Disease State Transition Probabilities Across the Spectrum of NAFLD: A Systematic Review and Meta-Analysis of Paired Biopsy or Imaging Studies

A cluster randomized trial of a Multicomponent Clinical Care Pathway (MCCP) to improve MASLD diagnosis and management in primary care: study protocol

BACKGROUND

Metabolic dysfunction associated steatotic liver disease (MASLD) is the most common chronic liver disorder in the world. Most patients with MASLD are undiagnosed, untreated and unreferred. Treatment depends on diagnosis and accurate staging of fibrosis risk, and therefore screening at the primary care setting coupled with consistent, timely, evidence-based, widely accessible, and testable management processes is critical. Randomized controlled trials of methods for screening, diagnosis, severity stratification, and referral are lacking. We previously validated the MASLD clinical care pathway (MCCP), a multistep algorithmic process geared to support primary care settings in screening, diagnosis, risk stratification, and suggested referral and treatment of patients with MASLD. We will evaluate the effectiveness of the MCCP intervention compared to usual care in improving MASLD care process and patient outcomes.

METHODS

A two-arm, parallel, cluster-randomized trial will assess the effect of the MCCP intervention comprised of an e-trigger and structured provider education on screening, diagnosis, referral, and treatment for MASLD. Clusters are Veterans Affairs (VA) patient-centered primary care clinics, called Patient Aligned Care Teams (PACTs). This 4-year study will include three phases: (1) formative assessment to explore barriers to feasibility and acceptability of intervention among providers and patients and adapt MCCP for utilization by VA PACTs, (2) cluster-randomized trial to examine the effectiveness of the MCCP compared to usual care, and (3) summative evaluation to identify patient and provider characteristics associated with effectiveness of MCCP and plan for future implementation. The primary outcome will be a composite dichotomous variable for making a new MASLD diagnosis and completing severity risk stratification of MASLD. Secondary outcomes include referral and receipt of hepatology specialty care for patients with MASLD and advanced fibrosis.

DISCUSSION

Our randomized controlled trial will be the first to systematically implement the MCCP using strategies that are clinically relevant, adaptable and scalable. If successful, the MCCP will improve outcomes for patients with MASLD through early detection, accurate risk stratification, and timely treatment within primary care settings.

TRIAL REGISTRATION

This trial has been registered on clinicaltrails.gov (# NCT06671886), registration date: 10-31-2024.

Metabolic dysfunction-associated steatotic liver disease and its associated health risks

This article synthesizes the current knowledge on the epidemiology of metabolic dysfunction-associated steatotic liver disease (MASLD), its associated risks, and its genetic determinants. The findings presented in this article can be used to develop clinical strategies to reduce MASLD's growing global burden. MASLD has become a major global health concern due to increasing rates of obesity, sedentary lifestyles, and metabolic disorders. MASLD is a leading cause of end-stage liver diseases, including cirrhosis and hepatocellular carcinoma (HCC), and MASLD also significantly increases the risk of cardiovascular disease (CVD), thereby exerting dual effects on liver and cardiovascular health. MASLD was once referred to as nonalcoholic fatty liver disease, and this change in nomenclature reflects a growing focus on its metabolic underpinnings, facilitating the more precise diagnosis and clinical management of this disease. Epidemiological studies have demonstrated that the prevalence of MASLD is increasing worldwide, although the prevalence varies across regions and populations. Noninvasive diagnostic tools such as ultrasound and fatty liver indices along with biomarkers such as alanine aminotransferase (ALT) are crucial for early detection and risk stratification. Genetic research has identified key gene variants, including PNPLA3 (rs738409) and TM6SF2 (rs58542926), that influence MASLD susceptibility and progression, and these findings have created opportunities for improving precision medicine with respect to treating MASLD. Research has revealed an association between MASLD and major adverse cardiovascular events and increased mortality, which highlights the importance of integrating cardiovascular risk management into treatment strategies for MASLD. Future research should focus on advancing noninvasive diagnostics, leveraging genetic insights to provide tailored care, and implementing population-specific interventions to address regional variations.

Pharmaco-Economic Assessment of Screening Strategies for High-Risk MASLD in Primary Care

BACKGROUND AND AIMS

Several scientific associations recommend a sequential combination of non-invasive tests (NITs) to identify high-risk MASLD patients but their cost-effectiveness is unknown.

METHODS

A cost-utility model was developed to assess the incremental cost-effectiveness ratio (ICER) of recommended screening strategies for patients with clinically suspected MASLD, specifically those with type 2 diabetes (T2D) and obesity with multiple cardiometabolic risk factors which will be initiated in primary care. Six screening strategies were assessed, using either vibration-controlled transient elastography (VCTE) or the enhanced liver fibrosis (ELF) test as a second-line test following an initial Fibrosis-4 (FIB-4) assessment as the first line NIT. The model included treatment effects of resmetirom for metabolic dysfunction-associated steatohepatitis (MASH) patients with F2 or F3 fibrosis.

RESULTS

All screening strategies for high-risk MASLD in US incurred additional costs compared to no screening, ranging from $13 587 to $14 730 per patient with T2D and $14 274 to $15 661 per patient with obesity. However, screening reduced long-term costs, ranging from $22 150 to $22 279 per patient with T2D and $13 704 to $13 705 per patient with obesity, compared to $24 221 and $14 956 for no screening, respectively. ICERs ranged from $26 913 to $27 884 per QALY for T2D patients and $23 265 to $24  992 per QALY for patients with obesity. While ICERs were influenced by VCTE availability, they remained cost-effective when using ELF as the second-line test. Our findings remain robust across a range of key parameters.

CONCLUSIONS

Screening for high-risk MASLD is cost-effective according to recent guidelines. Implementing these screening strategies in primary care should be considered.

Economic evaluation of non-invasive test pathways for high-risk metabolic dysfunction-associated steatotic liver disease (MASLD) in the United Kingdom (UK)

INTRODUCTION AND OBJECTIVES

Non-invasive tests (NITs) identifying high-risk MASLD in primary care is suggested but, these strategies cost-effectiveness remain uncertain in the United Kingdom (UK).

MATERIALS AND METHODS

A cost-utility/budget impact model was developed for cost-effectiveness evaluation of two screening strategies (1) FIB-4 followed by Enhanced Liver Fibrosis (ELF) (FIB-4/ELF); (2) FIB-4 followed by Transient Elastography (FIB-4/TE) compared to standard of care (SoC). A cohort of primary care MASLD patients with an advanced fibrosis prevalence of 4.20 % was simulated. A decision tree classified patients as true positives, false positives, true negatives, or false negatives based on NIT diagnostic accuracy, followed by a 3-year Markov model to estimate costs and quality-adjusted life years (QALYs). The model included 11 health states: MASLD, fibrosis stages (F0-F3), cirrhosis, decompensated cirrhosis, liver transplant, and death. Costs came from the National Tariff, National Schedule of Costs and Personal Social Services Research Unit.

RESULTS

SoC had a false diagnosis rate of 36.26 %, while FIB-4 with ELF or TE reduced false positive rates to 23.20 % and 20.91 %, respectively. Compared to 112,807 unnecessary hepatology referrals under SoC, FIB-4/ELF or FIB-4/TE reduced unnecessary referrals by 38,031 (33.71 %) and 45,767 (40.57 %), respectively. Both strategies demonstrated cost-effectiveness relative to SoC with total cost per patient of GBP 983.37 for FIB-4/TE, GBP 993.15 for FIB-4/ELF compared to SoC, GBP 1,014.15.

CONCLUSIONS

Sequential NIT screening strategies, combining FIB-4 with ELF or TE, are cost-saving, reduce unnecessary hepatology referrals, and offer an efficient (improve outcomes and reduce healthcare costs) approach for managing high-risk MASLD in UK primary care.

Gut Microbiota at the Crossroad of Hepatic Oxidative Stress and MASLD

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a prevalent chronic liver condition marked by excessive lipid accumulation in hepatic tissue. This disorder can lead to a range of pathological outcomes, including metabolic dysfunction-associated steatohepatitis (MASH) and cirrhosis. Despite extensive research, the molecular mechanisms driving MASLD initiation and progression remain incompletely understood. Oxidative stress and lipid peroxidation are pivotal in the "multiple parallel hit model", contributing to hepatic cell death and tissue damage. Gut microbiota plays a substantial role in modulating hepatic oxidative stress through multiple pathways: impairing the intestinal barrier, which results in bacterial translocation and chronic hepatic inflammation; modifying bile acid structure, which impacts signaling cascades involved in lipidic metabolism; influencing hepatocytes' ferroptosis, a form of programmed cell death; regulating trimethylamine N-oxide (TMAO) metabolism; and activating platelet function, both recently identified as pathogenetic factors in MASH progression. Moreover, various exogenous factors impact gut microbiota and its involvement in MASLD-related oxidative stress, such as air pollution, physical activity, cigarette smoke, alcohol, and dietary patterns. This manuscript aims to provide a state-of-the-art overview focused on the intricate interplay between gut microbiota, lipid peroxidation, and MASLD pathogenesis, offering insights into potential strategies to prevent disease progression and its associated complications.

Estimated Burden of Metabolic Dysfunction-Associated Steatotic Liver Disease in US Adults, 2020 to 2050

Importance

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common cause of chronic liver disease and is projected to become the leading indication for liver transplant (LT) in the US. Understanding its clinical burden can help to identify opportunities for prevention and treatment.

Objective

To project the burden of MASLD in US adults from 2020 to 2050.

Design, Setting, and Participants

This decision analytical modeling study used an agent-based state transition model that simulates the natural history of MASLD progression among adults 18 years of age or older. Primary data sources for model inputs were the published literature.

Exposure

Natural history of MASLD.

Main Outcomes and Measures

Cases of MASLD, metabolic dysfunction-associated steatohepatitis (MASH), fibrosis, hepatocellular carcinoma (HCC), LT, and liver-related death.

Results

The model simulated 2 821 624 individuals (mean age. 35.8 years; 50.9% female). The model predicted a steady increase in the prevalence of MASLD from 33.7% (86.3 million people) in 2020 to 41.4% (121.9 million people) by 2050. Cases of MASH would increase from 14.9 million (5.8% of US adults) in 2020 to 23.2 million (7.9% of US adults) by 2050. The number of cases of MASH and clinically significant fibrosis (ie, F≥F2, centrilobular and periportal fibrosis or more severe disease) were estimated to increase from 6.7 million to 11.7 million. By 2046 to 2050, MASLD would cause 22 440 new cases of HCC and 6720 new cases of LT per year compared with 11 483 new cases of HCC and 1717 new cases of LT in 2020 to 2025. Liver-related mortality was estimated to increase from 30 500 deaths (1.0% of all-cause deaths in adults) in 2020 to 95 300 deaths (2.4%) in 2050.

Conclusions and Relevance

In this decision analytical modeling study, the model forecast a substantial increase in clinical burden of MASLD over the next 3 decades in the absence of effective treatments. These results suggest that health systems should plan for large increases in the number of HCC cases and in the need for LT.

Metabolic dysfunction-associated steatotic liver disease: a key factor in hepatocellular carcinoma therapy response

The conceptual evolution of non-alcoholic fatty liver disease (NAFLD) to what, since 2023, is called metabolic dysfunction-associated steatotic liver disease (MASLD) not only represents a change in the classification and definition of the disease but also reflects a broader understanding of this heterogeneous condition, which still with many aspects to refine. Although the definition of NAFLD can be interchanged to a high percentage with the new MASLD concept in different aspects, MASLD has been proposed as a relevant factor that influences the response to new immunotherapeutic treatments in the management of MASLD-related hepatocellular carcinoma (HCC), compared to HCC of other etiologies. This indicates that the etiology of HCC plays a relevant role in the prognosis, highlighting the urgency of evaluating treatment regimens for this subgroup of patients in upcoming clinical trials. A better understanding of the pathophysiology of MASLD generates strategies that not only aid in its management but also provide strategies to directly intervene in the carcinogenesis of HCC.

Liver Fibrosis in Some Patients with Non-Alcoholic Fatty Liver Disease: from Diagnosis to Prognosis

The purpose of this publication was to update knowledge about non-alcoholic fatty liver disease (NAFLD) and fibrogenesis, as well as factors that have a positive or negative prognostic value in relation to the formation and progression of liver fibrosis. This review article contains the current literature dates about pathogenetic factors of the development of liver fibrosis in NAFLD and conceptual ideas about its diagnosis at this moment. Obviously, along with genetic and epigenetic factors, hyper- and disproduction of organokines affect to the progression of the disease. Evaluation of the quantitative and qualitative composition of the microbiota, the integrity of the epithelial intestinal barrier are perceptual fields for research this problem. Non-invasive proprietary and non-proprietary scales for assessing the risk of steatosis and fibrosis, transient elastometry are suitable for routine assessment of individual risk of disease development and progression. This scientific review demonstrates proofs of necessity to develop individual strategies for the management of patients with NAFLD in relation to its metabolic activity and the stage of liver fibrosis.

Serum-free light chains as a dependable biomarker for stratifying patients with metabolic dysfunction-associated steatotic liver disease

BACKGROUND AND AIMS

Adaptive immunity is gaining a significant role in progression of metabolic dysfunction-associated steatotic liver disease (MASLD). B-cell activity can be assessed by serum-free light chains (sFLCs) k and λ levels. The objective of the present investigation is to examine the utility of sFLCs as non-invasive biomarkers for the stratification of MASLD.

METHODS

We enrolled a consecutive cohort from an outpatient liver unit. Diagnosis of metabolic dysfunction-associated steatohepatitis (MASH) was made with liver biopsy according to current guidelines. Compensated advanced chronic liver disease (cACLD) and clinically significant portal hypertension (CSPH) were defined according to Baveno VII criteria. sFLCs were measured by turbidimetry using an immunoassay.

RESULTS

We evaluated 254 patients, 162/254 (63.8%) were male. Median age was 54 years old, and the median body mass index was 28.4 kg/m2. A total of 157/254 (61.8%) subjects underwent liver biopsy: 88 had histological diagnosis of MASH, 89 were considered as simple metabolic dysfunction-associated steatotic liver (MASL) and 77/254 (30.3%) patients with compensated metabolic dysfunction-associated cirrhosis. By using Baveno VII criteria, 101/254 (39.7%) patients had cACLD; among them, 45/101 (44.5%) had CSPH. Patients with cACLD showed higher sFLC levels compared with patients without cACLD (p < .01), and patients with CSPH showed higher sFLC levels than patients without CSPH (p < .01). At multivariable analysis, sFLCs were associated with cACLD (p < .05) independently from γ-globulins and other known dysmetabolic risk factors. κFLC was associated with CSPH (p < .05) independently from γ-globulins and other known dysmetabolic risk factors.

CONCLUSION

sFLCs could be a simple biomarker for stratification of cACLD in MASLD patients.

Natural history and progression of metabolic dysfunction-associated steatotic liver disease

The natural history of metabolic dysfunction-associated steatotic liver disease (MASLD), previously referred to as non-alcoholic fatty liver disease (NAFLD), is complex and long. A minority of patients develop inflammation and risk progressive fibrosis that can result in cirrhosis. Progression to cirrhosis occurs in 3-5% of patients and often takes more than 20 years. This narrative review presents an update on the natural history of MASLD, discussing studies and risk estimates for progression to severe outcomes, such as decompensated cirrhosis or hepatocellular carcinoma. We highlight the dynamic progression of liver damage, how to identify patients whose disease progresses over time, and how risk factors might be mitigated to reduce the risk for disease progression.

A novel experimental mouse model of diabetic nonalcoholic steatohepatitis: A critical role for acid-sensitive Ion Channel 1a

BACKGROUND

A two-way relationship exists between type 2 diabetes (T2DM) and human nonalcoholic steatohepatitis (NASH). Several diabetic NASH models have the disadvantages of long cycles or inconsistent with the actual incidence of human disease, which would be costly and time-consuming to investigate disease pathogenesis and develop drugs. Therefore, there is an urgent need to establish a diabetic NASH mouse model.

METHODS

The combination between Fructose-palmitate-cholesterol diet (FPC) and Streptozotocin (STZ) (FPC+STZ) was used to construct diabetic NASH mouse model. The in vivo effects of silencing acid-sensitive Ion Channel 1a (ASIC1a) were examined with an adeno-associated virus 9 (AAV9) carrying ASIC1a short hairpin RNA (shRNA) in FPC+STZ model.

RESULTS

The mice fed with FPC for 12 weeks had insulin resistance, hyperinsulinemia, lipid accumulation, and increased hepatic levels of inflammatory factors. However, it still did not develop remarkable liver fibrosis. Most interestingly, noticeable fibrotic scars were observed in the liver of mice from FPC+STZ group. Furthermore, insulin therapy significantly ameliorated FPC+STZ-induced NASH-related liver fibrosis, indicating that hyperglycemia is of great significance in NASH development and progression. Importantly, ASIC1a was found to be involved in the pathogenesis of diabetic NASH as demonstrated that silencing ASIC1a in HSCs significantly ameliorated FPC+STZ-induced NASH fibrosis. Mechanistically, ASIC1a interacted with Poly Adp-adenosine ribose polymerase (PARP1) to promote HSC activation by inducing autophagy.

CONCLUSION

A FPC diet combined with an injection of STZ induces a diabetic NASH mouse model in a shorter period. Targeting ASIC1a may provide a novel therapeutic target for the treatment of diabetic NASH.

Spatial lipidomics reveals zone-specific hepatic lipid alteration and remodeling in metabolic dysfunction-associated steatohepatitis

Alteration in lipid metabolism plays a pivotal role in developing metabolic dysfunction-associated steatohepatitis (MASH). However, our understanding of alteration in lipid metabolism across liver zonation in MASH remains limited. Within this study, we investigated MASH-associated zone-specific lipid metabolism in a diet and chemical-induced MASH mouse model. Spatial lipidomics using mass spectrometry imaging in a MASH mouse model revealed 130 lipids from various classes altered across liver zonation and exhibited zone-specific lipid signatures in MASH. Triacylglycerols, diacylglycerols, sphingolipids and ceramides showed distinct zone-specific changes and re-distribution from pericentral to periportal localization in MASH. Saturated and monounsaturated fatty acids (FA) were the primary FA composition of increased lipids in MASH, while polyunsaturated FAs were the major FA composition of decreased lipids. We observed elevated fibrosis in the periportal region, which could be the result of observed metabolic alteration across zonation. Our study provides valuable insights into zone-specific hepatic lipid metabolism and demonstrates the significance of spatial lipidomics in understanding liver lipid metabolism. Identifying unique lipid distribution patterns may offer valuable insights into the pathophysiology of MASH and facilitate the discovery of diagnostic markers associated with liver zonation.

Research on the function of epigenetic regulation in the inflammation of non-alcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver condition, characterized by a spectrum that progresses from simple hepatic steatosis to nonalcoholic steatohepatitis, which may eventually lead to cirrhosis and hepatocellular carcinoma. The precise pathogenic mechanisms underlying NAFLD and its related metabolic disturbances remain elusive. Epigenetic modifications, which entail stable transcriptional changes without altering the DNA sequence, are increasingly recognized as pivotal. The principal forms of epigenetic modifications include DNA methylation, histone modifications, chromatin remodeling, and noncoding RNAs. These alterations participate in the regulation of hepatic lipid metabolism, insulin resistance, mitochondrial injury, oxidative stress response, and release of inflammatory cytokines, all of which are associated with the onset and progression of NAFLD. This review discussed recent advances in understanding the potential epigenetic regulation of inflammation in NAFLD. Unraveling these epigenetic mechanisms may facilitate the identification of early diagnostic biomarkers and the development of targeted therapeutic strategies for NAFLD.

The effect of weight gain and metabolic dysfunction-associated steatotic liver disease on liver fibrosis progression and regression in people with HIV

OBJECTIVE

People with HIV (PWH) have high risk of liver fibrosis. We investigated the effect of weight gain and metabolic dysfunction-associated steatotic liver disease (MASLD) on liver fibrosis dynamics.

DESIGN

Multicenter cohort study.

METHODS

Fibrosis progression was defined as development of significant fibrosis [liver stiffness measurement (LSM) ≥8 kPa], or transition to cirrhosis (LSM ≥13 kPa), for those with significant fibrosis at baseline. Fibrosis regression was defined as transition to LSM less than 8 kPa, or to LSM less than 13 kPa for those with cirrhosis at baseline. MASLD was defined as hepatic steatosis (controlled attenuation parameter >248 dB/m) with at least one metabolic abnormality. A continuous-time multistate Markov model was used to describe transitions across fibrosis states.

RESULTS

Among 1183 PWH included from three centers (25.2% with viral hepatitis coinfection), baseline prevalence of significant fibrosis and MASLD was 14.4 and 46.8%, respectively. During a median follow-up of 2.5 years (interquartile range 1.9-3.5), the incidence rate of fibrosis progression and regression was 2.8 [95% confidence interval (CI) 2.3-3.4] and 2.2 (95% CI 1.9-2.6) per 100 person-years, respectively. In Markov model, weight gain increased the odds of fibrosis progression [odds ratio (OR) 3.11, 95% CI 1.59-6.08], whereas weight gain (OR 0.30, 95% CI 0.10-0.84) and male sex (OR 0.32, 95% CI 0.14-0.75) decreased the odds of fibrosis regression. On multivariable Cox regression analysis, predictors of fibrosis progression were weight gain [adjusted hazard ratio (aHR) 3.12, 95% CI 1.41-6.90] and MASLD (aHR 2.72, 95% CI 1.05-7.02).

CONCLUSION

Fibrosis transitions are driven by metabolic health variables in PWH, independently of viral hepatitis coinfection and antiretroviral class therapy.

An Electronic Health Record Model for Predicting Risk of Hepatic Fibrosis in Primary Care Patients

BACKGROUND

One challenge for primary care providers caring for patients with nonalcoholic fatty liver disease is to identify those at the highest risk for clinically significant liver disease.

AIM

To derive a risk stratification tool using variables from structured electronic health record (EHR) data for use in populations which are disproportionately affected with obesity and diabetes.

METHODS

We used data from 344 participants who underwent Fibroscan examination to measure liver fat and liver stiffness measurement [LSM]. Using two approaches, multivariable logistic regression and random forest classification, we assessed risk factors for any hepatic fibrosis (LSM > 7 kPa) and significant hepatic fibrosis (> 8 kPa). Possible predictors included data from the EHR for age, gender, diabetes, hypertension, FIB-4, body mass index (BMI), LDL, HDL, and triglycerides.

RESULTS

Of 344 patients (56.4% women), 34 had any hepatic fibrosis, and 15 significant hepatic fibrosis. Three variables (BMI, FIB-4, diabetes) were identified from both approaches. When we used variable cut-offs defined by Youden's index, the final model predicting any hepatic fibrosis had an AUC of 0.75 (95% CI 0.67-0.84), NPV of 91.5% and PPV of 40.0%. The final model with variable categories based on standard clinical thresholds (i.e., BMI ≥ 30 kg/m2; FIB-4 ≥ 1.45) had lower discriminatory ability (AUC 0.65), but higher PPV (50.0%) and similar NPV (91.3%). We observed similar findings for predicting significant hepatic fibrosis.

CONCLUSIONS

Our results demonstrate that standard thresholds for clinical risk factors/biomarkers may need to be modified for greater discriminatory ability among populations with high prevalence of obesity and diabetes.

Therapeutic implications for sphingolipid metabolism in metabolic dysfunction-associated steatohepatitis

The prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD), a leading cause of chronic liver disease, has increased worldwide along with the epidemics of obesity and related dysmetabolic conditions characterized by impaired glucose metabolism and insulin signaling, such as type 2 diabetes mellitus (T2D). MASLD can be defined as an excessive accumulation of lipid droplets in hepatocytes that occurs when the hepatic lipid metabolism is totally surpassed. This metabolic lipid inflexibility constitutes a central node in the pathogenesis of MASLD and is frequently linked to the overproduction of lipotoxic species, increased cellular stress, and mitochondrial dysfunction. A compelling body of evidence suggests that the accumulation of lipid species derived from sphingolipid metabolism, such as ceramides, contributes significantly to the structural and functional tissue damage observed in more severe grades of MASLD by triggering inflammatory and fibrogenic mechanisms. In this context, MASLD can further progress to metabolic dysfunction-associated steatohepatitis (MASH), which represents the advanced form of MASLD, and hepatic fibrosis. In this review, we discuss the role of sphingolipid species as drivers of MASH and the mechanisms involved in the disease. In addition, given the absence of approved therapies and the limited options for treating MASH, we discuss the feasibility of therapeutic strategies to protect against MASH and other severe manifestations by modulating sphingolipid metabolism.

Natural history of metabolic dysfunction-associated steatotic liver disease

Metabolic dysfunction-associated steatotic liver disease (MASLD), which has been the term for non-alcoholic fatty liver disease (NAFLD) since June 2023, represents the most common liver disease worldwide and is a leading cause of liver-related morbidity and mortality. A thorough knowledge of the disease's natural history is required to promptly stratify patients' risks, since MASLD is a multifaceted disorder with a broad range of clinical phenotypes. The histological disease spectrum ranges from isolated hepatic steatosis, currently named as metabolic dysfunction-associated steatotic liver (MASL), to metabolic dysfunction-associated steatohepatitis (MASH) and eventually may accumulate hepatic fibrosis and develop cirrhosis and/or hepatocellular carcinoma (HCC). Several risk factors for fibrosis progression have been identified, while the disease's progression displays notable dynamism and bidirectionality. When compared to the general population, all MASLD histological stages are substantially related with greater overall mortality, and this association exhibits a disease severity-dependent pattern. Interestingly, the fibrosis stage is the most accurate predictor of mortality among MASLD patients. The mortality attributed to MASLD predominantly stems from issues linked with the liver and cardiovascular system, as well as HCC and extrahepatic cancers. In light of the disease natural course, it is crucial to prioritize the identification of at-risk patients for disease progression in order to effectively address and change modifiable risk factors, hence mitigating disease complications. Further investigation is required to define the phenotype of rapid progressors more precisely as well as to improve risk stratification for HCC in non-cirrhotic individuals.

NAFLD Fibrosis Progression and Type 2 Diabetes: The Hepatic-Metabolic Interplay

The bidirectional relationship between type 2 diabetes and (non-alcoholic fatty liver disease) NAFLD is indicated by the higher prevalence and worse disease course of one condition in the presence of the other, but also by apparent beneficial effects observed in one, when the other is improved. This is partly explained by their belonging to a multisystemic disease that includes components of the metabolic syndrome and shared pathogenetic mechanisms. Throughout the progression of NAFLD to more advanced stages, complex systemic and local metabolic derangements are involved. During fibrogenesis, a significant metabolic reprogramming occurs in the hepatic stellate cells, hepatocytes, and immune cells, engaging carbohydrate and lipid pathways to support the high-energy-requiring processes. The natural history of NAFLD evolves in a variable and dynamic manner, probably due to the interaction of a variable number of modifiable (diet, physical exercise, microbiota composition, etc.) and non-modifiable (genetics, age, ethnicity, etc.) risk factors that may intervene concomitantly, or subsequently/intermittently in time. This may influence the risk (and rate) of fibrosis progression/regression. The recognition and control of the factors that determine a rapid progression of fibrosis (or its regression) are critical, as the fibrosis stages are associated with the risk of liver-related and all-cause mortality.

Endpoints in NASH Clinical Trials: Are We Blind in One Eye?

This narrative review aims to illustrate the notion that nonalcoholic steatohepatitis (NASH), recently renamed metabolic dysfunction-associated steatohepatitis (MASH), is a systemic metabolic disorder featuring both adverse hepatic and extrahepatic outcomes. In recent years, several NASH trials have failed to identify effective pharmacological treatments and, therefore, lifestyle changes are the cornerstone of therapy for NASH. with this context, we analyze the epidemiological burden of NASH and the possible pathogenetic factors involved. These include genetic factors, insulin resistance, lipotoxicity, immuno-thrombosis, oxidative stress, reprogramming of hepatic metabolism, and hypoxia, all of which eventually culminate in low-grade chronic inflammation and increased risk of fibrosis progression. The possible explanations underlying the failure of NASH trials are also accurately examined. We conclude that the high heterogeneity of NASH, resulting from variable genetic backgrounds, exposure, and responses to different metabolic stresses, susceptibility to hepatocyte lipotoxicity, and differences in repair-response, calls for personalized medicine approaches involving research on noninvasive biomarkers. Future NASH trials should aim at achieving a complete assessment of systemic determinants, modifiers, and correlates of NASH, thus adopting a more holistic and unbiased approach, notably including cardiovascular-kidney-metabolic outcomes, without restricting therapeutic perspectives to histological surrogates of liver-related outcomes alone.

A Markov model of fibrosis development in nonalcoholic fatty liver disease predicts fibrosis progression in clinical cohorts

Disease progression in nonalcoholic steatohepatitis (NASH) is highly heterogenous and remains poorly understood. Fibrosis stage is currently the best predictor for development of end-stage liver disease and mortality. Better understanding and quantifying the impact of factors affecting NASH and fibrosis is essential to inform a clinical study design. We developed a population Markov model to describe the transition probability between fibrosis stages and mortality using a unique clinical nonalcoholic fatty liver disease cohort with serial biopsies over 3 decades. We evaluated covariate effects on all model parameters and performed clinical trial simulations to predict the fibrosis progression rate for external clinical cohorts. All parameters were estimated with good precision. Age and diagnosis of type 2 diabetes (T2D) were found to be significant predictors in the model. Increase in hepatic steatosis between visits was the most important predictor for progression of fibrosis. Fibrosis progression rate (FPR) was twofold higher for fibrosis stages 0 and 1 (F0-1) compared to fibrosis stage 2 and 3 (F2-3). A twofold increase in FPR was observed for T2D. A two-point steatosis worsening increased the FPR 11-fold. Predicted fibrosis progression was in good agreement with data from external clinical cohorts. Our fibrosis progression model shows that patient selection, particularly initial fibrosis stage distribution, can significantly impact fibrosis progression and as such the window for assessing drug efficacy in clinical trials. Our work highlights the increase in hepatic steatosis as the most important factor in increasing FPR, emphasizing the importance of well-defined lifestyle advise for reducing variability in NASH progression during clinical trials.

FIB-4 is closer to FibroScan screen results to detecting advanced liver fibrosis and maybe facilitates NAFLD warning

To assess the relationship between clinical biochemical characteristics and steatosis or fibrosis by Fibroscan in non-alcoholic fatty liver disease (NAFLD) patients in order to seek the simple effective screening method closed to the results of the fibroScan measurement. A cross-sectional study was conducted on 188 patients with NAFLD who underwent FibroScan examinations. Demographic data and clinical biochemical characteristics were collected and analyzed. The result showed elevated serum uric acid (SUA) (P = .023, odds ratio [OR = 1.005, 95% CI (1.001-1.009) and metabolic syndrome (MetS) (P = .000, OR = 4.549, 95%CI (1.974-10.484) were associated with severe steatosis (controlled attenuation parameter, CAP ≥ 300 dB/m). The magnitude of liver stiffness measured using FibroScan was positively correlated with aspartate transaminase/alanine aminotransferase (AST/ALT) ratio (R = 0.419, P = .000), AST to platelet ratio index (APRI) score (R = 0.309, P = .000), and Fibrosis-4 score (FIB-4) (R = 0.507, P = .000). The areas under the receiver operating curve (ROC) of AST/ALT, APRI, and FIB-4 for mild or severe fibrosis were 0.563, 0.696, and 0.728, respectively, and those for advanced fibrosis were 0.648, 0.750, and 0.821, respectively. The FIB-4 index cutoff value was 1.65 with a sensitivity of 68.3% and specificity of 89.8% during the diagnosis of advanced fibrosis. MetS and elevated SUA are associated with severe steatosis according to the CAP value screen, whereas FIB-4, as the fibrosis score method, is closer to the liver stiffness measurement results from FibroScan, which may facilitate early warning of NAFLD in the community or in remote areas.

Non-invasive biomarkers for liver inflammation in non-alcoholic fatty liver disease: present and future

Inflammation is the key driver of liver fibrosis progression in non-alcoholic fatty liver disease (NAFLD). Unfortunately, it is often challenging to assess inflammation in NAFLD due to its dynamic nature and poor correlation with liver biochemical markers. Liver histology keeps its role as the standard tool, yet it is well-known for substantial sampling, intraobserver, and interobserver variability. Serum proinflammatory cytokines and apoptotic markers, namely cytokeratin-18, are well-studied with reasonable accuracy, whereas serum metabolomics and lipidomics have been adopted in some commercially available diagnostic models. Ultrasound and computed tomography imaging techniques are attractive due to their wide availability; yet their accuracies may not be comparable with magnetic resonance imaging-based tools. Machine learning and deep learning models, be they supervised or unsupervised learning, are promising tools to identify various subtypes of NAFLD, including those with dominating liver inflammation, contributing to sustainable care pathways for NAFLD.