Changes in lipid and carbohydrate metabolism under mTOR- and calcineurin-based immunosuppressive regimen in adult patients after liver transplantation

The Effects of Sustained Immunosuppression Withdrawal After Liver Transplantation on Metabolic Syndrome

BACKGROUND

Liver transplant (LT) recipients often experience adverse effects of immunosuppressive (IS) drugs, especially on metabolic profiles. Selected LT recipients can achieve successful IS withdrawal; however, its effects on metabolic syndrome (MS) are unknown.

METHODS

This is a retrospective single-center study investigating the incidence and/or regression of MS in 75 selected LT recipients who were previously enrolled in prospective IS withdrawal trials between 1999 and 2017. Patients who were transplanted due to nonalcoholic steatohepatitis/metabolic-associated fatty liver disease were excluded, as well as those with a follow-up <3 y after IS weaning.

RESULTS

Forty-four patients (58.7%) achieved sustained withdrawal or minimization of immunosuppression (WMIS) and 31 patients (41.3%) required reintroduction of immunosuppression (no-WMIS). Among LT recipients who were metabolically healthy (n = 52, 69.3%) before the start of IS weaning, there was a significantly lower rate of de novo MS in WMIS patients compared with no-WMIS patients after 5 y (8.3% and 47.8%, respectively, P  = 0.034). Of 23 LT recipients (30.7%) who had MS at the time of commencing IS withdrawal, complete regression of MS was observed in 47.1% of WMIS patients and in none (0%) of the no-WMIS patients after 5 y ( P  = 0.054). Furthermore, individual components of MS were better controlled in IS-weaned patients, such as arterial hypertension and abnormal serum lipids.

CONCLUSIONS

Achievement of sustained IS withdrawal reduces the incidence of de novo MS development in metabolically healthy patients and increases the likelihood of MS regression in patients with established MS. The foreseeable long-term beneficial effects of these favorable metabolic changes on morbidity and mortality of LT recipients require further investigation.

The therapeutic effect of liver transplantation in 14 children with homozygous familial hypercholesterolemia: A prospective cohort: Liver transplant for familial hypercholesterolemia

OBJECTIVES

Homozygous familial hypercholesterolemia (HoFH) is characterized by elevated low-density lipoprotein cholesterol (LDL-C) and early-onset cardiovascular disease. To assess the therapeutic effects of liver transplantation (LT) on HoFH patients, we observed and analyzed the outcomes of HoFH children after LT.

STUDY DESIGN

This prospective cohort study included all LT candidates under 18 years old diagnosed with HoFH at Ren Ji Hospital between November 2017 and July 2021. The patients were followed until October 2023. They were treated according to the standard protocol at our center. We collected data on changes in lipid profiles, clinical manifestations, and cardiovascular complications at different time points, and recorded postoperative recipient and graft survival.

RESULTS

Fourteen HoFH patients with a median age of 7 (2-12) years were included. Preoperatively, xanthomas and arcus corneas occurred in 14 and 3 patients, respectively, with 10 patients showing mild cardiovascular disease. All patients underwent LT. Recipient and graft survival rates were 100% over a median follow-up duration of 35 (27-71) months. Median LDL-C levels dropped from 11.83 (7.99-26.14) mmol/L preoperatively to 2.3 (1.49-3.39) mmol/L postoperative at the last measurement. Thirteen patients discontinued lipid-lowering treatment after LT, while only one patient resumed statins 6 months post-operation. Xanthomas and arcus corneas significantly improved. Cardiovascular complications regressed in five patients, with no progression observed in the others.

CONCLUSIONS

LT is a safe and effective treatment for severe HoFH patients beyond lipid-lowering control. Early LT improves prognosis and quality of life while minimizing the risk of cardiovascular complications.

Post-Liver Transplant Metabolic Syndrome

Non-alcoholic steatohepatitis (NASH) is the second most frequent cause of liver transplantation following alcoholic liver disease. With longer follow-up and increased survival rates, the occurrence rate of the metabolic syndrome is increasing with time among liver transplant recipients. Reappearances of non-alcoholic fatty liver disease after transplantation, both as recurring cases and new instances, are prevalent; nonetheless, the recurrence of fibrosis is minimal. Recognizing populations at elevated risk and enhancing the management of metabolic-related conditions are crucial for maintaining a healthy transplanted organ, particularly considering the prolonged utilization of immunosuppressive treatments. Furthermore, NASH-related cirrhosis patients who had transplant are at a greater risk of cardiovascular, renal events and increased incidence of cancer, necessitating a unique care strategy. This review discusses post-transplant metabolic syndrome, risk factors, pathogenesis, diagnosis, prevention strategy, recurrent and de novo NAFLD and customized immunosuppression.

Stroke and kidney transplantation

PURPOSE OF REVIEW

This review will focus on the epidemiological data, risk factors, and management of stroke before and after kidney transplant. Stroke is highly prevalent in waitlisted patients as well as kidney transplant recipients and is associated with impaired transplant outcomes. Multiple traditional, nontraditional, and transplanted risk factors increase the risk of stroke.

RECENT FINDINGS

Although the risk of stroke is reduced after kidney transplantation compared with remaining on dialysis, the morbidity and mortality from stroke after transplantation remain significant.

SUMMARY

Early screening for risk factors before and after a kidney transplant and following the Kidney Disease Improving Global Outcomes (KDIGO) management guidelines could minimize the incidence of stroke and transplant outcomes.

Combination of everolimus and low-dose tacrolimus controls histological liver allograft injury as sufficiently as high-dose tacrolimus

Introduction

The combination of everolimus (EVR) and low-dose tacrolimus (lowTAC) prevents T cell-mediated rejection of liver grafts as sufficiently as high-dose tacrolimus (highTAC) and mycophenolate, but is associated with a preserved kidney function within the first years after orthotopic liver transplantation (OLT). However, none of the available studies assessed the histological pattern of graft injury or fibrosis in surveillance biopsies (svLbx).

Methods

All svLbx taken under at least one month of stable immunosuppression with either EVR (aim 3-8 ng/ml) combined with lowTAC (aim 3-5 ng/ml) or highTAC (aim 5-8 ng/ml) combined with mycophenolate (500-1500 mg/day) within the first three to four years after OLT at our center were included. Patients who were switched to EVR because of insufficient control of alloreactivity were excluded.

Results

Reasons for switches to EVR were mainly malignancies before or after OLT, or chronic kidney injury. We were able to include 20 svLbx with EVR/lowTAC and 49 with highTAC/mycophenolate. Both groups had similar liver enzymes and similar kidney function. The EVR/lowTAC group exhibited lower TAC trough levels at svLbx (4.4 vs. 6.6 ng/ml; p<.001) in comparison to highTAC/mycophenolate. Histological graft injury quantified by the rejection activity index and hepatitis activity index (Ishak), as well as fibrosis were not significantly different between the EVR/lowTAC and highTAC/mycophenolate groups. Likewise, subclinical TCMR, histological criteria justifying immunosuppression minimization, and steatosis had equal prevalence in both regimens. Immunosuppression was adjusted according to the svLbx findings. Immunosuppression regimens had similarly low rates of rejection after immunosuppression reduction, when relevant graft injury was absent in the biopsy.

Discussion

In conclusion, EVR/lowTAC seems to control alloreactivity and histological graft injury as sufficiently as highTAC/mycophenolate within the first 3-4 years after OLT.

De novo metabolic syndrome after liver transplantation: a meta-analysis on cumulative incidence, risk factors, and outcomes

Post-transplant metabolic syndrome (PTMS) has been associated with increased cardiovascular risk which significantly impacts the morbidity and mortality rates of liver transplant (LT) recipients. This study sought to conduct a meta-analysis and systematic review on the cumulative incidence, risk factors, and cardiovascular outcomes associated with de novo PTMS.Medline and Embase were searched for articles describing the incidence, risk factors, and cardiovascular outcomes of de novo PTMS. Meta-analysis of proportions was conducted to calculate incidence. Conventional pairwise analysis using random effects model was used to tabulate OR and hazard ratio for risk factors and cardiovascular outcomes, respectively. Fifteen studies involving 2683 LT recipients were included. Overall rate of de novo PTMS was 24.7% (CI: 18.0%-32.9%) over a mean follow-up period of 15.3 months and was highest in patients with NAFLD (60.0%, CI: 52.0%-67.5%) compared with other liver diseases. Older age (OR: 1.05, CI: 1.01-1.09, p = 0.02) and pre-LT type II diabetes mellitus (OR: 5.00, CI: 4.17-5.99, p < 0.01) were predictive factors of de novo PTMS. Patients with de novo PTMS had significantly higher likelihood of cardiovascular disease events compared with those who did not (hazard ratio: 2.42, CI: 1.54-3.81, p < 0.01). De novo PTMS is a common complication and is significantly associated with increased cardiovascular disease morbidity. High-risk patients such as elderly recipients, those with pre-LT type II diabetes mellitus, or NASH-related cirrhosis should undergo routine screening to allow timely intervention.

Metabolic mechanisms for and treatment of NAFLD or NASH occurring after liver transplantation

The rising tide of non-alcoholic fatty liver disease (NAFLD) associated with the obesity epidemic is a major health concern worldwide. NAFLD - specifically its more advanced form, non-alcoholic steatohepatitis (NASH)-related cirrhosis - is now the fastest growing indication for liver transplantation in the USA and Europe. Although the short-term and mid-term overall survival rates of patients who receive a liver transplant for NASH-related cirrhosis are essentially similar to those of patients who receive a transplant for other liver indications, recipients with NASH-related cirrhosis have an increased risk of waiting-list mortality and of developing recurrent liver disease and cardiometabolic complications in the longer term after liver transplantation. This Review provides a brief overview of the epidemiology of NAFLD and NASH and the occurrence of NAFLD or NASH in patients after liver transplantation for NASH and other liver indications. It also discusses the putative metabolic mechanisms underlying the emergence of NAFLD or NASH after liver transplantation as well as optimal therapeutic approaches for recipients of liver transplants, including the management of cardiometabolic comorbidities, tailored immunosuppression, lifestyle changes and pharmacotherapy for NAFLD.

Haematological Drugs Affecting Lipid Metabolism and Vascular Health

Many drugs affect lipid metabolism and have side effects which promote atherosclerosis. The prevalence of cancer-therapy-related cardiovascular (CV) disease is increasing due to development of new drugs and improved survival of patients: cardio-oncology is a new field of interest and research. Moreover, drugs used in transplanted patients frequently have metabolic implications. Increasingly, internists, lipidologists, and angiologists are being consulted by haematologists for side effects on metabolism (especially lipid metabolism) and arterial circulation caused by drugs used in haematology. The purpose of this article is to review the main drugs used in haematology with side effects on lipid metabolism and atherosclerosis, detailing their mechanisms of action and suggesting the most effective therapies.

De novo and recurrence of metabolic dysfunction-associated fatty liver disease after liver transplantation

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a new acronym adopted from the consensus of international experts. Given the increasing prevalence of MAFLD in pre-transplant settings, de novo and recurrent graft steatosis/MAFLD are common in post-transplant settings. The impact of graft steatosis on long-term outcomes is unclear. The current knowledge of incidence rate, risk factors, diagnosis, long-term outcomes, and management of graft steatosis (both de novo and recurrent) is discussed in this review.

An observational study on the effect of hypercholesterolemia developed after living donor liver transplantation on cardiac event and graft failure

This study sought to evaluate the association between newly-developed significant hypercholesterolemia within one year following living donor liver transplantation (LDLT) and long term outcomes in light of cardiovascular events and graft failure. From October 2003 to July 2017, 877 LDLT recipients were stratified according to development of significant hypercholesterolemia within one year following LDLT. The primary outcome was occurrence of a major adverse cardiac event (MACE), defined as a composite of cardiac death, myocardial infarction, and coronary revascularization after LDLT. The incidence of graft failure, defined as all-cause death or retransplantation, was also compared. A total of 113 (12.9%) recipients developed significant hypercholesterolemia within one year. The differences in incidences of cardiac related events and graft related events began emerging significantly higher in the hypercholesterolemia group after 24 months and 60 months since the LDLT, respectively. After adjustment using the inverse probability of weighting, the hazard ratio (HR) for MACE was 2.77 (95% confidence interval (CI) 1.16–6.61; p = 0.02), while that for graft failure was 3.76 (95% CI 1.97–7.17, p < 0.001). A significant hypercholesterolemia after LDLT may be associated with cardiac and graft-related outcome; therefore, a further study and close monitoring of cholesterol level after LDLT is needed.

Metabolic syndrome following liver transplantation in nonalcoholic steatohepatitis

Metabolic syndrome is a major clinical disorder involving metabolic dysregulation characterized clinically with features of central obesity, insulin resistance (IR), type 2 diabetes, hypertension, and dyslipidemia. Metabolic syndrome is strongly associated with the rising prevalence nonalcoholic steatohepatitis, a leading indication for orthotopic liver transplantation in the Western world. The presence or recurrence of metabolic syndrome following liver transplantation can contribute to the development and recurrence of nonalcoholic fatty liver disease (NAFLD) in the liver allograft. In this review, we discuss the endogenous and exogenous drivers of post-transplant metabolic syndrome, role of chronic immunosuppression, and the prevalence and clinical significant of post-transplant metabolic syndrome on nonalcoholic steatohepatitis.

Approach to prevention of non-alcoholic fatty liver disease after liver transplantation

Non-alcoholic fatty liver disease (NAFLD) is one of the most common causes of liver disease and non-alcoholic steatohepatitis (NASH) related cirrhosis is third common indication for liver transplantation (LT). Patients who have NASH related cirrhosis and are candidates for LT often have multiple comorbidities. These comorbidities need to be addressed before and after transplantation as it affects overall survival. Like hepatitis B, hepatitis C, primary biliary cirrhosis, autoimmune hepatitis which recurs after transplantation, NASH also recurs after transplant however the impact of the recurrence on allograft and patient outcomes is unclear. Limited data suggests that it does not affect graft and patient survival. De novo NAFLD which is defined as occurrence of fatty liver in a patient who did not have fatty liver prior to LT can also occur in the allograft of patients transplanted for non-NAFLD liver disease. Obesity, hyperlipidemia, diabetes as well as steroid dose and duration after LT are common predictors of recurrence of NAFLD after transplantation. Studies on prevention and treatment of NASH in post-transplant patients are lacking. Prevention of weight gain, regular exercises, weight reducing surgery, limited steroid use or steroid free regimen have been tried with varying success. Future studies for the prevention of NAFLD/NASH are required especially in post liver transplant patient.

Sirolimus and mTOR Inhibitors: A Review of Side Effects and Specific Management in Solid Organ Transplantation

Inhibitors of mechanistic target of rapamycin (mTOR inhibitors) are used as antiproliferative immunosuppressive drugs and have many clinical applications in various drug combinations. Experience in transplantation studies has been gained regarding the side effect profile of these drugs and the potential benefits and limitations compared with other immunosuppressive agents. This article reviews the adverse effects of mTOR inhibitors in solid organ transplantation, with special attention given to mechanisms hypothesized to cause adverse events and their management strategies.

Nonalcoholic Steatohepatitis After Liver Transplantation

Currently, nonalcoholic steatohepatitis (NASH) is the second leading indication for liver transplantation (LT), behind alcohol-related liver disease. After transplant, both recurrent and de novo nonalcoholic fatty liver disease are common; however, recurrence rates of NASH and advanced fibrosis are low. Identification of high-risk groups and optimizing treatment of metabolic comorbidities both before and after LT is paramount to maintaining a healthy allograft, especially with the additional consequences of longterm immunosuppression. In addition, NASH LT recipients are at an increased risk of cardiovascular events and malignancy, and their condition warrants a tailored approach to management. The optimal approach to NASH LT recipients including metabolic comorbidities management, tailored immunosuppression, the role of bariatric surgery, and nutritional and pharmacotherapy of NASH are discussed in this review. Overall, aggressive management of metabolic syndrome after LT via medical and surgical modalities and a minimalist approach to immunosuppression is advised.

Weight Gain and De Novo Metabolic Disorders after Liver Transplantation

The development of nutritional and metabolic abnormalities represents an important burden in patients after liver transplantation (LT). Our study aimed at evaluating the incidence, time of onset, and risk factors for nutritional and metabolic abnormalities in patients after LT. The study was a single-center retrospective study. Consecutive patients undergoing elective LT from 2000 to 2016 were enrolled. The presence of at least two among arterial hypertension (AH), diabetes mellitus (DM), dyslipidemia, and obesity (BMI ≥ 30 Kg/m²) was utilized to define patients with the metabolic disorder (MD). Three hundred and fifteen patients were enrolled; the median age was 56 years (68% males). Non-alcoholic steatohepatitis (NASH) was the origin of liver disease in 10% of patients. During follow-up, 39% of patients developed AH, 18% DM, and 17% dyslipidemia. Metabolic disorders were observed in 32% of patients. The NASH etiology (OR: 6.2; CI 95% 0.5–3; p = 0.003) and a longer follow-up (OR: 1.2; CI 95% 0.004–0.02; p = 0.002) were associated with de novo MD. In conclusion, nutritional and metabolic disorders are a frequent complication after LT, being present in up to one-third of patients. The NASH etiology and a longer distance from LT are associated with de novo MD after LT.

Small Dense Low-Density Lipoprotein Cholesterol Predicts Cardiovascular Events in Liver Transplant Recipients

Cardiovascular disease (CVD) is an important cause of morbidity and mortality after liver transplantation (LT). Although LT is associated with dyslipidemia, particularly atherogenic lipoprotein subparticles, the impact of these subparticles on CVD-related events is unknown. Therefore, the aim of the current study was to evaluate the impact of small dense (sdLDL-C) low-density lipoprotein (LDL) cholesterol (LDL-C) on CVD events. Prospectively enrolled patients (N = 130) had detailed lipid profile consisting of traditional lipid parameters and sdLDL-C and were followed for CVD events. The primary endpoint was a CVD composite consisting of myocardial infarction (MI), angina, need for coronary revascularization, and cardiac death. Mean age of the cohort was 58 ± 11 years, and the most common etiology of liver disease (LD) was hepatitis C virus (N = 48) and nonalcoholic steatohepatitis (N = 23). A total of 20 CVD events were noted after median follow-up of 45 months. The baseline traditional profile was similar in patients with and without CVD events. A serum LDL-C cutoff of 100 mg/dL was unable to identify individuals at risk of a CVD event (P = 0.86). In contrast, serum concentration of atherogenic sdLDL-C >25 mg/dL was predictive of CVD events with a hazard ratio of 6.376 (95% confidence interval, 2.65, 15.34; P < 0.001). This relationship was independent of diabetes, hypertension, sex, ethnicity, LD, obesity, and statin use. Conclusion: sdLDL-C independently predicted CVD events whereas LDL-C did not. Thus, sdLDL-C may provide a useful clinical tool in risk stratifying and managing patients after LT.

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.

Nonalcoholic steatohepatitis before and after liver transplant: keeping up with the times

In the last years, nonalcoholic steatohepatitis (NASH) has become a leading indication for liver transplant (LT). After transplant, both recurrent and de novo nonalcoholic fatty liver disease (NAFLD) can be commonly diagnosed. However, dedicated surveillance programs for patients with pre- or post-transplant NAFLD are not available. Areas covered: Patients waiting for LT for NASH show specific peculiarities and would deserve targeted stratification of mortality risk. Obesity, hyperlipidemia, and diabetes mellitus can be often found after transplant. These conditions, together with immunosuppressive regimen, make LT recipients a high-risk population for both recurrent and de novo NAFLD. Development of fatty liver disease after LT has a relevant impact on both morbidity and mortality. Expert commentary: A targeted stratification of neoplastic and cardiovascular risk for patients with NASH waiting for LT would be mandatory. In both pre- and post-transplant period, NAFLD should be considered not only a liver disease but also a cardiovascular risk factor. Patients within Transplant Program, especially those with known metabolic risk factors, should be followed with personalized diagnostic and life-style interventions before and after LT.

De Novo and Recurrence of Nonalcoholic Steatohepatitis After Liver Transplantation

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in developing countries. Approximately 25% of patients with NAFLD develop nonalcoholic steatohepatitis (NASH). NASH-related cirrhosis is now a leading listing indication for liver transplantation in the United States. Although posttransplant survival for NASH-related cirrhosis is comparable with that of other liver diseases, many patients have features of metabolic syndrome, which can contribute to a recurrence of NAFLD or NASH. This article reviews the epidemiology, pathophysiology, and treatment of de novo and recurrence of NASH after liver transplantation.

Cardiovascular risk after orthotopic liver transplantation, a review of the literature and preliminary results of a prospective study

Improved surgical techniques and greater efficacy of new anti-rejection drugs have significantly improved the survival of patients undergoing orthotopic liver transplantation (OLT). This has led to an increased incidence of metabolic disorders as well as cardiovascular and cerebrovascular diseases as causes of morbidity and mortality in OLT patients. In the last decade, several studies have examined which predisposing factors lead to increased cardiovascular risk (i.e., age, ethnicity, diabetes, NASH, atrial fibrillation, and some echocardiographic parameters) as well as which factors after OLT (i.e., weight gain, metabolic syndrome, immunosuppressive therapy, and renal failure) are linked to increased cardiovascular mortality. However, currently, there are no available data that evaluate the development of atherosclerotic damage after OLT. The awareness of high cardiovascular risk after OLT has not only lead to the definition of new but generally not accepted screening of high risk patients before transplantation, but also to the need for careful patient follow up and treatment to control metabolic and cardiovascular pathologies after transplant. Prospective studies are needed to better define the predisposing factors for recurrence and de novo occurrence of metabolic alterations responsible for cardiovascular damage after OLT. Moreover, such studies will help to identify the timing of disease progression and damage, which in turn may help to prevent morbidity and mortality for cardiovascular diseases. Our preliminary results show early occurrence of atherosclerotic damage, which is already present a few weeks following OLT, suggesting that specific, patient-tailored therapies should be started immediately post OLT.

Non-Alcoholic Fatty Liver Disease and Metabolic Syndrome after Liver Transplant

Liver transplant is the unique curative therapy for patients with acute liver failure or end-stage liver disease, with or without hepatocellular carcinoma. Increase of body weight, onset of insulin resistance and drug-induced alterations of metabolism are reported in liver transplant recipients. In this context, post-transplant diabetes mellitus, hyperlipidemia, and arterial hypertension can be often diagnosed. Multifactorial illnesses occurring in the post-transplant period represent significant causes of morbidity and mortality. This is especially true for metabolic syndrome. Non-alcoholic steatosis and steatohepatitis are hepatic manifestations of metabolic syndrome and after liver transplant both recurrent and de novo steatosis can be found. Usually, post-transplant steatosis shows an indolent outcome with few cases of fibrosis progression. However, in the post-transplant setting, both metabolic syndrome and steatosis might play a key role in the stratification of morbidity and mortality risk, being commonly associated with cardiovascular disease. The single components of metabolic syndrome can be treated with targeted drugs while lifestyle intervention is the only reasonable therapeutic approach for transplant patients with non-alcoholic steatosis or steatohepatitis.