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

A Triple-Blind Randomized Controlled Trial on Impacts of Pioglitazone on Oxidative Stress Markers in Diabetic Kidney Transplant Recipients

Background: Oxidative stress as a major mediator of adverse outcomes in kidney transplant recipients who are prone to oxidative stress-mediated injury by pre-transplant and post-transplant conditions. Objectives: The purpose of this study was to assess the effects of Pioglitazone on oxidative stress biomarkers and blood glucose control in diabetic patients receiving insulin after kidney transplantation. Methods: In a triple-blind randomized placebo-controlled trial, sixty-two kidney transplanted diabetic patients (40 men and 24 women) were followed for 4 months after randomly assigned to the placebo group and Pioglitazone group (30 mg/d). All of the patients continued their insulin therapy irrespective of the group that they were assigned to evaluate the effects of the addition of pioglitazone on blood glucose and oxidative stress biomarkers, Malondialdehyde (MDA) and total protein carbonyls (TPC) serum levels. Results: At baseline, there were no statistically significant differences in glycemic control levels and oxidative markers between the two groups. After 4 months of intervention, a significant improvement occurred in Hemoglobin A1c (HBA1c) in the Pioglitazone group. The changes of HBA1c during 4 months of follow up in the Pioglitazone group show improvement in glucose control were as HBA1c in the placebo group increased by 0.3% (P = 0.0001). Moreover, at the end of the study, the MDA level was significantly lower in the Pioglitazone group (P < 0.0001, 1.22 - 3.90). Regarding the serum level of TPC, the changes were not statistically different at baseline and also at the end of the study between two groups. Conclusions: Administration of Pioglitazone in addition to insulin in diabetic kidney transplant patients not only improved glycemic control (evidenced by HBA1c) but also significantly decreased oxidative stress markers such as MDA.

Post-transplant diabetes mellitus and preexisting liver disease - a bidirectional relationship affecting treatment and management

Liver cirrhosis and diabetes mellitus (DM) are both common conditions with significant socioeconomic burden and impact on morbidity and mortality. A bidirectional relationship exists between DM and liver cirrhosis regarding both etiology and disease-related complications. Type 2 DM (T2DM) is a well-recognized risk factor for chronic liver disease and vice-versa, DM may develop as a complication of cirrhosis, irrespective of its etiology. Liver transplantation (LT) represents an important treatment option for patients with end-stage liver disease due to non-alcoholic fatty liver disease (NAFLD), which represents a hepatic manifestation of metabolic syndrome and a common complication of T2DM. The metabolic risk factors including immunosuppressive drugs, can contribute to persistent or de novo development of DM and NAFLD after LT. T2DM, obesity, cardiovascular morbidities and renal impairment, frequently associated with metabolic syndrome and NAFLD, may have negative impact on short and long-term outcomes following LT. The treatment of DM in the context of chronic liver disease and post-transplant is challenging, but new emerging therapies such as glucagon-like peptide-1 receptor agonists (GLP-1RAs) and sodium-glucose cotransporter 2 inhibitors (SGLT2i) targeting multiple mechanisms in the shared pathophysiology of disorders such as oxidative stress and chronic inflammation are a promising tool in future patient management.

Management of metabolic syndrome and cardiovascular risk after liver transplantation

Cardiovascular events are the second most prevalent cause of non-hepatic mortality in liver transplant recipients. The incidence of these events is projected to rise because of the growing prevalence of non-alcoholic steatohepatitis as a transplant indication and the ageing population of liver transplant recipients. Recipients with metabolic syndrome are up to four times more likely to have a cardiovascular event than recipients without, therefore prevention and optimal treatment of the components of metabolic syndrome are key in reducing the risk of these events. Although data on the treatment of metabolic comorbidities specifically in liver transplant recipients are scarce, there is detailed guidance from learned societies that mostly mirrors the guidance for patients at increased cardiovascular risk in the general population. In this Review, we discuss the management of the components of metabolic syndrome following liver transplantation and provide practical stepwise guidance. We also emphasise the need for adequately powered studies for the treatment of metabolic comorbidities in liver transplant recipients.

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.

Metabolic Disorders with Kidney Transplant

Metabolic disorders are highly prevalent in kidney transplant candidates and recipients and can adversely affect post-transplant graft outcomes. Management of diabetes, hyperparathyroidism, and obesity presents distinct opportunities to optimize patients both before and after transplant as well as the ability to track objective data over time to assess a patient's ability to partner effectively with the health care team and adhere to complex treatment regimens. Optimization of these particular disorders can most dramatically decrease the risk of surgical and cardiovascular complications post-transplant. Approximately 60% of nondiabetic patients experience hyperglycemia in the immediate post-transplant phase. Multiple risk factors have been identified related to development of new onset diabetes after transplant, and it is estimated that upward of 7%-30% of patients will develop new onset diabetes within the first year post-transplant. There are a number of medications studied in the kidney transplant population for diabetes management, and recent data and the risks and benefits of each regimen should be optimized. Secondary hyperparathyroidism occurs in most patients with CKD and can persist after kidney transplant in up to 66% of patients, despite an initial decrease in parathyroid hormone levels. Parathyroidectomy and medical management are the options for treatment of secondary hyperparathyroidism, but there is no randomized, controlled trial providing clear recommendations for optimal management, and patient-specific factors should be considered. Obesity is the most common metabolic disorder affecting the transplant population in both the pre- and post-transplant phases of care. Not only does obesity have associations and interactions with comorbid illnesses, such as diabetes, dyslipidemia, and cardiovascular disease, all of which increase morbidity and mortality post-transplant, but it also is intimately inter-related with access to transplantation for patients with kidney failure. We review these metabolic disorders and their management, including data in patients with kidney transplants.

Post-Transplantation Diabetes Mellitus

Solid organ transplantation (SOT) is an established therapeutic option for chronic disease resulting from end-stage organ dysfunction. Long-term use of immunosuppression is associated with post-transplantation diabetes mellitus (PTDM), placing patients at increased risk of infections, cardiovascular disease and mortality. The incidence rates for PTDM have varied from 10 to 40% between different studies. Diagnostic criteria have evolved over the years, as a greater understating of PTDM has been reached. There are differences in pathophysiology and clinical course of type 2 diabetes and PTDM. Hence, managing this condition can be a challenge for a diabetes physician, as there are several factors to consider when tailoring therapy for post-transplant patients to achieve better glycaemic as well as long-term transplant outcomes. This article is a detailed review of PTDM, examining the pathogenesis, diagnostic criteria and management in light of the current evidence. The therapeutic options are discussed in the context of their safety and potential drug-drug interactions with immunosuppressive agents.

A Retrospective Study of Glucagon-Like Peptide 1 Receptor Agonists for the Management of Diabetes After Transplantation

INTRODUCTION

Management of post-transplant diabetes mellitus is challenging; there is a lack of prospective randomized controlled trials for safety and efficacy of antidiabetic medications in solid organ recipients. Glucagon-like peptide 1 receptor agonists (GLP-1RA) are a relatively new class of medications used to manage type 2 diabetes in the general population. They have several benefits besides glycemic control, including weight loss and improved cardiovascular risk. However, they have not been studied extensively in the post-transplant population for safety and efficacy.

METHODS

We conducted a retrospective study of patients who had received kidney, liver, or heart transplant, had diabetes either pre- or post-transplant, and were treated with GLP-1RA. We identified seven kidney, seven liver, and five heart transplant recipients who had received GLP-1RA. We assessed changes in immunosuppressant levels, rejection episodes, changes in hemoglobin A1c (HbA1c), weight, and body mass index (BMI) while on the GLP-1RA. We also looked at changes in insulin dose, other diabetes medications, heart rate, blood pressure, and renal function.

RESULTS

After a mean follow-up period of 12 months, there were no significant changes in tacrolimus (FK506) levels and renal function for the period of GLP-1RA use. At the end of 12 months, the mean drop in weight was 4.86 kg [95% CI - 7.79, - 1.93]. The BMI decreased by a mean of 1.63 kg/m² at the end of 12 months [95% CI - 2.53, - 0.73]. HbA1c decreased from baseline by 1.08% [95% CI - 1.65, - 0.51], 0.96% [95% CI - 1.68, - 0.25], and 0.75% [95% CI - 1.55, 0.05] at 3, 6, and 12 months, respectively.

CONCLUSIONS

Our data suggest that GLP-1RA do not affect tacrolimus levels or transplant outcomes in solid organ transplant (SOT) recipients in the short term. GLP-1RA also seem to be as effective in SOT recipients for glycemic control and weight loss as in the non-transplant population with diabetes.

Association of body mass index and fasting plasma glucose concentration with post-transplantation diabetes mellitus in Chinese heart transplant recipients

Objective

Post-transplantation diabetes mellitus (PTDM) is a frequent complication after heart transplantation. We investigated the specific predictors of PTDM in Chinese heart transplant recipients and the prognostic value of these predictors.

Methods

We retrospectively analyzed 122 adult patients who underwent heart transplantation. Comparisons were made between patients with PTDM (n = 44) and those without PTDM (n = 78).

Results

During the median follow-up of 44 months, the cumulative incidence of PTDM was 19.7% at 1 year after transplantation and 36.1% at the endpoint. PTDM was associated with a significantly higher preoperative body mass index (BMI) (odds ratio [OR] = 1.349), fasting plasma glucose (FPG) concentration (OR = 2.538), and serum uric acid concentration (OR = 1.005) after transplantation. The area under the receiver operating characteristic curve was 0.708 and 0.763 for the BMI and FPG concentration, respectively. The incidence of acute rejection and infection were higher and the all-cause mortality rate was considerably greater in patients with than without PTDM.

Conclusions

A higher preoperative BMI (>23 kg/m²), FPG concentration (>5.2 mmol/L), and uric acid concentration could potentially predict PTDM in Chinese heart transplant recipients. PTDM influences long-term survival after heart transplantation.

Cardiovascular disease in the kidney transplant recipient: epidemiology, diagnosis and management strategies

Kidney transplantation (KT) is the optimal therapy for end-stage kidney disease (ESKD), resulting in significant improvement in survival as well as quality of life when compared with maintenance dialysis. The burden of cardiovascular disease (CVD) in ESKD is reduced after KT; however, it still remains the leading cause of premature patient and allograft loss, as well as a source of significant morbidity and healthcare costs. All major phenotypes of CVD including coronary artery disease, heart failure, valvular heart disease, arrhythmias and pulmonary hypertension are represented in the KT recipient population. Pre-existing risk factors for CVD in the KT recipient are amplified by superimposed cardio-metabolic derangements after transplantation such as the metabolic effects of immunosuppressive regimens, obesity, posttransplant diabetes, hypertension, dyslipidemia and allograft dysfunction. This review summarizes the major risk factors for CVD in KT recipients and describes the individual phenotypes of overt CVD in this population. It highlights gaps in the existing literature to emphasize the need for future studies in those areas and optimize cardiovascular outcomes after KT. Finally, it outlines the need for a joint 'cardio-nephrology' clinical care model to ensure continuity, multidisciplinary collaboration and implementation of best clinical practices toward reducing CVD after KT.

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.

Tacrolimus- and sirolimus-induced human β cell dysfunction is reversible and preventable

Posttransplantation diabetes mellitus (PTDM) is a common and significant complication related to immunosuppressive agents required to prevent organ or cell transplant rejection. To elucidate the effects of 2 commonly used agents, the calcineurin inhibitor tacrolimus (TAC) and the mTOR inhibitor sirolimus (SIR), on islet function and test whether these effects could be reversed or prevented, we investigated human islets transplanted into immunodeficient mice treated with TAC or SIR at clinically relevant levels. Both TAC and SIR impaired insulin secretion in fasted and/or stimulated conditions. Treatment with TAC or SIR increased amyloid deposition and islet macrophages, disrupted insulin granule formation, and induced broad transcriptional dysregulation related to peptide processing, ion/calcium flux, and the extracellular matrix; however, it did not affect regulation of β cell mass. Interestingly, these β cell abnormalities reversed after withdrawal of drug treatment. Furthermore, cotreatment with a GLP-1 receptor agonist completely prevented TAC-induced β cell dysfunction and partially prevented SIR-induced β cell dysfunction. These results highlight the importance of both calcineurin and mTOR signaling in normal human β cell function in vivo and suggest that modulation of these pathways may prevent or ameliorate PTDM.

The Use of GLP1R Agonists for the Treatment of Type 2 Diabetes in Kidney Transplant Recipients

Glucagon-like peptide-1 receptor agonists (GLP1RA) have been shown to improve glucose control and diabetes-related comorbidities in patients without solid organ transplants. The effectiveness, safety, and tolerability of GLP1RA after kidney transplantation have not been adequately studied.

Temporal trends of incident diabetes mellitus and subsequent outcomes in patients receiving kidney transplantation: a national cohort study in Taiwan

BACKGROUND

Allograft kidney transplantation has become a treatment of choice for patients with end-stage renal disease (ESRD), and post-transplant diabetes mellitus (PTDM) has been associated with impaired patient and graft survival. Taiwan has the highest incidence and prevalence rates of ESRD with many recipients and candidates of kidney transplantation. However, information about the epidemiologic features of PTDM in Taiwan is incomplete. Therefore, we aimed to investigate the prevalence and incidence of PTDM with subsequent patient and graft outcomes.

METHODS

Using the Taiwan National Health Insurance Research Database (NHIRD), 3663 kidney recipients between 1997 and 2011 were enrolled. We calculated the cumulative incidences of diabetes mellitus (DM) after transplantation. Cox proportional hazards model with competing risk analysis was used to calculate the hazard ratio (HR) and 95% confidence intervals (CI) between three targeted groups (DM, PTDM, non-DM). The outcomes of primary interest were the occurrence of graft failure excluding death with functioning graft, all-cause mortality, death with functioning graft and major adverse cardiovascular events (MACE) including myocardial infarction (MI), cerebrovascular accident (CVA) and congestive heart failure (CHF). Subgroup analysis for graft failure excluding death with functioning graft, MACE and all-cause mortality was performed, and interaction between PTDM and recipient age was examined.

RESULTS

Of 3663 kidney transplant recipients, 531 (14%) had pre-existing DM and 631 (17%) developed PTDM. Compared with non-DM group, the PTDM and DM groups exhibited higher risk of graft failure excluding death with functioning graft (PTDM: HR 1.65, 95% CI 1.47-1.85; DM: HR 1.33, 95% CI 1.18-1.50), MACE (PTDM: HR 1.51, 95% CI 1.31-1.74; DM: HR 1.64, 95% CI 1.41-1.9), all-cause mortality (PTDM: HR 1.79, 95% CI 1.59-2.01; DM: HR 2.03, 95% CI 1.81-2.18), and death with functioning graft (PTDM: HR 1.94, 95% CI 1.71-2.20; DM: HR 1.94, 95% CI 1.71-2.21). Both PTDM and DM groups had increased cardiovascular disease-related mortality (PTDM: HR 2.14, 95% CI 1.43-3.20, p < 0.001; DM: HR 1.89, 95% CI 1.25-2.86, p = 0.002), cancer-related mortality (PTDM: HR 1.56, 95% CI 1.18-2.07, p = 0.002; DM: HR 1.89, 95% CI 1.25-2.86, p = 0.027), and infection-related mortality (PTDM: HR 1.47, 95% CI 1.14-1.90, p = 0.003; DM: HR 2.25, 95% CI 1.77-2.84, p < 0.001) compared with non-DM group. The subgroup analyses showed that the add-on risks of MACE and mortality from PTDM were mainly observed in patients who were younger and those without associated comorbidities including atrial fibrillation, cirrhosis, CHF, and MI. Age significantly modified the association between PTDM and MACE (p_interaction < 0.01) with higher risk in recipients with PTDM aged younger than 55 years (adjusted HR 1.64, 95% CI 1.40-1.92, p < 0.001). A trend (p_interaction = 0.06) of age-modifying effect on the association between PTDM and all-cause mortality was also noted with higher risk in recipients with PTDM aged younger than 55 years.

CONCLUSIONS

In the present population-based study, the incidence of PTDM peaked within the first year after kidney transplantation. PTDM negatively impacted graft and patient outcomes. The magnitude of cardiovascular and survival disadvantages from PTDM were more pronounced in recipients aged less than 55 years. Further trials to improve prediction of PTDM and to prevent PTDM are warranted.

2. Classification and Diagnosis of Diabetes: Standards of Medical Care in Diabetes-2020

The American Diabetes Association (ADA) "Standards of Medical Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee (https://doi.org/10.2337/dc20-SPPC), a multidisciplinary expert committee, are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations, please refer to the Standards of Care Introduction (https://doi.org/10.2337/dc20-SINT). Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.

Obesity affects graft function but not graft loss in kidney transplant recipients

OBJECTIVE

This study was performed to examine the suitability of transplantation in kidney transplant recipients (KTRs) with a high body mass index (BMI).

METHODS

In total, 370 consecutive KTRs stratified according to the World Health Organization BMI categories were retrospectively analysed. The estimated glomerular filtration rate (eGFR) was used to assess allograft function.

RESULTS

The mean BMI was 26.2 kg/m2. Among all patients, 148 (40.0%) were pre-obese, 47 (12.7%) were class I obese, 11 (3.0%) were class II obese, and 9 (2.4%) were class III obese. A linear trend for male sex and younger age was observed from the normal BMI group through the progressively higher groups. Overweight and obese KTRs had a significantly higher incidence of pre-transplant diabetes, but there was no difference in post-transplant new-onset hyperglycaemia. Obesity was not a significant risk factor for a lower eGFR at the 1-year follow-up, but it became significant at the 2- and 3-year follow-ups. Graft loss occurred in 28 patients, and 25 patients died during follow-up. No difference in all-cause allograft loss was found among the different BMI groups during follow-up.

CONCLUSION

Obesity affects the eGFR in the long term. Allograft survival was lower, but not significantly.

Instructions for kidney recipients and donors (In English for medical providers and in Arabic for patients and donors)

Medical providers are often asked by their kidney recipients and donors about what to do or to avoid. Common questions include medications, diet, isolation, return to work or school, pregnancy, fasting Ramadan, or hajj and Omrah. However, there is only scant information about these in English language and none in Arabic. Here, we present evidence-based education materials for medical providers (in English language) and for patients and donors (in Arabic language). These educational materials are prepared to be easy to print or adopt by patients, providers, and centers.

Incidence of new-onset diabetes mellitus and association with mortality in childhood solid organ transplant recipients: a population-based study

BACKGROUND

Precise estimates of the long-term risk of new-onset diabetes and its impact on mortality among transplanted children are not known.

METHODS

We conducted a cohort study comparing children undergoing solid organ (kidney, heart, liver, lung and multiple organ) transplant (n = 1020) between 1991 and 2014 with healthy non-transplanted children (n = 7 134 067) using Ontario health administrative data. Outcomes included incidence of diabetes among transplanted and non-transplanted children, the relative hazard of diabetes among solid organ transplant recipients, overall and at specific intervals posttransplant, and mortality among diabetic transplant recipients.

RESULTS

During 56 019 824 person-years of follow-up, the incidence rate of diabetes was 17.8 [95% confidence interval (CI) 15-21] and 2.5 (95% CI 2.5-2.5) per 1000 person-years among transplanted and non-transplanted children, respectively. The transplant cohort had a 9-fold [hazard ratio (HR) 8.9; 95% CI 7.5-10.5] higher hazard of diabetes compared with those not transplanted. Risk was highest within the first year after transplant (HR 20.7; 95% CI 15.9-27.1), and remained elevated even at 5 and 10 years of follow-up. Lung and multiple organ recipients had a 5-fold (HR 5.4; 95% CI 3.0-9.8) higher hazard of developing diabetes compared with kidney transplant recipients. Transplant recipients with diabetes had a three times higher hazard of death compared with those who did not develop diabetes (HR 3.3; 95% CI 2.3-4.8).

CONCLUSIONS

The elevated risk of diabetes in transplant recipients persists even after a decade, highlighting the importance of ongoing surveillance. Diabetes after transplantation increases the risk of mortality among childhood transplant recipients.

FXR activation alleviates tacrolimus-induced post-transplant diabetes mellitus by regulating renal gluconeogenesis and glucose uptake

BACKGROUND

Tacrolimus (FK506)-induced diabetes mellitus is one of the most important factors of post-transplant diabetes mellitus (PTDM). However, the detailed mechanisms underlying PTDM are still unclear. Farnesoid X receptor (FXR) regulates glycolipid metabolism. The objective of this study was to explore whether FXR is involved in the development of tacrolimus-induced diabetes mellitus.

METHODS

After C57BL/6J mice were treated with tacrolimus (FK506) for 3 months, the fasting blood glucose levels, body weights, renal morphological alterations, and mRNA expression levels of phosphoenolpyruvate carboxykinase (PEPCK) and glucose transporter 2 (GLUT2) among the control group, the FK506 group and the FK506 + GW4064 (a FXR agonist) group (n = 7) were measured. The intracellular location of peroxisome proliferator activated receptor γ coactivator-1α (PGC1α) and forkhead box O1 (FOXO1) was detected by immunofluorescence. Human renal cortex proximal tubule epithelial cells (HK-2) were treated with 15 μM FK506 or 4 μM FXR agonist (GW4064) for 24, 48 and 72 h, and the expression levels of FXR, gluconeogenesis and glucose uptake, representing the enzymes PEPCK and GLUT2, were detected with real-time PCR and western blot analyses. Finally, the mRNA levels of PEPCK and GLUT2 in HK-2 cells were measured after FXR was upregulated.

RESULTS

FK506 significantly inhibited the mRNA and protein levels of FXR at 48 h and 72 h in HK-2 cells (P < 0.05). Meanwhile, FK506 promoted gluconeogenesis and inhibited glucose uptake in HK-2 cells (P < 0.05). However, overexpression of FXR in transfected HK-2 cell lines significantly inhibited gluconeogenesis and promoted glucose uptake (P < 0.05). The FXR agonist GW4064 significantly decreased the fasting blood glucose in mice challenged with FK506 for 3 months (P < 0.05), inhibited gluconeogenesis (P < 0.05) and significantly promoted glucose uptake (P < 0.05). Immunofluorescence staining and western blot analyses further revealed that FXR activation may affect the translocation of PGC1α and FOXO1 from the nucleus to the cytoplasm.

CONCLUSIONS

FXR activation may mitigate tacrolimus-induced diabetes mellitus by regulating gluconeogenesis as well as glucose uptake of renal cortex proximal tubule epithelial cells in a PGC1α/FOXO1-dependent manner, which may be a potential therapeutic strategy for the prevention and treatment of PTDM.

A review of non-immune mediated kidney disease in systemic lupus erythematosus: A hypothetical model of putative risk factors

About half of patients with systemic lupus erythematosus (SLE) are diagnosed with lupus nephritis (LN). Patients with SLE are also at increased risk for diabetes, hypertension and obesity, which together account for >70% of end-stage renal disease in the general population. The frequencies of non-LN related causes of kidney disease, and their contribution to kidney disease development and progression among patients with SLE have been inadequately studied. We hypothesize that a substantial, and increasing proportion of kidney pathology in patients with SLE might not directly relate to LN but instead might be explained by non-immune mediated factors such as diabetes, hypertension, and obesity. The goal of the manuscript is to draw attention to hypertension, diabetes and obesity as potential alternative causes of kidney damage in patients with SLE. Further, we suggest that misclassification of kidney disease etiology in patients with SLE might have important ramifications for clinical trial recruitment, epidemiologic investigation, and clinical care. Future studies aiming to elucidate and distinguish discrete causes of kidney disease - both clinically and histologically - among patients with SLE are desperately needed as improved understanding of disease mechanisms is paramount to advancing therapeutic discovery. Collaboration among rheumatologists, pathologists, nephrologists, and endocrinologists, and the availability of dedicated research funding, will be critical to the success of such efforts.

Trends, Determinants, and Impact on Survival of Post-Lung Transplant Weight Changes: A Single-center Longitudinal Retrospective Study

BACKGROUND

Weight gain is commonly seen in lung transplant (LTx) recipients. Although previous studies have focused on weight changes at fixed time periods and relatively early after transplant, trends over time and long-term weight evolution have not been described in this population. The study objectives were to document weight changes up to 15 years post-LTx and assess the predictors of post-LTx weight changes and their associations with mortality.

METHODS

Retrospective cohort study of LTx recipients between January 1, 2000, and November 30, 2016 (n = 502). Absolute weight changes from transplant were calculated at fixed time periods (6 mo, 1, 2, 5, 10, and 15 y), and continuous trends over time were generated. Predictors of weight changes and their association with mortality were assessed using linear and Cox regression analysis.

RESULTS

LTx recipients experienced a gradual increase in weight, resulting from the combination of multiple weight trajectories. Interstitial lung disease diagnosis negatively predicted post-LTx weight changes at all time points, whereas transplant body mass index categories were significant predictors at earlier time points. Patients with a weight gain of >10% at 5 years had a better survival (hazard ratio [HR], 0.36; 95% confidence interval [CI], 0.20-0.66), whereas a 10% weight loss at earlier time points was associated with worse survival (1 y: HR, 2.04; 95% CI, 1.22-3.41 and 2 y: HR, 2.37; 95% CI, 1.22-4.58).

CONCLUSIONS

Post-LTx weight changes display various trajectories, are predicted to some extent by individual and LTx-related factors, and have a negative or positive impact on survival depending on the time post-LTx. These results may lead to a better individualization of weight management after transplant.

Utility of HbA1c assessment in people with diabetes awaiting liver transplantation

AIMS

To investigate the relationship between HbA_1c and glucose in people with co-existing liver disease and diabetes awaiting transplant, and in those with diabetes but no liver disease.

METHODS

HbA_1c and random plasma glucose data were collected for 125 people with diabetes without liver disease and for 29 people awaiting liver transplant with diabetes and cirrhosis. Cirrhosis was caused by non-alcoholic fatty liver disease, hepatitis C, alcoholic liver disease, hereditary haemochromatosis, polycystic liver/kidneys, cryptogenic/non-cirrhotic portal hypertension and α-1-antitrypsin-related disease.

RESULTS

The median (interquartile range) age of the diabetes with cirrhosis group was 55 (49-63) years compared to 60 (50-71) years (P=0.13) in the group without cirrhosis. In the diabetes with cirrhosis group there were 21 men (72%) compared with 86 men (69%) in the group with diabetes and no cirrhosis (P=0.82). Of the group with diabetes and cirrhosis, 27 people (93%) were of white European ethnicity, two (7%) were South Asian and none was of Afro-Caribbean/other ethnicity compared with 94 (75%), 16 (13%), 10 (8%)/5 (4%), respectively, in the group with diabetes and no cirrhosis (P=0.20). Median (interquartile range) HbA_1c was 41 (32-56) mmol/mol [5.9 (5.1-7.3)%] vs 61 (52-70) mmol/mol [7.7 (6.9-8.6)%] (P<0.001), respectively, in the diabetes with cirrhosis group vs the diabetes without cirrhosis group. The glucose concentrations were 8.4 (7.0-11.2) mmol/l vs 7.3 (5.2-11.5) mmol/l (P=0.17). HbA_1c was depressed by 20 mmol/mol (1.8%; P<0.001) in 28 participants with cirrhosis but elevated by 28 mmol/mol (2.6%) in the participant with α-1-antitrypsin disorder. Those with cirrhosis and depressed HbA_1c had fewer larger erythrocytes, and higher red cell distribution width and reticulocyte count. This was reflected in the positive association of glucose with mean cell volume (r=0.39) and haemoglobin level (r=0.49) and the negative association for HbA_1c (r=-0.28 and r=-0.26, respectively) in the diabetes group with cirrhosis.

CONCLUSION

HbA_1c is not an appropriate test for blood glucose in people with cirrhosis and diabetes awaiting transplant as it reflects altered erythrocyte presentation.

Effects of exercise training on cardiovascular risk factors in kidney transplant recipients: a systematic review and meta-analysis

BACKGROUND

Whether exercise can improve cardiovascular health in kidney transplant recipients (KTRs) is unclear. Therefore, we performed a systematic review of the effects of exercise on cardiovascular risk factors in this population setting.

METHODS

Randomized control trials (RCTs) evaluating the impact of exercise on major clinical outcomes in KTRs were identified by searches in Cochrane CENTRAL, PubMed, EMBASE, OVID and CBM updated to December 2018. The main outcomes of interest were blood pressure, lipid profile, blood glucose level, arterial stiffness, kidney function, body weight, body mass index, exercise tolerance (VO2 peak) and quality of life (QOL).

RESULTS

After screening 445 studies in the database, we included 12 RCTs in the review and 11 RCTs for further qualitative analysis. The results indicate a significant improvement in small arterial stiffness [mean difference (MD): -1.14, 95% confidence interval (CI): -2.19-0.08, p = .03], VO2 peak (MD: 2.25, 95% CI: 0.54-3.69, p = .01), and QOL (MD: 12.87, 95% CI: 6.80-18.94, p < .01) after exercise intervention in KTRs. However, there is no evidence for an improvement in blood pressure, lipid profile, blood glucose level, kidney function, body weight or body mass index.

CONCLUSION

Exercise intervention in KTRs improves arterial stiffness but does not consistently contribute to the modification of other CVD risk factors like hypertension, dyslipidemia, hyperglycemia, decreased kidney function and obesity. Exercise also improves exercise tolerance and QOL in KTRs.

Managing Endocrine Disorders in Adults After Hematopoietic Stem Cell Transplantation

Hematopoietic stem cell transplantation (HSCT) has become a potentially curative therapy for an increasing number of malignant and non-malignant conditions. As survival rates continue to improve, the focus of patient care has shifted from managing not only immediate but also long-term complications. Endocrine disorders are among the most prevalent late effects following HSCT. Detecting and treating such conditions offer new challenges, as well as opportunities to reduce preventable morbidity and mortality associated with HSCT. Our objective is to summarize recent literature and describe practical approaches to screening for and managing endocrine-related late effects. We focus on dyslipidemia, diabetes, thyroid disorders, osteoporosis, and hypogonadism. Mechanisms, monitoring, and management recommendations for each disorder are outlined. Growing data on these disorders in the post-transplant setting highlight the need for future study and evidence-based guidelines.

Immunosuppression following organ transplantation. Part 2: complications and their management

Advances in the care of patients who have had a solid organ transplant has led to a growing population of post-transplant patients, who are also living for longer. As a result of their longer life expectancy, transplant recipients often face a multitude of challenges, including optimising their immunosuppressive regimens and managing potential complications. Life-threatening infections, malignancies, and organ-specific toxicities are the complications post-transplant patients commonly encounter and these complications are often associated with increased morbidity and mortality, adverse graft functioning and survival, profound impairment in the patient's quality of life, and significant healthcare burden. This article, the second of two parts, gives an overview of the issues involved in the care of patients who are receiving immunosuppressants. The common complications encountered by post-transplant patients are discussed and their assessment, management, prevention and treatment explored.

Incidence of Post-transplantation Diabetes Mellitus Within 1 Year After Kidney Transplantation and Related Factors in Korean Cohort Study

BACKGROUND

Post-transplantation diabetes mellitus (PTDM) is associated with a higher risk of mortality and graft loss. The reported incidence of PTDM after kidney transplantation (KT) varies from 10% to 74% and varies by country and ethnicity. There are few reports of nationwide cohort studies on PTDM incidence and related factors in Korea. The purpose of this study was to evaluate incidence of PTDM and related factors within 1 year after KT in Korea.

METHODS

The KoreaN cohort study for Outcome in patients With Kidney Transplantation (KNOW-KT) enrolled 1080 recipients from July 2012 to August 2016. This study included 723 recipients, excluding 273 patients with pretransplant DM and 84 patients who were lost from follow-up within 1 year after KT.

RESULTS

Among 723 recipients, 85 (11.8%) recipients were diagnosed and treated with PTDM. Recipient age, HLA mismatches, hemoglobin A1c (HbA1c), waist-hip ratio (WHR), and use of prednisolone were significantly higher in PTDM group than the nondiabetic group. In the multivariable logistic regression analysis, independent risk factors for PTDM were older recipient age, higher WHR, and HbA1c before KT.

CONCLUSION

The incidence of PTDM was 11.8% in a nationwide Korean cohort study. The factors related to the development of PTDM within 1 year after KT were older recipient age and higher WHR, and HbA1c levels before KT. In recipients with high WHR, it is important to control pretransplant abdominal obesity to prevent PTDM after KT.

Impact of Conversion From Cyclosporine to Tacrolimus on Glucose Metabolism and Cardiovascular Risk Profiles in Long-Term Stable Kidney Transplant Recipients

BACKGROUND

Compared to tacrolimus, cyclosporine increases cardiovascular risk. Furthermore, tacrolimus has a negative effect on glucose metabolism compared to cyclosporine. This study investigated the effect of the conversion from cyclosporine to tacrolimus for immunosuppressive therapy on glucose metabolism and cardiovascular risk profiles in long-term stable kidney transplant recipients (KTRs).

METHODS

In this prospective, open-label, single-arm study, 36 KTRs were enrolled; 3 were excluded. Patients were evaluated for glucose metabolism and cardiovascular risk factors at baseline, 3, and 6 months after conversion of medication. Serial changes were analyzed by repeated analysis of variance.

RESULTS

The mean duration from transplantation was 12.6 ± 4.0 years and baseline serum creatinine levels were 1.10 ± .23 mg/dL. After conversion, fasting plasma glucose levels increased sequentially from 101.7 ± 18.5 to 107.4 ± 21.3 mg/dL (P = .007), and glycated hemoglobin levels increased from 5.7 ± .8 to 6.0 ± 1.2% (P = .016). Among cardiovascular risk factors, fibrinogen levels were decreased (P = .015), but other factors, including blood pressure and lipid profile, did not change (all P > .05). There was no change in renal function, including serum creatinine (P = .611) and urine protein-to-creatinine ratio (P = .092). Body mass index levels were decreased (P = .037) and body weight tended to decrease (P = .063).

CONCLUSIONS

Switching immunosuppressant therapy to tacrolimus has an apparent negative effect on glucose metabolism and imparts an unclear advantage on cardiovascular risk profiles for long-term stable KTRs.

Management of Diabetes Mellitus in Normal Renal Function, Renal Dysfunction and Renal Transplant Recipients, Focusing on Glucagon-Like Peptide-1 Agonist: A Review Based upon Current Evidence

Diabetes Mellitus (DM) is a leading cause of both Cardiovascular Disease (CVD) and End-stage Renal Disease (ESRD). After 2008, there has been much evidence presented, and recently the guidelines for sugar control have changed to focus on being more disease orientated. GLP-1 Receptor Agonists (GLP-1R) and sodium glucose cotransporter-2 inhibitors are suggested as the first line towards fighting all DM, CVD and ESRD. However, the benefits of GLP-1R in organ transplantation recipients remain very limited. No clinical trials have been designed for this particular population. GLP-1R, a gastrointestinal hormone of the incretin family, possesses antidiabetic, antihypertensive, anti-inflammatory, anti-apoptotic and immunomodulatory actions. There are few drug–drug interactions, with delayed gastric emptying being the major concern. The trough level of tacrolimus may not be significant but should still be closely monitored. There are some reasons which support GLP-1R in recipients seeking glycemic control. Post-transplant DM is due to an impaired β-cell function and glucose-induced glucagon suppression during hyperglycemia, which can be reversed by GLP-1R. GLP-1R infusion tends to relieve immunosuppressant related toxicity. Until now, in some cases, glycemic control and body weight reduction can be anticipated with GLP-1R. Additional renal benefits have also been reported. Side effects of hypoglycemia and gastrointestinal discomfort were rarely reported. In conclusion, GLP-1R could be implemented for recipients while closely monitoring their tacrolimus levels and any potential side effects. Any added benefits, in addition to sugar level control, still require more well-designed studies to prove their existence.

Comparison of Glucose Tolerance between Kidney Transplant Recipients and Healthy Controls

Post-transplant hyperglycemia and new-onset diabetes mellitus after transplantation (NODAT) are common and important metabolic complications. Decreased insulin secretion and increased insulin resistance are important to the pathophysiologic mechanism behind NODAT. However, the progression of glucose intolerance diagnosed late after kidney transplantation remains clearly unknown. Enrolled in this study were 94 kidney transplant recipients and 134 kidney transplant donors, as the healthy controls, who were treated at our institution. The 75 g-oral glucose tolerance test (OGTT) was performed in the recipients, and the healthy controls received an OGTT before donor nephrectomy. We assessed the prevalence of glucose intolerance including impaired fasting glucose and/or impaired glucose tolerance, as well as insulin secretion and insulin resistance using the homeostasis model assessment, and compared the results between the two groups. Multivariate analysis after adjustment for age, gender, body mass index, estimated glomerular filtration rate, and systolic blood pressure showed that the prevalence of glucose intolerance, insulin resistance, insulin secretion, and 2 h plasma glucose levels were significantly higher in the kidney transplant recipients compared to the healthy controls. Elevation of insulin secretion in kidney transplant recipients may be compensatory for increase of insulin resistance. Impaired compensatory pancreas β cell function may lead to glucose intolerance and NODAT in the future.

Obesity and bariatric intervention in patients with chronic renal disease

Obesity is associated with chronic metabolic conditions that directly and indirectly cause kidney parenchymal damage. A review of the literature was conducted to explore existing evidence of the relationship between obesity and chronic kidney disease as well as the role of bariatric surgery in improving access to kidney transplantation for patients with a high body mass index. The review showed no definitive evidence to support the use of a transplant eligibility cut-off parameter based solely on the body mass index. Moreover, in the pre-transplant scenario, the obesity paradox is associated with better patient survival among obese than non-obese patients, although promising results of bariatric surgery are emerging. However, until more information regarding improvement in outcomes for obese kidney transplant candidates is available, clinicians should focus on screening of the overall frailty condition of transplant candidates to ensure their eligibility and addition to the wait list.

Chronic kidney disease progression in kidney transplant recipients: A focus on traditional risk factors

Kidney transplant recipients are a subset of patients with chronic kidney disease (CKD) that remain at high risk for progression to dialysis and mortality. Recent advances in immunosuppression have only partially improved long-term graft and patient survival. Discovery of new immunosuppressive regimens is a slow and resource-intensive process. Hence, recognition and management of modifiable allogeneic and non-allogeneic risk factors for progression to CKD among kidney transplant recipients is of major interest for improving long-term outcomes. Graft survival is mainly determined by the quality of the allograft and by the patient's alloimmune response, which is influenced by human leukocyte antigen matching and the presence of donor-specific antibodies. Alloimmune responses manifest as acute and chronic forms of cell- and antibody-mediated rejection, which can be worsened by patient non-adherence or under-immunosuppression. However, donor and patient ages, glomerular disease recurrence, time on dialysis, pre-existing cardiovascular burden, medication side-effects and traditional risk factors, such as hypertension, proteinuria, anaemia, dyslipidaemia, diabetes and bone mineral disorder, which can ultimately lead to severe endothelial derangement, also contribute to graft loss and mortality. These traditional risk factors, common to pre-dialysis patients, often are considered of secondary importance when compared to alloimmunity and immunosuppression concerns. In this review article, we focus on the epidemiological, pathophysiological and therapeutic features of non-allogeneic traditional risk factors for CKD. We also discuss the benefit of adopting a multidisciplinary approach to pursue the same therapeutic targets recommended for pre-dialysis patients.

Serum Apolipoprotein B and A1 Concentrations Predict Late-Onset Posttransplant Diabetes Mellitus in Prevalent Adult Kidney Transplant Recipients

BACKGROUND

Glucose metabolism links closely to cholesterol metabolism. Posttransplant diabetes mellitus (PTDM) adversely affects posttransplant outcomes, but its risk factors in relation to cholesterol metabolism have not been fully delineated. The apolipoprotein B/A1 (Apo B/A1) ratio, which is associated with insulin resistance, has not been evaluated in kidney transplant recipients as a risk factor for PTDM.

OBJECTIVE

The objective of this study was to determine whether serum apolipoprotein profiles predict late PTDM, defined as a new onset diabetes occurring greater than 3 months posttransplant.

DESIGN

Retrospective chart review of a prevalent population of kidney transplant recipients.

SETTING

Large transplant center in Ontario, Canada.

PATIENTS

We identified 1104 previously nondiabetic adults who received a kidney transplant between January 1, 1998, and December 1, 2015, and were followed at 1 transplant center.

MEASUREMENTS

Recipients provided testing for serum apolipoprotein B (Apo B) and apolipoprotein A1 (Apo A1) concentrations from 2010, either at 3 months posttransplant for new transplant recipients or the next clinic visit for prevalent recipients. Late PTDM defined using Canadian Diabetes Association criteria as occurring ≥3 months posttransplant was recorded until May 1, 2016.

METHODS

All analyses were conducted with R, version 3.4.0 (The R Foundation for Statistical Computing). Comparisons were made using Student t test, Fisher exact test or chi-square test, Kaplan-Meier methodology with the logrank test, or Cox proportional hazards analysis as appropriate. Covariates for the multivariate Cox proportional hazards models of PTDM as the outcome variable were selected based on significance of the univariate associations and biological plausibility.

RESULTS

There were 53 incident late PTDM cases, or 1.71 cases per 100 patient-years. Incident late PTDM differed between the highest and lowest quartiles for Apo B/A1 ratio, 2.47 per 100 patient-years vs 0.88 per 100 patient-years (P = .005 for difference). In multiple Cox regression analysis, first measured serum Apo B/A1 concentration better predicted subsequent PTDM than low-density lipoprotein cholesterol (LDL-C; hazard ratio [HR] = 7.80 per unit increase, P = .039 vs HR = 1.05 per unit increase, P = .774). Non-high-density lipoprotein cholesterol (HDL-C) concentrations also did not predict PTDM (P = .136). By contrast to Apo B, Apo A1 was protective against PTDM in statin users (HR = 0.17 per unit increase, P = .016).

LIMITATIONS

Posttransplant diabetes mellitus cases occurring before apolipoprotein testing was implemented were not included in the analysis.

CONCLUSIONS

Apolipoproteins B and A1 better predict late PTDM than conventional markers of cholesterol metabolism.

Management of Recurrent and De Novo NAFLD/NASH After Liver Transplantation

Nonalcoholic steatohepatitis (NASH) is a growing indication for liver transplant whether the primary or secondary cause of liver disease, and it is expected to be the leading indication in the years to come. Nonalcoholic steatohepatitis recurs after transplant but the impact of the recurrence on allograft and patient outcomes is unclear. A group of multidisciplinary transplant practice providers convened at the International Liver Transplantation Society NASH consensus conference with the purpose of determining the current knowledge and future directions for understanding the recurrence rates, risk and management of NASH in the transplant allograft. Specific questions relating to posttransplant NASH were proposed and reviewed in detail with recommendations on future actions to fill the knowledge gaps.

Intensive monitoring for post-transplant diabetes mellitus and treatment with dipeptidyl peptidase-4 inhibitor therapy

AIM

Current monitoring practices fail to diagnose patients with post-transplant hyperglycaemia and tend to delay initiation of treatment, which potentially results in adverse graft and morbidity outcomes. This real-world study set out to assess the impact on insulin resistance indices of a new clinical pathway for diagnosis and treatment of hyperglycaemia following renal transplantation.

METHODS

A hundred and forty-seven adult renal transplant recipients, without pre-existing diabetes, from a single centre were included. Patients transplanted between January 2008 to September 2015 formed the historical cohort. Patients transplanted between October 2015 and February 2018 were subject to a new clinical pathway - if they had fasting blood sugar levels more than 7 mmol/L or random blood glucose levels more than 11.1 mmol/L, they had early introduction of oral therapy, using the DPP-4 inhibitor linagliptin.

RESULTS

In the historical cohort, 19.8% were diagnosed with PTDM, compared to 46.3% in the protocol cohort. Amongst patients with PTDM, there was a significant difference in HOMA-IR (p = 0.02) between the historical cohort (median HOMA-IR 3.33) and the protocol cohort (median HOMA-IR 2.21). There was a significant difference at each time point (0,1,2-h measurements) of blood glucose levels form oral glucose tolerance testing between patients with and without PTDM in the historical cohort (p < 0.001), but no difference between patients in the protocol cohort.

CONCLUSION

Detection of PTDM was higher with the new clinical pathway. Early treatment of hyperglycaemia resulted in better insulin resistance scores. Larger prospective controlled studies focussing on early detection and management of PTDM with linagliptin are warranted.

Cystic fibrosis-related diabetes: optimizing care with a multidisciplinary approach

Cystic fibrosis-related diabetes (CFRD) is a common complication of cystic fibrosis and can be present in over 50% of adults with the disease. CFRD is associated with poorer clinical outcomes, including accelerated pulmonary function decline and excess morbidity. The management of CFRD is complex and differs from that of type 1 and type 2 diabetes mellitus such that clinicians responsible for the care of people with CFRD must work closely with colleagues across a number of different specialities and disciplines. This review aims to discuss why a multi-disciplinary approach is important and how it can be harnessed to optimize the care of people with CFRD.

Role of sex in post-transplant diabetes mellitus development: Are men and women equal?

INTRODUCTION

Sex differences are defined as biology-linked differences between women and men that occur through the sex chromosomes and their effects on organ systems.

MATERIAL AND METHODS

The objective of this prospective study was to determine risk factors for post-transplant diabetes mellitus (PTDM) in men and women.

RESULTS

A total of 417 patients (271 men and 146 women) were included in the monitored group. Age at the time of kidney transplantation (KT) >60 years and hypovitaminosis D at the time of KT (<20 μg/l) were identified as independent risk factors for PTDM in both men and women. It was further confirmed as an independent risk factor for men a waist circumference at the time of KT >94 cm, C-peptide at the time of KT >5 ng/ml, HOMA-IR >2 and triacylglycerols at the time of KT >1.7 mmol/l. In case of women, the dominant factor was BMI at the time of KT >30 kg/m2 and menopause at the time of KT. A significant decrease in C-peptide was recorded in women with PTDM.

CONCLUSION

It was confirmed that there are gender differences with regard to the development of PTDM after KT. Women show pancreas β cell dysfunction, whereas insulin resistance and metabolic syndrome are dominant in men.

Variability in the leptin receptor gene and other risk factors for post-transplant diabetes mellitus in renal transplant recipients

Aim: Post-transplant diabetes mellitus (PTDM) is one of the main complications after kidney transplantation. It is known that leptin plays an important role in glucose metabolism and mutations in the leptin receptor gene (LEPR) are responsible for different complications in renal transplant recipients. We aimed to analyse the association of polymorphisms in LEPR with the development of PTDM in these patients. Methods: A total of 315 renal transplant recipients were genotyped for the Lys109Arg, Gln223Arg and Lys656Asn polymorphisms. The impact of these genetic variables together with other clinical and demographic parameters on PTDM risk was evaluated in a multivariate regression analysis. Results: The 223Arg variant showed a significant association with PTDM risk [OR = 3.26 (1.35-7.85), p = 0.009] after correcting for multiple testing. Carriers of this variant also showed higher BMI values (26.95 ± 4.23) than non-carriers (25.67 ± 4.43, p = 0.025). In addition, it was BMI at transplant and not the BMI increment in the first year after grafting that was associated with PTDM (p > 0.00001). Haplotype analyses did not reveal significant associations. Conclusions: Our result show, for the first time to our knowledge, that genetic variability in the LEPR may contribute significantly to the risk for PTDM in renal transplant recipients. KEY MESSAGES The LEPR Gln223Arg polymorphism significantly contributes to the development of PTDM in renal transplant recipients. The effect of the 223Arg variant on PTDM is strongly modulated by the age of the recipient. The 223Arg variant in the leptin receptor is related to higher BMI in renal transplant recipients.

New-Onset Diabetes After Renal Transplantation (NODAT): Is It a Risk Factor for Renal Cell Carcinoma or Renal Failure?

Background

Diabetes mellitus (DM) is a risk factor for renal failure and possibly for renal cell carcinoma (RCC). Post-transplantation DM occurs frequently after solid organ transplantation. We investigated whether new-onset diabetes after renal transplantation (NODAT) is a risk factor for RCC or renal failure.

Material/Methods

Data of 96,699 discharged patients with and without NODAT were extracted from the 2005–2014 Nationwide Inpatient Sample (NIS) database, after excluding patients with DM diagnosed at least 1 year prior to renal transplantation. Main outcomes were RCC diagnosis less than 1-year post-transplantation, RCC stage, and renal failure. Univariate and multivariate regression analyses were performed to identify demographic and clinical factors associated with post-transplantation RCC or renal failure.

Results

Significant differences were found in age and race between patients with and without NODAT (both P<0.001). The renal failure rate was 0.8% (n=1) in NODAT patients and 0.3% (n=314) in those without NODAT. Older age (OR, 1.030; 95% CI: 1.023 to 1.036), male (OR, 1.872; 95% CI: 1.409 to 2.486), Black (OR, 2.199; 95% CI: 1.574 to 3.071) and hospitalization in urban teaching hospitals were associated with increased risk of RCC.

Conclusions

Analysis of over 90,000 NIS hospitalizations with diagnosis-coded kidney transplantation suggested that NODAT may not be an independent risk factor for RCC and renal failure.

Microvascular Complications of Posttransplant Diabetes Mellitus in Kidney Transplant Recipients: A Longitudinal Study

OBJECTIVE

To assesses microvascular complications in renal transplant recipients with posttransplant diabetes mellitus (PTDM).

RESEARCH DESIGN AND METHODS

In this observational study, patients with ≥5 years of PTDM were included from a cohort of 895 kidney recipients transplanted from 2000 through 2011. Diabetic retinopathy was evaluated by fundus photographs and optical coherence tomography (OCT). Diabetes kidney disease was evaluated by protein to creatinine ratio (PCR) and estimated glomerular filtration rate (eGFR). Distal polyneuropathy was assessed by Michigan Protocol and 10 g-monofilament feet examinations. The Ewing protocol identified cardiovascular autonomic neuropathy. Renal transplant recipients without PTDM diagnosis (NPTDM) were considered controls.

RESULTS

After 144.5 months of follow-up, 135 (15%) patients developed PTDM, and 64 had a PTDM duration ≥5 years. None of the patients with PTDM presented diabetic retinopathy at fundus photographs, but thinning of inner retinal layers was observed with OCT. More than 60% of patients with PTDM had distal polyneuropathy (OR, 1.55; 95% CI, 1.26 to 1.91; P < 0.001). Cardiovascular reflex tests abnormalities were similar between patients with PTDM and NPTDM (P = 0.26). During the first year and 8.5 ± 3.0 years after renal transplantation, eGFR and PCR did not differ significantly between patients with PTDM or NPTDM.

CONCLUSIONS

This longitudinal study assesses microvascular complications in renal transplant patients with PTDM. A lower than expected prevalence as well as a different clinical course of the complications was observed. PTDM seems to be a unique type of diabetes, and its consequences may be milder than expected in type 1 and type 2 diabetes.

Management of diabetes mellitus in patients undergoing liver transplantation

Diabetes is a common feature in cirrhotic individuals both before and after liver transplantation and negatively affects prognosis. Certain aetiological agents of chronic liver disease and loss of liver function per se favour the occurrence of pre-transplant diabetes in susceptible individuals, whereas immunosuppressant treatment, changes in lifestyle habits, and donor- and procedure-related factors contribute to diabetes development/persistence after transplantation. Challenges in the management of pre-transplant diabetes include the profound nutritional alterations characterizing cirrhotic individuals and the limitations to the use of drugs with liver metabolism. Special issues in the management of post-transplant diabetes include the diabetogenic potential of immunosuppressant drugs and the increased cardiovascular risk characterizing solid organ transplant survivors. Overall, the pharmacological management of cirrhotic patients undergoing liver transplantation is complicated by the lack of specific guidelines reflecting the paucity of data on the impact of glycaemic control and the safety and efficacy of anti-hyperglycaemic agents in these individuals.

Pre, peri and posttransplant diabetes mellitus

PURPOSE OF REVIEW

The leading cause of death in both chronic kidney disease (CKD) and renal transplant patients is cardiovascular events. Post-transplant diabetes mellitus (PTx-DM), which is a major cardiovascular risk factor, is a metabolic disorder that affects 5.5-60.2% of renal allograft recipients by 1-year posttransplant (PTx). PTx-DM has been associated with a negative impact on patient and graft outcomes and survival.

RECENT FINDINGS

Individuals who develop PTx-DM are usually prone to this condition prior to and/or after developing CKD. Genetic factors, obesity, inflammation, medications and CKD all are risk factors for PTx-diabetes mellitus. The path to development of disease continues PTx frequently augmented by the use of diabetogenic maintenance immunosuppressive and some nonimmunosuppressive medications. These risk factors are usually associated with an increase in insulin resistance, a decrease in insulin gene expression and/or β-cell dysfunction and apoptosis.

SUMMARY

Some new anti-diabetes mellitus medications may help to improve the overall outcome; however, there is a real need for developing a preventive strategy. Identifying and targeting PTx-DM risk factors may help to guide the development of an effective programme. This could include the adoption of nondiabetogenic immunosuppressive protocols for high-risk patients.

Temporal Changes on the Risks and Complications of Posttransplantion Diabetes Mellitus Following Cardiac Transplantation

Background

Recent changes in the demographic of cardiac donors and recipients have modulated the rate and risk, associated with posttransplant diabetes mellitus (PTDM). We investigated the secular trends of the risk of PTDM at 1 year and 3 years after transplantation over 30 years and explored its effect on major outcomes.

Methods

Three hundred and three nondiabetic patients were followed for a minimum of 36 months, after a first cardiac transplantation performed between 1983 and 2011. Based on the year of their transplantation, the patients were divided into 3 eras: (1983-1992 [era 1], 1993-2002 [era 2], and 2003-2011 [era 3]).

Results

In eras 1, 2, and 3, the proportions of patients with PTDM at 1 versus 3 years were 23% versus 39%, 21% versus 26%, and 33% versus 38%, respectively. Independent risk factors predicting PTDM at one year were recipient's age, duration of cold ischemic time, treatment with furosemide, and tacrolimus. There was a trend for overall survival being worse for patients with PTDM in comparison to patients without PTDM (p = 0.08). Patients with PTDM exhibited a significantly higher rate of renal failure over a median follow-up of 10 years (p = 0.03).

Conclusion

The development of PTDM following cardiac transplantation approaches 40% at 3 years and has not significantly changed over thirty years. The presence of PTDM is weakly associated with an increased mortality and is significantly associated with a worsening in renal function long-term following cardiac transplantation.

Mannose-binding lectin genotypes and outcome in end-stage renal disease: a prospective cohort study

Background

Patients with end-stage renal disease (ESRD) have high morbidity and mortality rates, with cardiovascular diseases and infections being the major causes of death. Mannose-binding lectin (MBL) has been suggested to play a protective role in this regard. The aim of this study was to investigate a possible clinical association of MBL genotypes (MBL2) with outcome among patients on dialysis or with a functioning graft.

Methods

A total of 98 patients with ESRD accepted for living-donor renal transplantation or on the waiting list for transplantation were included and prospectively followed for an average of 9 years (range 7.5-9.9). Medical records were evaluated regarding transplantation status, diabetes mellitus, vascular parameters and infections for all the patients. Cox regression models and logistic regression analysis were used for statistical analyses. The cohort was divided into two groups according to the MBL2 genotype (normal A/A versus variant A/O or O/O).

Results

We found no evidence for an association between the MBL2 genotype and all-cause mortality, cardiovascular events or bacterial infections (pneumonia, urinary tract infection, fistula infection or other infections).

Conclusion

In this cohort, the MBL2 genotype did not seem to be associated with any long-term clinical effects in ESRD patients on dialysis or with a functioning graft.

Randomized Controlled Trial Assessing the Impact of Tacrolimus Versus Cyclosporine on the Incidence of Posttransplant Diabetes Mellitus

INTRODUCTION

Despite the high incidence of posttransplant diabetes mellitus (PTDM) among high-risk recipients, no studies have investigated its prevention by immunosuppression optimization.

METHODS

We conducted an open-label, multicenter, randomized trial testing whether a tacrolimus-based immunosuppression and rapid steroid withdrawal (SW) within 1 week (Tac-SW) or cyclosporine A (CsA) with steroid minimization (SM) (CsA-SM), decreased the incidence of PTDM compared with tacrolimus with SM (Tac-SM). All arms received basiliximab and mycophenolate mofetil. High risk was defined by age >60 or >45 years plus metabolic criteria based on body mass index, triglycerides, and high-density lipoprotein-cholesterol levels. The primary endpoint was the incidence of PTDM after 12 months.

RESULTS

The study comprised 128 de novo renal transplant recipients without pretransplant diabetes (Tac-SW: 44, Tac-SM: 42, CsA-SM: 42). The 1-year incidence of PTDM in each arm was 37.8% for Tac-SW, 25.7% for Tac-SM, and 9.7% for CsA-SM (relative risk [RR] Tac-SW vs. CsA-SM 3.9 [1.2-12.4; P = 0.01]; RR Tac-SM vs. CsA-SM 2.7 [0.8-8.9; P = 0.1]). Antidiabetic therapy was required less commonly in the CsA-SM arm (P = 0.06); however, acute rejection rate was higher in CsA-SM arm (Tac-SW 11.4%, Tac-SM 4.8%, and CsA-SM 21.4% of patients; cumulative incidence P = 0.04). Graft and patient survival, and graft function were similar among arms.

CONCLUSION

In high-risk patients, tacrolimus-based immunosuppression with SM provides the best balance between PTDM and acute rejection incidence.

Inhibition of peptidyl-prolyl cis-trans isomerase B mediates cyclosporin A-induced apoptosis of islet β cells

Cyclosporin A (CsA) is widely used as an immunosuppressor in the context of organ transplantation or autoimmune disorders. Recent studies have revealed the detrimental effects of CsA on insulin resistance and pancreatic β cell failure; however, the molecular mechanisms are unknown. The present study sought to confirm the associations between CsA and β cell failure, and to investigate the roles of proinsulin folding and endoplasmic reticulum (ER) stress in CsA-induced β cell failure. The viability of MIN6 cells treated with CsA was evaluated with MTT assay. Expression levels of insulin, peptidyl-prolyl cis-trans isomerase B (PPIB), cleaved caspase-3, phospho-protein kinase R (PKR)-like endoplasmic reticulum kinase (p-PERK), PKR-like endoplasmic reticulum kinase (PERK), binding immunoglobulin protein (BIP), and C/EBP homologous protein (CHOP) were detected via reducing western blot assay. Non-reducing western blot analysis was performed to examine the expression of misfolded proinsulin peptides. The proliferation of MIN6 cells was not inhibited by CsA at concentrations <1 µmol/l. CsA treatment resulted in the decreased expression of insulin and PPIB; however, it also increased the phosphorylation of PERK, and upregulated the expression of PERK, BIP, CHOP and cleaved caspase-3. The results indicated that CsA could induce pancreatic β cell dysfunction and the potential mechanism underlying this phenomenon may be PPIB-associated proinsulin misfolding, which in turn induces ER stress in β cells.