Exploring the landscape of steatotic liver disease in the general US population

Disease classification, diagnostic challenges, and evolving clinical trial design in MASLD

Metabolic dysfunction-associated steatotic liver disease (MASLD) diagnosis and management have evolved rapidly alongside the increasing prevalence of obesity and related complications. Hepatology has expanded its focus beyond late-stage cirrhosis and portal hypertension to earlier, complex MASLD cases in younger patients, necessitating closer collaboration with endocrinology. The renaming of nonalcoholic fatty liver disease (NAFLD) to MASLD reflects its pathophysiology, reduces stigma, and has prompted new research directions. Noninvasive tests such as liver stiffness measurement now play a crucial role in diagnosis, reducing reliance on invasive liver biopsies. However, advanced omics technologies, despite their potential to enhance diagnostic precision and patient stratification, remain underutilized in routine clinical practice. Behavioral factors, including posttraumatic stress disorder (PTSD) and lifestyle choices, influence disease outcomes and must be integrated into patient management strategies. Primary care settings are critical for early screening to prevent progression to advanced disease, yet sizable challenges remain in implementing effective screening protocols. This Review explores these evolving aspects of MASLD diagnosis and management, emphasizing the need for improved diagnostic tools, multidisciplinary collaboration, and holistic care approaches to address existing gaps and ensure comprehensive patient care across all healthcare levels.

Clinical characteristics of MASLD/MetALD/MAFLD/NAFLD and the relative risk analysis on metabolic disorders

OBJECTIVES

Our objective was to compare the clinical features of Metabolic dysfunction-associated steatotic liver disease (MASLD) /metabolic alcohol-related liver disease (MetALD)/metabolic associated fatty liver disease (MAFLD)/nonalcoholic fatty liver disease (NAFLD) and the relative risk analysis of metabolic disorders.

METHODS

The National Health and Nutrition Examination Survey for the 2017-2018 cycle was used to screen the participants. Multivariate-adjusted logistic regression models were applied to explore the difference in relative risk analysis between NAFLD/MAFLD/MASLD/MetALD and metabolic disorders.

RESULTS

Among the 1,862 eligible individuals, 358(44.84%) had MASLD, 213(11.44%) had MetALD, 841(45.17%) had MAFLD, and 1,125(60.42%) had NAFLD. Positive associations with the risk of hypertension were discovered for MASLD (OR = 2.892, 95%CI = 2.226-3.756), MetALD (OR = 1.802, 95% CI = 1.355-2.398), MAFLD (OR = 3.455, 95%CI = 2.741-4.354) and NAFLD (OR = 1.983, 95%CI = 1.584-2.484). Positive associations with the risk of T2DM were discovered for MASLD (OR = 6.360, 95%CI = 4.440-9.109), MAFLD (OR = 7.026, 95%CI = 4.893-10.090) and NAFLD (OR = 3.372, 95%CI = 2.511-4.528). We discovered similar results for hyperlipidemia. Compared to mild steatosis, moderate to severe steatosis in patients with MASLD (OR = 3.924, 95%CI = 2.399-6.419), MAFLD (OR = 3.814, 95%CI = 2.367-6.144), NAFLD (OR = 4.910, 95%CI = 2.983-8.080) has a higher risk for T2DM.

CONCLUSION

The proposed definitions of MASLD and MetALD are valuable and deserve further exploration. Our findings suggest that MAFLD is a more effective indicator for identifying patients at increased risk for metabolic disorders.

Prevalence and Predictors of Suspected Metabolic Dysfunction-Associated Steatotic Liver Disease in Adolescents in the United States

BACKGROUND

Nomenclature for steatotic liver disease has been updated to include metabolic dysfunction-associated steatotic liver disease (MASLD), which requires the presence of hepatic steatosis and at least one cardiometabolic risk factor. The prevalence of MASLD in adolescents is understudied.

AIM

To determine the prevalence of suspected MASLD among adolescents in the United States and to examine the relationships between elevated alanine aminotransferase (ALT) and cardiometabolic risk factors.

METHODS

A cross-sectional analysis of the National Health and Nutrition Examination Survey from 2011 to 2020 was conducted for adolescents aged 12-19 years. Elevated ALT was defined using sex-specific biological upper limits: > 26 U/L for males and > 22 U/L for females. Suspected MASLD was identified by elevated ALT and at least one cardiometabolic risk factor. Adolescents with elevated ALT were categorised as having suspected MASLD, elevated ALT due to other causes or cryptogenic ALT elevation.

RESULTS

Overall, 14.6% of adolescents had elevated ALT. Of these, 77.2% had suspected MASLD, 20.2% had cryptogenic ALT elevation, 1.9% took hepatotoxic medications and 0.7% had viral hepatitis. Body mass index had the strongest association with elevated ALT (OR 3.55), followed by high triglycerides (OR 2.09), low HDL cholesterol (OR 2.05) and high blood pressure (OR 1.93).

CONCLUSIONS

Most adolescents with elevated ALT met MASLD criteria, yet a portion lacked cardiometabolic risk factors or other identifiable causes. These results support the adoption of MASLD criteria in adolescents while indicating a need for further research into cryptogenic ALT elevation in paediatric populations.

New steatotic liver disease criteria diagnostic performance in an agricultural population in Chile

INTRODUCTION AND OBJECTIVES

This study aims to assess the performance of Steatotic Liver Disease (SLD) criteria in identifying liver steatosis compared to the NAFLD and MAFLD definitions in an agricultural population in Chile.

PATIENTS AND METHODS

We performed a cross-sectional analysis on the MAUCO cohort, composed of 9,013 individuals aged 38 to 74. Health conditions, socio-demographics, anthropometrics, hepatic ultrasonography, blood pressure, and biological samples were obtained. Participants were classified as NAFLD, MAFLD, or any of the five SLD categories: Metabolic dysfunction-associated steatosis liver disease (MASLD), Metabolic and Alcohol-Associated Liver Disease (MetALD), Alcohol-Associated Liver Disease (ALD), Specific aetiologies, and Cryptogenic. The Framingham cardiovascular risk score and BARD liver fibrosis score were used to assess clinical relevance.

RESULTS

Liver steatosis was present in 4,082 participants (45%); SLD criteria captured an additional 176 individuals not classified under NAFLD and 103 not included under MAFLD definition. The main SLD subgroups were MASLD (95%), MetALD (1.9%) and ALD (1.3%). Individuals classified in the MetALD and ALD subgroups exhibited more severe liver steatosis and a higher cardiovascular risk. Notably, participants categorized under specific etiologies and cryptogenic subgroups were younger and had a higher risk for liver fibrosis.

CONCLUSIONS

The study reveals that SLD offers a more inclusive classification to identify high-risk individuals in the Chilean population, capturing cases that could be missed by NAFLD or MAFLD definitions by using the same resources.

MAFLD vs. MASLD: a year in review

INTRODUCTION

In 2023, metabolic dysfunction-associated steatotic liver disease (MASLD) was introduced following metabolic dysfunction-associated fatty liver disease (MAFLD). Both aim to address the limitations of nonalcoholic fatty liver disease (NAFLD). This review analyzes the similarities and differences between MAFLD and MASLD, focusing on their impacts on epidemiology, diagnosis, stigma, and related liver diseases.

AREAS COVERED

Current evidence suggests that MAFLD criteria effectively identify individuals at higher risk through a good balance of sensitivity and specificity. Moreover, MAFLD is a more generalizable term that is easily understood globally.

EXPERT OPINION

The transition from NAFLD to MAFLD and MASLD marks a significant advance in understanding fatty liver disease within hepatology. MAFLD identifies a homogeneous cohort of patients with fatty liver due to metabolic dysfunction and provides a valuable framework for holistic, patient-centered management strategies that consider various contributing factors to improve health outcomes.

Possible link between steatotic liver diseases, severe COVID-19 and cognitive impairment in post-COVID-19 syndrome

PURPOSE

Steatotic liver diseases (SLD) have become more prevalent over the last decade and are associated not only with cardiometabolic diseases but also with psychological symptoms (depression, fatigue). These symptoms are also common in post-COVID syndrome (PCS). Therefore, the aim of the study was to analyze the burden of SLD in PCS patients.

METHODS

We systematically screened all PCS patients from our post-COVID outpatient clinic using transient elastography, structured questionnaires for neurocognitive evaluation and blood sample analysis. Controls without PCS and without known liver diseases were also recruited and assessed with the same approach.

RESULTS

560 PCS patients and 103 healthy controls were included. The overall prevalence of SLD was high in both cohorts (57 vs. 53%). PCS patients with SLD were more frequently male (41 vs. 24%), older (52 vs. 44 years) and had more cardiometabolic diseases (87.0 vs. 46.4%). Cognitive impairment was more related to SLD in PCS patients than in the no-SLD group (OR: 1.68, CI: 1.14-2.46, p = 0.008). The presence of SLD was related to severe COVID-19 with hospitalization (OR: 2.91, CI: 1.85-4.56, p < 0.001). Within 1 year of the follow-up, 152 of 289 patients described a resolution in PCS irrespective of the presence or absence of SLD (log-rank p = 0.96).

CONCLUSIONS

SLD is associated with severe COVID-19 and cognitive dysfunction in PCS. Longitudinal studies are needed to assess the role of hepatic steatosis, development of post-acute infection regulation (e.g., SARS-CoV-2) and to differentiate between SLD-associated symptoms and PCS.

Association between MASLD and increased risk of serious bacterial infections requiring hospital admission: A meta-analysis

BACKGROUND

Previous studies have reported an association between metabolic dysfunction-associated steatotic liver disease (MASLD) and the risk of serious bacterial infections. However, the magnitude of the risk and whether this risk varies with the severity of MASLD remains uncertain. We performed a meta-analysis of observational studies to quantify the association between MASLD and serious bacterial infections requiring hospital admission.

METHODS

We systematically searched PubMed, Scopus, Web of Science and Embase from database inception to 1 April 2024, using predefined keywords to identify studies examining the risk of serious bacterial infections among individuals with and without MASLD. MASLD was diagnosed using liver biopsy, imaging or International Classification of Diseases codes. Meta-analysis was performed using random-effects modelling.

RESULTS

We identified six cross-sectional and two prospective cohort studies with aggregate data on ~26.6 million individuals. MASLD was significantly associated with higher odds of serious bacterial infections (pooled random-effects odds ratio 1.93, 95% confidence interval [CI] 1.44-2.58; I2 = 93%). Meta-analysis of prospective cohort studies showed that MAFLD was associated with an increased risk of developing serious bacterial infections (pooled random-effects hazard ratio 1.80, 95% CI 1.62-2.0; I2 = 89%). This risk further increased across the severity of MASLD, especially the severity of fibrosis (pooled random-effects hazard ratio 2.42, 95% CI 1.89-2.29; I2 = 92%). These results remained significant after adjusting for age, sex, obesity, diabetes and other potential confounders. Sensitivity analyses did not modify these findings. The funnel plot did not reveal any significant publication bias.

CONCLUSIONS

This meta-analysis shows a significant association between MASLD and an increased risk of serious bacterial infections requiring hospital admission.

Current burden of steatotic liver disease and fibrosis among adults in the United States, 2017-2023

BACKGROUND/AIMS

Multi-society experts proposed the adoption of new terminology, metabolic dysfunctionassociated steatotic liver disease (MASLD) and steatotic liver disease (SLD). We studied the current prevalence of SLD and its subcategories in the US.

METHODS

Using the recent National Health and Nutrition Examination Survey from 2017 to 2023, we analyzed data from 12,199 participants (≥18 years) who completed transient elastography. SLD and its subcategories, including MASLD, metabolic and alcohol-related liver disease (MetALD), and alcohol-related liver disease (ALD), were categorized according to consensus nomenclature.

RESULTS

The age-adjusted prevalence of SLD (cut-off: 285 dB/m) was 35.0% (95% confidence interval [CI] 33.4-36.7). Within this category, the age-adjusted prevalence for MASLD was 31.9% (95% CI 30.4-33.4), MetALD 2.2% (95% CI 1.8-2.6), and ALD 0.8% (95% CI 0.6-1.1). The prevalence of SLD and MASLD showed a statistically insignificant decrease during COVID-19, while ALD increased without significance. In contrast, the prevalence of advanced fibrosis in SLD was significantly higher during the COVID-19 era, at 9.8% for 285 dB/m and 7.8% for 263 dB/m, compared to 7.4% (P=0.039) and 6% (P=0.041) in the pre-COVID-19 era. The proportion of advanced fibrosis and cirrhosis in individuals with ALD was two-fold higher than MASLD and MetALD, largely due to increases during the COVID-19 era.

CONCLUSION

While the prevalence of SLD and its subcategories remained stable, there was a significant increase in advanced fibrosis among SLD individuals during the COVID-19 era, with ALD having a proportion of advanced fibrosis and cirrhosis that was twice as high as MASLD and MetALD.

Metabolic dysfunction and alcohol-related liver disease (MetALD): Position statement by an expert panel on alcohol-related liver disease

In this position statement, we explore the intricate relationship between alcohol intake and metabolic dysfunction in the context of the 2023 nomenclature update for steatotic liver disease (SLD). Recent and lifetime alcohol use should be accurately assessed in all patients with SLD to facilitate classification of alcohol use in grams of alcohol per week. Alcohol biomarkers (i.e., phosphatidylethanol), use of validated questionnaires (i.e. AUDIT-C [alcohol use disorders identification test consumption]), and collateral information from friends and relatives could help facilitate differentiation between alcohol-related liver disease (ALD) per se and liver disease with both metabolic and alcohol-related components (MetALD). Heavy alcohol use can contribute to cardiometabolic risk factors such as high blood pressure, hypertriglyceridaemia, and hyperglycaemia. As a result, caution should be exercised in the application of only one metabolic dysfunction criterion to diagnose MASLD, as suggested in the 2023 nomenclature document, particularly in individuals exceeding weekly alcohol use thresholds of 140 g for women and 210 g for men. This is particularly important in those individuals with isolated high blood pressure, hypertriglyceridaemia, or hyperglycaemia, where the disease process may be driven by alcohol itself. Additionally, metabolic dysfunction and alcohol use should be reassessed over time, especially after periods of change in risk factor exposure. This approach could ensure a more accurate prognosis and effective management of SLD, addressing both metabolic and alcohol-related factors.

Exploring the potential of large language models in identifying metabolic dysfunction-associated steatotic liver disease: A comparative study of non-invasive tests and artificial intelligence-generated responses

BACKGROUND AND AIMS

This study sought to assess the capabilities of large language models (LLMs) in identifying clinically significant metabolic dysfunction-associated steatotic liver disease (MASLD).

METHODS

We included individuals from NHANES 2017-2018. The validity and reliability of MASLD diagnosis by GPT-3.5 and GPT-4 were quantitatively examined and compared with those of the Fatty Liver Index (FLI) and United States FLI (USFLI). A receiver operating characteristic curve was conducted to assess the accuracy of MASLD diagnosis via different scoring systems. Additionally, GPT-4V's potential in clinical diagnosis using ultrasound images from MASLD patients was evaluated to provide assessments of LLM capabilities in both textual and visual data interpretation.

RESULTS

GPT-4 demonstrated comparable performance in MASLD diagnosis to FLI and USFLI with the AUROC values of .831 (95% CI .796-.867), .817 (95% CI .797-.837) and .827 (95% CI .807-.848), respectively. GPT-4 exhibited a trend of enhanced accuracy, clinical relevance and efficiency compared to GPT-3.5 based on clinician evaluation. Additionally, Pearson's r values between GPT-4 and FLI, as well as USFLI, were .718 and .695, respectively, indicating robust and moderate correlations. Moreover, GPT-4V showed potential in understanding characteristics from hepatic ultrasound imaging but exhibited limited interpretive accuracy in diagnosing MASLD compared to skilled radiologists.

CONCLUSIONS

GPT-4 achieved performance comparable to traditional risk scores in diagnosing MASLD and exhibited improved convenience, versatility and the capacity to offer user-friendly outputs. The integration of GPT-4V highlights the capacities of LLMs in handling both textual and visual medical data, reinforcing their expansive utility in healthcare practice.

Diagnosis and Management of Early Stages of ALD

Early forms of alcohol-associated liver disease (ALD) include different stages in the progression of compensated liver disease ranging from steatosis to steatohepatitis and fibrosis. ALD has been classically diagnosed at advanced stages more frequently than other liver diseases. This fact probably contributed to the scarcity of studies on early forms of ALD. Recent studies have investigated the prevalence of early ALD in the general population and have described the natural history of alcohol-induced steatosis and fibrosis, which have been linked to worse prognosis compared with early stages of other chronic liver diseases. In addition, studies on screening and early diagnosis of ALD in at-risk populations have shown that these strategies allow early detection and intervention. Of note, up to 28% of the United States population has concurrent alcohol use and metabolic syndrome, and estimated prevalence of advanced fibrosis among heavy drinkers with metabolic syndrome has increased from 3% in the 1990s to more than 10% in the 2010s. Therefore, new challenges and treatment opportunities will emerge for patients with ALD. In this review, we provide an overview of the state of the art in early ALD, focusing on natural history, diagnosis, and management, and provide insights into future perspectives.

Metabolic-Dysfunction-Associated Steatotic Liver Disease: Molecular Mechanisms, Clinical Implications, and Emerging Therapeutic Strategies

Metabolic-dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease (NAFLD), is a highly prevalent metabolic disorder characterized by hepatic steatosis in conjunction with at least one cardiometabolic risk factor, such as obesity, type 2 diabetes, hypertension, or dyslipidemia. As global rates of obesity and metabolic syndrome continue to rise, MASLD is becoming a major public health concern, with projections indicating a substantial increase in prevalence over the coming decades. The disease spectrum ranges from simple steatosis to metabolic-dysfunction-associated steatohepatitis (MASH), fibrosis, cirrhosis, and hepatocellular carcinoma, contributing to significant morbidity and mortality worldwide. This review delves into the molecular mechanisms driving MASLD pathogenesis, including dysregulation of lipid metabolism, chronic inflammation, oxidative stress, mitochondrial dysfunction, and gut microbiota alterations. Recent advances in research have highlighted the role of genetic and epigenetic factors in disease progression, as well as novel therapeutic targets such as peroxisome proliferator-activated receptors (PPARs), fibroblast growth factors, and thyroid hormone receptor beta agonists. Given the multifaceted nature of MASLD, a multidisciplinary approach integrating early diagnosis, molecular insights, lifestyle interventions, and personalized therapies is critical. This review underscores the urgent need for continued research into innovative treatment strategies and precision medicine approaches to halt MASLD progression and improve patient outcomes.

Overlap prevalence and interaction effect of cardiometabolic risk factors for metabolic dysfunction-associated steatotic liver disease

BACKGROUND

Cardiometabolic risk factors (CMRFs) related to metabolic dysfunction-associated steatotic liver disease (MASLD) comprised overweight/obesity, impaired glucose metabolism, hypertension, hypertriglyceridemia and low high-density lipoprotein cholesterol. We aimed to describe the overlap prevalence and synergistic interaction of the five CMRFs on MASLD and liver fibrosis.

METHODS

Using data of 2017-2020 National Health and Nutrition Examination Survey, we included non-pregnant participants aged ≥ 20 years who completed vibration-controlled transient elastography examinations and had sufficient information to determine their metabolic status. Logistic and generalized linear regression models were performed to assess synergistic interaction between CMRFs on MASLD and identify the contributions to liver fibrosis.

RESULTS

The overall estimated prevalence of MASLD was about 33.1%. More than 80% of patients had three or more CMRFs. For MASLD, synergistic interaction between pairs of overweight/obesity and other four CMRFs were higher than it between other CMRFs' pairs [attributable proportion(AP): 40-50% vs 20-30%]. For liver fibrosis, overweight/obesity and impaired glucose metabolism or hypertension had significant synergistic interactions (AP: 50% or 30%, respectively). We identified 27 out of 31 possible CMRF combinations. Combinations including dyslipidemia were more frequent in men than women (77% vs 59%). Combinations including hypertension were less in Mexican Americans than other ethnicities (25% vs 45-57%). Most combinations with three or more CMRFs, regardless of overlap type, had significant associations with elevated liver stiffness value.

CONCLUSIONS

CMRF overlap was quite common and had additive interaction in patients with MASLD. Overlapping number may be more important than combination type in liver fibrosis development.

Clinical Variables that Predict Liver-related Events in Steatotic Liver Disease Diagnosed by a Liver Biopsy

Objective Identifying patients at high risk of steatotic liver disease (SLD) is crucial. The liver fibrosis stage is the most reliable marker of liver-related mortality. However, noninvasive risk stratification methods remain controversial. Therefore, we analyzed the risk of liver-related events in patients who underwent a liver biopsy for metabolic dysfunction-associated steatotic liver disease (MASLD) or cryptogenic SLD at our hospital. Methods We retrospectively reviewed the clinical course of the patients to identify the occurrence of liver-related events. Patients This study included 146 patients diagnosed with SLD through a liver biopsy. Results Liver-related events occurred in 20 patients and were more frequent in those with advanced fibrosis than in those without advanced fibrosis. However, patients with advanced steatosis exhibit reduced disease progression. Patients with obesity and/or diabetes complications had a lower stage of fibrosis and better prognosis than the others. The non-invasive fibrosis-4 (FIB-4) index and non-alcoholic fatty liver disease (NAFLD) prognosis-related "NAFLD outcomes score (NOS)" effectively differentiated patients with disease progression. Standard laboratory data analyses revealed that high total bilirubin and low albumin levels were risk factors. A multivariate analysis with significant factors other than NOS score revealed that the absence of obesity and/or diabetes complications, a high FIB-4 index, and a high total bilirubin level were independent factors for liver-related events. Conclusion A high NOS score, absence of obesity and/or diabetes complications, a high FIB-4 index, and high total bilirubin levels are risk factors for disease progression. Patients with lean phenotypes or non-diabetic SLD should also be assessed using noninvasive markers to determine their risks and potential outcomes.

Prevalence, characteristics and outcomes of patients with metabolic and alcohol related/associated liver disease (MetALD): a systematic review and meta-analysis

BACKGROUND

In light of the new nomenclature of steatotic liver disease (SLD), we aimed to enhance the existing knowledge on the epidemiology and clinical outcomes of metabolic and alcohol related/associated liver disease (MetALD).

METHODS

A systematic review and meta-analysis were performed in Medline/PubMed, Embase, Scopus and Cochrane databases to evaluate the prevalence and outcomes of MetALD within the SLD population and to compare the characteristics between MetALD patients and those with metabolic dysfunction associated steatotic liver disease (MASLD) and alcohol-related liver disease (ALD). Nineteen studies from nine countries that evaluated 4,543,341 adult participants with SLD were included.

RESULTS

The pooled overall prevalence of MetALD among the SLD population was 10 % (95%CI:7-13 %) without significant difference between Asian and non-Asian populations. However, MetALD was more frequent in men than women (86 % vs 14 %, p < 0.01), while Asian MetALD patients, were more frequent men (92 % vs 66 %, p < 0.01) compared to non-Asians. Additionally, in terms of metabolic characteristics there were no significant differences between MetALD, MASLD and ALD patients. Regarding outcomes, patients with MetALD, compared to non-SLD, were at increased risk of all-cause [HR 1.44 (95%CI:1.24-1.66)], cardiovascular disease (CVD) [HR 1.17 (95%CI:1.12-1.21)] and cancer-related mortality [HR 2.07 (95%CI:1.32-3.25)]. Finally, patients with MetALD, had increased incidence of CVD and liver decompensating events, compared to non-SLD participants [HR 1.49 (95%CI:1.03-2.15); HR 10.55 (95%CI:3.46-32.16) respectively].

CONCLUSIONS

Based on the existing literature, patients with MetALD consist a significant part of the SLD population, with high all-cause, CVD and cancer-related mortality and increased risk for CVD and hepatic decompensation.

Factors Associated with Nonalcoholic Fatty Liver Disease in a Non-Overweight/Obese and Overweight/Obese Chinese Population at Risk for Metabolic Syndrome: A Cross-Sectional Multicenter Study

Background: To investigate the association of demographic, clinical, and metabolic factors with nonalcoholic fatty liver disease (NAFLD) in a non-overweight/obese and overweight/obese Chinese population at risk for metabolic syndrome. Patients and Method: A cross-sectional multicenter study was conducted using convenience sampling from eight selected counties/cities in Zhejiang, China, between May 2021 and September 2022. Demographics, epidemiological, anthropometric, and clinical characteristics were obtained from a questionnaire. Least absolute shrinkage and selection operator (LASSO)-logistic regression analysis was used to identify the variables associated with NAFLD. Receiver operating characteristic (ROC) curve analysis and decision curve analysis (DCA) were performed to evaluate the diagnostic value and clinical utility of the variables and models. Results: A total of 1739 patients were enrolled in the final analysis, 345 (19.8%) were non-overweight/obese and 1394 (80.2%) were overweight/obese participants. There were 114 (33.0%) and 1094 (78.5%) patients who met the criteria for NAFLD in the non-overweight/obese participants and the overweight/obese participants respectively. Older age, current smoking, higher triglyceride (TG) levels, higher AST levels, higher albumin levels, lower insulin levels, and higher controlled attenuation parameter (CAP) scores were associated with NAFLD in both non-overweight/obese and overweight/obese participants. The combination of TG+CAP scores had strong predictive values for NAFLD, especially in non-overweight/obese (Area Under Curve = 0.812, 95% confidence interval: 0.764-0.863). DCA showed a superior net benefit of the TG+CAP score over other variables or models, suggesting a better clinical utility in identifying NAFLD. Conclusions: More stringent lipid management strategies remain essential, and the convenience and efficacy of transient elastography for liver steatosis should be recognized, especially in the non-overweight/obese population.

MetALD: Clinical aspects, pathophysiology and treatment

Metabolic dysfunction-associated steatotic liver disease (MASLD) and alcohol-related liver disease (ALD) are the most prevalent causes of chronic liver disease worldwide. Both conditions have many pathophysiological mechanisms in common, such as altered lipid and bile acid metabolism, and share some similar clinical features. Furthermore, metabolic risk factors and alcohol often co-exist in the same individuals and have recently been shown to act synergistically to markedly increase the risk of liver disease. Given the high prevalence and impact of this interaction, steatotic liver disease due to the combination of metabolic dysfunction and moderate-to-high alcohol intake has been termed MetALD in the new steatotic liver disease nomenclature, attracting the interest of the scientific community. Subsequent studies have investigated the prevalence of MetALD, which ranges from 1.7% to 17% in cohorts of patients with steatotic liver disease, depending on the population setting and study design. A few cohort studies have also assessed the prognosis of this patient population, with preliminary data suggesting that MetALD is associated with an intermediate risk of liver fibrosis, decompensation and mortality among steatotic liver disease subtypes. In this review article, we examine the clinical evidence and the experimental models of MetALD and discuss the clinical implications of the term for early detection and management. We provide insight into the pathophysiological mechanisms of the synergistic effect of alcohol and metabolic risk factors, possible screening strategies, the use of biomarkers and emerging models of care, as well as potential therapeutic interventions with a special focus on medications for MASLD, highlighting the most promising drugs for patients with MetALD.

Metabolic dysfunction-associated steatotic liver disease: A pathophysiology and clinical framework to face the present and the future

AIMS

This review aims to provide a straightforward conceptual framework for the knowledge and understanding of Metabolic dysfunction-associated steatotic liver disease (MASLD) in the broad spectrum of steatotic liver disease and to point out the need to consider metabolic dysfunction and comorbidities as interrelated factors for a holistic approach to fatty liver disease.

DATA SYNTHESIS

MASLD is the new proposed term for steatotic liver disease that replaces the old terminology of non-alcoholic fatty liver disease. This term focused on the relationship between metabolic alteration and hepatic steatosis, reflecting a growing comprehension of the association between metabolic dysfunction and hepatic steatosis. Numerous factors and conditions contribute to the underlying mechanisms, including central obesity, insulin resistance, adiponectin, lipid metabolism, liver function, dietary influences, the composition of intestinal microbiota, and genetic factors. The development of the condition, however, involves a more intricate network of components, such as neurotensin and Advanced Glycation End Products, highlighting the complexity of its pathogenesis.

CONCLUSIONS

MASLD must be regarded as a complex clinical problem in which only a holistic approach can win through the coordination of multi-professional and multi-speciality interventions.

Diet quality and physical activity affect metabolic dysfunction-associated steatotic liver disease, metabolic dysfunction and etiology-associated steatohepatitis, and compensated advanced chronic liver disease among United States adults: NHANES 2017-2020

Background and aim

Clinical data on the prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction and etiology-associated steatohepatitis (MetALD) in a multi-ethnic U.S. population are limited. Additionally, the impact of physical activity (PA) and diet quality (DQ) on the risk of MASLD, MetALD, and compensated advanced chronic liver disease (cACLD) remains unclear. This study aimed to investigate the associations of PA and diet quality with the risks of MASLD, MetALD, and cACLD.

Methods and results

This cross-sectional study analyzed data from 7,125 participants in the National Health and Nutrition Examination Survey (NHANES) 2017-2020. Diet quality was assessed using the Healthy Eating Index-2015 (HEI-2015). PA was assessed based on the 2020 WHO Physical Activity Guidelines, with participants reporting the intensity, frequency, and duration of their activities over the past 7 days. MASLD and MetALD were diagnosed based on clinical criteria, and cACLD was defined by advanced liver fibrosis. Bivariate and multivariable logistic regression models were used to assess associations between PA, diet quality, and liver disease outcomes. The prevalence of MASLD and MetALD was 35.07 and 21.46%, respectively. HQD was associated with significantly lower risks of MASLD (OR: 0.49, 95% CI: 0.38-0.62) and MetALD (OR: 0.45, 95% CI: 0.36-0.56). High PA levels were linked to reduced risks of MASLD (OR: 0.47, 95% CI: 0.38-0.58) and MetALD (OR: 0.53, 95% CI: 0.39-0.72). The lowest risks for both MASLD and MetALD were observed in highly active participants with an HQD (MASLD OR: 0.41, 95% CI: 0.32-0.53; MetALD OR: 0.54, 95% CI: 0.41-0.71). Significant interactions were observed between PA, HQD, and age, BMI, and SES, which further reduced the risks of MASLD and MetALD. For cACLD, both increased PA and HQD were associated with reduced risk. Compared to non-high-activity participants with a non-HQD, physically active participants with an HQD had the lowest risk of cACLD (OR: 0.44, 95% CI: 0.24-0.82).

Conclusion

High proportions of the US population have MASLD or MetALD. HQD and high PA levels were associated with lower risks of MASLD, MetALD, and cACLD.

Dietary Patterns Rich in Soybean Products, Vegetables, Fish, Fruits, and Miso Soup Were Inversely Associated with Fatty Liver Index: The Nagahama Study

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a prominent liver disease occurring in approximately 25% of the general population. As treatment, lifestyle modification is essential, but there are few reports on dietary patterns associated with MASLD except for the Mediterranean diet. This study examines dietary habits related to MASLD using the fatty liver index (FLI). Longitudinal analysis of a community-based cohort, the Nagahama Prospective Cohort for Comprehensive Human Bioscience, was performed. Dietary habits were assessed by a self-reported questionnaire on food intake frequency, and factor analysis was applied to identify dietary patterns. Multiple regression analysis was performed with baseline FLI or FLI after 5 y as the dependent variable and sex, age, and/or baseline FLI, and factor scores of each dietary pattern as simultaneous independent variables. The same analyses stratified by sex or body mass index (BMI) were also performed. Three thousand five hundred one participants were included. The 15 food items of the questionnaire were summarized into four dietary patterns. Dietary patterns rich in soybean products, vegetables, fish, fruits, and miso soup, which is characteristic of traditional Japanese diet, negatively correlated with FLI and FLI after 5 y (partial regression coefficient: -3.01 and -1.03, respectively; p<0.01 for both). The result was similar in sex-specific analysis and in BMI<23 kg/m2 group, when the participants were stratified according to BMI. Our results suggest that dietary patterns rich in soybean products, vegetables, fish, fruits, and miso soup are protective factors against MASLD especially in individuals with BMI<23 kg/m2.

Prevalence of metabolic dysfunction-associated steatotic liver disease and fibrosis defined by liver elastography in the United States using National Health and Nutrition Examination Survey 2017-March 2020 and August 2021-August 2023 data

BACKGROUND AND AIMS

Steatotic liver disease (SLD) is a significant public health burden. Previously, we estimated prepandemic SLD prevalence determined by transient elastography-assessed hepatic steatosis and fibrosis in the United States. We now estimate the prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) and examine associations with lifestyle, socioeconomic, and other factors.

APPROACH AND RESULTS

Liver stiffness and controlled attenuation parameters were assessed on 13,538 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 2017 to March 2020 and August 2021 to August 2023. The prevalence of SLD (controlled attenuation parameter >300 dB/m) was 28.7%, fibrosis (liver stiffness >8 kPa) was 11.3%, and MASLD was 25.6%. Between the 2 survey cycles, the age-standardized SLD prevalence was not significantly different, MASLD prevalence decreased (26.8%-23.6%), and fibrosis prevalence increased (10.4%-12.7%). In multivariable-adjusted analysis, both MASLD and fibrosis were associated with diabetes, higher body mass index, higher waist-to-hip ratio, elevated blood pressure, and inversely associated with non-Hispanic Black race-ethnicity. MASLD was also associated with male sex, non-Hispanic Asian race-ethnicity, prediabetes, higher total cholesterol, lower HDL cholesterol, and greater sedentary lifestyle. Fibrosis was also associated with SLD, lower total cholesterol, and less education.

CONCLUSIONS

In the US population, MASLD and fibrosis prevalence are high along with obesity and diabetes. Our findings suggest that early detection of chronic liver disease and targeting lifestyle and other modifiable risk factors may slow disease progression toward advanced fibrosis and cirrhosis.

Association of life's essential 8 with all-cause and cause-specific mortality in metabolic dysfunction-associated steatotic liver disease

The American Heart Association has updated the cardiovascular health (CVH) assessment tool, referred to as the Life's Essential 8 (LE8). Metabolic dysfunction-associated steatotic liver disease (MASLD) is now the most common chronic liver disease worldwide and is linked to an elevated risk of mortality. We aimed to explore the association of LE8 with all cause and cause-specific mortality in MASLD in a prospective cohort study. A total of 10,050 participants with MASLD from the NHANES 2005-2018 dataset were included in the study. LE8 was evaluated by combining four health behaviors and four health factors, with scores of 0-49 categorized as low CVH, 50-79 as moderate CVH, and 80-100 as high CVH. In the fully adjusted model, each one-point increase in the LE8 score corresponded to a 2.7, 2.7, and 1.6% decrease in all-cause, CVD, and cancer mortality risk, respectively, in people with MASLD. Compared to low CVH, being in moderate/high CVH was negatively associated with most mortality outcomes, while health factors lost significant association with cancer mortality.

The association between alcohol consumption and cardiometabolic factors and liver fibrosis in metabolic dysfunction-associated steatotic liver disease and metabolic dysfunction and alcohol-associated liver disease

BACKGROUND

The relationships between alcohol consumption, cardiometabolic factors, and liver fibrosis in patients with metabolic dysfunction-associated steatotic liver disease and those with metabolic dysfunction and alcohol-associated liver disease remain unclear.

AIMS

To investigate the longitudinal associations among alcohol consumption, cardiometabolic factors, and liver fibrosis in patients with these two liver diseases.

METHODS

This observational cohort study included 1866 patients with metabolic dysfunction-associated steatotic liver disease and 521 patients with metabolic dysfunction and alcohol-associated liver disease who underwent > two health checkups over >2 years. The associations of both liver diseases with worsening non-invasive liver fibrosis scores were assessed using the Cox regression analysis.

RESULTS

Both liver diseases independently worsened liver fibrosis in both sexes. However, the hazard ratio for worsening liver fibrosis in females was significantly higher with metabolic dysfunction and alcohol-associated liver disease than with metabolic dysfunction-associated steatotic liver disease. Worsening liver fibrosis was not associated with alcohol consumption. Among males with metabolic dysfunction-associated steatotic liver disease, the hazard ratio for worsening liver fibrosis was significantly higher in those with multiple cardiometabolic factors compared to those with a single cardiometabolic factor.

CONCLUSIONS

Although both metabolic steatotic liver disease and metabolic alcohol-associated liver disease were correlated with liver fibrosis progression in both sexes, the impact of alcohol consumption and cardiometabolic factors on fibrosis progression differed by sex. Cardiometabolic factors may have a stronger impact on liver fibrosis than alcohol consumption in males with metabolic dysfunction-associated steatotic liver disease.

Metabolic (dysfunction)-associated fatty liver disease metrics and contributions to liver research

BACKGROUND

The international consensus to revise non-alcoholic fatty liver disease to metabolic (dysfunction)-associated fatty liver disease (MAFLD) in 2020 attracted significant attention. The impact of the MAFLD definition on the research community has not been objectively assessed. We conducted an analysis of systematically collected literature on MAFLD to understand its research impact.

METHODS

From PubMed, Web of Science, and Scopus, the literature adopting MAFLD, written in English, and published from 2020 to 10 October 2023 was collected. The publication metrics, including publication counts, publishing journals, author countries, author keywords, and citation information, were analyzed to evaluate the research impact and key topics on MAFLD.

RESULTS

1469 MAFLD-related papers were published in 434 journals with a steady increase in the number. The intense publishing and citations activity on MAFLD indicates the large impact of the redefinition. Topic assessment with keyword and citation analysis revealed a transition from the proposal and discussion of the redefinition to clinical characterization of MAFLD with a focus on metabolic dysfunction. Moreover, the diagnostic criteria for MAFLD showed better performance in predicting hepatic and extrahepatic outcomes compared to NAFLD. The publications were from 99 countries with evidence of strong regional and global collaboration. Multiple international societies and stakeholders have endorsed MAFLD for its utility in clinical practice, improving patient management and promoting multidisciplinary care, while alleviating stigma.

CONCLUSION

This survey provides a quantitative measure of the considerable international impact and contributions of the MAFLD definition towards liver research and as part of the spectrum of cardiometabolic disorders.

Prevalence of steatotic liver disease, advanced fibrosis and cirrhosis among community-dwelling overweight and obese individuals in the USA

BACKGROUND

There are limited prospective data among overweight and obese individuals on the prevalence of advanced fibrosis, and cirrhosis using advanced MRI-based methods in the USA. The aim of this study was to fill that gap in knowledge by prospectively determining the MRI-based prevalence of steatotic liver disease (SLD) and its subcategories, advanced fibrosis and cirrhosis among overweight and obese individuals residing in the USA.

METHODS

This is a cross-sectional analysis of prospectively enrolled overweight or obese adults aged 40-75 years from primary care and community-based settings in Southern California. Participants were classified as having SLD if MRI proton density fat fraction ≥5%, and subclassified as metabolic dysfunction-associated steatotic liver disease (MASLD), metabolic dysfunction and alcohol-associated liver disease (MetALD) and alcohol-related liver disease (ALD) consistently with the new nomenclature guidance per AASLD-EASL-ALEH. Advanced fibrosis and cirrhosis were defined as magnetic resonance elastography (MRE) ≥3.63 kPa and MRE ≥4.67 kPa, respectively.

RESULTS

The cohort included 539 participants with mean (±SD) age of 51.5 (±13.1) years and body mass index of 32.6 (±6.2) kg/m2, respectively. The prevalence of SLD, advanced fibrosis and cirrhosis was 75%, 10.8% and 4.5%, respectively. The prevalence of MASLD, MetALD and ALD was 67.3%, 4.8% and 2.6%, respectively. There was no difference in prevalence of advanced fibrosis and cirrhosis among subcategories.

CONCLUSIONS

Using advanced MRI methods among community-dwelling overweight and obese adults, the prevalence of cirrhosis was 4.5%. Most common SLD subcategory was MASLD with 67% of individuals, whereas MetALD and ALD were less common. Systematic screening for advanced fibrosis among overweight/obese adults may be considered.

Metabolic characteristics of patients with MetALD: Caveats of a new definition

BACKGROUND AND AIMS

Recently, a new entity was introduced, MetALD, which includes patients with metabolic dysfunction-associated steatotic liver disease (MASLD), who consume moderate amounts of alcohol. However, little is known regarding the metabolic and clinical characteristics of these patients.

METHODS

Data from the National Health and Nutrition Examination Surveys 2017-2020 was used. Participants without valid transient elastography (TE) measurements, incomplete alcohol consumption report, or with alternative etiologies of liver steatosis were excluded.

RESULTS

A total of 6901 patients were included in the study, of which 106 (1.5%) had MetALD. Overall, MetALD patients showed a metabolic profile that was more similar to patients with alcohol related liver disease (ALD) than MASLD. Specifically, while patients with MetALD showed values in-between MASLD and ALD for body mass index (BMI), aspartate transaminase (AST), alanine transaminase (ALT), gamma glutamyltransferase (GGT) and haemoglobin A1c, they had similar high-density lipoprotein cholesterol (HDL-C), blood pressure, prevalence of diabetes and insulin resistance to ALD patients. Increasing alcohol consumption was associated with lower insulin resistance and A1c and higher triglycerides, HDL-C and blood pressure. Moreover, while AST, ALT and GGT increased with alcohol consumption, this did not translate into worse hepatic steatosis or liver fibrosis by TE.

CONCLUSIONS

MetALD patients share some characteristics with MASLD, but they resemble ALD patients more, especially after adjusting for BMI. Alcohol consumption produces a dissociation between insulin resistance and some cardiometabolic risk factors (blood pressure and HDL-C), which may make the current classification of patients challenging.

Metabolic Dysfunction-Associated Steatotic Liver Disease in Type 2 Diabetes Mellitus: A Review and Position Statement of the Fatty Liver Research Group of the Korean Diabetes Association

Since the role of the liver in metabolic dysfunction, including type 2 diabetes mellitus, was demonstrated, studies on non-alcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated fatty liver disease (MAFLD) have shown associations between fatty liver disease and other metabolic diseases. Unlike the exclusionary diagnostic criteria of NAFLD, MAFLD diagnosis is based on the presence of metabolic dysregulation in fatty liver disease. Renaming NAFLD as MAFLD also introduced simpler diagnostic criteria. In 2023, a new nomenclature, steatotic liver disease (SLD), was proposed. Similar to MAFLD, SLD diagnosis is based on the presence of hepatic steatosis with at least one cardiometabolic dysfunction. SLD is categorized into metabolic dysfunction-associated steatotic liver disease (MASLD), metabolic dysfunction and alcohol-related/-associated liver disease, alcoholrelated liver disease, specific etiology SLD, and cryptogenic SLD. The term MASLD has been adopted by a number of leading national and international societies due to its concise diagnostic criteria, exclusion of other concomitant liver diseases, and lack of stigmatizing terms. This article reviews the diagnostic criteria, clinical relevance, and differences among NAFLD, MAFLD, and MASLD from a diabetologist's perspective and provides a rationale for adopting SLD/MASLD in the Fatty Liver Research Group of the Korean Diabetes Association.

Clinical outcomes of MAFLD versus NAFLD: A meta-analysis of observational studies

IMPORTANCE

The recent change in terminology from nonalcoholic fatty liver disease (NAFLD) to metabolic dysfunction-associated fatty liver disease (MAFLD) and metabolic dysfunction-associated steatotic liver disease (MASLD) highlights the link between hepatic steatosis and metabolic dysfunction, taking out the stigmata of alcohol.

OBJECTIVE

We compared the effects of NAFLD and MAFLD definitions on the risk of overall and cardiovascular (CV) mortality, liver-related events (LRE), nonfatal CV events (CVE), chronic kidney disease (CKD), and extra-hepatic cancers (EHC).

DATA SOURCES AND STUDY SELECTION

We systematically searched four large electronic databases for cohort studies (published through August 2023) that simultaneously used NAFLD and MAFLD definitions for examining the risk of mortality and adverse CV, renal, or oncological outcomes associated with both definitions. In total, 21 eligible cohort studies were identified. Meta-analysis was performed using random-effects modelling.

RESULTS

Compared with those with NAFLD, individuals with MAFLD had significantly higher rates of overall mortality (random-effect OR 1.12, 95% CI 1.04-1.21, p = .004) and CV mortality (random-effect OR 1.15, 95% CI 1.04-1.26, p = .004), and a marginal trend towards higher rates of developing CKD (random-effect OR 1.06, 95% CI 1.00-1.12, p = .058) and EHC events (random-effect OR 1.11, 95% CI 1.00-1.23, p = .052). We found no significant differences in the risk LREs and nonfatal CVE between MAFLD and NAFLD. Meta-regression analyses identified male sex and metabolic comorbidities as the strongest risk factors related to the risk of adverse clinical outcomes in MAFLD compared to NAFLD.

CONCLUSIONS AND RELEVANCE

Individuals with MAFLD have higher rates of overall and CV mortality and higher rates of developing CKD and EHC events than those with NAFLD, possibly due to the dysmetabolic risk profile related to MAFLD.

Disparities in steatosis prevalence in the United States by Race or Ethnicity according to the 2023 criteria

INTRODUCTION

The 2023 nomenclature defined criteria for steatotic liver disease (SLD), including metabolic dysfunction-associated SLD (MASLD), alcohol-associated liver disease (ALD), and the overlapping MASLD/ALD (MetALD). We aimed to assess racial and ethnic disparities in the SLD prevalence among United States (US) adults based on this new nomenclature.

METHODS

We undertook a cross-sectional study employing the 2017-2018 National Health and Nutrition Examination Survey (NHANES) database. We identified SLD according to a controlled attenuation parameter ≥288 dB/m, liver stiffness ≥7.2 kPa, or elevated aminotransferase levels. Alcohol use thresholds were established according to the updated SLD definition. We estimated prevalences using the complex design of the NHANES survey. Multivariable logistic regressions with complex design weights were employed.

RESULTS

A total of 5532 individuals are included. The mean age is 45.4 years, and 50.9% are women. The adjusted estimated prevalence of MASLD is 42.4% (95% CI: 41.1-43.8%), MetALD 1.7% (95% CI: 1.3-2.0%), and ALD 0.6% (95% CI: 0.3-0.8%). Hispanics exhibit a higher prevalence of SLD, but there are no significant differences in advanced fibrosis prevalence due to SLD among racial/ethnic groups. In MASLD, men, individuals aged 40-64 and ≥65 years, Hispanics, those with health insurance, higher BMI, diabetes, hypertension, hypertriglyceridemia, and low high-density lipoprotein (HDL) cholesterol or use of lipid-lowering agents are independently associated with a higher risk, while Blacks have the lowest risk. In MetALD, men and higher BMI are independently associated with a higher risk of MetALD in adjusted multivariable analysis. In ALD, the adjusted multivariable analysis shows that only health insurance is independently associated with a lower ALD risk.

CONCLUSIONS

MASLD prevalence is high in the US, especially in men, older individuals, and Hispanics. MetALD and ALD prevalence was substantial but could be underestimated.

Assessment of the clinical value of five noninvasive predictors of metabolic dysfunction-associated steatotic liver disease in Han Chinese adults

BACKGROUND

Fatty Liver Index (FLI), Triglyceride-Glucose Index (TyG), Lipid Accumulation Product (LAP), Zhejiang University Index (ZJU), and Visceral Adiposity Index (VAI) are five classical predictive models for fatty liver disease. Our cross-sectional study aimed to identify the optimal predictors by comparing the predictive value of five models for metabolic dysfunction-associated steatotic liver disease (MASLD) risk.

METHODS

Data on 2687 participants were collected from West China Hospital of Sichuan University. Controlled attenuation parameters assessed by transient elastography were used to effectively diagnose MASLD. Logistic regression analysis was used to estimate the odd ratios and 95% confidence intervals between indices and MASLD risk. Receiver operating characteristic curves were plotted to evaluate the predictive value of indices.

RESULTS

This study included 1337 normal and 1350 MASLD samples. The average age of MASLD patients is 47 years old, and the prevalence was higher in males (39.3%) than in females (10.9%). Five indices were positively correlated with MASLD risk, with the strongest correlation for TyG. Overall, the area under the curve of the indicators was: ZJU 0.988, FLI 0.987, LAP 0.982, TyG 0.942, and VAI 0.941. In the gender stratification, ZJU (0.989) performed best in males. FLI (0.988) and ZJU (0.987) had similar predictive ability in females. In the age stratification, FLI performed better in predicting the middle-aged group aged 30-40 years (0.991).

CONCLUSION

For Chinese Han adults, ZJU is the best predictive index for initial screening of MASLD. FLI can serve as an alternative tool for ZJU to predict females.

Lights and shadows in the new definition of steatotic liver disease

The presence of marked hepatic steatosis in patients with high alcohol consumption was first described in 1836 by Addison et al.1 Many years later, in 1980, Ludwig and colleagues described a histological picture very similar to that seen in patients with alcoholic hepatitis but who did not consume alcohol, coining the term non-alcoholic steatohepatitis (NASH).2 In recent years, the terminology used to describe conditions related to hepatic steatosis has undergone significant evolution. In 2020, Eslam et al.3 subsequently modified it to MAFLD (Metabolic Associated Fatty Liver Disease) to better reflect its association with metabolic dysfunction, a nomenclature that, from the beginning, generated some reluctance due to the absence of clear international consensus.

Time Trends in Liver-Related Mortality in People With and Without Diabetes: Results From a Population-Based Study

CONTEXT

Patients with diabetes are at increased risk of dying from liver-related events, but little is known on whether this increased risk has changed in recent years.

OBJECTIVE

The aim of the present study is to describe time trends in cause-specific liver-related mortality in people with and without diabetes from the general Italian population.

METHODS

Data were retrieved from the health care utilization databases of Lombardy, a region of Italy that accounts for about 16% (almost 10 million) of its population. Annual cause-specific mortality rates and proportionate mortality were computed among individuals with and without diabetes from 2010 to 2019. Liver-related deaths were categorized as viral, alcohol related, and nonviral nonalcohol related (NVNA).

RESULTS

Liver diseases were responsible for 2% and 1% of deaths in people with and without diabetes (2019). Among patients with diabetes, the crude mortality rate for liver diseases decreased from 1.13 to 0.64 deaths per 1000 person-years from 2010 to 2019. The largest proportion of liver-related deaths was attributable to NVNA diseases and it increased from 63% in 2010 to 68% in 2019, with a corresponding relative reduction of viral causes (from 27% to 23%). The standardized mortality ratio for patients with diabetes was 3.35 (95% CI 2.96-3.76) for NVNA, 1.66 (95% CI 1.33-2.01) for viral hepatitis, and 1.61 (95% CI 1.13-2.17) for alcoholic liver disease and it remained relatively stable over time. Excess mortality risk in patients with diabetes for liver-related mortality was higher than for cardiovascular mortality and cancer.

CONCLUSION

While liver-related mortality rates decreased significantly among patients with diabetes, NVNA causes made up the majority of cases. Excess mortality for liver-related causes in patients with diabetes compared with controls remained constant in the studied period.

Impacts of cardiometabolic risk factors and alcohol consumption on all-cause mortality among MASLD and its subgroups

BACKGROUND AND AIMS

Recently, metabolic dysfunction-associated steatotic liver disease (MASLD) has been introduced. However, research on this new nomenclature and definition remains limited. This study aims to assess the impact of cardiometabolic risk factors and alcohol consumption on all-cause mortality in MASLD and its subgroups.

METHODS AND RESULTS

We included 2408 participants with MASLD in NHANES III and their linked mortality through 2019. MASLD patients were divided into two groups based on alcohol consumption: Pure MASLD and MetALD. The Cox proportional hazard model was used to assess the association between factors and all-cause mortality. During the median 26.0-year follow-up, there were 1040 deaths. The multivariable Cox regression analysis revealed a significant increase of over two-fold in the all-cause mortality rate among patients with four or more cardiometabolic risk factors compared to those with only one. When focusing on each component of cardiometabolic risk factors individually, only diabetes and hypertension were significantly associated with all-cause mortality (p < 0.05). In a subgroup analysis, each additional cardiometabolic factor was linked to an increase in all-cause mortality in both pure MASLD (hazard ratio 1.16; 95% CI 1.06-1.28; p = 0.002) and MetALD (HR 1.77; 95% CI 1.26-2.49; p = 0.001). Notably, an elevation in alcohol consumption was significantly associated with an increase in all-cause mortality rate only in the MetALD (p < 0.001).

CONCLUSIONS

This study found that the presence of diabetes or hypertension was significantly associated with all-cause mortality. We also explored the different impacts of these factors and alcohol consumption within MASLD subgroups.

Trajectories of hepatic steatosis and incidence of cardiovascular disease over a 29-year follow-up

AIM

To examine the dynamic change in hepatic steatosis status during repeated assessments over time, and its potential impact on the risk of developing cardiovascular disease (CVD).

METHODS

We assessed trajectories of hepatic steatosis and other metabolic disorders in 3134 middle-aged adults undergoing longitudinal assessment of ultrasonography during a pre-baseline period (1993-2009) in a population-based cohort study of liver health. Subsequently, we determined the association of hepatic steatosis trajectories with the incidence of CVD among 2185 CVD-free individuals, followed until 2021. Metabolic risk factors and cardiovascular events (including coronary heart disease and stroke) were determined through medical examination and linkage with nationwide health databases.

RESULTS

We identified three discrete trajectories of hepatic steatosis according to changing pattern over time through group-based trajectory modeling: "stable, non-steatosis" (n = 1298), "intermittent" (n = 921), and "persistent steatosis" (n = 915). During the pre-baseline period, hepatic steatosis trajectories were associated with trajectories of developing diabetes and hypertension, and persistent steatosis (vs. other trajectories) was associated with higher risks and rapidly progressive disease patterns. At a median 13.6 years of follow-up, 629 CVD events occurred. A persistent (vs. non-steatosis: HR 1.44, 95% CI 1.17-1.76), but not intermittent, steatosis pattern predicted the future risk of CVD, after adjustment for age, sex, smoking, and obesity. This association was independent of genetic background, and remained after accounting for pre-baseline body-mass index, other cardiometabolic risk factors, Framingham risk score, medications, and hepatic fibrosis score.

CONCLUSIONS

The persistence of hepatic steatosis is associated with trajectories of metabolic disorder development and increased risk of CVD. These data have important implications for practice and further research.

A narrative review of lifestyle management guidelines for metabolic dysfunction-associated steatotic liver disease

BACKGROUND AND AIMS

Metabolic dysfunction-associated steatotic liver disease management guidelines have been published worldwide; we aimed to summarize, categorize, and compare their lifestyle intervention recommendations.

APPROACH AND RESULTS

We searched metabolic dysfunction-associated steatotic liver disease/NAFLD management guidelines published between January 1, 2013, and June 31, 2024, through databases including PubMed/MEDLINE, Cochrane, and CINAHL. In total, 35 qualifying guidelines were included in the final analysis. Guideline recommendations were categorized into 5 domains (ie, weight reduction goals, physical activity, nutrition, alcohol, and tobacco smoking) and were ranked based on how frequently they appeared. A recommendation was defined as widely adopted if recommended in ≥24 (≥66.6%) of the guidelines. These included increasing physical activity; reducing body weight by 7%-10% to improve steatohepatitis and/or fibrosis; restricting caloric intake; undertaking 150-300 or 75-150 minutes/week of moderate or vigorous-intensity physical activity, respectively; and decreasing consumption of commercially produced fructose. The least mentioned topics, in ≤9 of the guidelines, evaluated environmental determinants of health, mental health, referring patients for psychological or cognitive behavioral therapy, using digital health interventions, and assessing patients' social determinants of health.

CONCLUSIONS

Most guidelines recommend weight reduction through physical activity and improving nutrition, as these have proven positive effects on health outcomes when sustained. However, gaps regarding mental health and the social and environmental determinants of metabolic dysfunction-associated steatotic liver disease were found. To optimize behavioral modifications and treatment, we recommend carrying out studies that will provide further evidence on social support, environmental factors, and mental health, as well as further exploring digital health interventions.

Glucagon-like peptide 1 agonists are potentially useful drugs for treating metabolic dysfunction-associated steatotic liver disease

In this editorial, we comment on Yin et al's recently published Letter to the editor. In particular, we focus on the potential use of glucagon-like peptide 1 receptor agonists (GLP-1RAs) alone, but even more so in combination therapy, as one of the most promising therapies in metabolic dysfunction-associated steatotic liver disease (MASLD), the new definition of an old condition, non-alcoholic fatty liver disease, which aims to better define the spectrum of steatotic pathology. It is well known that GLP-1RAs, having shown outstanding performance in fat loss, weight loss, and improvement of insulin resistance, could play a role in protecting the liver from progressive damage. Several clinical trials have shown that, among GLP-1RAs, semaglutide is a safe, well-studied therapeutic choice for MASLD patients; however, most studies demonstrate that, while semaglutide can reduce steatosis, including steatohepatitis histological signs (in terms of inflammatory cell infiltration and hepatocyte ballooning), it does not improve fibrosis. Combinations of therapies with different but complementary mechanisms of action are considered the best way to improve efficiency and slow disease progression due to the complex pathophysiology of the disease. In particular, GLP-1RAs associated with antifibrotic drug therapy, dual glucose-dependent insulinotropic polypeptide (GIP)/GLP-1RA or GLP-1 and glucagon RAs have promoted greater improvement in hepatic steatosis, liver biochemistry, and non-invasive fibrosis tests than monotherapy. Therefore, although to date there are no definitive indications from international drug agencies, there is the hope that soon the therapeutic lines in the most advanced phase of study will be able to provide a therapy for MASLD, one that will certainly include the use of GLP-1RAs as combination therapy.

Mechanisms of Non-alcoholic Fatty Liver Disease and Beneficial Effects of Semaglutide: A Review

Non-alcoholic fatty liver disease stands as the predominant cause of chronic liver disease, with its prevalence and morbidity expected to escalate significantly, leading to substantial healthcare costs and diminished health-related quality of life. It comprises a range of disease manifestations that commence with basic steatosis, involving the accumulation of lipids in hepatocytes, a distinctive histological feature. If left untreated, it often advances to non-alcoholic steatohepatitis, marked by inflammatory and/or fibrotic hepatic changes, leading to the eventual development of non-alcoholic fatty liver disease-related cirrhosis and hepatocellular carcinoma. Because of the liver's vital role in body metabolism, non-alcoholic fatty liver disease is considered both a consequence and a contributor to the metabolic abnormalities observed in the metabolic syndrome. As of date, there are no authorized pharmacological agents for non-alcoholic fatty liver disease or non-alcoholic steatohepatitis. Semaglutide, with its glycemic and weight loss advantages, could potentially offer benefits for individuals with non-alcoholic fatty liver disease. This review aims to investigate the impact of semaglutide on non-alcoholic fatty liver disease.

Current status and future trends of the global burden of MASLD

Metabolic dysfunction-associated steatotic liver disease (MASLD) has emerged as the most common chronic liver disease globally, affecting more than a third of the world's adult population. This comprehensive narrative review summarizes the global incidence and prevalence rates of MASLD and its related adverse hepatic and extrahepatic outcomes. We also discuss the substantial economic burden of MASLD on healthcare systems, thus further highlighting the urgent need for global efforts to tackle this common and burdensome liver condition. We emphasize the clinical relevance of early interventions and a holistic approach that includes public health strategies to reduce the global impact of MASLD.

Impact of MASLD and MetALD on clinical outcomes: A meta-analysis of preliminary evidence

A recent Delphi consensus proposed a new definition for metabolic dysfunction associated steatotic liver disease (MASLD) and introduced a disease entity called MetALD, a condition in which steatotic liver disease (SLD), metabolic dysfunction and moderate alcohol intake coexist. Given the limited available data on the prognostic implications of these disease entities, we performed a systematic review and meta-analysis of available cohort studies to evaluate the association of MASLD and MetALD with hard clinical outcomes. We included 5 studies for a total of 9 824 047 participants. Compared with participants without SLD, increased rates of all-cause mortality and incident cardiovascular disease were present for both MASLD and MetALD. Moreover, MetALD was also associated with significantly higher risks of cancer-related mortality (n = 2 studies, random-effects HR 2.10, 95% CI 1.35-3.28) and cardiovascular mortality (n = 3 studies, random-effects HR 1.17, 95% CI 1.12-1.22). Although preliminary, available evidence indicates a more unfavourable prognosis for patients with MetALD compared with those with MASLD.

Comparing similarities and differences between NAFLD, MAFLD, and MASLD in the general U.S. population

Background

Recently, the multisociety Delphi consensus renamed non-alcoholic fatty liver disease (NAFLD) terminology [previously renamed metabolic-associated fatty liver disease (MAFLD)] as metabolic dysfunction-associated steatotic liver disease (MASLD). The aim of this study was to compare the similarities and differences between NAFLD, MAFLD, and MASLD and to clarify the impact of this new name change.

Methods

A cross-sectional study of 3,035 general subjects with valid vibration-controlled transient elastography data was conducted based on data from the National Health and Nutrition Examination Survey (NHANES) 2017-2020. NAFLD, MAFLD, and MASLD were defined according to the corresponding consensus criteria.

Results

Using controlled attenuation parameter (CAP) ≥274 dB/m and liver stiffness measurements (LSM) ≥9.7 kPa as the cutoff values for the presence of hepatic steatosis and advanced liver fibrosis (ALF), the prevalence of NAFLD, MAFLD, and MASLD were 38.01% (95% CI 35.78-40.29%), 41.09% (39.09-43.12%), and 37.9% (35.70-40.14%), respectively, and the corresponding prevalence of ALF was 10.21% (7.09-14.48%), 10.13% (7.06-14.35%), and 10.24% (7.11-14.53%), respectively. The kappa values for the three definitions were above 0.9. The prevalence and severity of the three definitions remained similar when the sensitivity analyses were performed using different CAP thresholds. The prevalence of NAFLD, MAFLD, MASLD, and ALF increased as the number of cardiometabolic risk factors (CMRF) increased.

Conclusions

Our findings highlight the consistency among the three definitions, especially between NAFLD and MASLD, so that the new consensus will not disturb the original NAFLD-related findings. Additionally, more attention should be paid to patients with a high number of CMRFs.

Influence of MAFLD and NAFLD on arterial stiffness: A longitudinal cohort study

BACKGROUND AND AIMS

This cohort study investigated associations of nonalcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated fatty liver disease (MAFLD) with risk of increase in arterial stiffness (AS), measured as brachial-ankle pulse wave velocity (baPWV).

METHODS AND RESULTS

Participants who had health examinations between 2006 and 2019 were analyzed for fatty liver and increased baPWV using liver ultrasonography and automatic volume plethysmography device. Participants were classified based on presence of MAFLD or NAFLD and further divided into subgroups: no fatty liver disease (reference), NAFLD-only, MAFLD-only, and both NAFLD and MAFLD. Subgroups were additionally stratified by sex. Cox proportional hazard model was utilized to analyze the risk of developing baPWV ≥1400 cm/s in participants without baseline elevation of the baPWV. The NAFLD and MAFLD groups exhibited higher risks of increased baPWV (NAFLD: adjusted hazard ratio (aHR), 1.35 [95% CI, 1.29-1.42]; MAFLD: aHR, 1.37 [95% CI, 1.31-1.43]) compared to group without the conditions. Incidence of NAFLD or MAFLD were higher in men than in women but aHR of developing the increase in AS was higher in women. In subgroup analysis, the MAFLD-only group presented the strongest associations with increase in AS (aHR, 1.53 [95% CI, 1.43-1.64]), with the trend more pronounced in women than in men (Women, aHR, 1.63 [95% CI, 1.08-2.46]; Men, aHR 1.45 [95% CI, 1.35-1.56]).

CONCLUSIONS

Both NAFLD and MAFLD are significantly associated with elevated AS. These associations tended to be stronger in MAFLD than in NAFLD, in women than in men.

The relevance of intestinal barrier dysfunction, antimicrobial proteins and bacterial endotoxin in metabolic dysfunction-associated steatotic liver disease

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a leading cause of end-stage liver disease associated with increased mortality and cardiovascular disease. Obesity and diabetes are the most important risk factors of MASLD. It is well-established that obesity-associated insulin resistance leads to a situation of tissue lipotoxicity characterized by an accumulation of excess fat in non-fat tissues such as the liver, promoting the development of MASLD, and its progression into metabolic dysfunction-associated steatohepatitis.

METHODS

Here, we aimed to review the impact of disrupted intestinal permeability, antimicrobial proteins and bacterial endotoxin in the development and progression of MASLD.

RESULTS AND CONCLUSION

Recent studies demonstrated that obesity- and obesogenic diets-associated alterations of intestinal microbiota along with the disruption of intestinal barrier integrity, the alteration in antimicrobial proteins and, in consequence, an enhanced translocation of bacterial endotoxin into bloodstream might contribute to this pathological process through to impacting liver metabolism and inflammation.

Genetic correlations between liver fat content, metabolic health, and adiposity distribution in the Fels Longitudinal Study

BACKGROUND AND AIMS

Hepatic steatosis is known to be heritable, but its genetic basis is mostly uncharacterized. Steatosis is associated with metabolic and adiposity features; recent studies hypothesize that shared genetic effects between these traits could account for some of the unexplained heritability. This study aimed to quantify these genetic associations in a family-based sample of non-Hispanic white adults.

METHODS AND RESULTS

704 participants (18-95 years, 55.8% female) from the Fels Longitudinal Study with an MRI assessment of liver fat were included. Quantitative genetic analyses estimated the age- and sex-adjusted heritability of individual traits and the genetic correlations within trait pairs. Mean liver fat was 5.95% (SE = 0.23) and steatosis (liver fat >5.56%) was present in 29.8% of participants. Heritability (h2± SE) of steatosis was 0.72 ± 0.17 (p = 6.80e-6). All other traits including liver enzymes, fasting glucose, HOMA-IR, visceral and subcutaneous adipose tissue (VAT, SAT), body mass index, body fat percent, waist circumference, lipids and blood pressure were also heritable. Significant genetic correlations were found between liver fat and all traits except aspartate aminotransferase (AST), and among most trait pairs. Highest genetic correlations were between liver fat and HOMA-IR (0.85 ± 0.08, p = 1.73e-8), fasting glucose and ALT (0.89 ± 0.26, p = 6.68e-5), and HOMA-IR with: waist circumference (0.81 ± 0.12, p = 3.76e-6), body fat percent (0.78 ± 0.12 p = 2.42e-5) and VAT (0.73 ± 0.07, p = 6.37e-8).

CONCLUSIONS

Common genes may exist between liver fat accumulation, metabolic features and adiposity phenotypes.