Nonalcoholic fatty liver disease versus metabolic-associated fatty liver disease: Prevalence, outcomes and implications of a change in name

Global research trends on gut microbiota and metabolic dysfunction-associated steatohepatitis: Insights from bibliometric and scientometric analysis

Background

Metabolic dysfunction-associated steatohepatitis (MASH) is an inflammatory subtype of metabolic dysfunction-associated steatotic liver disease (MASLD) has recently been proposed as a replacement term for NAFLD, a common, multifactorial and poorly understood liver disease whose incidence is increasing worldwide. In recent years, there has been increasing scientific interest in exploring the relationship between gut microbiota and MASH. To learn more about the gut microbiota in MASH, this study aims to provide a comprehensive analysis of the knowledge structure and research hotspots from a bibliometric perspective.

Methods

We searched the Web of Science Core Collection for articles and reviews that covered the connections between gut microbiota and MASH over the last decade. The Online Analysis Platforms, VOSviewer, CiteSpace, the R tool "bibliometrix" were used to analyzed existing publications trends and hotspots.

Results

A total of 4,069 documents related to the interaction between gut microbiota and MASH were retrieved from 2014 to 2023. The number of annual publications increased significantly over the last decade, particularly in the United States and China. The University of California-San Diego was the most productive institution, while researcher Rohit Loomba published the most papers in the field. Younossi ZM was ranked as the first co-cited author and largest contributor of highly cited articles in the field. Gastroenterology and hepatology were the most common specialty category. The most cited journal in the last decade was Hepatology. The Keyword Bursts analysis highlighted the importance of studying the association between gut microbiota and MASH, as well as related factors such as metabolic syndrome, insulin resistance, endotoxemia and overgrowth of gut bacteria. Keyword clusters with co-citation were used to illustrate important topics including intestinal permeability, insulin sensitivity and liver immunology. The most common keywords include insulin resistance, obesity, dysbiosis, inflammation and oxidative stress, which are current hotspots.

Conclusion

Our analysis highlights key aspects of this field and emphasizes multiorgan crosstalk in MASLD/MASH pathogenesis. In particular, the central role of the gut-liver axis and the significant influence of gut microbiota dysbiosis on disease progression are highlighted. Furthermore, our results highlight the transformative potential of microbiota-specific therapies and cover the way for innovative healthcare and pharmaceutical strategies.

Changes in the terminology and diagnostic criteria of non-alcoholic fatty liver disease: Implications and opportunities

Fatty liver disease (FLD) is a highly prevalent pathological liver disorder. It has many and varied etiologies and has heterogeneous clinical course and outcome. Its proper nomenclature and classification have been problematic since its initial recognition. Traditionally, it was divided into two main categories: Alcohol-associated liver disease and nonalcoholic FLD (NAFLD). Among these, the latter condition has been plagued with nomenclature and classification issues. The two main objections to its use have been the use of negative (non-alcoholic) and stigmatizing (fatty) terms in its nomenclature. Numerous attempts were made to address these issues but none achieved universal acceptance. Just recently, NAFLD has received a new nomenclature from an international collaborative effort based on a rigorous scientific methodology. FLD has been renamed steatotic liver disease (SLD), and NAFLD as metabolic dysfunction-associated SLD. Metabolic dysfunction-associated steatohepatitis was chosen as the replacement terminology for non-alcoholic steatohepatitis. This is a significant positive change in the nomenclature and categorization of FLD and will likely have a major impact on research, diagnosis, treatment, and prognosis of the disease in the future.

Alteration of Gut Microbiota Composition in the Progression of Liver Damage in Patients with Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a complex disorder whose prevalence is rapidly growing in South America. The disturbances in the microbiota-gut-liver axis impact the liver damaging processes toward fibrosis. Gut microbiota status is shaped by dietary and lifestyle factors, depending on geographic location. We aimed to identify microbial signatures in a group of Chilean MASLD patients. Forty subjects were recruited, including healthy controls (HCs), overweight/obese subjects (Ow/Ob), patients with MASLD without fibrosis (MASLD/F-), and MASLD with fibrosis (MASLD/F+). Both MASLD and fibrosis were detected through elastography and/or biopsy, and fecal microbiota were analyzed through deep sequencing. Despite no differences in α- and β-diversity among all groups, a higher abundance of Bilophila and a lower presence of Defluviitaleaceae, Lachnospiraceae ND3007, and Coprobacter was found in MASLD/F- and MASLD/F+, compared to HC. Ruminococcaceae UCG-013 and Sellimonas were more abundant in MASLD/F+ than in Ow/Ob; both significantly differed between MASLD/F- and MASLD/F+, compared to HC. Significant positive correlations were observed between liver stiffness and Bifidobacterium, Prevotella, Sarcina, and Acidaminococcus abundance. Our results show that MASLD is associated with changes in bacterial taxa that are known to be involved in bile acid metabolism and SCFA production, with some of them being more specifically linked to fibrosis.

Differences in the prevalence of NAFLD, MAFLD, and MASLD according to changes in the nomenclature in a health check-up using MRI-derived proton density fat fraction

PURPOSE

International expert panels proposed new nomenclatures, metabolic dysfunction-associated fatty liver disease (MAFLD) in 2020 and metabolic dysfunction-associated steatotic liver disease (MASLD) in 2023, along with revised diagnostic criteria to replace non-alcoholic fatty liver disease (NAFLD). We aimed to investigate the differences in NAFLD, MAFLD, and MASLD prevalence with changing nomenclature in a health check-up using magnetic resonance imaging-derived proton density fat fraction (MRI-PDFF) to assess hepatic steatosis. We also examined the prevalence of the sub-classifications of steatotic liver disease (SLD) and the differences in characteristics among the sub-categories.

METHODS

We included 844 participants who underwent liver MRI-PDFF at our health check-up clinic between January 2020 and November 2022. Hepatic steatosis was defined as MRI-PDFF ≥ 5%. Participants were categorized according to NAFLD, MAFLD, MASLD, and sub-classifications of SLD.

RESULTS

The prevalence rates of NAFLD, MAFLD, and MASLD were 25.9%, 29.5%, and 25.2%, respectively. 30.5% of the participants was categorized as SLD. The prevalence rates of the SLD sub-categories were 25.2% for MASLD, 3.7% for MASLD and alcohol-associated liver disease (MetALD), 0.1% for alcohol-associated liver disease, 1.3% for specific etiology SLD, and 0.1% for cryptogenic SLD. Compared with patients in the MASLD group, those in the MetALD group were younger, predominantly male, and exhibited higher levels of serum aspartate aminotransferase, gamma-glutamyl transpeptidase, and triglycerides.

CONCLUSION

The prevalences of NAFLD and MASLD assessed using MRI-PDFF were similar, with MASLD accounting for 97.3% of the patients with NAFLD. The separate MetALD sub-category may have clinical characteristics that differ from those of MASLD.

Serum remnant cholesterol is a potential predictor of liver stiffness in patients with nonalcoholic fatty liver disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is associated with dyslipidemia, and the connection between dyslipidemia and remnant cholesterol (RC), a component of triglyceride-rich lipoproteins, remains enigmatic.

METHODS

In this cross-sectional study, our primary aim was to investigate the role of RC in the progression of NAFLD and to provide robust evidence of RC's involvement in the pathogenesis of NAFLD. We enrolled 2800 NAFLD patients from the National Health and Nutrition Examination Survey (NHANES). Logistic regression was employed to examine the relationship between serum RC levels and liver stiffness, while receiver operating characteristic (ROC) curve analysis was used to assess the diagnostic capability of RC.

RESULTS

RC exhibited an independent correlation with the extent of liver stiffness, with odds ratios (OR) of 1.02 for liver steatosis (p = 0.014) and 1.02 for liver fibrosis (p = 0.014). To predict NAFLD, the optimal RC thresholds were 17.25 mg/dL for males and 15.25 mg/dL for females in the case of liver steatosis. For advanced liver fibrosis, the best thresholds were 17.25 mg/dL for males and 16.25 mg/dL for females.

CONCLUSIONS

RC demonstrated a positive correlation with the degree of liver stiffness and exhibited superior diagnostic efficacy for liver steatosis and fibrosis compared to other cholesterol indicators.

Proposal of a Novel Serological Algorithm Combining FIB-4 and Serum M2BPGi for Advanced Fibrosis in Nonalcoholic Fatty Liver Disease

Background/Aims

Noninvasive methods have become increasingly critical in the diagnosis of fibrosis in chronic liver diseases. Herein, we compared the diagnostic performance of serum Mac2 binding protein glycosylation isomer (M2BPGi) and other serological panels for fibrosis in patients with nonalcoholic fatty liver disease (NAFLD) and proposed an improved two-step diagnostic algorithm for advanced fibrosis.

Methods

We enrolled 231 patients diagnosed with NAFLD who underwent a liver biopsy. We subsequently evaluated the diagnostic performance of serological panels, including serum M2BPGi, a fibrosis index based on four factors (FIB-4), aspartate aminotransferase-to-platelet ratio index (APRI), and NAFLD fibrosis score (NFS), in predicting the stage of liver fibrosis. We then constructed a two-step algorithm to better differentiate advanced fibrosis.

Results

The areas under the receiver operating characteristic curves of serum M2BPGi, FIB-4, APRI, and NFS for advanced fibrosis (≥F3) were 0.823, 0.858, 0.779, and 0.827, respectively. To reduce the performance of unnecessary liver biopsy, we propose a two-step algorithm using FIB-4 as an initial diagnostic tool and serum M2BPGi (≥0.6) as an additional diagnostic method for patients classified as intermediate (23%). Using the proposed algorithm, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 0.812, 0.814, 0.814, 0.600, and 0.927, respectively.

Conclusions

Serum M2BPGi is a simple and effective test for advanced fibrosis in patients with NAFLD. Application of the two-step algorithm based on FIB-4 and M2BPGi proposed here can improve diagnostic performance and reduce unnecessary tests, making diagnosis easily accessible, especially in primary medical centers.

Gentiopicroside improves non-alcoholic steatohepatitis by activating PPARα and suppressing HIF1

Gentiopicroside (GPS) is a highly water-soluble small-molecule drug and the main bioactive secoiridoid glycoside of Gentiana scabra that has been shown to have hepatoprotective effects against non-alcoholic steatohepatitis (NASH), a form of non-alcoholic fatty liver disease (NAFLD) that can progress to cirrhosis and hepatocellular carcinoma. However, the effects of GPS on NASH and the underlying mechanisms remain obscure. Firstly, a high-fat, high-cholesterol (HFHC) diet and a high-sugar solution containing d-fructose and d-glucose were used to establish a non-alcoholic steatohepatitis (NASH) mice model. Secondly, we confirmed GPS supplementation improve metabolic abnormalities and reduce inflammation in NASH mice induced by HFHC and high-sugar solution. Then we used metabolomics to investigate the mechanisms of GPS in NASH mice. Metabolomics analysis showed GPS may work through the Peroxisome Proliferator-Activated Receptor (PPAR) signaling pathway and glycine, serine, and threonine metabolism. Functional metabolites restored by GPS included serine, glycine, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). Western blot and qRT-PCR analysis confirmed GPS improve NASH by regulating PPARα and Hypoxia-Inducible Factor-1α (HIF-1α) signaling pathways. In vitro, studies further demonstrated EPA and DHA enhance fatty acid oxidation through the PPARα pathway, while serine and glycine inhibit oxidative stress through the HIF-1α pathway in palmitic acid-stimulated HepG2 cells. Our results suggest GPS's anti-inflammatory and anti-steatosis effects in NASH progression are related to the suppression of HIF-1α through the restoration of L-serine and glycine and the activation of PPARα through increased EPA and DHA.

Mortality in metabolic dysfunction-associated steatotic liver disease: A nationwide population-based cohort study

BACKGROUND

A new fatty liver disease nomenclature, steatotic liver disease (SLD) has been proposed; however, there are no data on clinical outcomes. We investigated the impact of SLD with metabolic dysfunction (MD; SLD-MD) on all-cause mortality.

METHODS

We evaluated nationally representative participants aged ≥19 years using data from the Korea National Health and Nutrition Examination Survey 2007-2015 and their linked death data through 2019. The presence of fatty liver disease was assessed by liver fat score, fatty liver index and significant liver fibrosis was evaluated by the Fibrosis-4 Index, and fibrosis score. SLD-MD was categorized into three groups: metabolic dysfunction-associated steatotic liver disease (MASLD); metabolic alcoholic liver disease (MetALD); and SLD with other combination etiologies.

RESULTS

Among 26734 individuals (11561 men and 15173 women, mean age 48.8 years), 1833 (6.9 %) died during a mean follow-up period of 110.6 ± 33.9 months. Mortality risk was significantly higher in individuals with SLD-MD (hazard ratio [HR] = 1.35) than in those without (P < 0.001). Among the three groups, MASLD (HR = 1.32) and SLD with other combination etiologies (HR = 2.06) independently increased mortality risk (all P < 0.001). When individuals with SLD-MD had significant liver fibrosis or diabetes, mortality risk increased further (HR = 1.68 and 1.85, respectively; all P < 0.001). SLD-MD with both significant liver fibrosis and diabetes showed the highest mortality risk (HR = 2.29, P < 0.001). When applied fatty liver index and fibrosis score, similar results were observed.

CONCLUSIONS

SLD-MD is associated with a higher mortality risk. When SLD-MD was combined with significant liver fibrosis or diabetes, the mortality risk became much higher. Treatment strategies to reduce fibrotic burden and improve glycemic control in individuals with MASLD are needed.

Association of composite dietary antioxidant index and muscle mass in individuals with metabolic associated fatty liver disease

BACKGROUND

There is mounting evidence indicating the association between oxidative stress and the detrimental effect it poses on muscle mass. However, the crucial interplay between the Composite Dietary Antioxidant Index (CDAI), a key metric of antioxidant-rich diets, and the occurrence of muscle loss has remained largely unexplored. Hence, in this study, we aim to investigate the potential relationship between CDAI and muscle loss METHODS: This cross-sectional investigation harnessed data sourced from the National Health and Nutrition Examination Survey (2017 and 2018) to meticulously scrutinize the correlation between the CDAI and the occurrence of muscle loss. To unravel this intricate relationship, we engaged in multivariate weighted logistic regression analysis and employed smooth curve fitting techniques. Additionally, subgroup analyses were meticulously performed.

RESULTS

A total of 956 participants, with an average age of 42.15 years, were included in the final analysis, of which 52.19 % were males. Notably, the prevalence of low muscle mass among the study population was observed to be 15.48 %. The utilization of smooth curve fitting analysis underscored a nearly linear association between the CDAI and the presence of low muscle mass. Employing multivariate weighted logistic regression analysis, it was determined that the odds ratio (OR) between CDAI and low muscle mass was 0.88 (95 % [CI], 0.73-0.95). Through subgroup analyses, we further validated that CDAI independently mitigated the risk of muscle loss.

CONCLUSION

Higher CDAI levels were found to be associated with an reduced risk of low muscle mass in adults with metabolic associated fatty liver disease (MAFLD).

A Genome-Wide Association Study of Metabolic Syndrome in the Taiwanese Population

The purpose of this study was to investigate genetic factors associated with metabolic syndrome (MetS) by conducting a large-scale genome-wide association study (GWAS) in Taiwan, addressing the limited data on Asian populations compared to Western populations. Using data from the Taiwan Biobank, comprehensive clinical and genetic information from 107,230 Taiwanese individuals was analyzed. Genotyping data from the TWB1.0 and TWB2.0 chips, including over 650,000 single nucleotide polymorphisms (SNPs), were utilized. Genotype imputation using the 1000 Genomes Project was performed, resulting in more than 9 million SNPs. MetS was defined based on a modified version of the Adult Treatment Panel III criteria. Among all participants (mean age: 50 years), 23% met the MetS definition. GWAS analysis identified 549 SNPs significantly associated with MetS, collectively mapping to 10 genomic risk loci. Notable risk loci included rs1004558, rs3812316, rs326, rs4486200, rs2954038, rs10830963, rs662799, rs62033400, rs183130, and rs34342646. Gene-set analysis revealed 22 associated genes: CETP, LPL, APOA5, SIK3, ZPR1, APOC1, BUD13, MLXIPL, TOMM40, GCK, YKT6, RPS6KB1, FTO, VMP1, TUBD1, BCL7B, C19orf80 (ANGPTL8), SIDT2, SENP7, PAFAH1B2, DOCK6, and FOXA2. This study identified genomic risk loci for MetS in a large Taiwanese population through a comprehensive GWAS approach. These associations provide novel insights into the genetic basis of MetS and hold promise for the potential discovery of clinical biomarkers.

Hepatocellular carcinoma surveillance - utilization, barriers and the impact of changing aetiology

Hepatocellular carcinoma (HCC) is the third leading cause of cancer death worldwide. Surveillance for HCC is critical for early detection and treatment, but fewer than one-quarter of individuals at risk of HCC undergo surveillance. Multiple failures across the screening process contribute to the underutilization of surveillance, including limited disease awareness among patients and health-care providers, knowledge gaps, and difficulty recognizing patients who are at risk. Non-alcoholic fatty liver disease and alcohol-associated liver disease are the fastest-rising causes of HCC-related death worldwide and are associated with unique barriers to surveillance. In particular, more than one-third of patients with HCC related to non-alcoholic fatty liver disease do not have cirrhosis and therefore lack a routine indication for HCC surveillance on the basis of current practice guidelines. Semi-annual abdominal ultrasound with measurement of α-fetoprotein levels is recommended for HCC surveillance, but the sensitivity of this approach for early HCC is limited, especially for patients with cirrhosis or obesity. In this Review, we discuss the current status of HCC surveillance and the remaining challenges, including the changing aetiology of liver disease. We also discuss strategies to improve the utilization and quality of surveillance for HCC.

Markers of insulin resistance associated with non-alcoholic fatty liver disease in non-diabetic population

Insulin resistance (IR) plays an important role in the development of non-alcoholic fatty liver disease (NAFLD). IR markers are divided into two types: (1) insulin-based IR marker, homeostatic model assessment of IR (HOMA-IR); and (2) non-insulin-based IR markers, such as triglyceride-glucose (TyG) index, TyG index with body mass index (TyG-BMI), triglyceride/high-density lipoprotein cholesterol ratio (TG/HDL-c), and metabolic score for IR (METS-IR). The non-insulin-based IR markers are often associated with lipids. The aim of this study was to analyse the association between IR markers and NAFLD in non-diabetic population. Baseline data of NAFLD and non-NAFLD groups were compared. Logistic regression was used to evaluate the relationship between five IR markers and NAFLD risk. The odds ratios (ORs) and 95% confidence intervals (CIs) of IR markers were calculated. Receiver operating characteristic (ROC) curves and area under the curve (AUC) were used to evaluate the ability of different IR markers to detect NAFLD. Subgroup analyses were performed in obese and non-obese subgroups. This study found a positive correlation between NAFLD risk and elevation in five IR markers (HOMA-IR, TyG, TyG-BMI, TG/HDL-c, and METS-IR). In non-obese subjects, the AUC of TyG-BMI was larger than that of the other four IR markers to detect NAFLD. The AUC of HOMA-IR was larger than that of the other four IR markers to detect NAFLD in obese subjects. In non-diabetic population, the five IR markers are associated with the risk of NAFLD, including non-obese and obese NAFLD. TyG-BMI and HOMA-IR can be used to detect non-obese and obese NAFLD, respectively, with better detection ability compared with the other IR markers.

Saponins of Tomato Extract Improve Non-Alcoholic Fatty Liver Disease by Regulating Oxidative Stress and Lipid Homeostasis

The present study investigated the impact of saponins of tomato extract (STE) on non-alcoholic fatty liver disease (NAFLD). The findings demonstrated that introducing STE in NAFLD mice revealed promising results in ameliorating symptoms of oxidative stress, lipid metabolism disorders, visceral fat deposition and fatty liver disease. Moreover, the mechanistic studies have demonstrated that STE delivers its effects by activating adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK), thereby suppressing downstream protein expression associated with fatty acid synthesis. In such conditions, lipid metabolism can be improved. Simultaneously, STE enhanced nuclear factor erythroid 2-related factor 2 (Nrf2) and entry into the nucleus and initiated the transcription of downstream antioxidant factors, thereby relieving oxidative stress induced by a high-fat diet and lowering oxidative damage to the liver. Such results imply that the administration of STE can be regarded as a viable treatment option for NAFLD, providing a mechanism that can regulate the AMPK and Nrf2 signaling pathways.

Sex-specific prevalence and risk factors of metabolic-associated fatty liver disease among 75,570 individuals in eastern China

Background

Metabolic-associated fatty liver disease (MAFLD) is a newly proposed definition and there is limited data on MAFLD prevalence. We aimed to investigate the prevalence of MAFLD in an eastern Chinese population.

Methods

This cross-sectional study included participants from an eastern Chinese population who underwent regular health checkups. Based on current diagnostic criteria, MAFLD was diagnosed in individuals with both hepatic steatosis and metabolic disorders. The overall and stratified prevalence derived based on sex, age, body mass index (BMI), and various metabolic disorders were estimated. Multivariate logistic regression analysis was used to determine the risk factors for MAFLD.

Results

Among the 75,570 participants, the overall prevalence of MAFLD was 37.32%, with higher rates in men (45.66%) than in women (23.91%). MAFLD prevalence was highest in men aged 40-49 years (52.21%) and women aged 70-79 years (44.77%). In all the BMI subgroups, the prevalence was higher in men than in women. In both sexes, the prevalence of MAFLD increased as BMI levels increased. Furthermore, MAFLD was associated with metabolic disorders, especially in the female participants with severe obesity (odds ratio 58.318; 95% confidence interval: 46.978-72.397).

Conclusion

MAFLD is prevalent in the general adult population in eastern China. Sex-specific differences in MAFLD prevalence were identified based on age, BMI, and metabolic disorders. MAFLD is associated with metabolic disorders, particularly obesity.

New Insights into the Pathogenesis of Metabolic-Associated Fatty Liver Disease (MAFLD): Gut-Liver-Heart Crosstalk

Metabolism-associated fatty liver disease (MAFLD) is a multifaceted disease that involves complex interactions between various organs, including the gut and heart. It is defined by hepatic lipid accumulation and is related to metabolic dysfunction, obesity, and diabetes. Understanding the intricate interplay of the gut-liver-heart crosstalk is crucial for unraveling the complexities of MAFLD and developing effective treatment and prevention strategies. The gut-liver crosstalk participates in the regulation of the metabolic and inflammatory processes through host-microbiome interactions. Gut microbiota have been associated with the development and progression of MAFLD, and its dysbiosis contributes to insulin resistance, inflammation, and oxidative stress. Metabolites derived from the gut microbiota enter the systemic circulation and influence both the liver and heart, resulting in the gut-liver-heart axis playing an important role in MAFLD. Furthermore, growing evidence suggests that insulin resistance, endothelial dysfunction, and systemic inflammation in MAFLD may contribute to an increased risk of cardiovascular disease (CVD). Additionally, the dysregulation of lipid metabolism in MAFLD may also lead to cardiac dysfunction and heart failure. Overall, the crosstalk between the liver and heart involves a complex interplay of molecular pathways that contribute to the development of CVD in patients with MAFLD. This review emphasizes the current understanding of the gut-liver-heart crosstalk as a foundation for optimizing patient outcomes with MAFLD.

The Spectrum and Impact of Metabolic Dysfunction in MAFLD: A Longitudinal Cohort Analysis of 32,683 Overweight and Obese Individuals

BACKGROUND

Metabolic associated fatty liver disease (MAFLD) was recently proposed as an alternative name change for better encapsulation of disease. However, there exists a spectrum of MAFLD where both metabolically healthy (MH) and metabolically unhealthy (MU) individuals are included. In view of limited evidence, we sought to examine the prevalence, clinical characteristics, and differences in outcomes of MH-MAFLD at the population level.

METHODS

Data were used from the United States National Health and Nutrition Examination Survey 1999 to 2018. Multivariate logistic regression analysis was used to obtain odds ratios for the estimation of events. Survival analysis was conducted with Cox regression and the Fine-Gray subdistribution model.

RESULTS

There were 32,683 overweight and obese individuals included in the analysis. In MAFLD patients, the prevalence of MH-MAFLD was 6.92% (95% confidence interval [CI], 6.58%-7.27%), and 93.08% (95% CI, 92.73%-93.42%) were considered as MU-MAFLD. Multivariate analysis found a significantly higher risk of MACE (odds ratio, 1.38; 95% CI, 1.28-1.49; P < .01), all-cause (hazard ratio, 1.24; 95% CI, 1.17-1.32; P < .01), cardiovascular disease (SHR, 1.20; 95% CI, 1.02-1.42; P = .03), and cancer mortality (SHR, 1.24; 95% CI, 1.07-1.44; P < .01) in MU-MAFLD relative to non-MAFLD. However, MH-MAFLD individuals were not associated with a statistically significant increased risk of these adverse outcomes compared with non-MAFLD. MU-MAFLD diabetics were also at a higher risk of adverse events compared with non-diabetics.

CONCLUSIONS

This study reports on the heterogeneity and spectrum of metabolic dysfunction that exists in overweight and obese MAFLD. Although MAFLD may potentially be advantageous in improving awareness and patient outcomes, there remains substantial heterogeneity within patients included in MAFLD on the basis of the underlying metabolic burden.

MAFLD might be better in identifying subjects with sarcopenia or cardiovascular risk than NAFLD: A nationwide study

BACKGROUND AND AIM

Clinical features of non-alcoholic fatty liver disease (NAFLD), but not fulfilling the diagnostic criteria of metabolic dysfunction-associated fatty liver disease (MAFLD), remain unclear. We investigated the risk of sarcopenia and cardiovascular disease (CVD) in MAFLD and non-metabolic risk (MR) NAFLD.

METHODS

Subjects were selected from the Korean National Health and Nutrition Examination Surveys 2008-2011. Liver steatosis was assessed using fatty liver index. Significant liver fibrosis was defined using fibrosis-4 index, categorized by age cut-offs. Sarcopenia was defined as the lowest quintile sarcopenia index. Atherosclerotic CVD (ASCVD) risk score > 10% was defined as high probability.

RESULTS

A total of 7248 subjects had fatty liver (137 with non-MR NAFLD, 1752 with MAFLD/non-NAFLD, and 5359 with overlapping MAFLD and NAFLD). In non-MR NAFLD group 28 (20.4%) had significant fibrosis. The risk of sarcopenia (adjusted odds ratio [aOR] = 2.71, 95% confidence index [CI] = 1.27-5.78) and high probability of ASCVD (aOR = 2.79, 95% CI = 1.23-6.35) was significantly higher in MAFLD/non-NAFLD group than in non-MR NAFLD group (all P < 0.05). The risk of sarcopenia and high probability of ASCVD was similar between subjects with and without significant fibrosis in non-MR NAFLD group (all P > 0.05). However, the risk was significantly higher in MAFLD group than in non-MR NAFLD group (aOR = 3.38 for sarcopenia and 3.73 for ASCVD; all P < 0.05).

CONCLUSIONS

The risks of sarcopenia and CVD were significantly higher in MAFLD group but did not differ according to fibrotic burden in non-MR NAFLD group. The MAFLD criteria might be better for identifying high-risk fatty liver disease than the NAFLD criteria.

Metabolic dysfunction-associated fatty liver disease and the risk of hepatocellular carcinoma

Background & Aims

The metabolic dysfunction-associated fatty liver disease (MAFLD) is a new inclusive term proposed to replace non-alcoholic fatty liver disease (NAFLD). We analysed whether hepatocellular carcinoma (HCC) risk differs by MAFLD or NAFLD status in a large sample of asymptomatic adults.

Methods

A cohort comprising 73,691 adults were followed up for the development of HCC. NAFLD was diagnosed among participants without other liver diseases (n = 65,992).

Results

Participants with MAFLD showed higher incidence of HCC than those without MAFLD (0.37 and 0.24 per 1,000 person-years, respectively; p = 0.006). However, MAFLD was not an independent factor associated with HCC in multivariable adjusted analysis (hazard ratio [HR] 1.21; 95% CI 0.92-1.60). When stratified according to presence of other liver diseases, MAFLD was not associated with HCC in participants with other liver diseases. In participants without other liver diseases, both MAFLD (adjusted HR 1.84; 95% CI 1.09-3.11) and NAFLD (adjusted HR 1.71; 95% CI 1.01-2.90) were independent factors associated with HCC. When stratified according to NAFLD and MAFLD status, there was no HCC development among participants with NAFLD only during 8,936 person-years of follow-up, but this NAFLD-only group comprised 3.4%, and the majority of participants with hepatic steatosis fulfilled both NAFLD and MAFLD criteria.

Conclusions

In patients with other chronic liver diseases, the presence of MAFLD is not independently associated with an increased risk of HCC. For those without other chronic liver diseases, MAFLD largely overlaps with NAFLD and is associated with an increased risk of HCC.

Impact and Implications

This study investigated the usefulness of newly proposed nomenclature, metabolic dysfunction-associated fatty liver disease (MAFLD), over non-alcoholic fatty liver disease (NAFLD), in terms of predicting hepatocellular carcinoma. In patients with other chronic liver diseases, the presence of MAFLD is not independently associated with an increased risk of HCC. However, for those without chronic liver disease, MAFLD largely overlaps with NAFLD and is associated with an increased risk of HCC.

The impact of concomitant metabolic dysfunction-associated fatty liver disease on adverse outcomes in patients with hepatitis B cirrhosis: a propensity score matching study

BACKGROUND AND AIMS

In cirrhotic patients, the clinical relevance of metabolic dysfunction-associated fatty liver disease (MAFLD) is unclear. We aimed to research the relationship between MAFLD and adverse clinical outcomes in patients with hepatitis B cirrhosis.

METHODS

A total of 439 patients with hepatitis B cirrhosis were enrolled. Abdominal MRI and computed tomography were used to calculate liver fat content in order to evaluate steatosis. The Kaplan-Meier method was implemented to generate survival curves. The independent risk factors for prognosis were identified by multiple Cox regression. Propensity score matching (PSM) was used to reduce the influence of confounding factors. This study explored the relevance between MAFLD and mortality, first decompensation and further decompensation.

RESULTS

In our study, most patients were decompensated cirrhosis (n = 332, 75.6%) and the ratio of decompensated cirrhosis patients in non-MAFLD to MAFLD group was 199 : 133. Compared to the non-MAFLD group, patients with MAFLD had worse liver function which mainly reflected that there were more Child-Pugh C patients and higher model for end-stage liver disease score in the MAFLD group. A total of 207 adverse clinical events occurred in the total cohort during a median follow-up of 47 months, including 45 deaths, 28 hepatocellular carcinoma, 23 first decompensation and 111 further decompensation. Cox multivariate analysis showed that MAFLD was an independent risk factor for death [hazard ratio (HR) 1.931; 95% confidence interval (CI) 1.019-3.660; P = 0.044 HR 2.645; 95% CI, 1.145-6.115; P = 0.023] and further decompensation (HR 1.859; 95% CI, 1.261-2.741; P = 0.002 HR 1.953; 95% CI, 1.195-3.192; P = 0.008) before and after PSM. In decompensated group with MAFLD, diabetes had a more significant effect on adverse prognosis than overweight or obesity and other metabolic risk factors.

CONCLUSION

In patients with hepatitis B cirrhosis, concomitant MAFLD can predict a higher risk of further decompensation and death among decompensated individuals. According to patients among MAFLD, diabetes may be a major factor in the occurrence of adverse clinical events.

Hepatic, Extra-hepatic Outcomes and Causes of Mortality in NAFLD - An Umbrella Overview of Systematic Review of Meta-Analysis

Background

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease globally. While the prevalence, impact, and causes of mortality have been described in various meta-analyses, a systematic all-encompassing umbrella review has yet to be conducted to consolidate the evidence on outcomes associated with NAFLD.

Methods

Search was conducted on Medline and Embase for meta-analysis investigating associated complications and causes of mortality in NAFLD patients. Summary estimates were presented with original units, sample size, and I2 for heterogeneity. The Assessment of Multiple Systematic Reviews 2 was employed for article selection.

Results

25 meta-analyses were included in the present review. NAFLD increased the risks of systemic complications, including cardiovascular diseases, systemic malignancies, diabetes, and chronic kidney disease. Regarding hepatic outcomes, the incidence of hepatocellular carcinoma in NAFLD was 2.39 per 100 person years (CI: 1.40 to 4.08). Individuals with NAFLD were also found to have an increased likelihood of cholangiocarcinoma (OR: 1.88, CI: 1.25 to 2.83) and gallstone disease (OR: 1.55, CI: 1.31 to 1.82) compared to individuals without NAFLD. NAFLD was associated with a higher risk of fatal and non-fatal CVD events (HR: 1.45, CI: 1.31 to 1.61) compared to individuals without NAFLD. Coronary heart disease and subclinical and clinical coronary heart disease were also significantly elevated in NAFLD individuals compared to individuals without NAFLD. Additionally, NAFLD was associated with an increased risk of all-cause mortality (HR: 1.34, CI: 1.17 to 1.54) and cardiovascular (HR: 1.30, CI: 1.08 to 1.56) but not cancer-related mortality.

Conclusion

The study summarizes high-level evidence from published meta-analyses to provide a much-needed update on the outcomes in patients with NAFLD. The significant systemic burden associated with NAFLD and impending fatty liver epidemic requires prompt action from multidisciplinary providers, policy providers, and stakeholders to reduce the burden of NAFLD.

Global epidemiology of cirrhosis - aetiology, trends and predictions

Cirrhosis is an important cause of morbidity and mortality in people with chronic liver disease worldwide. In 2019, cirrhosis was associated with 2.4% of global deaths. Owing to the rising prevalence of obesity and increased alcohol consumption on the one hand, and improvements in the management of hepatitis B virus and hepatitis C virus infections on the other, the epidemiology and burden of cirrhosis are changing. In this Review, we highlight global trends in the epidemiology of cirrhosis, discuss the contributions of various aetiologies of liver disease, examine projections for the burden of cirrhosis, and suggest future directions to tackle this condition. Although viral hepatitis remains the leading cause of cirrhosis worldwide, the prevalence of non-alcoholic fatty liver disease (NAFLD) and alcohol-associated cirrhosis are rising in several regions of the world. The global number of deaths from cirrhosis increased between 2012 and 2017, but age-standardized death rates (ASDRs) declined. However, the ASDR for NAFLD-associated cirrhosis increased over this period, whereas ASDRs for other aetiologies of cirrhosis declined. The number of deaths from cirrhosis is projected to increase in the next decade. For these reasons, greater efforts are required to facilitate primary prevention, early detection and treatment of liver disease, and to improve access to care.

Correlation of the Pediatric Metabolic Index with NAFLD or MAFLD diagnosis, and serum adipokine levels in children

INTRODUCTION

Non-alcoholic fatty liver disease (NAFLD) is characterized by ectopic fat deposition in the liver. However, a recent classification of this condition, which also integrates the presence of coexisting metabolic disorders, termed Metabolic dysfunction Associated Fatty Liver Disease (MAFLD), has been proposed. NAFLD is increasingly common in early childhood, partly due to the increase in metabolic disease in this age. Thus, studying hepatic steatosis in the metabolic context has become important in this population as well. However, NAFLD, and thus MAFLD, diagnosis in children is challenging by the lack of non-invasive diagnostic tools comparable to the gold standard of hepatic biopsy. Recent studies have reported that the Pediatric Metabolic Index (PMI) could be a marker of insulin resistance and abnormal liver enzymes, but its association with NAFLD, MAFLD, or altered adipokines in these conditions has not been reported. The aim of this study is to evaluate the correlation between PMI with the diagnosis of NAFLD or MAFLD, together with serum levels of leptin and adiponectin, in school-age children.

METHODS

A cross sectional study was carried out in two hundred and twenty-three children without medical history of hypothyroidism, genetic, or chronic diseases. Anthropometry, liver ultrasound, and serum levels of lipids, leptin, and adiponectin were evaluated. The children were classified as having NAFLD or non-NAFLD, and a subgroup of MAFLD in the NAFLD group was analyzed. The PMI was calculated by the established formulas for age and gender.

RESULTS

PMI correlated positively with the presence and severity of NAFLD (r=0.62, p<0.001 and r= 0.79, p<0.001 respectively) and with the presence of MAFLD (r=0.62; p<0.001). Also, this index correlated positively with serum leptin levels (r=0.66; p<0.001) and negatively with serum adiponectin levels (r= -0.65; p<0.001). PMI showed to be a good predictor for diagnosing NAFLD in school-age children when performing a ROC curve analysis (AUROC=0.986, p< 0.0001).

CONCLUSION

PMI could be a useful tool for the early diagnosis of NAFLD or MAFLD in children. However, future studies are necessary to establish validated cut-off points for each population.

Non-Alcoholic Fatty Liver Disease or Type 2 Diabetes Mellitus—The Chicken or the Egg Dilemma

In clinical practice, we often deal with patients who suffer from non-alcoholic fatty liver disease (NAFLD) concurrent with type 2 diabetes mellitus (T2DM). The etiopathogenesis of NAFLD is mainly connected with insulin resistance (IR) and obesity. Similarly, the latter patients are in the process of developing T2DM. However, the mechanisms of NAFLD and T2DM coexistence have not been fully elucidated. Considering that both diseases and their complications are of epidemic proportions and significantly affect the length and quality of life, we aimed to answer which of these diseases appears first and thereby highlight the need for their diagnosis and treatment. To address this question, we present and discuss the epidemiological data, diagnoses, complications and pathomechanisms of these two coexisting metabolic diseases. This question is difficult to answer due to the lack of a uniform procedure for NAFLD diagnosis and the asymptomatic nature of both diseases, especially at their beginning stages. To conclude, most researchers suggest that NAFLD appears as the first disease and starts the sequence of circumstances leading ultimately to the development of T2DM. However, there are also data suggesting that T2DM develops before NAFLD. Despite the fact that we cannot definitively answer this question, it is very important to bring the attention of clinicians and researchers to the coexistence of NAFLD and T2DM in order to prevent their consequences.

Global burden of liver cancer in males and females: Changing etiological basis and the growing contribution of NASH

BACKGROUND AND AIM

The etiology of liver diseases has changed in recent years, but its impact on the comparative burden of liver cancer between males and females is unclear. We estimated sex differences in the burden of liver cancer across 204 countries and territories from 2010 to 2019.

APPROACH AND RESULT

We analyzed temporal trends in the burden of liver cancer using the methodology framework of the 2019 Global Burden of Disease study. We estimated annual frequencies and age-standardized rates (ASRs) of liver cancer incidence, death, and disability-adjusted life-years (DALYs) by sex, country, region, and etiology of liver disease. Globally in 2019, the frequency of incident cases, deaths, and DALYs due to liver cancer were 376,483, 333,672, and 9,048,723 in males, versus 157,881, 150,904, and 3,479,699 in females. From 2010 to 2019, the incidence ASRs in males increased while death and DALY ASRs remained stable; incidence, death, and DALY ASRs in females decreased. Death ASRs for both sexes increased only in the Americas and remained stable or declined in remaining regions. In 2019, hepatitis B was the leading cause of liver cancer death in males, and hepatitis C in females. From 2010 to 2019, NASH had the fastest growing death ASRs in males and females. The ratio of female-to-male death ASRs in 2019 was lowest in hepatitis B (0.2) and highest in NASH (0.9).

CONCLUSIONS

The overall burden of liver cancer is higher in males, although incidence and death ASRs from NASH-associated liver cancer in females approach that of males.

Metabolic dysfunction associated fatty liver disease identifies subjects with cardiovascular risk better than non-alcoholic fatty liver disease

BACKGROUND AND AIMS

Cardiovascular disease (CVD) is the main cause of mortality in subjects with non-alcoholic fatty liver disease (NAFLD). We investigated the association between CVD risk and metabolic dysfunction-associated fatty liver disease (MAFLD) or NAFLD and the influence of significant liver fibrosis on the CVD risk.

METHODS

Subjects who underwent a comprehensive medical check-up were recruited (2014-2019). Significant liver fibrosis was defined using NAFLD fibrosis score, fibrosis-4 index, aspartate aminotransferase to platelet ratio index, or FibroScan-aspartate aminotransferase score. High probability of atherosclerotic CVD (ASCVD) was defined as ASCVD risk score > 10%.

RESULTS

Of the study population (n = 78 762), 27 047 (34.3%) and 24 036 (30.5%) subjects had MAFLD and NAFLD respectively. A total of 1084 (4.0%) or 921 (3.8%) subjects had previous CVD history in MAFLD or NAFLD subgroup respectively. The previous CVD history and high probability of ASCVD were significantly higher in MAFLD or NAFLD subgroup with significant liver fibrosis than in the other groups (all p < .001). In multivariable analysis, MAFLD was independently associated with previous CVD history after adjusting for confounders (adjusted odds ratio [aOR] = 1.10, p = .038), whereas NAFLD was not (all p > .05). MAFLD (aOR = 1.40) or NAFLD (aOR = 1.22) was independently associated with high probability of ASCVD after full adjustment respectively (all p < .001). Significant liver fibrosis was independently associated with previous CVD history and high probability of ASCVD after adjustment in MAFLD or NAFLD subgroup respectively (all p < .05).

CONCLUSION

MAFLD might better identify subjects with CVD risk than NAFLD. Fibrosis assessment might be helpful for detailed prognostication in subjects with MAFLD.

Causes and risk profiles of mortality among individuals with nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the United States and worldwide. Though nonalcoholic fatty liver per se may not be independently associated with an increased risk for all-cause mortality, it is associated with a number of harmful metabolic risk factors, such as type 2 diabetes mellitus, hyperlipidemia, obesity, a sedentary lifestyle, and an unhealthy diet. The fibrosis stage is a predictor of all-cause mortality in NAFLD. Mortality in individuals with NAFLD has been steadily increasing, and the most common cause-specific mortality for NAFLD is cardiovascular disease, followed by extra-hepatic cancer, liver-related mortality, and diabetes. High-risk profiles for mortality in NAFLD include PNPLA3 I148M polymorphism, low thyroid function and hypothyroidism, and sarcopenia. Achieving weight loss through adherence to a high-quality diet and sufficient physical activity is the most important predictor of improvement in NAFLD severity and the benefit of survival. Given the increasing health burden of NAFLD, future studies with more long-term mortality data may demonstrate an independent association between NAFLD and mortality.

The independent effect of exercise on biopsy-proven non-alcoholic fatty liver disease: A systematic review

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. Although previous studies have demonstrated that exercise independently reduces hepatic steatosis measured by imaging modalities in NAFLD, the effect of exercise on histological endpoints remains unclear. We aimed to conduct a systematic review of the independent effect of exercise on hepatic steatosis, steatohepatitis, and liver fibrosis as measured by histological assessment or non-invasive tests (NITs) in biopsy-proven NAFLD. A systematic literature search of PubMed, Embase, and Web of Science databases was performed using keywords related to exercise, NAFLD, and biopsy. Articles were selected based on the following inclusion criteria: (1) involved human subjects with biopsy-proven NAFLD, (2) analyzed the independent effect of exercise, (3) assessed changes in hepatic steatosis, steatohepatitis, or liver fibrosis via either histological evaluation or NITs, and (4) were original research studies. We identified a total of six studies that analyzed the independent effect of exercise on histological endpoints in biopsy-proven NAFLD. Two randomized controlled trials (RCTs) did not detect significant histological improvement following exercise interventions, while other non-randomized interventional studies showed that exercise reduces hepatocyte ballooning and liver fibrosis. In addition, five studies assessed NIT outcomes, collectively demonstrating that exercise improves hepatic steatosis measured by magnetic resonance imaging-based techniques but not serum biomarkers for steatohepatitis and liver fibrosis. Additional large RCTs and meta-analyses are warranted to investigate the independent effect of exercise on histological and clinical outcome endpoints in NAFLD.

MAFLD: How is it different from NAFLD?

"Metabolic dysfunction-associated fatty liver disease (MAFLD)" is the term suggested in 2020 to refer to fatty liver disease related to systemic metabolic dysregulation. The name change from nonalcoholic fatty liver disease (NAFLD) to MAFLD comes with a simple set of criteria to enable easy diagnosis at the bedside for the general medical community, including primary care physicians. Since the introduction of the term, there have been key areas in which the superiority of MAFLD over the traditional NAFLD terminology has been demonstrated, including for the risk of liver and extrahepatic mortality, disease associations, and for identifying high-risk individuals. Additionally, MAFLD has been adopted by a number of leading pan-national and national societies due to its concise diagnostic criterion, removal of the requirement to exclude concomitant liver diseases, and reduction in the stigma associated with this condition. The current article explores the differences between MAFLD and NAFLD diagnosis, areas of benefit, some potential limitations, and how the MAFLD terminology has opened up new fields of research.

Non-alcoholic fatty liver disease: Definition and subtypes

Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases worldwide, with a global prevalence of approximately 30%. However, the prevalence of NAFLD has been variously reported depending on the comorbidities. The rising prevalence of obesity in both the adult and pediatric populations is projected to consequently continue increasing NAFLD prevalence. It is a major cause of chronic liver disease worldwide, including cirrhosis and hepatocellular carcinoma (HCC). NAFLD has a variety of clinical phenotypes and heterogeneity due to the complexity of pathogenesis and clinical conditions of its occurrence, resulting in various clinical prognoses. In this article, we briefly described the basic definition of NAFLD and classified the subtypes based on current knowledge in this field.

Type 2 diabetes mellitus in metabolic-associated fatty liver disease vs. type 2 diabetes mellitus non-alcoholic fatty liver disease: a longitudinal cohort analysis

INTRODUCTION AND OBJECTIVES

Type 2 Diabetes Mellitus (T2DM) is comorbidity commonly presenting with fatty liver. A recently proposed definition of "metabolic associated fatty liver disease" (MAFLD) is thought to replace non-alcoholic fatty liver disease (NAFLD). Yet, despite the significant prevalence of T2DM among fatty liver, there remains limited evidence on the impact of the change in the definition of T2DM.

MATERIALS AND METHODS

The current study uses data from the United States National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018. Survival analysis was conducted with a cox regression and sub-distribution hazard ratio for competing risk events.

RESULTS

6727 patients had a diagnosis of T2DM. 4982 individuals with T2DM had MAFLD and 2032 were MAFLD(+)/NAFLD(-), while 2950 patients were MAFLD(+)/NAFLD(+). The new definition increased fatty liver diagnosis by 68.89%. Patients who were classified as MAFLD(+)/NAFLD(-) were at a higher risk of major adverse cardiovascular events, advanced fibrosis, all-cause and cardiovascular-related mortality compared to MAFLD(+)/NAFLD(+). In MAFLD(+)/NAFLD(-), viral hepatitis significantly increases the odds of advanced fibrosis (OR: 6.77, CI: 3.92 to 11.7, p < 0.001) and all-cause mortality (HR: 1.75, CI: 1.29 to 2.40, p < 0.001).

CONCLUSIONS

The identification and treatment of NAFLD in patients with T2DM is a major concern and the premature change to MAFLD results in an over-diagnosis of fatty liver, exaggerated mortality, and morbidity in patients with T2DM. The definition of MAFLD causes further heterogeneity in fatty liver disease/NAFLD.

Examining the interim proposal for name change to steatotic liver disease in the US population

BACKGROUND AND AIMS

Fatty liver is the commonest liver condition globally and traditionally associated with NAFLD. A consensus meeting was held in Chicago to explore various terminologies. Herein, we explore the proposed changes in nomenclature in a population data set from the US.

APPROACH AND RESULTS

Statistical analysis was conducted using survey-weighted analysis. Assessment of fatty liver was conducted with vibration-controlled transient elastography. A controlled attenuation parameter of 288 dB/m was used to identify hepatic steatosis. Patients were classified into nonalcoholic steatotic liver disease, alcohol-associated steatotic liver disease, and viral hepatitis steatotic liver disease. Liver stiffness measures at ≥8.8, ≥11.7, and ≥14 kPa were used to identify clinically significant fibrosis, advanced fibrosis, and cirrhosis, respectively. A total of 5102 individuals were included in the analysis. Using a survey-weighted analysis, a total of 25.43%, 6.95%, and 0.73% of the population were classified as nonalcoholic steatotic liver disease, alcohol-associated steatotic liver disease, and viral hepatitis steatotic liver disease, respectively. A sensitivity analysis at controlled attenuation parameter of 248 dB/m and fatty liver index found similar distribution. In a comparison between nonalcoholic steatotic liver disease, alcohol-associated steatotic liver disease, and viral hepatitis steatotic liver disease, there was no significant difference between the odds of advanced fibrosis and cirrhosis between groups. However, viral hepatitis steatotic liver disease individuals were found to have a significantly higher odds of clinically significant fibrosis (OR: 3.76, 95% CI, 1.27-11.14, p =0.02) compared with nonalcoholic steatotic liver disease.

CONCLUSIONS

The current analysis assessed the proposed changes based on discussions from the consensus meeting. Although the definitions are an interim analysis of discussions, steatotic liver disease respects the underlying liver etiology and reduces stigma while increasing awareness of FL among viral and alcohol-associated steatosis/steatohepatitis.

Global prevalence of non-alcoholic fatty liver disease and non-alcoholic steatohepatitis in the overweight and obese population: a systematic review and meta-analysis

BACKGROUND

The global burden of non-alcoholic fatty liver disease (NAFLD) parallels the increase in obesity rates across the world. Although overweight and obesity status are thought to be an effective indicator for NAFLD screening, the exact prevalence of NAFLD in this population remains unknown. We aimed to report the prevalence of NAFLD, non-alcoholic fatty liver (NAFL), and non-alcoholic steatohepatitis (NASH) in the overweight and obese population.

METHODS

In this systematic review and meta-analysis, we searched Medline and Embase from database inception until March 6, 2022, using search terms including but not limited to "non-alcoholic fatty liver disease", "overweight", "obesity", and "prevalence". Cross-sectional and longitudinal observational studies published after Jan 1, 2000, written in or translated into English were eligible for inclusion; paediatric studies were excluded. Articles were included if the number of NAFLD, NAFL, or NASH events in an overweight and obese population could be extracted. Summary data were extracted from published reports. The primary outcomes were the prevalence of NAFLD, NAFL, and NASH in an overweight and obese population and the prevalence of fibrosis in individuals who were overweight or obese and who had NAFLD. A meta-analysis of proportions was done with the generalised linear mixed model. This study is registered with PROSPERO (CRD42022344526).

FINDINGS

The search identified 7389 articles. 151 studies met the inclusion criteria and were included in the meta-analysis. In the pooled analysis comprising 101 028 individuals, the prevalence of NAFLD in the overweight population was 69·99% (95% CI 65·40-74·21 I²=99·10%), the prevalence of NAFL was 42·49% (32·55-53·08, I²=96·40%), and the prevalence of NASH was 33·50% (28·38-39·04, I²=95·60%). Similar prevalence estimates were reported in the obese population for NAFLD (75·27% [95% CI 70·90-79·18]; I²=98·50%), NAFL (43·05% [32·78-53·97]; I²=96·30%) and NASH (33·67% [28·45-39·31]; I²=95·60%). The prevalence of NAFLD in the overweight population was the highest in the region of the Americas (75·34% [95% CI: 67·31-81·93]; I²=99·00%). Clinically significant fibrosis (stages F2-4) was present in 20·27% (95% CI 11·32-33·62; I²= 93·00%) of overweight individuals with NAFLD and in 21·60% (11·47-36·92; I²=95·00%) of obese patients with NAFLD while 6·65% (4·35-10·01; I²=58·00%) of overweight individuals with NAFLD and 6·85% (3·85-11·90; I²=90·00%) of obese individuals with NAFLD had advanced fibrosis (stages F3-4).

INTERPRETATION

This study summarises the estimated global prevalence of NAFLD, NAFL, and NASH in overweight and obese individuals; these findings are important for improving the understanding of the global NAFLD burden and supporting disease management in the at-risk overweight and obese population.

FUNDING

None.

Correlation between thyroid function, sensitivity to thyroid hormones and metabolic dysfunction-associated fatty liver disease in euthyroid subjects with newly diagnosed type 2 diabetes

PURPOSE

To estimate the prevalence of metabolic dysfunction-associated fatty liver disease (MAFLD) and to evaluate the associations between thyroid parameters, MAFLD and liver fibrosis in euthyroid patients with newly diagnosed type 2 diabetes mellitus (T2DM).

METHODS

Overall, 776 patients with newly diagnosed T2DM and 120 subjects without diabetes were included. All the participants were euthyroid, and were categorized as non-MAFLD and MAFLD. Demographic information, biochemical parameters, and serum thyroid hormones were collected. The thyroid hormone sensitivity indices were calculated. MAFLD was defined according to abdominal ultrasound and clinical manifestations. Noninvasive fibrosis indices were calculated to identify advanced liver fibrosis.

RESULTS

The prevalence of MAFLD was significantly higher in patients with T2DM than in subjects without diabetes. Levels of free triiodothyronine (FT3) and FT3 to free thyroxine (FT4) ratio were significantly higher in subjects with MAFLD. In patients with T2DM, levels of thyroid stimulating hormone (TSH), Thyroid feedback quantile-based index (TFQI_FT3) calculated using FT3 and TSH, thyrotroph T3 resistance index (TT3RI) and thyrotroph T4 resistance index (TT4RI) were significantly higher in subjects with MAFLD. The prevalence of MAFLD increased with the rise of FT3, FT3/FT4, TSH, and sensitivity to thyroid hormone indices (TFQI_FT3, TT3RI, and TT4RI). But significant correlations were not found between thyroid hormones, sensitivity to thyroid hormones and MAFLD, after adjustment for BMI and HOMA-IR. The incidence of advanced fibrosis tended to increase as the rise of TSH and sensitivity to thyroid hormone indices (TFQI_FT3, TT3RI, TT4RI, and TSHI).

CONCLUSION

MAFLD was prevalent in euthyroid patients with newly diagnosed T2DM. Higher normal FT3, TSH and impaired sensitivity to thyroid hormones are associated with increased incidence of MAFLD, being dependent on other metabolic factors.

The relationship between metabolic dysfunction-associated fatty liver disease and low muscle mass in an asymptomatic Korean population

BACKGROUND

Metabolic (dysfunction)-associated fatty liver disease (MAFLD) emphasizes the metabolic dysfunction in nonalcoholic fatty liver disease (NAFLD). Although the relationship between low muscle mass and NAFLD has been suggested, the effect of MAFLD on low muscle mass is yet to be investigated. In this study, we examined the relationship between MAFLD and low muscle mass in an asymptomatic Korean population.

METHODS

Examinees who underwent FibroScan® and bioelectrical impedance analyses on the same day during the period of June 2017 to December 2019 were included. Hepatic steatosis was diagnosed using controlled attenuation parameter (CAP) with two cut-off values of 248 and 294 dB/m. Low muscle mass was defined based on appendicular skeletal muscle mass/body weight (wt) or body mass index (BMI) ratios of two standard deviations below the sex-specific mean for healthy young adults. Subjects were divided into four subgroups: diabetic MAFLD (presence of diabetes mellitus [DM]), metabolic dysfunction (MD) MAFLD (≥2 metabolic abnormalities without DM), overweight MAFLD (overweight/obese without DM and <2 metabolic abnormalities) and no MAFLD.

RESULTS

Among all of the 6414 subjects (mean 53.9 years of age; 85.4% male), the prevalence of MAFLD was 49.9% and 22.7% for CAP cut-off values of 248 and 294 dB/m, respectively. In the multivariate analysis, MAFLD was associated with an increased risk of both low muscle mass_wt (odds ratio [OR] 1.80, 95% confidence interval [CI] 1.38-2.35, P < 0.001) and low muscle mass_BMI (OR 1.31, 95% CI 1.01-1.70, P = 0.042). The risk of low muscle mass_wt and low muscle mass_BMI increased the most in the diabetic MAFLD subgroup compared with the no-MAFLD group (OR 2.11, 95% CI 1.51-2.96, P < 0.001 and OR 1.51, 95% CI 1.08-2.13, P = 0.017). There was an increased risk of low muscle mass_wt in the MD MAFLD subgroup (OR 1.73, 95% CI 1.31-2.28, P < 0.001). Comparable results were observed when the CAP cut-off value of 294 dB/m was applied.

CONCLUSIONS

The presence of MAFLD is significantly associated with increased risk of low muscle mass with varying risks according to the MAFLD subgroups. Clinicians should be aware of the differentiated risk of low muscle mass across the subgroups of MAFLD.

Association between flavonoid and subclasses intake and metabolic associated fatty liver disease in U.S. adults: Results from National Health and Nutrition Examination Survey 2017-2018

BACKGROUND

Metabolic associated fatty liver disease (MAFLD) formerly known as non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. Flavonoid is considered a promising candidate for metabolic disease prevention although few studies have explored the relationship between flavonoid intake and MAFLD.

PURPOSE

To assess the relationship between flavonoid intake and MAFLD prevalence in the U.S. adult population.

MATERIALS AND METHODS

The data of this cross-sectional study was obtained from National Health and Nutrition Examination Survey (NHANES) and Food and Nutrient Database for Dietary Studies (FNDDS) 2017-2018. Flavonoid and subclasses intake was assessed by two 24h recalls. MAFLD was diagnosed according to the consensus definitions. Multivariate logistic regression model was performed to examine the association between flavonoid intake and MAFLD with adjustments for confounders.

RESULTS

A total of 4,431 participants were included in this cross-sectional analysis. MAFLD had a weighted prevalence of 41.93% and was not associated with total flavonoid intake. A higher anthocyanin and isoflavone intake, on the other hand, was associated with a lower prevalence of MAFLD. The protective effect of higher anthocyanin intake was significant among male, Non-Hispanic White, and Non-Hispanic Asia participants. Higher isoflavone intake was associated with a lower risk of MAFLD in participants of younger (age < 50), Non-Hispanic Black, Non-Hispanic Asia, and higher HEI-2015 scores compared with the lowest quartile of isoflavone intake. Stratified analysis showed that compared with the lowest quartile of anthocyanin intake, the effect of anthocyanin intake on MAFLD varied by racial groups (P _interaction = 0.02). A positive correlation existed between HDL and anthocyanidin intake (P = 0.03), whereas a negative correlation existed between FPG and isoflavone intake (P = 0.02).

CONCLUSION

MAFLD was adversely linked with flavonoid subclasses, anthocyanin and isoflavone. This modifiable lifestyle provides a potential opportunity to prevent MAFLD. These findings promote future research into the links and mechanisms between anthocyanin and isoflavone intake and MAFLD.

Forecasted 2040 global prevalence of nonalcoholic fatty liver disease using hierarchical bayesian approach

BACKGROUND/AIMS

Due to increases in obesity and type 2 diabetes, the prevalence of nonalcoholic fatty liver disease (NAFLD) has also been increasing. Current forecast models may not include non-obese NAFLD. Here, we used the Bayesian approach to forecast the prevalence of NAFLD through the year 2040.

METHODS

Prevalence data from 245 articles involving 2,699,627 persons were used with a hierarchical Bayesian approach to forecast the prevalence of NAFLD through 2040. Subgroup analyses were performed for age, gender, presence of metabolic syndrome, region, and smoking status. Sensitivity analysis was conducted for clinical setting and study quality.

RESULTS

The forecasted 2040 prevalence was 55.7%, a three-fold increase since 1990 and a 43.2% increase from the 2020 prevalence of 38.9%. The estimated average yearly increase since 2020 was 2.16%. For those aged <50 years and ≥50 years, the 2040 prevalence were not significantly different (56.7% vs. 61.5%, P=0.52). There was a significant difference in 2040 prevalence by sex (males: 60% vs. 50%) but the trend was steeper for females (annual percentage change: 2.5% vs. 1.5%, P=0.025). There was no difference in trends overtime by region (P=0.48). The increase rate was significantly higher in those without metabolic syndrome (3.8% vs. 0.84%, P=0.003) and smokers (1.4% vs. 1.1%, P=0.011). There was no difference by clinical/community setting (P=0.491) or study quality (P=0.85).

CONCLUSION

By 2040, over half the adult population is forecasted to have NAFLD. The largest increases are expected to occur in women, smokers, and those without metabolic syndrome. Intensified efforts are needed to raise awareness of NAFLD and to determine long-term solutions addressing the driving factors of the disease.

The clinical impact of an extra virgin olive oil enriched mediterranean diet on metabolic syndrome: Lights and shadows of a nutraceutical approach

For years it has been established that the only truly effective treatment of metabolic syndrome (MS) is lifestyle modification to prevent its cardiovascular (e.g., coronary artery disease and atherosclerosis), metabolic (e.g., diabetes mellitus), and hepatic (e.g., steatosis and non-alcoholic steatohepatitis) complications. The focal points of this approach are to increase physical activity and intake of a diet characterized by high quantities of fruits, vegetables, grains, fish, and low-fat dairy products, the so called mediterranean diet (MD); however, the added value of MD is the presence of extra virgin olive oil (EVOO), a healthy food with a high content of monounsaturated fatty acids, especially oleic acid, and variable concentrations (range 50–800 mg/kg) of phenols (oleuropein, ligstroside, and oleocanthal, and their derivatives, phenolic alcohols, such as hydroxytyrosol and tyrosol). Phenolic compounds not only determine EVOO’s main organoleptic qualities (oxidative stability, specific flavor, and taste features) but, theoretically, make it a source of antioxidant, anti-inflammatory, insulin-sensitizing, cardioprotective, antiatherogenic, neuroprotective, immunomodulatory, and anticancer activity. Although many studies have been carried out on EVOO’s clinical effects and attention toward this dietary approach (healthy and palatable food with strong nutraceutical activity) has become increasingly pressing, there are still many dark sides to be clarified, both in terms of actual clinical efficacy and biochemical and molecular activity. Thus, we reviewed the international literature, trying to show the state of the art about EVOO’s clinical properties to treat MS (along with correlated complications) and the future prospective of its nutraceutical use.

Effects of Dietary Nutrients on Fatty Liver Disease Associated With Metabolic Dysfunction (MAFLD): Based on the Intestinal-Hepatic Axis

Non-alcoholic fatty liver disease (NAFLD) has recently become the most common liver disease with a global prevalence of over 25% and is expected to increase. Recently, experts have reached a consensus that “fatty liver disease associated with metabolic dysfunction or MAFLD” may be a more appropriate and inclusive definition than NAFLD. Like the former name NAFLD, MAFLD, as a manifestation of multiple system metabolic disorders involving the liver, has certain heterogeneity in its pathogenesis, clinical manifestations, pathological changes and natural outcomes. We found that there is a delicate dynamic balance among intestinal microflora, metabolites and host immune system to maintain a healthy intestinal environment and host health. On the contrary, this imbalance is related to diseases such as MAFLD. However, there are no clear studies on how dietary nutrients affect the intestinal environment and participate in the pathogenesis of MAFLD. This review summarizes the interactions among dietary nutrients, intestinal microbiota and MAFLD in an attempt to provide evidence for the use of dietary supplements to regulate liver function in patients with MAFLD. These dietary nutrients influence the development and progression of MAFLD mainly through the hepatic-intestinal axis by altering dietary energy absorption, regulating bile acid metabolism, changing intestinal permeability and producing ethanol. Meanwhile, the nutrients have the ability to combat MAFLD in terms of enriching abundance of intestinal microbiota, reducing Firmicutes/Bacteroidetes ratio and promoting abundance of beneficial gut microbes. Therefore, family therapy with MAFLD using a reasonable diet could be considered.