Nonheavy Drinking and Worsening of Noninvasive Fibrosis Markers in Nonalcoholic Fatty Liver Disease: A Cohort Study

Characteristics and long-term mortality of individuals with MASLD, MetALD, and ALD, and the utility of SAFE score

Background & Aims

The new nomenclature of steatotic liver disease (SLD) was recently launched with sub-classifications of metabolic dysfunction-associated SLD (MASLD), MASLD with increased alcohol intake (MetALD), and alcohol-related liver disease (ALD). Herein, we aimed to evaluate the characteristics and long-term outcomes associated with these subgroups and the utility of non-invasive biomarkers.

Methods

Using NHANES III (the third National Health and Nutrition Examination Survey) and linked mortality data, all adult participants with available ultrasonographic liver steatosis status were included. Those with viral hepatitis, incomplete data on alcohol consumption, cardiometabolic risk, and missing data that hindered Steatosis-associated Fibrosis Estimator (SAFE) score calculation were excluded. The characteristics of those without SLD (no steatosis on ultrasound), MASLD, MetALD, and ALD were compared. Overall survival (OS) was determined and SAFE score strata were applied to SLD subgroups.

Results

A total of 9,939 participants were eligible; 64% had no SLD, while 30%, 2.3%, and 1% had MASLD, MetALD, and ALD, respectively. A higher proportion of men, as well as active smokers, was observed in the MetALD and ALD groups compared to the MASLD group. Diabetes was more prevalent in the MASLD group than in the MetALD and ALD groups. The ALD subgroup had significantly lower OS than the MASLD group (p = 0.004), but the MetALD did not (p = 0.165). SAFE score strata meaningfully differentiated OS of all SLD subgroups.

Conclusions

MASLD accounted for the largest proportion of SLD. MetALD shared the characteristics of both MASLD and ALD. The ALD subgroup had a significantly lower OS than the MASLD subgroup but there was no difference between MetALD and MASLD. The SAFE score can be used to stratify long-term outcomes in all SLD subgroups.

Impact and implications

"Steatotic liver disease (SLD)" is a recently introduced term covering three subgroups: MASLD (metabolic dysfunction-associated SLD), MetALD (MASLD with increased alcohol intake), and ALD (alcohol-related liver disease). We explored the characteristics and outcomes of these subgroups among the US population. We found that MASLD was far more common than MetALD and ALD, but all subgroups shared cardiometabolic risk factors. The ALD subgroup has the worst survival, pointing to the synergistic effect of alcohol and metabolic dysfunction. In addition, the SAFE (Steatosis-associated Fibrosis Estimator) score might be a useful non-invasive test to stratify long-term risk in all three SLD subgroups.

Dual-etiology MAFLD: the interactions between viral hepatitis B, viral hepatitis C, alcohol, and MAFLD

Metabolic dysfunction-associated fatty liver disease (MAFLD) and viral hepatitis due to chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infection are common liver diseases worldwide. Excessive alcohol consumption and alcoholic liver disease (ALD) are also emerging health problems. Therefore, in clinical practice, we may encounter subjects with dual etiology of liver diseases such as coexisting MAFLD/HBV, MAFLD/HCV, and MAFLD/ALD. In this review, we summarize the epidemiology, clinical features, and mutual interactions of MAFLD with coexisting HBV, HCV, or ALD. The impact of MAFLD on the progression of liver diseases and treatment outcomes in patients with chronic viral hepatitis and the clinical questions to be addressed regarding dual MAFLD and ALD are also discussed.

Epidemiology and diagnosis of metabolic dysfunction-associated fatty liver disease

The most common chronic liver illness worldwide is metabolic dysfunction linked to fatty liver disease (MAFLD), which is poorly understood by doctors and patients. Many people with this disease develop steatohepatitis, cirrhosis and its consequences, as well as extrahepatic manifestations; these conditions are particularly common if they are linked to diabetes mellitus or obesity. A breakthrough with numerous benefits is the switch from NAFLD to MAFLD in terms of terminology and methodology. The diagnosis of MAFLD is based on affirmative criteria; unlike NAFLD, it is no longer based on exclusion. The diagnosis of MAFLD and the evaluation of steatosis and fibrosis is achieved using liver biopsy and non-invasive laboratory or radiographic techniques. We briefly address the most recent developments in MAFLD epidemiology and diagnosis.

Viral antibody response predicts morbidity and mortality in alcohol-associated hepatitis

BACKGROUND AND AIMS

Alcohol-associated hepatitis (AH) is associated with very high mortality despite abstinence from alcohol; up to 40% of patients die within 6 months of diagnosis. Patients with AH are especially prone to infections, which can lead to multiorgan dysfunction and poorer prognosis.

APPROACH AND RESULTS

We performed comprehensive serological profiling of the viral and bacterial infection history of 36 healthy controls, 48 patients with alcohol use disorder, and 224 patients with AH from 2 multicenter observational studies. We used systematic viral and bacterial epitope scanning by VirScan, a phage-display immunoprecipitation and sequencing technology that detects the peptides recognized by antibodies in patient sera, to comprehensively analyze antiviral and antibacterial antibodies and identify serologic biomarkers to predict patient outcomes. We found significant differences in the serological profiles of the 3 populations. The number of serum antibody epitopes in patients with alcohol use disorder during abstinence was increased compared with during active alcohol use. A decreased number and diversity of viral and bacterial antibody targets were detected in the sera of patients with AH, particularly those with a higher Child-Pugh score. In patients with AH, a decrease in the serum antiviral, but not antibacterial, antibody repertoire was associated with decompensation and mortality. Ninety-day mortality in AH could be predicted using a serum viral epitope signature.

CONCLUSIONS

Abstinence from alcohol is associated with a significant increase in serum viral and bacterial antibody response. Decreased serum antiviral antibody repertoire is predictive of decompensation of liver disease and mortality in patients with AH.

Nonalcoholic Fatty Liver Disease and Cardiovascular Disease: Causation or Association

Nonalcoholic fatty liver disease (NAFLD) is a disease process that is gaining increasing recognition. The global prevalence of NAFLD is increasing in parallel with growing rates of risk factors for NAFLD such as hypertension, obesity, diabetes, and metabolic syndrome. NAFLD has been referred to as a risk factor for cardiovascular disease (CVD). As CVD is the leading cause of morbidity and mortality worldwide, there are constant efforts to describe and alleviate its risk factors. Although there is conflicting data supporting NAFLD as a causative or associative factor for CVD, NAFLD has been shown to be associated with structural, electrical, and atherosclerotic disease processes of the heart. Shared risk factors and pathophysiologic mechanisms between NAFLD and CVD warrant further explication. Pathologic mechanisms such as endothelial dysfunction, oxidative stress, insulin resistance, genetic underpinnings, and gut microbiota dysregulation have been described in both CVD and NAFLD. The mainstay of treatment for NAFLD is lifestyle intervention including physical exercise and hypocaloric intake in addition to bariatric surgery. Investigations into various therapeutic targets to alleviate hepatic steatosis and fibrosis by way of maintaining the balance between lipid synthesis and breakdown. A major obstacle preventing the success of many pharmacologic approaches has been the effects of these medications on CVD risk. The future of pharmacologic treatment of NAFLD is promising as effective medications with limited CVD harm are being investigated.

Impact of alcohol consumption on metabolic dysfunction-associated fatty liver disease development and remission: A longitudinal cohort study

BACKGROUND

The influence of alcohol intake on metabolic dysfunction-associated fatty liver disease (MAFLD) development and remission remains unclear; thus, we aimed to investigate their longitudinal associations.

METHODS

This observational cohort study included 6349 patients who underwent more than two health check-ups over >2 years between April 2013 and March 2021. Generalized estimation equations were used to analyse the longitudinal associations between changes in alcohol intake and MAFLD according to repeated measures at baseline and the most recent stage.

RESULTS

The MAFLD development and remission rates were 20.4 and 5.1 and 9.1 and 4.7% in men and women, respectively. Although alcohol consumption was not a significant factor for MAFLD development, consuming 0.1-69.9 g/week (odds ratio [OR]: 0.672, 95% confidence interval [CI]: 0.469-0.964, p < .05) and ≥280 g/week were significant factors for MAFLD development in males (OR: 1.796, 95% CI: 1.009-3.196, p < .05) and females (OR: 16.74, 95% CI: 3.877-72.24, p < .001). Regardless of quantity and frequency, alcohol consumption was not a significant factor for MAFLD remission. Several noninvasive liver fibrosis scores were significantly associated with alcohol intake quantity and frequency in males with MAFLD development and remission (p < .05). The nonalcoholic fatty liver disease fibrosis score differed significantly between males with and without reduced alcohol intake (p < .05) who showed MAFLD remission.

CONCLUSIONS

Although the influence of alcohol intake on MAFLD development and remission differed, alcohol consumption was not beneficial for MAFLD remission in either sex. Alcohol intake reduction or cessation is recommended to prevent liver fibrosis, even in those who achieve MAFLD remission.

Phenotypes of Metabolic Dysfunction-Associated Steatotic Liver Disease-Associated Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) typically develops as a consequence of liver cirrhosis, but HCC epidemiology has evolved drastically in recent years. Metabolic dysfunction-associated steatotic liver disease (MASLD), including metabolic dysfunction-associated steatohepatitis, has emerged as the most common chronic liver disease worldwide and a leading cause of HCC. A substantial proportion of MASLD-associated HCC (MASLD-HCC) also can develop in patients without cirrhosis. The specific pathways that trigger carcinogenesis in this context are not elucidated completely, and recommendations for HCC surveillance in MASLD patients are challenging. In the era of precision medicine, it is critical to understand the processes that define the profiles of patients at increased risk of HCC in the MASLD setting, including cardiometabolic risk factors and the molecular targets that could be tackled effectively. Ideally, defining categories that encompass key pathophysiological features, associated with tailored diagnostic and treatment strategies, should facilitate the identification of specific MASLD-HCC phenotypes. In this review, we discuss MASLD-HCC, including its epidemiology and health care burden, the mechanistic data promoting MASLD, metabolic dysfunction-associated steatohepatitis, and MASLD-HCC. Its natural history, prognosis, and treatment are addressed specifically, as the role of metabolic phenotypes of MASLD-HCC as a potential strategy for risk stratification. The challenges in identifying high-risk patients and screening strategies also are discussed, as well as the potential approaches for MASLD-HCC prevention and treatment.

Role of Neutrophils in the Development of Steatotic Liver Disease

This review explores the biological aspects of neutrophils, their contributions to the development of steatotic liver disease, and their potential as therapeutic targets for the disease. Although alcohol-associated and metabolic dysfunction-associated liver diseases originate from distinct etiological factors, the two diseases frequently share excessive lipid accumulation as a common contributor to their pathogenesis, thereby classifying them as types of steatotic liver disease. Dysregulated lipid deposition in the liver induces hepatic injury, triggering the activation of the innate immunity, partially through neutrophil recruitment. Traditionally recognized for their role in microbial clearance, neutrophils have recently garnered attention for their involvement in sterile inflammation, a pivotal component of steatotic liver disease pathogenesis. In conclusion, technological innovations, including single-cell RNA sequencing, have gradually disclosed the existence of various neutrophil subsets; however, how the distinct subsets of neutrophil population contribute differentially to the development of steatotic liver disease remains unclear.

Mild-moderate alcohol consumption and diabetes are associated with liver fibrosis in patients with biopsy-proven MASLD

Background

It is unclear whether patients with metabolic dysfunction-associated steatotic liver disease (MASLD) are allowed variable low levels of alcohol. This study aimed to evaluate the effect of mild-moderate alcohol consumption on the biochemical and histological characteristics of patients with MASLD.

Methods

Alcohol consumption was assessed in 713 patients with steatotic liver disease (SLD) who underwent liver biopsy. Non-drinking, mild-moderate drinking, and excessive drinking were defined as 0 g/day, 1-<20 g/day, and >20 g/day for women and 0 g/day, 1-<30 g/day, and >30 g/day for men, respectively. Liver biopsies were scored according to the NASH CRN system.

Results

A total of 713 participants (median age 39.0 years and 77.1% male) with biopsy-proven SLD were enrolled, including 239 nondrinkers, 269 mild-moderate drinkers and 205 excessive drinkers. Excessive drinking was associated with increased risks for lobular inflammation and liver fibrosis compared to nondrinkers and mild-moderate drinkers. Compared with non-drinkers, mild-moderate drinkers had significantly lower odds for steatosis (OR = 0.60, 95% CI = 0.38-0.93, p = 0.025), hepatocellular ballooning (OR = 0.52, 95% CI = 0.29-0.91, p = 0.020) and fibrosis (OR = 0.50, 95% CI = 0.31-0.81, p = 0.005). However, in non-excessive drinkers with type 2 diabetes mellitus (T2DM), there was no association between mild-moderate alcohol consumption and liver fibrosis (OR = 0.562, 95% CI = 0.207-1.530, p = 0.257).

Conclusions

Mild-moderate alcohol consumption might be protective against liver fibrosis in MASLD patients, which is modified by the presence of T2DM. However, further longitudinal studies are needed to determine the effect of ongoing alcohol consumption on disease severity.

Low-to-moderate alcohol consumption is associated with increased fibrosis in individuals with metabolic dysfunction-associated steatotic liver disease

BACKGROUND & AIMS

Both metabolic dysfunction and alcohol consumption cause steatotic liver disease (SLD). The distinction between metabolic dysfunction-associated SLD (MASLD) and MetALD categories is based on arbitrary thresholds of alcohol intake. Thus, we assessed the impact of different levels of alcohol consumption on SLD severity and their interaction with metabolic comorbidities.

METHODS

We performed a population-based study with transient elastography (FibroScan®) data from participants in Spain (derivation cohort) and the US (validation cohort). A controlled attenuation parameter ≥275 dB/m was used to define SLD. At least one cardiometabolic risk factor was required to define MASLD. Among patients with MASLD, low alcohol consumption was defined as an average of 5-9 drinks/week, moderate consumption as 10-13 drinks/week for females and 10-20 drinks/week for males, and increased alcohol intake (MetALD) as 14-35 drinks/week for females and 21-42 drinks/week for males. Significant fibrosis was defined as a liver stiffness measurement ≥8 kPa and at-risk metabolic dysfunction-associated steatohepatitis (MASH) as a FAST score ≥0.35.

RESULTS

The derivation cohort included 2,227 individuals with MASLD (9% reported low, 14% moderate alcohol consumption) and 76 cases with MetALD. Overall prevalences of significant fibrosis and at-risk MASH were 7.6% and 14.8%, respectively. In the multivariable analysis, alcohol consumption was independently associated with significant fibrosis and at-risk MASH. A dose-dependent increase in the prevalence of significant fibrosis and at-risk MASH was observed between the number of drinks/week and the number of cardiometabolic factors. The validation cohort included 1,732 participants with MASLD, of whom 17% had significant fibrosis and 13% at-risk MASH. This cohort validated the association between moderate intake and MASLD at risk of progression (odds ratio 1.69, 95% CI 1.06-2.71).

CONCLUSIONS

Moderate alcohol intake is commonly seen in MASLD and increases the risk of advanced disease to a level similar to that observed in MetALD.

IMPACT AND IMPLICATIONS

Metabolic risk factors such as overweight, diabetes or dyslipidemia, and alcohol consumption can cause liver disease. These factors frequently coexist, but their joint effects on liver fibrosis remain uncertain. In this study, we have analyzed individuals from the general population with MASLD (metabolic dysfunction-associated steatotic liver disease) enrolled in Spain and the US. We show that moderate alcohol consumption has a supra-additive effect with metabolic risk factors, exponentially increasing the risk of liver fibrosis. These results suggest that there are no safe limits of daily alcohol intake in patients with unhealthy metabolic status and MASLD.

Changing landscape of alcohol-associated liver disease in younger individuals, women, and ethnic minorities

Alcohol use is the most important determinant of the development of alcohol-associated liver disease (ALD) and of predicting long-term outcomes in those with established liver disease. Worldwide, the amount, type, and pattern of use of alcohol vary. Alcohol use and consequent liver disease have been increasing in certain ethnic groups especially Hispanics and Native Americans, likely due to variations in genetics, cultural background, socio-economic status, and access to health care. Furthermore, the magnitude and burden of ALD have been increasing especially in the last few years among females and young adults who are at the prime of their productivity. It is critical to recognize the problem and care for these patients integrating cultural aspects in liver clinics. At the federal level, a societal approach is needed with the implementation of public health policies aiming to reduce alcohol consumption in the community. By addressing these challenges and promoting awareness, we can strive to reduce the burden of ALD, especially in high-risk demographic groups to improve their long-term health outcomes. Finally, we need studies and quality research examining these changing landscapes of demographics in ALD as a basis for developing therapeutic targets and interventions to reduce harmful drinking behaviours in these high-risk demographic groups.

Metabolic dysfunction-associated steatotic liver disease: Evolution of the final terminology

The medical term nonalcoholic fatty liver disease (NAFLD) was coined in 1986 for a condition that has since become the most prevalent liver disorder worldwide. In the last 3 years, the global professional community launched 2 consecutive efforts to purge NAFLD from the medical dictionary and recommended new terms based on disease pathophysiology rather than distinction from similar conditions featuring liver steatosis. A consensus by renowned clinical scholars primarily residing in the Asian-Pacific region introduced metabolic dysfunction-associated fatty liver disease (MAFLD) as a new name to replace NAFLD in 2020. In 2023, a nomenclature and classification resulting in the term metabolic dysfunction-associated steatotic liver disease (MASLD) was developed by a large expert panel under the auspices of leading liver societies from Europe and Americas. These marked and rapid shifts in nomenclature have garnered the attention of many researchers and clinicians across the globe due to the multilevel impact of a frequent and potentially progressive chronic liver disease in both adult and pediatric populations. The proposed terminologies differ in several ways but they have more in common than differences. They both capture key features of liver disease associated with cardiometabolic risk factors and with significant impact on all-cause and liver-related mortality. The framework of MASLD has incorporated many innovative aspects of MAFLD and while several conceptual disparities remain a work in progress, global efforts should focus on new insights into disease pathogenesis, outcome trajectories, prevention, and treatment. Here, some of these challenges are discussed to facilitate this process.

Extent to which weight loss contributes to improving metabolic dysfunction-associated and metabolic and alcohol related/associated steatotic liver disease: a study on Japanese participants undergoing health checkups

Introduction

The incidence of steatotic liver disease has increased in recent years. Thus, steatotic liver disease is a major public health issue in Japan. This study investigated the association between weight reduction and the remission of metabolic dysfunction-associated steatotic liver disease (MASLD)/Metabolic and alcohol related/associated liver disease (MetALD) in Japanese individuals undergoing health checkups.

Methods

This retrospective observational study included 8,707 Japanese patients with MASLD/MetALD who underwent health checkups from May 2015 to March 2023. The participants were monitored for its remission at their subsequent visit. MASLD was diagnosed on abdominal ultrasonography and based on the presence of at least one of five metabolic abnormalities. The impact of body mass index (BMI) reduction on MASLD/MetALD remission was assessed via logistic regression analysis and using receiver operating characteristic curves.

Results

Logistic regression analysis revealed that weight loss was significantly associated with MASLD/MetALD remission. Other factors including exercise habits and reduced alcohol consumption were significant predictors of MASLD/MetALD remission in the overall cohort and in male patients. The optimal BMI reduction cutoff values for MASLD/MetALD remission were 0.9 kg/m2 and 4.0% decrease in the overall cohort, 0.85 kg/m2 and 3.9% decrease in males, and 1.2 kg/m2 and 4.5% decrease in females. In participants with a BMI of 23 kg/m2, the cutoff values were 0.75 kg/m2 and 2.7% BMI reduction.

Discussion

Weight reduction plays an important role in both MASLD and MetALD remission among Japanese individuals. That is, targeting specific BMI reduction is effective. This underscores the importance of targeted weight management strategies in preventing and managing MASLD/MetALD in the Japanese population.

Effect of Low-Dose Alcohol Consumption on Chronic Liver Disease

Although alcohol is one of the most important etiologic agents in the development of chronic liver disease worldwide, also recognized as a promoter of carcinogenesis, several studies have shown a beneficial effect of moderate consumption in terms of reduced cardiovascular morbidity and mortality. Whether this benefit is also present in patients with liver disease due to other causes (viral, metabolic, and others) is still debated. Although there is no clear evidence emerging from guidelines and scientific literature, total abstention from drinking is usually prescribed in clinical practice. In this review, we highlight the results of the most recent evidence on this controversial topic, in order to understand the effect of mild alcohol use in this category of individuals. The quantification of alcohol intake, the composition of the tested populations, and the discrepancy between different works in relation to the outcomes represent important limitations emerging from the scientific literature. In patients with NAFLD, a beneficial effect is demonstrated only in a few works. Even if there is limited evidence in patients affected by chronic viral hepatitis, a clear deleterious effect of drinking in determining disease progression in a dose-dependent manner emerges. Poor data are available about more uncommon pathologies such as hemochromatosis. Overall, based on available data, it is not possible to establish a safe threshold for alcohol intake in patients with liver disease.

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

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

Alcohol consumption, alcohol use disorder and organ transplantation

In the present experience we have evaluated the link alcohol consumption/alcohol use disorder (AUD) and organ transplantation (OT) in order to provide adequate suggestions. The data used for the preparation of these recommendations are based on a detailed analysis of the scientific literature published before August 31, 2022 (Web of Science, Scopus, Google Scholar). Furthermore, in the process of developing this work, we consulted the guidelines/position papers of the scientific societies. With regard to the liver transplantation, there are position papers/guidelines that clearly define indications and contraindications for including the AUD patient in the transplant list. One of the major difficulties in this area is psychosocial assessment which can be influenced by stigma. To solve this problem, it is necessary to use objective tools. However, this assessment should be carried out after providing the patient and family adequate tools to be able to create or recreate reliable socio-family support. This behavior should also be used in the case of other OTs. For the latter, however, adequate guidelines must be created which at the moment do not exist or if there are, as in the case of heart transplantation, they are not sufficient. Even in the absence of obvious alcohol addiction, it is recommended to use alcohol use disorder identification test and to include the addiction specialist in the multidisciplinary transplant team. Besides, providing family members with the tools necessary to better support the patient is essential. They are patients with alcohol use disorder/ possible presence of psychopathological manifestations and alcohol-related pathology (cirrhosis, cardiomyopathy, liver-kidney disfunction, etc.). A cardiovascular and oncologic surveillance post-OT is recommended. For the selection of patients to be included in the list for non-LT (heart, lung, kidney, multivisceral, etc.) it is mandatory to include the diagnosis and treatment of AUDs in the guidelines. What has already been indicated for LT may be useful. Timing of alcoholic abstention in relation to clinical severity, optimal psychosocial activity, anticraving therapy in relation to the type of underlying disease and clinical severity. Close collaboration between scientific societies is required to better manage AUD patients who need OT.

The intersection between alcohol-related liver disease and nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) and alcohol-related liver disease (ALD) are the leading causes of chronic liver disease worldwide. NAFLD and ALD share pathophysiological, histological and genetic features and both alcohol and metabolic dysfunction coexist as aetiological factors in many patients with hepatic steatosis. A diagnosis of NAFLD requires the exclusion of significant alcohol consumption and other causes of liver disease. However, data suggest that significant alcohol consumption is often under-reported in patients classified as having NAFLD and that alcohol and metabolic factors interact to exacerbate the progression of liver disease. In this Review, we analyse existing data on the interaction between alcohol consumption and metabolic syndrome as well as the overlapping features and differences in the pathogenesis of ALD and NAFLD. We also discuss the clinical implications of the coexistence of alcohol consumption, of any degree, in patients with evidence of metabolic derangement as well as the use of alcohol biomarkers to detect alcohol intake. Finally, we summarize the evolving nomenclature of fatty liver disease and describe a recent proposal to classify patients at the intersection of NAFLD and ALD. We propose that, regardless of the presumed aetiology, patients with fatty liver disease should be evaluated for both metabolic syndrome and alcohol consumption to enable better prognostication and a personalized medicine approach.

Brazilian evidence-based guideline for screening, diagnosis, treatment, and follow-up of metabolic dysfunction-associated steatotic liver disease (MASLD) in adult individuals with overweight or obesity: A joint position statement from the Brazilian Society of Endocrinology and Metabolism (SBEM), Brazilian Society of Hepatology (SBH), and Brazilian Association for the Study of Obesity and Metabolic Syndrome (Abeso)

Introduction

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as Nonalcoholic fatty liver disease (NAFLD), is one of the most common hepatic diseases in individuals with overweight or obesity. In this context, a panel of experts from three medical societies was organized to develop an evidence-based guideline on the screening, diagnosis, treatment, and follow-up of MASLD.

Material and methods

A MEDLINE search was performed to identify randomized clinical trials, meta-analyses, cohort studies, observational studies, and other relevant studies on NAFLD. In the absence of studies on a certain topic or when the quality of the study was not adequate, the opinion of experts was adopted. Classes of Recommendation and Levels of Evidence were determined using prespecified criteria.

Results

Based on the literature review, 48 specific recommendations were elaborated, including 11 on screening and diagnosis, 9 on follow-up,14 on nonpharmacologic treatment, and 14 on pharmacologic and surgical treatment.

Conclusion

A literature search allowed the development of evidence-based guidelines on the screening, diagnosis, treatment, and follow-up of MASLD in individuals with overweight or obesity.

Metabolic dysfunction-associated steatotic liver disease increases the risk of incident cardiovascular disease: a nationwide cohort study

Background

The various subcategories under the overarching term of steatotic liver disease (SLD) have been recently proposed by the nomenclature consensus group and endorsed by international academic liver societies. Our aim was to investigate the association between each subtype of SLD and incident cardiovascular disease (CVD) in a nationwide Korean cohort.

Methods

From a nationwide health screening database from Korea, 351,068 individuals aged 47-86 years between January 1, 2009 and December 31, 2010 were included and followed until December 31, 2019 for a median of 9.0 years. Individuals were categorised into no SLD, metabolic dysfunction-associated steatotic liver disease (MASLD), MASLD with increased alcohol intake (MetALD), and alcohol-related liver disease (ALD). Hepatic steatosis was defined as fatty liver index ≥60. The primary outcome was a composite CVD, which includes non-fatal and fatal myocardial infarction and stroke. The subdistribution hazard ratio (SHR) was calculated using the Fine-Gray model with treating non-CVD-related death as a competing risk.

Findings

There were 199,817 male (56.9%) and 151,251 female (43.1%) with a median age of 55 years (interquartile range, 50-61). The prevalence of no SLD, MASLD, MetALD, and ALD was 44.3%, 47.2%, 6.4%, and 2.1%, respectively; and the incidence rate of CVD in each subcategory was 6.2, 8.5, 8.5, and 9.6 per 1000 person-years, respectively. MASLD (SHR, 1.19; 95% confidence interval [CI], 1.15-1.24), MetALD (SHR, 1.28; 95% CI, 1.20-1.36), and ALD (SHR, 1.29; 95% CI, 1.18-1.41) increased the risk of CVD compared to no SLD, which increment was in consecutive order (Ptrend < 0.001).

Interpretation

Individuals with MASLD, MetALD, or ALD are at an increased risk of developing incident CVD. Higher risk of CVD observed in MetALD compared to MASLD suggests the additive impact of alcohol consumption in conjunction with cardiometabolic risk factors on CVD development. These findings support and validate the utility of the new consensus criteria for SLD in predicting CVD.

Funding

The National Research Foundation of Korea and the Korea Centers for Disease Control and Prevention.

Critical appraisal of metabolic dysfunction-associated steatotic liver disease: Implication of Janus-faced modernity

The existing term non-alcoholic fatty liver disease (NAFLD) has raised substantial concerns due to its inherent disadvantages of using exclusionary diagnostic criteria and the stigmatizing word 'fatty.' Three pan-national liver associations set out to explore a new nomenclature to replace both NAFLD and its suggested alternative, metabolic (dysfunction)-associated fatty liver disease (MAFLD). They surveyed if a change in nomenclature and/or definition is favored and which nomenclature best communicates disease characteristics and increases awareness. In lieu of NAFLD/MAFLD, metabolic dysfunction-associated steatotic liver disease (MASLD) has been chosen, and an umbrella term, steatotic liver disease (SLD), encompassing the whole spectrum of liver disease, has been proposed. It has been suggested that cardiometabolic risk factors should be considered when categorizing SLD patients. Furthermore, a new subcategory, MASLD with increased alcohol intake (MetALD), casts light on a neglected group of patients with moderate or more alcohol consumption. The importance of metabolic dysfunction was acknowledged in this new nomenclature, but the precise contribution of metabolic dysfunction and alcohol consumption to the development and progression of SLD remains unclear. Herein, we review hepatologists' and endocrinologists' perspectives on the new nomenclature, along with its possible impact on clinical practice. Although it is premature to predict the settlement of the new nomenclature, this review may help build more evidence for a soft landing of it in the future.

Corrected and republished from: Metabolic associated liver disease

Alcohol consumption (AC) and metabolic syndrome (MS) represent the first cause of liver disease, hepatocellular carcinoma and liver transplantation. The habit of consuming alcoholic beverages and the presence of MS and non-alcoholic fatty liver disease (NAFLD) often coexist in the same patient. The histoclinical boundaries between alcohol related liver disease (ALD) and NAFLD are often not well defined. The co-presence of AC and MS increases the risk of hepatic and extra-hepatic disease. The terminological evolution from NAFLD to metabolic associated fatty liver disease (MAFLD) is certainly a useful advance. However, it is known that the appearance of liver fibrosis increases oncologic and cardiovascular disease risk, which in the case of cirrhosis can be present even in the absence of steatosis and that the mechanisms of fibrogenesis can act independently of the presence of steatosis/steatohepatitis. For this reason, as already stated recently, a further terminological evolution can be hypothesized. This article was originally published with mistakes in the text. The new corrected citable version appears below.

An international multidisciplinary consensus statement on MAFLD and the risk of CVD

BACKGROUND

Fatty liver disease in the absence of excessive alcohol consumption is an increasingly common condition with a global prevalence of ~ 25-30% and is also associated with cardiovascular disease (CVD). Since systemic metabolic dysfunction underlies its pathogenesis, the term metabolic (dysfunction)-associated fatty liver disease (MAFLD) has been proposed for this condition. MAFLD is closely intertwined with obesity, type 2 diabetes mellitus and atherogenic dyslipidemia, which are established cardiovascular risk factors. Unlike CVD, which has received attention in the literature on fatty liver disease, the CVD risk associated with MAFLD is often underestimated, especially among Cardiologists.

METHODS AND RESULTS

A multidisciplinary panel of fifty-two international experts comprising Hepatologists, Endocrinologists, Diabetologists, Cardiologists and Family Physicians from six continents (Asia, Europe, North America, South America, Africa and Oceania) participated in a formal Delphi survey and developed consensus statements on the association between MAFLD and the risk of CVD. Statements were developed on different aspects of CVD risk, ranging from epidemiology to mechanisms, screening, and management.

CONCULSIONS

The expert panel identified important clinical associations between MAFLD and the risk of CVD that could serve to increase awareness of the adverse metabolic and cardiovascular outcomes of MAFLD. Finally, the expert panel also suggests potential areas for future research.

The bidirectional impacts of alcohol consumption and MAFLD for progressive fatty liver disease

Nonalcoholic fatty liver disease (NAFLD), once considered a benign condition, has been associated with several cardiometabolic complications over the past two decades. The worldwide prevalence of NAFLD is as high as 30%. NAFLD requires the absence of a "significant alcohol intake." Conflicting reports have suggested that moderate alcohol consumption may be protective; therefore, the diagnosis of NAFLD previously relied on negative criteria. However, there has been a significant increase in alcohol consumption globally. Apart from the rise in alcohol-related liver disease (ARLD), alcohol, a major toxin, is associated with an increased risk of several cancers, including hepatocellular carcinoma. Alcohol misuse is a significant contributor to disability-adjusted life years. Recently, the term metabolic dysfunction-associated fatty liver disease (MAFLD) was proposed instead of NAFLD to include the metabolic dysfunction responsible for the major adverse outcomes in patients with fatty liver disease. MAFLD, dependent on the "positive diagnostic criteria" rather than previous exclusion criteria, may identify individuals with poor metabolic health and aid in managing patients at increased risk of all-cause and cardiovascular mortality. Although MAFLD is less stigmatizing than NAFLD, excluding alcohol intake may increase the risk of already existing underreported alcohol consumption in this subgroup of patients. Therefore, alcohol consumption may increase the prevalence of fatty liver disease and its associated complications in patients with MAFLD. This review discusses the effects of alcohol intake and MAFLD on fatty liver disease.

NAFLD, MAFLD, and beyond: one or several acronyms for better comprehension and patient care

The term non-alcoholic fatty liver disease (NAFLD) has rapidly become the most common type of chronic liver disease. NAFLD points to excessive hepatic fat storage and no evidence of secondary hepatic fat accumulation in patients with "no or little alcohol consumption". Both the etiology and pathogenesis of NAFLD are largely unknown, and a definitive therapy is lacking. Since NAFLD is very often and closely associated with metabolic dysfunctions, a consensus process is ongoing to shift the acronym NAFLD to MAFLD, i.e., metabolic-associated fatty liver disease. The change in terminology is likely to improve the classification of affected individuals, the disease awareness, the comprehension of the terminology and pathophysiological aspects involved, and the choice of more personalized therapeutic approaches while avoiding the intrinsic stigmatization due to the term "non-alcoholic". Even more recently, other sub-classifications have been proposed to concentrate the heterogeneous causes of fatty liver disease under one umbrella. While awaiting additional validation studies in this field, we discuss the main reasons underlying this important shift of paradigm.

Meta-analysis: The impact of light-to-moderate alcohol consumption on progressive non-alcoholic fatty liver disease

BACKGROUND AND AIMS

Non-alcoholic fatty liver disease (NAFLD) is defined as fatty liver disease in the absence of heavy alcohol consumption. However, the impact of light-to-moderate alcohol consumption on progressive NAFLD and on mortality is presently unclear.

METHODS

Medline, Embase, OATD and OpenGrey were systematically searched up to November 2022 for relevant cross-sectional, case-control and cohort studies. The study outcomes were progressive NAFLD-steatohepatitis (NASH), fibrosis, cirrhosis, hepatocellular carcinoma (HCC) and mortality. The entire review process was performed by two independent reviewers. A narrative synthesis was performed for all outcomes, while meta-analyses, subgroup analyses and publication bias assessment were performed depending on the number of articles.

RESULTS

After study selection, 32 articles were included. Cohort studies reported that moderate alcohol intake increased the risk for advanced fibrosis (pooled OR 1.56; 95% CI 1.08-2.26 and HR 1.39; 95% CI 1.22-1.57), which was not observed in cross-sectional studies. Alcohol use also increased the risk of developing liver cirrhosis and HCC, but seemed to lower the risk of steatohepatitis. Light alcohol consumption protected against all-cause mortality, an effect not observed in NAFLD patients with moderate intake.

CONCLUSIONS

There is wide heterogeneity in studies on the impact of alcohol on progressive NAFLD. Nevertheless, cohort studies reported a significant harmful effect of moderate alcohol consumption on the occurrence of advanced fibrosis. Further research is needed to make valid recommendations with regard to alcohol consumption in patients with NAFLD.

The effects of moderate alcohol consumption on non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is accepted as a counterpart to alcohol-related liver disease because it is defined as hepatic steatosis without excessive use of alcohol. However, the definition of moderate alcohol consumption, as well as whether moderate alcohol consumption is beneficial or detrimental, remains controversial. In this review, the findings of clinical studies to date with high-quality evidence regarding the effects of moderate alcohol consumption in NAFLD patients were compared and summarized.

Stéatose hépatique non alcoolique : diagnostic et traitement en 2022

La NAFLD (Non Alcoholic Fatty Liver Disease ) est la manifestation hépatique d’un trouble métabolique multisystémique. Elle est la principale cause de maladie hépatique au niveau mondial, avec une prévalence croissante. Bien qu’il s’agisse principalement d’une maladie silencieuse à évolution lente, certains patients présentent un risque élevé de progression de la maladie et d’issues plus graves telles que la cirrhose, le carcinome hépatocellulaire et la transplantation hépatique. Malgré les multiples études menées et les nombreux essais cliniques en cours, il n’existe pas de médicaments approuvés pour la NAFLD/NASH (Non Alcoholic Steato-Hepatitis ), et le traitement doit donc se fonder sur des stratégies de modification du mode de vie. Cette revue explorera la définition et l’épidémiologie courantes de la NAFLD et de la NASH ainsi que les facteurs de risque et les conséquences de la maladie, tout en résumant les recommandations existantes pour le diagnostic, la stratification du risque et la prise en charge de la maladie.

NAFLD-related hepatocellular carcinoma: The growing challenge

Hepatocellular carcinoma (HCC) is a common cause of cancer-related mortality and morbidity worldwide. With the obesity pandemic, NAFLD-related HCC is contributing to the burden of disease exponentially. Genetic predisposition and clinical risk factors for NAFLD-related HCC have been identified. Cirrhosis is a well-known and major risk factor for NAFLD-related HCC. However, the occurrence of NAFLD-related HCC in patients without cirrhosis is increasingly recognized and poses a significant challenge regarding cancer surveillance. It is of paramount importance to develop optimal risk stratification scores and models to identify subsets of the population at high risk so they can be enrolled in surveillance programs. In this review, we will discuss the risks and prediction models for NAFLD-related HCC.

Machine learning-derived gut microbiome signature predicts fatty liver disease in the presence of insulin resistance

A simple predictive biomarker for fatty liver disease is required for individuals with insulin resistance. Here, we developed a supervised machine learning-based classifier for fatty liver disease using fecal 16S rDNA sequencing data. Based on the Kangbuk Samsung Hospital cohort (n = 777), we generated a random forest classifier to predict fatty liver diseases in individuals with or without insulin resistance (n = 166 and n = 611, respectively). The model performance was evaluated based on metrics, including accuracy, area under receiver operating curve (AUROC), kappa, and F1-score. The developed classifier for fatty liver diseases performed better in individuals with insulin resistance (AUROC = 0.77). We further optimized the classifiers using genetic algorithm. The improved classifier for insulin resistance, consisting of ten microbial genera, presented an advanced classification (AUROC = 0.93), whereas the improved classifier for insulin-sensitive individuals failed to distinguish participants with fatty liver diseases from the healthy. The classifier for individuals with insulin resistance was comparable or superior to previous methods predicting fatty liver diseases (accuracy = 0.83, kappa = 0.50, F1-score = 0.89), such as the fatty liver index. We identified the ten genera as a core set from the human gut microbiome, which could be a diagnostic biomarker of fatty liver diseases for insulin resistant individuals. Collectively, these findings indicate that the machine learning classifier for fatty liver diseases in the presence of insulin resistance is comparable or superior to commonly used methods.

Metabolic associated liver disease

In real practice the patient with liver disease is often the carrier of multiple etiological factors such as metabolic syndrome (MS) and alcohol consumption (AC). Their copresence is often underestimated and AC is not adequately studied. Traditionally to diagnose non-alcoholic fatty liver disease (NAFLD), AC must not exceed 30 gr for men and 20 gr for women per day. This limit should still be reduced, especially in relation to the AC and fibrogenesis ratio and also frequent misestimation of AC or unrecognized MS may underestimate multi caused liver injury. AC is a contributing cause of MS and alcoholic and non-alcoholic liver disease have a substantially overlapping histopathological picture. Moreover, AC and MS are cause and contributing cause of extra-hepatic morbidity and mortality. It can be concluded that the possible simplification of terminology at metabolic associated liver disease (MALD) makes clinical activity more usable and immediate, facilitates better communication and cooperation between scientific societies and specialists who apparently deal with different medical sectors, facilitates early identification of related hepatic and extra-hepatic pathology, allows to "see the person in a unitary way," to create more streamlined care pathways, to reduce the hospitalization rate with relative cost-benefit advantage and to create unitary prevention and health promotion policies.

Racial Disparities in Associations of Alcohol Consumption With Liver Disease Mortality in a Predominantly Low-Income Population: A Report From the Southern Community Cohort Study

Consistent with previous cross-sectional studies, in the Southern Community Cohort Study, the largest cohort for Black Americans conducted in a predominantly low-income population with 81,694 participants, we found that moderate alcohol drinking was associated with a significantly increased risk of mortality due to liver disease in Black Americans (hazard ratio = 2.06; 95% confidence interval: 1.08-3.94) but not in White Americans (hazard ratio = 0.87; 95% confidence interval: 0.52-1.44). We found that heavy drinking was significantly associated with an increased risk of mortality due to liver disease in both Black and White Americans. Future studies are warranted to understand the mechanism involving such racial disparity.

Epidemic characteristics of alcohol-related liver disease in Asia from 2000 to 2020: A systematic review and meta-analysis

BACKGROUND AND AIMS

To systematically summarize the prevalence of alcohol-related liver disease (ALD) and the alcohol-attributable proportions of liver cirrhosis and hepatocellular carcinoma (HCC) cases in Asia.

METHODS

The Embase, PubMed, Web of Science, Cochrane, CINAHL, WanfangMed and China National Knowledge Infrastructure databases were searched from 01 January 2000 to 01 December 2021 for reports of ALD prevalence and alcohol-attributable proportions of liver cirrhosis/HCC in Asian populations. Study characteristics were extracted, and meta-analyses were conducted.

RESULTS

Our literature search identified 13 studies reporting the ALD prevalence, 62 studies reporting the alcohol-attributable proportion of liver cirrhosis and 34 studies reporting the alcohol-attributable proportion of HCC. The overall prevalence of ALD was 4.81% (95% confidence interval [CI] 3.67%, 6.09%). The ALD prevalence was higher in men (7.80% [95% CI 5.70%, 10.19%]) than in women (0.88% [95% CI 0.35%, 1.64%]) and increased significantly over time from 3.82% (95% CI 2.74%, 5.07%) between 2000 and 2010 to 6.62% (95% CI 4.97%, 8.50%) between 2011 and 2020. Among 469 640 cases of liver cirrhosis, the pooled alcohol-attributable proportion was 12.57% (95% CI 10.20%, 15.16%). Among 82 615 HCC cases, the pooled alcohol-attributable proportion was 8.30% (95% CI 6.10%,11.21%). Significant regional differences were observed in alcohol-attributable proportions of liver cirrhosis and HCC.

CONCLUSIONS

The prevalence of ALD and the proportions of alcohol-related liver cirrhosis and HCC in Asia are lower than those in western populations. However, a gradual increasing trend was observed over the last 21 years. ALD is likely to emerge as a leading cause of chronic liver disease in Asia.

Risk for hepatic and extra-hepatic outcomes in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is defined by presence of steatosis in more than 5% of liver cells. The gold standard for diagnosis is liver biopsy, but this is seldom achieved due to costs and risk for side effects, and that is why the diagnosis is mostly made based on a combination of radiology and exclusion of other liver diseases. Disease severity staging can be noninvasively achieved with radiological exams such as elastography or blood-based markers that usually have lower sensitivity and specificity. NAFLD is today the most common chronic liver disease globally with a prevalence estimated to be 25%. Fortunately, for many persons NAFLD is an incidental finding with a good prognosis. Whilst a major focus has been on liver-related outcomes in NAFLD, there has recently been an increased interest in extrahepatic consequences of NAFLD. The most commonly studied outcomes include cardiovascular disease and cancer. The risk of adverse outcomes generally differs according to the baseline fibrosis stage. There is a five-time higher risk of liver-related events in NAFLD patients with fibrosis stage 3 as compared to those with no or little fibrosis. Meanwhile, the presence of nonalcoholic steatohepatitis (NASH) does not seem to influence prognosis in addition to fibrosis stage. Patients with NAFLD clearly have a higher risk for cardiovascular outcomes compared to the general population, with a recent meta-analysis indicating a 37% increased hazard for cardiovascular events as opposed to individuals without NAFLD. The risk of liver cancer is increased, which is mostly driven by presence of cirrhosis, but the increased risk is present also in patients without cirrhosis, and to a greater extent than for other chronic liver disease. Around one-third of patients with NAFLD and liver cancer do not have cirrhosis. Additionally, the risk of extrahepatic malignancies is thought to be moderately increased, with most evidence for a link between NAFLD and colorectal cancer where the risk is approximately 50% higher compared to patients without NAFLD. A particularly salient point is if NAFLD can be considered an independent risk factor for outcomes. Many studies have not been able to adjust for key confounders, or suffer from different forms of bias. The clinical problem is nevertheless to identify persons with an increased risk for adverse hepatic and extrahepatic outcomes. We here discuss the evidence linking NAFLD to severe hepatic and extrahepatic outcomes.

Association of the Metabolic Dysfunction-Associated Fatty Liver Disease with Serum Uric Acid-to-Creatinine Ratio

Background: No study has examined whether serum uric acid/creatinine (sUA/Cr) is associated with the newly defined metabolic-associated fatty liver disease (MAFLDs). Furthermore, studies on other factors influencing their relationship have not been conducted. Aim: To investigate the relationship between sUA/Cr and newly defined MAFLD, and to identify any factors that affect this relationship. Methods: We retrospectively reviewed the data of patients who underwent abdominal computed tomography (CT) at the Hospital Health Promotion Center. Participants were divided into the healthy (no evidence of liver disease; n = 707), MAFLD+non-heavy drinking (steatosis diagnosed by CT and drinking <140 and 70 grams/week for men and women, respectively; n = 291), and MAFLD+heavy drinking (fatty liver diagnosed by CT and drinking >140 and 70 grams/week for men and women, respectively; n = 61) groups. The relationship between sUA/Cr and MAFLD among the three groups were compared using multivariate logistic regression. Results: After adjusting for age, it was observed that when the sUA/Cr ratio increased by 1, the risk of MAFLD increased by 1.205 times the risk in the normal group. After adjusting for age, an increase by 1 in the sUA/Cr ratio increased the probability of non-heavy drinking+MAFLD and heavy drinking+MAFLD by 1.302 and 1.556 times, respectively, compared with healthy individuals. For those who smoked, the probability of heavy drinking+MAFLD was 9.901 times higher compared with healthy individuals. Conclusion: The newly defined MAFLD is related to sUA/Cr. The amount of alcohol consumption and smoking influenced the association between sUA/Cr and MAFLD.

Non-alcoholic fatty liver disease in adults 2021: A clinical practice guideline of the Italian Association for the Study of the Liver (AISF), the Italian Society of Diabetology (SID) and the Italian Society of Obesity (SIO)

Nonalcoholic fatty liver disease (NAFLD) is a common and emerging liver disease in adults, paralleling the epidemic of obesity and diabetes and leading to worrisome events (hepatocellular carcinoma and end-stage liver disease). In the past years, mounting evidence added insights about epidemiology, natural history, diagnosis and lifestyle-based or drug treatment of NAFLD. In this rapidly evolving scenario, members of the Associazione Italiana per lo Studio del Fegato, the Società Italiana di Diabetologia and the Società Italiana dell'Obesità reviewed current knowledge on NAFLD. The quality of the published evidence is graded, and practical recommendations are made following the rules and the methodology suggested in Italy by the Centro Nazionale per l'Eccellenza delle cure and Istituto Superiore di Sanità. Whenever possible, recommendations are placed within the context the Italian Healthcare system, with reference to specific experience and local diagnostic and management resources.Level of evidence Level of evidence of recommendations for each PICO question were reported according to available evidence.

MAFLD: Renovation of clinical practice and disease awareness of fatty liver

Recently, international expert panels have proposed a new definition of fatty liver: metabolic dysfunction-associated fatty liver disease (MAFLD). MAFLD is not just a simple renaming of non-alcoholic fatty liver disease (NAFLD). The unique feature of MAFLD is the inclusion of metabolic dysfunctions, which are high-risk factors for events. In addition, MAFLD is independent of alcohol intake and the co-existing causes of liver disease. This new concept of MAFLD may have a widespread impact on patients, medical doctors, medical staff, and various stakeholders regarding fatty liver. Thus, MAFLD may renovate clinical practice and disease awareness of fatty liver. In this review, we introduce the definition of and rationale for MAFLD. We further describe representative cases showing how the diagnostic processes differ between MAFLD and NAFLD. We also summarize recent studies comparing MAFLD with NAFLD and discuss the impact of MAFLD on clinical trials, Japanese populations, and disease awareness.

NAFLD in normal weight individuals

Nonalcoholic fatty liver disease (NAFLD) can develop in lean individuals. Despite a better metabolic profile, the risk of disease progression to hepatic inflammation, fibrosis, and decompensated cirrhosis in the lean is similar to that in obesity-related NAFLD and lean individuals may experience more severe hepatic consequences and higher mortality relative to those with a higher body mass index (BMI). In the absence of early symptoms and abnormal laboratory findings, lean individuals are not likely to be screened for NAFLD or related comorbidities; however, given the progressive nature of the disease and the increased risk of morbidity and mortality, a clearer understanding of the natural history of NAFLD in lean individuals, as well as efforts to raise awareness of the potential health risks of NAFLD in lean individuals, are warranted. In this review, we summarize available data on NAFLD prevalence, clinical characteristics, outcomes, and mortality in lean individuals and discuss factors that may contribute to the development of NAFLD in this population, including links between dietary and genetic factors, menopausal status, and ethnicity. We also highlight the need for greater representation of lean individuals in NAFLD-related clinical trials, as well as more studies to better characterize lean NAFLD, develop improved screening algorithms, and determine specific treatment strategies based on underlying etiology.

Effects of Moderate Alcohol Consumption in Non-Alcoholic Fatty Liver Disease

Alcoholic liver disease (ALD) and non-alcoholic fatty liver disease (NAFLD) have emerged as leading causes of chronic liver diseases worldwide. ALD and NAFLD share several pathophysiological patterns as well as histological features, while clinically, they are distinguished by the amount of alcohol consumed daily. However, NAFLD coexists with moderate alcohol consumption in a growing proportion of the population. Here, we investigated the effects of moderate alcohol consumption on liver injury, lipid metabolism, and gut microbiota in 30 NAFLD-patients. We anonymously assessed drinking habits, applying the AUDIT- and CAGE-questionnaires and compared subgroups of abstainers vs. low to harmful alcohol consumers (AUDIT) and Cage 0-1 vs. Cage 2-4. Patients who did not drink any alcohol had lower levels of γGT, ALT, triglycerides, and total cholesterol. While the abundance of Bacteroidaceae, Bifidobacteriaceae, Streptococcaceae, and Ruminococcaceae was higher in the low to harmful alcohol drinking cohort, the abundance of Rikenellaceae was higher in the abstainers. Our study suggests that even moderate alcohol consumption has an impact on the liver and lipid metabolism, as well as on the composition of gut microbiota.

Non-alcoholic fatty liver disease in adults 2021: A clinical practice guideline of the Italian Association for the Study of the Liver (AISF), the Italian Society of Diabetology (SID) and the Italian Society of Obesity (SIO)

Nonalcoholic fatty liver disease (NAFLD) is a common and emerging liver disease in adults, paralleling the epidemic of obesity and diabetes, and leading to worrisome events (hepatocellular carcinoma and end-stage liver disease). In the last years, mounting evidence added insights about epidemiology, natural history, diagnosis and lifestyle-based or drug treatment of NAFLD. In this rapidly evolving scenario, members of the Associazione Italiana per lo Studio del Fegato (AISF), the Società Italiana di Diabetologia (SID) and the Società Italiana dell'Obesità (SIO) reviewed current knowledge on NAFLD. The quality of the published evidence is graded, and practical recommendations are made following the rules and the methodology suggested in Italy by the Centro Nazionale per l'Eccellenza delle cure (CNEC) and Istituto Superiore di Sanità (ISS). Whenever possible, recommendations are placed within the context the Italian Healthcare system, with reference to specific experience and local diagnostic and management resources. Level of evidence: Level of evidence of recommendations for each PICO question were reported according to available evidence.

Burden of liver disease progression in hospitalized patients with type 2 diabetes mellitus

BACKGROUND & AIMS

There are uncertainties regarding the burden of liver disease in patients with type 2 diabetes (T2D). Thus, we aimed to quantify the burden of liver disease, identify risk factors, and estimate attributable risks in patients with T2D.

METHODS

We measured adjusted hazard ratios of liver disease progression to hepatocellular carcinoma and/or decompensated cirrhosis in a 2010-2020 retrospective, bicentric, longitudinal, cohort of 52,066 hospitalized patients with T2D.

RESULTS

Mean age was 64±14 years and 58% were men. Alcohol use disorders accounted for 57% of liver-related complications and were associated with all liver-related risk factors. Non-metabolic liver-related risk factors accounted for 37% of the liver burden. T2D control was not associated with liver disease progression. The incidence (95% CI) of liver-related complications and of competing mortality were 3.9 (3.5-4.3) and 27.8 (26.7-28.9) per 1,000 person-years at risk, respectively. The cumulative incidence of liver disease progression exceeded the cumulative incidence of competing mortality only in the presence of well-identified risk factors of liver disease progression, including alcohol use. The incidence of hepatocellular carcinoma was 0.3 (95% CI 0.1-0.5) per 1,000 person-years in patients with obesity and it increased with age. The adjusted hazard ratios of liver disease progression were 55.7 (40.5-76.6), 3.5 (2.3-5.2), 8.9 (6.9-11.5), and 1.5 (1.1-2.1), for alcohol-related liver disease, alcohol use disorders without alcohol-related liver disease, non-metabolic liver-related risk factors, and obesity, respectively. The attributable fractions of alcohol use disorders, non-metabolic liver-related risk factors, and obesity to the liver burden were 55%, 14%, and 7%, respectively.

CONCLUSIONS

In this analysis of data from 2 hospital-based cohorts of patients with T2D, alcohol use disorders, rather than obesity, contributed to most of the liver burden. These results suggest that patients with T2D should be advised to drink minimal amounts of alcohol.

LAY SUMMARY

There is uncertainty on the burden of liver-related complications in patients with type 2 diabetes. We studied the risks of liver cancer and complications of liver disease in over 50,000 patients with type 2 diabetes. We found that alcohol was the main factor associated with complications of liver disease. This finding has major implications on the alcohol advice given to patients with type 2 diabetes.

Long-term prognosis of patients with alcohol-related liver disease or non-alcoholic fatty liver disease according to metabolic syndrome or alcohol use

BACKGROUND & AIMS

The boundary between non-alcoholic (NAFLD) and alcohol-related liver disease (ALD) is based on alcohol consumption. However, metabolic syndrome and alcohol use frequently co-exist. The aim of this study was to determine prognostic factors of long-term morbidity and mortality in patients with NAFLD or ALD.

METHODS

From 2003 to 2016, all consecutive NAFLD or ALD patients were prospectively included in this cohort study. We evaluated overall survival, specific cause of mortality and occurrence of any complication. The primary endpoint was analysed by the Kaplan Meier method, secondary endpoints were estimated by Gray test method or logistic regressions. Factors independently associated with overall mortality and morbidity were identified by a multivariate Cox model.

RESULTS

A total of 3365 patients (1667 with ALD and 1698 with NAFLD) were included. Median follow-up was 54 months (range: 30-86) and 563 subjects died. In the overall population, overall mortality was higher in patients with ALD (HR: 10.1 [7.57-13.3]), and with weekly alcohol consumption >7 units (HR:1.66 [1.41-1.96]). Liver-related mortality was higher in patients with ALD (HR: 11 [7.27-16.5]). In the NAFLD group, weekly alcohol consumption >1 unit was associated with higher overall mortality (HR: 1.9 [1.1-3.4]), and weekly alcohol consumption >7 units was associated with higher overall morbidity (OR: 1.89 [1.61-2.21]). In the ALD group, the presence of metabolic syndrome was associated with higher overall (HR:1.27 [1.02-1.57]), and liver (HR: 1.47 [1.1-1.96]) mortalities, and overall (OR: 1.46 [1.14-1.88]), liver (OR: 1.46 [1.14-1.88]) morbidities.

CONCLUSION

In fatty liver diseases, light alcohol consumption and metabolic syndrome are prognosis cofactors.

Modest alcohol intake and mortality in individuals with elevated alanine aminotransferase levels: a nationwide cohort study

BACKGROUND

Alanine aminotransferase (ALT) levels are widely used to screen liver disease, and many asymptomatic individuals show elevated ALT levels. As elevated ALT level indicates liver injury, even a small amount of alcohol intake may be harmful in subjects with elevated ALT levels, but there is limited evidence of the effect of light to moderate amount of alcohol intake in this subgroup.

METHODS

A cohort of 367,612 men and women without established liver diseases (including chronic viral hepatitis, alcohol-associated liver disease, cirrhosis, liver transplantation, or rare forms of liver disease) who underwent at least 1 health screening exam between 2009 and 2015 were assessed for liver-related and all-cause mortality. Elevated ALT levels were defined as ≥ 34 U/L for men and 25 U/L for women.

RESULTS

In participants with normal ALT levels, the fully-adjusted hazard ratios (95% CI) for liver-related mortality comparing light and moderate drinkers to non-drinkers were 0.73 (0.51-1.05), and 1.06 (0.73-1.52), respectively. In participants with elevated ALT levels, the corresponding hazard ratios were 1.57 (1.08-2.28), and 2.09 (CI 1.46-2.99), respectively (p value for alcohol intake by ALT interaction < 0.01). For all-cause mortality, the fully-adjusted hazard ratios comparing light and moderate drinkers to non-drinkers in participants with normal ALT levels were 0.72 (0.66-0.77), and 0.89 (0.82-0.97), respectively. In participants with elevated ALT levels, the corresponding hazard ratios were 0.93 (0.81-1.08), and 1.31 (1.14-1.50), respectively (p value for alcohol intake by ALT interaction < 0.01).

CONCLUSIONS

Small amounts of alcohol intake were associated with increased liver-related and all-cause mortality among individuals with elevated ALT levels. Subjects with elevated ALT levels should be advised complete abstinence from alcohol.

Does moderate alcohol consumption accelerate the progression of liver disease in NAFLD? A systematic review and narrative synthesis

OBJECTIVES

Liver disease is a leading cause of premature death, partly driven by the increasing incidence of non-alcohol-related fatty liver disease (NAFLD). Many people with a diagnosis of NAFLD drink moderate amounts of alcohol. There is limited guidance for clinicians looking to advise these patients on the effect this will have on their liver disease progression. This review synthesises the evidence on moderate alcohol consumption and its potential to predict liver disease progression in people with diagnosed NAFLD.

METHODS

A systematic review of longitudinal observational cohort studies was conducted. Databases (Medline, Embase, The Cochrane Library and ClinicalTrials.gov) were searched up to September 2020. Studies were included that reported progression of liver disease in adults with NAFLD, looking at moderate levels of alcohol consumption as the exposure of interest. Risk of bias was assessed using the Quality in Prognostic factor Studies tool.

RESULTS

Of 4578 unique citations, 6 met the inclusion criteria. Pooling of data was not possible due to heterogeneity and studies were analysed using narrative synthesis. Evidence suggested that any level of alcohol consumption is associated with worsening of liver outcomes in NAFLD, even for drinking within recommended limits. Well conducted population based studies estimated up to a doubling of incident liver disease outcomes in patients with NAFLD drinking at moderate levels.

CONCLUSIONS

This review found that any level of alcohol intake in NAFLD may be harmful to liver health.Study heterogeneity in definitions of alcohol exposure as well as in outcomes limited quantitative pooling of results. Use of standardised definitions for exposure and outcomes would support future meta-analysis.Based on this synthesis of the most up to date longitudinal evidence, clinicians seeing patients with NAFLD should currently advise abstinence from alcohol.

PROSPERO REGISTRATION NUMBER

The protocol was registered with PROSPERO (#CRD42020168022).

Non-alcoholic fatty liver disease in adults 2021: A clinical practice guideline of the Italian Association for the Study of the Liver (AISF), the Italian Society of Diabetology (SID) and the Italian Society of Obesity (SIO)

Nonalcoholic fatty liver disease (NAFLD) is a common and emerging liver disease in adults, paralleling the epidemic of obesity and diabetes, and leading to worrisome events (hepatocellular carcinoma and end-stage liver disease). In the last years, mounting evidence added insights about epidemiology, natural history, diagnosis and lifestyle-based or drug treatment of NAFLD. In this rapidly evolving scenario, members of the Associazione Italiana per lo Studio del Fegato (AISF), the Società Italiana di Diabetologia (SID) and the Società Italiana dell'Obesità (SIO) reviewed current knowledge on NAFLD. The quality of the published evidence is graded, and practical recommendations are made following the rules and the methodology suggested in Italy by the Centro Nazionale per l'Eccellenza delle cure (CNEC) and Istituto Superiore di Sanità (ISS). Whenever possible, recommendations are placed within the context the Italian Healthcare system, with reference to specific experience and local diagnostic and management resources. Level of evidence: Level of evidence of recommendations for each PICO question were reported according to available evidence.

The egyptian clinical practice guidelines for the diagnosis and management of metabolic associated fatty liver disease

The landscape of chronic liver disease in Egypt has drastically changed over the past few decades. The prevalence of metabolic-associated fatty liver disease (MAFLD) has risen to alarming levels. Despite the magnitude of the problem, no regional guidelines have been developed to tackle this disease. This document provides the clinical practice guidelines of the key Egyptian opinion leaders on MAFLD screening, diagnosis, and management, and covers various aspects in the management of MAFLD. The document considers our local situations and the burden of clinical management for the healthcare sector and is proposed for daily clinical practical use. Particular reference to special groups was done whenever necessary.

Clinical practice advice on lifestyle modification in the management of nonalcoholic fatty liver disease in Japan: an expert review

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver diseases worldwide, including in Japan. The Japanese Society of Gastroenterology (JSGE) and the Japanese Society of Hepatology (JSH) have established the Japanese NAFLD/NASH guidelines in 2014 and revised these guidelines in 2020. As described in these guidelines, weight reduction by diet and/or exercise therapy is important for the treatment of NAFLD patients. The I148M single nucleotide polymorphism (rs738409 C > G) of PNPLA3 (patatin-like phospholipase domain-containing 3 protein) is widely known to be associated with the occurrence and progression of NAFLD. In the Japanese, the ratio of PNPLA3 gene polymorphisms found is approximately 20%, which is higher than that found in Westerners. In addition, the ratio of lean NAFLD patients is also higher in Japan than in Western countries. Therefore, the method for lifestyle guidance for the NAFLD patients in Japan would be different from that for the people in Western countries. The problems in the treatment of NAFLD patients include alcohol consumption and sarcopenia. Therefore, guidelines that can help clinicians treat Japanese patients with NAFLD are needed. In this expert review, we summarize evidence-based interventions for lifestyle modification (diet, exercise, alcohol, and sarcopenia) for the treatment of patients with NAFLD, especially from Japan and Asian countries.

Alcohol and Metabolic-associated Fatty Liver Disease

The diagnosis of metabolic-associated fatty liver disease is based on the detection of liver steatosis together with the presence of metabolic dysfunction. According to this new definition, the diagnosis of metabolic-associated fatty liver disease is independent of the amount of alcohol consumed. Actually, alcohol and its metabolites have various effects on metabolic-associated abnormalities during the process of alcohol metabolism. Studies have shown improved metabolic function in light to moderate alcohol drinkers. There are several studies focusing on the role of light to moderate alcohol intake on metabolic dysfunction. However, the results from studies are diverse, and the conclusions are often controversial. This review systematically discusses the effects of alcohol consumption, focusing on light to moderate alcohol consumption, obesity, lipid and glucose metabolism, and blood pressure.

Associations Between Alcohol Use and Liver-Related Outcomes in a Large National Cohort of Patients With Cirrhosis

Alcohol use can cause hepatic necroinflammation and worsening portal hypertension in patients with cirrhosis. We aimed to evaluate the associations between degree of alcohol use and clinical liver‐related outcomes according to etiology of cirrhosis. In this retrospective cohort analysis, 44,349 U.S. veterans with cirrhosis from alcohol‐associated liver disease (ALD), chronic hepatitis C virus (HCV) infection, or nonalcoholic fatty liver disease were identified who completed the Alcohol Use Disorders Identification Test Consumption questionnaire in 2012. Based on this score, level of alcohol use was categorized as none, low level, or unhealthy. Multivariable Cox proportional hazards regression was used to assess for associations between alcohol use and mortality, cirrhosis decompensation (new ascites, encephalopathy, or variceal bleeding), and hepatocellular carcinoma (HCC). At baseline, 36.4% of patients endorsed alcohol use and 17.1% had unhealthy alcohol use. During a mean 4.9 years of follow‐up, 25,806 (57.9%) patients died, 9,409 (21.4%) developed a new decompensation, and 4,733 (11.1%) developed HCC. In patients with ALD‐cirrhosis and HCV‐cirrhosis, unhealthy alcohol use, compared with no alcohol use, was associated with higher risks of mortality (adjusted hazard ratio [aHR] = 1.13, 95% confidence interval [CI] = 1.07‐1.19 and aHR = 1.14, 95% CI = 1.08‐1.20, respectively) and decompensation (aHR = 1.18, 95% CI = 1.07‐1.30 and aHR = 1.08, 95% CI = 1.00‐1.16, respectively). Alcohol use was not associated with HCC, regardless of cirrhosis etiology. Conclusion: Unhealthy alcohol use was common in patients with cirrhosis and was associated with higher risks of mortality and cirrhosis decompensation in patients with HCV‐cirrhosis and ALD‐cirrhosis. Therefore, health care providers should make every effort to help patients achieve abstinence. The lack of association between alcohol use and HCC merits further investigation.