Modest alcohol consumption is associated with decreased prevalence of steatohepatitis in patients with non-alcoholic fatty liver disease (NAFLD)

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.

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.

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.

Fatty Liver Disease: Diagnosis and Stratification

Nonalcoholic fatty liver disease (NAFLD) is a major public health crisis affecting approximately 25% of the world's population. The spectrum of NAFLD ranges from bland steatosis to steatohepatitis with fibrosis; eventual development of cirrhosis in a subgroup of patients now represents the leading indication for liver transplant in women and in individuals older than 65. The development of noninvasive liver disease assessment tools has led to substantial progress in the diagnosis of NAFLD. Patients with NAFLD are at increased risk of cardiometabolic disease, which should therefore be an important part of the therapeutic approach. This review focuses on diagnosis and risk stratification of NAFLD across the full spectrum of disease, including important considerations in the approach to patients with cirrhosis.

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.

Screening for undiagnosed non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH): A population-based risk factor assessment using vibration controlled transient elastography (VCTE)

The screening for undiagnosed non-alcoholic fatty liver disease and non-alcoholic steatohepatitis (SUNN) study was a population-based screening study that aimed to provide proof of concept to encourage community-level screening and detection for this non-communicable disease. Current screening guidelines do not recommend the routine screening of nonalcoholic fatty liver disease (NAFLD) for asymptomatic populations, so providers are not encouraged to actively seek disease, even in high-risk patients. This study sought to determine whether a self-selecting cohort of asymptomatic individuals would have scores based on vibration controlled transient elastography (VCTE) and controlled attenuation parameter (CAP) significantly correlated to risk factors to suggest that routine screening for high-risk patients should be recommended. The study recruited 1,070 self-selected participants in Houston and Galveston County, Texas, 940 of which were included in final analysis. A pre-screening survey was used to determine eligibility. VCTE-based scores analyzed steatosis and fibrosis levels. Fifty-seven percent of the study population demonstrated steatosis without fibrosis, suggesting NAFLD, while 16% demonstrated both steatosis and fibrosis, suggesting NASH. Statistically significant risk factors included factors related to metabolic syndrome, race, and age, while statistically significant protective factors included consumption of certain foods and exercise. The findings of this study suggest that high-risk individuals should be screened for NAFLD even in the absence of symptoms and that community-based screenings are an effective tool, particularly in the absence of proactive guidelines for providers.

Outcomes of Japanese patients with non-alcoholic fatty liver disease according to genetic background and lifestyle-related diseases

INTRODUCTION AND OBJECTIVES

Genetic background may be involved in the mechanisms of liver injury and the development of non-alcoholic fatty liver disease (NAFLD). However, its contributions to the long-term outcome of NAFLD have been unclear.

METHODS

We enrolled 314 Japanese patients with biopsy-confirmed NAFLD from 2000 to 2018 (161 men [51.3%]; median age, 53 [14-84] years; 114 with advanced fibrosis [37.5%]) in the patients without hepatocellular carcinoma at diagnosis. Genomic DNA was extracted from peripheral blood and single nucleotide polymorphisms (SNPs) were analyzed. Associations of mortality with patatin-like phospholipase 3 (PNPLA3) and aldehyde dehydrogenase 2 (ALDH2) were analyzed. Finally, a subgroup analysis according to lifestyle-related disease was performed.

RESULTS

During the median 7 years of follow-up, 20 patients (6.4%) died (13 liver-related [4.1%] and 7 non-liver-related deaths [2.2%]). Patients with ALDH2 (non-GG genotype) who had reduced alcohol metabolism tended to have a poor prognosis (p = 0.06). Patients carrying both risk SNPs of PNPLA3 (GG) and ALDH2 (non-GG) had a significantly poor prognosis (p = 0.01). In the subgroup analysis, patients with PNPLA3 (GG) who were non-diabetics (p = 0.06) or non-dyslipidemic (p = 0.03), with ALDH2 (non-GG) who were non-dyslipidemic (p = 0.01) or hypertensive (p = 0.03), also had a poor prognosis. The Cox analysis revealed that ALDH2 (non-GG) was associated with a poor prognosis (Hazard ratio: 4.568, 95% Confidence Interval: 1.294-16.131, p = 0.02) similar to the liver function tests.

CONCLUSIONS

Genetic background may affect NAFLD prognosis and ALDH2 SNP could predict the outcome.

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.

Narrative review of current and emerging pharmacological therapies for nonalcoholic steatohepatitis

Nonalcoholic steatohepatitis (NASH) is the most common cause of chronic liver disease today, and it has now emerged as the leading etiology of end-stage liver disease requiring liver transplantation. It is a progressive form of non-alcoholic fatty liver disease which can not only progress to cirrhosis of liver and hepatocellular carcinoma (HCC), but is associated with increased cardiovascular risks too. Despite all the advances in the understanding of the risk factors and the pathogenetic pathways involved in the pathogenesis and progression of NASH, an effective therapy for NASH has not been developed yet. Although lifestyle modifications including dietary modifications and physical activity remain the mainstay of therapy, there is an unmet need to develop a drug or a combination of drugs which can not only reduce the fatty infiltration of the liver, but also arrest the development and progression of fibrosis and advancement to cirrhosis of liver and HCC. The pharmacologic therapies which are being developed target the various components believed to be involved in the pathogenesis of nonalcoholic fatty liver disease (NAFLD)/NASH which includes insulin resistance, lipid metabolism oxidative stress, lipid peroxidation, inflammatory and cell death pathways, and fibrosis. In this review, we summarize the current state of knowledge on pharmacotherapy of NASH, and also highlight the recent developments in the field, for optimizing the management and treatment of NASH.

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.

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.

Diagnosis and management of fatty liver

Globally, the prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing rapidly and constitutes a significant healthcare burden due to associated complications including hepatic (cirrhosis and hepatocellular cancer) and non-hepatic (cardiovascular deaths) disorders. It is closely linked to insulin resistance and metabolic syndrome but moderate alcohol consumption frequently coexists. Recently, genetic polymorphisms were implicated in the development of non-obese NAFLD. Apart from liver biopsy, in order to assess for steatosis, fibrosis and non-alcoholic steatohepatitis (NASH), advances in non-invasive serum tests and elastography have provided similarly accurate, more accessible and safer alternatives for risk stratification. As for treatment in 2020, weight loss and lifestyle modification remain the central strategy. Unfortunately, no pharmacological agents have been approved thus far, but there are a number of potential therapies in the pipeline for fibrosis and NASH. Treatment of underlying metabolic disorders is important. While the term NAFLD was coined in the 1980s, more recent understanding may support a change in nomenclature highlighting its strong metabolic roots.

Interaction between metabolic syndrome and alcohol consumption, risk factors of liver fibrosis: A population-based study

BACKGROUND AND AIMS

Alcohol and metabolic syndrome (MS) coexist frequently as cofactors of liver disease. Previous studies suggest a deleterious effect of MS in advanced alcohol-related liver disease (ArLD). However, it is unknow whether MS can increase the risk of liver fibrosis in early stages of ArLD. The aim of this study was to investigate the effect of MS on liver fibrosis in subjects with alcohol consumption from a population-based cohort.

METHODS

The number of subjects include 1760(58%) of 3014 who were randomly selected from the community consumed alcohol and were classified as current drinkers, divided in moderate (n = 1222) or high-risk drinkers (n = 275) (>21 units/week men, >14 units/week women for high-risk drinkers), or former drinkers (n = 263). Liver fibrosis was estimated by measuring liver stiffness(LS) with transient elastography (TE).

RESULTS

Prevalence of significant LS using cutoff values of TE of 8 and 9.1kPa was increased in high-risk compared with moderate or former drinkers and lifetime abstainers. In subjects with alcohol consumption, LS was associated with male gender, AST, ALT, years of consumption, and MS. In high-risk drinkers, MS and intensity of consumption were the only factors associated with significant LS (OR 3.7 and 4.6 for LS ≥ 8 kPa and 3.9 and 9.2 kPa for LS ≥ 9.1 kPa, respectively). Presence of significant liver fibrosis in the liver biopsy was higher among high-risk as compared with moderate or former drinkers.

CONCLUSION

MS increases the risk of liver fibrosis in subjects with alcohol consumption. Among high-risk drinkers, only MS and consumption of high amount of alcohol are associated with risk of liver fibrosis.

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.

Beyond the Paradigm of Weight Loss in Non-Alcoholic Fatty Liver Disease: From Pathophysiology to Novel Dietary Approaches

Current treatment recommendations for non-alcoholic fatty liver disease (NAFLD) rely heavily on lifestyle interventions. The Mediterranean diet and physical activity, aiming at weight loss, have shown good results in achieving an improvement of this liver disease. However, concerns related to compliance and food accessibility limit the feasibility of this approach, and data on the long-term effects on liver-related outcomes are lacking. Insulin resistance is a central aspect in the pathophysiology of NAFLD; therefore, interventions aiming at the improvement of insulin sensitivity may be preferable. In this literature review, we provide a comprehensive summary of the available evidence on nutritional approaches in the management of NAFLD, involving low-calorie diets, isocaloric diets, and the novel schemes of intermittent fasting. In addition, we explore the harmful role of single nutrients on liver-specific key metabolic pathways, the role of gene susceptibility and microbiota, and behavioral aspects that may impact liver disease and are often underreported in clinical setting. At present, the high variability in terms of study populations and liver-specific outcomes within nutritional studies limits the generalizability of the results and highlights the urgent need of a tailored and standardized approach, as seen in regulatory trials in Non-Alcoholic Steatohepatitis (NASH).

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.

Beverages and Non-alcoholic fatty liver disease (NAFLD): Think before you drink

BACKGROUND & AIMS

Beverages and Non-alcoholic fatty liver disease (NAFLD) both the terms are associated with westernized diet and sedentary lifestyle. Throughout recent decades, dietary changes have boosted demand of beverages to meet the liquid consumption needs, among which rising consumption of several calorie-rich beverages have increased the risk of fatty liver disease. Meanwhile, certain beverages have capacity to deliver many unanticipated health benefits thereby reducing the burden of NAFLD and metabolic diseases. The present review therefore addresses the increasing interconnections between beverages intake among population, dietary patterns and the overall effect of these beverage on the development and prevention of NAFLD. Methods In the present review, some frequently consumed beverage groups have been analyzed in light of their role in the advancement and prevention of NAFLD, including sugar sweetened, hot and alcoholic beverages. The nutritional composition of different beverages makes the progression of NAFLD distinctive.

RESULTS

The ingestion of sugar-rich beverages has demonstrated the metabolic burden and in all cases, raises the risk of NAFLD, while intake of coffee and tea has decreased this risk without any significant adverse effects. In some cases, low to moderate alcohol intake has been shown to minimize the risk of advanced fibrosis and NAFLD-mortality.

CONCLUSION

Together, this review discusses and supports work on new dietary approaches and clinical studies to accomplish nutrition-oriented NAFLD care by improving the drinking habits.

Non-alcoholic fatty liver diseases: current challenges and future directions

Non-alcoholic fatty liver diseases (NAFLD) is rapidly becoming the most common cause of chronic liver disease in Western Countries, and a similar trend is expected in Eastern Countries within the next years. This review focusses on the definition of NAFLD and NASH, possible screening mechanisms and the question who should be screened. Still there is a need for non-invasive diagnostic tools and biomarkers for NASH that can quickly and easily diagnose the severity of NAFLD, monitor liver changes, and identify high risk patients. In addition, treatment strategies are discussed as well as the clientele, who should be treated. There are currently no drugs approved for NAFLD. Successful clinical studies with e.g., obeticholic acid and new substances (e.g., cenicriviroc with anti-inflammatory activity) have already been published. If weight-reducing diets and a change in lifestyle fail in the case of severe obesity, bariatric surgery (e.g., gastric bypass or stomach reduction) should be considered. In the case of manifest type 2 diabetes, metformin can be used as an oral antidiabetic of first choice, and GLP-1 agonists have shown beneficial effects on NAFLD. However, up to now the prevention of overweight and lack of exercise targets the most important risk factors. This review aims to identify therapy relevant risk factors, management strategies, and open questions concerning NAFLD patients.

Natural History of NAFLD

The epidemiology and the current burden of chronic liver disease are changing globally, with non-alcoholic fatty liver disease (NAFLD) becoming the most frequent cause of liver disease in close relationship with the global epidemics of obesity, type 2 diabetes and metabolic syndrome. The clinical phenotypes of NAFLD are very heterogeneous in relationship with multiple pathways involved in the disease progression. In the absence of a specific treatment for non-alcoholic steatohepatitis (NASH), it is important to understand the natural history of the disease, to identify and to optimize the control of factors that are involved in disease progression. In this paper we propose a critical analysis of factors that are involved in the progression of the liver damage and the occurrence of extra-hepatic complications (cardiovascular diseases, extra hepatic cancer) in patients with NAFLD. We also briefly discuss the impact of the heterogeneity of the clinical phenotype of NAFLD on the clinical practice globally and at the individual level.

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.

Second hits exacerbate alcohol-related organ damage: an update

Chronic and excessive alcohol abuse cause direct and indirect detrimental effects on a wide range of body organs and systems and accounts for ~4% of deaths worldwide. Many factors influence the harmful effects of alcohol. This concise review presents newer insights into the role of select second hits in influencing the progression of alcohol-induced organ damage by synergistically acting to generate a more dramatic downstream biological defect. This review specifically addresses on how a lifestyle factor of high fat intake exacerbates alcoholic liver injury and its progression. This review also provides the mechanistic insights into how increasing matrix stiffness during liver injury promotes alcohol-induced fibrogenesis. It also discusses how hepatotropic viral (HCV, HBV) infections as well as HIV (which is traditionally not known to be hepatotropic), are potentiated by alcohol exposure to promote hepatotoxicity and fibrosis progression. Finally, this review highlights the impact of reactive aldehydes generated during alcohol and cigarette smoke coexposure impair innate antimicrobial defense and increased susceptibility to infections. This review was inspired by the symposium held at the 17th Congress of the European Society for Biomedical research on Alcoholism in Lille, France entitled 'Second hits in alcohol-related organ damage'.

Prevalence and Predictors of Nonalcoholic Steatohepatitis Using Multiple Non-Invasive Methods: Data from NHANES III

Objective

Patients with nonalcoholic steatohepatitis (NASH) are at risk for developing cirrhosis and hepatic cancer. Currently, the definitive gold-standard method of diagnosing NASH is a liver biopsy, an invasive and costly method. Our objective was to compare three non-invasive methods of identifying NASH by using data on 10,007 subjects from NHANES III (1988-1994) to determine the prevalence and variables associated with NASH, as defined by each non-invasive method.

Methods

We used ultrasound data to identify subjects with moderate-to-severe hepatic steatosis, of whom we identified the NASH population using either the HAIR score, the NASH liver fat score, or the Gholam score, each of which had been validated with liver biopsy. We performed multinomial logistic regression to compare each NASH population to the normal population (those with no-to-mild hepatic steatosis).

Results

We identified 1136 (9.5%) subjects as having NASH by at least one method and 219 (1.8%) were identified by all 3 methods. Independent of the non-invasive method used, Mexican-Americans (MA) had the highest prevalence of NASH. All three methods identified significant risk factors for NASH (p<0.05), including: elevated waist-to-hip ratio, elevated levels of C-peptide, total cholesterol, or C-reactive protein (CRP).

Conclusion

We conclude that the combined non-invasive methods can help identify candidates with a high likelihood of being diagnosed with NASH. Health care providers can screen people with the combined non-invasive methods for the risk factors and identify candidates for interventions, including exercise and/or referral to biopsy.

[Mixed steatohepatitis: more questions than answers (Part 1)]

The term steatohepatitis is used for a heterogeneous group of diseases of various etiologies, characterized by a similar morphological picture. Earlier the diagnosis of non-alcoholic fatty liver disease implied the exclusion of other causes of steatohepatitis, in recent years it has been suggested that a combination of various etiological variants of steatohepatitis is possible. The review considers the terminological, epidemiological and pathogenetic aspects of the most common combination: metabolic and alcoholic genesis, the issues of the mutual influence of etiopathogenetic factors and the identification of the predominant process. Issues of existing and prospective pathogenetic and symptomatic therapy are discussed in detail. Treatment of steatohepatitis is based on the elimination of known causal factors and lifestyle modification; therapy includes medications, that have been proven to be effective in certain types of steatohepatitis and symptomatic therapy as well.

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.

The effect of moderate alcohol drinking in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is defined by fat accumulation in liver that is not caused by excessive alcohol consumption. Safe limits of alcohol consumption in NAFLD are usually defined as alcohol consumption of less than 210 g per week for men and 140 g per week for women (30 g/day in men, 20 g/day in women) and alcohol consumption below safe limits is generally regarded as moderate alcohol consumption. Many studies have investigated the effects of moderate alcohol consumption on NAFLD patients. Some studies showed that moderate alcohol consumption prevented the progression of fibrosis in the liver, whereas other reports showed worsening of fibrosis in the liver based on serologic, radiologic and liver biopsy findings compared with effects on total abstainers. NAFLD is also thought to be a hepatic manifestation of metabolic syndrome, and when combined with excessive alcohol consumption results in the development of components of metabolic syndrome and systemic harmful effects. The effects of moderate alcohol consumption on NAFLD have yet to be established.

ADH1B∗2 Is Associated With Reduced Severity of Nonalcoholic Fatty Liver Disease in Adults, Independent of Alcohol Consumption

BACKGROUND & AIMS

Alcohol dehydrogenase 1B (ADH1B) is involved in alcohol metabolism. The allele A (ADH1B∗2) of the rs1229984: A>G variant in ADH1B is associated with a higher alcohol metabolizing activity compared to the ancestral allele G (ADH1B∗1). Moderate alcohol consumption is associated with reduced severity of nonalcoholic fatty liver disease (NAFLD), based on histologic analysis, compared with no alcohol consumption. However, it is unclear whether ADH1B∗2 modifies the relationship between moderate alcohol consumption and severity of NAFLD. We examined the association between ADH1B∗2 and moderate alcohol consumption and histologic severity of NAFLD.

METHODS

We collected data from 1557 multiethnic adult patients with biopsy-proven NAFLD enrolled into 4 different studies conducted by the Nonalcoholic Steatohepatitis (NASH) Clinical Research Network. Histories of alcohol consumption were obtained from answers to standardized questionnaires. Liver biopsy samples were analyzed by histology and scored centrally according to the NASH Clinical Research Network criteria. We performed covariate adjusted logistic regressions to identify associations between histologic features of NAFLD severity and moderate alcohol consumption and/or ADH1B∗2.

RESULTS

A higher proportion of Asians/Pacific Islanders/Hawaiians carried the ADH1B∗2 allele (86%) than other racial groups (4%-13%). However, the study population comprised mostly non-Hispanic whites (1153 patients, 74%), so the primary analysis focused on this group. Among them, 433 were moderate drinkers and 90 were ADH1B∗2 carriers. After we adjusted for confounders, including alcohol consumption status, ADH1B∗2 was associated with lower frequency of steatohepatitis (odds ratio [OR], 0.52; P < .01) or fibrosis (odds ratio, 0.69; P = .050) compared with ADH1B∗1. Moderate alcohol consumption (g/d) reduced the severity of NAFLD in patients with ADH1B∗1 or ADH1B∗2. However, ADH1B∗2, compared to ADH1B∗1, was associated with a reduced risk of definite NASH (ADH1B∗2: OR, 0.80; P < .01 vs ADH1B∗1: OR, 0.96; P = .036) and a reduced risk of an NAFLD activity score of 4 or higher (ADH1B∗2: OR, 0.83; P = .012 vs ADH1B∗1: OR, 0.96; P = .048) (P < .01 for the difference in the effect of moderate alcohol consumption between alleles). The relationship between body mass index and NAFLD severity was significantly modified by ADH1B∗2, even after we controlled for alcohol consumption.

CONCLUSIONS

ADH1B∗2 reduces the risk of NASH and fibrosis in adults with NAFLD regardless of alcohol consumption status. ADH1B∗2 might modify the association between high body mass index and NAFLD severity.

Effects of low ethanol consumption on nonalcoholic steatohepatitis in mice

Several recent clinical and epidemiological studies have suggested inhibitory effects of light-to-moderate alcohol consumption on nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH); however, these effects have not been confirmed in experimental studies. Therefore, in this study, we examined the effects of small amounts of ethanol consumption on a mouse model of NASH. Nine-week-old male obese mice (db/db mice) were divided into the following groups: control, high-fat, and low-ethanol groups. The control group was provided ad libitum access to a control liquid diet, the high-fat group was provided access to a high-fat liquid diet, and the low-ethanol group was provided access to the high-fat liquid diet supplemented with 0.1% (w/w) ethanol. Eight weeks later, the mice were sacrificed and serum biochemical, histopathological, and molecular analyses were performed. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were significantly lower in the low-ethanol group than in the high-fat group (p = 0.033 and 0.037, respectively). Liver histopathological analysis showed that intralobular and portal inflammation was significantly milder in the low-ethanol group than in the high-fat group (p = 0.018 and 0.041, respectively). However, no significant differences were observed among the groups in serum insulin and adiponectin levels, hepatic 4-hydroxynonenal (oxidative injury marker) levels, and hepatic cytokine and receptor gene expression levels. In conclusion, the serum transaminase levels and hepatic inflammation in NASH model mice improved after administration of small amounts of ethanol. This study directly demonstrated inhibitory effects of small amounts of ethanol on NASH in mice. The mechanisms underlying these inhibitory effects remain to be elucidated.

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.

Evidence-based clinical advice for nutrition and dietary weight loss strategies for the management of NAFLD and NASH

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide and affects approximately one third of adults in the United States. The disease is becoming a global epidemic as a result of the rising rates of obesity and metabolic disease. Emerging data suggest weight loss of ≥10% overall body weight is beneficial in resolving steatosis and reversing fibrosis. Prospective trials comparing various diets are limited by lack of sufficient power as well as pre- and post-treatment histopathology, and therefore no specific diet is recommended at this time. In this narrative review we examine the pathophysiology behind specific macronutrient components that can either promote or reverse NAFLD to help inform more specific dietary recommendations. Overall, the data supports reducing saturated fat, refined carbohydrates, and red and processed meats in the diet, and increasing the consumption of plant-based foods. Diets that incorporate these recommendations include plant-based diets such as the Dietary Approaches to Stop Hypertension, Mediterranean, vegetarian, and vegan diets.

A Description of Risk Factors for Non-alcoholic Fatty Liver Disease in the Southern Community Cohort Study: A Nested Case-Control Study

Background: Non-alcoholic fatty liver disease (NAFLD) is associated with obesity and hypercholesterolemia. In addition, total fat and folate intake have been associated with NAFLD.

Aims: We investigated risk factors for NAFLD among individuals of largely low socioeconomic status, and whether these associations differed by race.

Methods: A nested case-control study was conducted within the Southern Community Cohort Study. Through linkage of the cohort with Centers for Medicare and Medicaid Services, International Classification of Diseases, Ninth Revision, Clinical Modification codes were used to identify incident NAFLD cases. Controls were matched 4:1 to cases on enrollment age, sex, and race. A logistic regression was used to estimate odds ratios for the associations of NAFLD with covariates of interest.

Results: Neither total fat nor folate intake was significantly associated with NAFLD. Hypercholesterolemia (odds ratio 1.21) and body mass index (75th vs. 25th percentile) for blacks (odds ratio 1.96) and whites (odds ratio 2.33) were associated with an increased risk of non-alcoholic fatty liver disease. No significant interaction with race for any of the studied variables was noted.

Conclusions: Both hypercholesterolemia and increasing body mass index, but not total fat and folate intake, were risk factors for NAFLD in the Southern Community Cohort Study.

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.

Light-to-Moderate Alcohol Consumption Is Associated With Increased Risk of Type 2 Diabetes in Individuals With Nonalcoholic Fatty Liver Disease: A Nine-Year Cohort Study

OBJECTIVE

This study explored the association between light-to-moderate alcohol consumption (LMAC) and risk of type 2 diabetes mellitus (T2DM) in individuals with nonalcoholic fatty liver disease (NAFLD).

METHODS

A 9-year cohort study was performed among Chinese men who underwent their annual health checkups between 2009 and 2018. NAFLD was diagnosed based on abdominal ultrasound with exclusion of excess alcohol intake and other causes of liver disease. Logistic regression and Cox proportional regression analyses were applied to identify the risk of prevalent and incident T2DM.

RESULTS

Of the 7,079 participants enrolled, 243 had T2DM at baseline and 630 developed T2DM during the 45,456 person-years follow-up. Both at the baseline and by the end of the follow-up, LMAC was associated with a decreased risk of prevalent T2DM in NAFLD-free participants but with a significantly increased risk in patients with NAFLD. LMAC was also associated with a decreased risk of incident T2DM in NAFLD-free participants. The adjusted hazard ratios (95% confidence interval) of incident T2DM were 0.224 (0.115-0.437) and 0.464 (0.303-0.710) for NAFLD-free light drinkers and NAFLD-free moderate drinkers, respectively. Nondrinking, light-drinking, and moderate-drinking patients with NAFLD all showed significantly increased risks of incident T2DM. Compared with NAFLD-free nondrinkers, the adjusted hazard ratios (95% confidence interval) of incident T2DM were 1.672 (1.336-2.092), 2.642 (1.958-3.565), and 2.687 (2.106-3.427) for nondrinking, light-drinking, and moderate-drinking patients with NAFLD, respectively.

DISCUSSION

LMAC decreased the risks of prevalent and incident T2DM in NAFLD-free participants. LMAC, however, was associated with an increased risk of T2DM in patients with NAFLD (ClinicalTrials.gov number: NCT03847116).

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.

Nonalcoholic Fatty Liver Disease: An Important Consideration for Primary Care Providers in Hawai'i

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. NAFLD is a broad term for both non-alcoholic fatty liver (NAFL), which describes simple fatty liver without inflammation, and non-alcoholic steatohepatitis (NASH), the more severe phenotype with hepatocellular inflammation. The population of Hawai'i is particularly vulnerable to the NAFLD and obesity epidemics due to its large proportions of high-risk ethnic minorities exposed to varying degrees of westernization. Unfortunately, primary care providers (PCPs) often face a lack of awareness on the diagnosis and disease spectrum of NAFLD. Early initiation of treatment for NAFLD is crucial to slow its progression and prevent liver-related morbidity and mortality. This review aims to raise awareness for NAFLD among PCPs in Hawai'i by summarizing the disease's epidemiology, diagnosis, and treatment. The diagnostic workup of NAFLD in the primary care setting involves exclusion of other liver disease etiologies and staging assessment of fibrosis and steatosis through non-invasive means such as serum biomarkers or elastography. Patients with overt signs and symptoms of cirrhosis or a high likelihood of advanced hepatic fibrosis should be referred to liver disease specialists. The role of PCPs in NAFLD management involves facilitating weight loss through therapeutic lifestyle modifications and treatment of comorbid cardiovascular conditions. Evidence-based pharmacologic therapies for NAFLD are available, such as vitamin E and pioglitazone, with more currently in development.

Prevalence and risk factors of fatty liver in Portuguese adults

BACKGROUND

Prevalence of fatty liver (FL) and nonalcoholic fatty liver disease (NAFLD) depends mainly on obesity, diabetes and genetic factors. FL and NAFLD prevalence was evaluated in Portuguese adult population and correlated with several risk factors and related mortality data, within the same period.

MATERIALS AND METHODS

A cross-sectional, population-based multicenter study, voluntary and randomly selected in 834 Portuguese adults (18-79 years). Participants were evaluated after 12-hour fasting. Anthropometric data, past history including alcohol consumption, and associated diseases were registered. Blood samples were collected for biochemical testing. Dietary intake was evaluated using a semi-quantitative food frequency questionnaire. Presence of FL was evaluated using ultrasound, and NAFLD was diagnosed after exclusion of other causes for liver disease.

RESULTS

Adjusted prevalence of FL and NAFLD was 37.8% and 17.0%, respectively. FL individuals were older, more frequently males, with increased probability of having obesity, diabetes or harmful alcohol consumption (HAC). NAFLD individuals were also older, but had a similar sex distribution and an increased probability of obesity and diabetes. In both groups, no differences were found regarding dietary pattern or physical activity. During the same time period, nonalcoholic steatohepatitis (NASH) liver-related deaths in Portugal were 0.105/100 000, while alcohol-related liver disease mortality was 6.790/100 000.

CONCLUSION

The large spectrum of FL was present in more than one third of the population, although only less than half could be classified as NAFLD. Other significant risk factors, such as HAC, are probably implicated in FL, explaining the low NASH-related mortality compared with the high alcohol-related mortality during the same time period.

Combined alcoholic and non-alcoholic steatohepatitis

While metabolic syndrome and alcohol consumption are the two main causes of chronic liver disease, one of the two conditions is often predominant, with the other acting as a cofactor of morbimortality. It has been shown that obesity and alcohol act synergistically to increase the risk of fibrosis progression, hepatic carcinogenesis and mortality, while genetic polymorphisms can strongly influence disease progression. Based on common pathogenic pathways, there are several potential targets that could be used to treat both diseases; based on the prevalence and incidence of these diseases, new therapies and clinical trials are needed urgently.

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.

Epidemiology of non-alcoholic and alcoholic fatty liver diseases

Liver diseases are fast emerging as global health priorities. Fatty liver is described in the setting of non-alcoholic fatty liver disease (NAFLD) as well as alcoholic liver disease (ALD), the pathogenesis of excess fat being different in the two conditions while both are important components of the changing face of burden of liver diseases worldwide. They are intimately associated with a globalized economy and an increasingly homogenous socio- cultural order with a westernized lifestyle. The accompanying adoption of a progressively sedentary life, consumption of diet dense in calories facilitate development of NAFLD while a spiraling upward trend in alcohol use along with earlier age of drinking as well as increased amount of per capita alcohol consumption increases the prevalence of ALD globally. Adverse health outcomes in NAFLD as well as ALD are caused not only by progressive liver fibrosis that is the most significant factor for liver related and all-cause mortality in both but also by non-liver (cardiovascular, cancer, accidents, neurological) clinical outcomes that calls for a multidisciplinary and social approach to these conditions. We present here an outline of facets of epidemiology of both NAFLD as well as ALD along with its' public health implications. A broad-based integrated approach that incorporates social, behavioral as well as biological targets need to be undertaken at a health system level in a planned manner for these evolving liver health priorities that disproportionately challenges the low- and middle-income countries of Asia, South America and Africa.

Recent advances in alcohol-related liver disease (ALD): summary of a Gut round table meeting

Alcohol-related liver disease (ALD), which includes a range of disorders of different severity and is one of the most prevalent types of liver disease worldwide, has recently regained increased attention. Among other reasons, the realisation that any alcohol intake, regardless of type of beverage represents a health risk, and the new therapeutic strategies tested in recently published or undergoing clinical trials spur scientific interest in this area.In April 2019, Gut convened a round table panel of experts during the European Association for the Study of the Liver International Liver Congress in Vienna to discuss critical and up-to-date issues and clinical trial data regarding ALD, its epidemiology, diagnosis, management, pathomechanisms, possible future treatments and prevention. This paper summarises the discussion and its conclusions.