Liver-Related and Cardiovascular Outcome of Patients Transplanted for Nonalcoholic Fatty Liver Disease: A European Single-Center Study

Liver Allograft Cirrhosis, Retransplant, and Mortality Secondary to Recurrent Disease After Transplant for MASH: A Systematic Review and Meta-analysis

BACKGROUND

Recurrent disease after liver transplant is well recognized for many diseases. Metabolic dysfunction-associated steatotic liver disease (MASLD) and steatohepatitis (MASH) are leading indications for liver transplant, and there is scarce knowledge about recurrence-related end outcomes such as retransplant and mortality. This project aims to assess the proportion of patients transplanted for MASH who develop recurrent disease and adverse clinical outcomes.

METHODS

A systematic review and pooled proportions meta-analysis was performed by searching the following databases: MEDLINE, Embase, Scopus, Web of Science Core Collection, and Cochrane Library. Inclusion criteria were studies discussing adult patients with liver transplants secondary to MASH or presumed MASH with recurrent disease-related outcomes. Outcomes were assessed in time frames from <6 mo to ≥5 y.

RESULTS

Of 5859 records, 40 were included (16 157 patients). Recurrent MASLD and MASH (28 studies each) occurred in frequencies of 35%-49% and 11%-24%, respectively. Fibrosis occurred in 4%-25% (13 studies). Recurrent disease-related cirrhosis (13 studies), graft failure (8 studies), and retransplant (9 studies) occurred in 0%-2%, 3%-9%, and 0%-1%, respectively. Recurrent disease-related hepatocellular carcinoma (1 study) and mortality (17 studies) both had a prevalence of 0%. Studies were of moderate or high quality using the Methodological Index for Non-Randomized Studies tool.

CONCLUSIONS

Recurrent MASLD and MASH after liver transplant occur frequently, but adverse clinical outcomes due to disease recurrence are infrequent, maybe due to insufficient data on long-term follow-up. Long-term outcomes after transplantation for MASLD appear favorable; however, identifying those more likely to have progressive recurrent disease leading to adverse clinical outcomes may allow for pre- and posttransplant interventions to improve outcomes further.

Evolution of liver transplantation in the metabolic dysfunction-associated steatotic liver disease era: Tracking impact through time

Liver transplantation (LT) for metabolic dysfunction-associated steatotic liver disease (MASLD) is increasing globally due to rising rates of obesity and metabolic syndrome, posing significant challenges. MASLD patients typically present with advanced age, higher body mass index (BMI), and metabolic comorbidities such as diabetes, hypertension, and dyslipidemia. Comprehensive pre-transplant evaluations are crucial for assessing surgical risks and preparing patients for transplantation. MASLD patients with higher BMI may experience longer operative times, potentially affecting intraoperative outcomes. In the months following LT, MASLD recipients face persistent challenges, including a higher incidence of metabolic syndrome and cardiovascular events compared to non-MASLD recipients. However, survival rates at 1-, 3-, and 5-years post-LT do not markedly differ from other etiologies, indicating comparable surgical outcomes. Optimizing outcomes in MASLD patients undergoing LT demands a multidisciplinary approach from pre-transplant assessment to post-transplant care. Strategies must address metabolic comorbidities, manage cardiovascular health, and monitor steatosis recurrence, which can be exacerbated by obesity and diabetes. This approach aims to mitigate long-term graft complications and mortality risks, ultimately enhancing transplant success and patient well-being. Continued research is essential to refine these approaches and meet the evolving challenges posed by MASLD as a leading indication for LT worldwide.

Combination of risk alleles of PNPLA3, TM6SF2, and HSD17B13 of donors can predict recurrence of steatotic liver disease after liver transplantation

AIMS

This study aimed to identify the genetic risk factors from donors or recipients that contribute to postliver transplantation (LT) steatotic liver disease (SLD), focusing on the genetic risk score (GRS) based on single nucleotide polymorphisms (SNPs) in SLD patients.

METHODS

This retrospective study included 55 Japanese SLD recipients and their respective donors. Genotyping of PNPLA3, TM6SF2, and HSD17B13 was undertaken, and the combined GRS was calculated. The relationship between the GRS and the incidence of posttransplant SLD was also evaluated.

RESULTS

The SLD recipients had a high prevalence of post-LT graft steatosis/steatohepatitis (76.4% and 58.2%, respectively). Although the recipients had a high frequency of risk alleles, there was no relationship between the number of risk alleles for each SNP and the incidence of posttransplant SLD. In contrast, an increased number of risk alleles for any SNP in the donor was correlated with high incidence rates of both post-LT steatosis and steatohepatitis. A multivariable analysis showed that a high donor GRS was an independent risk factor for graft steatosis (odds ratio 8.77; 95% CI, 1.94-52.94; p = 0.009). Similarly, a high donor GRS was an independent risk factor (odds ratio 6.76; 95% CI, 1.84-30.78; p = 0.007) for post-LT graft steatohepatitis.

CONCLUSIONS

Donor risk alleles of PNPLA3, TM6SF2, and HSD17B13, rather than recipient risk alleles, have been implicated in the development of posttransplant SLD. The combination of these donor risk alleles into a GRS could predict the development of posttransplant SLD.

Metabolic-Dysfunction-Associated Steatotic Liver Disease (MASLD) after Liver Transplantation: A Narrative Review of an Emerging Issue

The development of steatotic liver disease after liver transplant (LT) is widely described, and epidemiological data have revealed an increased incidence in recent times. Its evolution runs from simple steatosis to steatohepatitis and, in a small proportion of patients, to significant fibrosis and cirrhosis. Apparently, post-LT steatotic disease has no impact on the recipient's overall survival; however, a higher cardiovascular and malignancy burden has been reported. Many donors' and recipients' risk factors have been associated with this occurrence, although the recipient-related ones seem of greater impact. Particularly, pre- and post-LT metabolic alterations are strictly associated with steatotic graft disease, sharing common pathophysiologic mechanisms that converge on insulin resistance. Other relevant risk factors include genetic variants, sex, age, baseline liver diseases, and immunosuppressive drugs. Diagnostic evaluation relies on liver biopsy, although non-invasive methods are being increasingly used to detect and monitor both steatosis and fibrosis stages. Management requires a multifaceted approach focusing on lifestyle modifications, the optimization of immunosuppressive therapy, and the management of metabolic complications. This review aims to synthesize the current knowledge of post-LT steatotic liver disease, focusing on the recent definition of metabolic-dysfunction-associated steatotic liver disease (MASLD) and its metabolic and multisystemic concerns.

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.

Utility and prognostic value of diagnosing MAFLD in patients undergoing liver transplantation for alcohol-related liver disease

BACKGROUND

Recently, the term metabolic dysfunction-associated fatty liver disease (MAFLD) was proposed to replace non-alcoholic fatty liver disease (NAFLD). This concept enables diagnosing liver disease associated with metabolic dysfunction in patients with alcohol-related liver disease (ALD), a main indication for liver transplantation (LTx). We assessed MAFLD prevalence in ALD patients undergoing LTx and its prognostic value on post-LTx outcomes.

METHODS

We retrospectively analyzed all ALD patients transplanted at our center between 1990 and August 2020. MAFLD was diagnosed based on the presence or history of hepatic steatosis and a BMI > 25 or type II diabetes or ≥ 2 metabolic risk abnormalities at LTx. Overall survival and risk factors for recurrent liver and cardiovascular events were analyzed by Cox regression.

RESULTS

Of the 371 included patients transplanted for ALD, 255 (68.7%) had concomitant MAFLD at LTx. Median follow-up post-LTx was 72 months (IQR: 34.50-122). Patients with ALD-MAFLD were older at LTx (p = .001), more often male (p < .001) and more frequently had hepatocellular carcinoma (p < .001). No differences in perioperative mortality and overall survival were found. ALD-MAFLD patients had an increased risk of recurrent hepatic steatosis, irrespective of alcohol relapse, but no superimposed risk of cardiovascular events.

CONCLUSIONS

The co-presence of MAFLD at LTx for ALD is associated with a distinct patient profile and is an independent risk factor for recurrent hepatic steatosis. The use of MAFLD criteria in ALD patients might increase awareness and treatment of specific hepatic and systemic metabolic abnormalities before and after LTx.

Clinical evidence of outcomes following liver transplantation in patients with nonalcoholic steatohepatitis: An updated meta-analysis and systematic review

OBJECTIVE

Nonalcoholic steatohepatitis (NASH) is a dramatically growing indication for liver transplantation (LT) worldwide and the posttransplant outcomes of NASH patients are currently under intensive investigation. This quantitative meta-analysis aimed to update the clinical evidence on outcomes of transplanted patients with NASH.

METHODS

We performed a systematic review and meta-analysis of studies (published up to September 15, 2021) that focused on LT outcomes for NASH versus non-NASH patients. Random-effect meta-analysis was conducted to calculate pooled odds ratios (ORs) and 95% confidence intervals (CIs). Subgroup analyses based on crucial baseline clinical characteristics and leave-one-out sensitivity analyses were conducted to assess the robustness of the pooled results. Meta-regression was used to evaluate study-level demographic, clinical, and biochemical characteristics to identify potential confounders affecting patient survival.

RESULTS

Twenty-two non-randomized comparative studies with 1,538 NASH and 6,014 non-NASH patients were included. 1- (OR, 0.94; 95% CI, 0.77-1.14), 3- (OR, 0.82; 95% CI, 1.00-1.22), and 5- (OR, 1.05; 95% CI, 0.84-1.31) year patient survival was equivalent between NASH and non-NASH recipients. NASH patients were associated with similar cardiovascular mortality (OR, 1.36; 95% CI, 0.89-2.09) and retransplantation rates (OR, 0.69; 95% CI, 1.03-1.53), lower graft failure-related mortality (OR, 0.11; 95% CI, 0.29-0.74), but higher sepsis-related mortality (OR, 1.53; 95% CI, 1.13-2.06). Meta-regression revealed that a higher proportion of patients with hepatocellular carcinoma (HCC) were associated with significantly superior overall patient survival at 1 (P = 0.044), 3 (P = 0.035) and 5 (P = 0.049) years after LT in NASH compared with non-NASH.

CONCLUSIONS

This study shows no difference in posttransplant survival between NASH and non-NASH patients. Carefully selected patients with NASH-related HCC may benefit from LT. NASH recipients should be managed with caution posttransplant, especially regarding the potentially high risk of sepsis-related death.

Morbid obesity increases death and dropout from the liver transplantation waiting list: A prospective cohort study

Liver transplant (LT) candidates with a body mass index (BMI) over 40 kg/m2 have lower access to a liver graft without clear explanation. Thus, we studied the impact of obesity on the waiting list (WL) and aimed to explore graft proposals and refusal.

METHOD

Data between January 2007 and December 2017 were extracted from the French prospective national database: CRISTAL. Competing risk analyses were performed to evaluate predictors of receiving LT. Competitive events were (1) death/WL removal for disease aggravation or (2) improvement. The link between grade obesity, grafts propositions, and reason for refusal was studied.

RESULTS

15,184 patients were analysed: 10,813 transplant, 2847 death/dropout for aggravation, 748 redirected for improvement, and 776 censored. Mortality/dropout were higher in BMI over 35 (18% vs. 14% 1 year after listing) than in other candidates. In multivariate analysis, BMI>35, age, hepatic encephalopathy, and ascites were independent predictors of death/dropout. Candidates with a BMI ≥ 35 kg/m2 had reduced access to LT, without differences in graft proposals. However, grafts refusal was more frequent especially for 'morphological incompatibility' (14.9% vs. 12.7% p < 0.01).

CONCLUSION

BMI over 35 kg/m2 reduces access to LT with increased risk of dropout and mortality. Increased mortality and dropout could be due to a lower access to liver graft secondary to increased graft refusal for morphological incompatibility.