Nateglinide improves postprandial hyperglycemia and insulin secretion in renal transplant recipients

An update review of post-transplant diabetes mellitus: Concept, risk factors, clinical implications and management

OBJECTIVE

Kidney transplantation is the gold standard therapeutic alternative for patients with end-stage renal disease; nevertheless, it is not without potential complications leading to considerable morbidity and mortality such as post-transplant diabetes mellitus (PTDM). This narrative review aims to comprehensively evaluate PTDM in terms of its diagnostic approach, underlying pathophysiological pathways, epidemiological data, and management strategies.

METHODS

Articles were retrieved from electronic databases using predefined search terms. Inclusion criteria encompassed studies investigating PTDM diagnosis, pathophysiology, epidemiology, and management strategies.

RESULTS

PTDM emerges as a significant complication following kidney transplantation, influenced by various pathophysiological factors including peripheral insulin resistance, immunosuppressive medications, infections, and proinflammatory pathways. Despite discrepancies in prevalence estimates, PTDM poses substantial challenges to transplant. Diagnostic approaches, including traditional criteria such as fasting plasma glucose (FPG) and HbA1c, are limited in their ability to capture early PTDM manifestations. Oral glucose tolerance test (OGTT) emerges as a valuable tool, particularly in the early post-transplant period. Management strategies for PTDM remain unclear, within sufficient evidence from large-scale randomized clinical trials to guide optimal interventions. Nevertheless, glucose-lowering agents and life style modifications constitute primary modalities for managing hyperglycemia in transplant recipients.

DISCUSSION

The complex interplay between PTDM and the transplant process necessitates individualized diagnostic and management approaches. While early recognition and intervention are paramount, modifications to maintenance immunosuppressive regimens based solely on PTDM risk are not warranted, given the potential adverse consequences such as increased rejection risk. Further research is essential to refine management strategies and enhance outcomes for transplant recipients.

Treatment of Type 2 Diabetes Mellitus in Advanced Chronic Kidney Disease for the Primary Care Physician

Diabetes mellitus (DM) is a common cause of chronic kidney disease (CKD), leading to the need for renal replacement therapy (RRT). RRT includes hemodialysis (HD), peritoneal dialysis (PD), kidney transplantation (KT), and medical management. As CKD advances, the management of DM may change as medication clearance, effectiveness, and side effects can be altered due to decreasing renal clearance. Medications like metformin that were safe to use early in CKD may build up toxic levels of metabolites in advanced CKD. Other medications, like sodium-glucose co-transporter 2 inhibitors, which work by excreting glucose in the urine, may not be able to work effectively in advanced CKD due to fewer working nephrons. Insulin breakdown may take longer, and both formulation and dosing may need to be changed to avoid hypoglycemia. While DM control contributes to CKD progression, effective DM control continues to be important even after patients have been placed on RRT. Patients on RRT are frequently taken care of by a team of providers, including the primary care physician, both in and outside the hospital. Non-nephrologists who are involved with the care of a patient treated with RRT need to be adept at managing DM in this population. This paper aims to outline the management of type 2 DM in advanced CKD.

International consensus on post-transplantation diabetes mellitus

Post-transplantation diabetes mellitus (PTDM) remains a leading complication after solid organ transplantation. Previous international PTDM consensus meetings in 2003 and 2013 provided standardized frameworks to reduce heterogeneity in diagnosis, risk stratification and management. However, the last decade has seen significant advancements in our PTDM knowledge complemented by rapidly changing treatment algorithms for management of diabetes in the general population. In view of these developments, and to ensure reduced variation in clinical practice, a 3rd international PTDM Consensus Meeting was planned and held from 6-8 May 2022 in Vienna, Austria involving global delegates with PTDM expertise to update the previous reports. This update includes opinion statements concerning optimal diagnostic tools, recognition of prediabetes (impaired fasting glucose and/or impaired glucose tolerance), new mechanistic insights, immunosuppression modification, evidence-based strategies to prevent PTDM, treatment hierarchy for incorporating novel glucose-lowering agents and suggestions for the future direction of PTDM research to address unmet needs. Due to the paucity of good quality evidence, consensus meeting participants agreed that making GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) recommendations would be flawed. Although kidney-allograft centric, we suggest that these opinion statements can be appraised by the transplantation community for implementation across different solid organ transplant cohorts. Acknowledging the paucity of published literature, this report reflects consensus expert opinion. Attaining evidence is desirable to ensure establishment of optimized care for any solid organ transplant recipient at risk of, or who develops, PTDM as we strive to improve long-term outcomes.

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.

Post-transplant diabetes mellitus in patients with solid organ transplants

Solid organ transplantation (SOT) is a life-saving procedure and an established treatment for patients with end-stage organ failure. However, transplantation is also accompanied by associated cardiovascular risk factors, of which post-transplant diabetes mellitus (PTDM) is one of the most important. PTDM develops in 10-20% of patients with kidney transplants and in 20-40% of patients who have undergone other SOT. PTDM increases mortality, which is best documented in patients who have received kidney and heart transplants. PTDM results from predisposing factors (similar to type 2 diabetes mellitus) but also as a result of specific post-transplant risk factors. Although PTDM has many characteristics in common with type 2 diabetes mellitus, the prevention and treatment of the two disorders are often different. Over the past 20 years, the lifespan of patients who have undergone SOT has increased, and PTDM becomes more common over the lifespan of these patients. Accordingly, PTDM becomes an important condition not only to be aware of but also to treat. This Review presents the current knowledge on PTDM in patients receiving kidney, heart, liver and lung transplants. This information is not only for transplant health providers but also for endocrinologists and others who will meet these patients in their clinics.

Post-Liver Transplantation Diabetes Mellitus: A Review of Relevance and Approach to Treatment

Post-liver transplantation diabetes mellitus (PLTDM) develops in up to 30% of liver transplant recipients and is associated with increased risk of mortality and multiple morbid outcomes. PLTDM is a multicausal disorder, but the main risk factor is the use of immunosuppressive agents of the calcineurin inhibitor (CNI) family (tacrolimus and cyclosporine). Additional factors, such as pre-transplant overweight, nonalcoholic steatohepatitis and hepatitis C virus infection, may further increase risk of developing PLTDM. A diagnosis of PLTDM should be established only after doses of CNI and steroids are stable and the post-operative stress has been overcome. The predominant defect induced by CNI is insulin secretory dysfunction. Plasma glucose control must start immediately after the transplant procedure in order to improve long-term results for both patient and transplant. Among the better known antidiabetics, metformin and DPP-4 inhibitors have a particularly benign profile in the PLTDM context and are the preferred oral agents for long-term management. Insulin therapy is also an effective approach that addresses the prevailing pathophysiological defect of the disorder. There is still insufficient evidence about the impact of newer families of antidiabetics (GLP-1 agonists, SGLT-2 inhibitors) on PLTDM. In this review, we summarize current knowledge on the epidemiology, pathogenesis, course of disease and medical management of PLTDM.

HYPERGLYCEMIA MANAGEMENT IN PATIENTS WITH POSTTRANSPLANTATION DIABETES

OBJECTIVE

Posttransplantation diabetes (PTDM) is a common occurrence after solid-organ transplantation and is associated with increased morbidity, mortality, and health care costs. There is a limited number of studies addressing strategies for hyperglycemia management in this population, with a few articles emerging recently.

METHODS

We performed a PubMed search of studies published in English addressing hyperglycemia management of PTDM/new-onset diabetes after transplant (NODAT). Relevant cited articles were also retrieved.

RESULTS

Most of the 25 publications eligible for review were retrospective studies. Insulin therapy during the early posttransplantation period showed promise in preventing PTDM development. Thiazolidinediones have been mostly shown to exert glycemic control in retrospective studies, at the expense of weight gain and fluid retention. Evidence with metformin, sulfonylureas, and meglitinides is very limited. Incretins have shown promising results in small prospective studies using sitagliptin, linaglitpin, and vildagliptin and a case series using liraglutide.

CONCLUSION

Prospective randomized studies assessing the management of hyperglycemia in PTDM are urgently needed. In the meantime, clinicians need to be aware of the high risk of PTDM and associated complications and current concepts in management.

Emerging treatments for post-transplantation diabetes mellitus

Post-transplantation diabetes mellitus (PTDM), also known as new-onset diabetes mellitus (NODM), occurs in 10-15% of renal transplant recipients and is associated with cardiovascular disease and reduced lifespan. In the majority of cases, PTDM is characterized by β-cell dysfunction, as well as reduced insulin sensitivity in liver, muscle and adipose tissue. Glucose-lowering therapy must be compatible with immunosuppressant agents, reduced glomerular filtration rate (GFR) and severe arteriosclerosis. Such therapy should not place the patient at risk by inducing hypoglycaemic episodes or exacerbating renal function owing to adverse gastrointestinal effects with hypovolaemia. First-generation and second-generation sulphonylureas are generally avoided, and caution is currently advocated for the use of metformin in patients with GFR <60 ml/min/1.73 m(2). DPP-4 inhibitors do not interact with immunosuppressant drugs and have demonstrated safety in small clinical trials. Other therapeutic options include glinides and glitazones. Evidence-based treatment regimens used in patients with type 2 diabetes mellitus cannot be directly implemented in patients with PTDM. Studies investigating the latest drugs are required to direct the development of improved treatment strategies for patients with PTDM. This Review outlines the modern principles of glucose-lowering treatment in PTDM with specific reference to renal transplant recipients.

Prevention and management of transplant-associated diabetes

INTRODUCTION

New-onset diabetes after transplantation (NODAT) is considered to be a major cause of cardiovascular disease and death among patients with a functioning allograft. A major challenge is to reduce the incidence of NODAT and to treat it optimally once it has occurred.

AREAS COVERED

This review presents current data on how to prevent NODAT in patients at risk, with a focus on modifications in the immunosuppressive regimen. Current suggestions for detection and treatment of NODAT are also presented.

EXPERT OPINION

Prevention of NODAT is possible by assessing the patient's glycemic risk prior to transplantation and tailoring the treatment (e.g., choice and dosage of immunosuppressive agents) after transplantation. An oral glucose tolerance test is still the gold standard to detect NODAT in patients at risk (prediabetes) but algorithms can be used to select those who should be tested. The treatment of NODAT involves a broad approach on risk factors for cardiovascular events and graft loss. Future studies on the use of oral hypoglycemic agents in NODAT are still needed.