Incidence of Recurrent NASH-Related Allograft Cirrhosis

Recurrence of Primary Disease After Adult Liver Transplant - Risk Factors, Early Diagnosis, Management, and Prevention

Liver transplantation offers a new lease of life to patients with end-stage liver disease and hepatocellular carcinoma. However, the implantation of an exogenous allograft and the accompanying immunosuppression bring their own challenges. Moreover, the persistence of risk factors for the initial liver insult place the new graft at a higher risk of damage. With the increasing number of liver transplants along with the improvement in survival posttransplant, the recurrence of primary disease in liver grafts has become more common. Pre-2015, the most common disease to recur after transplant was hepatitis C. However, directly acting antivirals have nearly eliminated this problem. The greatest challenge of disease recurrence we now face are those of nonalcoholic steatohepatitis, alcohol-related liver disease, and primary sclerosing cholangitis. We focus on the epidemiology and pathophysiology of the recurrence of primary disease after transplant. We also discuss means of early identification, risk stratification, prevention, and management of recurrent primary disease after liver transplantation.

The Outcomes of Liver Transplantation in Severe Metabolic Dysfunction-Associated Steatotic Liver Disease Patients

The increasing prevalence of diabetes mellitus, obesity, and metabolic syndrome in the population can lead to metabolic dysfunction-associated steatohepatitis (MASH) and metabolic dysfunction-associated steatotic liver disease (MASLD). In Western industrialized countries, this has become a major problem with significant socioeconomic impacts. MASH is now a leading cause of liver transplantation (LT), especially in developed countries. However, the post-transplant outcomes of such patients are a major concern, and published data are limited and extremely variable. In this article, we discuss graft and patient survival after LT, complications, the recurrence of MASH, and MASH appearing de novo after transplantation. Recent studies suggest that patients with MASH have slightly worse short-term survival, potentially due to increased cardiovascular mortality. However, most studies found that longer-term outcomes for patients undergoing LT for MASH are similar or even better than those for other indications. Hepatocellular carcinoma due to MASH cirrhosis also has similar or even better outcomes after LT than other etiologies. In conclusion, we suggest questions and topics that require further research to enhance healthcare for this growing patient population.

Long Term Complications of Immunosuppression Post Liver Transplant

Improvement in immunosuppression has led to a remarkable improvement in short-term and long-term outcomes post-liver transplant (LT). However, with improvements in long-term survival, complications related to immunosuppressive drugs, either directly or indirectly, have also increased. The adverse events could be drug-specific, class-specific, or generic. Calcineurin inhibitors (cyclosporine and tacrolimus) are the backbone of the immunosuppression after LT and the main culprit associated with most of the complications, including renal failure, post-transplant diabetes mellitus (PTDM), and metabolic syndrome. Steroids are also implicated in the development of diabetes, osteoporosis, and metabolic syndrome post-LT. The development of infections and de novo malignancies (DNMs) is a generic effect linked to the overall cumulative immunosuppression. The development of these complications significantly hampers the quality of life and leads to increased morbidity and mortality post-LT. Thus, it is important to minimize the cumulative immunosuppression dose while simultaneously preventing allograft rejection. This review provides up-to-date, comprehensive knowledge of the complications of long-term immunosuppression post-LT along with associated risk factors and strategies to minimize the risk of complications.

Mortality and Cardiovascular Outcomes in Adult Non-Liver Solid Organ Transplant Patients With Nonalcoholic Steatohepatitis

BACKGROUND

The effect of nonalcoholic steatohepatitis (NASH) on mortality or major adverse cardiovascular events (MACE) in non-liver solid organ transplant recipients (NL-SOT) is unknown.

METHODS

Using a retrospective design, adult NL-SOT recipients who had biopsy-proven NASH were compared NL-SOT recipients with normal liver function tests and imaging; propensity matched at a 1:10 ratio on the following: age, sex, race, transplant year, transplant organ, smoking status, and diabetes status. Both deceased and living donor recipients were included; heart and liver transplant patients were excluded. Primary outcome was incidence of all-cause mortality and MACE (a composite outcome of coronary artery disease, ischemic stroke, and peripheral arterial disease).

RESULTS

Seven patients (3 kidney and 4 lung transplants) had biopsy-proven NASH and 70 patients without NASH, both groups were predominantly male (53%-57%), White (86%-91%), and overweight (mean body mass index ∼ 26). The majority of patients were on calcineurin inhibitors (≥85%), antimetabolites (≥97%), and prednisone (≥50%). Survival analysis showed that NASH patients had a higher risk of death (hazard ratio [HR], 3.24; 95% confidence interval [CI], 1.26-8.33, P = 0.02). NASH did not affect the risk of death-censored graft failure (HR, 1.08; 95% CI, 0.14-8.67; P = .94) or the risk of MACE (HR, 1.03; 95% CI, 0.23-4.62; P = .97).

CONCLUSIONS

In NL-SOT recipients, NASH is significantly associated with mortality but not with MACE.

A Comprehensive Review of Liver Allograft Fibrosis and Steatosis: From Cause to Diagnosis

Despite advances in posttransplant care, long-term outcomes for liver transplant recipients remain unchanged. Approximately 25% of recipients will advance to graft cirrhosis and require retransplantation. Graft fibrosis progresses in the context of de novo or recurrent disease. Recurrent hepatitis C virus infection was previously the most important cause of graft failure but is now curable in the majority of patients. However, with an increasing prevalence of obesity and diabetes and nonalcoholic fatty liver disease as the most rapidly increasing indication for liver transplantation, metabolic dysfunction-associated liver injury is anticipated to become an important cause of graft fibrosis alongside alloimmune hepatitis and alcoholic liver disease. To better understand the landscape of the graft fibrosis literature, we summarize the associated epidemiology, cause, potential mechanisms, diagnosis, and complications. We additionally highlight the need for better noninvasive methods to ameliorate the management of graft fibrosis. Some examples include leveraging the microbiome, genetic, and machine learning methods to address these limitations. Overall, graft fibrosis is routinely seen by transplant clinicians, but it requires a better understanding of its underlying biology and contributors that can help inform diagnostic and therapeutic practices.

Hepatic steatosis after liver transplantation: a systematic review and meta-analysis

NAFLD can occur after liver transplantation (LT), as recurrence or de novo hepatic steatosis (HS). We aimed to evaluate the literature on prevalence, risk factors, and prognosis of post-LT HS. Systematic review with meta-analysis through a search on: PUBMED, Scopus, and Web-of-Science, from inception until the September 30, 2021. Forty studies were included, representing 6979 patients. The post-LT HS prevalence was 39.76% (95% CI, 34.06-45.46), with a rising kinetics (11.06% increase per decade, p =0.04), and a geographical distribution (15.10% more prevalent in American continent compared with Europe and Asia). Recurrent HS was up to 5-fold more likely than de novo HS [OR: 5.38 (2.69-10.76)]. Metabolic disturbances were stronger risk factors in the post-LT recipient [obesity: OR: 4.62 (3.07-6.96); metabolic syndrome: OR: 3.26 (2.03-5.25)] as compared with pre-LT recipients, with the exception of diabetes mellitus, which doubled the risk at any set [pre-LT diabetes mellitus: OR: 2.06 (1.58-2.68); post-LT diabetes mellitus: OR: 2.12 (1.73-2.59)]. Donor factors were not the relevant risk factors for post-LT HS and the only immunosuppressive drug associated with increased risk was sirolimus [OR: 1.68 (1.07-2.64)]. The prevalence of post-LT steatohepatitis was 28.82% (19.62-38.03) and the strongest risk factor was pre-LT NAFLD. Limited outcomes data suggest that post-LT HS did not increase the risk for liver cirrhosis or mortality in these studies. Two out of 5 patients submitted to LT will develop post-LT HS, being recurrent HS more common than de novo HS. Diabetes mellitus and post-LT metabolic syndrome are the strongest risk factors for HS and baseline NAFLD for steatohepatitis. All transplanted patients should be enrolled in lifestyle interventions to prevent post-LT metabolic syndrome, and sirolimus should be avoided in high-risk patients.

The Burden of Nonalcoholic Steatohepatitis: A Systematic Review of Epidemiology Studies

Background and Aims

Nonalcoholic steatohepatitis (NASH) is associated with increased mortality and risk of complications but is often asymptomatic and under-recognized. A systematic review of NASH epidemiology was conducted to provide information on the burden of NASH and highlight important evidence gaps for future research.

Methods

Medline, EMBASE, and Cochrane Library databases were searched for English-language publications published from 2010 to January 2022 that reported on natural history, risk factors, comorbidities, and complications of a NASH population or subpopulation.

Results

Overall, 173 publications were included. NASH was shown to have a variable disease course and high prevalence of comorbid disease. Although many patients progressed to cirrhosis and end-stage liver disease, disease regression or resolution was reported in up to half of patients in some studies. Reported risk factors for disease progression or resolution included levels of (or changes in) serum fibrosis markers, liver enzymes, and platelets. The presence of NASH increased the risk of liver cirrhosis and other serious diseases such as hepatocellular carcinoma, colorectal cancer, chronic kidney disease, and cardiovascular disease. In 2017, NASH was responsible for ∼118,000 cirrhosis deaths globally, and an increasing proportion of patients are receiving liver transplantation for NASH in Europe and the United States. Consolidation of data was hampered by heterogeneity across the studies in terms of patient populations, follow-up time, and outcomes measured.

Conclusion

NASH is associated with significant morbidity and mortality, an increased risk of comorbidities, and imposes an increasing burden among liver transplantation recipients. Longer studies with harmonized study criteria are required to better understand the impact of NASH on patient outcomes.

Utility of Metabolomic Biomarkers to Identify Nonalcoholic Fatty Liver Disease in Liver Transplant Recipients

Nonalcoholic fatty liver disease (NAFLD) is a rising indication for liver transplantation (LT). Identification of NAFLD recurrence and those at risk for more progressive disease after LT remains elusive as the diagnosis requires biopsy, which is invasive and impractical for serial monitoring. We therefore aimed to identify metabolites in the blood associated with recurrent NAFLD that could potentially be used for detection and monitoring.

Potential Bias and Misconceptions in Liver Transplantation for Alcohol- and Obesity-Related Liver Disease

INTRODUCTION

Bias and misconceptions surrounding alcohol-related liver disease (ALD) and obesity-related liver disease (OLD) may lead to transplant listing inequities. The aim of this study was to evaluate patients, medical students, residents, fellows, and attending physicians for bias and misconceptions regarding liver transplantation (LT) for patients with ALD and OLD.

METHODS

Participants took a survey asking them whether patients with ALD who continue/discontinue drinking alcohol or patients with OLD who do/do not commit to a weight loss program deserve equal LT rights. A Likert scale was used for their responses. Participants also estimated 5-year survival and advanced fibrosis recurrence after LT. The primary outcome of the study was bias measured by expected agreement or disagreement to questions using a Likert scale, significant underestimation of a 5-year survival rate after LT, and significant overestimation of 5-year advanced fibrosis recurrence after LT.

RESULTS

A total of 381 participants were included in the analysis: 153 residents/fellows, 31 attending physicians, 98 medical students, and 99 patients. A higher percentage from all 4 participating groups either were neutral or disagreed with equal LT rights for patients with ALD who discontinue drinking compared with patients with OLD who commit to weight loss program. The attending physician group was the only group with a majority estimating >60% 5-year survival after LT in patients with ALD and OLD (P < 0.05). All 4 groups had a majority estimate >20% 5-year advanced fibrosis recurrence in patients with ALD and OLD (P > 0.05).

DISCUSSION

There seems to be current bias and misconceptions regarding LT for patients with ALD and OLD.

Management of Patients With Non-alcoholic Steatohepatitis Undergoing Liver Transplantation: Considerations for the Anesthesiologist

Non-alcoholic fatty liver disease (NAFLD) currently affects more than 25% of the world population and is rising. NAFLD can progress to non-alcoholic steatohepatitis that is associated with hepatic inflammation and fibrosis and can result in cirrhosis with subsequent liver failure. Non-alcoholic steatohepatitis (NASH) has now emerged as one of the leading etiologies for a liver transplant among adults in the United States. Given the rising incidence of liver transplants in patients with NASH-related cirrhosis, it is essential for anesthesiologists to be familiar with this condition as well as with NASH-related comorbidities and perioperative complications. Not only is NASH linked to metabolic syndrome, but it also is independently associated with cardiovascular disease, renal and thyroid dysfunction, obstructive sleep apnea (OSA), and a hypercoagulable state. The association with these conditions can affect the perioperative outcome of these patients, particularly because of increased mortality from major adverse cardiovascular events and sepsis. In order to decrease the perioperative morbidity and mortality of patients with NASH undergoing a liver transplant, a multidisciplinary approach to their perioperative management is essential, along with careful preoperative evaluation and aggressive intraoperative and postoperative monitoring. The focus of this review article is to provide a comprehensive overview of challenges associated with liver transplants in patients with NASH and to provide suggestions for appropriate patient selection and perioperative management.

Clinical and Genetic Risk Factors of Recurrent Nonalcoholic Fatty Liver Disease After Liver Transplantation

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) has been increasingly reported among recipients of liver transplantation (LT). We aimed to identify clinical and genetic risk factors responsible for the development of early recurrent NAFLD in nonalcoholic steatohepatitis transplant recipients.

METHODS

Forty-six total single nucleotide polymorphisms with known association with NAFLD were tested among both recipient and donor liver samples in 66 LT recipients with nonalcoholic steatohepatitis to characterize influences on NAFLD recurrence at ∼1 year post-LT (median interval from LT to biopsy: 377 days).

RESULTS

Recurrent NAFLD was identified in 43 (65.2%) patients, 20 (30.3%) with mild recurrence, and 23 (34.8%) with moderate to severe NAFLD. On adjusted analysis, change in the body mass index (BMI) (ΔBMI) was significantly associated with NAFLD recurrence, whereas post-LT diabetes mellitus was associated with increased severity of NAFLD recurrence. ADIPOR1 rs10920533 in the recipient was associated with increased risk of moderate to severe NAFLD recurrence, whereas the minor allele of SOD2 rs4880 in the recipient was associated with reduced risk. Similar reduced risk was noted in the presence of donor SOD2 rs4880 and HSD17B13 rs6834314 polymorphism.

DISCUSSION

Increased BMI post-LT is strongly associated with NAFLD recurrence, whereas post-LT diabetes mellitus was associated with increased severity of NAFLD recurrence. Both donor and recipient SOD2 rs4880 and donor HSD17B13 rs6834314 single nucleotide polymorphisms may be associated with reduced risk of early NAFLD recurrence, whereas presence of the minor allele form of ADIPOR1 rs10920533 in the recipient is associated with increased severity NAFLD recurrence.

Obesity Management of Liver Transplant Waitlist Candidates and Recipients

Obesity is increasing in prevalence in liver transplant candidates and recipients. The rise in liver transplantation for nonalcoholic steatohepatitis reflects this increase. Management of obesity in liver transplant candidates can be challenging due to the presence of decompensated cirrhosis and sarcopenia. Obesity may increase peritransplant morbidity but does not have an impact on long-term post-transplant survival. Bariatric surgery may be a feasible option in select patients before, during, or after liver transplantation. Use of weight loss drugs and/or endoscopic therapies for obesity management ultimately may play a role in liver transplant patients, but more research is needed to determine safety.

Nonalcoholic steatohepatitis recurrence after liver transplant

Nonalcoholic steatohepatitis (NASH) is the fastest growing indication for liver transplant (LT)worldwide and is deemed to be the foremost indication in the near future. Recurrence of NASH can occur post LT and has been observed to be a common phenomenon. Baseline metabolic co-morbidities and worsening of metabolic profile post LT are the principal drivers of NASH recurrence. Liver biopsy remains the gold standard for establishing the diagnosis. However, noninvasive methods including transient elastography (TE) and magnetic resonance imaging (MRI) seem to be promising. The implications of recurrent NASH on post LT outcomes, graft steatosis, progression to fibrosis, overall survival, and cardiovascular associations warrant careful evaluation. Control of metabolic parameters and weight gain along with tailored immunosuppression remain the cornerstone of management. Extrapolation of the ever-increasing armamentarium of NASH pharmacotherapy specifically in this population of recurrent NAFLD remains a challenge for the future.