Effect of lifetime alcohol consumption on the histological severity of non-alcoholic fatty liver disease

Impact of Longitudinal Alcohol Use Patterns on Long-Term Risk of Cirrhosis Among US Veterans With Steatotic Liver Disease

BACKGROUND & AIMS

Conflicting data exist on the impact of alcohol use on risk of liver disease progression in patients with steatotic liver disease. We aimed to evaluate the effect of longitudinal alcohol use on risk of cirrhosis among veterans with steatotic liver disease.

METHODS

US veterans with steatotic liver disease were identified from January 2010 through December 2022. Alcohol use was assessed using documented Alcohol Use Disorders Identification Test-Concise (AUDIT-C) scores and categorized as no alcohol (AUDIT-C = 0), low-risk alcohol use (AUDIT-C 1-2 for women and 1-3 for men), and high-risk alcohol (AUDIT-C ≥ 3 for women and ≥ 4 for men). Incidence of cirrhosis was evaluated with competing risks Nelson-Aalen methods. Adjusted multivariable regression models evaluated risks of cirrhosis associated with baseline alcohol use and changes in alcohol use during follow-up.

RESULTS

There were 1,156,189 veterans with steatotic liver disease identified (54.2% no alcohol, 34.6% low-risk alcohol, and 11.2% high-risk alcohol). Veterans with steatotic liver disease and high-risk alcohol have a 43% higher incidence of cirrhosis compared with patients reporting no alcohol use. Compared with patients with baseline high-risk alcohol who reported no change in alcohol use, those who decreased their alcohol use during follow-up experienced a 39% reduction in long-term risk of cirrhosis (hazard ratio, 0.61; 95% CI, 0.45-0.83; P < .01).

CONCLUSIONS

One in 9 veterans with steatotic liver disease report concurrent high-risk alcohol use, which is associated with 43% greater risk of cirrhosis compared with no alcohol use. However, reducing alcohol use lowers risk of cirrhosis, emphasizing the importance of timely alcohol use assessment and early interventions to address high-risk alcohol use in steatotic liver disease.

Response to semaglutide of non-drinker subjects with type 2 diabetes

BACKGROUND

Metabolic dysfunction-associated Steatotic Liver Disease (MASLD) displays a worse prognosis in subjects with type 2 diabetes (T2D); effective treatments are, so far, scanty. Semaglutide showed efficacy in improving steatohepatitis. We longitudinally observed a MASLD cohort of T2D subjects starting semaglutide, to detect an improvement of non-invasive surrogates of steatosis and fibro-inflammatory liver involvement, evaluating the role of mild alcohol consumption.

PATIENTS AND METHODS

In 62 overweight/obese T2D subjects with MASLD (36 non-drinker and 26 mild alcohol consumers), anthropometric, bio-humoral and transient elastography (TE) data were collected before (T0) and after an average time of 6.4 month (T1) from injective semaglutide prescription. Circulating levels of hormones (GIP, GLP-1, glucagon, insulin) and inflammatory markers (TNFα, MCP-1, IL-18, IL-10) were measured. Steatotic and necro-inflammatory liver involvement was evaluated with FibroScan controlled attenuation parameter (CAP) and liver stiffness (LS), respectively.

RESULTS

Significant (p < 0.006) T0-T1 reductions of BMI, waist circumference, fasting glucose, and HbA1c were observed. AST (-10 ± 3 IU/L), ALT (-18 ± 5 IU/L), GGT (-33 ± 15 IU/L), CAP (-25 ± 8 dB/m) and LS (-0.8 ± 0.4 kPa) were reduced, too. GLP-1 increased (+ 95.9 pM, p < 0.0001) and IL-18 was reduced (-46.6 pg/ml, p = 0.0002). After adjustment for confounders, CAP improving was only related to GLP-1 increase (ß=-0.437, p = 0.0122). Mild alcohol intake did not influence these relations.

CONCLUSION

Use of semaglutide in subjects with T2D and MASLD is associated with a significant decline of liver steatosis and necroinflammation proxies; mild alcohol assumption did not exert any influence. An independent effect of GLP-1 raise was observed on reduction of steatosis, irrespective of alcohol consumption.

Interactions between the metabolic syndrome and alcohol consumption increases the risk of liver disease

Alcohol-related liver disease (ALD) and non-alcoholic fatty liver disease (NAFLD, recently renamed metabolic dysfunction-associated steatotic liver disease [MASLD]) share many features, including certain pathophysiological mechanisms, susceptibility genes, and histological lesions. However, the natural history of the two diseases, studied separately, is significantly different, with ALD being associated with a higher risk of cirrhosis and liver-related mortality. Moreover, evidence suggests an interactive effect between ALD and metabolic risk factors that are associated with NAFLD on the risk of progressive fibrosis and development of cirrhosis. Patients with both a high consumption of alcohol and metabolic risk factors, such as obesity or diabetes, should therefore be considered a particularly high-risk group for cirrhosis. Additional studies regarding the efficacy of screening for advanced liver fibrosis or cirrhosis in these risk groups are needed. The most effective and established method for reducing the risk of progression in ALD is alcohol abstinence, whereas weight loss is effective in NAFLD. In this narrative review, we introduce the reader to the literature of the field and present key studies showing this interactive effect.

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.

Exclusive liquor and cocktail consumption is associated with at-risk fibrosis among nonheavy alcohol users with metabolic dysfunction-associated steatotic liver disease

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD) and alcohol consumption have both increased in recent years, and there is debate as to whether nonheavy alcohol use is safe in MASLD. We analyzed the association between different nonheavy alcohol use patterns and at-risk liver fibrosis among individuals with MASLD.

METHODS

We conducted a cross-sectional study of 1072 eligible National Health and Nutrition Examination Survey participants with MASLD who reported nonheavy alcohol consumption. We used vibration-controlled transient elastography to define the primary outcome of at-risk liver fibrosis as >8.2 kPa (stage F2-F4). Multivariable logistic regression models were used to determine the association of different alcohol consumption patterns (average drinks/day, drinking days/week, weekly alcohol intake, type of alcoholic beverage) and at-risk hepatic fibrosis, controlling for demographic/socioeconomic, lifestyle/dietary, and metabolic risk factors.

RESULTS

Exclusive liquor or cocktail drinkers had a 5.02-fold odds of at-risk fibrosis (95% CI: 1.15-21.95) compared with non-drinkers when controlling for potential confounders. While consuming an average of 2 drinks/day, ≥3 drinking days/week, or 1-3 drinks/week appeared to have a lower association with at-risk fibrosis when controlling for demographic/socioeconomic risk factors, the association was not present after controlling for lifestyle/dietary and metabolic risk factors.

CONCLUSIONS

There is an association between exclusive liquor/cocktail consumption and at-risk liver fibrosis in patients with MASLD who report nonheavy alcohol consumption.

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.

Advanced effect of curcumin and resveratrol on mitigating hepatic steatosis in metabolic associated fatty liver disease via the PI3K/AKT/mTOR and HIF-1/VEGF cascade

Metabolic associated fatty liver disease (MAFLD) is the most common chronic liver disease that has no viable treatment. Curcumin (Cur) and resveratrol (Res) are two natural products that have been studied for their potential to ameliorate MAFLD. However, while these compounds have been investigated individually, their combined use and the potential for a synergistic or augmented effect remain unexplored. This study aims to investigate the effect of curcumin (Cur) and resveratrol (Res) as a potential combination therapy on MAFLD. Cur, Res and Cur+Res were tested in palmitic acid (PA)-induced-HepG2 cells. MAFLD model was established using Goto-Kakizaki rats. The animals were treated with vehicle control (model group), Cur (150 mg/kg), Res (150 mg/kg), Cur+Res (150 mg/kg, 8:2, w/w), or metformin (Met, positive control, 400 mg/kg/day) via oral gavage for 4 weeks. Wistar rats were used as the control group. Network pharmacology was conducted to elucidate the molecular actions of Cur and Res, followed by q-PCR and immunoblotting in vivo. Cur+Res exhibited synergistic effects in reducing triglyceride, total cholesterol and lipid accumulation in PA-induced HepG2 cells. The combination also markedly attenuated hepatic steatosis in the MAFLD rats. Network pharmacology illustrated that the interaction of Cur and Res was associated with the modulation of multiple molecular targets associated with the PI3K/AKT/mTOR and HIF-1 signaling pathways. Experimental results confirmed that Cur+Res nomalised the gene targets and protein expressions in the PI3K/AKT/mTOR and HIF-1 signaling pathways, including PI3K, mTOR, STAT-3, HIF-1α, and VEGF. The present study demonstrated an advanced effect of Cur and Res in combination to attenuate MAFLD, and the mechanism is at least partly associated with the modulation of the PI3K/AKT/mTOR and HIF-1 signaling pathways.

Fatty Liver Disease, Metabolism and Alcohol Interplay: A Comprehensive Review

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide, and its incidence has been increasing in recent years because of the high prevalence of obesity and metabolic syndrome in the Western population. Alcohol-related liver disease (ArLD) is the most common cause of cirrhosis and constitutes the leading cause of cirrhosis-related deaths worldwide. Both NAFLD and ArLD constitute well-known causes of liver damage, with some similarities in their pathophysiology. For this reason, they can lead to the progression of liver disease, being responsible for a high proportion of liver-related events and liver-related deaths. Whether ArLD impacts the prognosis and progression of liver damage in patients with NAFLD is still a matter of debate. Nowadays, the synergistic deleterious effect of obesity and diabetes is clearly established in patients with ArLD and heavy alcohol consumption. However, it is still unknown whether low to moderate amounts of alcohol are good or bad for liver health. The measurement and identification of the possible synergistic deleterious effect of alcohol consumption in the assessment of patients with NAFLD is crucial for clinicians, since early intervention, advising abstinence and controlling cardiovascular risk factors would improve the prognosis of patients with both comorbidities. This article seeks to perform a comprehensive review of the pathophysiology of both disorders and measure the impact of alcohol consumption in patients with NAFLD.

Nutritional and Lifestyle Therapy for NAFLD in People with HIV

HIV infection and nonalcoholic fatty liver disease (NAFLD) are two major epidemics affecting millions of people worldwide. As people with HIV (PWH) age, there is an increased prevalence of metabolic comorbidities, along with unique HIV factors, such as HIV chronic inflammation and life-long exposure to antiretroviral therapy, which leads to a high prevalence of NAFLD. An unhealthy lifestyle, with a high dietary intake of refined carbohydrates, saturated fatty acids, fructose added beverages, and processed red meat, as well as physical inactivity, are known to trigger and promote the progression of NAFLD to nonalcoholic steatohepatitis, liver fibrosis, and hepatocellular carcinoma. Furthermore, with no currently approved pharmacotherapy and a lack of clinical trials that are inclusive of HIV, nutritional and lifestyle approaches still represent the most recommended treatments for PWH with NAFLD. While sharing common features with the general population, NAFLD in PWH displays its own peculiarities that may also reflect different impacts of nutrition and exercise on its onset and treatment. Therefore, in this narrative review, we aimed to explore the role of nutrients in the development of NAFLD in PWH. In addition, we discussed the nutritional and lifestyle approaches to managing NAFLD in the setting of HIV, with insights into the role of gut microbiota and lean NAFLD.

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.

Antibody to hepatitis B virus core antigen positivity is a predictor of non-alcoholic fatty liver disease severity

Insufficient information is available about co-factors favoring the progression of non-alcoholic fatty liver disease (NAFLD) toward cirrhosis. We aimed to evaluate the impact of a limited alcohol intake and of occult hepatitis B virus (HBV) infection (OBI) on the severity of NAFLD. Three-hundred-seventy-four alcohol non-abusers and HBV surface antigen negative NAFLD patients (223 males; mean age 55.4 years), consecutively admitted to the outpatients clinic of a referral liver unit from January 1st, 2018 to December 31st, 2019, were studied. Anti-HBV core antigen antibody [(anti-HBc), a surrogate marker of OBI] was assessed in all patients. Patients were distinguished between teetotal and moderate alcohol consumers (intake of less than 30 g and 20 g if males or females, respectively). Liver fibrosis was non-invasively assessed by FIB-4 and transient elastography. Uni- and multivariate analyses were performed to identify predictors of advanced fibrosis. Patients had a mean BMI of 28.5 kg/m², and the majority presented metabolic and cardio-vascular comorbidities [258 patients (69%) had insulin resistance/diabetes, 249 (66.6%) dyslipidemia, 200 (53.5%) arterial hypertension]. Multivariate analysis showed that anti-HBc positivity (p = 0.046, OR 2.153) was a factor associated with advanced fibrosis at FIB-4 score testing, whereas moderate alcohol intake was not associated with severe NAFLD both at FIB-4 and transient elastography evaluations. The study showed that a moderate alcohol intake has no impact on NAFLD severity and suggested that OBI might negatively affect the NAFLD outcome.

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.

Very Low Alcohol Consumption Is Associated with Lower Prevalence of Cirrhosis and Hepatocellular Carcinoma in Patients with Non-Alcoholic Fatty Liver Disease

The role of moderate alcohol consumption in the evolution of NAFLD is still debated. The aim of this study is to evaluate the impact of current and lifelong alcohol consumption in patients with NAFLD. From 2015 to 2020, we enrolled 276 consecutive patients fulfilling criteria of NAFLD (alcohol consumption up to 140 g/week for women and 210 g/week for men). According to their current alcohol intake per week, patients were divided in: abstainers, very low consumers (C1: <70 g/week) and moderate consumers (C2). We created a new tool, called LACU (Lifetime Alcohol Consuming Unit) to estimate the alcohol exposure across lifetime: 1 LACU was defined as 7 alcohol units per week for 1 drinking year. Patients were divided into lifelong abstainers and consumers and the latter furtherly divided into quartiles: Q1-Q4. Stratification according to alcohol intake, both current and cumulative as estimated by LACU, showed that very low consumers (C1 and Q1-Q3) displayed lower frequency of cirrhosis and hepatocellular carcinoma compared to abstainers and moderate consumers (C2 and Q4). We can speculate that up to one glass of wine daily in the context of a Mediterranean diet may be a long-term useful approach in selected NAFLD patients.

Association of metabolic dysfunction-associated fatty liver disease with kidney disease

Non-alcoholic fatty liver disease (NAFLD) is characterized by the accumulation of fat in more than 5% of hepatocytes in the absence of excessive alcohol consumption and other secondary causes of hepatic steatosis. In 2020, the more inclusive term metabolic (dysfunction)-associated fatty liver disease (MAFLD) - defined by broader diagnostic criteria - was proposed to replace the term NAFLD. The new terminology and revised definition better emphasize the pathogenic role of metabolic dysfunction and uses a set of definitive, inclusive criteria for diagnosis. Diagnosis of MAFLD is based on evidence of hepatic steatosis (as assessed by liver biopsy, imaging techniques or blood biomarkers and scores) in persons who are overweight or obese and have type 2 diabetes mellitus or metabolic dysregulation, regardless of the coexistence of other liver diseases or excessive alcohol consumption. The known association between NAFLD and chronic kidney disease (CKD) and our understanding that CKD can occur as a consequence of metabolic dysfunction suggests that individuals with MAFLD - who by definition have fatty liver and metabolic comorbidities - are at increased risk of CKD. In this Perspective article, we discuss the clinical associations between MAFLD and CKD, the pathophysiological mechanisms by which MAFLD may increase the risk of CKD and the potential drug treatments that may benefit both conditions.

Alcohol Consumption and Cardiovascular Outcomes in Patients With Nonalcoholic Fatty Liver Disease: A Population-Based Cohort Study

Low-level alcohol consumption is associated with reduced cardiovascular disease (CVD) in the general population. It is unclear whether this association is seen in patients with nonalcoholic fatty liver disease (NAFLD) who have an increased risk of CVD. We examined the association between alcohol consumption and CVD-related outcomes in subjects with NAFLD from a general population cohort. Subjects participating in the 1994-1995 Busselton Health survey underwent clinical and biochemical assessment. NAFLD was identified using the Fatty Liver Index of >60, and alcohol consumption quantified using a validated questionnaire. CVD hospitalizations and death during the ensuing 20 years were ascertained using the Western Australian data linkage system. A total of 659 of 4,843 patients were diagnosed with NAFLD. The average standard drinks per week was 8.0 for men and 4.0 for women. Men consuming 8-21 drinks per week had a 38% (hazard ratio [HR] 0.62, 95% confidence interval [CI] 0.43-0.90) lower risk of CVD hospitalization as compared with men consuming 1-7 drinks per week. With both men and women combined, consumption of 8-21 drinks per week was associated with a 32% (HR 0.68, 95% CI 0.49-0.93) reduction in CVD hospitalization in minimally adjusted and 29% (HR 0.71, 95% CI 0.51-0.99) in fully adjusted models. No protective association was observed with binge drinking. There was no association between alcohol consumption and CVD death. Conclusion: Low to moderate alcohol consumption is associated with fewer CVD hospitalizations but not CVD death in subjects with NAFLD.

Synergistic and Detrimental Effects of Alcohol Intake on Progression of Liver Steatosis

Nonalcoholic fatty liver disease (NAFLD) and alcoholic liver disease (ALD) are the most common liver disorders worldwide and the major causes of non-viral liver cirrhosis in the general population. In NAFLD, metabolic abnormalities, obesity, and metabolic syndrome are the driving factors for liver damage with no or minimal alcohol consumption. ALD refers to liver damage caused by excess alcohol intake in individuals drinking more than 5 to 10 daily units for years. Although NAFLD and ALD are nosologically considered two distinct entities, they show a continuum and exert synergistic effects on the progression toward liver cirrhosis. The current view is that low alcohol use might also increase the risk of advanced clinical liver disease in NAFLD, whereas metabolic factors increase the risk of cirrhosis among alcohol risk drinkers. Therefore, special interest is now addressed to individuals with metabolic abnormalities who consume small amounts of alcohol or who binge drink, for the role of light-to-moderate alcohol use in fibrosis progression and clinical severity of the liver disease. Evidence shows that in the presence of NAFLD, there is no liver-safe limit of alcohol intake. We discuss the epidemiological and clinical features of NAFLD/ALD, aspects of alcohol metabolism, and mechanisms of damage concerning steatosis, fibrosis, cumulative effects, and deleterious consequences which include hepatocellular carcinoma.

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).

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.

Diet and exercise in NAFLD/NASH: Beyond the obvious

Lifestyle represents the most relevant factor for non-alcoholic fatty liver disease (NAFLD) as the hepatic manifestation of the metabolic syndrome. Although a tremendous body of clinical and preclinical data on the effectiveness of dietary and lifestyle interventions exist, the complexity of this topic makes firm and evidence-based clinical recommendations for nutrition and exercise in NAFLD difficult. The aim of this review is to guide readers through the labyrinth of recent scientific findings on diet and exercise in NAFLD and non-alcoholic steatohepatitis (NASH), summarizing "obvious" findings in a holistic manner and simultaneously highlighting stimulating aspects of clinical and translational research "beyond the obvious". Specifically, the importance of calorie restriction regardless of dietary composition and evidence from low-carbohydrate diets to target the incidence and severity of NAFLD are discussed. The aspect of ketogenesis-potentially achieved via intermittent calorie restriction-seems to be a central aspect of these diets warranting further investigation. Interactions of diet and exercise with the gut microbiota and the individual genetic background need to be comprehensively understood in order to develop personalized dietary concepts and exercise strategies for patients with NAFLD/NASH.

The Effects of Modest Alcohol Consumption on Non-alcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis

Background and Objective: There is no consensus regarding modest alcohol consumption in patients with non-alcoholic fatty liver disease (NAFLD) due to conflicting results. The aim of this meta-analysis was to examine the effects of modest alcohol consumption on histological severity, histological course, hepatocellular carcinoma, and long-term clinical outcomes in NAFLD patients.

Methods: We searched MEDLINE and EMBASE databases from inception to October 2020 for studies evaluating the effects of modest alcohol consumption among patients with NAFLD. A random-effects meta-analysis using pooled odds ratio (OR) and hazard ratio (HR) was calculated with 95% confidence interval (CI). Study quality was assessed with the Newcastle-Ottawa Scale.

Results: Fourteen cross-sectional or cohort studies with aggregate data on 14,435 patients were included in the analysis. Modest alcohol consumption resulted in lower risks for steatohepatitis (OR 0.59; 95% CI 0.45–0.78; I² = 12%) and advanced fibrosis (OR 0.59, 95% CI 0.36–0.95; I² = 75%). Histological follow-up data showed that modest alcohol use was associated significantly with less steatohepatitis resolution but not with fibrosis progression. The HR for developing hepatocellular carcinoma was 3.77 (95% CI 1.75–8.15; I² = 0%). NAFLD patients with modest alcohol intake had a lower mortality risk than lifelong abstainers (HR 0.85; 95% CI 0.75–0.95; I² = 64%).

Conclusion: This meta-analysis suggests that medical advice for modest alcohol drinking should be made cautiously in caring for an individual patient based on the clinical context. Practically, patients with steatohepatitis or advanced fibrosis should avoid alcohol use, whereas patients with low fibrosis risk may be allowed for modest and safe drinking.

Alcohol consumption in patients with nonalcoholic fatty liver disease: yes, or no?

Excessive alcohol intake is an established risk factor for chronic liver disease. At the same time, moderate alcohol intake appears to reduce cardiovascular morbidity. Accordingly, recommendations for alcohol intake in patients with nonalcoholic fatty liver disease (NAFLD), who are at increased risk for liver-related and cardiovascular events, are a point of debate. Some studies have shown beneficial effects of alcohol on cardiovascular and overall mortality in this specific subset of patients. Nonetheless, even light alcohol intake appears to aggravate liver disease and increase the risk of hepatocellular cancer. Therefore, patients with nonalcoholic steatohepatitis or advanced fibrosis should be advised against consuming alcohol. On the other hand, only light alcohol consumption (<10 g/day) might be permitted in patients without significant hepatic fibrosis, provided that they are carefully followed-up. As the research field focusing on NAFLD keeps widening, more prospective studies regarding this specific subject are expected, and may provide a basis for less ambiguous recommendations.

Current management of NAFLD/NASH

NAFLD is the most common cause of liver disease worldwide, and its prevalence is significantly increasing. Studies have shown that it is associated with comorbidities such as diabetes, metabolic syndrome and obesity. Early diagnosis and management are highly important and could modify the prognosis of the disease. Evaluating the possibility of multiple aetiologies and recognizing the additional causes of liver disease should be a part of the patient's initial assessment. There are no approved drug treatments as yet, so the main management strategies should involve lifestyle changes such as physical activity and dietary re-education.

Joint associations of adiposity and alcohol consumption with liver disease-related morbidity and mortality risk: findings from the UK Biobank

BACKGROUND

The incidence of both non-alcoholic fatty liver disease (NAFLD) and alcoholic fatty liver disease (ALD) are expected to grow as a consequence of the ongoing obesity and alcohol consumption trends.

OBJECTIVE

We examined the joint associations of adiposity (body mass index (BMI) and waist circumference (WC)) and alcohol consumption on ALD, NAFLD and liver disease incidence and mortality (n = 465,437).

METHODS

Alcohol consumption was categorised based on current UK guidelines (14 units/week). Data were analysed using Cox proportional hazard models. A total of 1090 liver disease deaths, 230 ALD deaths and 192 NAFLD deaths occurred over an average follow-up length of 10.5 ± 1.7 years.

RESULTS

In multivariate models, we observed greater point estimates for risk of ALD, NAFLD and liver disease incidence and mortality among overweight/obese participants who consumed alcohol at the same level as normal weight participants. We found that overweight/obese participants who reported alcohol consumption above the guidelines had a greater HR for liver disease incidence and mortality (HR 1.52, 95% CI 1.32, 1.75 and HR 2.20, 95% CI 1.41, 3.44, respectively) than normal weight individuals (HR 0.95, 95% CI 0.83, 1.09 and HR 1.24, 95% CI 0.8, 1.93, respectively). The results for the associations of alcohol consumption and WC with ALD, NAFLD and liver disease mortality were similar. Participants with high WC who reported alcohol consumption above the guidelines had a greater HR for liver disease incidence (HR 1.59, 95% CI 1.35, 1.87) than normal WC individuals (HR 0.85, 95% CI 0.72, 1.01).

CONCLUSIONS

We found evidence that being overweight/obese amplified the harmful effect of alcohol on the liver incidence and mortality.

Modest alcohol consumption and risk of advanced liver fibrosis in nonalcoholic fatty liver disease: a systematic review and meta-analysis

Background

Recent studies have suggested an association between modest alcohol consumption and a decreased risk of advanced liver fibrosis among patients with nonalcoholic fatty liver disease (NAFLD) although the results are inconsistent. The current systematic review and meta-analysis was conducted to comprehensively investigate this possible association by identifying all the relevant studies and combining their results.

Methods

A comprehensive literature review was conducted utilizing the MEDLINE and EMBASE databases through February 2019 to identify all cross-sectional studies that compared the prevalence of advanced liver fibrosis among NAFLD patients who were modest alcohol drinkers to NAFLD patients who were non-drinkers. Effect estimates from each study were extracted and combined together using the random-effect, generic inverse variance method of DerSimonian and Laird.

Results

A total of 6 studies with 8,936 participants fulfilled the eligibility criteria and were included in the meta-analysis. The risk of advanced liver fibrosis among patients with NAFLD who were modest alcohol drinkers was significantly lower compared to patients with NAFLD who were non-drinkers with a pooled odds ratio of 0.51 (95% confidence interval [CI] 0.35-0.75; I² 47%). The funnel plot was symmetric and was not suggestive of publication bias.

Conclusion

A significantly lower risk of advanced liver fibrosis was observed among NAFLD patients who were modest alcohol drinkers compared to non-drinkers in this meta-analysis.

NAFLD and Cardiovascular Diseases: Epidemiological, Mechanistic and Therapeutic Considerations

Overwhelming evidence suggests an association of cardiovascular disease (CVD) with non-alcoholic fatty liver disease (NAFLD); however, the underlying mechanisms remain largely speculative. It is, however, likely that common mechanisms contribute to the development of CVD and NAFLD, with lifestyle factors such as smoking, sedentary lifestyle with poor nutrition habits and physical inactivity being major candidates. These behavioral factors, on a predisposing genetic background, trigger changes in gut microbiota, inflammation, dyslipidemia and oxidative stress, leading to metabolic syndrome, diabetes and obesity as well as atherosclerosis. Treatment options to counteract both the progression and development of CVD and NAFLD include lifestyle interventions, optimal medical therapy of comorbid conditions and, as final possibility, bariatric surgery. As no causal pharmacotherapy of NAFLD is available, further research is urgently needed to address the unmet need of a growing population with NAFLD and CVD.

Experimental models of metabolic and alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is a multi-systemic disease that is considered the hepatic manifestation of metabolic syndrome (MetS). Because alcohol consumption in NAFLD patients is common, there is a significant overlap in the pathogenesis of NAFLD and alcoholic liver disease (ALD). Indeed, MetS also significantly contributes to liver injury in ALD patients. This “syndrome of metabolic and alcoholic steatohepatitis” (SMASH) is thus expected to be a more prevalent presentation in liver patients, as the obesity epidemic continues. Several pre-clinical experimental models that couple alcohol consumption with NAFLD-inducing diet or genetic obesity have been developed to better understand the pathogenic mechanisms of SMASH. These models indicate that concomitant MetS and alcohol contribute to lipid dysregulation, oxidative stress, and the induction of innate immune response. There are significant limitations in the applicability of these models to human disease, such as the ability to induce advanced liver injury or replicate patterns in human food/alcohol consumption. Thus, there remains a need to develop models that accurately replicate patterns of obesogenic diet and alcohol consumption in SMASH patients.

MAFLD identifies patients with significant hepatic fibrosis better than NAFLD

BACKGROUND & AIMS

Diagnostic criteria for metabolic associated fatty liver disease (MAFLD) have been proposed, but not validated. We aimed to compare the diagnostic accuracy of the MAFLD definition vs the existing NAFLD criteria to identify patients with significant fibrosis and to characterize the impact of mild alcohol intake.

METHODS

We enrolled 765 Japanese patients with fatty liver (median age 54 years). MAFLD and NAFLD were diagnosed in 79.6% and 70.7% of patients respectively. Significant fibrosis was defined by FIB-4 index ≥1.3 and liver stiffness ≥6.6 kPa using shear wave elastography. Mild alcohol intake was defined as <20 g/day. Factors associated with significant fibrosis were analysed by logistic regression and decision-tree analyses.

RESULTS

Liver stiffness was higher in MAFLD compared to NAFLD (7.7 vs 6.8 kPa, P = .0010). In logistic regression, MAFLD (OR 4.401; 95% CI 2.144-10.629; P < .0001), alcohol intake (OR 1.761; 95% CI 1.081-2.853; P = .0234), and NAFLD (OR 1.721; 95%CI 1.009-2.951; P = .0463) were independently associated with significant fibrosis. By decision-tree analysis, MAFLD, but not NAFLD or alcohol consumption was the initial classifier for significant fibrosis. The sensitivity for detecting significant fibrosis was higher for MAFLD than NAFLD (93.9% vs 73.0%). In patients with MAFLD, even mild alcohol intake was associated with an increase in the prevalence of significant fibrosis (25.0% vs 15.5%; P = .0181).

CONCLUSIONS

The MAFLD definition better identifies a group with fatty liver and significant fibrosis evaluated by non-invasive tests. Moreover, in patients with MAFLD, even mild alcohol consumption is associated with worsening of hepatic fibrosis measures.

Unhealthy lifestyle habits and physical inactivity among Asian patients with non-alcoholic fatty liver disease

BACKGROUND & AIMS

Lifestyle modification is the cornerstone for the management of non-alcoholic fatty liver disease (NAFLD). We aim to understand lifestyle habits of NAFLD patients, compare across Asian regions and identify area of deficiency.

METHODS

In the multi-centre controlled attenuation parameter (CAP)-Asia study, we collected clinical data and lifestyle habit data of NAFLD patients from Singapore, mainland China, Hong Kong, Taiwan and Malaysia. Physical activity was assessed using the International Physical Activity Questionnaire.

RESULTS

A total of 555 patients were included in the final analysis (mean age 54.5 ± 11.2 years, 54.1% men and median liver stiffness 6.7 kPa). More patients from mainland China (27.4%) and Taipei (25.0%) were smokers. Modest drinking was more common in Taiwan (25.0%) and Hong Kong (18.2%); only 1.3% had binge drinking. Majority of patients drank coffee (64.0%) and tea (80.2%), with varying amounts and durations in different regions. Soft drinks consumption was most common in Singapore (62.2%) and Malaysia (57.7%). Only 29.7% of patients met the Physical Activity Guidelines Recommendations, with no major differences across regions. Patients with liver stiffness <10 kPa were more likely to report any vigorous activity, and sitting time was an independent factor associated with high CAP. Tea and coffee consumption were independently associated with high CAP and liver stiffness, respectively.

CONCLUSIONS

Despite some heterogeneity, unhealthy lifestyle and physical inactivity are common across Asian regions. Patients with liver stiffness <10 kPa were more likely to report any vigorous activity. Healthcare providers may use the comparative data to identify areas of deficiency.

Established and emerging factors affecting the progression of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease affecting approximately 25% of the global population. Although a majority of NAFLD patients will never experience liver-related symptoms it is estimated that 5-10% will develop cirrhosis-related complications with risk of death or need for liver transplantation. NAFLD is closely associated with cardiovascular disease and components of the metabolic syndrome. However, NAFLD is not uncommon in lean individuals and may in these subjects represent a different entity with separate pathophysiological mechanisms involved implying a higher risk for development of end-stage liver disease. There is considerable fluctuation in the histopathological course of NAFLD that may partly be attributed to lifestyle factors and dietary composition. Nutrients such as fructose, monounsaturated fatty acids, and trans-fatty acids may aggravate NAFLD. Presence of type 2 diabetes mellitus seems to be the most important clinical predictor of liver-related morbidity and mortality in NAFLD. Apart from severity of the metabolic syndrome, genetic polymorphisms and environmental factors, such as moderate alcohol consumption, may explain the variation in histopathological and clinical outcome among NAFLD patients.

Non-alcoholic Fatty Liver Disease and Alcohol-Related Liver Disease: Two Intertwined Entities

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide, with a prevalence of 25-30%. Since its first description in 1980, NAFLD has been conceived as a different entity from alcohol-related fatty liver disease (ALD), despite that, both diseases have an overlap in the pathophysiology, share genetic-epigenetic factors, and frequently coexist. Both entities are characterized by a broad spectrum of histological features ranging from isolated steatosis to steatohepatitis and cirrhosis. Distinction between NAFLD and ALD is based on the amount of consumed alcohol, which has been arbitrarily established. In this context, a proposal of positive criteria for NAFLD diagnosis not considering exclusion of alcohol consumption as a prerequisite criterion for diagnosis had emerged, recognizing the possibility of a dual etiology of fatty liver in some individuals. The impact of moderate alcohol use on the severity of NAFLD is ill-defined. Some studies suggest protective effects in moderate doses, but current evidence shows that there is no safe threshold for alcohol consumption for NAFLD. In fact, given the synergistic effect between alcohol consumption, obesity, and metabolic dysfunction, it is likely that alcohol use serves as a significant risk factor for the progression of liver disease in NAFLD and metabolic syndrome. This also affects the incidence of hepatocellular carcinoma. In this review, we summarize the overlapping pathophysiology of NAFLD and ALD, the current data on alcohol consumption in patients with NAFLD, and the effects of metabolic dysfunction and overweight in ALD.

Alcohol Use Is Associated With Hepatic Steatosis Among Persons With Presumed Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS

Many individuals presumed to have nonalcoholic fatty liver disease (NAFLD) consume moderate amounts of alcohol. Little is known about patterns of alcohol use in patients with NAFLD or how drinking behaviors affect liver fat.

METHODS

We conducted a cross-sectional study of 2475 participants of the Framingham Heart Study with hepatic steatosis, as determined by computed tomography. We performed multivariable-adjusted logistic regression models to evaluate the association between alcohol drinking patterns and hepatic steatosis. Models were adjusted for sociodemographic factors, diet, and the components of the metabolic syndrome. We excluded heavy alcohol users, defined as women who consume more than 14 alcohol drinks per week and men who consume more than 21 alcohol drinks per week.

RESULTS

In our sample (mean age, 49.8 ± 10.2 y; 50.3% women), the prevalence of hepatic steatosis was 17.5%. The total number of alcohol drinks per week and the maximum drinks consumed per drinking day each were associated with hepatic steatosis (adjusted odds ratio [aOR], 1.15; 95% CI, 1.02-1.29 and aOR 1.15; 95% CI, 1.02-1.30). Binge drinking occurred in 25.4% of individuals with presumed NAFLD and was associated with an increased odds of hepatic steatosis (aOR, 1.45; 95% CI, 1.06-1.98) among alcohol users. In a beverage-specific analysis, alcohol use patterns were associated with hepatic steatosis among beer drinkers, but not among wine drinkers.

CONCLUSIONS

In a cross-sectional study of participants of the Framingham Heart Study with hepatic steatosis, we observed an association between alcohol use and liver fat, even after excluding heavy alcohol users from our analysis. Alcohol use therefore appears to be a risk factor for NAFLD. Prospective studies are needed to validate these findings and determine if alcohol use should be a focus for research, prevention, and treatment of presumed NAFLD.

What's in a name? Renaming 'NAFLD' to 'MAFLD'

In medicine, language matters and the words used to name and describe a disease can have a profound impact on patients and their families. Over the last two decades, many criticisms have been voiced about the nomenclature and definition of non-alcoholic fatty liver disease (NAFLD) in regards not only to the prominent role that alcohol plays in the definition but also on the negative impacts of the nomenclature including trivialization, stigmatization and less consideration of the disease in health policy. Recently, a consensus of international experts proposed that the disease acronym be changed from NAFLD to metabolic (dysfunction) associated fatty liver disease or 'MAFLD'. This change goes far beyond a mere semantic revision and may be the first step that catalyses the process to better conceptualize the disease for health promotion, patient orientation, case identification, ongoing clinical trials and for health services delivery. Here we review the history of, and definitions of MAFLD in the context of advancing our understanding of the pathogenesis of the disease. We also address the reasons, signals, promises, challenges and the way going forward from the name change from various stakeholder perspectives.

MAFLD: A Consensus-Driven Proposed Nomenclature for Metabolic Associated Fatty Liver Disease

Fatty liver associated with metabolic dysfunction is common, affects a quarter of the population, and has no approved drug therapy. Although pharmacotherapies are in development, response rates appear modest. The heterogeneous pathogenesis of metabolic fatty liver diseases and inaccuracies in terminology and definitions necessitate a reappraisal of nomenclature to inform clinical trial design and drug development. A group of experts sought to integrate current understanding of patient heterogeneity captured under the acronym nonalcoholic fatty liver disease (NAFLD) and provide suggestions on terminology that more accurately reflects pathogenesis and can help in patient stratification for management. Experts reached consensus that NAFLD does not reflect current knowledge, and metabolic (dysfunction) associated fatty liver disease "MAFLD" was suggested as a more appropriate overarching term. This opens the door for efforts from the research community to update the nomenclature and subphenotype the disease to accelerate the translational path to new treatments.

Risks of Light and Moderate Alcohol Use in Fatty Liver Disease: Follow-Up of Population Cohorts

BACKGROUND AND AIMS

The effects of alcohol use in nonalcoholic fatty liver disease are unclear. We investigated the impact of alcohol use in fatty liver disease on incident liver, cardiovascular, and malignant disease, as well as death.

APPROACH AND RESULTS

Our study comprised 8,345 persons with hepatic steatosis (fatty liver index >60) who participated in health-examination surveys (FINRISK 1992-2012 or Health 2000), with available data on baseline alcohol intake. Main exclusions were baseline clinical liver disease, viral hepatitis, ethanol intake >50 g/day, and current abstainers. Data were linked with national registers for hospital admissions, malignancies, and death regarding liver, cardiovascular, and malignant disease, as well as all-cause death. Adjustment were for multiple confounders. Alcohol consumption showed a dose-dependent risk increase for incident advanced liver disease and malignancies. Consuming 10-19 g/day of alcohol in general or 0-9 g/day as nonwine beverages doubled the risk for advanced liver disease compared to lifetime abstainers. In contrast, alcohol intake up to 49 g/day was associated with a 22%-40% reduction of incident cardiovascular disease (CVD). We observed a J-shaped association between alcohol intake and all-cause death with a maximal risk reduction of 21% (95% confidence interval, 5%-34%) at alcohol intake of 0-9 g/day compared to lifetime abstainers. However, these benefits on CVD and mortality were only observed in never smokers. Alcohol intake >30 g/day yielded increased risk estimates for mortality compared to lifetime abstainers. In a subpopulation with longitudinal data, alcohol intake remained stable over time in >80% of subjects.

CONCLUSIONS

Even low alcohol intake in fatty liver disease is associated with increased risks for advanced liver disease and cancer. Low to moderate alcohol use is associated with reduced mortality and CVD risk but only among never smokers.

Effects of Moderate Alcohol Drinking in Patients with Nonalcoholic Fatty Liver Disease

Whether moderate alcohol intake is beneficial remains an unsolved issue. Recent studies have suggested that moderate alcohol consumption is associated with beneficial effects related to the prevention of cardiovascular diseases. Moderate alcohol consumption leads to a higher risk of hepatocellular carcinoma in patients with chronic viral liver diseases. However, the effects of moderate alcohol intake in patients with nonalcoholic fatty liver disease are unclear. In this review, we analyzed, from various perspectives, the effect of moderate alcohol consumption in patients with nonalcoholic fatty liver disease. We reviewed four cohort studies and seven cross-sectional studies. The results showed that moderate alcohol consumption was negatively related to the incidence of nonalcoholic steatohepatitis and liver fibrosis. However, moderate alcohol consumption was positively associated with the incidence of hepatocellular carcinoma in patients with nonalcoholic fatty liver disease. The results of the analysis of the relationship between moderate alcohol consumption and the levels of triglycerides, total cholesterol, high-density lipoprotein, and hypertension were diverse. More clinical data are needed to draw a conclusion about the effects of moderate alcohol consumption in patients with nonalcoholic fatty liver disease.

Moderate Alcohol Intake in Non-Alcoholic Fatty Liver Disease: To Drink or Not to Drink?

Nonalcoholic fatty liver disease (NAFLD) is defined by hepatic steatosis in the presence of alcohol intake within safe limits, defined by guidelines of scientific associations (usually 20 g or 2 units/day in women, 30 g or 3 units in men). The diagnosis is usually followed by medical counseling of total abstinence, in order to prevent disease progression. This policy has been challenged by epidemiological studies, suggesting that the risk of liver disease and disease progression is lower in modest drinkers than in total abstainers. We revised the literature on the effects of modest alcohol intake on disease burden. Epidemiological data may suffer from several potential biases (recall bias for retrospective analyses, difficulties in the calculation of g/day), limiting their validity. Prospective data suggest that NAFLD patients with regular alcohol intake, although within the safe thresholds, are at higher risk of liver disease progression, including hepatocellular carcinoma; a detrimental effect of modest alcohol drinking is similarly observed in liver disease of viral etiology. Alcohol intake is also a risk factor for extrahepatic cancers, particularly breast, oral, and pharyngeal cancers, with gender difference and no floor effect, which outweigh the possible beneficial effects on cardiovascular system, also derived from retrospective studies. Finally, the negative effects of the calorie content of alcohol on dietary restriction and weight loss, the pivotal intervention to reduce NAFLD burden, should be considered. In summary, the policy of counseling NAFLD patients for alcohol abstinence should be maintained.

Effects of Alcohol Consumption and Metabolic Syndrome on Mortality in Patients With Nonalcoholic and Alcohol-Related Fatty Liver Disease

BACKGROUND & AIMS

Non-alcoholic and alcohol-related fatty liver disease are overlapping diseases in which metabolic syndrome and alcohol consumption each contribute to progressive liver disease. We aimed to assess the effects of alcohol consumption and metabolic syndrome on mortality in individuals with fatty liver.

METHODS

We searched the National Health and Nutrition and Examination Survey III for adults (20-74 years old) with hepatic steatosis, detected by ultrasound, for whom mortality and follow-up data were available. We collected data from the alcohol use questionnaire (self-reported number of days a participant drank alcohol; the number of drinks [10 g alcohol] per day on a drinking day; the number of days the participant had 5 or more drinks) and calculated the average amount of alcohol consumption in drinks/day for each participant during the year preceding enrollment. Excessive alcohol consumption for men was >3 drinks/day and for women was >1.5 drinks/day. We also collected clinical data, and mortality data were obtained from the National Death Index. Demographic and clinical parameters were compared among consumption groups using the χ² test for independence or survey regression models. We used Cox proportional hazard models to identify independent predictors of all-cause and cause-specific mortality.

RESULTS

The study cohort included 4264 individuals with hepatic steatosis (mean age, 45.9 years; 51% male; 76% white; 46% with metabolic syndrome; 6.2% with excessive alcohol use). There was no significant difference in mean age between individuals with vs without excessive alcohol consumption (P=.65). However, overall mortality was significantly higher among participants with excessive alcohol consumption (32.2%) vs participants with non-excessive alcohol use (22.2%) after mean 20 years of follow up (P=.003), as well as after 5 years of follow up. In multivariate analysis, the presence of metabolic syndrome (adjusted hazard ratio [aHR], 1.43; 95% CI, 1.12-1.83) and excessive alcohol consumption (aHR, 1.79; 95% CI, 1.21-2.66) were independently associated with an increased risk of death in individuals with hepatic steatosis; any lower average amount of alcohol consumption was not associated with mortality (all P>.60). In a subgroup analysis, the association of excessive alcohol use with mortality was significant in individuals with metabolic syndrome (aHR, 2.46; 95% CI, 1.40-4.32) but not without it (P=.74).

CONCLUSION

In review of data from the National Health and Nutrition and Examination Survey III, we associated alcohol consumption with increased mortality in participants with fatty liver and metabolic syndrome. These findings indicate an overlap between non-alcoholic and alcohol-related fatty liver disease.

Moderate chronic ethanol consumption exerts beneficial effects on nonalcoholic fatty liver in mice fed a high-fat diet: possible role of higher formation of triglycerides enriched in monounsaturated fatty acids

PURPOSE

Several clinical studies suggested that light-to-moderate alcohol intake could alleviate nonalcoholic fatty liver disease (NAFLD), but the underlying mechanism is still poorly understood.

METHODS

Mice fed a high-fat diet (HFD) were submitted or not to moderate ethanol intake for 3 months (ca. 10 g/kg/day) via drinking water. Biochemical, analytical and transcriptomic analyses were performed in serum and liver.

RESULTS

Serum ethanol concentrations in ethanol-treated HFD mice comprised between 0.5 and 0.7 g/l throughout the experiment. NAFLD improvement was observed in ethanol-treated HFD mice as assessed by reduced serum transaminase activity. This was associated with less microvesicular and more macrovacuolar steatosis, the absence of apoptotic hepatocytes and a trend towards less fibrosis. Liver lipid analysis showed increased amounts of fatty acids incorporated in triglycerides and phospholipids, reduced proportion of palmitic acid in total lipids and higher desaturation index, thus suggesting enhanced stearoyl-coenzyme A desaturase activity. mRNA expression of several glycolytic and lipogenic enzymes was upregulated. Genome-wide expression profiling and gene set enrichment analysis revealed an overall downregulation of the expression of genes involved in collagen fibril organization and leukocyte chemotaxis and an overall upregulation of the expression of genes involved in oxidative phosphorylation and mitochondrial respiratory chain complex assembly. In addition, mRNA expression of several proteasome subunits was upregulated in ethanol-treated HFD mice.

CONCLUSIONS

Moderate chronic ethanol consumption may alleviate NAFLD by several mechanisms including the generation of non-toxic lipid species, reduced expression of profibrotic and proinflammatory genes, restoration of mitochondrial function and possible stimulation of proteasome activity.

Impact of Nutritional Changes on Nonalcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a major global health threat due to its growing incidence and prevalence. It is becoming the leading cause of liver disease in addition to its strong association with cardio-metabolic disease. Therefore, its prevention and treatment are of strong public interest. Therapeutic approaches emphasize lifestyle modifications including physical activity and the adoption of healthy eating habits that intend to mainly control body weight and cardio-metabolic risk factors associated with the metabolic syndrome. Lifestyle interventions may be reinforced by pharmacological treatment in advanced stages, though there is still no registered drug for the specific treatment of NAFLD. The purpose of this review is to assess the evidence available regarding the impact of dietary recommendations against NAFLD, highlighting the effect of macronutrient diet composition and dietary patterns in the management of NAFLD.

Alcoholic and non-alcoholic steatohepatitis: global perspective and emerging science

Alcohol and high-fat diet are two major risk factors responsible for metabolic diseases, which are manifested as steatohepatitis and liver cancer in the liver, and chronic pancreatitis and pancreatic adenocarcinoma (PDAC) in the pancreas. These metabolic diseases are becoming increasingly prevalent around the globe, and more importantly, their two major etiologies commonly coexist to precipitate the disease processes. To highlight the importance of these metabolic diseases, Japanese Society of Gastroenterology (JSGE) and National Institute on Alcoholism and Alcohol Abuse of National Institute of Health cosponsored the JSGE's 7th International Forum jointly held with the 12th International Symposium on ALPD and Cirrhosis. Toward the main theme of "Frontiers in ASH, NASH, NBNC-HCC and PDAC", this platform showcased presentations by 12 invited international and Japanese speakers on brain-gut-liver interactions, emerging mechanisms of ASH and NASH, metabolic reprogramming, and new therapeutic targets for cirrhosis, HCC, and PDAC. This editorial discusses the most recent data on global statistics on how alcohol and obesity impact health and longevity as a prelude to a brief summary of the symposium presentations and discussions, primarily focusing on the first two session themes.

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

The effect of modest alcohol consumption on fibrosis progression in the general population with nonalcoholic fatty liver disease (NAFLD) remains unclear. We examined the association of nonheavy alcohol consumption with worsening of noninvasive fibrosis indices in a large-scale, low-risk population with NAFLD. A cohort study was performed in 58,927 Korean adults with NAFLD and low fibrosis scores who were followed for a median of 4.9 years. Non-, light, and moderate drinkers were defined as 0 g/day, 1-9.9 g/day, and 10-29.9 g/day (10-19.9 g/day for women), respectively. Progression from low to intermediate or high probability of advanced fibrosis was assessed using noninvasive indices including NAFLD fibrosis score (NFS) and Fibrosis-4 Index (FIB-4). A parametric proportional hazards model was used to estimate the multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). During 347,925.4 person-years of follow-up, 5,630 subjects with low FIB-4 progressed to intermediate or high FIB-4. The multivariable-adjusted HRs (95% CI) for worsening of FIB-4 comparing light and moderate drinkers with nondrinkers were 1.06 (0.98-1.16) and 1.29 (1.18-1.40), respectively. Similarly, using NFS, corresponding HRs (95% CI) comparing light and moderate drinkers with nondrinkers were 1.09 (1.02-1.16) and 1.31 (1.23-1.40), respectively. Furthermore, the association of moderate drinkers with worsening of either FIB-4 or NFS remained significant after introducing alcohol use and confounders treated as time-varying covariates. Conclusion: In this large-scale cohort of young and middle-aged individuals with NAFLD, nonheavy alcohol consumption, especially moderate alcohol consumption, was significantly and independently associated with worsening of noninvasive markers of fibrosis, indicating that even moderate alcohol consumption might be harmful.

Alcohol Consumption in Patients with Non-alcoholic Fatty Liver Disease: Convenient vs. Inconvenient Truths

Understanding the role of modest alcohol consumption in patients with non-alcohol induced fatty liver disease (NAFLD) remains a significant challenge, with no clear guidance on counselling regarding alcohol use. Conventionally, the strong association of alcohol excess and development of complications related to chronic liver disease, including hepatocellular carcinoma, has led practitioners to advocate complete abstinence to those with NAFLD. New evidence published in this issue of the Red Journal challenges the historic paradigm by showing that modest, non-binge wine consumption (<70 g/week) associates with significantly lower risk of advanced hepatic fibrosis on biopsy compared with complete abstinence across a well-characterised single centre cohort of nearly 200 patients with NAFLD.

Type and Pattern of Alcohol Consumption is Associated With Liver Fibrosis in Patients With Non-alcoholic Fatty Liver Disease

INTRODUCTION

It is unclear whether low levels of alcohol are harmful in patients with non-alcoholic fatty liver disease (NAFLD). We aimed to determine whether quantity, binge pattern consumption, or type of alcohol was associated with liver fibrosis in patients with NAFLD.

METHODS

Previous and current alcohol consumption was assessed in NAFLD patients undergoing liver biopsy. All subjects currently consumed <210 g per week (male) or <140 g per week (female). Binge consumption was defined as ≥4 standard drinks (female) or ≥5 standard drinks (male) in one sitting. Liver biopsies were scored according to the NASH CRN system with F3/4 fibrosis defined as advanced.

RESULTS

Among 187 patients (24% with advanced fibrosis), the median weekly alcohol consumption was 20 (2.3-60) g over an average of 18 years. Modest consumption (1-70 g per week) was associated with lower mean fibrosis stage compared to lifetime abstainers (p < 0.05) and a decreased risk of advanced fibrosis (OR 0.33, 95% CI 0.14-0.78, p = 0.01). The association with reduced fibrosis was not seen in subjects drinking in a binge-type fashion. Exclusive wine drinkers but not exclusive beer drinkers, had lower mean fibrosis stage and lower odds of advanced fibrosis (OR 0.20, 95% CI 0.06-0.69, p = 0.01), compared to lifetime abstinent subjects. No interaction between gender and alcohol quantity, type, or binge consumption on fibrosis was observed.

DISCUSSION

Modest (1-70 g per week) alcohol consumption, particularly wine in a non-binge pattern, is associated with lower fibrosis in patients with NAFLD. Prospective longitudinal studies into fibrosis progression, cardiovascular outcomes, and mortality are required before clinical recommendations can be made.

Among Patients With Nonalcoholic Fatty Liver Disease, Modest Alcohol Use Is Associated With Less Improvement in Histologic Steatosis and Steatohepatitis

BACKGROUND & AIMS

Cross-sectional studies of patients with nonalcoholic fatty liver disease (NAFLD) have reported a lower prevalence of severe disease among modest drinkers compared with nondrinkers. We collected data from adult participants in the Nonalcoholic Steatohepatitis (NASH) Clinical Research Network to evaluate the longitudinal association between modest use of alcohol and histology findings in patients with NAFLD, using paired liver biopsies collected more than 1 year apart.

METHODS

We studied NASH Clinical Research Network participants 21 years or older, not receiving pharmacologic therapy, from whom 2 or more liver biopsies and data on alcohol use within 2 years of the initial biopsy were available. Alcohol consumption was evaluated at study entry using the Alcohol Use Disorders Identification Test and Skinner Lifetime Drinking History questionnaires. At each follow-up visit participants were asked about alcohol use frequency, number of drinks on a typical day, and frequency of heavy drinking. The association between baseline drinking status and changes in fibrosis stage, NASH histology, and the NAFLD Activity Score and its individual components were evaluated by analysis of covariance. The association between change in drinking status and change in histology was evaluated using adjusted logistic regression.

RESULTS

Of 285 participants (82% white, 70% female, mean age, 47 y) meeting entry criteria, 168 (59%) were modest alcohol users (≤2 drinks/d) and the remaining 117 were abstinent. At baseline, a higher proportion of modest alcohol users were white (86% vs 76% nonwhite) (P = .04) and a lower proportion of modest alcohol users were diagnosed with definite NASH (57% vs 74% without NASH; P = .01). During a mean follow-up period of 47 months between biopsies, nondrinkers had a greater mean reduction in steatosis grade (reduction, 0.49) than modest drinkers (reduction, 0.30; P = .04) and a greater reduction in mean level of aspartate transaminase (reduction, 7 U/L vs an increase of 2 U/L in modest drinkers; P = .04). Modest drinkers had significantly lower odds of NASH resolution compared with nondrinkers (adjusted odds ratio, 0.32; 95% CI, 0.11-0.92; P = .04) on adjusted analysis.

CONCLUSIONS

In a longitudinal analysis of liver biopsies from patients with NAFLD not receiving pharmacologic therapy, modest alcohol use was associated with less improvement in steatosis and level of aspartate transaminase, as well as lower odds of NASH resolution, compared with no use of alcohol.