Adipocyte retinoic acid receptor α prevents obesity and steatohepatitis by regulating energy expenditure and lipogenesis.

OBJECTIVE: The adipose tissue-liver axis is a major regulator of the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Retinoic acid signaling plays an important role in development and metabolism. However, little is known about the role of adipose retinoic acid signaling in the development of obesity-associated NAFLD. In this work, the aim was to investigate whether and how retinoic acid receptor alpha (RARα) regulated the development of obesity and NAFLD. METHODS: RARα expression in adipose tissue of db/db or ob/ob mice was determined. Rarαfl/fl mice and adipocyte-specific Rarα-/- (RarαAdi-/- ) mice were fed a chow diet for 1 year or high-fat diet (HFD) for 20 weeks. Primary adipocytes and primary hepatocytes were co-cultured. Metabolic regulation and inflammatory response were characterized. RESULTS: RARα expression was reduced in adipose tissue of db/db or ob/ob mice. RarαAdi-/- mice had increased obesity and steatohepatitis (NASH) when fed a chow diet or HFD. Loss of adipocyte RARα induced lipogenesis and inflammation in adipose tissue and the liver and reduced thermogenesis. In the co-culture studies, loss of RARα in adipocytes induced inflammatory and lipogenic programs in hepatocytes. CONCLUSIONS: The data demonstrate that RARα in adipocytes prevents obesity and NASH via inhibiting lipogenesis and inflammation and inducing energy expenditure.

Global Epidemiology of Cirrhosis: Changing Etiological Basis and Comparable Burden of Nonalcoholic Steatohepatitis between Males and Females.

INTRODUCTION: The etiology of liver diseases has changed significantly, but its impact on the comparative burden of cirrhosis between males and females is unclear. We estimated sex differences in the burden of cirrhosis across 204 countries and territories from 2010 to 2019. METHODS: We analyzed temporal trends in the burden of cirrhosis using the methodology framework of the 2019 Global Burden of Disease study. We estimated annual frequencies and age-standardized rates (ASRs) of cirrhosis incidence, death, and disability-adjusted life-years (DALYs) by sex, region, country, and etiology. RESULTS: In 2019, the frequency of incident cases, deaths, and DALYs due to cirrhosis was 1,206,125, 969,068, and 31,781,079 in males versus 845,429, 502,944, and 14,408,336 in females, respectively. From 2010 to 2019, the frequency of cirrhosis deaths increased by 9% in males and 12% in females. Incidence ASRs remained stable in males but increased in females, while death ASRs declined in both. Death ASRs for both sexes declined in all regions, except in the Americas where they remained stable. In 2019, alcohol was the leading cause of cirrhosis deaths in males, and hepatitis C in females. Death ASRs declined for all etiologies in both sexes, except in nonalcoholic steatohepatitis (NASH). The ratio of female-to-male incidence ASRs in 2019 was lowest in alcohol(0.5), and highest in NASH(1.3), while the ratio of female-to-male death ASRs was lowest in alcohol(0.3) and highest in NASH(0.8). CONCLUSION: The global burden of cirrhosis is higher in males. However, incidence and death ASRs from NASH cirrhosis in females are comparable to that of males.

Assessment of Areca Nut Bioactivities in Western Diet-Induced Mice NAFLD Model.

The areca nut is often consumed as a chewing food in the Asian region. Our previous study revealed that the areca nut is rich in polyphenols with high antioxidant activity. In this study, we further assessed the effects and molecular mechanisms of the areca nut and its major ingredients on a Western diet-induced mice dyslipidemia model. Male C57BL/6N mice were divided into five groups and fed with a normal diet (ND), Western diet (WD), WD with areca nut extracts (ANE), areca nut polyphenols (ANP), and arecoline (ARE) for 12 weeks. The results revealed that ANP significantly reduced WD-induced body weight, liver weight, epididymal fat, and liver total lipid. Serum biomarkers showed that ANP ameliorated WD-enhanced total cholesterol and non-high-density lipoprotein (non-HDL). Moreover, analysis of cellular signaling pathways revealed that sterol regulatory element-binding protein 2 (SREBP2) and enzyme 3-hydroxy-3-methylglutaryld coenzyme A reductase (HMGCR) were significantly downregulated by ANP. The results of gut microbiota analysis revealed that ANP increased the abundance of beneficial bacterium Akkermansias and decreased the abundance of the pathogenic bacterium Ruminococcus while ARE shown the opposite result to ANP. In summary, our data indicated that areca nut polyphenol ameliorated WD-induced dyslipidemia by increasing the abundance of beneficial bacteria in the gut microbiota and reducing the expressions of SREBP2 and HMGCR while areca nut ARE inhibited this improvement potential.

Ferulic Acid Prevents Nonalcoholic Fatty Liver Disease by Promoting Fatty Acid Oxidation and Energy Expenditure in C57BL/6 Mice Fed a High-Fat Diet.

There is a consensus that ferulic acid (FA), the most prominent phenolic acid in whole grains, displays a protective effect in non-alcoholic fatty liver disease (NAFLD), though its underlying mechanism not fully elucidated. This study aimed to investigate the protective effect of FA on high-fat diet (HFD)-induced NAFLD in mice and its potential mechanism. C57BL/6 mice were divided into the control diet (CON) group, the HFD group, and the treatment (HFD+FA) group, fed with an HFD and FA (100 mg/kg/day) by oral gavage for 12 weeks. Hematoxylin and eosin (H&E) staining and Oil Red O staining were used to evaluate liver tissue pathological changes and lipid accumulation respectively. It was demonstrated that FA supplementation prevented HFD-induced NAFLD, which was evidenced by the decreased accumulation of lipid and hepatic steatosis in the HFD+FA group. Specifically, FA supplementation decreased hepatic triacylglycerol (TG) content by 33.5% (p < 0.01). Metabolic cage studies reveal that FA-treated mice have elevated energy expenditure by 11.5% during dark phases. Mechanistically, FA treatment increases the expression of rate-limiting enzymes of fatty acid oxidation and ketone body biosynthesis CPT1A, ACOX1 and HMGCS2, which are the peroxisome proliferator-activated receptors α (PPARα) targets in liver. In conclusion, FA could effectively prevent HFD-induced NAFLD possibly by activating PPARα to increase energy expenditure and decrease the accumulation of triacylglycerol in the liver.

Dietary Risks for Liver Mortality in NAFLD: Global Burden of Disease Data.

Nonalcoholic fatty liver disease (NAFLD) is a common but complex chronic liver disease, driven by environmental and genetic factors. We assessed metabolic and dietary risk factor associations with NAFLD liver mortality using the Global Burden of Disease (GBD) 2017 data. NAFLD liver deaths were calculated (per 100,000) as age-standardized rates (ASRs) from 195 countries and territories (21 GBD regions; 7 GBD superregions). Dietary risks included low intake of fruits, vegetables, legumes, whole grains, nuts/seeds, milk, fiber, calcium, seafood omega-3 fatty acids, and polyunsaturated fatty acids, and high intake of red meat, processed meat, sugar-sweetened beverages, trans fatty acids, and sodium. Metabolic risks included high low-density lipoprotein cholesterol, systolic blood pressure (BP), fasting glucose (FG), body mass index (BMI), as well as low bone mineral density and impaired kidney function (IKF). Socio-demographic index (SDI)-adjusted partial Spearman correlation coefficients and multivariable generalized linear regression models/bidirectional stepwise selection (significance level for entry, 0.2; for stay, 0.05) determined the associations. The ASR for NAFLD liver deaths was 2.3 per 100,000 (2017) and correlated with dietary risk factors (0.131, -0.010-0.267) and metabolic risk factors (SDI-adjusted = 0.225, 95% CI 0.086-0.354). High intake of sugar-sweetened beverages and red meat (0.358, 0.229-0.475; 0.162, 0.022-0.296), and low intake of nuts/seed and milk (0.154, 0.014-0.289; 0.145, 0.004-0.280) was significant for NAFLD liver deaths. Other risk factors for liver death included IKF (0.402, 0.276-0.514), increased BMI (0.353, 0.223-0.407), FG (0.248, 0.111-0.376), and BP (0.163, 0.022-0.297). High intake of trans fatty acids (2.84% increase [1.65%-4.03%]) was the largest associated risk of NAFLD liver deaths. In addition to metabolic risks, dietary risks independently drive the global burden of NAFLD-related liver mortality. Conclusion: These data provide additional support for policies to improve dietary environment for NAFLD burden reduction.

The Emerging Role of Glucagon-like Peptide-1 Receptor Agonists for the Management of NAFLD.

CONTEXT: The burden of cirrhosis from nonalcoholic fatty liver disease (NAFLD) is reaching epidemic proportions in the United States. This calls for greater awareness among endocrinologists, who often see but may miss the diagnosis in adults with obesity or type 2 diabetes mellitus (T2D) who are at the highest risk. At the same time, recent studies suggest that glucagon-like peptide-1 receptor agonists (GLP-1RAs) are beneficial vs nonalcoholic steatohepatitis (NASH) in this population. This minireview aims to assist endocrinologists to recognize the condition and recent work on the role of GLP-1RAs in NAFLD/NASH. EVIDENCE ACQUISITION: Evidence from observational studies, randomized controlled trials, and meta-analyses. EVIDENCE SYNTHESIS: Endocrinologists should lead multidisciplinary teams to implement recent consensus statements on NAFLD that call for screening and treatment of clinically significant fibrosis to prevent cirrhosis, especially in the high-risk groups (ie, people with obesity, prediabetes, or T2D). With no US Food and Drug Administration (FDA)-approved agents, weight loss is central to successful management, with pharmacological treatment options limited today to vitamin E (in people without T2D) and diabetes medications that reverse steatohepatitis, such as pioglitazone or GLP-1RA. Recently, the benefit of GLP-1RAs in NAFLD, suggested from earlier trials, has been confirmed in adults with biopsy-proven NASH. In 2021, the FDA also approved semaglutide for obesity management. CONCLUSION: A paradigm change is developing between the endocrinologist's greater awareness about their critical role to curve the epidemic of NAFLD and new clinical care pathways that include a broader use of GLP-1RAs in the management of these complex patients.

Impact of COVID-19 Pandemic on Liver Transplantation and Alcohol-Associated Liver Disease in the USA.

BACKGROUND AND AIMS: The surge in unhealthy alcohol use during the COVID-19 pandemic may have detrimental effects on the rising burden of alcohol-associated liver disease (ALD) on liver transplantation (LT) in the USA. We evaluated the effect of the pandemic on temporal trends for LT including ALD. APPROACH AND RESULTS: Using data from United Network for Organ Sharing, we analyzed wait-list outcomes in the USA through March 1, 2021. In a short-period analysis, patients listed or transplanted between June 1, 2019, and February 29, 2020, were defined as the "pre-COVID" era, and after April 1, 2020, were defined as the "COVID" era. Interrupted time-series analyses using monthly count data from 2016-2020 were constructed to evaluate the rate change for listing and LT before and during the COVID-19 pandemic. Rates for listings (P = 0.19) and LT (P = 0.14) were unchanged during the pandemic despite a significant reduction in the monthly listing rates for HCV (-21.69%, P < 0.001) and NASH (-13.18%; P < 0.001). There was a significant increase in ALD listing (+7.26%; P < 0.001) and LT (10.67%; P < 0.001) during the pandemic. In the COVID era, ALD (40.1%) accounted for more listings than those due to HCV (12.4%) and NASH (23.4%) combined. The greatest increase in ALD occurred in young adults (+33%) and patients with severe alcohol-associated hepatitis (+50%). Patients with ALD presented with a higher acuity of illness, with 30.8% of listings and 44.8% of LT having a Model for End-Stage Liver Disease-Sodium score ≥30. CONCLUSIONS: Since the start of COVID-19 pandemic, ALD has become the most common indication for listing and the fastest increasing cause for LT. Collective efforts are urgently needed to stem the rising tide of ALD on health care resources.

Nonalcoholic fatty liver disease is associated with the development of obstructive sleep apnea.

Increasing evidence suggests that obstructive sleep apnea (OSA) is a metabolic syndrome-related disease; however, the association between nonalcoholic fatty liver disease (NAFLD) and OSA is not firmly established. In this study, we investigated the relationship between NAFLD and OSA in a general population drawn from a nationwide population-based cohort. Data from the Korean National Health Insurance System between January 2009 and December 2009 were analyzed using Cox proportional hazards model. NAFLD was defined as a fatty liver index (FLI) ≥ 60 in patients without excessive alcohol consumption (who were excluded from the study). Newly diagnosed OSA during follow-up was identified using claims data. Among the 8,116,524 participants, 22.6% had an FLI score of 30-60 and 11.5% had an FLI ≥ 60. During median follow-up of 6.3 years, 45,143 cases of incident OSA occurred. In multivariable analysis, the risk of OSA was significantly higher in the higher FLI groups (adjusted hazard ratio [aHR] 1.15, 95% confidence interval [CI] 1.12-1.18 for FLI 30-60 and aHR 1.21, 95% CI 1.17-1.26 for FLI ≥ 60). These findings were consistent regardless of body mass index and presence of abdominal obesity. In conclusion, a high FLI score may help identify individuals with a high risk of OSA. Understanding the association between NAFLD and OSA may have clinical implications for risk-stratification of individuals with NAFLD.

Assessment of hepatic fatty acids during non-alcoholic steatohepatitis progression using magnetic resonance spectroscopy.

INTRODUCTION AND OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) encompasses a spectrum of liver abnormalities including steatosis, steatohepatitis, fibrosis, and cirrhosis. Liver biopsy remains the gold standard method to determine the disease stage in NAFLD but is an invasive and risky procedure. Studies have previously reported that changes in intrahepatic fatty acids (FA) composition are related to the progression of NAFLD, mainly in its early stages. The aim of this study was to characterize the liver FA composition in mice fed a Choline-deficient L-amino-defined (CDAA) diet at different stages of NAFLD using magnetic resonance spectroscopy (MRS). METHODS: We used in-vivo MRS to perform a longitudinal characterization of hepatic FA changes in NAFLD mice for 10 weeks. We validated our findings with ex-vivo MRS, gas chromatography-mass spectrometry and histology. RESULTS: In-vivo and ex-vivo results showed that livers from CDAA-fed mice exhibit a significant increase in liver FA content as well as a change in FA composition compared with control mice. After 4 weeks of CDAA diet, a decrease in polyunsaturated and an increase in monounsaturated FA were observed. These changes were associated with the appearance of early stages of steatohepatitis, confirmed by histology (NAFLD Activity Score (NAS) = 4.5). After 10 weeks of CDAA-diet, the liver FA composition remained stable while the NAS increased further to 6 showing a combination of early and late stages of steatohepatitis. CONCLUSION: Our results suggest that monitoring lipid composition in addition to total water/fat with MRS may yield additional insights that can be translated for non-invasive stratification of high-risk NAFLD patients.

Nicotinamide Protects Against Diet-Induced Body Weight Gain, Increases Energy Expenditure, and Induces White Adipose Tissue Beiging.

SCOPE: Interventions that boost NAD+ availability are of potential therapeutic interest for obesity treatment. The potential of nicotinamide (NAM), the amide form of vitamin B3 and a physiological precursor of nicotinamide adenine dinucleotide (NAD)+ , in preventing weight gain has not previously been studied in vivo. Other NAD+ precursors have been shown to decrease weight gain; however, their impact on adipose tissue is not addressed. METHODS AND RESULTS: Two doses of NAM (high dose: 1% and low dose: 0.25%) are given by drinking water to C57BL/6J male mice, starting at the same time as the high-fat diet feeding. NAM supplementation protects against diet-induced obesity by augmenting global body energy expenditure in C57BL/6J male mice. The manipulation markedly alters adipose morphology and metabolism, particularly in inguinal (i) white adipose tissue (iWAT). An increased number of brown and beige adipocyte clusters, protein abundance of uncoupling protein 1 (UCP1), mitochondrial activity, adipose NAD+ , and phosphorylated AMP-activated protein kinase (P-AMPK) levels are observed in the iWAT of treated mice. Notably, a significant improvement in hepatic steatosis, inflammation, and glucose tolerance is also observed in NAM high-dose treated mice. CONCLUSION: NAM influences whole-body energy expenditure by driving changes in the adipose phenotype. Thus, NAM is an attractive potential treatment for preventing obesity and associated complications.

Assessment of hepatic steatosis by controlled attenuation parameter using the M and XL probes: an individual patient data meta-analysis.

BACKGROUND: Diagnostic tools for liver disease can now include estimation of the grade of hepatic steatosis (S0 to S3). Controlled attenuation parameter (CAP) is a non-invasive method for assessing hepatic steatosis that has become available for patients who are obese (FibroScan XL probe), but a consensus has not yet been reached regarding cutoffs and its diagnostic performance. We aimed to assess diagnostic properties and identify relevant covariates with use of an individual patient data meta-analysis. METHODS: We did an individual patient data meta-analysis, in which we searched PubMed and Web of Science for studies published from database inception until April 30, 2019. Studies reporting original biopsy-controlled data of CAP for non-invasive grading of steatosis were eligible. Probe recommendation was based on automated selection, manual assessment of skin-to-liver-capsule distance, and a body-mass index (BMI) criterion. Receiver operating characteristic methods and mixed models were used to assess diagnostic properties and covariates. Patients with non-alcoholic fatty liver disease (NAFLD) were analysed separately because they are the predominant patient group when using the XL probe. This study is registered with PROSPERO, CRD42018099284. FINDINGS: 16 studies reported histology-controlled CAP including the XL probe, and individual data from 13 papers and 2346 patients were included. Patients with a mean age of 46·5 years (SD 14·5) were recruited from 20 centres in nine countries. 2283 patients had data for BMI; 673 (29%) were normal weight (BMI <25 kg/m2), 530 (23%) were overweight (BMI ≥25 to <30 kg/m2), and 1080 (47%) were obese (BMI ≥30 kg/m2). 1277 (54%) patients had NAFLD, 474 (20%) had viral hepatitis, 285 (12%) had alcohol-associated liver disease, and 310 (13%) had other liver disease aetiologies. The XL probe was recommended in 1050 patients, 930 (89%) of whom had NAFLD; among the patients with NAFLD, the areas under the curve were 0·819 (95% CI 0·769-0·869) for S0 versus S1 to S3 and 0·754 (0·720-0·787) for S0 to S1 versus S2 to S3. CAP values were independently affected by aetiology, diabetes, BMI, aspartate aminotransferase, and sex. Optimal cutoffs differed substantially across aetiologies. Risk of bias according to QUADAS-2 was low. INTERPRETATION: CAP cutoffs varied according to cause, and can effectively recognise significant steatosis in patients with viral hepatitis. CAP cannot grade steatosis in patients with NAFLD adequately, but its value in a NAFLD screening setting needs to be studied, ideally with methods beyond the traditional histological reference standard. FUNDING: The German Federal Ministry of Education and Research and Echosens.

The Impact of Nonalcoholic Fatty Liver Disease in Primary Care: A Population Health Perspective.

Nonalcoholic fatty liver disease (NAFLD) is the leading cause of liver disease worldwide, with rising rates in parallel to those of obesity, type 2 diabetes, and metabolic syndrome. NAFLD encompasses a wide spectrum of pathology from simple steatosis to nonalcoholic steatohepatitis (NASH) and cirrhosis, which are linked to poor outcomes. Studies confirm a significant amount of undiagnosed NAFLD and related fibrosis within the community, increasing the overall burden of the disease. NAFLD appears to be more prevalent in certain populations, such as those with type 2 diabetes and metabolic syndrome. Early detection and lifestyle modifications, including weight loss and regular exercise, have been shown to improve outcomes. Adverse cardiovascular events are a key contributor to NAFLD-associated morbidity and mortality, and efforts to minimize their occurrence are essential. A targeted and algorithmic approach using noninvasive diagnostic techniques is promptly required to identify and risk-stratify patients with NAFLD. Patients at low risk of progression to NASH and advanced fibrosis can be managed in the primary care setting, while those at high risk of disease progression should be referred to hepatology specialists for surveillance and treatment. This review summarizes the key data of NAFLD's impact within primary care populations and proposes a potential algorithmic approach to identifying and managing such patients.

A Nomogram Model Based on Noninvasive Bioindicators to Predict 3-Year Risk of Nonalcoholic Fatty Liver in Nonobese Mainland Chinese: A Prospective Cohort Study.

The purpose of this study is to establish and validate an accurate and personalized nonalcoholic fatty liver disease (NAFLD) prediction model based on the nonobese population in China. This study is a secondary analysis of a prospective study. We included 6,155 nonobese adults without NAFLD at baseline, with a median follow-up of 2.3 years. Univariate and multivariate Cox regression analyses were used to determine independent predictors. The least absolute shrinkage and selection operator (LASSO) regression analysis was used to optimize the selection of variables. Based on the results of multivariate analysis, a prediction model was established. Harrell's consistency index (C-index) and area under the curve (AUC) were used to determine the discrimination of the proposed model. The goodness of fit of the calibration model was tested, and the clinical application value of the model was evaluated by decision curve analysis (DCA). The participants were randomly divided into a training cohort (n = 4,605) and a validation cohort (n = 1,550). Finally, seven of the variables (HDL-c, BMI, GGT, ALT, TB, DBIL, and TG) were included in the prediction model. In the training cohort, the C-index and AUC value of this prediction model were 0.832 (95% confidence interval (CI), 0.820-0.844) and 0.861 (95% CI, 0.849-0.873), respectively. In the validation cohort, the C-index and AUC values of this prediction model were 0.829 (95% CI, 0.806-0.852) and 0.859 (95% CI, 0.841-0.877), respectively. The calibration plots demonstrated good agreement between the estimated probability and the actual observation. DCA demonstrated a clinically effective predictive model. Our nomogram can be used as a simple, reasonable, economical, and widely used tool to predict the 3-year risk of NAFLD in nonobese populations in China, which is helpful for timely intervention and reducing the incidence of NAFLD.

Dysfunction of estrogen-related receptor alpha-dependent hepatic VLDL secretion contributes to sex disparity in NAFLD/NASH development.

Rationale: Men and postmenopausal women are more prone to developing non-alcoholic fatty liver disease/steatohepatitis (NAFLD/NASH) than premenopausal women. However, the pathological links and underlying mechanisms of this disparity are still elusive. The sex-difference in hepatic very low-density lipoprotein (VLDL) assembly and secretion may contribute to NAFLD development. Estrogen-related receptor alpha (ERRα) is a key regulator of several metabolic processes. We hypothesized that ERRα plays a role contributing to the sex-difference in hepatic VLDL assembly and secretion. Methods: VLDL secretion and essential genes governing said process were assessed in male and female mice. Liver-specific ERRα-deficient (ERRαLKO) mice were generated to assess the rate of hepatic VLDL secretion and alteration in target gene expression. Overexpression of either microsomal triglyceride transfer protein (Mttp) or phospholipase A2 G12B (Pla2g12b) by adenovirus was performed to test if the fatty liver phenotype in male ERRαLKO mice was due to defects in hepatic VLDL secretion. Female ERRαLKO mice were put on a diet high in saturated fat, fructose and cholesterol (HFHC) to promote NASH development. Wild type female mice were either ovariectomized or treated with tamoxifen to induce a state of estrogen deficiency or disruption in estrogen signaling. Adenovirus was used to overexpress ERRα in these mice to test if ERRα was sufficient to rescue the suppressed VLDL secretion due to estrogen dysfunction. Finally, wild type male mice on a high-fat diet (HFD) were treated with an ERRα inverse agonist to assess if suppressing ERRα activity pharmacologically would lead to fatty liver development. Results: ERRα is an indispensable mediator modulating hepatic triglyceride-rich very low-density lipoprotein (VLDL-TG) assembly and secretion through coordinately controlling target genes apolipoprotein B (Apob), Mttp and Pla2g12b in a sex-different manner. Hepatic VLDL-TG secretion is blunted in ERRαLKO mice, leading to hepatosteatosis which exacerbates endoplasmic reticulum stress and inflammation paving ways for NASH development. Importantly, ERRα acts downstream of estrogen/ERα signaling in contributing to the sex-difference in hepatic VLDL secretion effecting hepatic lipid homeostasis. Conclusions: Our results highlight ERRα as a key mediator which contributes to the sex disparity in NAFLD development, suggesting that selectively restoring ERRα activity in the liver may be a novel strategy for treating NAFLD/NASH.

Combined effects of lifestyle risk factors on fatty liver index.

BACKGROUND: Factors of lifestyle may have a major impact on liver-related morbidity and mortality. We examined independent and joint effects of lifestyle risk factors on fatty liver index (FLI), a biomarker of hepatic steatosis, in a population-based cross-sectional national health survey. METHODS: The study included 12,368 participants (5784 men, 6584 women) aged 25-74 years. Quantitative estimates of alcohol use, smoking, adiposity and physical activity were used to establish a total score of risk factors, with higher scores indicating an unhealthier lifestyle. FLI was calculated based on an algorithm including body mass index, waist circumference, serum gamma-glutamyltransferase and triglycerides. RESULTS: The occurrence of FLI ≥ 60% indicating fatty liver increased from 2.4% in men with zero risk factors to 81.9% in those with a total risk score of 7-8 (p <  0.0005 for linear trend) and in women from 0 to 73.5% (p <  0.0005). The most striking individual impacts on the likelihood for FLI above 60% were observed for physical inactivity (p <  0.0005 for both genders) and alcohol consumption (p <  0.0005 for men). Interestingly, coffee consumption was also found to increase with increasing risk factor scores (p <  0.0005 for linear trend in both genders). CONCLUSIONS: The data indicates that unfavorable combinations of lifestyle risk factors lead to a high likelihood of hepatic steatosis. Use of FLI as a diagnostic tool may benefit the assessment of interventions aimed at maintaining a healthy lifestyle and prevention of liver-related morbidity.

The epidemiology of NAFLD in Mainland China with analysis by adjusted gross regional domestic product: a meta-analysis.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a leading cause of chronic liver disease worldwide. This study aimed to estimate the prevalence, incidence, and outcome of NAFLD in the large and diverse population of Mainland China. METHODS: PubMed, Embase, and the Cochrane Library databases were searched to identify published studies with NAFLD epidemiology data in adult participants (≥ 18 years old) from Mainland China. Random effects models were used to determine pooled estimates. RESULTS: We screened 1,328 studies and included 167 eligible studies (participant n = 1,486,635): 149 studies (n = 1,350,819) for prevalence, 18 studies (n = 147,316) for incidence, 7 studies (n = 5446) for evolution of hepatic steatosis, and 2 studies (n = 647) for mortality analysis. The NAFLD prevalence of the overall populations was 29.88%, with higher rates in males, increasing age and increasing gross regional domestic product (GRDP) per capita (all p ≤ 0.010). The prevalence was the highest in North China (36.41%; higher in Uyghur and Hui Chinese 40.86% and 34.36% vs 28.11% in Han Chinese), higher in diabetics (51.83% vs. 30.76% in non-diabetics) and in obese participants (66.21% vs. 11.72% in lean). The NAFLD incidence was 56.7 (95% CI 47.4-66.8) per 1000 person-years, higher in males and with higher GRDP per capita. The overall mortality was 7.3 (3.3-12.7) per 1000 person-years. CONCLUSIONS: The overall prevalence of NAFLD in Mainland China is about 30%. The highest prevalences were found among regions with higher income, North China, the non-Han ethnic minorities, diabetics, and the obese. China's NAFLD prevalence is on par with Western countries.

Prediction of Liver Steatosis Applying a New Score in Subjects from the Brazilian Longitudinal Study of Adult Health.

GOALS: To develop a noninvasive algorithm for diagnosis of liver steatosis and to compare its diagnostic value with available predictive models. BACKGROUND: Liver steatosis represents the most frequent liver disease worldwide. STUDY: This cross-sectional study analyzed data from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). Patients were randomly divided into training (n=6571) and validation (n=3286) cohort. Abdominal ultrasound (US), used to grade steatosis, and overnight fasting blood tests were performed at the same day. Fatty Liver Index (FLI), Hepatic Steatosis Index, and Nonalcoholic Fatty Liver Disease-Liver Fat Score were calculated. A backward stepwise multivariate logistic regression analysis was used to develop the new predictive model, Steato-ELSA. RESULTS: In total, 9857 subjects [58% female, age=51 (interquartile range, 45 to 58) years, body mass index=26.4 (23.9 to 29.6) Kg/m] were included. Body mass index, waist circumference, homeostasis model of assessment of insulin resistance, transaminases, and triglycerides were independently associated with steatosis in the multivariate model (Hosmer-Lemeshow P=0.279). In the validation cohort, the area under the receiver-operator characteristics (95% confidence interval) for prediction of mild and moderate steatosis were: (i) 0.768 (0.751-0.784) and 0.829 (0.810-0.848) for Steato-ELSA; (ii) 0.762 (0.745-0.779) and 0.819 (0.799-0.838) for Fatty Liver Index; (iii) 0.743 (0.727-0.761) and 0.800 (0.779-0.822) for Hepatic Steatosis Index; and (iv) 0.719 (0.701-0.737) and 0.769 (0.747-0.791) for Nonalcoholic Fatty Liver Disease-Liver Fat Score. Steato-ELSA performed significantly better than other models and yielded sensitivity (Se)/specificity (Sp) (95% confidence interval): (i) for mild steatosis (score ≥0.386): Se=65.6% (63.0-68.3) and Sp=73.7% (71.8-75.6); (ii) for moderate steatosis (score ≥0.403): Se=83.5% (80.0-86.9) and Sp=68.7% (67.0-70.4). CONCLUSIONS: Steato-ELSA is an accurate and inexpensive tool that uses simple parameters to identify individuals at high risk of liver steatosis.

Food Insecurity May Be an Independent Risk Factor Associated with Nonalcoholic Fatty Liver Disease among Low-Income Adults in the United States.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD), considered a "barometer" of metabolic health, is the leading cause of liver disease in the United States. Despite established associations between food insecurity and obesity, hypertension, and diabetes, little is known about the relation between food insecurity and NAFLD. OBJECTIVE: We sought to evaluate the association of food insecurity with NAFLD among low-income adults in the United States. METHODS: We conducted a cross-sectional analysis of a nationally representative sample of adults from the NHANES (2005-2014 waves). Participants included adults in low-income households (≤200% of the federal poverty level) without chronic viral hepatitis or self-reported heavy alcohol use. Food insecurity was measured using the Household Food Security Survey. Our primary outcome was NAFLD, as estimated by the US Fatty Liver Index, and our secondary outcome was advanced fibrosis, as estimated by the NAFLD fibrosis score. The association between food insecurity (defined as low and very low food security) and hepatic outcomes was assessed using multivariable logistic regression, adjusting for sociodemographic factors. RESULTS: Among 2627 adults included in the analysis, 29% (95% CI: 26%, 32%) were food insecure. The median age was 43 y, 58% were female, and 54% were white. The weighted estimated prevalence of NAFLD did not differ significantly by food security status (food secure 31% compared with food insecure 34%, P = 0.21). In the multivariable model, food-insecure adults were more likely to have NAFLD (adjusted OR: 1.38; 95% CI: 1.08, 1.77) and advanced fibrosis (adjusted OR: 2.20; 95% CI: 1.27, 3.82) compared with food-secure adults. CONCLUSIONS: Food insecurity may be independently associated with NAFLD and advanced fibrosis among low-income adults in the United States. Future strategies should assess whether improved food access, quality, and healthy eating habits will decrease the growing burden of NAFLD-associated morbidity and mortality among at-risk adults.

Overview of the Pathogenesis, Genetic, and Non-Invasive Clinical, Biochemical, and Scoring Methods in the Assessment of NAFLD.

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease worldwide. It represents a range of disorders, including simple steatosis, nonalcoholic steatohepatitis (NASH), and liver cirrhosis, and its prevalence continues to rise. In some cases, hepatocellular carcinoma (HCC) may develop. The develop;ment of non-invasive diagnostic and screening tools is needed, in order to reduce the frequency of liver biopsies. The most promising methods are those able to exclude advanced fibrosis and quantify steatosis. In this study, new perspective markers for inflammation, oxidative stress, apoptosis, and fibrogenesis; emerging scoring models for detecting hepatic steatosis and fibrosis; and new genetic, epigenetic, and multiomic studies are discussed. As isolated biochemical parameters are not specific or sensitive enough to predict the presence of NASH and fibrosis, there is a tendency to use various markers and combine them into mathematical algorithms. Several predictive models and scoring systems have been developed. Current data suggests that panels of markers (NAFLD fibrosis score, Fib-4 score, BARD score, and others) are useful diagnostic modalities to minimize the number of liver biopsies. The review unveils pathophysiological aspects related to new trends in current non-invasive biochemical, genetic, and scoring methods, and provides insight into their diagnostic accuracies and suitability in clinical practice.

A review of the use of transient elastography in the assessment of fibrosis and steatosis in the post-liver transplant patient.

Liver biopsy is considered the gold standard method for diagnosing and staging liver disease, particularly in the post-liver transplant setting. Given the invasive nature of biopsy, alternate means for accurately assessing liver fibrosis and steatosis are preferred especially as the number of patients with fatty liver disease is increasing. Transient elastography has been validated as a useful tool for evaluation of liver fibrosis, as has controlled attenuation parameter index as a tool for assessing steatosis. It is a non-invasive, rapid, and highly reproducible approach to demonstrate the presence of fibrosis among non-transplant patients with chronic liver disease of various etiologies. However, it has not yet found wide acceptance in liver transplant recipients. There are few published studies evaluating the merits and applicability of transient elastography to assess allografts after liver transplantation. We review the published data on the use of transient elastography with concurrent controlled attenuation parameter in liver transplant recipients and recommend its greater use to follow allograft function over time.