Prospective Study of Outcomes in Adults with Nonalcoholic Fatty Liver Disease

Pre-emptive TIPSS in Acute Variceal Bleeding: Current Status, Controversies, and Future Directions

Acute variceal bleeding (AVB) is associated with significant short-term morbidity and mortality. Pre-emptive transjugular intrahepatic portosystemic shunt (p-TIPSS) is recommended to prevent rebleeding in AVB patients with a high risk of rebleeding. Despite the benefit of preventing rebleeding and de-novo ascites, the uptake of p-TIPSS remains low because logistic challenges in the real-world setting. In this review, we summarize the current evidence and controversies on p-TIPSS including patient selection for p-TIPSS, particularly in the setting of NASH cirrhosis and acute-on-chronic liver failure, the role of sarcopenia, renal impairment in the setting of p-TIPSS. Finally, we summarize both pharmacological and nonpharmacological strategies to optimize outcomes in patients undergoing p-TIPSS.

Hepatocyte Smoothened Activity Controls Susceptibility to Insulin Resistance and Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS

Nonalcoholic steatohepatitis (NASH), a leading cause of cirrhosis, strongly associates with the metabolic syndrome, an insulin-resistant proinflammatory state that disrupts energy balance and promotes progressive liver degeneration. We aimed to define the role of Smoothened (Smo), an obligatory component of the Hedgehog signaling pathway, in controlling hepatocyte metabolic homeostasis and, thereby, susceptibility to NASH.

METHODS

We conditionally deleted Smo in hepatocytes of healthy chow-fed mice and performed metabolic phenotyping, coupled with single-cell RNA sequencing (RNA-seq), to characterize the role of hepatocyte Smo in regulating basal hepatic and systemic metabolic homeostasis. Liver RNA-seq datasets from 2 large human cohorts were also analyzed to define the relationship between Smo and NASH susceptibility in people.

RESULTS

Hepatocyte Smo deletion inhibited the Hedgehog pathway and promoted fatty liver, hyperinsulinemia, and insulin resistance. We identified a plausible mechanism whereby inactivation of Smo stimulated the mTORC1-SREBP1c signaling axis, which promoted lipogenesis while inhibiting the hepatic insulin cascade. Transcriptomics of bulk and single Smo-deficient hepatocytes supported suppression of insulin signaling and also revealed molecular abnormalities associated with oxidative stress and mitochondrial dysfunction. Analysis of human bulk RNA-seq data revealed that Smo expression was (1) highest in healthy livers, (2) lower in livers with NASH than in those with simple steatosis, (3) negatively correlated with markers of insulin resistance and liver injury, and (4) declined progressively as fibrosis severity worsened.

CONCLUSIONS

The Hedgehog pathway controls insulin sensitivity and energy homeostasis in adult livers. Loss of hepatocyte Hedgehog activity induces hepatic and systemic metabolic stress and enhances susceptibility to NASH by promoting hepatic lipoxicity and insulin resistance.

Trimethylamine N-Oxide Levels in Non-Alcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis

Non-alcoholic fatty liver disease (NAFLD) represents an entity with an increasing prevalence which is characterized by significant hepatic and extrahepatic complications. Its pathophysiology is multifactorial, with gut dysbiosis being considered a major determinant. In this systematic review and meta-analysis, we tried to evaluate the association between the major gut microbial metabolite trimethylamine N-oxide (TMAO) and NAFLD. We performed a literature search for studies that determined circulating TMAO in patients with and without NAFLD. The database search identified 136 studies, and upon application of the exclusion criteria, 7 studies with 7583 individuals (NAFLD 2923, control 4660) were ultimately included in the meta-analysis. Compared to the control group, NAFLD patients had significantly higher circulating TMAO (SMD: 0.66, 95% CI -0.12 to 1.21, p = 0.02, I²: 94%). The results remained unaffected after the exclusion of one influential study. The subgroup analysis revealed significantly higher TMAO in individuals with histologically proven NAFLD and in studies measuring TMAO with high-performance liquid chromatography. No differences were observed according to the study design or study region. However, funnel plot asymmetry was observed, indicating publication bias. In conclusion, patients with NAFLD had increased levels of TMAO, a hazardous gut microbial metabolite, suggesting its important role in the gut-liver interaction.

The role of noninvasive scoring systems for predicting cardiovascular disease risk in patients with nonalcoholic fatty liver disease: a systematic review and meta-analysis

BACKGROUNDS

Cardiovascular disease (CVD) is suggested as a leading cause of death among patients with nonalcoholic fatty liver disease (NAFLD). The aim of this work was to clarify the role of noninvasive scoring systems (NSSs) in predicting CVD risk among this population.

METHODS

The PubMed, Web of Science, and Cochrane databases were searched until 23 March 2022. Meta-analysis was performed for three most commonly used NSS separately, that is, fibrosis-4 index (FIB-4), NAFLD fibrosis score (NFS), and AST/platelet ratio index (APRI).

RESULTS

Totally, nine studies including 155 382 patients with NAFLD were enrolled. Patients with NAFLD had a higher risk of CVD with increasing FIB-4 score (1.94, 1.52-2.46), the association remained significant after adjustment for age, sex, body mass index, hypertension, and diabetes (2.44, 1.85-3.22). Similarly, a higher risk of CVD was also observed in patients with increasing NFS (2.17, 1.58-2.98) and APRI scores (1.36, 1.04-1.79) in the unadjusted model. However, in the adjusted model, the association was significant only for NFS (3.83, 1.40-10.43), but not for APRI (1.41, 0.79-2.51). Additionally, the increment in CVD risk was most noticeable in subgroup of FIB > 2.67 vs. FIB ≤ 1.3 (6.52, 3.07-13.86) and subgroup of NFS > 0.676 vs. NFS ≤ -1.455 (16.88, 5.68-50.23). All subgroup analyses showed significant associations between FIB-4, NFS, and risk of CVD. Sensitivity analyses did not modify these results.

CONCLUSIONS

FIB-4 and NFS might be useful in identifying those who are at higher risk of CVD among patients with NAFLD. However, APRI was not recommended for this use.

Age-dependent effects of diabetes and obesity on liver-related events in non-alcoholic fatty liver disease: Subanalysis of CLIONE in Asia

BACKGROUND AND AIM

Older age, type 2 diabetes mellitus (T2DM), and obesity are known risk factors for liver-related events (LREs). We investigated the impacts of T2DM and obesity on LRE according to age in Japanese patients with non-alcoholic fatty liver disease (NAFLD).

METHODS

We performed a subanalysis of a retrospective cohort study (CLIONE in Asia), including 1395 patients with biopsy-proven NAFLD. The median follow-up was 4.6 years.

RESULTS

The median age was 57 years, and 36.2% had T2DM. The median body mass index (BMI) was 27.4, and 28.5% were severely obese (BMI ≥ 30). During follow-up, 37 patients developed hepatocellular carcinoma (HCC), and 58 patients developed LRE. In patients younger than 65 years, advanced fibrosis (hazard ratio [HR] 7.69, P < 0.001) and T2DM (HR 3.37, P = 0.017) were HCC risk factors, and advanced fibrosis (HR 9.40, P < 0.001) and T2DM (HR 2.51, P = 0.016) were LRE risk factors. In patients 65 years and older, advanced fibrosis (HR 4.24, P = 0.010) and obesity (HR 4.60, P = 0.006) were HCC risk factors, and advanced fibrosis (HR 4.22, P = 0.002) and obesity (HR 4.22, P = 0.002) were LRE risk factors.

CONCLUSION

Type 2 diabetes mellitus and obesity contributed to LRE in younger and older patients, respectively, along with advanced fibrosis. Therefore, controlling T2DM in patients younger than 65 years and controlling weight in patients 65 years and older could prevent LRE. The development of age-dependent screening and management strategies is necessary for patients with NAFLD.

Serum levels of immunoglobulin M-free inhibitors of macrophage/CD5L as a predictive and early diagnostic marker for nonalcoholic steatohepatitis-associated hepatocellular carcinoma

BACKGROUND

The apoptosis inhibitor of macrophage (AIM) is usually associated with the immunoglobulin M (IgM) pentamer in the blood and is dissociated from IgM in various diseases, including hepatocellular carcinoma (HCC) in nonalcoholic steatohepatitis (NASH). We aimed to elucidate whether IgM-free AIM (fAIM) is useful for detecting latent HCC in NASH.

METHODS

This research consisted of two cohort studies. The levels of serum fAIM, alpha-fetoprotein (AFP), and des-gamma carboxy prothrombin (DCP) of 18 NASH patients who developed HCC were measured during the follow-up period before HCC diagnosis (median, 4.7 years). In total, 199 patients with nonalcoholic fatty liver disease (NAFLD) were included in the HCC survey. The serum fAIM levels were analyzed using enzyme-linked immunosorbent assays.

RESULTS

In the cohort of 18 patients with HCC, 12 had high fAIM at the time of the initial blood sample, three had normal fAIM levels throughout the follow-up period, and three had fAIM elevated from normal to positive. The positive ratio of fAIM prior to HCC diagnosis remained significantly higher than that of AFP and DCP, and the fAIM ratio gradually increased. In a survey of 199 non-HCC NAFLD patients, a Cox regression analysis using independent variables, such as AFP, fAIM, age, albumin, bilirubin, and fibrosis stage, revealed that fAIM and AFP were significantly associated with the incidence of HCC.

CONCLUSIONS

During the development of NASH-HCC, AIM activation in blood appears to start even before HCC is diagnostically detectable. Thus, the serum IgM-free AIM levels could be a new, sensitive biomarker for latent NASH-HCC.

An international survey on patterns of practice in NAFLD and expectations for therapies-The POP-NEXT project

BACKGROUND AND AIMS

Differences between countries in NAFLD patient care pathways and management need to be understood prior to defining supranational guidelines.

APPROACH AND RESULTS

We conducted an anonymous survey in France, Germany, Hong Kong, Italy, Romania, Spain, the United Kingdom, and the United States among physicians providing specialist care for patients with NAFLD. Modalities of patient referral, patterns of practice (diagnosis, staging, monitoring, and indications for liver biopsy), therapeutic management, and expectations for future NASH pharmacotherapies were assessed, with 664 physicians completing the survey. Referral to surveyed physicians (SPs) mostly came from primary care. Prior to referral, NAFLD was rarely diagnosed, and noninvasive tests were not performed. Screening for comorbidities by SPs was incomplete and cardiovascular risk not calculated. Elastometry in combination with a serum biomarker was the most common first-line method for fibrosis staging. Liver biopsy, when performed, was often delayed by at least 1 year after diagnosis. It was, however, recommended even if noninvasive methods indicated advanced fibrosis. Frequent, biannual monitoring was conducted, including HCC surveillance in Stage 3 fibrosis. SPs rarely implemented and followed dietary and lifestyle changes themselves, and local availability of such programs was highly heterogenous. SPs favored pharmacotherapy based on mechanism of action adapted to the stage of the disease, including for early stages such as steatohepatitis with mild fibrosis.

CONCLUSIONS

This international survey revealed major deficiencies and delays in referral pathways, suboptimal screening for comorbidities or managing of lifestyle modifications by SPs, and limited local availability for nonpharmacological interventions. Monitoring practices are not aligned with current guidelines.

Non-alcoholic fatty liver disease screening in type 2 diabetes mellitus: A cost-effectiveness and price threshold analysis

Introduction: The cost-effectiveness of screening asymptomatic non-alcoholic fatty liver disease (NAFLD) patients remains debatable, with current studies assuming lifelong benefits of NAFLD screening while neglecting cardiovascular outcomes. This study aims to assess the cost-effectiveness of NAFLD screening among type 2 diabetes mellitus (T2DM) patients, and to establish a price threshold for NAFLD treatment, when it becomes available. Method: A Markov model was constructed comparing 4 screening strategies (versus no screening) to identify NAFLD with advanced fibrosis among T2DM patients: fibrosis-4 (FIB-4), vibration-controlled transient elastography (VCTE), FIB-4 and VCTE (simultaneous), and FIB-4 and VCTE (sequential). Sensitivity analyses and price threshold analyses were performed to assess parameter uncertainties in the results. Results: VCTE was the most cost-effective NAFLD screening strategy (USD24,727/quality-adjusted life year [QALY]), followed by FIB-4 (USD36,800/QALY), when compared to no screening. Probabilistic sensitivity analysis revealed a higher degree of certainty for VCTE as a cost-effective strategy compared to FIB-4 (90.7% versus 73.2%). The duration of expected screening benefit is the most influential variable based on incremental cost-effectiveness ratio tornado analysis. The minimum duration of screening benefit for NAFLD screening to be cost-effective was at least 2.6 years. The annual cost of NAFLD treatment should be less than USD751 for NAFLD screening to be cost-effective. Conclusion: Both VCTE and FIB-4 are cost-effective NAFLD screening strategies among T2DM patients in Singapore. However, given the lack of access to VCTE at primacy care and potential budget constraints, FIB-4 can also be considered for NAFLD screening among T2DM patients in Singapore. Keywords: Cost-effectiveness analysis, fatty liver, screening, liver fibrosis, population health

CD47-SIRPα axis blockade in NASH promotes necroptotic hepatocyte clearance by liver macrophages and decreases hepatic fibrosis

Necroptosis contributes to hepatocyte death in nonalcoholic steatohepatitis (NASH), but the fate and roles of necroptotic hepatocytes (necHCs) in NASH remain unknown. We show here that the accumulation of necHCs in human and mouse NASH liver is associated with an up-regulation of the "don't-eat-me" ligand CD47 on necHCs, but not on apoptotic hepatocytes, and an increase in the CD47 receptor SIRPα on liver macrophages, consistent with impaired macrophage-mediated clearance of necHCs. In vitro, necHC clearance by primary liver macrophages was enhanced by treatment with either anti-CD47 or anti-SIRPα. In a proof-of-concept mouse model of inducible hepatocyte necroptosis, anti-CD47 antibody treatment increased necHC uptake by liver macrophages and inhibited markers of hepatic stellate cell (HSC) activation, which is responsible for liver fibrogenesis. Treatment of two mouse models of diet-induced NASH with anti-CD47, anti-SIRPα, or AAV8-H1-shCD47 to silence CD47 in hepatocytes increased the uptake of necHC by liver macrophages and decreased markers of HSC activation and liver fibrosis. Anti-SIRPα treatment avoided the adverse effect of anemia found in anti-CD47-treated mice. These findings provide evidence that impaired clearance of necHCs by liver macrophages due to CD47-SIRPα up-regulation contributes to fibrotic NASH, and suggest therapeutic blockade of the CD47-SIRPα axis as a strategy to decrease the accumulation of necHCs in NASH liver and dampen the progression of hepatic fibrosis.

Disulfiram ameliorates nonalcoholic steatohepatitis by modulating the gut microbiota and bile acid metabolism

Nonalcoholic steatohepatitis (NASH) has been linked with the gut-liver axis. Here, we investigate the potential for repurposing disulfiram (DSF), a drug commonly used to treat chronic alcoholism, for NASH. Using a mouse model, we show that DSF ameliorates NASH in a gut microbiota-dependent manner. DSF modulates the gut microbiota and directly inhibits the growth of Clostridium. Administration of Clostridium abolishes the ameliorating effects of DSF on NASH. Mechanistically, DSF reduces Clostridium-mediated 7α-dehydroxylation activity to suppress secondary bile acid biosynthesis, which in turn activates hepatic farnesoid X receptor signaling to ameliorate NASH. To assess the effect of DSF on human gut microbiota, we performed a self-controlled clinical trial (ChiCTR2100048035), including 23 healthy volunteers who received 250 mg-qd DSF for 7 days. The primary objective outcomes were to assess the effects of the intervention on the diversity, composition and functional profile of gut microbiota. The pilot study shows that DSF also reduces Clostridium-mediated 7α-dehydroxylation activity. All volunteers tolerated DSF well and there were no serious adverse events in the 7-day follow-up period. Transferring fecal microbiota obtained from DSF-treated humans into germ-free mice ameliorates NASH. Collectively, the observations of similar ameliorating effects of DSF on mice and humans suggest that DSF ameliorates NASH by modulating the gut microbiota and bile acid metabolism.

Exosomal microRNAs and Progression of Nonalcoholic Steatohepatitis (NASH)

Nonalcoholic fatty liver disease (NAFLD)/metabolic associated fatty liver disease (MAFLD) is becoming a public health problem worldwide. Steatosis as the simple form and nonalcoholic steatohepatitis (NASH) as its progression form are commonly seen in liver biopsy specimens from patients with obesity, diabetes, hyperlipidemia, hypertension, and the use of certain drugs. Patients with NASH and advanced fibrosis were associated with increased risks of liver-related complications, including hepatocellular carcinoma (HCC). However, the mechanisms regarding the progression from simple steatosis to NASH fibrosis remain incompletely understood. Because NASH-caused liver injury is a complex process and multiple cell types are involved, intercellular communication is likely mediated by extracellular vesicles. Exosomes are a type of small extracellular vesicles and contain various cellular molecules, including proteins, messenger RNAs (mRNAs), and microRNAs (miRNAs). MiRNAs are short, non-coding RNA species that are important post-transcriptional regulators of gene expression and may play an important role in the pathogenesis of NALFD/NASH. In this article, we review the articles about NASH and exosomal miRNAs published in the most recent English literature through PubMed search and discuss the most recent criteria for histological diagnosis, pathogenesis from steatosis to NASH, roles of exosomal miRNAs in NASH pathogenesis and progression, as well as their potential in future clinical diagnosis and treatment for patients with NASH.

Incidence of, Risk Factors for, and Outcomes After Ascites in a Population-Based Cohort of Older Americans

BACKGROUND

The incidence of, risk factors for, and outcomes after the development of ascites are poorly described for contemporary patients with cirrhosis.

METHODS

We examined data for a 20% random sample of US Medicare enrollees with cirrhosis and Part D prescription coverage from 2008 to 2019, excluding patients with heart failure and diuretic use prior to cirrhosis. Among 63,364 persons with cirrhosis, we evaluated the incidence of ascites using an Aalen-Johansen estimator. We evaluated risk factors for ascites, mortality, and mortality after ascites using multistate modeling. We determined the associations with each outcome for an array of medication exposures including nonselective beta-blockers, antiviral therapy, statins, rifaximin, anticoagulants, and metformin.

RESULTS

The cumulative incidence of ascites was 5.1%, 9.5%, and 10.7% and 1, 3, and 5 years overall. The corresponding data for ascites requiring paracentesis were 1%, 2.1%, and 2.4%. Persons aged < 65 years, with alcohol-related cirrhosis, varices, or HE, are most likely to develop ascites. The risk of ascites was higher for persons taking any NSBB (including carvedilol) but lower for those taking atorvastatin (but not other statins) and antiviral therapy for Hepatitis C. Incident ascites was associated with increased risk of death, HR 27.6 95%CI(21.7-35.1). Survival following ascites was 1.08 years (interquartile range, IQR, 0.26-2.75), 0.38 years (IQR0.1-1.3) for those requiring paracentesis. Lipophilic statins were the only medications associated with lower mortality after ascites requiring paracentesis.

CONCLUSIONS

Ascites is associated with a high risk of death. Very few candidate therapies are associated with the reduction in the risk of ascites and mortality after ascites development.

Hepatocellular Carcinoma Chemoprevention with Generic Agents

Liver cancer, mainly hepatocellular carcinoma (HCC), remains a major cause of cancer-related death worldwide. With the global epidemic of obesity, the major HCC etiologies have been dynamically shifting from viral to metabolic liver diseases. This change has made HCC prevention difficult with increasingly elusive at-risk populations as rational target for preventive interventions. Besides ongoing efforts to reduce obesity and metabolic disorders, chemoprevention in patients who already have metabolic liver diseases may have a significant impact on the poor HCC prognosis. Hepatitis B- and hepatitis C-related HCC incidences have been substantially reduced by the new antivirals, but HCC risk can persist over a decade even after successful viral treatment, highlighting the need for HCC-preventive measures also in these patients. Experimental and retrospective studies have suggested potential utility of generic agents such as lipophilic statins and aspirin for HCC chemoprevention given their well-characterized safety profile, although anticipated efficacy may be modest. In this review, we overview recent clinical and translational studies of generic agents in the context of HCC chemoprevention under the contemporary HCC etiologies. We also discuss newly emerging approaches to overcome the challenges in clinical testing of the agents to facilitate their clinical translation.

Risk of advanced fibrosis in first-degree relatives of patients with nonalcoholic fatty liver disease

BACKGROUNDA pilot, single-center study showed that first-degree relatives of probands with nonalcoholic fatty liver disease (NAFLD) cirrhosis have a high risk of advanced fibrosis. We aimed to validate these findings using 2 independent cohorts from the US and Europe.METHODSThis prospective study included probands with NAFLD with advanced fibrosis, NAFLD without advanced fibrosis, and non-NAFLD, with at least 1 first-degree relative. A total of 396 first-degree relatives - 220 in a derivation cohort and 176 in a validation cohort - were enrolled in the study, and liver fibrosis was evaluated using magnetic resonance elastography and other noninvasive imaging modalities. The primary outcome was prevalence of advanced fibrosis in first-degree relatives.RESULTSPrevalence of advanced fibrosis in first-degree relatives of probands with NAFLD with advanced fibrosis, NAFLD without advanced fibrosis, and non-NAFLD was 15.6%, 5.9%, and 1.3%, respectively (P = 0.002), in the derivation cohort, and 14.0%, 2.6%, and 1.3%, respectively (P = 0.004), in the validation cohort. In multivariable-adjusted logistic regression models, age of ≥50 years (adjusted OR [aOR]: 2.63, 95% CI 1.0-6.7), male sex (aOR: 3.79, 95% CI 1.6-9.2), diabetes mellitus (aOR: 3.37, 95% CI 1.3-9), and a first-degree relative with NAFLD with advanced fibrosis (aOR: 11.8, 95% CI 2.5-57) were significant predictors of presence of advanced fibrosis (all P < 0.05).CONCLUSIONFirst-degree relatives of probands with NAFLD with advanced fibrosis have significantly increased risk of advanced fibrosis. Routine screening should be done in the first-degree relatives of patients with advanced fibrosis.FUNDINGSupported by NCATS (5UL1TR001442), NIDDK (U01DK061734, U01DK130190, R01DK106419, R01DK121378, R01DK124318, P30DK120515, K23DK119460), NHLBI (P01HL147835), and NIAAA (U01AA029019); Academy of Finland grant 309263; the Novo Nordisk, EVO, and Sigrid Jusélius Foundations; and the Innovative Medicines Initiative 2 Joint Undertaking under grant agreement 777377. This Joint Undertaking receives support from the European Union's Horizon 2020 research and innovation program and the EFPIA.

High frequency of acute decompensation and cancer in patients with compensated cirrhosis due to nonalcoholic fatty liver disease: A retrospective cohort study

The natural history of compensated cirrhosis due to nonalcoholic fatty liver disease (NAFLD) has not been completely characterized. The aim of the present study was to assess the incidence and risk factors of acute decompensation of cirrhosis, hepatocellular carcinoma, and extrahepatic cancers. This was a multicenter, retrospective, cohort study including 449 patients with compensated cirrhosis due to NAFLD. We calculated cumulative incidences and used competitive risk analysis to determine the risk factors associated with decompensation and cancer development. Over a median of 39 months of follow-up, 124 patients (28%) presented acute decompensation. The most frequent decompensation was ascites (21%) followed by hepatic encephalopathy (15%), variceal bleeding (9%), and spontaneous bacterial peritonitis (3%). Acute-on-chronic liver failure was diagnosed in 6% of patients during follow-up. Liver function parameters and specifically an albumin level below 40 g/L were independently associated with an increased risk of decompensation. The presence of ischemic heart disease was independently associated with acute decompensation. Seventy-eight patients (18%) developed hepatocellular carcinoma or extrahepatic cancers during follow-up (51 and 27, respectively). Conclusion: Patients with compensated cirrhosis due to NAFLD are at high risk of severe liver complications, such as the development of acute decompensation, in a relative short follow-up time. This population is at high risk of hepatic and extrahepatic cancers.

Racial/ethnic differences in fibrosis prevalence and progression in biopsy-proven steatosis: A focus on the Asian American population

Fatty liver disease (FLD) is a leading cause of chronic liver disease (CLD) globally, and vulnerable populations are disproportionately affected. Prior studies have suggested racial/ethnic differences in FLD prevalence and severity; however, these studies often excluded Asian Americans. This study aims to evaluate racial/ethnic differences in the prevalence of, and predictors associated with steatohepatitis, advanced fibrosis, and fibrosis progression over time within a diverse population. Using descriptive analyses and multivariable modeling, we performed a longitudinal evaluation of 648 patients with histologic evidence of FLD (steatosis or steatohepatitis) from August 2009 to February 2020 within San Francisco's safety-net health care system. Overall demographics were median age of 53 years, 54% male, and 38% Asian (40% Hispanic, 14% White). On histology, 61% had steatohepatitis and 30% had advanced fibrosis (≥F3). The comparison between steatosis and steatohepatitis groups showed differences in sex, race/ethnicity, metabolic risk factors, and co-existing CLD (predominantly viral hepatitis); patients with steatosis were more likely to be Asian (50%), and those with steatohepatitis were more likely to be Hispanic (51%). On multivariable modeling, while Asian race (vs. non-Asian) was not associated with steatohepatitis or advanced fibrosis when models included all relevant clinical predictors, Asian race was associated with higher relative risk of fibrosis progression as defined by change in Fibrosis-4 category over time (relative risk ratio = 1.9; p = 0.047). Conclusion: In this vulnerable population with a large proportion of Asian Americans, Asian race was associated with progression of fibrosis. Given the relative paucity of data in this high-risk group, future studies should confirm these findings.

Recent guidelines for Non-Alcoholic Fatty Liver disease (NAFLD)/ Fatty Liver Disease (FLD): Are they already outdated and in need of supplementation?

Non-Alcoholic Fatty Liver Disease (NAFLD) is a highly prevalent disease and unmet clinical need that we have recently proposed to be renamed for simplicity and accuracy as Fatty Liver Disease (FLD), with specific subclassifications. It has been commonly associated with metabolic comorbidities, including obesity, type 2 diabetes (T2D), hypertension, and hyperlipidemia. Since no Federal and Drug Administration (FDA) approved treatments exist to date, recent guidelines recommend lifestyle interventions, bariatric surgery, and pharmacotherapy, i.e. glucagon-like peptide-1 receptor agonists (GLP-1RA), peroxisome proliferator-activated receptor-γ (PPAR-γ) agonists, and SGLT-2 inhibitors for its treatment. A new and novel medication for the treatment of T2D, tirzepatide, a dual GIP/GLP-1RA, was approved by the FDA only one week after guidelines were published, and ongoing clinical trials demonstrate promising results not only for T2D but also for body weight and steatosis. Moreover, we realize that distinct subgroups exist under the umbrella of FLD and, thus, more precise therapeutic recommendations would be needed towards the goal of personalized medicine and therapeutics for these subgroups. As the metabolism field is moving forward very fast and as several molecules in development will most likely demonstrate benefits in NAFLD treatment in the foreseeable future, guidelines will need to be frequently updated. This rapid pace of change prompts us to propose that guidelines should exist as living online documents on the websites of professional societies, so that they continue being updated following and reflecting the rapid progress in this and other fields of medicine.

NAFLD in Cardiovascular Diseases: A Contributor or Comorbidity?

Nonalcoholic fatty liver disease (NAFLD) and cardiovascular diseases are both highly prevalent conditions around the world, and emerging data have shown an association between them. This review found several longitudinal and cross-sectional studies showing that NAFLD was associated with coronary artery disease, cardiac remodeling, aortic valve remodeling, mitral annulus valve calcifications, diabetic cardiomyopathy, diastolic cardiac dysfunction, arrhythmias, and stroke. Although the specific underlying mechanisms are not clear, many hypotheses have been suggested, including that metabolic syndrome might act as an upstream metabolic defect, leading to end-organ manifestations in both the heart and liver. Management of NAFLD includes weight loss through lifestyle interventions or bariatric surgery, and pharmacological interventions, often targeting comorbidities. Although there are no Food and Drug Administration-approved nonalcoholic steatohepatitis-specific therapies, several drug candidates have demonstrated effect in the improvement in fibrosis or nonalcoholic steatohepatitis resolution. Further studies are needed to assess the effect of those interventions on cardiovascular outcomes, the major cause of mortality in patients with NAFLD. In conclusion, a more comprehensive, multidisciplinary approach to diagnosis and management of patients with NAFLD and cardiovascular diseases is needed to optimize clinical outcomes.

Impact of the COVID-19 pandemic on the care and outcomes of people with NAFLD-related cirrhosis

Background & Aims

The COVID-19 pandemic has had a major negative impact on health systems and many chronic diseases globally. We aimed to evaluate the impact of the first year of the pandemic on the outcomes of people with NAFLD cirrhosis.

Methods

We conducted a before-after study in four University hospitals in Catalonia, Spain. Study subperiods were divided into Pre-pandemic (March/2019–February/2020) vs. Pandemic (March/2020–February/2021). The primary outcome was the rate of first liver-related event (LRE). Overall clinical outcomes (LREs plus cardiovascular plus all-cause mortality) were also assessed.

Results

A total of 354 patients were included, all of whom were compensated at the beginning of the study period; 83 individuals (23.5%) had a history of prior hepatic decompensation. Mean age was 67.3 years and 48.3% were female. Median BMI was 31.2 kg/m² and type 2 diabetes was present in 72.8% of patients. The rates of first LRE in the Pre-pandemic and Pandemic periods were 7.4% and 11.3% (p = 0.12), respectively. Whilst the rate of overall events was significantly higher in the Pandemic period (9.9% vs. 17.8%; p = 0.009), this was strongly associated with COVID-19-related deaths. The rate of worsened metabolic status was significantly higher in the Pandemic period (38.4% vs. 46.1%; p = 0.041), yet this was not associated with the risk of first LRE during the Pandemic period, whereas type 2 diabetes (odds ratio [OR] 3.77; 95% CI 1.15–12.32; p = 0.028), albumin <4 g/L (OR 4.43; 95% CI 1.76–11.17; p = 0.002) and Fibrosis-4 score >2.67 (OR 15.74; 95% CI 2.01–123.22; p = 0.009) were identified as risk factors in the multivariable analysis.

Conclusion

Overall, people with NAFLD cirrhosis did not present poorer liver-related outcomes during the first year of the pandemic. Health system preparedness seems key to ensure that people with NAFLD cirrhosis receive appropriate care during health crises.

Lay summary

Mobility restrictions and social stress induced by the COVID-19 pandemic have led to increased alcohol drinking and worsened metabolic control (e.g., weight gain, poor control of diabetes) in a large proportion of the population in many countries. We aimed to analyze whether people with cirrhosis due to non-alcoholic fatty liver disease, who are particularly vulnerable to such lifestyle modifications, were significantly impacted during the first year of the pandemic. We compared the clinical situation of 354 patients one year before the pandemic and one year after. We found that although metabolic control was indeed worse after the first year of the pandemic and patients presented worse clinical outcomes, the latter was mostly due to non-liver causes, namely COVID-19 itself. Moreover, the care provided to these patients did not worsen during the first year of the pandemic.

•

Patients with NAFLD cirrhosis did not present a higher rate of liver-related events during the COVID-19 pandemic.

•

Usual predictors, such as diabetes, albumin and FIB-4 were associated with higher risk of a first liver event.

•

Health system preparedness seems key to ensure patients with NAFLD cirrhosis receive appropriate care during health crises.

PNPLA3 rs738409 and risk of fibrosis in NAFLD: Exploring mediation pathways through intermediate histological features

BACKGROUND AND AIMS

It is unclear whether rs738409 (p.I148M) missense variant in patatin-like phospholipase domain-containing 3 rs738409 promotes fibrosis development by triggering specific fibrogenic pathways or by creating an unfavorable microenvironment by promoting steatosis, inflammation, and ultimately fibrosis. We tested the hypothesis that intermediate histologic traits, including steatosis, lobular and portal inflammation, and ballooning may determine the effect of rs738409 on liver fibrosis among individuals with biopsy-proven NAFLD.

APPROACH AND RESULTS

Causal mediation models including multiple mediators in parallel or sequentially were performed to examine the effect of rs738409, by decomposing its total effect on fibrosis severity into direct and indirect effects, mediated by histology traits in 1153 non-Hispanic White patients. Total effect of rs738409 on fibrosis was β = 0.19 (95% CI: 0.09-0.29). The direct effect of rs738409 on fibrosis after removing mediators' effects was β = 0.09 (95% CI: 0.01-0.17) and the indirect effect of rs738409 on fibrosis through all mediators' effects were β = 0.010 (95% CI: 0.04-0.15). Among all mediators, the greatest estimated effect size was displayed by portal inflammation (β = 0.09, 95% CI: 0.05-0.12). Among different sequential combinations of histology traits, the path including lobular inflammation followed by ballooning degeneration displayed the most significant indirect effect (β = 0.023, 95% CI: 0.011-0.037). Mediation analysis in a separate group of 404 individuals with biopsy-proven NAFLD from other races and ethnicity showed similar results.

CONCLUSIONS

In NAFLD, nearly half of the total effect of the rs738409 G allele on fibrosis severity could be explained by a direct pathway, suggesting that rs738409 may promote fibrosis development by activating specific fibrogenic pathways. A large proportion of the indirect effect of rs738409 on fibrosis severity is mediated through portal inflammation.

Clinical course of non-alcoholic fatty liver disease and the implications for clinical trial design

BACKGROUND & AIMS

The predicted risk and timeline to progression to liver-related outcomes in the population with NAFLD are not well-characterized. We aimed to examine the risk and time to progression to cirrhosis, hepatic decompensation and death in a contemporary population over a long follow-up period, to obtain information to guide endpoint selection and sample size calculations for clinical trials on NAFLD-related cirrhosis.

METHODS

This is a retrospective study of prospectively collected data in a medical record linkage system, including all adults diagnosed with NAFLD between 1996-2016 by clinical, biochemical and radiological criteria in Olmsted County, Minnesota and followed until 2019. Liver-related outcomes and death were ascertained and validated by individual medical record review. Time and risk of progression from NAFLD to cirrhosis to decompensation and death were assessed using multistate modeling.

RESULTS

A total of 5,123 individuals with NAFLD (median age 52 years, 53% women) were followed for a median of 6.4 (range 1-23) years. The risk of progression was as follows: from NAFLD to cirrhosis: 3% in 15 years; compensated cirrhosis to first decompensation: 33% in 4 years (8%/year); first decompensation to ≥2 decompensations: 48% in 2 years. Albumin, bilirubin, non-bleeding esophageal varices and diabetes were independent predictors of decompensation. Among the 575 deaths, 6% were liver related. Therapeutic trials in compensated cirrhosis would require enrolment of a minimum of 2,886 individuals followed for >2 years to detect at least a 15% relative decrease in liver-related endpoints.

CONCLUSION

In this population-based cohort with 23 years of longitudinal follow-up, NAFLD was slowly progressive, with liver-related outcomes affecting only a small proportion of people. Large sample sizes and long follow-up are required to detect reductions in liver-related endpoints in clinical trials.

LAY SUMMARY

For patients with compensated non-alcoholic steatohepatitis-related cirrhosis, the time spent in this state and the risk of progression to decompensation are not well-known in the population. We examined the clinical course of a large population-based cohort over 23 years of follow-up. We identified that adults with compensated cirrhosis spend a mean time of 4 years in this state and have a 10% per year risk of progression to decompensation or death. The risk of further progression is 3-fold higher in adults with cirrhosis and one decompensating event. These results are reflective of placebo arm risks in drug clinical trials and are essential in the estimation of adequate sample sizes.

Fatty liver index as a predictor for incident type 2 diabetes in community-dwelling adults: longitudinal findings over 12 years

BACKGROUND

Diagnosing fatty liver and identifying disease status are important for fatty liver related-diseases prevention. The fatty liver index (FLI), which can be easily available in clinical practice, can be very useful for managing fatty liver and preventing related diseases. No large-scale and long-term follow-up prospective studies have investigated the relationship between FLI and incident type 2 diabetes (T2DM) independent of baseline insulin resistance status. Therefore, this study aimed to evaluate the association between FLI and incident T2DM and to determine whether FLI could be used as an indicator of T2DM using a large-sample, community-based Korean cohort over 12 years.

METHODS

Among the 10,030 total participants, 7,777 (3,676 men and 4,101 women) without diabetes were selected from the Korean Genome and Epidemiology Study (KoGES). FLI grade, which ranged from 0 to 100, was categorized into three groups: low, FLI (< 30); intermediate, FLI (30-59); and high, FLI (≥ 60). The hazard ratios (HRs) with 95% confidence intervals (CIs) for incident T2DM were calculated using multivariate Cox proportional hazards regression models after adjusting for potentially confounding variables.

RESULTS

In total, 1,490 individuals (19.2%) developed T2DM during follow-up. Compared to the reference FLI (< 30), the HRs of incident T2DM for the FLI (30-59), and FLI (≥ 60) increased after adjusting for potentially confounding variables, including the HOMA-IR marker.

CONCLUSIONS

FLI grade at baseline could be a future indicator of T2DM even when prior glucose or insulin (HOMA-IR) levels are normal.

Advancements in MAFLD Modeling with Human Cell and Organoid Models

Metabolic (dysfunction) associated fatty liver disease (MAFLD) is one of the most prevalent liver diseases and has no approved therapeutics. The high failure rates witnessed in late-phase MAFLD drug trials reflect the complexity of the disease, and how the disease develops and progresses remains to be fully understood. In vitro, human disease models play a pivotal role in mechanistic studies to unravel novel disease drivers and in drug testing studies to evaluate human-specific responses. This review focuses on MAFLD disease modeling using human cell and organoid models. The spectrum of patient-derived primary cells and immortalized cell lines employed to model various liver parenchymal and non-parenchymal cell types essential for MAFLD development and progression is discussed. Diverse forms of cell culture platforms utilized to recapitulate tissue-level pathophysiology in different stages of the disease are also reviewed.

Rifaximin and lubiprostone mitigate liver fibrosis development by repairing gut barrier function in diet-induced rat steatohepatitis

BACKGROUND

Although gut-derived lipopolysaccharide (LPS) affects the progression of non-alcoholic steatohepatitis (NASH) pathogenesis, few studies have focused on this relationship to develop treatments for NASH.

AIMS

To explore the effects of combination with rifaximin and lubiprostone on NASH liver fibrosis through the modulation of gut barrier function.

METHODS

To induce steatohepatitis, F344 rats were fed a choline-deficient l-amino acid-defined (CDAA) diet for 12 weeks and received oral administration of rifaximin and/or lubiprostone. Histological, molecular, and fecal microbial analyses were performed. Barrier function in Caco-2 cells were assessed by in vitro assays.

RESULTS

Combination rifaximin/lubiprostone treatment significantly suppressed macrophage expansion, proinflammatory responses, and liver fibrosis in CDAA-fed rats by blocking hepatic translocation of LPS and activation of toll-like receptor 4 signaling. Rifaximin and lubiprostone improved intestinal permeability via restoring tight junction proteins (TJPs) with the intestinal activation of pregnane X receptor and chloride channel-2, respectively. Moreover, this combination increased the abundance of Bacteroides, Lactobacillus, and Faecalibacterium as well as decreased that of Veillonella resulting in an increase of fecal short-chain fatty acids and a decrease of intestinal sialidase activity. Both agents also directly suppressed the LPS-induced barrier dysfunction and depletion of TJPs in Caco-2 cells.

CONCLUSION

The combination of rifaximin and lubiprostone may provide a novel strategy for treating NASH-related fibrosis.

Extrahepatic morbidities and mortality of NAFLD: an umbrella review of meta-analyses

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) has reached pandemic proportions currently and may contribute to multiple extrahepatic outcomes.

AIM

To comprehensively summarise evidence of associations between NAFLD and risk of extrahepatic outcomes.

METHODS

We conducted an umbrella review. We searched PubMed, Web of Science and Cochrane database from inception to 27 November 2021.

RESULTS

We included 22 meta-analyses with 374 original studies in our analysis. Subjects with NAFLD had an increased risk of mortality, multiple cardiovascular complications, extrahepatic cancers, diabetes and chronic kidney disease (CKD) than those without NAFLD. Excess risks of several other extrahepatic outcomes including hypothyroidism, urolithiasis, gastro-oesophageal reflux disease, gallstones, depression and worse maternal and foetal outcomes were also observed in this population. However, associations were not significant for prostate cancer, female organ genital cancer, haematological cancer, diabetic retinopathy or osteoporotic fracture. The risks of CVD, diabetes and CKD were similar in obese and non-obese patients. Most associations were heterogeneous across regions; significantly, Europeans with NAFLD were more prone to all-cause mortality than North Americans. The certainty of evidence was graded from only very low to moderate as all included studies were observational.

CONCLUSIONS

Patients with NAFLD are at heightened risk of extrahepatic outcomes. However, the certainty of evidence is only from very low to moderate. Further studies at low risk of bias are required to support the evidence and elucidate any causal associations.

Metabolic dysfunction-associated fatty liver disease directly related to liver fibrosis independent of insulin resistance, hyperlipidemia, and alcohol intake in morbidly obese patients

AIM

Hepatic fibrosis is associated with various factors, including metabolic dysfunction-associated fatty liver disease (MAFLD), insulin resistance, and alcohol intake in patients with morbid obesity. We investigated factors directly associated with hepatic fibrosis in patients with morbid obesity using a graphical model.

METHODS

We enrolled 134 consecutive patients with morbid obesity who underwent liver biopsy during sleeve gastrectomy (median age 43.5 years; MAFLD 78.4%; homeostasis model assessment of insulin resistance [HOMA-IR] 5.97; >20 g/day alcohol intake 14.2%). Patients were classified into none/mild (F0/1; n = 77) or significant/advanced fibrosis (F2/3; n = 57) groups, based on histology. Factors associated with F2/3 were analyzed using logistic regression analysis and a graphical model.

RESULTS

F2/3 was observed in 42.5% of the enrolled patients. The prevalence of MAFLD and HOMA-IR values were significantly higher in the F2/3 group than in the F0/1 group; however, no significant difference in alcohol intake was observed between the two groups. On logistic regression analysis, MAFLD, but not HOMA-IR or alcohol intake, was the only independent factor associated with F2/3 (odds ratio 7.555; 95% confidence interval 2.235-25.544; p = 0.0011). The graphical model revealed that F2/3 directly interacted with MAFLD, diabetes mellitus, HOMA-IR, and low-density lipoprotein cholesterol. Among these factors, MAFLD showed the strongest interaction with F2/3.

CONCLUSIONS

We determined that MAFLD was more directly associated with significant/advanced fibrosis than insulin resistance or hyperlipidemia, and alcohol intake was not directly associated with hepatic fibrosis. Metabolic dysfunction-associated fatty liver disease could be the most important factor for hepatic fibrosis in patients with morbid obesity.

Immune mechanisms linking metabolic injury to inflammation and fibrosis in fatty liver disease - novel insights into cellular communication circuits

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease and is emerging as the leading cause of cirrhosis, liver transplantation and hepatocellular carcinoma (HCC). NAFLD is a metabolic disease that is considered the hepatic manifestation of the metabolic syndrome; however, during the evolution of NAFLD from steatosis to non-alcoholic steatohepatitis (NASH), to more advanced stages of NASH with liver fibrosis, the immune system plays an integral role. Triggers for inflammation are rooted in hepatic (lipid overload, lipotoxicity, oxidative stress) and extrahepatic (gut-liver axis, adipose tissue, skeletal muscle) systems, resulting in unique immune-mediated pathomechanisms in NAFLD. In recent years, the implementation of single-cell RNA-sequencing and high dimensional multi-omics (proteogenomics, lipidomics) and spatial transcriptomics have tremendously advanced our understanding of the complex heterogeneity of various liver immune cell subsets in health and disease. In NAFLD, several emerging inflammatory mechanisms have been uncovered, including profound macrophage heterogeneity, auto-aggressive T cells, the role of unconventional T cells and platelet-immune cell interactions, potentially yielding novel therapeutics. In this review, we will highlight the recent discoveries related to inflammation in NAFLD, discuss the role of immune cell subsets during the different stages of the disease (including disease regression) and integrate the multiple systems driving inflammation. We propose a refined concept by which the immune system contributes to all stages of NAFLD and discuss open scientific questions arising from this paradigm shift that need to be unravelled in the coming years. Finally, we discuss novel therapeutic approaches to target the multiple triggers of inflammation, including combination therapy via nuclear receptors (FXR agonists, PPAR agonists).

Old and new classes of glucose-lowering agents as treatments for non-alcoholic fatty liver disease: A narrative review

Non-alcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease with a global prevalence of about 55% in people with type 2 diabetes mellitus (T2DM). T2DM, obesity and NAFLD are three closely inter-related pathological conditions. In addition, T2DM is one of the strongest clinical risk factors for the faster progression of NAFLD to non-alcoholic steatohepatitis (NASH), cirrhosis and hepatocellular carcinoma. Increasing evidence suggests that newer classes of glucose-lowering drugs, such as peroxisome proliferator-activated receptor agonists, glucagon-like peptide-1 receptor agonists, dipeptidyl peptidase-4 inhibitors or sodium-glucose cotransporter-2 inhibitors, could reduce the rates of NAFLD progression. This narrative review aims to briefly summarize the recent results from randomized controlled trials testing the efficacy and safety of old and new glucose-lowering drugs for the treatment of NAFLD or NASH in adults both with and without coexisting T2DM.

Liver Stiffness on Magnetic Resonance Elastography and the MEFIB Index and Liver-Related Outcomes in Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis of Individual Participants

BACKGROUND & AIMS

Magnetic resonance elastography (MRE) is an accurate biomarker of liver fibrosis; however, limited data characterize its association with clinical outcomes. We conducted an individual participant data pooled meta-analysis on patients with nonalcoholic fatty liver disease to evaluate the association between liver stiffness on MRE and liver-related outcomes.

METHODS

A systematic search identified 6 cohorts of adults with nonalcoholic fatty liver disease who underwent a baseline MRE and were followed for hepatic decompensation, hepatocellular carcinoma, and death. Cox and logistic regression were used to assess the association between liver stiffness on MRE and liver-related outcomes, including a composite primary outcome defined as varices needing treatment, ascites, and hepatic encephalopathy.

RESULTS

This individual participant data pooled meta-analysis included 2018 patients (53% women) with a mean (± standard deviation) age of 57.8 (±14) years and MRE at baseline of 4.15 (±2.19) kPa, respectively. Among 1707 patients with available longitudinal data with a median (interquartile range) of 3 (4.2) years of follow-up, the hazard ratio for the primary outcome for MRE of 5 to 8 kPa was 11.0 (95% confidence interval [CI]: 7.03-17.1, P < .001) and for ≥ 8 kPa was 15.9 (95% CI: 9.32-27.2, P < .001), compared with those with MRE <5 kPa. The MEFIB index (defined as positive when MRE ≥3.3 kPa and Fibrosis-4 ≥1.6) had a robust association with the primary outcome with a hazard ratio of 20.6 (95% CI: 10.4-40.8, P < .001) and a negative MEFIB had a high negative predictive value for the primary outcome, 99.1% at 5 years. The 3-year risk of incident hepatocellular carcinoma was 0.35% for MRE <5 kPa, 5.25% for 5 to 8 kPa, and 5.66% for MRE ≥8 kPa, respectively.

CONCLUSION

Liver stiffness assessed by MRE is associated with liver-related events, and the combination of MRE and Fibrosis-4 has excellent negative predictive value for hepatic decompensation. These data have important implications for clinical practice.

Prepandemic Prevalence Estimates of Fatty Liver Disease and Fibrosis Defined by Liver Elastography in the United States

BACKGROUND AND AIMS

Fatty liver disease is a growing public health burden. We estimated prepandemic fatty liver disease prevalence determined by transient elastography-assessed hepatic steatosis and fibrosis, and examined associations with lifestyle and other factors in a United States population sample.

METHODS

Liver stiffness and controlled attenuation parameter (CAP) were assessed on 7923 non-Hispanic white, non-Hispanic black, non-Hispanic Asian, and Hispanic men and women aged 20 years and over in the National Health and Nutrition Examination Survey (NHANES) 2017-March 2020 prepandemic data.

RESULTS

The prevalence of fatty liver disease (CAP > 300 dB/m) was 28.8% and of fibrosis (liver stiffness > 8 kPa) was 10.4%. Only 7.2% of participants with fatty liver disease and 10.9% with fibrosis reported being told by a health care provider that they had liver disease. In addition to known risk factors such as metabolic factors and ALT, persons with fatty liver disease were less likely to meet physical activity guidelines, more likely to be sedentary for ≥ 12 h a day, and reported a less healthy diet. Persons with fibrosis were less likely to have a college degree and reported a less healthy diet.

CONCLUSIONS

In the U.S. population, most persons with fatty liver disease are unaware of their condition. Physical activity and dietary modifications might reduce the fatty liver disease burden. There is an urgent need for fatty liver disease management in high-risk individuals using transient elastography or other noninvasive methods to intervene in disease progression.

Immune checkpoint inhibitors and their impact on liver enzymes and attenuation

BACKGROUND

Immune related adverse events impacting the liver are common from immune checkpoint inhibitor (ICI) therapy; however, there is little data regarding the subclinical impact of ICIs on liver inflammation. The study aims to determine whether ICI therapy affects liver attenuation and liver enzymes in melanoma patients with and without hepatic steatosis.

METHODS

A retrospective, cohort study was conducted of patients with advanced melanoma treated with ICI therapy who received serial PET-CT scans at the Vanderbilt University Medical Center (VUMC). Primary outcomes included: liver attenuation measured by PET-CT/non-contrast CT and liver enzymes. Hepatic steatosis was diagnosed by radiologists on clinical imaging.

RESULTS

Among 839 patients with advanced melanoma treated with ICIs, 81 had serial PET-CT scans approximately 12 months apart and long-term survival; of these 11 patients had pre-existing steatosis/steatohepatitis. Overall, ICI was not associated with significant increases in liver enzymes in all patients; modest decreases in liver enzymes were observed in patients with pre-existing steatosis/steatohepatitis. Similarly, liver attenuation did not change from baseline to post-treatment (58.44 vs 60.60 HU, + 2.17, p = 0.055).

CONCLUSIONS

ICIs may not chronically affect liver enzymes or liver attenuation, a non-invasive measure of liver fat content and inflammation, in the general population or in those with pre-existing steatosis/steatohepatitis.

FASN inhibition targets multiple drivers of NASH by reducing steatosis, inflammation and fibrosis in preclinical models

Fatty acid synthase (FASN) is an attractive therapeutic target in non-alcoholic steatohepatitis (NASH) because it drives de novo lipogenesis and mediates pro-inflammatory and fibrogenic signaling. We therefore tested pharmacological inhibition of FASN in human cell culture and in three diet induced mouse models of NASH. Three related FASN inhibitors were used; TVB-3664, TVB-3166 and clinical stage TVB-2640 (denifanstat). In human primary liver microtissues, FASN inhibiton (FASNi) decreased triglyceride (TG) content, consistent with direct anti-steatotic activity. In human hepatic stellate cells, FASNi reduced markers of fibrosis including collagen1α (COL1α1) and α-smooth muscle actin (αSMA). In CD4+ T cells exposed to NASH-related cytokines, FASNi decreased production of Th17 cells, and reduced IL-1β release in LPS-stimulated PBMCs. In mice with diet induced NASH l, FASNi prevented development of hepatic steatosis and fibrosis, and reduced circulating IL-1β. In mice with established diet-induced NASH, FASNi reduced NAFLD activity score, fibrosis score, ALT and TG levels. In the CCl4-induced FAT-NASH mouse model, FASN inhibition decreased hepatic fibrosis and fibrosis markers, and development of hepatocellular carcinoma (HCC) tumors by 85%. These results demonstrate that FASN inhibition attenuates inflammatory and fibrotic drivers of NASH by direct inhibition of immune and stellate cells, beyond decreasing fat accumulation in hepatocytes. FASN inhibition therefore provides an opportunity to target three key hallmarks of NASH.

FBXW7 Reduces the Cancer Stem Cell-Like Properties of Hepatocellular Carcinoma by Regulating the Ubiquitination and Degradation of ACTL6A

Cancer stem cells (CSCs) comprise a subset of tumor cells that can initiate tumorigenesis and promote tumor advance. A previous study showed that the expression of FBXW7 in hepatocellular carcinoma (HCC) clinical samples was lower than that in the adjacent nontumor tissues and was negatively correlated with the invasion and migration of HCC cells. However, the biological characteristics and the underlying molecular mechanisms of FBXW7 in HCC stemness are yet to be elucidated. In present study, we found that FBXW7 participates in the self-renewal, tumorigenicity, sorafenib therapy, and stem cell-like properties of HCC cells in vivo and in vitro. The upregulation of FBXW7 inhibited the stemness and reduced the tumorigenicity and drug resistance of HCC cells. Mechanistically, proteins binding to FBXW7 were identified by coimmunoprecipitation and protein colocalization assays. We confirmed ACTL6A as a novel downstream target for FBXW7. The in vivo ubiquitination assay showed that FBXW7 repressed HCC malignancy by regulating the oncogenic activity of ACTL6A in a ubiquitin-dependent manner. Furthermore, we found that ACTL6A overexpression inversed the self-renewal abilities and tumorigenic abilities depressed by overexpressing FBXW7. The current findings suggested that FBXW7 reduces the stemness of HCC cells by targeting and degrading ACTL6A and provides a novel target for the diagnosis and treatment of HCC.

Non-alcoholic steatohepatitis

Non-alcoholic steatohepatitis belongs to the spectrum of metabolic-associated fatty liver diseases characterized by steatosis linked to obesity, diabetes, metabolic syndrome, dyslipidemia and immune-mediated disorders. The main features of MAFLD include high prevalence, heterogeneity, complexity and dynamic disease. Pruritus and asthenia are the main clinical manifestation that impact on quality of life and patient-reported outcomes. Biochemical or imagen-based non-invasive test have been implemented in the diagnostic process. Liver biopsy remains as the gold standard. Therapeutic options included life-style intervention. Mediterranean hypocaloric Diet to lose weight, exercise to fight sarcopenia and alcohol abstinence. In non-responders, drug-therapy focusing on obesity, diabetes and fibrosis using sequentially or combined to promote steatosis, inflammation and fibrosis regression.

Gastrointestinal and Liver Complications in Patients with Diabetes Mellitus-A Review of the Literature

The number of diabetes mellitus patients has increased over the last few years in developing countries, along with obesity and sedentary lifestyle. Besides macroangiopathy and microangiopathy, damage to the nerve fibers of the peripheral nervous system is the most common chronic complication of diabetes. Digestive complications in diabetic patients represent a consequence of diabetic autonomic neuropathy involving the gastrointestinal tract, but unfortunately not always evaluated by diabetologists. Aside from the complications encountered in the digestive tract, patients with diabetes mellitus are prone to developing liver diseases. This review will describe the prevalence of these complications, the modality of diagnosis, and therapeutical solutions in order to reduce the risk of progression of these complications in diabetic subjects.

Elevated liver enzymes predict morbidity and mortality despite antiviral cure in patients with chronic hepatitis C: Data from the German Hepatitis C-Registry

While direct-acting antivirals (DAAs) cure chronic hepatitis C virus (HCV) infection in almost all patients, some patients remain at risk of liver disease despite HCV cure. In order to identify risk factors indicating liver-related morbidity and death after viral cure, we included 6982 patients from the national multicenter real-world German Hepatitis C Registry with regular follow-up visits for up to 7 years after DAA therapy. Definitions for normal liver function tests (in women/men) were alanine aminotransferase (ALT; ≤35/≤50 U/L), ALT according to American Association for the Study of Liver Diseases (AASLD; ≤19/≤30 U/L), and gamma-glutamyltransferase (GGT; ≤40/≤60 U/L). In our cohort, 97.4% of patients achieved sustained virologic response (SVR). At 24 weeks after SVR (SVR24), elevated ALT occurred in 657/6982 (9.4%), elevated ALT (AASLD) in 2609/6982 (37.4%), and elevated GGT in 1777/6982 (25.5%) patients. Risk factors for increased ALT at SVR24 were obesity, alcohol, cirrhosis, elevated baseline ALT, and non-SVR. Increased GGT at SVR24 was significantly (p < 0.05) and independently associated with male sex (odds ratio [OR], 2.12), higher body mass index (OR, 1.04), age >50 years (OR, 1.60), liver cirrhosis (OR, 3.97), alcohol consumption (OR, 2.99), diabetes (OR, 1.63), non-SVR (OR, 8.00), and elevated GGT at baseline (OR, 17.12). In multivariate regression analysis, elevated GGT at SVR24, particularly in combination with cirrhosis, was the best predictor for hepatic decompensation, hepatocellular carcinoma development, and death, followed by elevated ALT (AASLD) and standard ALT, which predicted hepatic decompensation. Despite successful HCV therapy, elevated GGT at SVR24 and to a lesser extent ALT are predictive of the future clinical outcome and linked with liver-associated comorbidities. This may highlight the relevance of nonalcoholic fatty liver disease, diabetes mellitus, alcohol, and cirrhosis for the clinical outcome in a vulnerable population, even after HCV cure.

Combination of tofogliflozin and pioglitazone for NAFLD: Extension to the ToPiND randomized controlled trial

The incidence of nonalcoholic fatty liver disease (NAFLD) has recently increased and is related to obesity and the associated surge in type 2 diabetes mellitus (T2DM) and metabolic syndromes. This trial follows up on our previous work and forms part of the ToPiND study. We aimed to combine tofogliflozin and pioglitazone treatment for hepatic steatosis in patients with NAFLD and T2DM. In this open-label, prospective, single-center, randomized clinical trial, patients with NAFLD with T2DM and a hepatic fat fraction of ≥10% were assessed based on magnetic resonance imaging proton density fat fraction. Eligible patients received either 20 mg tofogliflozin or 15-30 mg pioglitazone orally, once daily for 24 weeks, followed by combination therapy with both medicines for an additional 24 weeks. The effects on diabetes mellitus and hepatic steatosis were examined at baseline and after the completion of monotherapy and combination therapy. Thirty-two eligible patients received the combination therapy of tofogliflozin and pioglitazone. The combination therapy showed additional improvement in glycated hemoglobin compared with each monotherapy group and showed improvement in steatosis, hepatic stiffness, and alanine aminotransferase levels compared with the tofogliflozin monotherapy group. Pioglitazone monotherapy-mediated increase in body weight decreased following concomitant use of tofogliflozin. The combination therapy resulted in lower triglyceride, higher high-density lipoprotein cholesterol, higher adiponectin, and higher ketone body levels. Conclusion: In addition to the additive effects of tofogliflozin and pioglitazone in patients with T2DM and NAFLD, combination therapy was suggested to reduce weight gain and induce cardioprotective effect. Further studies with more patients are needed to investigate the combination therapy of various drugs.

Analysis of a Simulation Model to Estimate Long-term Outcomes in Patients with Nonalcoholic Fatty Liver Disease

IMPORTANCE

Quantitative assessment of disease progression in patients with nonalcoholic fatty liver disease (NAFLD) has not been systematically examined using competing liver-related and non-liver-related mortality.

OBJECTIVE

To estimate long-term outcomes in NAFLD, accounting for competing liver-related and non-liver-related mortality associated with the different fibrosis stages of NAFLD using a simulated patient population.

DESIGN, SETTING, AND PARTICIPANTS

This decision analytical modeling study used individual-level state-transition simulation analysis and was conducted from September 1, 2017, to September 1, 2021. A publicly available interactive tool, dubbed NAFLD Simulator, was developed that simulates the natural history of NAFLD by age and fibrosis stage at the time of (hypothetical) diagnosis defined by liver biopsy. Model health states were defined by fibrosis states F0 to F4, decompensated cirrhosis, hepatocellular carcinoma (HCC), and liver transplant. Simulated patients could experience nonalcoholic steatohepatitis resolution, and their fibrosis stage could progress or regress. Transition probabilities between states were estimated from the literature as well as calibration, and the model reproduced the outcomes of a large observational study.

EXPOSURE

Simulated natural history of NAFLD.

MAIN OUTCOMES AND MEASURES

Main outcomes were life expectancy; all cause, liver-related, and non-liver-related mortality; and cumulative incidence of decompensated cirrhosis and/or HCC.

RESULTS

The model included 1 000 000 simulated patients with a mean (range) age of 49 (18-75) years at baseline, including 66% women. The life expectancy of patients aged 49 years was 25.3 (95% CI, 20.1-29.8) years for those with F0, 25.1 (95% CI, 20.1-29.4) years for those with F1, 23.6 (95% CI, 18.3-28.2) years for those with F2, 21.1 (95% CI, 15.6-26.3) years for those with F3, and 13.8 (95% CI, 10.3-17.6) years for those with F4 at the time of diagnosis. The estimated 10-year liver-related mortality was 0.1% (95% uncertainty interval [UI], <0.1%-0.2%) in F0, 0.2% (95% UI, 0.1%-0.4%) in F1, 1.0% (95% UI, 0.6%-1.7%) in F2, 4.0% (95% UI, 2.5%-5.9%) in F3, and 29.3% (95% UI, 21.8%-35.9%) in F4. The corresponding 10-year non-liver-related mortality was 1.8% (95% UI, 0.6%-5.0%) in F0, 2.4% (95% UI, 0.8%-6.3%) in F1, 5.2% (95% UI, 2.0%-11.9%) in F2, 9.7% (95% UI, 4.3%-18.1%) in F3, and 15.6% (95% UI, 10.1%-21.7%) in F4. Among patients aged 65 years, estimated 10-year non-liver-related mortality was higher than liver-related mortality in all fibrosis stages (eg, F2: 16.7% vs 0.8%; F3: 28.8% vs 3.0%; F4: 40.8% vs 21.9%).

CONCLUSIONS AND RELEVANCE

This decision analytic model study simulated stage-specific long-term outcomes, including liver- and non-liver-related mortality in patients with NAFLD. Depending on age and fibrosis stage, non-liver-related mortality was higher than liver-related mortality in patients with NAFLD. By translating surrogate markers into clinical outcomes, the NAFLD Simulator could be used as an educational tool among patients and clinicians to increase awareness of the health consequences of NAFLD.

Thyroid hormones as a disease modifier and therapeutic target in nonalcoholic steatohepatitis

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide and closely interconnected to the metabolic syndrome. Liver-specific and systemic signaling pathways orchestrating glucose and fatty acid metabolism contribute to intrahepatic accumulation of lipids and inflammatory processes eventually causing disease progression to nonalcoholic steatohepatitis (NASH), liver fibrosis, and cirrhosis. Since a high number of key regulatory genes regarding liver homeostasis are directly mediated via thyroid hormone (TH) signaling, targeting TH receptors (TRs) represent a promising therapeutic potential for the treatment of NAFLD.

AREAS COVERED

In this review, we elucidate the effects of TH on metabolic regulations in the liver via local availability and actions. We discuss recent advances and the potential impact of thyromimetics in basic research and clinical trials including liver-targeted and TRβ-specific agents for the treatment of NAFLD.

EXPERT OPINION

Unselective TR targeting can be accompanied by negative side effects due to high TRβ expression in other organs and TRα-mediated effects. Recent advances in drug development and the introduction of liver-targeted thyromimetics selectively activating TRβ such as Resmetirom (MGL-3196) and VK2809 bring new hope of translating the knowledge on local TH effects into effective hepatic lipid-clearing therapies against NASH.

Structured Early detection of Asymptomatic Liver Cirrhosis: Results of the population-based liver screening program SEAL

BACKGROUND & AIMS

Detection of patients with early cirrhosis is of importance to prevent the occurrence of complications and improve prognosis. The SEAL program aimed at evaluating the usefulness of a structured screening procedure to detect cirrhosis as early as possible.

METHODS

SEAL was a prospective cohort study with a control cohort from routine care data. Individuals participating in the general German health check-up after the age of 35 ("Check-up 35") at their primary care physicians were offered a questionnaire, liver function tests (aspartate and alanine aminotransferase [AST and ALT]), and follow-up. If AST/ALT levels were elevated, the AST-to-platelet ratio index (APRI) score was calculated, and patients with a score >0.5 were referred to a liver expert in secondary and/or tertiary care.

RESULTS

A total of 11,859 participants were enrolled and available for final analysis. The control group comprised 349,570 participants of the regular Check-up 35. SEAL detected 488 individuals with elevated APRI scores (4.12%) and 45 incident cases of advanced fibrosis/cirrhosis. The standardized incidence of advanced fibrosis/cirrhosis in the screening program was slightly higher than in controls (3.83‰ vs. 3.36‰). The comparison of the chance of fibrosis/cirrhosis diagnosis in SEAL vs. in standard care was inconclusive (marginal odds ratio 1.141, one-sided 95% CI 0.801, +Inf). Of note, when patients with decompensated cirrhosis at initial diagnosis were excluded from both cohorts in a post hoc analysis, SEAL was associated with a 59% higher chance of early cirrhosis detection on average than routine care (marginal odds ratio 1.590, one-sided 95% CI 1.080, +Inf; SEAL 3.51‰, controls: 2.21‰).

CONCLUSIONS

The implementation of a structured screening program may increase the early detection rate of cirrhosis in the general population. In this context, the SEAL pathway represents a feasible and potentially cost-effective screening program.

REGISTRATION

DRKS00013460 LAY SUMMARY: Detection of patients with early liver cirrhosis is of importance to prevent the occurrence of complications and improve prognosis. This study demonstrates that the implementation of a structured screening program using easily obtainable measures of liver function may increase the early detection rate of cirrhosis in the general population. In this context, the 'SEAL' pathway represents a feasible and potentially cost-effective screening program.

Noninvasive Algorithms for the Case Finding of "At-Risk" Patients with NAFLD

Despite the high prevalence of non-alcoholic fatty liver disease (NAFLD) in primary care (25%), only a small minority (< 5%) of NAFLD patients will develop advanced liver fibrosis. The challenge is to identify these patients, who are at the greatest risk of developing complications and need to be referred to liver clinics for specialized management. The focus should change from patients with abnormal liver tests toward patients "at risk of NAFLD," namely those with metabolic risk factors, such as obesity and type 2 diabetes. Non-invasive tests are well validated for diagnosing advanced fibrosis. Algorithms using FIB-4 as the first-line test, followed, if positive (≥ 1.3), by transient elastography or a patented blood test are the best strategy to define pathways for "at-risk" NAFLD patients from primary care to liver clinics. Involving general practitioners actively and raising their awareness regarding NAFLD and non-invasive tests are critical to establish such pathways.

Specific Challenges in Geriatric Cirrhosis and Hepatic Encephalopathy

As the world's population ages, diseases predominantly found in the elderly now overlap with diseases that were thought to be the purview of younger patients. This includes chronic liver disease, which affects more than 2 billion people worldwide. Owing to the obesity epidemic (and associated metabolic diseases), nonalcoholic fatty liver disease has become the most common cause of chronic liver disease and cirrhosis. A major complication of cirrhosis is hepatic encephalopathy (HE), which becomes challenging to diagnose in elderly patients. HE is usually included in the differential diagnosis of acute delirium but not of reversible dementias. To illustrate this point, we present 2 cases of older patients that were misdiagnosed as having dementia and Parkinson's disease or a parkinsonian syndrome but had contributions from cirrhosis. Both cognitive impairment and tremor resolved with treatment of HE.