Exercise and diet modification in non-obese non-alcoholic fatty liver disease: analysis of biopsies of living liver donors

Increased risk of young-onset ovarian cancer in women with non-alcoholic fatty liver disease: A nationwide cohort study of 2.3 million women aged 20-39 years

Little is known about modifiable risk factors for young-onset ovarian cancer, except for obesity and nulliparity. We investigated the association between non-alcoholic fatty liver disease (NAFLD) and the risk of young-onset ovarian cancer. A total of 2,376,482 women aged 20-39 years who underwent national health screening under the Korean National Health Insurance Service between 2009 and 2012 were included in this nationwide cohort study and followed-up until December 2022. The fatty liver index was used as a diagnostic biomarker for NAFLD. The risk was estimated using multivariable Cox proportional hazards models after adjusting for potential confounders. During 26.8 million person-years of follow-up (median: 11.5 years), 6,319 young women were newly diagnosed with young-onset ovarian cancer. The cumulative incidence probability was significantly higher for those with NAFLD than for those without (log-rank P < 0.01). NAFLD was associated with an increased risk of young-onset ovarian cancer (adjusted hazard ratio [aHR], 95% confidence interval [CI]: 1.30, 1.16-1.45). As the severity of NAFLD increased, the risk of young-onset ovarian cancer tended to increase (aHR, 95% CI: Moderate and severe NAFLD; 1.26, 1.12-1.41 and 1.45, 1.22-1.72, respectively; P for trend < 0.01). NAFLD was independently associated with an increased risk of young-onset ovarian cancer. As NAFLD is modifiable, our findings may benefit the next generation by reducing premature morbidity and mortality associated with young-onset ovarian cancer.

Increased Risk of Early-Onset Endometrial Cancer in Women Aged 20-39 Years with Non-Alcoholic Fatty Liver Disease: A Nationwide Cohort Study

Background/Objectives: Given the rising incidence of early-onset endometrial cancer diagnosed before the age of 50 years, this study examined whether non-alcoholic fatty liver disease (NAFLD) served as an independent risk factor for early-onset endometrial cancer, irrespective of obesity status. Methods: This nationwide cohort study included 2,311,949 Korean women aged 20-39 years who underwent health screenings from 2009 to 2012. NAFLD severity was classified based on the fatty liver index: none (<30), moderate (30-59), and severe (≥60). Multivariable-adjusted Cox proportional hazards models were applied to estimate adjusted hazard ratios (aHRs) for early-onset endometrial cancer. Results: During a median follow-up of 7.6 years, 1289 women developed early-onset endometrial cancer. The cumulative incidence of early-onset endometrial cancer was significantly higher in women with NAFLD than in those without (log-rank p < 0.001). A dose-dependent association was observed, with increased risk corresponding to greater NAFLD severity (aHR [95% confidence interval (CI)]: moderate NAFLD, 2.38 [1.99-2.85]; severe NAFLD, 5.39 [4.44-6.53]; p for trend < 0.01). Compared with non-obese women without NAFLD, the aHRs for early-onset endometrial cancer were 2.53 [2.11-3.05] in non-obese women with NAFLD, 1.66 [1.10-2.52] in obese women without NAFLD, and 4.30 [3.60-5.13] in obese women with NAFLD (synergy index = 1.50, p < 0.01). Conclusions: NAFLD was independently associated with increased risk of early-onset endometrial cancer in both non-obese and obese women. Furthermore, young women with both NAFLD and obesity exhibited a synergistically elevated risk. Early identification and management of NAFLD may help mitigate the rapidly growing burden of early-onset endometrial cancer.

Metabolic-associated steatotic liver disease and hepatocellular carcinoma

INTRODUCTION

Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) has been introduced as a superior term to describe steatosis on a background of metabolic dysregulation and is slated to become the leading cause of HCC worldwide, as the incidence of metabolic comorbidities is increasing. As such, MASLD has evolved into an important public health issue, potentially leading to higher rates of liver mortality and end-stage liver disease. To this end, understanding the association between MASLD and HCC may allow for the identification of better interventions and novel therapeutic strategies.

AREAS COVERED

The authors provide a review of current knowledge on HCC development among patients with MASLD, with insights into molecular pathways and current and future therapeutic strategies.

EXPERT OPINION

MASLD has a strong association with the risk of HCC development, as metabolic comorbidities induce dysregulation in molecular pathways, leading to insulin-resistance, oxidative stress, and chronic inflammation, thus causing progression to cirrhosis and eventually to HCC. Therapeutic strategies focused on reducing diabetes-associated complications, as well as the prevalence of obesity and smoking can improve patient outcomes and reduce HCC incidence. Future studies on the molecular background of metabolic alterations may help devise new therapeutic approaches aiming to improve the current management of MASLD-HCC.

An insight into the updated pharmacotherapy of metabolic-associated fatty liver disease (MAFLD) or metabolic dysfunction-associated steatohepatitis (MASH) in lean individuals: a review

Metabolic-associated fatty liver disease (MAFLD) or metabolic dysfunction-associated steatohepatitis (MASH) in lean individuals represents a distinctive subset of MASH. Current pharmacotherapies, for MASH as demonstrated in clinical trials, predominantly target obese patients with limited consideration for lean MASH. We aimed to systematically review the literature on the pharmacotherapy of lean MASH. We searched standard medical databases, such as PubMed, Embase, Scopus, Cochrane CENTRAL, and ClinicalTrials.gov to identify eligible studies published in English up to 31 December 2023 regarding the effect of pharmacological interventions in individuals with lean MASH. We have summarized the role of various drug classes including peroxisome proliferator-activated receptor agonists, glucagon-like peptide-1 receptor agonists, sodium-glucose cotransporter 2 inhibitors, vitamin E, farnesoid X receptor agonists, selective thyroid hormone receptor-β agonists, and selective cholesterol absorption inhibitors. Consequently, lifestyle interventions, encompassing dietary modifications, exercise, and weight loss particularly directed at visceral obesity or achieving a reduction in body weight are recommended for all non-obese individuals with MASH. A highlight on the only available treatment recommendation for lean MASH is also presented. The available evidence regarding the efficacy of various drugs for the treatment of lean MASH is limited. Conclusive evidence is warranted from clinical trials exclusively involving lean individuals with MASH.

Review of current and new drugs for the treatment of metabolic-associated fatty liver disease

In the past 3 decades, metabolic-associated fatty liver disease (MAFLD) has emerged as a widespread liver condition, with its global prevalence on the rise. It ranks as a leading contributor to hepatocellular carcinoma (HCC) and necessitates liver transplantation. Under the multiple parallel hits model, the pathogenesis of MAFLD stems from various liver stressors, notably nutrient overload and sedentary lifestyles. While medical management for MAFLD is well-established, encompassing non-pharmaceutical and pharmaceutical interventions, determining the most effective pharmaceutical therapy has remained elusive. This review discusses diabetic medications for MAFLD treatment, emphasizing recent studies and emerging drugs while reviewing other nondiabetic agents. Emerging evidence suggests that combination therapies hold promise for resolving MAFLD and metabolic steatohepatitis (MASH) while managing side effects. Ongoing trials play a pivotal role in elucidating the effects of mono, dual, and triple receptor agonists in individuals with MASH. With the rising burden of MAFLD/MASH and its severe consequences, the need for effective treatments is more pressing than ever. This review provides a comprehensive overview of the current landscape of pharmaceutical interventions for MAFLD and MASH, shedding light on the potential of newer drugs especially diabetic medications and the importance of ongoing research in this field.

Impact of Donor Obesity on Graft and Recipient Survival Outcomes After Liver Transplantation: A Systematic Review and Meta-analysis

Background

The effect of donor body mass index (BMI) on liver transplantation (LT) outcomes remains unclear.

Methods

A systematic search of the MEDLINE, CENTRAL, Web of Science, and bibliographic reference lists was conducted. All comparative studies evaluating the outcomes of LT in obese (BMI > 30 kg/m2) and nonobese donors (BMI < 30 kg/m2) were included, and their risk of bias was assessed using the ROBINS-I assessment tool. Patient and graft survival, acute rejection, and graft failure requiring retransplantation were evaluated as outcome parameters. A random-effects model was used for outcome synthesis.

Results

We included 6 comparative studies reporting a total of 5071 liver transplant recipients from 708 obese and 4363 nonobese donors. There was no significant difference in 1-y (89.1% versus 84.0%, odds ratio [OR] 1.58; 95% CI 0.63-3.94, P = 0.33), 5-y (74.2%% versus 73.5%, OR 1.12; 95% CI 0.45-2.80, P = 0.81) graft survival, and 1-y (87.1% versus 90.3%, OR 0.71; 95% CI 0.43-1.15, P = 0.17) and 5-y (64.5% versus 71.6%, OR 0.71; 95% CI 0.49-1.05, P = 0.08) patient survival between 2 groups. Furthermore, recipients from obese and nonobese donors had a comparable risk of graft failure requiring retransplantation (OR 0.92; 95% CI 0.33-2.60, P = 0.88) or acute graft rejection (OR 0.70; 95% CI 0.45-1.11, P = 0.13).

Conclusions

A meta-analysis of the best available evidence (level 2a) demonstrates that donor obesity does not seem to have a negative impact on graft or patient outcomes. The available studies might be subject to selection bias as the grafts from obese donors are usually subject to biopsy to exclude steatosis and the recipients usually belong to the low-risk group. Future research is needed to evaluate the impact of donors subgrouped by various higher BMI on graft and patient-related outcomes as well as to capture data of the discarded grafts from obese donors; hence, selection criteria for the grafts that could be used for transplantation from obese donors is identified.

Donor body mass index over 30 is no barrier for pure laparoscopic donor right hepatectomy

Backgrounds/Aims

Challenges arise when translating pure laparoscopic donor right hepatectomy (PLDRH) results from Asian to Western donors, due to differences in body mass index (BMI). This study compares the outcomes of PLDRH and conventional open donor right hepatectomy (CDRH) in donors with BMI over 30.

Methods

Medical records of live liver donors (BMI > 30) undergoing right hepatectomy (2010-2021) were compared: 25 PLDRH cases vs. 19 CDRH cases. Donor and recipient demographics, operative details, and outcomes were analyzed.

Results

PLDRH and CDRH had similar donor and recipient characteristics. PLDRH had longer liver removal and warm ischemic times, but a shorter post-liver removal duration than CDRH. Donor complication rates were comparable, with the highest complication being grade IIIa in PLDRH, necessitating needle aspiration for biloma on postoperative day 11. Fortunately, this donor fully recovered without additional treatment. No complications exceeding Clavien-Dindo grade IIIa occurred in either group. Recipient outcomes between the groups were similar.

Conclusions

This study supports PLDRH as a viable option for donors with BMI over 30, challenging the notion that high BMI should deter considering PLDRH. The findings provide valuable insights into the safety and feasibility of PLDRH, encouraging further exploration of this technique in diverse donor populations.

Update in lean metabolic dysfunction-associated steatotic liver disease

BACKGROUND

A new nomenclature consensus has emerged for liver diseases that were previously known as non-alcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated fatty liver disease (MAFLD). They are now defined as metabolic dysfunction-associated steatotic liver disease (MASLD), which includes cardiometabolic criteria in adults. This condition, extensively studied in obese or overweight patients, constitutes around 30% of the population, with a steady increase worldwide. Lean patients account for approximately 10%-15% of the MASLD population. However, the pathogenesis is complex and is not well understood.

AIM

To systematically review the literature on the diagnosis, pathogenesis, characteristics, and prognosis in lean MASLD patients and provide an interpretation of these new criteria.

METHODS

We conducted a comprehensive database search on PubMed and Google Scholar between January 2012 and September 2023, specifically focusing on lean NAFLD, MAFLD, or MASLD patients. We include original articles with patients aged 18 years or older, with a lean body mass index categorized according to the World Health Organization criteria, using a cutoff of 25 kg/m2 for the general population and 23 kg/m2 for the Asian population.

RESULTS

We include 85 studies in our analysis. Our findings revealed that, for lean NAFLD patients, the prevalence rate varied widely, ranging from 3.8% to 34.1%. The precise pathogenesis mechanism remained elusive, with associations found in genetic variants, epigenetic modifications, and adaptative metabolic response. Common risk factors included metabolic syndrome, hypertension, and type 2 diabetes mellitus, but their prevalence varied based on the comparison group involving lean patients. Regarding non-invasive tools, Fibrosis-4 index outperformed the NAFLD fibrosis score in lean patients. Lifestyle modifications aided in reducing hepatic steatosis and improving cardiometabolic profiles, with some medications showing efficacy to a lesser extent. However, lean NAFLD patients exhibited a worse prognosis compared to the obese or overweight counterpart.

CONCLUSION

MASLD is a complex disease comprising epigenetic, genetic, and metabolic factors in its pathogenesis. Results vary across populations, gender, and age. Limited data exists on clinical practice guidelines for lean patients. Future studies employing this new nomenclature can contribute to standardizing and generalizing results among lean patients with steatotic liver disease.

Mortality and Liver-Related Events in Lean Versus Non-Lean Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Although approximately 40% of patients with nonalcoholic fatty liver disease (NAFLD) are nonobese or lean, little is known about the long-term clinical outcomes of lean NAFLD. We aimed to estimate the risk of mortality and adverse liver-related events in patients with lean NAFLD compared with those with non-lean NAFLD.

METHODS

We searched the PubMed, Embase, and Cochrane Library databases through May 2022 for articles reporting mortality and/or development of cirrhosis among lean and non-lean NAFLD patients. The relative risks (RRs) of all-cause mortality, cardiovascular mortality, liver-related mortality, and occurrence of decompensated cirrhosis or hepatocellular carcinoma were pooled using the random-effects model. We also performed subgroup analysis according to characteristics of the study population, methods of NAFLD diagnosis, study design, study region, and length of follow-up.

RESULTS

We analyzed 10 cohort studies involving 109,151 NAFLD patients. Patients with lean NAFLD had comparable risks for all-cause mortality (RR, 1.09; 95% confidence interval [CI], 0.66-1.90), cardiovascular mortality (RR, 1.12; 95% CI, 0.66-1.90), and adverse liver events including decompensated cirrhosis and hepatocellular carcinoma (RR, 0.81; 95% CI, 0.50-1.30). However, the risk of liver-related mortality was higher in patients with lean than non-lean NAFLD (RR, 1.88; 95% CI, 1.02-3.45).

CONCLUSIONS

This study highlights a higher risk of liver-related mortality in patients with lean NAFLD than those with non-lean NAFLD. This finding indicates that further understanding of the pathophysiology, risk factors of adverse outcomes, and genetic and ethnic variabilities of lean NAFLD phenotype is warranted for individualized treatment strategies in lean NAFLD patients.

Epigenetic Regulation in Lean Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD), the most prominent cause of chronic liver disease worldwide, is a rapidly growing epidemic. It consists of a wide range of liver diseases, from steatosis to nonalcoholic steatohepatitis, and predisposes patients to liver fibrosis, cirrhosis, and even hepatocellular carcinoma. NAFLD is strongly correlated with obesity; however, it has been extensively reported among lean/nonobese individuals in recent years. Although lean patients demonstrate a lower prevalence of diabetes mellitus, central obesity, dyslipidemia, hypertension, and metabolic syndrome, a percentage of these patients may develop steatohepatitis, advanced liver fibrosis, and cardiovascular disease, and have increased all-cause mortality. The pathophysiological mechanisms of lean NAFLD remain vague. Studies have reported that lean NAFLD demonstrates a close association with environmental factors, genetic predisposition, and epigenetic modifications. In this review, we aim to discuss and summarize the epigenetic mechanisms involved in lean NAFLD and to introduce the interaction between epigenetic patterns and genetic or non genetic factors. Several epigenetic mechanisms have been implicated in the regulation of lean NAFLD. These include DNA methylation, histone modifications, and noncoding-RNA-mediated gene regulation. Epigenetics is an area of special interest in the setting of lean NAFLD as it could provide new insights into the therapeutic options and noninvasive biomarkers that target this under-recognized and challenging disorder.

Non-alcoholic Steatohepatitis in Asians: Current Perspectives and Future Directions

Non-alcoholic steatohepatitis (NASH) is a subset of non-alcoholic fatty liver disease (NAFLD), which, apart from excess fat in the liver, may be characterised by some level of inflammatory infiltration and fibrogenesis, occasionally progressing to liver cirrhosis or hepatocellular carcinoma (HCC). The objective of the current review is to elucidate the rising prevalence, the role of microbiome and genetics in pathogenesis, diagnostic challenges, and novel treatment alternatives for NASH. Newer diagnostic techniques are being developed since using liver biopsy in a larger population is not a reasonable option and is primarily restricted to clinical research, at least in developing countries. Besides these technical challenges, another important factor leading to deviation from guideline practice is the lack of health insurance coverage in countries like India. It leads to reluctance on the part of physicians and patients to delay required tests to curb out-of-pocket expenditure. There is no cure for NASH, with liver transplantation remaining the last option for those who progress to end-stage liver disease (ESLD) or are detected with early-stage HCC. Thus, lifestyle modification remains the only viable option for many, but compliance and long-term adherence remain major challenges. In obese individuals, bariatric surgery and weight reduction have shown favourable results. In patients with less severe obesity, endoscopic bariatric metabolic therapies (EBMT) are rapidly emerging as less invasive therapies. However, access and acceptability remain poor for these weight reduction methods. Therefore, intense research is being conducted for potential newer drug classes with several agents currently in phase II or III of clinical development. Some of these have demonstrated promising results, such as a reduction in hepatic fat content, and attenuation of fibrosis with an acceptable tolerability profile in phase II studies. The developments in the management of NASH have been fairly encouraging. Further well-designed long-term prospective studies should be undertaken to generate evidence with definitive results.

The Association between Cardio-metabolic and hepatic indices and anthropometric measures with metabolically obesity phenotypes: a cross-sectional study from the Hoveyzeh Cohort Study

BACKGROUND

This study aimed to compare the cardio-metabolic, anthropometric, and liver function indices among metabolic obesity phenotypes.

METHODS

In this cross-sectional study, which was carried out in Hoveyzeh, Khuzestan Province, Iran, a total of 7,464 individuals (male: 2859, female: 4605), were recruited and classified into four groups, based on Body Mass Index (obese, BMI ≥ 30 kg/m²; non-obese, BMI = 18.5-29.9 kg/m²) and the National Cholesterol Education Program and Adult Treatment Panel (NCEP ATP) III criteria (Healthy group, ≤ 1 of the criteria; Unhealthy group, ≥ 2 of the criteria), as follows: Metabolically Healthy Non-Obese (MHNO, 28.14%), Metabolically Unhealthy Non-Obese (MUNO, 33.06%), Metabolically Healthy Obese (MHO, 6.54%), and Metabolically Unhealthy Obese (MUO, 32.26%). Anthropometric indices (Waist/Hip Ratio (WHR), Waist/Height Ratio (WHtR), Body Adiposity Index (BAI), Visceral Adiposity Index (VAI), and Weight adjusted Waist Index (WWI)), cardio-metabolic indices (Atherogenic Index of Plasma (AIP), Lipid Accumulation Product (LAP), Cardio-Metabolic Index (CMI), Lipoprotein Combine Index (LCI), Triglyceride-Glucose (TyG), TyG-BMI, TyG-WC, and Thrombolysis In Myocardial Infarction (TIMI) risk index), and hepatic indices (Hepatic Steatosis Index (HSI) and ALD/NAFLD index (ANI)) were calculated and compared between the groups.

RESULTS

WHR,VAI, AIP, LAP, CMI, LCI, TyG, and TIMI risk index values were significantly higher in the MUNO phenotype compared to the MHO phenotype (WHR: 0.97 vs. 0.95; VAI: 3.16 vs. 1.33; AIP: 0.58 vs. 0.25; LAP: 78.87 vs. 55.79; CMI: 2.69 vs. 1.25; LCI: 27.91 vs. 12.11; TyG: 9.21 vs. 8.41; TIMI: 18.66 vs. 15.63; p < 0.001). The highest and lowest HSI and ANI values were detected in the MUO phenotype. After adjustment for age, sex, physical activity, and years of education, VAI showed the highest Odds Ratio for MUNO (OR: 5.65; 95% CI: 5.12, 6.24) and MUO (OR: 5.40; 95% CI: 5.89, 5.95) compared to the MHNO phenotypes (p < 0.001). The ANI indices was associated with a reduced risk of MUO (OR: 0.76; 95% CI: 0.75-0.78), MUNO (OR: 0.88; 95% CI: 0.87-0.90), and MHO (OR: 0.79; 95% CI: 0.77-0.81) phenotypes (p < 0.001).

CONCLUSION

MUNO phenotype was exposed to a higher risk of cardiovascular disease compared to the MHO phenotype. VAI was found to be the optimal index for cardiovascular risk assessment.

Nonalcoholic Fatty Liver Disease in Lean/Nonobese and Obese Individuals: A Comprehensive Review on Prevalence, Pathogenesis, Clinical Outcomes, and Treatment

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide, with an estimated prevalence of 25% globally. NAFLD is closely associated with metabolic syndrome, which are both becoming increasingly more common with increasing rates of insulin resistance, dyslipidemia, and hypertension. Although NAFLD is strongly associated with obesity, lean or nonobese NAFLD is a relatively new phenotype and occurs in patients without increased waist circumference and with or without visceral fat. Currently, there is limited literature comparing and illustrating the differences between lean/nonobese and obese NAFLD patients with regard to risk factors, pathophysiology, and clinical outcomes. In this review, we aim to define and further delineate different phenotypes of NAFLD and present a comprehensive review on the prevalence, incidence, risk factors, genetic predisposition, and pathophysiology. Furthermore, we discuss and compare the clinical outcomes, such as insulin resistance, dyslipidemia, hypertension, coronary artery disease, mortality, and progression to nonalcoholic steatohepatitis, among lean/nonobese and obese NAFLD patients. Finally, we summarize the most up to date current management of NAFLD, including lifestyle interventions, pharmacologic therapies, and surgical options.

Effects of lifestyle intervention on adults with metabolic associated fatty liver disease: A systematic review and meta-analysis

INTRODUCTION

This systematic review and meta-analysis evaluates the overall effects of lifestyle interventions upon hepatic fat content and metabolism-related indicators among adults with metabolic associated fatty liver disease.

METHODS

It was registered under PROSPERO (CRD42021251527). We searched PubMed, EMBASE, MEDLINE, Cochrane, CINAHL, Scopus, CNKI, Wan-fang, VIP, and CBM from the inception of each database to May 2021 for RCT studies of lifestyle interventions on hepatic fat content and metabolism-related indicators. We used Review Manager 5.3 for meta-analysis and used text and detailed tabular summaries when heterogeneity existed.

RESULTS

Thirty-four RCT studies with 2652 participants were included. All participants were obesity, 8% of whom also had diabetes, and none was lean or normal weight. Through subgroup analysis, we found low carbohydrate diet, aerobic training and resistance training significantly improved the level of HFC, TG, HDL, HbA1c, and HOMA-IR. Moreover, low carbohydrate diet is more effective in improving HFC than low fat diet and resistance training is better than aerobic training in reduction in HFC and TG (SMD, -0.25, 95% CI, -0.45 to -0.06; SMD, 0.24, 95% CI, 0.03 to 0.44, respectively).

DISCUSSION

Overall, this is the first review that systematically synthesizes studies focused on the effects of various lifestyle on adults with MAFLD. The data generated in this systematic review were more applicable to obesity MAFLD rather than lean or normal weight MAFLD.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/, identifier (CRD42021251527).

Recent advances in lean NAFLD

As the predominant type of chronic liver disease, the growing prevalence of nonalcoholic fatty liver disease (NAFLD) has become a concern worldwide. Although obesity plays the most pivotal role in NAFLD, approximately 10-20% of individuals with NAFLD who are not overweight or obese (BMI < 25 kg/m2, or BMI < 23 kg/m2 in Asians) have "lean NAFLD." Lean individuals with NAFLD have a lower prevalence of diabetes, hypertension, hypertriglyceridemia, central obesity, and metabolic syndrome than nonlean individuals with NAFLD, but higher fibrosis scores and rates of cardiovascular morbidity and all-cause mortality in advanced stages. The pathophysiological mechanisms of lean NAFLD remain poorly understood. Studies have shown that lean NAFLD is more correlated with factors such as environmental, genetic susceptibility, and epigenetic regulation. This review will examine the way in which the research progress and characteristic of lean NAFLD, and explore the function of epigenetic modification to provide the basis for the clinical treatment and diagnosis of lean NAFLD.

Benefits of Physical Exercise as Approach to Prevention and Reversion of Non-Alcoholic Fatty Liver Disease in Children and Adolescents with Obesity

Non-alcoholic fatty liver disease (NAFLD) is an important health concern during childhood; indeed, it is the most frequent cause of chronic liver diseases in obese children. No valid pharmacological therapies for children affected by this condition are available, and the recommended treatment is lifestyle modification, usually including nutrition and exercise interventions. In this narrative review, we summarized up-to-date information on the benefits of physical exercise on NAFLD in children and adolescents with obesity. The role of exercise as non-pharmacological treatment was emphasized in order to provide recent advances on this topic for clinicians not deeply involved in the field. Several studies on obese children and adults confirm the positive role of physical activity (PA) in the treatment of NAFLD, but to date, there are no pediatric randomized clinical trials on exercise versus usual care. Among the pathogenic mechanisms involved in the PA effects on NAFLD, the main players seem to be insulin resistance and related inflammation, oxidative stress, and gut dysbiosis, but further evaluations are necessary to deeply understand whether these factors are correlated and how they synergistically act. Thus, a deeper research on this theme is needed, and it would be extremely interesting.

Changing clinical management of NAFLD in Asia

Non-alcoholic fatty liver disease (NAFLD) has become the leading cause of chronic liver disease, affecting approximately 25% of the world's population. Recently, because of the sedentary lifestyle and overnutrition resulting from urbanisation, the burden of NAFLD has rapidly increased in many Asian countries. Currently, the prevalence of NAFLD in Asia is approximately 30%, as is the case in many Western countries. In Asia, the prevalence and presentation of NAFLD vary widely across regions because of the substantial diversity in race, socioeconomic status and living environment. Furthermore, the dual aetiology of fatty liver, particularly with viral hepatitis in Asia, makes it complex and challenging to manage. Because Asians are likely to have central adiposity and insulin resistance, approximately 7%-20% of non-obese Asians with body mass indexes of less than 25 kg/m² are estimated to have NAFLD. Accumulating evidence indicates that NAFLD is associated with various extrahepatic comorbidities such as cardiovascular disease, chronic kidney disease, malignancy, in addition to liver-specific complications. Therefore, NAFLD should be managed as a multisystem disease in conjunction with metabolic syndrome. Lifestyle modification remains the basis of NAFLD management, but few patients can achieve adequate weight loss and maintain it long term. While various pharmacological agents are in phase 3 trials for steatohepatitis, Asian patients are underrepresented in most trials. This article reviews the epidemiological trends, clinical features, optimal assessment and current management practices for NAFLD in Asia.

Clinical Factors Associated with Non-Obese Nonalcoholic Fatty Liver Disease Detected among US Adults in the NHANES 2017-2018

NAFLD can occur in non-obese individuals with BMI < 25 kg/m2. Our goal was to examine the prevalence and clinical factors associated with non-obese NAFLD using vibration-controlled transient elastography (VCTE) with controlled attenuation parameter which estimates steatosis and fibrosis among US adults. We aggregated data from the 2017−2018 cycle of NHANES and included adults (age ≥ 20 years) with BMI < 25 kg/m2 with complete data for the survey, medical examination, and VCTE along with controlled attenuation parameter (CAP). We excluded participants with risks of other liver diseases. We considered patients to have non-obese NAFLD if CAP was >285 dB/m, or non-obese NAFLD fibrosis if this CAP criteria was met and liver stiffness was >8.6 kPa. We calculated the adjusted OR and 95% CI for associations with non-obese NAFLD using multivariable logistic regression. The prevalence of non-obese NAFLD was 6.2% and Asian Americans (12.2%) had the highest non-obese NAFLD prevalence. Clinical factors associated with non-obese NAFLD were advanced age and metabolic syndrome (ORadjusted = 6.8, 95% CI 3.0−15.5). In a separate model, we found elevated glucose (ORadjusted = 4.1, 95% CI 2.1−7.9), triglycerides (ORadjusted = 3.8, 95% CI 1.7−8.5), and truncal fat (100-unit increase ORadjusted = 1.07, 95% CI: 1.04−1.10) were associated with higher odds of non-obese NAFLD. Meanwhile, low physical activity (ORadjusted = 2.9, 95% CI 1.2−7.1) was also positively associated with non-obese NAFLD. Non-obese NAFLD is prevalent in the US and is highly associated with metabolic conditions and syndrome. Our results support the importance of considering racial/ethnic differences when investigating NAFLD in a clinical setting.

CT-based visual grading system for assessment of hepatic steatosis: diagnostic performance and interobserver agreement

BACKGROUND

Hepatic steatosis (HS) can be comprehensively assessed by visually comparing the hepatic and vessel attenuation on unenhanced computed tomography (CT). We aimed to evaluate the reliability and reproducibility of a CT-based visual grading system (VGS) for comprehensive assessment of HS.

METHODS

In this retrospective study, a four-point VGS based on the visual comparison of liver and hepatic vessels was validated by six reviewers with diverse clinical experience using the unenhanced CT images of 717 potential liver donors. The diagnostic performance of VGS and quantitative indices (difference and ratio of the hepatic and splenic attenuation) to diagnose HS were evaluated using multi-reader multi-case receiver operating characteristics (ROC) analysis (reference: pathology). The interobserver agreement was assessed using Fleiss κ statistics.

RESULTS

Using the VGS, all six reviewers showed areas under the ROC curves (AUROCs) higher than 0.9 for diagnosing total steatosis (TS) ≥ 30%, macrovesicular steatosis (MaS) ≥ 30%, and MaS ≥ 10%. No difference was noted between the AUROCs of the VGS and quantitative indices (p ≥ 0.1). The reviewers showed substantial agreement (Fleiss κ, 0.61). Most discrepancies occurred between the two lowest grades of VGS (81.5%; 233/283), in which most subjects (97.0%; 226/233) had a MaS < 10%. The average-reader sensitivity and specificity of the VGS were 0.80 and 0.94 to detect TS ≥ 30% and 0.93 and 0.81 to detect MaS ≥ 10%.

CONCLUSION

VGS was reliable and reproducible in assessing HS. It may be useful as a non-invasive and simple tool for comprehensive HS assessment.

Outcomes of right lobe donors with BMI≥30 for living donor liver transplantation

BACKGROUND

Donor BMI above 30 is generally considered contraindication for donor hepatectomy. We compared the donor outcomes based on BMI threshold and weight loss.

PATIENTS AND METHODS

All potential donors were identified and data were collected retrospectively. Steatosis was assessed based on liver-spleen Hounsfield unit difference and absolute liver intensity values. We compared BMI≥30 (n = 53) and BMI<30 (n = 64) donor outcomes. Donors with weight loss (WL) prior to surgery were also analyzed separately. Complications were graded by Clavien-Dindo classification.

RESULTS

All donors underwent open right donor hepatectomy. There was no difference between BMI≥30 and <30 groups except female predominance in BMI≥30 group (p = 0.006). Both groups had similar rates of complication rates in all categories, similar remnant volume, operative time, length of stay and similar postoperative liver function recovery (all p>0.05). On the other hand, donors with WL were more commonly male, had smaller graft size, and higher biliary complications rates compared to no-WL donors (all p<0.05). Multivariate binary logistics regression analysis revealed no association between BMI or WL and outcomes.

CONCLUSION

We demonstrate that donors with BMI≥30 have similar outcomes compared to BMI<30 donors with our defined selection criterion, therefore BMI≥30 is not an absolute contraindication to donate right liver, provided that there is no significant steatosis and remnant liver is satisfactory. For potential overweight donors, WL down to BMI<30 is a reasonable target. Higher biliary complication rates after WL should be investigated further. This article is protected by copyright. All rights reserved.

Changes in Indices of Steatosis and Fibrosis in Liver Grafts of Living Donors After Weight Reduction

Background

A short-term weight reduction program for potential living donors was introduced to reduce the extent of hepatic steatosis prior to liver transplantation. We aimed to investigate changes in non-invasive hepatic steatosis and fibrosis indices among those who completed the program.

Methods

Among 1,950 potential living liver donors between January 2011 and May 2019, 160 living donors joined the weight reduction program. The prospectively collected clinical data of these potential liver donors were analyzed retrospectively. Hepatic steatosis and fibrosis scores were determined using the fatty liver index (FLI), hepatic steatosis index (HSI), and NAFLD fibrosis score (NFS) and compared to MR spectroscopy (MRS) fat fraction results before and after weight reduction.

Results

Thirty-nine potential living donors who had undergone MRS both before and after weight reduction were included in the analysis. Their body weight decreased from 78.02 ± 10.89 kg to 72.36 ± 10.38 kg over a mean of 71.74 ± 58.11 days. FLI, HSI, and MRS values decreased significantly from 41.52 ± 19.05 to 24.53 ± 15.93, 39.64 ± 3.74 to 35.06 ± 3.82, and 12.20 ± 4.05 to 6.24 ± 3.36, respectively. No significant decreases in NFS were observed. There was a significant correlation between the extent of HSI change and the extent of MRS change (R2 value = 0.69, P &lt; 0.001), although there was no correlation between MRS and FLI.

Conclusion

The weight reduction program significantly improved non-invasive indices of hepatic steatosis over a short period. HSI may allow for prediction of simple decreases in hepatic steatosis.

Mitigation of MAFLD in High Fat-High Sucrose-Fructose Fed Mice by a Combination of Genistein Consumption and Exercise Training

PURPOSE

Metabolic dysfunction-associated fatty liver disease (MAFLD) is fueled by escalations in both sedentary behavior and caloric intake and is noted in obese type 2 diabetic (T2DM) patients. This study aimed to examine the effects of exercise and the phytoestrogen genistein in mice fed a high fat (60% fat) high sugar (55% fructose with 45% sucrose), HFHS diet.

METHODS

Male C57BL/6J mice were assigned to five groups: HFHS, HFHS with genistein (600 mg/kg diet, HFHS+Gen), HFHS with moderate exercise (HFHS+Ex), and HFHS with combined genistein and moderate exercise (HFHS-Gen+Ex). Control lean mice were fed standard chow and water. Exercise consisted of 30-minute sessions of treadmill running five days/week for the 12-week study duration. Body weight was assessed weekly. Liver, kidney, fecal pellets and serum were extracted at the end of the study and maintained at -80°C.

RESULTS

After 12 weeks of treatment, mice in the HFHS group had the highest hepatic lipid content. Plasma levels of glucose, insulin, leptin, cholesterol, amylin, and total fat content were significantly elevated in HFHS mice compared to control mice. HFHS feeding increased protein expression of carnitine palmitoyltransferase 1b (CPT-1b isoform) in gastrocnemius, CPT1a, glucose transporter protein 2 (GLUT2), glucocorticoid receptor (GR), and fructose 1,6-bisphosphate 1 (FBP1) expression in liver. Exercise alone had minor effects on these metabolic abnormalities. Genistein alone resulted in improvements in body weight, fat content, amylin, insulin sensitivity, and liver histopathology, GR, FBP1, and acetyl-CoA carboxylase 1 (ACC1). Combination treatment resulted in additional metabolic improvements, including reductions in hepatic lipid content and lipid area, alanine transferase activity, CPT1b, and CPT1a.

CONCLUSION

Our results indicate that a HFHS diet is obesogenic, inducing metabolic perturbations consistent with T2DM and MAFLD. Genistein alone and genistein combined with moderate intensity exercise were effective in reducing MAFLD and the aberrations induced by chronic HFHS feeding.

Macro- and micronutrients in metabolic (dysfunction) associated fatty liver disease: association between advanced fibrosis and high dietary intake of cholesterol/saturated fatty acids

BACKGROUND AND AIM

There is still no approved pharmacotherapy for metabolic (dysfunction) associated fatty liver disease (MAFLD). Although dietary and lifestyle modifications for weight loss remain the mainstay for disease management, the association between macro- and micronutrients and fibrosis stage in patients with MAFLD remains unclear. This study was undertaken to address this issue.

METHODS

This is a retrospective analysis of prospectively collected data from patients in whom MAFLD was diagnosed with vibration controlled transient elastography. Steatosis was defined by a controlled attenuation parameter ≥238 dB/m, whereas a liver stiffness measurement ≥11 kPa was considered to indicate advanced fibrosis.

RESULTS

The study sample consisted of 106 patients with MAFLD (mean age 49 ± 10 years, 52 men and 54 women). Among the different micro- and macronutrients tested, only the dietary intake of cholesterol and saturated fatty acid (SFA) was independently associated with the presence of advanced fibrosis.

CONCLUSION

Our findings suggest that cholesterol/SFA-restricted dietary regimens - as exemplified by the traditional Mediterranean diet - may reduce the risk of advanced fibrosis in patients with MAFLD.

The presence of NAFLD in nonobese subjects increased the risk of metabolic abnormalities than obese subjects without NAFLD: a population-based cross-sectional study

BACKGROUND

With lifestyle modification and over-nutrition, the prevalence of nonalcoholic fatty liver disease (NAFLD) has been increasing annually. Here we aimed to assess the updated prevalence of NAFLD, and to evaluate the association of NAFLD with metabolic abnormalities according to gender, body mass index and age.

METHODS

A population-based cross-sectional study was conducted in Shanghai from December 2016 to July 2017. With a three-stage stratified sampling strategy, 3,717 eligible participants were enrolled for the analysis.

RESULTS

In total, 1,217 subjects (32.7%) had NAFLD. Among them, 400 (16.3%) of the nonobese and 817 (65.0%) of the obese subjects had NAFLD. The prevalence of NAFLD was increased according to the quartiles of age and waist circumference (WC) in the nonobese subjects. Females with nonobese NAFLD had 1.6-, 2.6-, 2.0-, 2.3- and 3.3-fold higher risks for metabolic syndrome, diabetes mellitus, hyperglycemia, hypertriglycerdemia (high TG) and low high-density lipoprotein cholesterol than obese subjects without NAFLD, respectively. Males had comparable metabolic profiles in both groups, except for a 2.0-fold higher risk of high TG in nonobese NAFLD subjects compared with obese subjects without NAFLD. More impressively, the homeostasis metabolic assessment insulin resistance index was comparable between the two groups.

CONCLUSIONS

The increase of age and WC had significant impact on the risk of NAFLD in nonobese subjects. The presence of NAFLD in nonobese subjects increased the risk of metabolic diseases than obese subjects without NAFLD, especially in female.

Non-Alcoholic Fatty Liver Disease in Lean and Non-Obese Individuals: Current and Future Challenges

Non-alcoholic fatty liver disease (NAFLD), which approximately affects a quarter of the world’s population, has become a major public health concern. Although usually associated with excess body weight, it may also affect normal-weight individuals, a condition termed as lean/non-obese NAFLD. The prevalence of lean/non-obese NAFLD is around 20% within the NAFLD population, and 5% within the general population. Recent data suggest that individuals with lean NAFLD, despite the absence of obesity, exhibit similar cardiovascular- and cancer-related mortality compared to obese NAFLD individuals and increased all-cause mortality risk. Lean and obese NAFLD individuals share several metabolic abnormalities, but present dissimilarities in genetic predisposition, body composition, gut microbiota, and susceptibility to environmental factors. Current treatment of lean NAFLD is aimed at improving overall fitness and decreasing visceral adiposity, with weight loss strategies being the cornerstone of treatment. Moreover, several drugs including PPAR agonists, SGLT2 inhibitors, or GLP-1 receptor agonists could also be useful in the management of lean NAFLD. Although there has been an increase in research regarding lean NAFLD, there are still more questions than answers. There are several potential drugs for NAFLD therapy, but clinical trials are needed to evaluate their efficacy in lean individuals.

Positive Effects of Exercise Intervention without Weight Loss and Dietary Changes in NAFLD-Related Clinical Parameters: A Systematic Review and Meta-Analysis

One of the focuses of non-alcoholic fatty liver disease (NAFLD) treatment is exercise. Randomized controlled trials investigating the effects of exercise without dietary changes on NAFLD-related clinical parameters (liver parameters, lipid metabolism, glucose metabolism, gut microbiota, and metabolites) were screened using the PubMed, Scopus, Web of Science, and Cochrane databases on 13 February 2020. Meta-analyses were performed on 10 studies with 316 individuals who had NAFLD across three exercise regimens: aerobic exercise, resistance training, and a combination of both. No studies investigating the role of gut microbiota and exercise in NAFLD were found. A quality assessment via the (RoB)2 tool was conducted and potential publication bias, statistical outliers, and influential cases were identified. Overall, exercise without significant weight loss significantly reduced the intrahepatic lipid (IHL) content (SMD: −0.76, 95% CI: −1.04, −0.48) and concentrations of alanine aminotransaminase (ALT) (SMD: −0.52, 95% CI: −0.90, −0.14), aspartate aminotransaminase (AST) (SMD: −0.68, 95% CI: −1.21, −0.15), low-density lipoprotein cholesterol (SMD: −0.34, 95% CI: −0.66, −0.02), and triglycerides (TG) (SMD: −0.59, 95% CI: −1.16, −0.02). The concentrations of high-density lipoprotein cholesterol, total cholesterol (TC), fasting glucose, fasting insulin, and glycated hemoglobin were non-significantly altered. Aerobic exercise alone significantly reduced IHL, ALT, and AST; resistance training alone significantly reduced TC and TG; a combination of both exercise types significantly reduced IHL. To conclude, exercise overall likely had a beneficial effect on alleviating NAFLD without significant weight loss. The study was registered at PROSPERO: CRD42020221168 and funded by the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement no. 813781.

Joint effect of changes in physical activity and weight on incident non-alcoholic fatty liver disease

BACKGROUND

Increases in physical activity (PA) and weight have opposite effects on the risk of non-alcoholic fatty liver disease (NAFLD), but their joint effect remains unknown. We examined the dose-effect of PA increase for NAFLD prevention and the amount of PA increase required to offset the deleterious effect of weight gain.

METHODS

We analysed 47 058 participants who were extracted from the Taiwan MJ cohort, aged 20-50 years, without NAFLD at baseline, and followed at 1-5 years between 1997 and 2016. The outcome was incident NAFLD, diagnosed by ultrasonography. PA was measured by metabolic equivalents (METs) and duration (hour/week). We used flexible parametric survival models to estimate the HRs of annual change in PA and body mass index (BMI), controlling for their interaction and baseline covariates.

RESULTS

During 138 646 person-years of follow-up, 12 836 participants (40.6% men and 20.1% women) developed incident NAFLD. The HR (95% CI) of annual PA increase of 1 MET-hour/week was 0.88 (0.85-0.92) after controlling for weight change. Moreover, 28 min/week of moderate-intensity PA could neutralise NAFLD risk elevated by annual BMI increase of 0.1 kg/m² at the end of year 3. We also observed an extra 35% risk reduction when PA increase (1 MET-hour/week) and weight loss (0.1 kg/m²) occurred simultaneously.

CONCLUSIONS

Annual PA increase of 1 MET-hour/week was associated with a 12% lower NAFLD risk. PA increase can counteract the harmful effect of weight gain and there is a synergistic effect from PA increase and weight loss.

A review of non-alcoholic fatty liver disease in non-obese and lean individuals

Non-alcoholic fatty liver disease (NAFLD) is one of the most common causes of hepatic disorders. It represents a wide range of chronic liver diseases in patients with no history of significant alcohol consumption, starting with simple steatosis and progressing towards non-alcoholic steatohepatitis, cirrhosis, and ultimately hepatocellular carcinoma. NAFLD is usually associated with type 2 diabetes mellitus, dyslipidemia, metabolic syndrome, and obesity. This disease has mostly been studied in obese individuals; however, it has been widely reported and studied among the lean/non-obese population in recent years. The pathogenesis of NAFLD in non-obese patients is associated with various genetic predispositions, particularly a patatin-like phospholipase domain-containing protein 3 G allele polymorphism, which results in the accumulation of triglyceride in the liver and resistance to insulin. Additionally, dietary factors such as high fructose consumption seem to play a substantial role in the pathology of non-obese NAFLD. Although there is not enough evidence on the treatment of NAFLD in non-obese patients, the standard approach is to advise altering one's lifestyle in order to diminish visceral adiposity. Dietary modification, weight loss, and increased physical activity are highly recommended. We aimed to review and summarize the existing information on the prevalence, pathogenesis, genetic predispositions, diagnosis, and treatment of NAFLD in non-obese patients according to the latest literature.

Lose Weight to Donate: Development of a Program to Optimize Potential Donors With Hepatic Steatosis or Obesity for Living Liver Donation

Background.

Living donor liver transplantation offers an attractive option to reduce the waitlist mortality. However, in recent years, the rising prevalence of obesity and nonalcoholic fatty liver disease has posed a serious threat to the donor pool while simultaneously increasing demand for liver transplant. To our knowledge, there have been no major published studies in the United States documenting a diet and exercise intervention to expand the living donor pool. Hereby, we established a pilot program called “Lose Weight to Donate” and present our initial experience.

Methods.

Our center instituted a remotely monitored diet and exercise pilot program to increase eligibility for living liver donation. Potential donors with any of the following were included: body mass index >30 kg/m², hepatic steatosis >5% on screening MRI, or isolated hypertension.

Results.

Over 19 mo, 7 individuals enrolled in the program of remote monitoring for at least 6–8 wk. Initial and follow-up abdominal MRI was performed in 5 of these individuals to assess steatosis, anatomy, and volume. Initial steatosis was highly variable (fat signal fraction range, 8%–26%). Follow-up MRI fat signal fraction values and hepatic volume all decreased to varying degrees. Ultimately, 2 of 7 individuals donated, whereas a third was approved, but the intended recipient was transplanted in the interim.

Conclusions.

These results indicate the feasibility of a remotely monitored program to expand donation in light of the rising incidence of hepatic steatosis and obesity.

Visceral fat area to appendicular muscle mass ratio as a predictor for nonalcoholic fatty liver disease independent of obesity

OBJECTIVE

Obesity and sarcopenia are known to be closely related to nonalcoholic fatty liver disease (NAFLD). We attempted to explore the combined influence of fat and muscle tissue on NAFLD by using visceral fat area to appendicular muscle mass ratio (VAR) as a novel parameter.

MATERIAL AND METHODS

In this cross-sectional study, a total of 3255 adults (1399 men and 1856 women) coming for a health examination were enrolled. NAFLD was diagnosed using ultrasound and VAR was measured by bioelectrical impedance analyzer.

RESULTS

The prevalence of NAFLD was 46.5% in men and 26.6% in women. VAR differed significantly between subjects with and without NAFLD (4.27 vs. 3.26 in men, 7.89 vs. 5.01 in women, respectively, p < .001). Logistic regression analysis determined VAR as a risk factor for NAFLD, and the multivariable-adjusted odds ratios in the highest VAR quartile was 9.57 (95%CI: 5.98-15.30) for men and 12.37 (95%CI: 6.37-24.05) for women. From the receiver operating characteristic analysis, the area under the curve was 0.767 and 0.834, with the suitable cut-off VAR value of 3.469 and 6.357 for men and women, respectively. To control the influence of obesity, all subjects were stratified according to their BMI. For each BMI group, individuals with VAR above the cut-off value had significant higher prevalence and risk of NAFLD, with odds ratios ranging from 1.76 to 4.75.

CONCLUSIONS

Increased VAR is strongly associated with higher risk of NAFLD in both sexes independent of obesity and can serve as a screening reference for NAFLD.

The Impact of Dietary Patterns and Nutrition in Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) has become one of the most common causes of chronic liver disease worldwide. The prevalence of NAFLD has grown proportionally with the rise in obesity, sedentary lifestyle, unhealthy dietary patterns, and metabolic syndrome. Currently, in the absence of approved pharmacologic treatment, the keystone of treatment is lifestyle modification focused on achieving a weight loss of 7%-10%, cardiovascular exercise, and improving insulin sensitivity. The primary aim of this review is to outline the effect of different dietetic approaches against NAFLD and highlight the important micronutrient components in the management of NAFLD.

Diversity in NAFLD: A Review of Manifestations of Nonalcoholic Fatty Liver Disease in Different Ethnicities Globally

Globally, the rise in prevalence of obesity and metabolic syndrome as a whole has been linked to increased access to processed foods, such as refined sugars and saturated fats. Consequently, nonalcoholic fatty liver disease (NAFLD) is on the rise in both developed and developing nations. However, much is still unknown on the NAFLD phenotype with regards to the effect of ethnic diversity. Despite similarities in dietary habits, it appears that certain ethnicities are more protected against NAFLD than others. However, manifestations of the same genetic polymorphisms in different groups of people increase those individuals' predisposition to NAFLD. Diets from different regions have been associated with a lower prevalence of NAFLD and have even been linked to regression of hepatic steatosis. Socioeconomic variations amongst different regions of the world also contribute to NAFLD prevalence and associated complications. Thus, a thorough understanding of ethnic variability in NAFLD is essential to tailoring treatment recommendations to patients of different backgrounds.

Gender-specific association between non-alcoholic fatty liver disease and type 2 diabetes mellitus among a middle-aged and elderly Chinese population: An observational study

ABSTRACT

Limited data are available regarding the association of non-alcoholic fatty liver disease (NAFLD) with the risk of type 2 diabetes mellitus (T2DM) in China. Therefore, the purpose of this study is to evaluate the gender-specific association between NAFLD and T2DM risk in a middle-aged and elderly Chinese population.This cross-sectional study was carried out in a group of 1492 Chinese adults (60.30% males) aged between 45 and 69 years old, in Hangzhou city, Zhejiang province who were attending their annual health check-up from June 2015 to December 2016 in the Medical Center for Physical Examination, Zhejiang Hospital. Face-to-face interviews were conducted using a written questionnaire. NAFLD was divided into none, mild, moderate/severe based on ultrasound examination. Logistic regression analyses were employed to determine the relationship between NAFLD and the risk of T2DM, with adjustment of potential confounding variables.Of the 1492 participants, 163 (10.92%) were diagnosed with T2DM. Educational level, smoking, body mass index (BMI), waist circumference (WC), waist-hip ratio (WHR), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting glucose (FG), triglycerides (TG), alanine aminotransferase (ALT), asparagine aminotransferase (AST)and the prevalence of T2DM were significantly higher in males than in females (P < .05). Besides, females had significantly higher levels of high density lipoprotein-cholesterol (HDL-C) (1.51 ± 0.37 vs 1.29 ± 0.42, P < .001) than males. Pearson bivariate correlation analysis indicated that FG was positively associated with weight, BMI, WC, WHR, SBP, DBP, TG, TC, ALT and AST in both males and females (P < .05). Besides, FG was inversely associated with HDL-C in females (P < .001). After adjusting for confounding variables, NAFLD was positively associated with the risk of T2DM, and the effect of NAFLD on T2DM was stronger in males (OR = 2.442, 95%CI: 1.003-3.757) than in females (OR = 1.814, 95%CI: 1.011-3.257).Our data showed that NAFLD was significantly associated with the risk of T2DM in middle-aged and elderly males than in females. Further prospective cohort studies are needed to determine the causal effect of NAFLD on T2DM.

The metabolic profiles and body composition of lean metabolic associated fatty liver disease

BACKGROUND/PURPOSE

Metabolic associated fatty liver disease (MAFLD) is the commonest cause of chronic liver disease, which is associated with obesity and diabetes. However, it also occurs in lean individuals especially in Asian populations.

METHODS

The participants of Tzu Chi MAFLD cohort (TCMC) including health controls or MAFLD patients were enrolled. MAFLD was defined as fatty liver in imaging without hepatitis B virus, hepatitis C virus infection, drug, alcohol or other known causes of chronic liver disease. Lean MAFLD was defined as MAFLD in lean subjects (BMI < 23 kg/m²).

RESULTS

A total of 880 subjects were included for final analysis. Of 394 MAFLD patients, 65 (16.5%) patients were diagnosed as lean MAFLD. Lean MAFLD patients were elder, higher percentage of female gender, lower ALT, diastolic blood pressure, triglyceride, and waist circumference but higher HDL than non-lean MAFLD patients. Using binary regression analysis, elder age and lower waist circumference were associated with lean MAFLD. Compared with lean healthy controls, lean MAFLD patients had higher BMI, waist circumference, and percentage of hypertension. In body composition, fatty tissue index (FTI), lean tissue index (LTI) ,and total body water (TBW) were lower in lean MAFLD than non-lean MAFLD patients; but they were comparable with lean healthy controls.

CONCLUSIONS

The prevalence of lean MAFLD was 16.5% in this study population and it was higher in elder age, especially of female subjects. Lean MAFLD patients had different metabolic profiles compared with lean healthy controls, but different body composition compared with non-lean MAFLD patients.

The Asian Pacific Association for the Study of the Liver clinical practice guidelines for the diagnosis and management of metabolic associated fatty liver disease

Metabolic associated fatty liver disease (MAFLD) is the principal worldwide cause of liver disease and affects nearly a quarter of the global population. The objective of this work was to present the clinical practice guidelines of the Asian Pacific Association for the Study of the Liver (APASL) on MAFLD. The guidelines cover various aspects of MAFLD including its epidemiology, diagnosis, screening, assessment, and treatment. The document is intended for practical use and for setting the stage for advancing clinical practice, knowledge, and research of MAFLD in adults, with specific reference to special groups as necessary. The guidelines also seek to improve patient care and awareness of the disease and assist stakeholders in the decision-making process by providing evidence-based data. The guidelines take into consideration the burden of clinical management for the healthcare sector.

Nonalcoholic fatty liver disease in lean subjects: Prognosis, outcomes and management

Nonalcoholic fatty liver disease (NAFLD) accounts for most cases of chronic liver disease worldwide, with an estimated global prevalence of approximately 25% and ranges from simple steatosis to nonalcoholic steatohepatitis and cirrhosis. NAFLD is strongly connected to metabolic syndrome, and for many years, fatty liver was considered to be an exclusive feature of obese patients. However, recent studies have highlighted the presence of NAFLD in non-obese subjects, with or without increased visceral fat or even in lean subjects without increased waist circumference. "Lean NAFLD" is a relatively new concept and there is significant scientific interest in understanding the differences in pathophysiology, prognosis and management compared with NAFLD in overweight/obese patients. In the present editorial, we discuss the clinical and metabolic profiles and outcomes of lean NAFLD compared with both obese NAFLD and lean healthy individuals from Asian and Western countries. Moreover, we shed light to the challenging topic of management of NAFLD in lean subjects since there are no specific guidelines for this population. Finally, we discuss open questions and issues to be addressed in the future in order to categorize NAFLD patients into lean and non-lean cohorts.

Role of intensive dietary and lifestyle interventions in the treatment of lean nonalcoholic fatty liver disease patients

BACKGROUND/AIM

Although weight loss is recommended for the treatment of nonalcoholic fatty liver disease (NAFLD) in overweight and obese individuals, this treatment modality remains questionable in lean individuals. In this study, we investigated the effects of medical nutrition therapy (MNT) and intensive lifestyle interventions (ILIs) for NAFLD in lean versus obese patients.

METHODS

In total, 35 patients (14 lean and 21 obese) were included in the study. All patients underwent transient elastography examinations, and controlled attenuation parameter (CAP) of >238 dB/m was indicative of hepatic steatosis. After 8 weeks of dietitian follow-up with MNT and ILI, the patients were compared with the baseline.

RESULTS

Significant weight loss was recorded in both lean (5.4%) and obese patients (5.7%) with NAFLD. The mean BMI decreased from 23.9 (20.5-24.8) to 22.4 (19.5-24.2) kg/m (P = 0.001) in lean patients and from 34.0 (30.0-42.0) to 31.6 (26.9-42.5) kg/m (P < 0.001) in obese patients. The alanine aminotransferase level significantly decreased from 56 (15-163) to 28 (13-98) U/L (P = 0.010) in lean patients and from 27 (13-81) to 22 (13-46) U/L (P = 0.018) in obese patients. The median CAP decreased from 299 (246-360) to 236 (169-318) dB/m (P = 0.002) in lean patients and from 325 (258-400) to 253 (202-383) dB/m (P < 0.001) in obese patients. Moreover, remission of hepatic steatosis was detected in eight lean patients (57.1%) and eight obese patients (38.1%).

CONCLUSION

These results indicate that 5% body weight loss in effective in both obese and lean patients resulting in a similar NAFLD remission.

Morphological evaluation of the effects of exercise on high-fat-diet-induced liver damage in rats

BACKGROUND/AIMS

This study was aimed to investigate the protective effects of swimming exercise on nonalcoholic fatty liver disease (NAFLD) associated with high fat diet-induced obesity, using microscopical and biochemical parameters.

MATERIALS AND METHODS

Sprague Dawley male rats were fed either standard chow (STD group; 6% fat) or high-fat diet (HFD group; 45% fat) for 18 weeks. Animals were divided into four groups, STD, STD + EXC, HFD, HFD + EXC. Exercise groups were submitted to swimming training 5 days of week and 1h of per day, during the last 6 weeks of the experiment. At the end of the experiment, liver samples were evaluated for morphologically and ultrastructurally. Moreover, malondialdehyde (MDA) and glutathione (GSH) levels were evaluated in liver samples.

RESULTS

Normal morphology of liver parancyma with hepatocytes and sinusoids was observed in the STD and STD+EXC groups. Steatosis, lipid accumulation, ballooned hepatocytes, decrease of glycogen deposits and fibrosis in periportal area were observed in HFD group. Liver MDA level was increased and GSH level was decreased in HFD group. Exercise treatment ameliorated these morphological and oxidative changes in HFD induced liver damage.

CONCLUSION

Based on morphological and biochemical analysis, we could conclude that swimming training ameliorated obesity-induced liver damage by regulating lipid accumulation and oxidative damage.

Impact of obesity and metabolic health status in the development of non-alcoholic fatty liver disease (NAFLD): A United Kingdom population-based cohort study using the health improvement network (THIN)

BACKGROUND

With the obesity epidemic reaching crisis levels, there has been attention around those who may be resilient to the effects of obesity, termed metabolically healthy obesity (MHO), who initially present without associated metabolic abnormalities. Few longitudinal studies have explored the relationship between MHO and non-alcoholic fatty liver disease (NAFLD), which we address using over 4 million primary care patient records.

METHODS

A retrospective population-based longitudinal cohort was conducted using The Health Improvement Network (THIN) database incorporating adults with no history of NAFLD or alcohol excess at baseline. Individuals were classified according to BMI category and metabolic abnormalities (diabetes, hypertension and dyslipidaemia). Diagnosis of NAFLD during follow-up was the primary outcome measure. NAFLD was identified by Read codes.

RESULTS

During a median follow-up period of 4.7 years, 12,867 (0.3%) incident cases of NAFLD were recorded in the cohort of 4,121,049 individuals. Compared to individuals with normal weight and no metabolic abnormalities, equivalent individuals who were overweight, or obese were at significantly greater risk of incident NAFLD (Adjusted HR 3.32 (95%CI 2.98-3.49), and 6.92 (6.40-7.48, respectively). Metabolic risk factors further increased risk, including in those with normal weight and 1 (2.27, 1.97-2.61) or = < 2 (2.39, 1.99-2.87) metabolic abnormalities.

CONCLUSIONS

MHO individuals are at greater risk of developing NAFLD compared to those with normal weight. This finding supports that the MHO phenotype is a temporary state, and weight must be considered a risk factor even before other risk factors develop. Being normal weight with metabolic abnormalities was also associated with risk of NAFLD.

Decrease in waist-to-hip ratio reduced the development of chronic kidney disease in non-obese non-alcoholic fatty liver disease

To date, there are few studies that have evaluated the prognostic impact of changes in abdominal obesity or weight on long-term adverse kidney outcomes in non-alcoholic fatty liver disease (NAFLD). We investigated the effect of changes in waist-to-hip ratio (WHR) and body weight (BW) on chronic kidney disease (CKD) development, especially in non-obese NAFLD patients. We included 6,137 participants from a community-based prospective cohort with 12-year follow-up in Korea. NAFLD patients were categorized according to time-averaged percent changes in WHR and BW (≤−5%, >−5% to <5%, and ≥5%). Compared to non-obese controls, non-obese NAFLD was significantly associated with an increased risk of incident CKD (hazard ratio [HR] = 1.238, 95% confidence interval [CI] = 1.006–1.524). In 1,563 NAFLD patients, compared to patients with minimal changes in WHR (>−5% to <5%), patients with a decreased WHR (≤−5%) had a significantly attenuated risk of CKD development (HR = 0.300; 95% CI = 0.194–0.464). Furthermore, risk reduction from decreased WHR for developing CKD remained significant in non-obese NAFLD patients (HR = 0.290; 95% CI = 0.114–0.736). In conclusion, a decrease in WHR of more than 5% significantly reduced the risk of CKD development in NAFLD patients, even in those who were non-obese. Thus, serial monitoring of WHR may be prioritized in the management of NAFLD.

Exercise Attenuates the Transition from Fatty Liver to Steatohepatitis and Reduces Tumor Formation in Mice

Non-alcoholic fatty liver disease (NAFLD) leads to steatohepatitis (NASH), fibrosis, and hepatocellular carcinoma. For sedentary patients, lifestyle interventions combining exercise and dietary changes are a cornerstone of treatment. However, the benefit of exercise alone when dietary changes have failed is uncertain. We query whether exercise alone arrests the progression of NASH and tumorigenesis in a choline-deficient, high-fat diet (CD-HFD) murine model. Male C57Bl/6N mice received a control diet or CD-HFD for 12 weeks. CD-HFD mice were randomized further for 8 weeks of sedentariness (SED) or treadmill exercise (EXE). CD-HFD for 12 weeks produced NAFL. After 20 weeks, SED mice developed NASH and hepatic adenomas. Exercise attenuated the progression to NASH. EXE livers showed lower triglycerides and tumor necrosis factor-α expression, less fibrosis, less ballooning, and a lower NAFLD activity score than did SED livers. Plasma transaminases and triglycerides were lower. Exercise activated AMP-activated protein kinase (AMPK) with inhibition of mTORC1 and decreased S6 phosphorylation, reducing hepatocellular adenoma. Exercise activated autophagy with increased LC3-II/LC3-I and mitochondrial recruitment of phosphorylated PTEN-induced kinase. Therefore, exercise attenuates the transition from NAFL to NASH, improves biochemical and histological parameters of NAFLD, and impedes the progression of fibrosis and tumorigenesis associated with enhanced activation of AMPK signaling and favors liver autophagy. Our work supports the benefits of exercise independently of dietary changes.

Beneficial Effects of Insect Extracts on Nonalcoholic Fatty Liver Disease

It is well known that nonalcoholic fatty liver disease (NAFLD) is a common disease worldwide because of unhealthy changes in dietary habits. In this study, we determined the effects of Tenebrio molitor Linnaeus, 1758 extract (TML) and Allomyrina dichotoma Linnaeus, 1771 larvae extract (ADL) in cellular and animal models. In vitro, TML and ADL treatments did not cause cytotoxicity, but attenuated the accumulation of lipid in HepG2 cells induced by free fatty acids. In vivo, mice were orally treated with TML and ADL for 10 weeks during high-fat diet feeding. TML and ADL administration significantly reduced the weight of body, liver tissue, and adipose tissue. Serum lipid profiles, hepatic functional parameters, and glucose levels were ameliorated by TML and ADL. Moreover, TML and ADL suppressed increased lipogenesis and inflammation-related makers, and improved antioxidant enzyme activity. In liver tissue, the decreased lipid accumulation by administration of TML and ADL was observed using Oil Red O and Hematoxylin and Eosin staining. Therefore, we suggest that TML and ADL may be having a therapeutic potential and is used to develop a therapeutic agent for NAFLD.

Lifestyle Modification Leads to Spatially Variable Reduction in Hepatic Steatosis in Potential Living Liver Donors

The spatial variability of hepatic fat reduction in potential living liver donors with hepatic steatosis (HS) who undergo lifestyle modification has not been investigated. Here, we aimed to examine the intrasegmental and intersegmental variability of changes in liver attenuation on computed tomography (CT) in potential living liver donors with HS after diet modification and exercise. A total of 87 living liver donor candidates (30.5 ± 7.0 years; 74 males) with biopsy-proven macrovesicular fat (MaF) ≥10% were included. All underwent diet modification and exercise to improve HS, baseline and follow-up unenhanced CT scans, and liver biopsies. Attenuation and its variability (mean and standard deviation, respectively, in Hounsfield units) in segmental, lobar, superficial, deep, and whole areas of the liver were measured across 32 different regions of interest on both baseline and follow-up CT. At baseline, the right lobe and superficial areas of liver showed significantly lower and more variable attenuation than left lobe and deep areas. Greater variability was noted in patients with more severe HS. Mean interval changes in liver attenuation and variability before and after diet modification and exercise were 13.7 (range, -10.6 to 46.2) and 4.7 (1.6-10.6), respectively. The mean interval change in liver attenuation was significantly higher in the right lobe than in the left (14.7 versus 12.7; P < 0.001), and in superficial areas than in deep areas (14.0 versus 13.4; P = 0.02). Greater variability and larger interval changes in liver attenuation were noted in those who responded (≥20% decrease in MaF) to diet modification and exercise than in those who did not. In conclusion, potential living liver donors with HS show significant intrasegmental and intersegmental variability in hepatic fat reduction on CT before and after diet modification and exercise.

Treatment of non-alcoholic fatty liver disease - Current perspectives

Therapeutics aimed at treating non-alcoholic fatty liver disease (NAFLD) target the pathogenic process from deranged metabolism leading to steatosis to cell stress and death, leading to a cascade of inflammation and fibrosis, ultimately culminating into cirrhosis. The development of drugs for management of NAFLD has bloomed over the past decade, although at present there is no approved pharmacological agent for its management. Not all patients with the disease progress to cirrhosis and decompensation; hence, treatment specifically is provided for those with a high risk of progression such as those with biopsy-proven steatohepatitis or fibrosis. Along with disease-specific management, all patients must receive therapies directed at risk factors such as dyslipidemia, insulin resistance, type 2 diabetes mellitus and obesity. Comorbidities such as cardiovascular disease, sleep apnoea and chronic kidney disease need management. A current perspective on the therapeutic options is detailed in this review.

Therapeutics administered during ex vivo liver machine perfusion: An overview

Although the use of extended criteria donors has increased the pool of available livers for transplant, it has also introduced the need to develop improved methods of protection against ischemia-reperfusion injury (IRI), as these "marginal" organs are particularly vulnerable to IRI during the process of procurement, preservation, surgery, and post-transplantation. In this review, we explore the current basic science research investigating therapeutics administered during ex vivo liver machine perfusion aimed at mitigating the effects of IRI in the liver transplantation process. These various categories of therapeutics are utilized during the perfusion process and include invoking the RNA interference pathway, utilizing defatting cocktails, and administering classes of agents such as vasodilators, anti-inflammatory drugs, human liver stem cell-derived extracellular vesicles, and δ-opioid agonists in order to reduce the damage of IRI. Ex vivo machine perfusion is an attractive alternative to static cold storage due to its ability to continuously perfuse the organ, effectively deliver substrates and oxygen required for cellular metabolism, therapeutically administer pharmacological or cytoprotective agents, and continuously monitor organ viability during perfusion. The use of administered therapeutics during machine liver perfusion has demonstrated promising results in basic science studies. While novel therapeutic approaches to combat IRI are being developed through basic science research, their use in clinical medicine and treatment in patients for liver transplantation has yet to be explored.