatric liver (LT) and renal (RT) transplantation, yet their presence indicates a high risk of diabetes and cardiovascular disease. The objectives of our DIABGRAFT study were to retrospectively (rDIABGRAFT) and longitudinally (pDIABGRAFT) characterize HG and (pre)diabetes in a cohort of children with LT or/and RT.

METHODS

We retrospectively analyzed risk factors of HG from 195 children with LT from 2012 to 2019 and twenty children with RT from 2005 to 2019 at Cliniques universitaires Saint-Luc. In addition, we prospectively followed four LT and four RT children to evaluate the evolution of their glucose metabolism.

RESULTS

Our rDIABGRAFT study showed that 25% and 35% of LT and RT children respectively presented transient HG and 20% of RT developed diabetes. The occurrence of HG was associated with the use of glucocorticoids and with acute events as graft rejection and infection. In our pDIABGRAFT cohort, biological markers of diabetes were in the normal range for HbA_1C, fasting glucose and insulin levels. However, oral glucose tolerance test and glucose sensors showed insulin resistance, impaired glucose tolerance and HG in the post-prandial afternoon period.

CONCLUSION

Our study shows that children with LT and RT were more at risk of developing HG when glucocorticoids were required and that HbA_1C and fasting glucose lack sensitivity for early detection of glucose intolerance. Also, measurement of glycemia immediately after the transplantation and in postprandial period is key to detect dysglycemia since insulin resistance prevailed in our cohort.

CLINICALTRIALSGOV ID

NCT05464043.

Clinical outcomes of posttransplantation diabetes mellitus in kidney transplantation recipients: a nationwide population-based cohort study in Korea

Posttransplantation diabetes mellitus (PTDM) is an important metabolic complication after KT that causes graft failure and cardiovascular complications in kidney transplantation (KT) recipients. Using the national claim data of South Korea, 7612 KT recipients between 2009 and 2017 were analyzed. PTDM was defined as a consecutive 30-day prescription history of antidiabetic medication after KT. Among these patients, 24.7% were diagnosed with PTDM, and 51.9% were diagnosed within 6 months after KT. Compared to patients without PTDM, those with PTDM were older, more likely to be men, more likely to be diagnosed with hypertension and cardio-cerebrovascular disease, and experienced more rejection episodes requiring high-dose steroid treatment after KT. During the follow-up, 607 DCGFs, 230 DWGFs, 244 MACEs, and 260 all-cause mortality events occurred. Patients with PTDM showed a higher risk of DCGF (adjusted hazard ratio [aHR] 1.49; 95% confidence interval [CI] 1.22-1.82; P < 0.001) and MACEs (aHR 1.76; 95% CI 1.33-2.31; P < 0.001) than patients without PTDM. The risks for all clinical outcomes were higher in the insulin group than in the non-use insulin group. PTDM in KT recipients resulted in both worse allograft and patient outcomes represented by DCGF and MACE, especially in patients needing insulin treatment.

Donor and recipient polygenic risk scores influence the risk of post-transplant diabetes

Post-transplant diabetes mellitus (PTDM) reduces allograft and recipient life span. Polygenic risk scores (PRSs) show robust association with greater risk of developing type 2 diabetes (T2D). We examined the association of PTDM with T2D PRS in liver recipients (n = 1,581) and their donors (n = 1,555), and kidney recipients (n = 2,062) and their donors (n = 533). Recipient T2D PRS was associated with pre-transplant T2D and the development of PTDM. T2D PRS in liver donors, but not in kidney donors, was an independent risk factor for PTDM development. The inclusion of a combined liver donor and recipient T2D PRS significantly improved PTDM prediction compared with a model that included only clinical characteristics: the area under the curve (AUC) was 67.6% (95% confidence interval (CI) 64.1-71.1%) for the combined T2D PRS versus 62.3% (95% CI 58.8-65.8%) for the clinical characteristics model (P = 0.0001). Liver recipients in the highest quintile of combined donor and recipient T2D PRS had the greatest risk of PTDM, with an odds ratio of 3.22 (95% CI 2.07-5.00) (P = 1.92 × 10^-7) compared with those in the lowest quintile. In conclusion, T2D PRS identifies transplant candidates with high risk of PTDM for which pre-emptive diabetes management and donor selection may be warranted.

Cardiometabolic and Kidney Protection in Kidney Transplant Recipients With Diabetes: Mechanisms, Clinical Applications, and Summary of Clinical Trials

Kidney transplantation is the therapy of choice for patients with end-stage renal disease. Preexisting diabetes is highly prevalent in kidney transplant recipients (KTR), and the development of posttransplant diabetes is common because of a number of transplant-specific risk factors such as the use of diabetogenic immunosuppressive medications and posttransplant weight gain. The presence of pretransplant and posttransplant diabetes in KTR significantly and variably affect the risk of graft failure, cardiovascular disease (CVD), and death. Among the many available therapies for diabetes, there are little data to determine the glucose-lowering agent(s) of choice in KTR. Furthermore, despite the high burden of graft loss and CVD among KTR with diabetes, evidence for strategies offering cardiovascular and kidney protection is lacking. Recent accumulating evidence convincingly shows glucose-independent cardiorenal protective effects in non-KTR with glucose-lowering agents, such as sodium-glucose cotransporter-2 inhibitors and glucagon-like peptide-1 receptor agonists. Therefore, our aim was to review cardiorenal protective strategies, including the evidence, mechanisms, and rationale for the use of these glucose-lowering agents in KTR with diabetes.

Remnant lipoprotein cholesterol is associated with incident new onset diabetes after transplantation (NODAT) in renal transplant recipients: results of the TransplantLines Biobank and cohort Studies

Background

New onset diabetes after transplantation (NODAT) is a frequent and serious complication of renal transplantation resulting in worse graft and patient outcomes. The pathophysiology of NODAT is incompletely understood, and no prospective biomarkers have been established to predict NODAT risk in renal transplant recipients (RTR). The present work aimed to determine whether remnant lipoprotein (RLP) cholesterol could serve as such a biomarker that would also provide a novel target for therapeutic intervention.

Methods

This longitudinal cohort study included 480 RTR free of diabetes at baseline. 53 patients (11%) were diagnosed with NODAT during a median [interquartile range, IQR] follow-up of 5.2 [4.1–5.8] years. RLP cholesterol was calculated by subtracting HDL and LDL cholesterol from total cholesterol values (all directly measured).

Results

Baseline remnant cholesterol values were significantly higher in RTR who subsequently developed NODAT (0.9 [0.5–1.2] mmol/L vs. 0.6 [0.4–0.9] mmol/L, p = 0.001). Kaplan-Meier analysis showed that higher RLP cholesterol values were associated with an increased risk of incident NODAT (log rank test, p < 0.001). Cox regression demonstrated a significant longitudinal association between baseline RLP cholesterol levels and NODAT (HR, 2.27 [1.64–3.14] per 1 SD increase, p < 0.001) that remained after adjusting for plasma glucose and HbA1c (p = 0.002), HDL and LDL cholesterol (p = 0.008) and use of immunosuppressive medication (p < 0.001), among others. Adding baseline remnant cholesterol to the Framingham Diabetes Risk Score significantly improved NODAT prediction (change in C-statistic, p = 0.01).

Conclusions

This study demonstrates that baseline RLP cholesterol levels strongly associate with incident NODAT independent of several other recognized risk factors.

Predictors of New-onset Diabetes After Kidney Transplantation During 2019-nCoV Pandemic: A Unison of Frequentist Inference and Narrow AI

BACKGROUND: New-onset diabetes after kidney transplant (NODAT) is a severe metabolic complication that frequently occurs in recipients following transplantation. AIM: The study aims to verify NODAT, compare cases and non-cases of this entity, and explore potential predictors in recipients within 1 year following kidney transplantation. METHODS: The research is a retrospective study of 90 renal transplant recipients (n = 90). Demographic factors and clinical aspects were analyzed using non-Bayesian statistics and machine learning (ML). The clinical aspects included the glycated hemoglobin (HbA1c) level, associated viral infections (hepatitis B virus [HBV], hepatitis C virus [HCV], and cytomegalovirus [CMV]), prior kidney transplant, hemodialysis status, body mass index (BMI) at transplant time, and 3 months later, primary causes of renal failure, and post-transplant therapeutics. All individuals were on cyclosporine and prednisolone treatment. RESULTS: The mean age was 39 (±1.5) years; recipients included 27 females (30%) and 63 males (70%). Donor type was live related (16, 17.8%) or live unrelated (74, 82.2%); 27 recipients (30%) had O+ blood group, while 70% belonged to other groups. Thirteen recipients (14.4%) were not on dialysis. Only 32 individuals (35.6%) developed NODAT. Concerning virology, confirmed by real-time polymerase chain reaction before transplantation, 19 recipients (21.1%) were CMV positive, 9 (10%) were HCV positive, and 2 (2.2%) had HBV. CONCLUSIONS: In reconciliation with frequentist statistics, the dual ML model validated several predictors that either negatively (protective) or positively (harmful) influenced HbA1c level, the majority of which were significant at 95% confidence interval. Individuals who are HCV and CMV positive are predicted to develop NODAT. Further, older individuals, with blood group O+ve, prior history of hemodialysis, a relatively high BMI before the transplant, and receiving higher doses of prednisolone following the transplant are more likely to develop NODAT. The current study represents the first research from Iraq to explore NODAT predictors among kidney transplant recipients using frequentist statistics and artificial intelligence models.

Management of long-term cardiovascular risk factors post organ transplant

PURPOSE OF REVIEW

Cardiovascular disease is one of the leading causes of death in solid organ transplant (SOT) recipients. Early identification of cardiovascular risk factors and their adequate management in this population is key for prevention and improved outcomes.

RECENT FINDINGS

Approximately 80% of SOT present one or more cardiovascular risk factors, with increasing prevalence with time posttransplantation. They are due to the interplay of pretransplant conditions and metabolic consequences of immunosuppressive agents, mainly corticosteroids and calcineurin inhibitors. Among the pharmacological management strategies, statins have shown an important protective effect in SOT.

SUMMARY

Strict surveillance of cardiovascular risk factors is recommended in SOT due to their high prevalence and prognostic implications. Further studies on the best managements strategies in this population are needed.

Association of diuretic use with increased risk for long-term post-transplantation diabetes mellitus in kidney transplant recipients

Background

Post-transplantation diabetes mellitus (PTDM) is a major clinical problem in kidney transplant recipients (KTRs). Diuretic-induced hyperglycaemia and diabetes have been described in the general population. We aimed to investigate whether diuretics also increase PTDM risk in KTRs.

Methods

We included 486 stable outpatient KTRs (with a functioning graft ≥1 year) without diabetes from a prospective cohort study. Participants were classified as diuretic users and non-users based on their medication use verified by medical records.

Results

At the baseline study, 168 (35%) KTRs used a diuretic (thiazide, n = 74; loop diuretic, n = 76; others, n = 18) and 318 KTRs did not use a diuretic. After 5.2 years [interquartile range (IQR) 4.0‒5.9] of follow up, 54 (11%) KTRs developed PTDM. In Cox regression analyses, diuretic use was associated with incident PTDM, independent of age, sex, fasting plasma glucose (FPG) and haemoglobin A_1c (HbA_1c) {hazard ratio [HR] 3.28 [95% confidence interval (CI) 1.84–5.83]; P <0.001}. Further adjustment for potential confounders, including lifestyle, family history of cardiovascular disease, use of other medication, kidney function, transplantation-specific parameters, BMI, lipids and blood pressure did not materially change the association. Moreover, in Cox regression analyses, both thiazide and loop diuretics associated with the development of PTDM, independent of age, sex, FPG and HbA_1c [HR 2.70 (95% CI 1.24–5.29); P = 0.012 and HR 5.08 (95% CI 2.49–10.34); P <0.001), respectively].

Conclusions

This study demonstrates that diuretics overall are associated with an increased risk of developing PTDM in KTRs, independent of established risk factors for PTDM development. The association was present for both thiazide and loop diuretics.

Early Post-Renal Transplant Hyperglycemia

CONTEXT

Though posttransplant diabetes mellitus (PTDM, occurring > 45 days after transplantation) and its complications are well described, early post-renal transplant hyperglycemia (EPTH) (< 45 days) similarly puts kidney transplant recipients at risk of infections, rehospitalizations, and graft failure and is not emphasized much in the literature. Proactive screening and management of EPTH is required given these consequences.

OBJECTIVE

The aim of this article is to promote recognition of early post-renal transplant hyperglycemia, and to summarize available information on its pathophysiology, adverse effects, and management.

METHODS

A PubMed search was conducted for "early post-renal transplant hyperglycemia," "immediate posttransplant hyperglycemia," "post-renal transplant diabetes," "renal transplant," "diabetes," and combinations of these terms. EPTH is associated with significant complications including acute graft failure, rehospitalizations, cardiovascular events, PTDM, and infections.

CONCLUSION

Patients with diabetes experience better glycemic control in end-stage renal disease (ESRD), with resurgence of hyperglycemia after kidney transplant. Patients with and without known diabetes are at risk of EPTH. Risk factors include elevated pretransplant fasting glucose, diabetes, glucocorticoids, chronic infections, and posttransplant infections. We find that EPTH increases risk of re-hospitalizations from infections (cytomegalovirus, possibly COVID-19), acute graft rejections, cardiovascular events, and PTDM. It is essential, therefore, to provide diabetes education to patients before discharge. Insulin remains the standard of care while inpatient. Close follow-up after discharge is recommended for insulin adjustment. Some agents like dipeptidyl peptidase-4 inhibitors and glucagon-like peptide-1 receptor agonists have shown promise. The tenuous kidney function in the early posttransplant period and lack of data limit the use of sodium-glucose cotransporter 2 inhibitors. There is a need for studies assessing noninsulin agents for EPTH to decrease risk of hypoglycemia associated with insulin and long-term complications of EPTH.

Posttransplant Diabetes Mellitus and Immunosuppression Selection in Older and Obese Kidney Recipients

Rationale & Objective

Posttransplant diabetes mellitus (DM) after kidney transplantation increases morbidity and mortality, particularly in older and obese recipients. We aimed to examine the impact of immunosuppression selection on the risk of posttransplant DM among both older and obese kidney transplant recipients.

Study Design

Retrospective database study.

Setting & Participants

Kidney-only transplant recipients aged ≥18 years from 2005 to 2016 in the United States from US Renal Data System records, which integrate Organ Procurement and Transplantation Network/United Network for Organ Sharing records with Medicare billing claims.

Exposures

Various immunosuppression regimens in the first 3 months after transplant.

Outcomes

Development of DM >3 months-to-1 year posttransplant.

Analytical Approach

We used multivariable Cox regression to compare the incidence of posttransplant DM by immunosuppression regimen with the reference regimen of thymoglobulin (TMG) or alemtuzumab (ALEM) with tacrolimus + mycophenolic acid + prednisone using inverse propensity weighting.

Results

12.7% of kidney transplant recipients developed posttransplant DM with higher incidences in older (≥55 years vs <55 years: 16.7% vs 10.1%) and obese (body mass index [BMI] ≥ 30 kg/m² vs BMI < 30 kg/m²: 17.1% vs 10.9%) patients. The incidence of posttransplant DM was lower with steroid avoidance [TMG/ALEM + no prednisone (8.4%) and IL2rAb + no prednisone (9.7%)] than TMG/ALEM with triple therapy (13.1%). After adjustment for donor and recipient characteristics, TMG/ALEM with steroid avoidance was beneficial for all groups [age < 55 years: adjusted HR (aHR), 0.63 (95% confidence interval [CI], 0.54-0.72); age ≥ 55 years: aHR, 0.69 (95% CI, 0.60-0.79); BMI < 30 kg/m²: aHR, 0.69 (95% CI, 0.60-0.78); BMI ≥ 30 kg/m²: aHR, 0.67 (95% CI, 0.57-0.79)]. However, IL2rAb with steroid avoidance was beneficial only for older patients (aHR, 0.76; 95% CI, 0.58-0.99) and for those with BMI < 30 kg/m² (aHR, 0.63; 95% CI, 0.46-0.87).

Limitations

Retrospective study and lacked data on immunosuppression levels.

Conclusions

The beneficial impact of steroid avoidance using tacrolimus on posttransplant DM appears to differ by patient age and induction regimen.

Surgical Management of Lower Extremity Wounds in the Solid Organ Transplant Patient Population: Surgeon Beware

Objective: To evaluate our institutional outcomes of surgical management of lower extremity (LE) wounds in the solid organ transplant recipient population. Approach: An 8-year retrospective review was conducted for all solid organ transplantation (SOT) recipients with LE wounds necessitating surgical management at our tertiary limb salvage center. Outcomes of interest included wound healing, surgical treatment, progression to amputation, and amputation level. Factors contributing to amputation progression were analyzed. The article adheres to the Strengthening the Reporting of Observational Studies in Epidemiology statement. Results: Sixty-four SOT recipients underwent surgical management for their LE wounds between 2010 and 2018. Median number of surgeries per patient was 5 (interquartile range = 2-8); 47 of 64 patients (73.4%) underwent amputation, and 17 of 64 patients (26.6%) underwent nonamputation surgical management. In the amputation group, the majority of primary amputations were minor (42/47, 89.4%); 24 of 42 (57.1%) patients progressed to a higher amputation level, 16 of 42 (38.1%) healed after their index procedure, and 2 of 42 (4.8%) were lost to follow-up (LTFU) after their primary minor amputation. Five of 47 (10.6%) patients undergoing amputations required primary below-knee amputations. In the nonamputation group, 15 of 17 (88.2%) healed, 1 of 17 (5.9%) expired, and 1 of 17 (5.9%) was LTFU. Innovation: To identify the outcomes of patients undergoing surgical management for LE wounds after SOT and elucidate clinical factors that impact the rate of limb salvage. Conclusions: This is the first comprehensive analysis of LE wounds in the transplant population. Our analysis indicates high rates of failed minor amputation, and frequent progression to major amputation in SOT patients. Preexisting comorbidities and immunosuppressive regimens complicate limb salvage; therefore, further research is warranted to optimize surgical LE wound management in this population.

Effect of Early Steroid Withdrawal on Posttransplant Diabetes Among Kidney Transplant Recipients Differs by Recipient Age

Supplemental Digital Content is available in the text.

Background.

Posttransplant diabetes (PTD), a major complication after kidney transplantation (KT), is often attributable to immunosuppression. The risk of PTD may increase with more potent steroid maintenance and older recipient age.

Methods.

Using United States Renal Data System data, we studied 12 488 adult first-time KT recipients (2010–2015) with no known pre-KT diabetes. We compared the risk of PTD among recipients who underwent early steroid withdrawal (ESW) versus continued steroid maintenance (CSM) using Cox regression with inverse probability weighting to adjust for confounding. We tested whether the risk of PTD resulting from ESW differed by recipient age (18–29, 30–54, and ≥55 y).

Results.

Of 12 488, 28.3% recipients received ESW. The incidence rate for PTD was 13 per 100 person-y and lower among recipients who received ESW (11 per 100 person-y in ESW; 14 per 100 person-y in CSM). Overall, ESW was associated with lower risk of PTD compared with CSM (adjusted hazard ratio [aHR] = _0.720.79_0.86), but the risk differed by recipient age (P_interaction = 0.09 for comparison between recipients aged 18–29 and those aged 30–54; P_interaction = 0.01 for comparison between recipients aged 18–29 and those aged ≥55). ESW was associated with lower risk of PTD among recipients aged ≥55 (aHR = _0.620.71_0.81) and those aged 30–54 (aHR = _0.730.83_0.95), but not among recipients aged 18–29 (aHR = _0.811.18_1.72). Although recipients who received ESW had a higher risk of acute rejection across the age groups (adjusted odds ratio = _1.011.17_1.34), recipients with no PTD had a lower risk of mortality (aHR = _0.580.66_0.74).

Conclusions.

The beneficial association of ESW with decreased PTD was more pronounced among recipients aged ≥55, supporting an age-specific assessment of the risk-benefit balance regarding ESW.

Global Epidemiology, Health Outcomes, and Treatment Options for Patients With Type 2 Diabetes and Kidney Failure

The burden of type 2 diabetes and related complications has steadily increased over the last few decades and is one of the foremost global public health threats in the 21st century. Diabetes is one of the leading causes of chronic kidney disease and kidney failure and is an important contributor to the cardiovascular morbidity and mortality in this population. In addition, up to one in three patients who have received kidney transplants develop post-transplant diabetes, but the management of this common complication continues to pose a significant challenge for clinicians. In this review, we will describe the global prevalence and temporal trend of kidney failure attributed to diabetes mellitus in both developing and developed countries. We will examine the survival differences between treated kidney failure patients with and without type 2 diabetes, focusing on the survival differences in those on maintenance dialysis or have received kidney transplants. With the increased availability of novel hypoglycemic agents, we will address the potential impacts of these novel agents in patients with diabetes and kidney failure and in those who have developed post-transplant diabetes.

Obesity and Post-Transplant Diabetes Mellitus in Kidney Transplantation

Worldwide, the prevalence obesity, diabetes, and chronic kidney disease is increasing apace. The relationship between obesity and chronic kidney disease is multidimensional, especially when diabetes is also considered. The optimal treatment of patients with chronic kidney disease includes the need to consider weight loss as part of the treatment. The exact relationship between obesity and kidney function before and after transplantation is not as clear as previously imagined. Historically, patients with obesity had worse outcomes following kidney transplantation and weight loss before surgery was encouraged. However, recent studies have found less of a correlation between obesity and transplant outcomes. Transplantation itself is also a risk factor for developing diabetes, a condition known as post-transplant diabetes mellitus, and is related to the use of immunosuppressive medications and weight gain following transplantation. Newer classes of anti-diabetic medications, namely SGLT-2 inhibitors and GLP-1 agonists, are increasingly being recognized, not only for their ability to control diabetes, but also for their cardio and renoprotective effects. This article reviews the current state of knowledge on the management of obesity and post-transplant diabetes mellitus for kidney transplant patients.

Post-transplant Diabetes Mellitus in Kidney Transplant Recipients: A Multicenter Study

Background

De novo post-transplant diabetes mellitus (PTDM) is a common complication after kidney transplant (KT). Most recent studies are single center with various approaches to outcome ascertainment.

Methods

In a multicenter longitudinal cohort of 632 nondiabetic adult kidney recipients transplanted in 2010-2013, we ascertained outcomes through detailed chart review at 13 centers. We hypothesized that donor characteristics, such as sex, HCV infection, and kidney donor profile index (KDPI), and recipient characteristics, such as age, race, BMI, and increased HLA mismatches, would affect the development of PTDM among KT recipients. We defined PTDM as hemoglobin A1c ≥6.5%, pharmacological treatment for diabetes, or documentation of diabetes in electronic medical records. We assessed PTDM risk factors and evaluated for an independent time-updated association between PTDM and graft failure using regression.

Results

Mean recipient age was 52±14 years, 59% were male, 49% were Black. Cumulative PTDM incidence 5 years post-KT was 29% (186). Independent baseline PTDM risk factors included older recipient age (P<0.001) and higher BMI (P=0.006). PTDM was not associated with all-cause graft failure (adjusted hazard ratio (aHR), 1.10; 95% CI, 0.78 to 1.55), death-censored graft failure (aHR, 0.85; 95% CI, 0.53 to 1.37), or death (aHR, 1.31; 95% CI, 0.84 to 2.05) at median follow-up of 6 (interquartile range, 4.0-6.9) years post-KT. Induction and maintenance immunosuppression were not different between patients who did and did not develop PTDM.

Conclusions

PTDM occurred commonly, and higher baseline BMI was associated with PTDM. PTDM was not associated with graft failure or mortality during the 6-year follow-up, perhaps due to the short follow-up time.

Deep Learning-Based Quantification of Visceral Fat Volumes Predicts Posttransplant Diabetes Mellitus in Kidney Transplant Recipients

Background: Because obesity is associated with the risk of posttransplant diabetes mellitus (PTDM), the precise estimation of visceral fat mass before transplantation may be helpful. Herein, we addressed whether a deep-learning based volumetric fat quantification on pretransplant computed tomographic images predicted the risk of PTDM more precisely than body mass index (BMI).

Methods: We retrospectively included a total of 718 nondiabetic kidney recipients who underwent pretransplant abdominal computed tomography. The 2D (waist) and 3D (waist or abdominal) volumes of visceral, subcutaneous, and total fat masses were automatically quantified using the deep neural network. The predictability of the PTDM risk was estimated using a multivariate Cox model and compared among the fat parameters using the areas under the receiver operating characteristic curves (AUROCs).

Results: PTDM occurred in 179 patients (24.9%) during the median follow-up period of 5 years (interquartile range, 2.5–8.6 years). All the fat parameters predicted the risk of PTDM, but the visceral and total fat volumes from 2D and 3D evaluations had higher AUROC values than BMI did, and the best predictor of PTDM was the 3D abdominal visceral fat volumes [AUROC, 0.688 (0.636–0.741)]. The addition of the 3D abdominal VF volume to the model with clinical risk factors increased the predictability of PTDM, but BMI did not.

Conclusions: A deep-learning based quantification of visceral fat volumes on computed tomographic images better predicts the risk of PTDM after kidney transplantation than BMI.

Diabetes and Cardiovascular Risk in Renal Transplant Patients

End-stage kidney disease (ESKD) is a main public health problem, the prevalence of which is continuously increasing worldwide. Due to adverse effects of renal replacement therapies, kidney transplantation seems to be the optimal form of therapy with significantly improved survival, quality of life and diminished overall costs compared with dialysis. However, post-transplant patients frequently suffer from post-transplant diabetes mellitus (PTDM) which an important risk factor for cardiovascular and cardiovascular-related deaths after transplantation. The management of post-transplant diabetes resembles that of diabetes in the general population as it is based on strict glycemic control as well as screening and treatment of common complications. Lifestyle interventions accompanied by the tailoring of immunosuppressive regimen may be of key importance to mitigate PTDM-associated complications in kidney transplant patients. More transplant-specific approach can include the exchange of tacrolimus with an alternative immunosuppressant (cyclosporine or mammalian target of rapamycin (mTOR) inhibitor), the decrease or cessation of corticosteroid therapy and caution in the prescribing of diuretics since they are independently connected with post-transplant diabetes. Early identification of high-risk patients for cardiovascular diseases enables timely introduction of appropriate therapeutic strategy and results in higher survival rates for patients with a transplanted kidney.

Current Pharmacological Intervention and Medical Management for Diabetic Kidney Transplant Recipients

Hyperglycemia after kidney transplantation is common in both diabetic and non-diabetic patients. Both pretransplant and post-transplant diabetes mellitus are associated with increased kidney allograft failure and mortality. Glucose management may be challenging for kidney transplant recipients. The pathophysiology and pattern of hyperglycemia in patients following kidney transplantation is different from those with type 2 diabetes mellitus. In patients with pre-existing and post-transplant diabetes mellitus, there is limited data on the management of hyperglycemia after kidney transplantation. The following article discusses the nomenclature and diagnosis of pre- and post-transplant diabetes mellitus, the impact of transplant-related hyperglycemia on patient and kidney allograft outcomes, risk factors and potential pathogenic mechanisms of hyperglycemia after kidney transplantation, glucose management before and after transplantation, and modalities for prevention of post-transplant diabetes mellitus.

Metabolic Consequences of Solid Organ Transplantation

Metabolic complications affect over 50% of solid organ transplant recipients. These include posttransplant diabetes, nonalcoholic fatty liver disease, dyslipidemia, and obesity. Preexisting metabolic disease is further exacerbated with immunosuppression and posttransplant weight gain. Patients transition from a state of cachexia induced by end-organ disease to a pro-anabolic state after transplant due to weight gain, sedentary lifestyle, and suboptimal dietary habits in the setting of immunosuppression. Specific immunosuppressants have different metabolic effects, although all the foundation/maintenance immunosuppressants (calcineurin inhibitors, mTOR inhibitors) increase the risk of metabolic disease. In this comprehensive review, we summarize the emerging knowledge of the molecular pathogenesis of these different metabolic complications, and the potential genetic contribution (recipient +/- donor) to these conditions. These metabolic complications impact both graft and patient survival, particularly increasing the risk of cardiovascular and cancer-associated mortality. The current evidence for prevention and therapeutic management of posttransplant metabolic conditions is provided while highlighting gaps for future avenues in translational research.

Serum uric acid is associated with increased risk of posttransplantation diabetes in kidney transplant recipients: a prospective cohort study

BACKGROUND

Serum uric acid (SUA) is associated with fasting glucose in healthy subjects, and prospective epidemological studies have shown that elevated SUA is associated with increased risk of type 2 diabetes. Whether SUA is independently associated with higher risk of posttransplantation diabetes mellitus (PTDM) in kidney transplant recipients (KTR) remains unknown.

METHODS

We performed a longitudinal cohort study of 524 adult KTR with a functioning graft ≥1-year, recruited at a university setting (2008-2011). Multivariable-adjusted Cox proportional-hazards regression analyses were performed to assess the association between time-updated SUA and risk of PTDM (defined according the American Diabetes Association's diagnostic criteria).

RESULTS

Mean (SD) SUA was 0.43 (0.11) mmol/L at baseline. During 5.3 (IQR, 4.1-6.0) years of follow-up, 52 (10%) KTR developed PTDM. In univariate prospective analyses, SUA was associated with increased risk of PTDM (HR 1.75, 95% CI 1.36-2.26 per 1-SD increment; P < 0.001). This finding remained materially unchanged after adjustment for components of the metabolic syndrome, lifestyle, estimated glomerular filtration rate, immunosuppressive therapy, cytomegalovirus and hepatitis C virus infection (HR 1.89, 95% CI 1.32-2.70; P = 0.001). These findings were consistent in categorical analyses, and robust in sensitivity analyses without outliers.

CONCLUSIONS

In KTR, higher SUA levels are strongly and independently associated with increased risk of PTDM. Our findings are in agreement with accumulating evidence supporting SUA as novel independent risk marker for type 2 diabetes, and extend the evidence, for the first time, to the clinical setting of outpatient KTR.

Sleep-disordered breathing after lung transplantation: An observational cohort study

Data concerning sleep-disordered breathing (SDB) after lung transplantation (LTX) are scarce. This study aims to analyze prevalence, associated factors, and impact on survival of moderate to severe SDB in a large cohort of consecutive LTX patients (n = 219). Patients underwent a diagnostic polysomnography 1 year after LTX. Moderate to severe SDB was present in 57.5% of patients, with the highest prevalence in chronic obstructive pulmonary disease/emphysema (71.1%) and pulmonary fibrosis (65.1%). SDB patients were older, mostly male, and had higher body mass index and neck circumference. Nocturnal diastolic and 24-hour blood pressures were higher in SDB patients. In 45 patients, polysomnography was also performed pre-LTX. Compared to pre-LTX, mean apnea/hypopnea index (AHI) increased significantly after LTX. A significant correlation was seen between lung function parameters and AHI, suggesting a role of decreased caudal traction on the pharynx. Presence of SDB had no impact on mortality or prevalence of chronic lung allograft dysfunction. However, survival was better in continuous positive airway pressure (CPAP) compliant SDB patients compared to SDB patients without CPAP treatment. These findings may be pertinent for systematic screening of SDB after LTX.

Myocardial Infarction after Kidney Transplantation: A Risk and Specific Profile Analysis from a Nationwide French Medical Information Database

INTRODUCTION

Renal transplant recipients have a high peri-operative risk for cardiovascular events. The post-transplantation period also carries a risk of myocardial infarction (MI). Coronary artery disease (CAD) is a leading cause of death in these patients. We aimed to assess the risk of MI, the specific morbidity profile of MI after transplantation as well as the long-term prognosis after MI in renal transplantation (RT) patients regarding cardiovascular (CV) death and all-cause death.

METHODS

From a French national medical information database, all of the patients seen in French hospitals in 2013 with at least 5-years follow-up were retrospectively identified and patients without transplantation but with previous dialysis at baseline were excluded. There were 17,526 patients with RT and 3,288,857 with no RT.

RESULTS

Among these patients, 1020 in the RT group (5.8%), and 93,320 in the non-RT group (2.8%) suffered acute MI during a median follow-up of 5.4 years. After multivariable adjustment, risk of MI was higher in RT patients than in non-RT patients (HR 1.45, IC 95% 1.35-1.55). The mean age was 59.5 years for transplant patients with MI, and 70.6 years for the reference population with MI (p < 0.0001). MI patients with RT (vs. non RT patients) were more likely to have hypertension, diabetes dyslipidemia, and peripheral artery disease (76.0% vs. 48.1%, 38.7% vs. 25.2%, 33.2% vs. 23.2%, and 31.2% vs. 17.3%, respectively, p < 0.0001). Incidence of non ST-elevation MI (NSTEMI) was higher in RT patients while incidence of ST-elevation MI (STEMI) was higher in patients without RT. In unadjusted analysis, risk of all-cause death and CV death within the first month after MI were higher in patients without RT (18% vs. 11.1% p < 0.0001 and 12.3% vs. 7.8%, p < 0.0001, respectively). However, multivariable analysis indicated that risk of all-cause death was higher in patients with RT than in those with no RT (adjusted HR 1.15 IC 95% 1.03-1.28).

CONCLUSIONS

MI is not an uncommon complication after RT (incidence of around 5.8% after 5 years). RT is independently associated with a 45% higher risk of MI than in patients without RT, with a predominance of NSTEMI. MI in patients with RT is independently associated with a 15% higher risk of all-cause death than that in patients with MI and no RT.

Prevalence and Risk Factors of New-Onset Diabetes After Transplantation (NODAT)

Background

New-onset diabetes after transplantation (NODAT) is a serious complication after a solid organ transplant. NODAT occurs in 2% to 53% of all solid organ transplant recipients. The identification of high-risk patients and the implementation of measures to limit the development of NODAT can improve the long-term patient prognosis.

Material/Methods

Our study group consisted of 336 patients undergoing heart transplant. Patients with prior diabetes (60 patients) were excluded from analysis. The remaining 276 patients were divided in 2 groups: with NODAT (n=109) and without NODAT (n=167). Logistic regression analysis was used for NODAT risk factor assessment.

Results

NODAT occurred in 109 (32%) out of 336 patients without diagnosed diabetes before heart transplantation. Risk factors for post-transplant diabetes mellitus, which was shown by the analysis of the collected data, were BMI at discharge (OR=1.082, CI 1.011–1.158, p=0.0233), history of diagnosed CMV infection (OR=1.464, CI 1.068–2.007, p=0.0179), and age over 51 years (OR=1.634, CI 1.274–2.095, p=0.0001).

Conclusions

1. New-onset diabetes after transplantation (NODAT) or long-lasting hypoglycemia (over 2 years after transplantation) was diagnosed in 32% patients after heart transplantation developed. 2. The risk factors of NODAT were BMI at discharge and history of diagnosed CMV infection, and age over 51 years was an independent risk factor.

Statin Use Is Prospectively Associated With New-Onset Diabetes After Transplantation in Renal Transplant Recipients

OBJECTIVE

New-onset diabetes after transplantation (NODAT) is frequent and worsens graft and patient outcomes in renal transplant recipients (RTRs). In the general population, statins are diabetogenic. This study investigated whether statins also increase NODAT risk in RTRs.

RESEARCH DESIGN AND METHODS

From a prospective longitudinal study of 606 RTRs (functioning allograft >1 year, single academic center, follow-up: median 9.6 [range, 6.6-10.2] years), 95 patients using statins were age- and sex-matched to RTRs not on statins (all diabetes-free at inclusion).

RESULTS

NODAT incidence was 7.2% (73.3% of these on statins). In Kaplan-Meier (log-rank test, P = 0.017) and Cox regression analyses (HR 3.86 [95% CI 1.21-12.27]; P = 0.022), statins were prospectively associated with incident NODAT, even independent of several relevant confounders including immunosuppressive medication and biomarkers of glucose homeostasis.

CONCLUSIONS

This study demonstrates that statin use is prospectively associated with the development of NODAT in RTRs independent of other recognized risk factors.

Evaluation of Tacrolimus Trough Level in Patients Who Developed Post-transplant Diabetes Mellitus After Kidney Transplantation: A Retrospective Single-Center Study in Saudi Arabia

BACKGROUND

Post-transplant diabetes mellitus (PTDM) is a complication after kidney transplantation. Studies showed an association between high trough levels of tacrolimus FK506 and PTDM. This study aims to investigate the association between FK506 trough levels during the first year after kidney transplant and the incidence of PTDM.

METHODS

This retrospective study included adult kidney transplant patients who were not diabetic before transplantation from 2011 to 2014. The analysis evaluated FK506 trough levels at different time points post-transplant, as well as other variables to determine whether they were associated with PTDM.

RESULTS

The cumulative incidence of PTDM was 22.5% with a median time to PTDM diagnosis of 10 months. PTDM patients had higher first FK506 (ng/mL) levels (P = .001), and more patients in the PTDM group had FK506 level >10 ng/mL during the first 3 months (P = .004). After 12 months of transplant, PTDM patients had higher body mass index (BMI) 28.3 ± 6.9 kg/m² compared to non-PTDM patients 26.4 ± 6.7 kg/m² (P = .015). Binary logistic regression analysis showed that age ≥40 years (odds ratio [OR] = 2.75, P = .004), BMI ≥25 kg/m² (OR = 2.04, P = .040), and FK506 level ≥10 ng/mL during the first 3 months (OR = 2.65, P = .009) were significantly related to PTDM development.

CONCLUSION

Patients with FK506 trough level >10 ng/mL during the first 3 months after transplantation are at higher risk of PTDM, especially in patients >40 years of age and/or who are overweight. These results may strengthen the notion that there is a connection between high FK506 trough levels and PTDM development.

Synergistic impact of pre-diabetes and immunosuppressants on the risk of diabetes mellitus during treatment of glomerulonephritis and renal vasculitis

Background

Glomerulonephritis is often treated with kidney-saving, but potentially diabetogenic immunosup­pressants such as glucocorticosteroids and calcineurin inhibitors. Unfortunately, there are little data on dysglycemia before and after diagnosis and during treatment of glomerulonephritis. We aimed to evaluate the occurrence and risk factors for pre-diabetes and incident diabetes among non-diabetic patients with glomerular disease with or without treatment with immunosuppressants.

Methods

A single-center, retrospective cohort study was performed on 229 non-diabetic immunosuppressant-naïve adults diagnosed with glomerulonephritis and renal vasculitis. Patients with known diabetes and prior immunosuppressant treatment were excluded. Outcomes of new-onset pre-diabetes and new-onset diabetes were defined according to American Diabetic Association criteria.

Results

Pre-diabetes was present pre-biopsy in 74 of the 229 patients (32.3%). During the median follow-up of 34.0 (23.3-47.5) months, 29 patients (12.7%) developed new-onset diabetes and 58 (25.3%) had new-onset pre-diabetes. Immunosuppressive therapy in patients with pre-existing pre-diabetes was associated with increased odds of new-onset diabetes compared to those without either risk factor (26.0% versus 5.0%; odds ratio, 6.67; 95% confidence interval [CI], 1.41 to 31.64), P = 0.02).

Conclusion

New-onset diabetes after immunosuppressant treatment occurred in one-quarter of patients with glomerulonephritis and pre-existing pre-diabetes. Physicians should screen for pre-diabetes when planning treatment with immunosuppressants, as its presence significantly increases the risk of diabetes mellitus.

Genetic Variants Associated With Immunosuppressant Pharmacokinetics and Adverse Effects in the DeKAF Genomics Genome-wide Association Studies

BACKGROUND

The immunosuppressants tacrolimus and mycophenolate are important components to the success of organ transplantation, but are also associated with adverse effects, such as nephrotoxicity, anemia, leukopenia, and new-onset diabetes after transplantation. In this report, we attempted to identify genetic variants which are associated with these adverse outcomes.

METHODS

We performed a genome-wide association study, using a genotyping array tailored specifically for transplantation outcomes containing 722 147 single nucleotide polymorphisms, and 2 cohorts of kidney allograft recipients-a discovery cohort and a confirmation cohort-to identify and then confirm genetic variants associated with immunosuppressant pharmacokinetics and adverse outcomes.

RESULTS

Several genetic variants were found to be associated with tacrolimus trough concentrations. We did not confirm variants associated with the other phenotypes tested although several suggestive variants were identified.

CONCLUSIONS

These results show that adverse effects associated with tacrolimus and mycophenolate are complex, and recipient risk is not determined by a few genetic variants with large effects with but most likely are due to many variants, each with small effect sizes, and clinical factors.

Determinants of Poor Glycemic Control in Patients with Kidney Transplants: A Single-Center Retrospective Cohort Study in Canada

Background:

Kidney transplant immunosuppressive medications are known to impair glucose metabolism, causing worsened glycemic control in patients with pre-transplant diabetes mellitus (PrTDM) and new onset of diabetes after transplant (NODAT).

Objectives:

To determine the incidence, risk factors, and outcomes of both PrTDM and NODAT patients.

Design:

This is a single-center retrospective observational cohort study.

Setting:

The Ottawa Hospital, Ontario, Canada.

Participant:

A total of 132 adult (>18 years) kidney transplant patients from 2013 to 2015 were retrospectively followed 3 years post-transplant.

Measurements:

Patient characteristics, transplant information, pre- and post-transplant HbA1C and random glucose, follow-up appointments, complications, and readmissions.

Methods:

We looked at the prevalence of poor glycemic control (HbA1c >8.5%) in the PrTDM group before and after transplant and compared the prevalence, follow-up appointments, and rate of complications and readmission rates in both the PrTDM and NODAT groups. We determined the risk factors of developing poor glycemic control in PrTDM patients and NODAT. Student t-test was used to compare means, chi-squared test was used to compare percentages, and univariate analysis to determine risk factors was performed by logistical regression.

Results:

A total of 42 patients (31.8%) had PrTDM and 12 patients (13.3%) developed NODAT. Poor glycemic control (HbA1c >8.5%) was more prevalent in the PrTDM (76.4%) patients compared to those with NODAT (16.7%; P < .01). PrTDM patients were more likely to receive follow-up with an endocrinologist (P < .01) and diabetes nurse (P < .01) compared to those with NODAT. There were no differences in the complication and readmission rates for PrTDM and NODAT patients. Receiving a transplant from a deceased donor was associated with having poor glycemic control, odds ratio (OR) = 3.34, confidence interval (CI = 1.08, 10.4), P = .04. Both patient age, OR = 1.07, CI (1.02, 1.3), P < .01, and peritoneal dialysis prior to transplant, OR = 4.57, CI (1.28, 16.3), P = .02, were associated with NODAT.

Limitations:

Our study was limited by our small sample size. We also could not account for any diabetes screening performed outside of our center or follow-up appointments with family physicians or community endocrinologists.

Conclusion:

Poor glycemic control is common in the kidney transplant population. Glycemic targets for patients with PrTDM are not being met in our center and our study highlights the gap in the literature focusing on the prevalence and outcomes of poor glycemic control in these patients. Closer follow-up and attention may be needed for those who are at risk for worse glycemic control, which include older patients, those who received a deceased donor kidney, and/or prior peritoneal dialysis.

Prediabetes and older age increase the risk of post-transplantation diabetes mellitus: Qatar experience

Post-transplantation diabetes mellitus (PTDM) is a major complication in kidney transplant recipients leading to reduced allograft and patient survival. Given the high prevalence of diabetes in Qatar, which is twice the global average, we were interested in determining the incidence of PTDM, identifying risk factors, and comparing clinical outcomes in kidney transplant recipients with and without diabetes. We retrospectively followed up 191 adult kidney allograft recipients transplanted between January 1, 2012, and December 31, 2016, for a median of 41 months. A total of 76 patients (40%) had pre-existing diabetes. A total of 39 patients developed PTDM during follow-up; they represent 34% of patients who did not have diabetes prior to transplantation. Two thirds of PTDM occurred within 3-6 months post-transplantation. Prediabetes before transplant [OR = 6.07 (1.24-29.74), P = .026] older recipient's age at the time of transplantation [OR = 1.10 (1.00-1.20), P = .039] and average fasting blood sugar during 3-6 months post-transplant [OR = 1.06 (1.01-1.11), P = .010] were independently associated with PTDM. Patient and kidney allograft survival rates exceeded 97% in all groups. The incidence of PTDM in kidney transplant recipients living in Qatar is high. Older age and prediabetes are independent risk factors for developing PTDM.

Perioperative Glycemic Control in Patients who Underwent Cardiac Transplantation and Effect on the Outcome at Discharge in a Tertiary Care Centre

OBJECTIVES

To study the glycemic status and insulin requirements in patients who underwent cardiac transplantation and to compare it among patients with and without diabetes mellitus. To compare preoperative glycemic status and perioperative insulin requirements with the outcome.

METHODS AND MATERIALS

The retrospective data of the glycemic status of patients before and after cardiac transplantation were collected and analyzed. Different variables like HbA1c, creatinine, age, BMI, and glycemic status were compared with the outcome.

RESULTS

A total of 18 patients with a mean age of 46.72 ± 16.94 years (mean ± SD) and a median age of 48.5 years underwent cardiac transplantation. The mean preoperative glycosylated hemoglobin (HbA1c) was 8.75 ± 2.15% (72 ± 2.36 mmol/mol) and 5.82 ± 0.45% (40 ± 4.89 mmol/mol) in patients with and without diabetes mellitus, respectively. The mean insulin requirement of insulin on postoperative days 0, 1, 2, and 3 was 1.396, 0.503, 0.490, and 0.537 (IU/kg/day) in patients with diabetes, whereas in patients without diabetes mellitus it was 1.955, 0.561, 1.19, and 0.61 (IU/kg/day), respectively. The mean insulin requirement at the time of discharge was 0.698 ± 0.43 IU/kg/day (mean ± SD) and 1.285 ± 1 IU/kg/day (mean ± SD) (p = 0.36) in patients with and without diabetes mellitus, respectively (p = 0.53, 0.11, 0.41, and 0.32, respectively). There was no association with the outcome when analyzed with different variables like HbA1c, creatinine, BMI, age, hemoglobin, insulin requirements, and glycemic status.

CONCLUSIONS

Perioperative glycemic control is crucial for successful cardiac transplantation irrespective of diabetic status.

Effects of Different Immunosuppressive Drugs on Incretins in Renal Transplant Patients

BACKGROUND

Immunosuppressive drugs used in transplantation patients, may contribute to the development of post-transplant diabetes mellitus through their possible adverse effects on incretins. We aimed to compare the effects of different immunosuppressive drugs used in renal transplantation patients on glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) levels.

PATIENTS AND METHODS

Forty five subjects were enrolled in the study (cyclosporine-treated 15 and tacrolimus-treated renal transplant patients 15, and healthy volunteers as a control group 15). Oral glucose tolerance test with 75 gr glucose was performed. GLP-1 and GIP levels were measured at 0 (baseline), 30, 60, 90, 120 min using ELISA method.

RESULTS

A statistically significant level of difference was detected in GLP-1 levels at the baseline, 30th and 120th minutes among all three groups (p < 0,001, p = 0,026 and p = 0,022, respectively). Baseline GLP-1 levels in cyclosporine-treated renal transplant patients were higher than in both tacrolimus-treated renal transplant patients (p = 0,016) and control groups (p < 0,001). GLP-1 levels at the 30th minute were higher in tacrolimus-treated renal transplant patients when compared to the cyclosporine-treated renal transplant patients (p = 0,024). GLP-1 levels at the 120th minute were higher in tacrolimus-treated renal transplant patients than the control group (p = 0,024). The areas under the curve of GLP-1 was higher in tacrolimus-treated renal transplant patients when compared to the control group (p = 0,018). GIP levels at 120th was lower in cyclosporine-treated renal transplant patients when compared to control group (p = 0,003).

CONCLUSION

These findings showed a temporally affected incretin hormones in renal transplant patients, a preserved GLP-1 response to an oral glucose load in renal transplant patients on cyclosporine and increased GLP -1 response to an oral glucose load in those on tacrolimus.

The tacrolimus-induced glucose homeostasis imbalance in terms of the liver: From bench to bedside

Tacrolimus (TAC), the mainstay of maintenance immunosuppressive agents, plays a crucial role in new-onset diabetes after transplant (NODAT). Previous studies investigating the diabetogenic effects of TAC have focused on the β cells of islets. In this study, we found that TAC contributed to NODAT through directly affecting hepatic metabolic homeostasis. In mice, TAC-induced hypoglycemia rather than hyperglycemia during starvation via suppressing gluconeogenetic genes, suggesting the limitation of fasting blood glucose in the diagnosis of NODAT. In addition, TAC caused hepatic insulin resistance and triglyceride accumulation through insulin receptor substrate (IRS)2/AKT and sterol regulatory element binding protein (SREBP1) signaling, respectively. Furthermore, we found a pivotal role of CREB-regulated transcription coactivator 2 (CRTC2) in TAC-induced metabolic disorders. The restoration of hepatic CRTC2 alleviated the metabolic disorders through its downstream molecules (eg, PCK1, IRS2, and SREBP1). Consistent with the findings from bench, low CRTC2 expression in graft hepatocytes was an independent risk factor for NODAT (odds ratio = 2.692, P = .023, n = 135). Integrating grafts' CRTC2 score into the clinical model could significantly increase the predictive capacity (areas under the receiver operating characteristic curve: 0.71 vs 0.79, P = .048). Taken together, in addition to its impact on pancreatic cells, TAC induces "hematogenous diabetes" via CRTC2 signaling. Liver-targeted management may be of help to prevent or heal TAC-associated diabetes.

High Plasma Branched-Chain Amino Acids Are Associated with Higher Risk of Post-Transplant Diabetes Mellitus in Renal Transplant Recipients

Post-transplant diabetes mellitus (PTDM) is a serious complication in renal transplant recipients. Branched-chain amino acids (BCAAs) are involved in the pathogenesis of insulin resistance. We determined the association of plasma BCAAs with PTDM and included adult renal transplant recipients (≥18 y) with a functioning graft for ≥1 year in this cross-sectional cohort study with prospective follow-up. Plasma BCAAs were measured in 518 subjects using nuclear magnetic resonance spectroscopy. We excluded subjects with a history of diabetes, leaving 368 non-diabetic renal transplant recipients eligible for analyses. Cox proportional hazards analyses were used to assess the association of BCAAs with the development of PTDM. Mean age was 51.1 ± 13.6 y (53.6% men) and plasma BCAA was 377.6 ± 82.5 µM. During median follow-up of 5.3 (IQR, 4.2–6.0) y, 38 (9.8%) patients developed PTDM. BCAAs were associated with a higher risk of developing PTDM (HR: 1.43, 95% CI 1.08–1.89) per SD change (p = 0.01), independent of age and sex. Adjustment for other potential confounders did not significantly change this association, although adjustment for HbA1c eliminated it. The association was mediated to a considerable extent (53%) by HbA1c. The association was also modified by HbA1c; BCAAs were only associated with renal transplant recipients without prediabetes (HbA1c < 5.7%). In conclusion, high concentrations of plasma BCAAs are associated with developing PTDM in renal transplant recipients. Alterations in BCAAs may represent an early predictive biomarker for PTDM.

Analysis of Risk Factors for Posttransplant Diabetes Mellitus After Kidney Transplantation: Single-Center Experience

OBJECTIVES

Posttransplant diabetes mellitus may severely affect the short-term and long-term outcomes of grafts and patient survival in kidney transplant recipients. The annual incidence rate of posttransplant diabetes mellitus ranges from 4% to 25%. In this study, our aim was to determine the possible risk factors in patients diagnosed with this disease.

MATERIALS AND METHODS

From November 1975 to May 2019, our transplant team performed 3012 kidney transplant procedures at different units within Baskent University Transplantation Centers. We retrospectively analyzed data of patients who were diagnosed with posttransplant diabetes mellitus between 2010 and 2019. The diagnosis was made according to the 2001 American Diabetes Association criteria (fasting plasma glucose level ≥ 126 mg/dL [7 mmol/L] in 2 measurements or random blood glucose level ≥ 200 mg/dL [11.1 mmol/L] within 12 months posttransplant).

RESULTS

For this study, 400 patients (292 male, 108 female) with end-stage renal disease and without diabetes met the initial inclusion criteria; 270 received hemodialysis, 26 received peritoneal dialysis, and 104 underwent preemptive kidney transplant. In this patient group, 62 patients (15.5%) developed post-transplant diabetes mellitus. When we compared patients who developed and did not develop posttransplant diabetes mellitus, cause of end-stage renal disease, dialysis type and duration, type of donor (living or deceased), and graft survival posttransplant were similar between groups. Baseline fasting plasma glucose level was significantly higher in patients who developed posttransplant diabetes mellitus (90 vs 85 mg/dL; P = .034). Patients who developed the disease were significantly older.

CONCLUSIONS

In our study, recipient age was the only risk factor for posttransplant diabetes mellitus. Older recipients should be examined more carefully for posttransplant diabetes mellitus, and less diabetogenic immunosuppressive drugs may be preferred.

Effect of Posttransplant Diabetes Mellitus on Graft Loss After Living-Donor Kidney Transplant at a Single Institution

BACKGROUND

This study aimed to evaluate predictive factors for graft loss in patients who received kidney transplantation (KT) from living kidney donors (LKDs) at a single institute in Japan.

METHODS

Our study focused on patients with end-stage renal disease who underwent KT from LKDs and were followed up for at least 1 year after surgery. The primary end point was graft survival (GS). GS after KT was analyzed using the Kaplan-Meier method. GS according to subgroup classification was analyzed using the log-rank test. A multivariate analysis was performed using a Cox proportional hazard model.

RESULTS

The median follow-up period was 105.5 months after KT. The 5- and 10-year GS rates were 97.8% and 96.0% in KT recipients (KTRs) without posttransplant diabetes mellitus (PTDM) and 89.9% and 63.2% in those with PTDM, respectively. The rate of graft loss was significantly higher in KTRs with PTDM than in those without PTDM (P < .001). Of the KTRs whose diabetes mellitus (DM) was cured after KT, those who underwent dialysis because of diabetic nephropathy had no graft loss. In the multivariate analysis, the serum creatinine level at 1 month after KT, PTDM, and human leukocyte antigen mismatches were significantly associated with graft loss after KT.

CONCLUSIONS

In this study, the rate of graft loss in KTRs with PTDM was significantly higher than that of KTRs without PTDM. However, among KTRs whose DM was cured after KT, those who underwent dialysis because of diabetic nephropathy had no graft loss.

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

BACKGROUND

Serum magnesium (Mg) status in kidney transplant recipients has been a center of attention in the past few years. Current evidence suggests an association between pre-transplant hypomagnesemia and post-transplant hyperglycemia.

OBJECTIVE

The purpose of this study was to assess the associations of pre-transplant magnesemia with blood glucose disturbances within 6 months post-kidney transplantation.

METHODS

In this retrospective cohort, 89 first-time kidney transplant recipients with 6 months of follow-up were included. None of the participants had a positive history of rejection, pre-transplant history of diabetes mellitus or fasting plasma glucose ≥ 100 mg/dL.

RESULTS

Post-transplant diabetes mellitus (PTDM) and impaired fasting glucose (IFG) 6 months post-transplant was found in 7.9% and 41.6% of the study group, respectively. The mean pre-transplant serum Mg level was 1.92 ± 0.30 mg/dL in the study population (n = 89), and it was significantly lower in IFG (n = 37) and IFG/PTDM (n = 44) groups compared to normoglycemic (n = 45) recipients (1.83 ± 0.31 mg/dL vs. 2.00 ± 0.27 mg/dL, P = 0.008, and 1.84 ± 0.31 mg/dL vs. 2.00 ± 0.27 mg/dL, P = 0.012, respectively). Patients with serum Mg less than 1.9 mg/dL were nearly 2.6 times more likely to develop IFG or IFG/PTDM within 6 months post-transplant (P = 0.044 and P = 0.040, respectively).

CONCLUSIONS

Pre-transplant hypomagnesemia may be considered a risk factor for developing post-transplant glycemic disturbances, and patients with lower pre-transplant Mg concentration could be at a higher risk for developing IFG.

Late Conversion From Calcineurin Inhibitors to Belatacept in Kidney-Transplant Recipients Has a Significant Beneficial Impact on Glycemic Parameters

Background.

Calcineurin inhibitors (CNIs) and steroids are strongly associated with new-onset diabetes after transplantation, worsening of pre-existing diabetes, and cardiovascular events. We assessed the benefit of conversion from CNI-based to belatacept-based immunosuppression in diabetic kidney-transplant (KT) recipients on glucose control and cardiovascular risk factors.

Methods.

In this retrospective, noncontrolled single-study conducted between May 2016 and October 26, 2018, we recruited KT recipients converted from CNIs to belatacept at least 6 months after KT. The primary endpoint was the evolution of hemoglobin A1c (HbA1c) between baseline and after 6 months of treatment. Secondary endpoints included modifications to antidiabetic drugs, other cardiovascular risk factors, and renal function.

Results.

One hundred and three KT recipients were included. Of these, 26 (25%) had type 2 diabetes. The patients were either receiving oral antidiabetic drugs (n = 21; 75%) or insulin therapy (n = 14; 54%). Overall HbA1c decreased significantly from 6.2 ± 1 to 5.8 ± 1%, P < 0.001. In diabetic patients, HbA1c decreased from 7.2 ± 1 to 6.5 ± 1%, P = 0.001. HbA1c significantly decreased in the subgroup of patients with new-onset diabetes after transplantation and whether diabetes was controlled at inclusion or not (ie, HA1c ≤7% or >7%). Moreover, no diabetic patient increased the number of oral antidiabetic drugs and the dose of basal insulin was not statistically different from baseline to 6 months (16 international unit at baseline and 16 international unit at 6 mo, P = 1). One patient had to start treatment by insulin pump. During follow-up, the renal function, body mass index, and hemoglobin level of all 103 patients remained stable, 2 patients presented acute cellular rejection, and no patient suffered from graft loss.

Conclusions.

A late switch from CNI to belatacept was a valuable therapeutic option for diabetic kidney recipients and substantially improved glycemic parameters.

OGTT 2-hour serum C-peptide index as a predictor of post-transplant diabetes mellitus in kidney transplant recipients

Background

The high incidence of post-transplant diabetes mellitus (PTDM) necessitates the identification of new factors to explain its pathogenesis. This study aimed to clarify the association between the C-peptide index (CPI) and PTDM.

Methods

A total of 290 non-diabetic kidney transplant patients were analyzed. All subjects underwent a 75 g oral glucose tolerance test (OGTT). Plasma glucose concentrations, serum C-peptide levels, hemoglobin A1c (HbA1c), and other biochemical indicators were measured. CPI was calculated as the ratio of serum C-peptide to plasma glucose.

Results

Among the 290 patients, 36 (12.4%) developed PTDM at the end of 1 year. Patients with PTDM had older age (P<0.001), higher levels of body mass index (BMI) (P=0.004) and HbA1c (P=0.001), a higher proportion of deceased donors (P=0.045), and lower levels of 2 h-CPI (P=0.02) than those without PTDM. The OGTT 2 h-CPI was positively correlated with BMI, HbA1c, type of calcineurin inhibitor, albumin, and triglyceride. Multivariate logistic regression and Cox hazard model analysis showed that pre-transplant OGTT 2 h-CPI was an independent predictor for the development of PTDM, together with age, BMI, and HbA1c.

Conclusions

Of the pre-transplant factors studied, OGTT 2 h-CPI proved to be an independent predictor of PTDM.