Synergistic association between alcohol intake and body mass index with serum alanine and aspartate aminotransferase levels in older adults: the Rancho Bernardo Study

Alcohol-associated liver disease and behavioral and medical cofactors: unmet needs and opportunities

Chronic liver disease is a leading cause of death in the US and is often preventable. Rising burden, cost, and fatality due to liver disease are driven by intensified alcohol use in the US population and the contributions of comorbid conditions. This mini-review focuses on the topic of liver health in the context of chronic, behavioral cofactors of disease, using research-based examples from the Brown University Center for Addiction and Disease Risk Exacerbation (CADRE). Our aim is to illustrate the current challenges and opportunities in clinical research addressing liver health in the context of behavioral and medical comorbidity and to highlight next steps in this crucial area of public health research and clinical care.

New Nomenclature for Nonalcoholic Fatty Liver Disease: Understanding Metabolic Dysfunction-Associated Steatotic Liver Disease, Metabolic Dysfunction- and Alcohol-Associated Liver Disease, and Their Implications in Clinical Practice

In June 2023, under the patronage of the American Association for Study of Liver Disease, the European Association for Study of the Liver, and the Asociación Latinoamericana para el Estudio del Hígado with the involvement of 236 participants from around the world, a new nomenclature and definition for nonalcoholic fatty liver disease (NAFLD) has been proposed. Metabolic dysfunction-associated steatotic liver disease (MASLD) was defined as presence of hepatic steatosis and at least one of the cardiometabolic risk factors with alcohol intake less than 140 g/wk for women and 210 g/wk for men and no other causes of steatosis. A new entity called combined metabolic dysfunction- and alcohol-associated liver disease (MetALD) was created outside of pure MASLD for patients with metabolic dysfunction and alcohol intake greater than that allowed for MASLD (i.e., 140-350 g/wk for women and 210-420 g/wk for men). Recent studies have confirmed a 95% overlap between NAFLD and the new MASLD diagnostic criteria. Natural history, biomarkers, and thresholds of alcohol intake in MetALD group remains to be studied and validated.

Independent and additive effects of binge drinking and obesity on liver enzymes: a cross-sectional analysis using the Korean National Health Insurance Service data

Background

Binge drinking (BD) has been associated with elevated liver enzymes, but the joint association of BD and adiposity with liver enzymes is understudied. We aimed to examine the combined association of BD and obesity with elevated liver enzymes.

Methods

Data were obtained from 285,600 patients in the Korean National Health check-up program during 2009-2015. Level I BD (BD I) was defined as alcohol consumption of >60 g (men) or >40 g (women) on one occasion in the previous year. High-intensity BD (HIBD) corresponded to at least two times the BD I levels. General and abdominal obesity were defined by body mass index and waist circumference. Logistic regression was used to examine the independent and joint associations of BD and obesity with elevated alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyl transferase (GGT) levels. Relative excess risk (RERI), attributable proportion (AP), and synergy index (SI) were calculated to estimate the additive interaction effects.

Results

The mean age was 42.1 ± 0.03 years and 50.2% were women. Elevated ALT [odds ratio (OR) 1.09, 95% confidence interval (CI) 1.02-1.16], AST (OR 1.16, 95% CI 1.11-1.23), and GGT (OR 1.84, 95% CI 1.05-1.94) were associated with HIBD. Higher odds of elevated ALT (OR 3.57, 95% CI 3.43-3.71), AST (OR 3.47, 95% CI 3.37-3.58), and GGT (OR 2.10, 95% CI 1.98-2.12) were observed in individuals with general obesity. A similar trend was observed for abdominal obesity. The RERI, AP, and SI for the interaction effect of BD and general obesity were 23%, 7%, and 13% for elevated AST levels, and 67%, 24%, and 58% for elevated GGT levels, respectively. Similar effects were observed for the interaction between BD and abdominal obesity.

Conclusions

Obesity aggravated the odds of elevated liver AST and GGT levels in HIBD.

Contribution of alcohol use to the global burden of cirrhosis and liver cancer from 1990 to 2019 and projections to 2044

BACKGROUND

Identifying the temporal trends of cirrhosis and liver cancer attributable to alcohol use in both the past and the future can formulate the control strategies.

METHODS

Data on cirrhosis and liver cancer attributable to alcohol use from 1990 to 2019, including mortality and disability-adjusted life year (DALY) rates were collected from the 2019 Global Burden of Disease (GBD) study. To analyze the temporal trends, the average annual percentage change (AAPC) was calculated, and the Bayesian age-period-cohort model was applied.

RESULT

Deaths and DALY of cirrhosis and liver cancer attributable to alcohol use increased year by years, but the age-standardized death rate (ASDR) and age-standardized DALY rate declined or remained stable from 1990 to 2019 in most regions of the world. The burden of cirrhosis attributable to alcohol increased in low-middle social-development index (SDI) regions, while the burden of liver cancer increased in high-SDI regions. Eastern Europe and Central Asia have the highest burden of cirrhosis and liver cancer caused by alcohol use. Deaths and DALYs are mainly distributed in people aged 40+ years, but there is an increasing trend in people aged under 40 years. New deaths from cirrhosis and liver cancer attributable to alcohol use are predicted to increase in the next 25 years, but the ASDR of cirrhosis in males will increase slightly.

CONCLUSIONS

Although the age-standardized rate of cirrhosis and liver cancer due to alcohol use have decreased, the absolute burden increased and will continue to increase. Therefore, alcohol control measures should be further strengthened and improved through effective national policies.

Associations between Liver Enzymes, Lifestyle Risk Factors and Pre-Existing Medical Conditions in a Population-Based Cross-Sectional Sample

While alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT) enzymes are commonly used indicators of liver dysfunction recent studies have suggested that these may also serve as predictive biomarkers in the assessment of extrahepatic morbidity. In order to shed further light on the interactions between serum liver enzyme abnormalities, factors of lifestyle and health status we examined ALT and GGT activities in a population-based sample of 8743 adult individuals (4048 men, 4695 women from the National FINRISK 2002 Study, mean age 48.1 ± 13.1 years) with different levels of alcohol drinking, smoking, physical activity, body weight and the presence or absence of various pre-existing medical conditions. The assessments also included laboratory tests for inflammation, lipid status and fatty liver index (FLI), a proxy for fatty liver. The prevalence of ALT and GGT abnormalities were significantly influenced by alcohol use (ALT: p < 0.0005 for men; GGT: p <0.0005 for both genders), smoking (GGT: p <0.0005 for men, p =0.002 for women), adiposity (p < 0.0005 for all comparisons), physical inactivity (GGT: p <0.0005; ALT: p <0.0005 for men, p <0.05 for women) and coffee consumption (p <0.0005 for GGT in both genders; p <0.001 for ALT in men). The total sum of lifestyle risk factor scores (LRFS) influenced the occurrence of liver enzyme abnormalities in a rather linear manner. Significantly higher LRFS were observed in the subgroups of individuals with pre-existing medical conditions when compared with those having no morbidities (p <0.0005). In logistic regression analyses adjusted for the lifestyle factors, both ALT and GGT associated significantly with fatty liver, diabetes and hypertension. GGT levels also associated with coronary heart disease, angina pectoris, cardiac insufficiency, cerebrovascular disease, asthma and depression. Combinations of abnormal ALT and GGT activities significantly increased the odds for hypertension coinciding with abnormalities in biomarkers of inflammation, lipid status and FLI. The data indicates that ALT and GGT activities readily respond to unfavorable factors of lifestyle associating also with a wide array of pre-existing medical conditions. The data supports close links between both hepatic and extrahepatic morbidities and lifestyle risk factors and may open new insights on a more comprehensive use of liver enzymes in predictive algorithms for assessing mechanistically anchored disease conditions.

Predictive risk markers in alcoholism

The medical disorders of alcoholism rank among the leading public health problems worldwide and the need for predictive and prognostic risk markers for assessing alcohol use disorders (AUD) has been widely acknowledged. Early-phase detection of problem drinking and associated tissue toxicity are important prerequisites for timely initiations of appropriate treatments and improving patient's committing to the objective of reducing drinking. Recent advances in clinical chemistry have provided novel approaches for a specific detection of heavy drinking through assays of unique ethanol metabolites, phosphatidylethanol (PEth) or ethyl glucuronide (EtG). Carbohydrate-deficient transferrin (CDT) measurements can be used to indicate severe alcohol problems. Hazardous drinking frequently manifests as heavy episodic drinking or in combinations with other unfavorable lifestyle factors, such as smoking, physical inactivity, poor diet or adiposity, which aggravate the metabolic consequences of alcohol intake in a supra-additive manner. Such interactions are also reflected in multiple disease outcomes and distinct abnormalities in biomarkers of liver function, inflammation and oxidative stress. Use of predictive biomarkers either alone or as part of specifically designed biological algorithms helps to predict both hepatic and extrahepatic morbidity in individuals with such risk factors. Novel approaches for assessing progression of fibrosis, a major determinant of prognosis in AUD, have also been made available. Predictive algorithms based on the combined use of biomarkers and clinical observations may prove to have a major impact on clinical decisions to detect AUD in early pre-symptomatic stages, stratify patients according to their substantially different disease risks and predict individual responses to treatment.

Current Treatment Options, Including Diet, Exercise, and Medications: The Impact on Histology

Paralleling the rise in obesity and diabetes, nonalcoholic fatty liver disease (NAFLD) is now the most prevalent chronic liver disease worldwide. Nonalcoholic steatohepatitis (NASH), the progressive form of NAFLD, may progress to cirrhosis, hepatic decompensation, and hepatocellular carcinoma. Despite its public health treat, no approved pharmacotherapies for NAFLD/NASH currently exist. Although the armamentarium of therapies for NASH is limited, current treatment options include life-style modification and the use of medications to treat metabolic comorbidities. This review addresses current approaches to the treatment of NAFLD/NASH, including the impact of diet, exercise, and available pharmacotherapies on the histologic features of liver injury.

Research Priorities for Precision Medicine in NAFLD

NAFLD is a multisystem condition and the leading cause of chronic liver disease globally. There are no approved NAFLD-specific dugs. To advance in the prevention and treatment of NAFLD, there is a clear need to better understand the pathophysiology and genetic and environmental risk factors, identify subphenotypes, and develop personalized and precision medicine. In this review, we discuss the main NAFLD research priorities, with a particular focus on socioeconomic factors, interindividual variations, limitations of current NAFLD clinical trials, multidisciplinary models of care, and novel approaches in the management of patients with NAFLD.

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.

In vitro, in vivo, and in silico analysis of synbiotics as preventive interventions for lipid metabolism in ethanol-induced adipose tissue injury

The risk of alcoholic liver disease (ALD) is increased by excessive ethanol drinking. For the prevention of ALD, the effects of ethanol on the liver, adipose tissue, and gut are crucial. Interestingly, garlic and a few probiotic strains can protect against ethanol-induced hepatotoxicity. However, the relationship between adipose tissue inflammation, Kyolic aged garlic extract (AGE), and Lactobacillus rhamnosus MTCC1423 in developing ALD is unknown. Therefore, the present study explored the effect of synbiotics (a combination of prebiotics and probiotics) on adipose tissue to prevent ALD. To investigate the efficacy of synbiotics administration on adipose tissue in preventing ALD, in vitro (3T3-L1 cells, N = 3) groups: control, control + LPS (lipopolysaccharide), ethanol, ethanol + LPS, ethanol + synbiotics, ethanol + synbiotics + LPS; in vivo (Wistar male rats, N = 6) groups: control, ethanol, pairfed, ethanol + synbiotics and in silico experiments were conducted. Lactobacillus multiplies in accordance with the growth curve when exposed to AGE. Additionally, Oil red O staining and scanning electron microscopy (SEM) demonstrated that synbiotics therapy maintained the morphology of adipocytes in the alcoholic model. In support of the morphological changes, quantitative real-time PCR demonstrated overexpression of adiponectin and downregulation of leptin, resistin, PPARγ, CYP2E1, iNOS, IL-6, and TNF-α after administration of synbiotics compared to the ethanol group. In addition, MDA estimation by high-performance liquid chromatography (HPLC) indicated that the synbiotics treatment reduced oxidative stress in rat adipose tissue. Consequently, the in-silico analysis revealed that AGE inhibited the C-D-T networks as PPARγ acting as the main target protein. The current study demonstrates that using synbiotics improves adipose tissue metabolism in ALD.

Identification of predictors for the comprehensive clinical risk and severity of coronary lesions of acute coronary syndrome

Background

Acute coronary syndrome (ACS) is the most common cause of death in patients with coronary artery disease. The aim of the study was to identify the predictors of both comprehensive clinical risk and severity of coronary lesions by comprehensive use of GRACE and SYNTAX scores in patients with ACS.

Methods

Clinical data of 225 ACS patients who underwent coronary angiography between 2015 and 2016 were collected. Multiple logistic regression analysis (stepwise) was used to identify the predictors. The predictive ability of predictors and the model were determined using receiver operating characteristics analyses.

Results

Multivariable logistic regression analyses showed that high aspartate aminotransferase (AST) predicted the comprehensive clinical risk with odds ratios (ORs) and 95% confidence intervals (CIs) of 1.011 (1.002–1.021). High total cholesterol (TC) and red blood cell distribution width (RDW) predicted the severity of coronary lesions with ORs and 95% CIs of 1.517 (1.148–2.004) and 1.556 (1.195–2.028), respectively. Low prealbumin predicted both severity of coronary lesions and comprehensive clinical risk of ACS patients with ORs and 95% CIs of 0.743 (0.672–0.821) and 0.836 (0.769–0.909), respectively. The model with a combination of prealbumin and AST had the highest predictive efficacy for comprehensive clinical risk, and the combination of prealbumin, TC, and RDW had the highest predictive efficacy for the severity of coronary lesions. The sensitivity and specificity, and the optimal cut-off values of these four indexes were determined.

Conclusions

Four predictors for the comprehensive clinical risk and severity of coronary lesions of ACS were identified, which provided important information for the early diagnosis and appropriate treatment of ACS.

Global epidemiology of alcohol-associated cirrhosis and HCC: trends, projections and risk factors

Heavy alcohol consumption is a major cause of morbidity and mortality. Globally, alcohol per-capita consumption rose from 5.5 litres in 2005 to 6.4 litres in 2016 and is projected to increase further to 7.6 litres in 2030. In 2019, an estimated 25% of global cirrhosis deaths were associated with alcohol. The global estimated age-standardized death rate (ASDR) of alcohol-associated cirrhosis was 4.5 per 100,000 population, with the highest and lowest ASDR in Africa and the Western Pacific, respectively. The annual incidence of hepatocellular carcinoma (HCC) among patients with alcohol-associated cirrhosis ranged from 0.9% to 5.6%. Alcohol was associated with approximately one-fifth of global HCC-related deaths in 2019. Between 2012 and 2017, the global estimated ASDR for alcohol-associated cirrhosis declined, but the ASDR for alcohol-associated liver cancer increased. Measures are required to curb heavy alcohol consumption to reduce the burden of alcohol-associated cirrhosis and HCC. Degree of alcohol intake, sex, older age, obesity, type 2 diabetes mellitus, gut microbial dysbiosis and genetic variants are key factors in the development of alcohol-associated cirrhosis and HCC. In this Review, we discuss the global epidemiology, projections and risk factors for alcohol-associated cirrhosis and HCC.

Meta-analytic evidence for a sex-diverging association between alcohol use and body mass index

Alcohol use is an important health issue and has been suggested to contribute to the burden produced by obesity. Both alcohol use and obesity are subject to sex differences. The available studies on the relationship between alcohol use and body mass index (BMI) report inconsistent results with positive, negative, and null findings which requests a meta-analytic approach. Therefore, we conducted a meta-analysis of case-control, cohort, and cross-sectional studies. The systematic literature search and data extraction was performed by 3 independent raters. We conducted sex-separated meta-analyses and -regressions to investigate how alcohol consumption associates with BMI. Our systematic literature search resulted in 36 studies with 48 data sets (N_men = 172,254; k_men = 30; N_women = 24,164; k_women = 18; N_{unknown sex} = 672,344; k_{unknown sex} = 24). Alcohol use was associated with higher BMI in men (g = 0.08 [0.07; 0.09]) and lower BMI in women (g = - 0.26 [- 0.29; - 0.22]). Moreover, we found the amount of daily alcohol intake in men (β = 0.001 [0.0008; 0.0014]) and ethnicity in women (g[Caucasians] = - 0.45 versus g[Asians] = - 0.05; z = 11.5, p < 0.0001) to moderate these effects. We here identified sex-diverging relationships between alcohol use and BMI, found daily alcohol intake and ethnicity to sex-specifically moderate these effects, and argue that sex-specific choice of beverage type and higher amount of daily alcohol use in men than in women account for these observations. Future research is needed to provide empirical evidence for the underlying mechanisms.

Pathogenesis of Alcohol-Associated Liver Disease

Excessive alcohol consumption is a global healthcare problem with enormous social, economic, and clinical consequences. While chronic, heavy alcohol consumption causes structural damage and/or disrupts normal organ function in virtually every tissue of the body, the liver sustains the greatest damage. This is primarily because the liver is the first to see alcohol absorbed from the gastrointestinal tract via the portal circulation and second, because the liver is the principal site of ethanol metabolism. Alcohol-induced damage remains one of the most prevalent disorders of the liver and a leading cause of death or transplantation from liver disease. Despite extensive research on the pathophysiology of this disease, there are still no targeted therapies available. Given the multifactorial mechanisms for alcohol-associated liver disease pathogenesis, it is conceivable that a multitherapeutic regimen is needed to treat different stages in the spectrum of this disease.

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.

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.

Characterizing the risk interplay between alcohol intake and body mass index on cirrhosis morbidity

BACKGROUND AND AIMS

It is thought that alcohol intake and body mass index (BMI) interact supra-additively to modulate the risk of cirrhosis, but evidence for this phenomenon is limited. We investigated the interrelationship between alcohol and BMI on the incidence of cirrhosis morbidity for participants of the United Kingdom Biobank (UKB) study.

APPROACH AND RESULTS

The primary outcome was the cumulative incidence of cirrhosis morbidity, defined as a first-time hospital admission for cirrhosis (with noncirrhosis mortality incorporated as a competing risk). All UKB participants without a previous hospital admission for cirrhosis were included in the analysis. We determined the ratio of the 10-year cumulative incidence in harmful drinkers versus safe drinkers according to BMI. We also calculated the excess cumulative incidence at 10 years for individuals with obesity and/or harmful alcohol compared to safe drinkers with a healthy BMI of 20-25.0 kg/m² . A total of 489,285 UK Biobank participants were included, with mean of 10.7 person-years' follow-up. A total of 2070 participants developed the primary outcome, equating to a crude cumulative incidence of 0.36% at 10 years (95% CI:0.34-0.38). The 10-year cumulative incidence was 8.6 times higher for harmful (1.38%) versus safe drinkers (0.16%) if BMI was healthy. Conversely, it was only 3.6 times higher for obese participants (1.99% vs. 0.56%). Excess cumulative incidence was 1.22% (95% CI:0.89-1.55) for harmful drinkers with a healthy BMI, 0.40% (95% CI:0.34-0.46) for obese individuals drinking at safe levels, and 1.83% (95% CI:1.46-2.20) for obese harmful drinkers (all compared to safe drinkers with a healthy BMI).

CONCLUSIONS

Alcohol intake and obesity are independent risk factors for cirrhosis morbidity, but they do not interact supra-additively to modulate the cumulative incidence of this outcome.

Mediterranean Diet and Fatty Liver Risk in a Population of Overweight Older Italians: A Propensity Score-Matched Case-Cohort Study

Hepatic steatosis, often known as fatty liver, is the most common hepatic disease in Western countries. The latest guidelines for the treatment of nonalcoholic fatty liver disease emphasize lifestyle measures, such as changing unhealthy eating patterns. Using a propensity score-matching approach, this study investigated the effect of adhering to a Mediterranean diet (MedDiet) on fatty liver risk in an older population (≥65 years) from Southern Italy. We recruited 1.403 subjects (53.6% men, ≥65 years) who completed a food frequency questionnaire (FFQ) and underwent clinical assessment between 2015 and 2018. For the assessment of the liver fat content, we applied the Fatty Liver Index (FLI). To evaluate the treatment effect of the MedDiet, propensity score matching was performed on patients with and without FLI > 60. After propensity score-matching with the MedDiet pattern as treatment, we found a higher consumption of red meat (p = 0.04) and wine (p = 0.04) in subjects with FLI > 60. Based on the FLI, the inverse association shown between adherence to the MedDiet and the risk of hepatic steatosis shows that the MedDiet can help to prevent hepatic steatosis. Consuming less red and processed meat, as well as alcoholic beverages, may be part of these healthy lifestyle recommendations.

Deficiency of Cathelicidin Attenuates High-Fat Diet Plus Alcohol-Induced Liver Injury through FGF21/Adiponectin Regulation

Alcohol consumption and obesity are known risk factors of steatohepatitis. Here, we report that the deficiency of CRAMP (cathelicidin-related antimicrobial peptide—gene name: Camp) is protective against a high-fat diet (HFD) plus acute alcohol (HFDE)-induced liver injury. HFDE markedly induced liver injury and steatosis in WT mice, which were attenuated in Camp^–/– mice. Neutrophil infiltration was lessened in the liver of Camp^–/– mice. HFDE feeding dramatically increased epididymal white adipose tissue (eWAT) mass and induced adipocyte hypertrophy in WT mice, whereas these effects were attenuated by the deletion of Camp. Furthermore, Camp^–/– mice had significantly increased eWAT lipolysis, evidenced by up-regulated expression of lipolytic enzymes, adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL). The depletion of Camp also increased uncoupling protein 1 (UCP1)-dependent thermogenesis in the brown adipose tissue (BAT) of mice. HFDE fed Camp^–/– mice had elevated protein levels of fibroblast growth factor 21 (FGF21) in the eWAT, with an increased adiponectin production, which had been shown to alleviate hepatic fat deposition and inflammation. Collectively, we have demonstrated that Camp^–/– mice are protected against HFD plus alcohol-induced liver injury and steatosis through FGF21/adiponectin regulation. Targeting CRAMP could be an effective approach for prevention/treatment of high-fat diet plus alcohol consumption-induced steatohepatitis.

Non-alcoholic fatty liver disease: A patient guideline

This patient guideline is intended for all patients at risk of or living with non-alcoholic fatty liver disease (NAFLD). NAFLD is the most frequent chronic liver disease worldwide and comes with a high disease burden. Yet, there is a lot of unawareness. Furthermore, many aspects of the disease are still to be unravelled, which has an important impact on the information that is given (or not) to patients. Its management requires a close interaction between patients and their many healthcare providers. It is important for patients to develop a full understanding of NAFLD in order to enable them to take an active role in their disease management. This guide summarises the current knowledge relevant to NAFLD and its management. It has been developed by patients, patient representatives, clinicians and scientists and is based on current scientific recommendations, intended to support patients in making informed decisions.

Impact of body mass and alcohol consumption on all-cause and liver mortality in 240 000 adults in the United States

INTRODUCTION

Nationally representative studies of the combined impact of drinking and body mass (BMI) on mortality outcomes are unavailable. We investigate whether both act together to elevate risk of all-cause or liver mortality.

METHODS

We obtained self-reported histories of drinking and BMI from 129 098 women (mean age 47.2 years) and 102 568 men (mean age 45.6 years) ≥18 years interviewed from 1997 to 2004 in the National Health Interview Survey and related these data to the deaths that occurred by 31 December 2006 (women = 8486; men = 7819 deaths). Death hazards among current drinkers in different BMI groups were adjusted for age, education, race and smoking.

RESULTS

Obese (≥30 kg m-2 ) adults with consumption of >40 g day-1 (women) or >60 g day-1 (men) pure ethanol were at risk of increased mortality from all-cause and chronic liver disease (P trend <0.0001). For heavy drinkers with BMI ≥30 kg m-2 , each 5 kg m-2 higher BMI was associated with an elevated all-cause mortality in men (hazard ratios 1.27, 95% confidence interval [CI]: 1.16-1.40) and women (1.12, [1.02-1.24]). The excess risk due to interaction was more pronounced in men (7.30, [3.60-11.00]) than women (2.90, [0.50-5.30]).

DISCUSSION AND CONCLUSIONS

Obesity and excess alcohol are both related to all-cause and liver mortality-the latter with evidence of a supra-additive interaction between the risk factors. The presence of both factors in the same population and their impact should inform treatment, public health policies and research.

The combined effect of alcohol and body mass index on risk of chronic liver disease: A systematic review and meta-analysis of cohort studies

BACKGROUND & AIMS

Increasingly populations are both overweight/obese and consume alcohol. The risk of liver disease from the combination of these factors is unclear. We performed a systematic review and meta-analysis to address this important gap in evidence. Protocol registered with PROSPERO(CRD42016046508).

METHODS

We performed electronic searches of Ovid Medline, Embase Classic + Embase, until 17th June 2020 for cohort studies of adults without pre-existing liver disease. Primary outcome was morbidity/mortality from chronic liver disease. Exposures were alcohol consumption categorised as within or above UK recommended limits (14 units/112 g per week) and BMI categorised as normal, overweight or obese. Non-drinkers were excluded. A Poisson regression log-linear model was used to test for statistical interaction between alcohol and BMI and to conduct a one-stage meta-analysis.

RESULTS

Searches identified 3129 studies-16 were eligible. Of these, nine cohorts (1,121,514 participants) had data available and were included in the analysis. The Poisson model showed no significant statistical interaction between alcohol consumption and BMI on the risk of chronic liver disease. Compared to normal weight participants drinking alcohol within UK recommended limits, relative risk of chronic liver disease in overweight participants drinking above limits was 3.32 (95% CI 2.88 to 3.83) and relative risk in obese participants drinking above limits was 5.39 (95% CI 4.62 to 6.29).

CONCLUSIONS

This meta-analysis demonstrated a significantly increased risk of chronic liver disease in participants who were both overweight/obese and consumed alcohol above UK recommended limits. This evidence should inform advice given to patients and risk stratification by healthcare professionals.

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.

A two-hit model of alcoholic liver disease that exhibits rapid, severe fibrosis

Alcoholic liver disease (ALD) is responsible for an average of 50.4% and 44.2%of liver disease deaths among males and females respectively. Driven by alcohol misuse, ALD is often reversible by cessation of consumption. However, abstinence programs can have limited success at curtailing abuse, and the loss of life. ALD, therefore, remains a significant clinical challenge. There is a need for effective treatments that prevent or reverse alcohol-induced liver damage to complement or supplant behavioral interventions. Metabolic syndrome, which is disproportionally prevalent in ALD patients, accelerates the progression of ALD and increases liver disease mortality. Current rodent models of ALD unfortunately do not account for the contribution of the western diet to ALD pathology. To address this, we have developed a rodent model of ALD that integrates the impact of the western diet and alcohol; the WASH-diet model. We show here that the WASH diet, either chronically or in small time-restricted bouts, accelerated ALD pathology with severe steatohepatitis, elevated inflammation and increased fibrosis compared to mice receiving chronic alcohol alone. We also validated our WASH-diet model as an in vivo system for testing the efficacy of experimental ALD treatments. The efficacy of the inverse-agonist SR9238, previously shown to inhibit both non-alcohol and alcohol-induced steatohepatitis progression, was conserved in our WASH-diet model. These findings suggested that the WASH-diet may be useful for in vivo pre-clinical assessment of novel therapies.

Increased Prevalence of Obesity and Metabolic Syndrome in Patients with Alcoholic Fatty Liver Disease

BACKGROUND AND AIMS

Obesity and diabetes are risk factors for advanced alcoholic liver disease, and both are components of the metabolic syndrome. We aimed to assess the prevalence of metabolic syndrome and its components in a contemporary US cohort of adults with alcoholic liver disease and compare it to a historic cohort to assess changes over time.

METHOD

Individuals 18 years or older who participated in the National Health and Nutrition Examination Survey during 2009-2014 and 1999-2001 were used as the contemporary and historic cohort, respectively. Alcoholic liver disease was defined as excessive alcohol consumption (men: ≥ 3 drinks/day; women: ≥ 2 drinks/day) and elevated alanine aminotransferase. Metabolic syndrome definition was based on the updated International Diabetes Federation criteria. Data are presented as mean ± standard error or unweighted frequency. A logistic regression analysis was performed to assess differences in metabolic syndrome components between the two period cohorts while adjusting for central obesity.

RESULTS

The mean age for our contemporary cohort was 41.9, 66.1% being male. Central obesity was present in 66.3%, type 2 diabetes in 18.7%, low high-density lipoprotein in 28.3%, hypertriglyceridemia in 44.8%, and hypertension in 54.7%. 36.9% met the criteria for metabolic syndrome. Compared to the historic cohort, patients in the contemporary cohort were more likely to have central obesity (50% vs. 66%, p = 0.002), metabolic syndrome (26% vs. 37%, p = 0.044), and type 2 diabetes (12% vs. 19%, p = 0.099).

CONCLUSIONS

Prevalence of both obesity and metabolic syndrome is increasing in alcoholic liver disease patients. Further studies are required to investigate effective interventions to avoid disease progression in these high-risk patients.

Corneal nerve loss in children with type 1 diabetes mellitus without retinopathy or microalbuminuria

Aims/Introduction

Corneal confocal microscopy is a rapid, non‐invasive ophthalmic technique to identify subclinical neuropathy. The aim of this study was to quantify corneal nerve morphology in children with type 1 diabetes mellitus compared with age‐matched healthy controls using corneal confocal microscopy.

Materials and Methods

A total of 20 participants with type 1 diabetes mellitus (age 14 ± 2 years, diabetes duration 4.08 ± 2.91 years, glycated hemoglobin 9.3 ± 2.1%) without retinopathy or microalbuminuria and 20 healthy controls were recruited from outpatient clinics. Corneal confocal microscopy was undertaken, and corneal nerve fiber density (n/mm²), corneal nerve branch density (n/mm²), corneal nerve fiber length (mm/mm²), corneal nerve fiber tortuosity and inferior whorl length (mm/mm²) were quantified manually.

Results

Corneal nerve fiber density (22.73 ± 8.84 vs 32.92 ± 8.59; P < 0.001), corneal nerve branch density (26.19 ± 14.64 vs 47.34 ± 20.01; P < 0.001), corneal nerve fiber length (13.26 ± 4.06 vs 19.52 ± 4.54; P < 0.001) and inferior whorl length (15.50 ± 5.48 vs 23.42 ± 3.94; P < 0.0001) were significantly lower, whereas corneal nerve fiber tortuosity (14.88 ± 5.28 vs 13.52 ± 3.01; P = 0.323) did not differ between children with type 1 diabetes mellitus and controls. Glycated hemoglobin correlated with corneal nerve fiber tortuosity (P < 0.006) and aspartate aminotransferase correlated with corneal nerve fiber density (P = 0.039), corneal nerve branch density (P = 0.003) and corneal nerve fiber length (P = 0.037).

Conclusion

Corneal confocal microscopy identifies significant subclinical corneal nerve loss, especially in the inferior whorl of children with type 1 diabetes mellitus without retinopathy or microalbuminuria.

Visceral Adipose Tissue Index and Hepatocellular Carcinoma Are Independent Predictors of Outcome in Patients with Cirrhosis Having Endoscopic Treatment for Esophageal Varices

BACKGROUND

The relationship between the amount of adipose tissue and advanced-stage liver cirrhosis with esophageal varices (EV) is unknown. We aimed to reveal the prognostic significance of adipose tissues in patients with liver cirrhosis.

METHODS

We enrolled 87 patients with EV who received initial endoscopic treatment and underwent scheduled treatments in our hospital. Computed tomography (CT) images were obtained of a 5-mm slice at the umbilical level. We evaluated the effect of mortality based on the visceral adipose tissue index (VATI), subcutaneous adipose tissue index (SATI), and visceral to subcutaneous adipose tissue ratio (VSR).

RESULTS

Cox hazard multivariate analysis showed that the presence of hepatocellular carcinoma (HCC; hazard ratio [HR]: 4.650, 95% confidence interval [CI]: 1.750-12.353, p = 0.002), γ-GTP (HR: 1.003, 95% CI: 1.001-1.006, p = 0.026), and VATI (HR: 1.057, 95% CI: 1.030-1.085, p < 0.001) significantly affected mortality. Cox hazard multivariate analysis for liver-related death was also significantly affected by HCC (HR: 1.057, 95% CI: 1.030-1.085, p < 0.001) and VATI (HR: 1.052, 95% CI: 1.019-1.086, p = 0.002). The difference between the Child-Pugh scores 12 months after treatment and that during initial treatment were significantly positively correlated with VATI (r = 0.326, p = 0.027). Patients with high VATI had a significantly higher frequency of HCC after EV treatment by Kaplan-Meier analysis (p = 0.044).

CONCLUSION

Our findings suggest that VATI measured by CT could significantly predict mortality in cirrhosis patients through decreasing liver function and increasing HCC frequency, and appropriately controlling VATI could improve their prognosis.

Association of body mass index with serum alanine aminotransferase in Chinese adolescents: a school-based cross-sectional study

BACKGROUND

Numerous studies have consistently demonstrated that high body mass index (BMI) is related to elevated serum alanine aminotransferase (ALT) among adults, but little is known about the association regarding adolescents, especially in China. In this study, we aimed to investigate the association between BMI and ALT activity among Chinese adolescents.

METHODS

A school-based cross-sectional study was performed among nine high schools in Shenzhen, China between February 2017 and June 2018. A generalized linear-regression model adjusting for age and gender was conducted, and bivariate correlation analysis between ALT and BMI was also performed.

RESULTS

A total of 7,271 adolescents aged from 9 years to 17 years were enrolled. Height, weight, BMI, and ALT were higher among boys than among girls (all P < 0.001). The mean (standard deviation) of serum ALT levels was 14.26 (14.77) U/L. In the entire BMI range, the BMI-ALT correlation was stronger for boys (Spearman's r = 0.396, P < 0.001) and adolescents of 14 years-17 years (r = 0.356, P < 0.001) than for girls (r = 0.203, P < 0.001) and adolescents of 9 years-13 years (r = 0.221, P < 0.001), respectively. Serum ALT increased rapidly and followed a linear pattern from the point of BMI ≥20.5 kg/m², and each increase of 1 kg/m² in BMI range above 20.5 kg/m² was averagely correlated with an increase of 2.71 U/L in ALT levels (P < 0.001).

CONCLUSIONS

We found a significant BMI-ALT relationship. BMI at 20.5 kg/m² may be a cut-off for evaluating serum ALT. BMIs ≥27.1 kg/m² for boys and ≥24.9 kg/m² for girls were linked to an elevated ALT activity for Shenzhen adolescents.

Addition of trans fat and alcohol has divergent effects on atherogenic diet-induced liver injury in rodent models of steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) and alcoholic liver disease (ALD) are common causes of chronic liver disease. The overlap between ALD and NAFLD suggests the existence of metabolic steatohepatitis. Development of in vivo models that reflect various aspects of human steatohepatitis is essential for drug discovery. We aimed to characterize several models of steatohepatitis (SH) and to investigate whether the pathology could be modulated. Sprague-Dawley rats were fed a high-fat diet (HFD) for 9 wk, followed by either a high-fat, high-cholesterol and cholate diet (HFC) or a HFC diet containing 13% trans fat (HFC-TF). A subset received 15% ethanol-water twice a week for 12 wk. Serum triglycerides, cholesterol, LDL, HDL, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and rodent NH₂-terminal propeptide of type III collagen (rPRO-C3) were assessed. The liver was weighed and evaluated using modified Nonalcoholic Steatohepatitis Clinical Research Network histological score system criteria. All diets induced hepatomegaly, but only HFC-TF increased the size of visceral adipose tissue. Trans fat augmented HFC-induced dyslipidemia, and cholesterol was higher and HDL was lower in the HFC-TF groups. Alcohol lowered triglycerides in both dietary groups. HFC elevated ALT and AST, which were lowered by trans fat. All diets induced histological SH, addition of trans fat induced more steatosis but less inflammation. Inclusion of alcohol augmented the HFC-induced inflammation. All diets induced mild fibrosis. Inclusion of trans fat and alcohol significantly increased rPRO-C3. The addition of trans fat reduced the HFC-induced inflammation but augmented steatosis and dyslipidemia. Inclusion of alcohol induced a more inflammatory and fibrogenic phenotype.NEW & NOTEWORTHY Alcoholic liver disease and nonalcoholic liver disease share significant overlap, which suggests the existence of metabolic steatohepatitis. Trans fat has been implicated in steatohepatitis development. Here, we show that the addition of trans fat to an atherogenic diet results in a more steatotic but less inflammatory phenotype, whereas the addition of alcohol to an atherogenic diet augments the inflammatory and fibrogenic properties of the diet.

Profiles of advanced hepatic fibrosis evaluated by FIB-4 index and shear wave elastography in health checkup examinees

AIM

Advanced hepatic fibrosis is seen in individuals with potential hepatocellular carcinoma and cardiovascular disease. Hepatic fibrosis can be assessed using a combination of the FIB-4 index and imaging modalities, including shear wave elastography. We aimed to investigate the prevalence of advanced fibrosis in the general population and the profiles associated with advanced fibrosis using a data-mining analysis.

METHODS

We enrolled 1155 health checkup examinees (median age 53 years, 685 women, 470 male). Advanced fibrosis was defined by FIB-4 index ≥1.3 and liver stiffness ≥8.07 kPa using shear wave elastography. Participants were classified as normal-mild fibrosis (n = 1035) or advanced fibrosis (n = 120). Factors associated with advanced fibrosis were analyzed by logistic regression and decision-tree analyses.

RESULTS

Advanced fibrosis was observed in 10.4% of participants (120/1155). In the logistic regression analysis, independent factors for advanced fibrosis were age (≥75 years; OR 2.12, 95% CI 1.021-4.415; P = 0.0419) and the presence of metabolic syndrome (OR 2.51, 95% CI 1.416-4.462; P = 0.0017). The decision-tree analysis showed two profiles associated with advanced fibrosis: profile 1 - individuals aged ≥65 years with metabolic syndrome and mild-to-moderate alcohol consumption (prevalence of advanced fibrosis 73.3%); and profile 2 - individuals without metabolic syndrome, aged ≥75 years, with no exercise habit (prevalence of advanced fibrosis 56.3%).

CONCLUSIONS

Advanced fibrosis was observed in 10.4% of health checkup examinees. Furthermore, we showed that aging, metabolic syndrome with mild-to-moderate alcohol consumption, and physical inactivity were associated with advanced fibrosis. Thus, prevention of metabolic syndrome and alcohol withdrawal, as well as exercise habits, might inhibit the progression of hepatic fibrosis.

Alcohol-related liver disease. Clinical practice guidelines. Consensus document sponsored by AEEH

Alcohol-related liver disease (ARLD) is the most prevalent cause of advanced liver disease and liver cirrhosis in Europe, including Spain. According to the World Health Organization the fraction of liver cirrhosis attributable to alcohol use in Spain is 73.8% among men and 56.3% among women. ARLD includes various stages such as steatohepatitis, cirrhosis and hepatocellular cancer. In addition, patients with underlying ARLD and heavy alcohol intake may develop alcoholic hepatitis, which is associated with high mortality. To date, the only effective treatment to treat ARLD is prolonged withdrawal. There are no specific treatments, and the only treatment that increases life expectancy in alcoholic hepatitis is prednisolone. For patients with alcoholic hepatitis who do not respond to treatment, some centres offer the possibility of an early transplant. These clinical practice guidelines aim to propose recommendations on ARLD taking into account their relevance as a cause of advanced chronic liver disease and liver cirrhosis in our setting. This paper aims to answer the key questions for the clinical practice of Gastroenterology, Hepatology, as well as Internal Medicine and Primary Health Centres, making the most up-to-date information regarding the management and treatment of ARLD available to health professionals. These guidelines provide evidence-based recommendations for the clinical management of this disease.

Characterization of patients with both alcoholic and nonalcoholic fatty liver disease in a large United States cohort

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome (MetS) and is characterized by steatosis in the absence of significant alcohol consumption. However, MetS and significant alcohol intake coexist in certain individuals which may lead to the development of BAFLD.

AIM

To assess the clinical characteristics of patients with both alcoholic and NAFLD (BAFLD) in a large cohort in the United States.

METHODS

Adults from the National Health and Nutrition Examination Survey between 2003-2014 were included. NAFLD was diagnosed based on elevated alanine aminotransferase (ALT) and being overweight or obese in the absence of other liver diseases. BAFLD patients met the criteria for NAFLD but also had either MetS or type 2 diabetes and consumed excessive amounts of alcohol. Univariable and multivariable analysis were performed to assess differences between NAFLD and BAFLD and to compare severity based on a validated fibrosis score (FIB4 index).

RESULTS

The prevalence of NAFLD was at 25.9% (95%CI; 25.1-26.8) and that of BAFLD was 0.84% (0.67, 1.02) which corresponds to an estimated 1.24 million Americans affected by BAFLD. Compared to NAFLD, patients with BAFLD were more likely to be male, smokers, have higher ALT, aspartate aminotransferase, triglycerides, and lower platelets; P < 0.01 for all. More importantly, after adjusting for MetS components, BAFLD patients were significantly more likely to have advanced fibrosis [adjusted OR (95%CI) based on FIB4 index > 2.67 was 3.2 (1.4, 7.0), P = 0.004].

CONCLUSION

A significant percentage of the American general population is afflicted by BAFLD and these patients tend to have more advanced liver fibrosis.

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.

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.

Laboratory test based assessment of WHO alcohol risk drinking levels

Low-risk thresholds for alcohol use differ across various national guidelines. To assess the novel WHO risk drinking levels in light of alcohol-sensitive common laboratory tests, we analysed biomarkers of liver status, inflammation and lipid profiles from a population-based survey of individuals classified to abstainers and different WHO risk drinking levels defined in terms of mean alcohol consumption per day. The study included 22,327 participants aged 25-74 years from the National FINRISK Study. Data on alcohol use, health status, diet, body weight and lifestyle (smoking, coffee consumption and physical activity) were recorded from structured interviews. Alcohol data from self-reports covering the past 12 months were used to categorize the participants into subgroups of abstainers and WHO risk drinking categories representing low, moderate, high and very high risk drinkers. Serum liver enzymes (GGT, ALT), C-reactive protein (CRP) and lipid profiles were measured using standard laboratory techniques. Alcohol risk category was roughly linearly related with the occurrence of elevated values for GGT, ALT and CRP. Alcohol drinking also significantly influenced the incidence of abnormalities in serum lipids. Significantly higher odds for abnormal GGT, ALT and altered lipid profiles remained in alcohol drinkers even after adjustment for age, waist circumference, physical inactivity, smoking and coffee consumption. A more systematic use of laboratory tests during treatment of individuals classified to WHO risk drinking categories may improve the assessment of alcohol-related health risks. Follow-ups of biomarker responses may also prove to be useful in health interventions aimed at reducing alcohol consumption.

Alcoholic liver disease: A current molecular and clinical perspective

Heavy alcohol use is the cause of alcoholic liver disease (ALD). The ALD spectrum ranges from alcoholic steatosis to steatohepatitis, fibrosis, and cirrhosis. In Western countries, approximately 50% of cirrhosis-related deaths are due to alcohol use. While alcoholic cirrhosis is no longer considered a completely irreversible condition, no effective anti-fibrotic therapies are currently available. Another significant clinical aspect of ALD is alcoholic hepatitis (AH). AH is an acute inflammatory condition that is often comorbid with cirrhosis, and severe AH has a high mortality rate. Therapeutic options for ALD are limited. The established treatment for AH is corticosteroids, which improve short-term survival but do not affect long-term survival. Liver transplantation is a curative treatment option for alcoholic cirrhosis and AH, but patients must abstain from alcohol use for 6 months to qualify. Additional effective therapies are needed. The molecular mechanisms underlying ALD are complex and have not been fully elucidated. Various molecules, signaling pathways, and crosstalk between multiple hepatic and extrahepatic cells contribute to ALD progression. This review highlights established and emerging concepts in ALD clinicopathology, their underlying molecular mechanisms, and current and future ALD treatment options.

PNPLA3 Association with Alcoholic Liver Disease in a Cohort of Heavy Drinkers

Aims

Prior studies have established variation at the PNPLA3 gene to be associated with a risk of developing alcoholic liver disease (ALD). We attempt to replicate this finding and other potential genetic variations previously associated with ALD utilizing a case-control design in a cohort of subjects with alcohol use disorders.

Short summary

This case-control study performed in a US clinical sample of heavy drinkers, replicates the previously reported association between ALD and rs738409 polymorphism in the PNPLA3 gene in heavy drinkers. This association persisted after accounting for the subject's diabetes status.

Methods

Patients of European ancestry with a history of ALD were identified (n = 169). Controls consisted of patients without ALD who were from the same cohorts and were ≥ 30 years of age, had lifetime total years drinking ≥20 and lifetime maximum drinks per day ≥12 (n = 259). Patients were genotyped for 40 candidate single nucleotide polymorphisms (SNPs) selected for the purpose of testing their association with ALD. The association of each SNP with ALD was tested using a logistic regression model, assuming log-additive allele effects. Bonferroni correction was applied and multivariable logistic regression models were used to account for relevant covariates.

Results

Age, sex, and body mass index (BMI) distributions were similar between cases and controls. Diabetes was more prevalent in the ALD cases. Three SNPs were associated with ALD at the nominal significance level (rs738409 in PNPLA3, P = 0.00029; rs3741559 in AQP2, P = 0.0185; rs4290029 in NVL, P = 0.0192); only PNPLA3 rs738409 SNP was significant at the Bonferroni-corrected P-value threshold of 0.00125. Association results remained significant after adjustment for diabetes status.

Conclusion

Our case-control study confirmed that PNPLA3 rs738409 SNP is associated with ALD. This is an important replication in a US clinical sample with control subjects who had long histories of alcohol consumption.

Alcoholic liver disease

Alcoholic liver disease (ALD) is the most prevalent type of chronic liver disease worldwide. ALD can progress from alcoholic fatty liver (AFL) to alcoholic steatohepatitis (ASH), which is characterized by hepatic inflammation. Chronic ASH can eventually lead to fibrosis and cirrhosis and in some cases hepatocellular cancer (HCC). In addition, severe ASH (with or without cirrhosis) can lead to alcoholic hepatitis, which is an acute clinical presentation of ALD that is associated with liver failure and high mortality. Most individuals consuming >40 g of alcohol per day develop AFL; however, only a subset of individuals will develop more advanced disease. Genetic, epigenetic and non-genetic factors might explain the considerable interindividual variation in ALD phenotype. The pathogenesis of ALD includes hepatic steatosis, oxidative stress, acetaldehyde-mediated toxicity and cytokine and chemokine-induced inflammation. Diagnosis of ALD involves assessing patients for alcohol use disorder and signs of advanced liver disease. The degree of AFL and liver fibrosis can be determined by ultrasonography, transient elastography, MRI, measurement of serum biomarkers and liver biopsy histology. Alcohol abstinence achieved by psychosomatic intervention is the best treatment for all stages of ALD. In the case of advanced disease such as cirrhosis or HCC, liver transplantation may be required. Thus, new therapies are urgently needed.

Interaction between alcohol consumption and metabolic syndrome in predicting severe liver disease in the general population

The metabolic syndrome and alcohol risk use are both associated with a high prevalence of hepatic steatosis, but only a minority develop liver failure or liver cancer. Few general population studies have analyzed metabolic predictors of such severe liver complications. We studied which metabolic factors best predict severe liver complications, stratified by alcohol consumption, in 6732 individuals without baseline liver disease who participated in the Finnish population-based Health 2000 Study (2000-2001), a nationally representative cohort. Follow-up data from national registers until 2013 were analyzed for liver-related admissions, mortality, and liver cancer. Baseline alcohol use and metabolic factors were analyzed by backward stepwise Cox regression analysis. Eighty-four subjects experienced a severe liver event during follow-up. In the final multivariate model, factors predictive of liver events were age (hazard ratio [HR], 1.02; 95% confidence interval [CI], 1.004-1.04), sex (women: HR, 0.55; 95% CI, 0.34-0.91), alcohol use (HR, 1.002; 95% CI, 1.001-1.002), diabetes (HR, 2.73; 95% CI, 1.55-4.81), low-density lipoprotein (LDL) cholesterol (HR, 0.74; 95% CI, 0.58-0.93), and homeostasis model assessment of insulin resistance (HOMA-IR) (HR, 1.01; 95% CI, 1.004-1.02). Among alcohol risk users (≥210 g/week for men, ≥ 140 g/week for women), diabetes (HR, 6.79; 95% CI, 3.18-14.5) was the only significant predictor. Among nonrisk drinkers, age, alcohol use, smoking, waist circumference, low LDL cholesterol and HOMA-IR were significant independent predictors. The total-to-LDL cholesterol ratio and waist circumference-to-body mass index ratio emerged as additional independent predictors.

CONCLUSION

Multiple components of the metabolic syndrome independently affected the risk for severe liver disease. Alcohol was significant even when average alcohol consumption was within the limits currently defining nonalcoholic fatty liver disease. (Hepatology 2018;67:2141-2149).

The bidirectional impacts of alcohol consumption and the metabolic syndrome: Cofactors for progressive fatty liver disease

Current medical practice artificially dichotomises a diagnosis of fatty liver disease into one of two common forms: alcoholic liver disease (ALD) and non-alcoholic fatty liver disease (NAFLD). Together, these account for the majority of chronic liver diseases worldwide. In recent years, there has been a dramatic increase in the prevalence of obesity and metabolic syndrome within the general population. These factors now coexist with alcohol consumption in a substantial proportion of the population. Each exposure sensitises the liver to the injurious effects of the other; an interaction that drives and potentially accelerates the genesis of liver disease. We review the epidemiological evidence and scientific literature that considers how alcohol consumption interacts with components of the metabolic syndrome to exert synergistic or supra-additive effects on the development and progression of liver disease, before discussing how these interactions may be addressed in clinical practice.

Rodent Models of Alcoholic Liver Disease: Role of Binge Ethanol Administration

Both chronic and acute (binge) alcohol drinking are important health and economic concerns worldwide and prominent risk factors for the development of alcoholic liver disease (ALD). There are no FDA-approved medications to prevent or to treat any stage of ALD. Therefore, discovery of novel therapeutic strategies remains a critical need for patients with ALD. Relevant experimental animal models that simulate human drinking patterns and mimic the spectrum and severity of alcohol-induced liver pathology in humans are critical to our ability to identify new mechanisms and therapeutic targets. There are several animal models currently in use, including the most widely utilized chronic ad libitum ethanol (EtOH) feeding (Lieber–DeCarli liquid diet model), chronic intragastric EtOH administration (Tsukamoto–French model), and chronic-plus-binge EtOH challenge (Bin Gao—National Institute on Alcohol Abuse and Alcoholism (NIAAA) model). This review provides an overview of recent advances in rodent models of binge EtOH administration which help to recapitulate different features and etiologies of progressive ALD. These models include EtOH binge alone, and EtOH binge coupled with chronic EtOH intake, a high fat diet, or endotoxin challenge. We analyze the strengths, limitations, and translational relevance of these models, as well as summarize the liver injury outcomes and mechanistic insights. We further discuss the application(s) of binge EtOH models in examining alcohol-induced multi-organ pathology, sex- and age-related differences, as well as circadian rhythm disruption.

Where should the safe limits of alcohol consumption stand in light of liver enzyme abnormalities in alcohol consumers?

Objectives

To estimate the prevalence and risk factors for abnormal liver enzymes in a large age- and gender stratified population-based sample of apparently healthy individuals with or without alcohol consumption and other health-related risk factors (adiposity, physical inactivity, smoking).

Methods

Data on alcohol use, smoking, diet and physical activity were recorded using structured questionnaires from 13,976 subjects (6513 men, 7463 women, aged 25–74 years) in the national FINRISK studies. Alcohol data was used to categorize the participants into abstainers, light drinkers, moderate drinkers and heavy drinkers. Serum gamma-glutamyltransferase (GGT) and alanine aminotransferase (ALT) activities were measured using standard kinetic methods.

Results

Male light drinkers, moderate drinkers and heavy drinkers showed significantly higher relative risks of abnormal GGT than abstainers: 1.37 (95% confidence interval 1.11 to 1.71, p < 0.01), 2.72 (2.08 to 3.56, p < 0.0005), and 6.10 (4.55 to 7.17, p < 0.0005), respectively. Corresponding values for women were 1.22 (0.99 to 1.51, p = 0.065), 1.90 (1.44 to 2.51, p < 0.0005), and 5.91 (3.80 to 9.17, p < 0.0005). Estimated threshold doses for a significant GGT elevation was 14 standard weekly alcohol doses for men and 7 for women. Excess body weight and age over 40 years modulated the thresholds towards smaller quantities of alcohol. The risk of abnormal GGT was also significantly influenced by physical inactivity and smoking. The relative risks of abnormal ALT activities were increased in male heavy drinkers, especially in those presenting with adiposity and sedentary lifestyle.

Conclusions

Alcohol use markedly increases the risk for abnormal liver enzyme activities in those presenting with age over 40 years, obesity, smoking or sedentary lifestyle. The data should be considered in public health recommendations and in the definitions of safe limits of alcohol use.

Animal Models of Alcoholic Liver Disease: Pathogenesis and Clinical Relevance

Alcoholic liver disease (ALD), a leading cause of chronic liver injury worldwide, comprises a range of disorders including simple steatosis, steatohepatitis, cirrhosis, and hepatocellular carcinoma. Over the last five decades, many animal models for the study of ALD pathogenesis have been developed. Recently, a chronic-plus-binge ethanol feeding model was reported. This model induces significant steatosis, hepatic neutrophil infiltration, and liver injury. A clinically relevant model of high-fat diet feeding plus binge ethanol was also developed, which highlights the risk of excessive binge drinking in obese/overweight individuals. All of these models recapitulate some features of the different stages of ALD and have been widely used by many investigators to study the pathogenesis of ALD and to test for therapeutic drugs/components. However, these models are somewhat variable, depending on mouse genetic background, ethanol dose, and animal facility environment. This review focuses on these models and discusses these variations and some methods to improve the feeding protocol. The pathogenesis, clinical relevance, and translational studies of these models are also discussed.

Inflammation is independent of steatosis in a murine model of steatohepatitis

Obesity and alcohol consumption synergistically promote steatohepatitis, and neutrophil infiltration is believed to be associated with steatosis. However, the underlying mechanisms remain obscure. Peroxisome proliferator-activated receptor gamma (PPARγ) plays a complex role in lipid metabolism and inflammation; therefore, the purpose of this study was to dissect its role in regulating steatosis and neutrophil infiltration in a clinically relevant mouse steatohepatitis model of 3-month high-fat diet (HFD) feeding plus a binge of ethanol (HFD-plus-binge ethanol). Hepatocyte-specific Pparg disruption reduced liver steatosis but surprisingly increased hepatic neutrophil infiltration after HFD-plus-binge ethanol. Knockout or knockdown of the PPARγ target gene, fat-specific protein 27, reduced steatosis without affecting neutrophil infiltration in this model. Moreover, hepatocyte-specific deletion of the Pparg gene, but not the fat-specific protein 27 gene, markedly up-regulated hepatic levels of the gene for chemokine (C-X-C motif) ligand 1 (Cxcl1, a chemokine for neutrophil infiltration) in HFD-plus-binge ethanol-fed mice. In vitro, deletion of the Pparg gene also highly augmented palmitic acid or tumor necrosis factor alpha induction of Cxcl1 in mouse hepatocytes. In contrast, activation of PPARγ with a PPARγ agonist attenuated Cxcl1 expression in hepatocytes. Palmitic acid also up-regulated interleukin-8 (a key chemokine for human neutrophil recruitment) expression in human hepatocytes, which was attenuated and enhanced by cotreatment with a PPARγ agonist and antagonist, respectively. Finally, acute ethanol binge markedly attenuated HFD-induced hepatic PPARγ activation, which contributed to the up-regulation of hepatic Cxcl1 expression post-HFD-plus-binge ethanol.

CONCLUSION

Hepatic PPARγ plays an opposing role in controlling steatosis and neutrophil infiltration, leading to dissociation between steatosis and inflammation; acute ethanol gavage attenuates hepatic PPARγ activation and subsequently up-regulates hepatic CXCL1/interleukin-8 expression, thereby exacerbating hepatic neutrophil infiltration. (Hepatology 2017;66:108-123).

Risk of chronic liver disease in post-menopausal women due to body mass index, alcohol and their interaction: a prospective nested cohort study within the United Kingdom Collaborative Trial of Ovarian Cancer Screening (UKCTOCS)

Background

We investigated the risk of chronic liver disease (CLD) due to alcohol consumption and body mass index (BMI) and the effects of their interaction in a prospective cohort study of women recruited to the UKCTOCS trial.

Methods

95,126 post-menopausal women without documented CLD were stratified into 12 groups defined by combinations of BMI (normal, overweight, obese) and alcohol consumption (none, <1–15, 16–20 and ≥21 units/week), and followed for an average of 5.1 years. Hazard ratios (HR) were calculated for incident liver-related events (LRE).

Results

First LREs were reported in 325 (0.34%) participants. Compared to women with normal BMI, HR = 1.44 (95% CI; 1.10–1.87) in the overweight group and HR = 2.25 (95% CI; 1.70–2.97) in the obese group, adjusted for alcohol and potential confounders. Compared to those abstinent from alcohol, HR = 0.70 (95% CI; 0.55–0.88) for <1–15 units/week, 0.93 (95% CI; 0.50–1.73) for 16–20 units/week and 1.82 (95% CI; 0.97–3.39) for ≥21 units/week adjusted for BMI and potential confounders. Compared to women with normal BMI drinking no alcohol, HR for LRE in obese women consuming ≥21 units/week was 2.86 (95% CI; 0.67–12.42), 1.58 (95% CI; 0.96–2.61) for obese women drinking <1–15 units/week and 1.93 (95% CI; 0.66–5.62) in those with normal BMI consuming ≥21 units/week after adjustment for potential confounders. We found no significant interaction between BMI and alcohol.

Conclusion

High BMI and alcohol consumption and abstinence are risk factors for CLD in post-menopausal women. However, BMI and alcohol do not demonstrate significant interaction in this group.

Trial registration

UKCTOCS is registered as an International Standard Randomised Controlled Trial, number ISRCTN22488978. Registered 06/04/2000.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-017-4518-y) contains supplementary material, which is available to authorized users.