Effect of bariatric surgery on nonalcoholic fatty liver disease: systematic review and meta-analysis

Outcome of liver transplantation in patients with prior bariatric surgery

Nonalcoholic fatty liver disease is becoming the leading cause of disease resulting in liver transplantation (LT). As a result of this trend, more LT candidates are presenting with prior history of bariatric surgery (BS). Over the last decade, 960 patients underwent LT at our institution; 11 (1.1%) had prior BS. The most common type of BS was Roux-en-Y gastric bypass (n = 9) with 1 sleeve gastrectomy and 1 jejunoileal bypass. A total of 9 patients underwent LT alone, and 2 underwent simultaneous liver-kidney transplantation. The most common indication for LT was nonalcoholic steatohepatitis (n = 10) with 5 having additional diagnosis of alcoholic liver disease. The 30-day reoperation rate was 36.4% (n = 4); indications were bile duct repair (n = 3) and wound repair (n = 1). In the first 6 months after LT, biliary complications were seen in 54.5% (n = 6) of the patients. Both patient and graft survival rates at 1 and 2 years were 81.8% (n = 9) and 72.7% (n = 8), respectively. A total of 8 patients (72.7%) had indications for liver biopsy after LT; significant macrovesicular steatosis was found in 2 (18.2%). In patients with a history of alcohol consumption, 2 (40.0%) relapsed after LT. Two patients (18.2%) had a history of diet-controlled diabetes before LT; 1 of these patients became insulin dependent after LT. Mean body mass index (BMI) at LT was 31.0 ± 5.7 kg/m² . Mean BMI at 1, 6, and 12 months after LT was 28.3 ± 5.8, 28.0 ± 3.2, and 31.0 ± 6.6 kg/m² , respectively. Mean preoperative albumin was 2.6 ± 0.6 mg/dL. Patients showed improvement in albumin after LT, with mean albumin of 2.7 ± 0.6 and 3.2 ± 0.5 mg/dL at 1 and 3 months, respectively. The liver profile was stable after LT, with mean aspartate aminotransferase of 32.9 ± 18.4 and 26.6 ± 19.8 IU/L and alanine aminotransferase of 28.0 ± 17.5 and 30.2 ± 17.0 IU/L at 6 and 12 months, respectively. In conclusion, outcomes of LT patients with prior BS are comparable with other transplant recipients with regards to patient and graft survival and post-LT complication rates. Liver Transplantation 23 1415-1421 2017 AASLD.

Impact of bariatric surgery on outcomes of patients with nonalcoholic fatty liver disease: a nationwide inpatient sample analysis, 2004-2012

BACKGROUND

Bariatric surgery in eligible morbidly obese individuals may improve liver steatosis, inflammation, and fibrosis; however, population-based data on the clinical benefits of bariatric surgery in patients with nonalcoholic fatty liver disease (NAFLD) are lacking.

OBJECTIVES

To assess the relationship between bariatric surgery and clinical outcomes in hospitalized patients with NAFLD.

SETTING

United States inpatient care database.

METHODS

The Nationwide Inpatient Sample database was queried from 2004 to 2012 with co-diagnoses of NAFLD and morbid obesity. Hospitalizations with a history of prior bariatric surgery (Roux-en-Y gastric bypass, gastric band, and sleeve gastrectomy) were also identified. The primary outcome was in-hospital mortality. Secondary outcomes included cirrhosis, myocardial infarction, stroke, and renal failure. Poisson regression was used to derive adjusted incidence risk ratios for clinical outcomes in patients with prior bariatric surgery compared with those without bariatric surgery.

RESULTS

Among 45,462 patients with a discharge diagnosis of NAFLD and morbid obesity, 18,618 patients (41.0%) had prior bariatric surgery. There was a downward trend in bariatric surgery procedures (percent annual change of -5.94% from 2004 to 2012). In a multivariable analysis, prior bariatric surgery was associated with decreased inpatient mortality compared with no bariatric surgery (incidence risk ratios = .08; 95% confidence interval, .03-.20, P<.001). Prior bariatric surgery was also associated with decreased incidence risk ratios for cirrhosis, myocardial infarction, stroke, and renal failure (all P<.001).

CONCLUSIONS

Prior bariatric surgery is associated with decreased in-hospital morbidity and mortality in morbidly obese NAFLD patients. Despite this, the proportion of NAFLD patients with bariatric surgery has declined from 2004 to 2012.

What Is the Evidence for Paediatric/Adolescent Bariatric Surgery?

PURPOSE OF REVIEW

In spite of the increasing prevalence of severe and complex obesity in children, surgery as a potential management option is still not widely accepted. The purpose of this review is to examine the evidence for surgical options in the severely obese paediatric population. Increasing evidence supports early rather than later use of bariatric surgery in the treatment of extreme obesity.

RECENT FINDINGS

Prior to 2007, the feasibility and safety of surgery have been reported by predominantly small, sporadic single-centre retrospective case series. Increasing long-term data is now emerging due to the formation of multi-centre prospective national consortiums with two large, prospective long-term outcome studies published within the last year aiding our understanding of the efficacy and safety of bariatric surgery within the adolescent population. It is increasingly clear that adolescent bariatric surgery outcomes are comparable to adults, with similar sustainable weight loss, resolution of co-morbidities and complication rates. However, these studies are solely from dedicated specialist adolescent centres and results may not be reproducible if not performed in regulated environments with specialist multi-disciplinary teams.

The role of bariatric surgery in nonalcoholic fatty liver disease and nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) affects between 25% and 33% of the population, is more common in obese individuals, and is the most common cause of chronic liver disease in the United States. However, despite rising prevalence, effective treatments remain limited. Areas covered: We performed a literature search across multiple databases (Pubmed, Medline, etc.) to identify significant original research and review articles to provide an up-to-date and concise overview of disease pathogenesis and diagnostic evaluation and to expand on available treatment options with a specific focus on the potential role of bariatric surgery. Here we provide the most comprehensive review of bariatric surgery for the management of NAFLD, noting benefits from different procedures and multiple reports showing improvements in steatosis, inflammation and fibrosis over the duration of follow-up. Expert commentary: The morbidity of NAFLD is significant as it may become the most common indication for liver transplantation within the next 5 years. In addition to known benefits of weight loss and diabetes resolution, bariatric surgery has the potential to halt and reverse disease progression and future controlled trials should be performed to further define its benefit in the treatment of NAFLD in morbidly obese patients.

Bariatric surgery in individuals with liver cirrhosis: A narrative review

Introduction:

Bariatric surgery has become the gold standard treatment for morbid obesity, but there is no consensus regarding its safety and efficacy among individuals with chronic liver diseases.

Objective:

To critically evaluate the existing evidence on literature about bariatric surgery in individuals with liver cirrhosis.

Method:

Narrative review performed by means of an online search in the MEDLINE and LILACS databases.

Results:

Bariatric surgery is safe and effective in individuals with chronic liver disease without clinical decompensation or significant portal hypertension. Individuals with severe liver function impairment present significantly higher surgical morbidity and mortality. Among candidates to liver transplantation, surgery may be performed before, after and even during transplantation, and there is a predominant trend to perform it after. Vertical sleeve gastrectomy seems to be the most adequate technique in this group of subjects.

Conclusion:

Bariatric surgery is safe and effective in individuals with compensated cirrhosis without significant portal hypertension, but presents higher morbidity. Among candidates to liver transplantation and/or individuals with severe portal hypertension, morbidity and mortality are significantly higher.

Antidiabetic Effects of Gastric Banding Surgery in Morbidly Obese Patients with Type 2 Diabetes Mellitus

This study was performed to investigate the effect of gastric banding surgery on the improvement of glycated hemoglobin (HbA_1c) of morbidly obese (MO) patients with type 2 diabetes mellitus (T2DM) with the consideration that obesity was associated with insulin resistance and T2DM. We retrospectively reviewed the medical records of 38 MO with T2DM patients and 50 MO patients. Pre-surgery and post-surgery data were analyzed a year later. The medical data from these patients, including sex, age, height, weight, body composition, HbA_1c, triglyceride, total cholesterol, aspartate transaminase (AST), and alanine transaminase (ALT) were measured. There were significant reductions of body weight and body mass index (BMI), body fat, body fat percentage, waist-hip ratio, visceral fat, and obesity in each group before and after gastric banding surgery. Results of AST, ALT, and HbA_1c had significant reductions in each group. For HbA_1c, treatment rate was 71% in the MO group with T2DM with significant reduction of 22.8%. It is thought that a gastric banding surgery is one of the breakthrough methods not only for weight loss but also for the prevention of complication of the obese patients with T2DM. Thus, gastric banding surgery could be effective in controlling HbA_1c in obese patients with type 2 diabetes mellitus.

Current management of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is characterized by hepatic accumulation of lipid in patients who do not consume alcohol in amounts generally considered harmful to the liver. NAFLD is becoming a major liver disease in Eastern countries and it is related to insulin resistance and metabolic syndrome. Treatment has focused on improving insulin sensitivity, protecting the liver from oxidative stress, decreasing obesity and improving diabetes mellitus, dyslipidemia, hepatic inflammation and fibrosis. Lifestyle modification involving diet and enhanced physical activity associated with the treatment of underlying metabolic are the main stain in the current management of NAFLD. Insulin-sensitizing agents and antioxidants, especially thiazolidinediones and vitamin E, seem to be the most promising pharmacologic treatment for non-alcoholic steatohepatitis, but further long-term multicenter studies to assess safety are recommended.

Gastric bypass surgery mimetic approaches

Gastric bypass surgery is effectively a polypharmacological approach for treatment of obesity, type 2 diabetes and nonalcoholic steatohepatitis (NASH). The gastric bypass mimetic approaches reviewed are fixed-dose combinatorial pharmacological approaches. There are two key concepts incorporated into these gastric bypass surgery mimetic approaches. The first key concept is that the combination of glucagon-like peptide 1 (GLP-1) and fibroblast growth factor 21 (FGF21) is essential for success of any gastric bypass surgery mimetic approach. This combination affords the potential for durable weight loss, glycemic control and reduction in liver lipids. The second key concept is that a fixed-dose combination approach is preferred over post-approval combination of the individual components because the individual components alone often lack sufficient efficacy for development.

Liver failure after long-limb gastric bypass

Liver failure is reported with increasing frequency in patients who underwent bariatric surgery for morbid obesity. In most cases, liver transplantation is the only possible treatment to avoid fatal outcome. Although most cases are observed after older bariatric surgery techniques characterized by high malabsorption rates, we report on a 38-year-old woman who developed liver failure seven months after long-limb gastric bypass.

Non-alcoholic fatty liver disease: An update with special focus on the role of gut microbiota

Non-alcoholic fatty liver disease (NAFLD) is a significant global health burden in children, adolescents and adults with substantial rise in prevalence over the last decades. Accumulating data from manifold studies support the idea of NAFLD as a hepatic manifestation of metabolic syndrome, being rather a systemic metabolic disease than a liver confined pathology. Emerging data support that the gut microbiome represents a significant environmental factor contributing to NAFLD development and progression. Apart from other regimens, probiotics may have a positive role in the management of NAFLD through a plethora of possible mechanisms. The current review focuses on the NAFLD multifactorial pathogenesis, including mainly the role of intestinal microbiome and all relevant issues are raised. Furthermore, the clinical manifestations and appropriate diagnostic approach of the disease are discussed, with all possible therapeutic measures that can be taken, also including the potential beneficial effect of probiotics.

Nonalcoholic fatty liver disease and bariatric surgery: a comprehensive review

CONTEXT AND OBJECTIVE:

Nonalcoholic fatty liver disease (NAFLD) has been increasingly diagnosed worldwide and is now recognized as a source of public health concern. It comprises a wide spectrum of histological features that range from simple steatosis to severe forms of fibrosis, steatohepatitis and even cirrhosis. The impact of bariatric surgery on the course of NAFLD in individuals with obesity has been extensively studied.

DESIGN AND SETTING:

Narrative review; public university hospital.

METHODS:

A comprehensive review was conducted based on an online search on the electronic databases MEDLINE and LILACS using the MeSH terms "fatty liver" and "bariatric surgery".

RESULTS:

The exact mechanisms that lead to improvement in NAFLD following bariatric surgery are not completely understood. Since Roux-en-Y gastric bypass (RYGB) is the bariatric surgical procedure most performed worldwide, it is also the one from which the effects on NAFLD have been most studied, although there is also consistent evidence regarding the effects from gastric banding, sleeve gastrectomy and biliopancreatic diversions.

CONCLUSION:

According to the currently available evidence, bariatric surgery leads to significant improvement in NAFLD. Further research, especially by means of randomized controlled trials enrolling larger cohorts of individuals, is needed to determine the optimal procedure for this group of subjects.

Features of nonalcoholic steatohepatitis in severely obese children and adolescents undergoing sleeve gastrectomy

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is an underrecognized co-morbidity of obesity. The characteristic features and severity of NAFLD in severe childhood obesity remain unknown.

OBJECTIVES

To investigate features of NAFLD in obese children and identify predictors of significant disease.

SETTING

Academic center with a standardized pathway for pediatric bariatric surgery and a dedicated multidisciplinary team.

DESIGN

This is a baseline cross-sectional analysis for a data set obtained from a prospective clinical outcome study that included severely obese children (≤14 yr of age) and adolescents (14-21 yr of age) who underwent laparoscopic sleeve gastrectomy between March 2008 and March 2015. Patients with syndromic obesity, history of alcohol intake, parenteral nutrition, liver disease, intake of medications that may affect NAFLD and weight, and insufficient tissue biopsy were excluded. Prevalence and features of nonalcoholic steatohepatitis (NASH) and clinically significant liver fibrosis in different pediatric age groups and noninvasive predictors in severe childhood obesity were evaluated.

RESULTS

The 296 patients in the study group (1:1 sex distribution) had a mean body mass index and age of 48.4±9.8 kg/m² and 14.5±3.6 years, respectively. According to histopathology assessment, 225 (76%) patients had NAFLD, of whom 118 patients (39.9% of the total cohort) had NASH. Additionally, 110 (37.2%) had clinically significant (stage 2+) fibrosis and 256 (86.5%) had portal inflammation. Those with NASH were younger than those without NASH (P = .02; prevalence of NASH in children aged≤10 yr = 64.9%) and were more likely to be male (P = .003). Of children aged≤10 years, 60% had clinically significant fibrosis compared with 32% of older patients (P = .03). High-density lipoproteins, triglycerides, glycated hemoglobin, alanine transaminase, and systolic and diastolic blood pressure levels were most predictive of fibrosis. For NASH, triglycerides, homeostatic model assessment of insulin resistance, glycated hemoglobin, alkaline phosphatase, aspartate transaminase, and alanine transaminase were most predictive.

CONCLUSIONS

In our setting, 65% of severely obese young children had NASH, and 60% had clinically significant liver fibrosis. Young age, male sex, and features of metabolic syndrome were significantly associated with NASH and liver fibrosis in severely obese pediatric patients.

Bariatric surgery for nonalcoholic steatohepatitis: A clinical and cost-effectiveness analysis

Nonalcoholic steatohepatitis (NASH) affects 2%-3% of the US population and is expected to become the leading indication for liver transplantation in the next decade. Bariatric surgery may be an effective but expensive treatment for NASH. Using a state-transition model, our analysis assessed the effectiveness and cost-effectiveness of surgery to manage NASH. We simulated the benefits and harms of laparoscopic Roux-en-Y gastric bypass surgery in patients defined by weight class (overweight, mild obesity, moderate obesity, and severe obesity) and fibrosis stage (F0-F3). Comparators included intensive lifestyle intervention (ILI) and no treatment. Quality-adjusted life years (QALYs), costs, and incremental cost-effectiveness ratios were calculated. Our results showed that surgery and ILI in obese patients (with F0-F3) increased QALYs by 0.678-2.152 and 0.452-0.618, respectively, compared with no treatment. Incremental cost-effectiveness ratios for surgery in all F0-F3 patients with mild, moderate, or severe obesity were $48,836/QALY, $24,949/QALY, and $19,222/QALY, respectively. In overweight patients (with F0-F3), surgery increased QALYs by 0.050-0.824 and ILI increased QALYs by 0.031-0.164. In overweight patients, it was cost-effective to reserve treatment only for F3 patients; the incremental cost-effectiveness ratios for providing surgery or ILI only to F3 patients were $30,484/QALY and $25,367/QALY, respectively.

CONCLUSIONS

Surgery was both effective and cost-effective for obese patients with NASH, regardless of fibrosis stage; in overweight patients, surgery increased QALYs for all patients regardless of fibrosis stage, but was cost-effective only for patients with F3 fibrosis; our results highlight the promise of bariatric surgery for treating NASH and underscore the need for clinical trials in this area. (Hepatology 2017;65:1156-1164).

Perspectives on Nonalcoholic Fatty Liver Disease: An Overview of Present and Future Therapies

Nonalcoholic fatty liver disease (NAFLD) represents a major public health epidemic. Pharmacologic therapies for this condition are scarce, but multiple agents with novel mechanisms of action are in development. Here we review the pathophysiology and natural history of NALFD, diagnostic testing and data for currently available treatment strategies. We then turn our attention to promising developmental drugs and their respective trials. As the prevalence of fatty liver disease increases, clinicians will have more tools at hand for management of this condition. We conclude the horizon is bright for patients and doctors who deal with NAFLD.

Nutritional Approaches to Achieve Weight Loss in Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) can range in spectrum from simple hepatic steatosis to nonalcoholic steatohepatitis (NASH), which is characterized by lipotoxicity, hepatocellular ballooning, and inflammation and can progress to cirrhosis. Weight loss is the cornerstone treatment for NAFLD and NASH. Various randomized controlled trials have shown that weight loss of ≥5-10% leads to significant improvements in hepatic steatosis. Diets high in sodium and fructose have been implicated in the pathogenesis of NAFLD. Although some clinical studies suggest that an isocaloric high-fructose diet does not worsen NAFLD, these clinical studies are often short in duration. More recently, the Dietary Approaches to Stop Hypertension diet, a sodium-restricted diet, has been associated with less prevalence of NAFLD and has been shown to improve NAFLD. In addition, the Mediterranean diet has been promising in improving hepatic steatosis, and a larger randomized controlled trial is currently enrolling subjects. For those who are unable to pursue weight loss through dietary approaches, bariatric surgery has been shown to improve hepatic steatosis and steatohepatitis. This method has been variable in improving hepatic fibrosis. In conclusion, weight loss is crucial to the improvement of NAFLD and NASH, and patients should attempt various diets in an attempt to achieve weight loss.

Management of Nonalcoholic Fatty Liver Disease in Patients With Type 2 Diabetes: A Call to Action

Traditionally a disease of hepatologists, nonalcoholic fatty liver disease (NAFLD) has recently become a major concern for a broad spectrum of health care providers. Endocrinologists and those caring for patients with type 2 diabetes mellitus (T2DM) are at center stage, as T2DM appears to worsen the course of NAFLD and the liver disease makes diabetes management more challenging. However, the nature of this relationship remains incompletely understood. Although the increasing prevalence of NAFLD is frequently attributed to the epidemic of obesity and is often oversimplified as the "hepatic manifestation of the metabolic syndrome," it is a much more complex disease process that may also be observed in nonobese individuals and in patients without clinical manifestations of the metabolic syndrome. It carries both metabolic and liver-specific complications that make its approach unique among medical conditions. Diabetes appears to promote the development of nonalcoholic steatohepatitis (NASH), the more severe form of the disease, and increases the risk of cirrhosis and hepatocellular carcinoma. Patients and physicians face many uncertainties, including fragmented information on the natural history of the disease, challenges in the diagnosis of NASH, and few pharmacological agents with proven efficacy. However, recent advances in diagnosis and treatment, combined with the risk of serious consequences from inaction, call for health care providers to be more proactive in the management of patients with T2DM and NASH.

Short- and Long-Term Reproducibility of Intrahepatic Lipid Quantification by 1H-MR Spectroscopy and CT in Obesity

OBJECTIVE

This study aimed to assess short- and long-term reproducibility of intrahepatic lipid (IHL) quantification by proton magnetic resonance spectroscopy (H-MRS) and computed tomography (CT).

METHODS

Sixteen obese subjects underwent H-MRS using a single-voxel point-resolved single-voxel spectroscopy sequence at 3 T and noncontrast single-slice CT of the liver. Measurements were repeated after 6 weeks and 6 months. Clinical parameters (weight, activity, serum lipids) were collected. Short-term (baseline to 6 weeks) and long-term (baseline to 6 months) reproducibility of IHL was assessed by coefficient of variance (CV), SD, and intraclass correlation coefficient (ICC).

RESULTS

Short-term reproducibility and long-term reproducibility of H-MRS were as follows: CV, 5.9% to 18.8%; SD, 0.7 to 1.9; and ICC, 0.998 to 0.995 (95% confidence interval, 0.942-0.999). Short-term reproducibility and long-term reproducibility of CT were as follows: CV, 4.4% to 14.2%; SD, 2.4 to 8.7; and ICC, 0.766 to 0.982 (95% confidence interval, 0.271-0.994). There was no significant change in clinical parameters (P > 0.3).

CONCLUSIONS

Proton magnetic resonance spectroscopy and CT are reproducible methods for short- and long-term quantification of IHL content. Our results can guide sample size calculations for interventional and longitudinal studies.

What is the role of bariatric surgery in the management of obesity?

Diet, exercise, cognitive behavioral therapy and pharmacotherapy are some of the means of assisting patients to lose weight, with bariatric surgery being the most effective. Over the last two decades, the increased awareness of the systemic benefits of bariatric surgery, as well as the improved safety and the wider use of the laparoscopic approach, has made bariatric surgery flourish. In the United Kingdom, the adjustable gastric band (10%), vertical sleeve gastrectomy (37%) and Roux-en-Y gastric bypass (45%) are the three most common procedures. Obesity-associated mortality and co-morbidities such as type 2 diabetes, hypertension, dyslipidemia, obstructive sleep apnea, renal dysfunction and depression improve significantly with bariatric surgery. The mechanisms of weight loss extend beyond restriction and malabsorption and include changes in hunger and satiety, food preferences, and possibly energy expenditure. Despite its safety and efficacy, bariatric surgery is underutilized as less than 1% of adults with obesity receive it. In view of the evolution of obesity into a global threat, access to bariatric surgery should be increased, whilst developing safer and less invasive weight loss treatments.

Derivation and validation of a scoring system for predicting nonalcoholic steatohepatitis in Taiwanese patients with severe obesity

BACKGROUND

Nonalcoholic steatohepatitis (NASH) is common in severely obese Asians and may progress to advanced liver disease. Although invasive, liver biopsy is the gold standard for NASH diagnosis. Scoring systems for predicting NASH in obese Asians are scarce.

OBJECTIVES

To develop and validate a scoring system to predict NASH in Taiwanese patients with severe obesity.

SETTING

University hospital, Taiwan.

METHODS

Preoperative clinical and laboratory data were obtained from 180 severely obese patients who underwent bariatric surgery. NASH was evaluated by liver histopathology. Patients were divided into 2 groups: a derivation cohort (n = 120) and a validation cohort (n = 60).

RESULTS

Of the 180 patients, 91 (50.6%) had NASH. Multivariate analysis identified body mass index (BMI), alanine aminotransferase (ALT), and triglyceride as independent predictors for NASH in the derivation group. A weighted sum of the score was: [(1 for presence of 45 kg/m² ≧ BMI>40 kg/m²) or (2 for presence of BMI>45 kg/m²)+(2 for presence of ALT>40 IU/L)+(1 for presence of triglyceride>140 mg/L)]. The area under the receiver operating characteristic curve of this model was .80 and .82 in derivation and validation cohort, respectively. Patients were further divided into low- and high-risk for NASH by using a cutoff score of 3. Diagnostic accuracy was 74% and 80% in derivation and validation cohorts, respectively.

CONCLUSION

We developed and subsequently validated a simple clinical scoring system incorporating BMI, ALT, and triglyceride to predict NASH in Taiwanese patients with severe obesity.

Pediatric liver diseases: current challenges and future perspectives

Chronic liver diseases in children represent a rising problem with significant effects on public health. In fact, several pediatric liver diseases are precursors of adult chronic hepatopathies, cirrhosis and hepatocellular carcinoma. The prevalence of liver diseases in children is unknown. In the USA, every year, 15,000 children are hospitalized for liver diseases, but these disorders continue to be under-recognized or diagnosed late. The main reason is due to the frequent absence of symptoms in the vast majority of liver diseases, especially in the early stages. In the last few decades several advances have been made in understanding the pathogenesis of liver diseases, permitting the discovery of new therapeutic targets to treat liver diseases, thus improving the natural history of these disorders. In this article we discuss the most recent advances in the understanding of the pathogenesis, diagnosis and treatment of the most frequent pediatric liver diseases.

Non-alcoholic fatty liver disease in 2016

INTRODUCTION

Non-alcoholic fatty liver disease is the commonest cause of liver disease worldwide, and is rapidly becoming the leading indication for liver transplantation.

SOURCES OF DATA

Original articles, reviews and meta-analyses, guidelines.

AREAS OF AGREEMENT

NAFLD strongly correlates with obesity and insulin resistance; currently, the best management strategy is weight loss and treatment of the metabolic syndrome.

AREAS OF CONTROVERSY

Recent data suggest that the presence of fibrosis and not non-alcoholic steatohepatitis (NASH) is the predictor of clinical outcome.

GROWING POINTS

Many phase 2 and 3 trials are underway. Drugs hoped to be effective are obeticholic acid, elafibranor, glucagon-like peptide-1 analogues and CCR2/5 inhibitors.

AREAS TIMELY FOR DEVELOPING RESEARCH

Improved understanding of the pathophysiology of NAFLD should help us identify which patients progress to significant liver disease and to develop therapies to target this population.

Pathogenesis and novel treatment options for non-alcoholic steatohepatitis

Non-alcoholic fatty liver disease affects 20-40% of the population. Its active form, non-alcoholic steatohepatitis (NASH), is characterised by hepatocyte injury, liver inflammation, and progression of fibrosis, and has emerged as one of the most important causes of liver failure and hepatocellular carcinoma. Weight reduction of 10% by dietary restriction and regular exercise is sufficient to reverse NASH in most patients, but in practice this reduction is often not achieved. Available drugs such as vitamin E, pioglitazone, and pentoxifylline have borderline efficacy, but are limited by potential side-effects and toxicities, and do not improve liver fibrosis. However, basic and translational research has improved our understanding of the pathophysiology of NASH, thereby identifying several promising new treatment targets. Several drugs are in phase 2 and 3 development and could enter clinical practice in the near future. In this Review, we discuss the pathogenesis, treatment evaluation, existing therapies, and potential new treatments for NASH.

The role of bariatric surgery in the management of nonalcoholic fatty liver disease and metabolic syndrome

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. NAFLD is strongly associated with obesity and metabolic syndrome (MetS). Current treatment of NAFLD is based on weight reduction. Bariatric surgery is the most effective treatment for morbid obesity and its associated metabolic comorbidities. There is evidence indicating that bariatric surgery improves histological and biochemical parameters of NAFLD, but currently is not considered a treatment option for NAFLD. The aim of this work is to review the evidence for the effects of bariatric surgery on NAFLD and the MetS. We found that insulin resistance, alterations in glucose metabolism, hypertension, plasma lipids, transaminases, liver steatosis, steatohepatitis and fibrosis improve after bariatric surgery. Weight loss and improvement of NAFLD are greater after RYGB than after other interventions. These findings were obtained from retrospective or cohort studies. There are no studies designed to evaluate liver-specific mortality, liver transplantation, or quality of life. Patients with indications for bariatric surgery will benefit from the improvements in the MetS and NAFLD.

Non-alcoholic fatty liver disease and dyslipidemia: An update

Non-alcoholic fatty liver (NAFLD) is the most common liver disease worldwide, progressing from simple steatosis to necroinflammation and fibrosis (leading to non-alcoholic steatohepatitis, NASH), and in some cases to cirrhosis and hepatocellular carcinoma. Inflammation, oxidative stress and insulin resistance are involved in NAFLD development and progression. NAFLD has been associated with several cardiovascular (CV) risk factors including obesity, dyslipidemia, hyperglycemia, hypertension and smoking. NAFLD is also characterized by atherogenic dyslipidemia, postprandial lipemia and high-density lipoprotein (HDL) dysfunction. Most importantly, NAFLD patients have an increased risk for both liver and CV disease (CVD) morbidity and mortality. In this narrative review, the associations between NAFLD, dyslipidemia and vascular disease in NAFLD patients are discussed. NAFLD treatment is also reviewed with a focus on lipid-lowering drugs. Finally, future perspectives in terms of both NAFLD diagnostic biomarkers and therapeutic targets are considered.

Nonalcoholic Fatty Liver Disease and Liver Transplantation

Nonalcoholic fatty liver disease (NAFLD) is prevalent in the general population and a growing indication for liver transplant. Longer wait times and challenges with pretransplant survivorship are expected, underscoring the need for improved management of attendant comorbidities. Recognition with potential modification of obesity, sarcopenia, chronic kidney disease, and cardiovascular disease in patients with NAFLD may have important implications in the pretransplant and posttransplant periods. Although patients with NAFLD have generally favorable postoperative outcomes, they are at risk for developing recurrent disease in their allograft, driving the need for pharmacotherapies and dietary innovations appropriate for use in the posttransplant period.

Medical and Surgical Treatment Options for Nonalcoholic Steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of liver disease in the USA with a growing prevalence worldwide. Nonalcoholic steatohepatitis (NASH), progressive form of NAFLD, can lead to the development of cirrhosis, hepatocellular carcinoma, and the need for liver transplantation. Treatment of NASH may decrease the risk of progressive disease. Treatment for NAFLD should center around weight loss and exercise. Pharmacotherapy with vitamin E and pioglitazone should be considered for those with NASH, especially those with fibrosis. Weight loss surgery is also an effective treatment for NASH in individuals with other indications for surgery. In this review, we will discuss the currently available therapies for NASH including lifestyle, pharmacologic, and surgical options.

The Metabolic Syndrome and Its Influence on Nonalcoholic Steatohepatitis

Nonalcoholic steatohepatitis (NASH) and the metabolic syndrome (MetS) are highly prevalent in the Western population. Their pathogenesis is closely linked to insulin resistance, which serves as a therapeutic target for the management of these conditions. This review article reviews the research supporting the influence of MetS on NASH and includes studies supporting their similar epidemiology, pathogenesis, and treatment.

Republished: Non-alcoholic fatty liver disease: a practical approach to treatment

Non-alcoholic fatty liver disease (NAFLD) affects up to a third of the population in many developed countries. Between 10% and 30% of patients with NAFLD have non-alcoholic steatohepatitis (NASH) that can progress to cirrhosis. There are metabolic risk factors common to both NAFLD and cardiovascular disease, so patients with NASH have an increased risk of liver-related and cardiovascular death. Management of patients with NAFLD depends largely on the stage of disease, emphasising the importance of careful risk stratification. There are four main areas to focus on when thinking about management strategies in NAFLD: lifestyle modification, targeting the components of the metabolic syndrome, liver-directed pharmacotherapy for high risk patients and managing the complications of cirrhosis.

Non-Alcoholic Fatty Liver Disease (NAFLD): The Search for a Cure

An alarming rise of obesity and, along with it, non-alcoholic fatty liver disease (NAFLD), has been observed in the USA and the rest of the world. NAFLD, the most common cause of chronic liver disease in many developed countries, is not always a benign disorder and considering its growing nature, will have a serious impact on healthcare systems worldwide. The search continues for a suitable therapy for this disorder; the therapy ideally needs to be safe, effective, and affordable. The biggest hurdle in the process of developing such a therapy is our lack of a complete understanding of the pathogenesis of the disease.

Influence of Roux-en-Y gastric bypass on plasma bile acid profiles: a comparative study between rats, pigs and humans

BACKGROUND

Roux-en-Y gastric bypass (RYGBP) is the most widely used bariatric surgery procedure, which induces profound metabolic and physiological effects, such as substantial improvements in obesity, type 2 diabetes and their comorbidities. Increasing evidence identifies bile acids (BAs) as signaling molecules that contribute to the metabolic improvement after RYGBP. However, how and to what extent BAs mediate the metabolic effects of RYGBP still remains unclear and requires mechanism of action studies using preclinical models. In this study, we compared plasma BA profiles before and after RYGBP in two animal models, rats and pigs, with humans to evaluate their translational potential.

METHODS

Plasma BAs were profiled in rats, pigs and humans by liquid chromatography coupled with tandem mass spectrometry before and after RYGBP.

RESULTS

RYGBP increased baseline plasma total BA concentrations in humans and in the two animal models to a similar extent (∼3-fold increase), despite differences in presurgery BA levels and profiles between the models. However, qualitatively, RYGBP differently affected individual plasma BA species, with similar increases in some free species (cholic acid (CA), chenodeoxycholic acid (CDCA) and deoxycholic acid (DCA)), different increases in glyco-conjugated species depending on the model and globally no increase in tauro-conjugated species whatever the model.

CONCLUSIONS

The tested animal models share similar quantitative RYGBP-induced increases in peripheral blood BAs as humans, which render them useful for mechanistic studies. However, they also present qualitative differences in BA profiles, which may result in different signaling responses. Such differences need to be taken into account when translating results to humans.

Bariatric Surgery and Liver Cancer in a Consortium of Academic Medical Centers

Obesity is implicated as an important factor in the rising incidence of liver cancer in the USA. Bariatric surgery is increasingly used for treating morbid obesity and comorbidities. Using administrative data from UHC, a consortium of academic medical centers in the USA, we compared the prevalence of liver cancer among admissions with and without a history of bariatric surgery within a 3-year period. Admissions with a history of bariatric surgery had a 61 % lower prevalence of liver cancer compared to those without a history of bariatric surgery (prevalence ratio 0.39, 95 % confidence interval 0.35-0.44), and these inverse associations persisted within strata of sex, race, and ethnicity. This hospital administrative record-based analysis suggests that bariatric surgery could play a role in liver cancer prevention.

A Comprehensive Updated Review of Pharmaceutical and Nonpharmaceutical Treatment for NAFLD

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease in the western world with prevalence of 20–33%. NAFLD comprises a pathological spectrum. Nonalcoholic fatty liver (NAFL) is at one end and consists of simple hepatic steatosis. On the contrary, nonalcoholic steatohepatitis (NASH) consists of steatosis, inflammation, and ballooning degeneration and can progress to cirrhosis. Despite the rising incidence, definitive treatment for NAFLD, specifically NASH, has not yet been established. Lifestyle modification with dietary changes combined with regular aerobic exercise, along with multidisciplinary approach including cognitive behavior therapy, has been shown to be an effective therapeutic option, even without a significant weight loss. Pioglitazone and vitamin E have shown to be most effective in NASH patients. Surgery and weight loss medication are effective means of weight loss but can potentially worsen NASH related fibrosis. Other agents such as n-3 polyunsaturated fatty acids, probiotics, and pentoxifylline along with herbal agent such as milk thistle as well as daily intake of coffee have shown potential benefits, but further well organized studies are definitely warranted. This review focuses on the available evidence on pharmaceutical and nonpharmaceutical therapy in the treatment and the prevention of NAFLD, primarily NASH.

Fatty liver disease and obesity in youth

PURPOSE OF REVIEW

The purpose of this short review is to summarize recent developments in the understanding of pediatric nonalcoholic fatty liver disease (NAFLD), focusing on novel findings in pathogenetic mechanisms and the therapeutic armamentarium.

RECENT FINDINGS

As a result of the increasing prevalence of pediatric obesity, NAFLD has rapidly become the most common cause of chronic hepatopathies in children. Lifestyle modification and diet remain the mainstay of treatment of pediatric obesity and NAFLD, but with disappointing results because of the difficulty in obtaining sustained long-term results. Considering the risk of progression of liver damage to cirrhosis and end-stage liver disease, in the last decades scientific research in this field has been directed to the identification of pathogenetic mechanisms and possible therapeutic strategies for NAFLD.

SUMMARY

We describe the therapeutic options for the management of pediatric NAFLD, focusing on emerging alternative strategies, including surgical approaches and new drugs directed against novel potential molecular targets.

Nonalcoholic Fatty Liver Disease in Latinos

Nonalcoholic fatty liver disease (NAFLD) is a serious public health concern that affects almost one third of the US population. The prevalence of NAFLD varies among ethnic/racial groups, with the Latin American population being affected disproportionately. The severity of NAFLD also may be greater in the Latino population. The increased prevalence and severity of NAFLD in Latino Americans likely is related to the interplay between issues such as genetic factors, access to health care, or the prevalence of chronic diseases such as metabolic syndrome or diabetes. In this review, we summarize the current literature on the prevalence and risk factors of NAFLD that are seen to be more common in the Latino population in the United States. Finally, we discuss available treatment options, medical and surgical, that are available for NAFLD and how they affect the Latino population. Health care providers need to address modifiable risk factors that impact the natural history as well as treatment outcomes for NAFLD among Latinos. Additional efforts are needed to improve awareness and health care utilization for Latinos.

Influence of type 2 diabetes mellitus on liver histology among morbidly obese individuals. A cross-sectional study

CONTEXT AND OBJECTIVE

Nonalcoholic fatty liver disease (NAFLD) has become a public health concern. It encompasses a wide spectrum of histological abnormalities and has close relationships with insulin resistance and type 2 diabetes mellitus (T2DM). This study sought to compare the histological alterations observed in morbidly obese individuals with and without T2DM who underwent Roux-en-Y gastric bypass.

DESIGN AND SETTING

Cross-sectional study in a tertiary-level public hospital.

METHODS

This was a cross-sectional study on 197 individuals who underwent gastric bypass surgery between 2011 and 2013. NAFLD was assessed through liver biopsies. T2DM was diagnosed through the International Diabetes Federation criteria.

RESULTS

Non-diabetics presented significantly more biopsies without any histological abnormalities, regarding steatosis (42.6% versus 25.5%; P = 0.0400), fibrosis (60.6% versus 36.2%; P = 0.0042) and steatohepatitis (27.3% versus 12.8%; P = 0.0495), while diabetics presented significantly higher frequency of moderate forms of steatosis (36.2% versus 20%; P = 0.0307) and fibrosis (23.4% versus 4%; P = 0.0002).

DISCUSSION

T2DM was associated with more advanced forms of NAFLD within the population studied. NAFLD has previously been correlated with severe forms of heart disease.

CONCLUSION

Screening for and early detecting of NAFLD in high-risk populations are important for avoiding further development of severe forms and the need for liver transplantation.

Effect of telmisartan on histological activity and fibrosis of non-alcoholic steatohepatitis: A 1-year randomized control trial

BACKGROUND/AIM

Telmisartan can attenuate two hit pathogenesis of non-alcoholic steatohepatitis (NASH). This study aimed to observe the effect of Telmisartan on non-alcoholic fatty liver disease (NAFLD) activity score (NAS) and fibrosis score in NASH patients.

PATIENTS AND METHODS

A total of 50 NASH patients were randomized; 35 of group 1 were treated with Telmisartan 40/80 mg once daily with life style modification (TL) and 15 of group 2 underwent only life style modification (L) for 1 year. At the end, 20 of TL group and 10 of L group were analyzed. Those who showed NAS improvement ≥ 2 or NAS improvement ≥ 1 with fibrosis improvement ≥ 1 were considered as responders.

RESULTS

Baseline alanine aminotransferase (ALT), aspartate aminotransferase (AST), insulin resistance index, components of metabolic syndrome, age, and sex were similar in both groups. At the end of study, NAS improvement in TL and L groups was 2.15 ± 1.66 and 1.10 ± 0.57 (P = 0.017) and fibrosis improvement was 0.65 ± 0.93 and -0.30 ± 0.48 (P = 0.001), respectively. NAS improved by ≥ 2 in 13 (65%) and 2 (20%) patients and fibrosis score improved by ≥ 1 in 8 (40%) patients and none of the patients in TL group and L group, respectively. Telmisartan and life style modification could improve steatosis, ballooning, lobular inflammation, and fibrosis. Life style modification could improve ballooning only, but fibrosis deteriorated. TL group showed improvement in NAS and fibrosis score [P value: 0.035; odds ratio (OR) =92.07, confidence interval (CI) =1.39-6106] to the level of response by regression analysis. Weight reduction and improvement of metabolic syndrome did not influence the response. There were similar minor adverse events in both groups.

CONCLUSION

Telmisartan improved NAS and fibrosis score in NASH with insignificant adverse events.

Treatment of nonalcoholic fatty liver disease: Where do we stand? an overview

Nonalcoholic fatty liver disease (NAFLD) is currently the most common liver disease worldwide, the prevalence of which had progressively increased over the past 10 years where other liver diseases remained at the same prevalence rates or are expected to decrease as in the case of hepatitis C virus (HCV). The treatment of NAFLD is of prime concern to health care professionals and patients due to the significant mortality and morbidity it implies; the problem is further escalated by the fact that standard of care medications targeting NAFLD remain experimental and without evidence base. Treatment nowadays is focused on lifestyle modification and managing the comorbid associated diseases, with a possible role for some hepatic protective agents. This review presents all the medications that had been proposed and used for the treatment of NAFLD with or without scientific rationale and includes agents for weight loss, insulin sensitizers, drugs that reduce blood lipids, glucagon-mimetics, drugs that may reduce fibrosis, angiotensin receptor blockers, and medicines believed to reduce endoplasmic reticular stress such as vitamin E, ursodeoxycholic acid, and S-adenosyl methionine. A quick review of the newer agents that proved to be promising such as obeticholic acid and GFT505 and the medicines that are still in the pipeline is also presented.

Practice patterns in NAFLD and NASH: real life differs from published guidelines

BACKGROUND

Management guidelines from the American Association for the Study of Liver Diseases/American College of Gastroenterology/American Gastroenterology Association published in 2012 for nonalcoholic fatty liver disease (NAFLD) and steatohepatitis (NASH) recommend weight loss, vitamin E and pioglitazone as effective therapies for the treatment of biopsy-confirmed NASH. However, little is known about how physicians in the US diagnose NASH or whether published guidelines are being followed.

METHODS

We assessed current diagnostic and treatment patterns of the management of NAFLD and NASH among academic gastroenterologists and hepatologists in the US using a standardized survey developed to collect information regarding respondents' practice environments, diagnostic techniques, and medication usage in patients with NAFLD/NASH.

RESULTS

We invited 482 gastroenterologists and hepatologists, predominantly from academic centers, of whom 163 completed the survey. Only 24% of providers routinely perform liver biopsy, predominantly among patients with elevated serum aminotransferases. Vitamin E is prescribed regularly by 70% while only 14% routinely prescribe pioglitazone. Despite recommendations to the contrary, ~25% prescribe pioglitazone or vitamin E without biopsy confirmation of NASH. Metformin is used as frequently as pioglitazone despite its proven lack of efficacy in NASH. Overall, 40-73% adhere to published guidelines, depending on the specific question. There was no significant difference seen in adherence to guidelines between gastroenterologists and hepatologists.

CONCLUSION

This survey suggests that clinical practice patterns among gastroenterologists and hepatologists for the management of NASH frequently diverge from published practice guidelines. Although liver biopsy remains the gold standard to diagnose NASH, less than 25% of respondents routinely require it to make the diagnosis of NASH. We conclude that NASH is underdiagnosed in gastroenterology and hepatology practices, highlighting the need to refine noninvasive diagnostic tools.

Effect of Roux-en-Y gastric bypass on nonalcoholic fatty liver disease evaluated through NAFLD fibrosis score: a prospective study

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is common among subjects who undergo bariatric surgery and its postsurgical improvement has been reported. This study aimed to determine the evolution of liver disease evaluated through NAFLD fibrosis score 12 months after surgery.

METHODS

It is a prospective cohort study which evaluated patients immediately before and 12 months following Roux-en-Y gastric bypass (RYGB).

RESULTS

Mean score decreased from 1.142 to 0.066; surgery led to a resolution rate of advanced fibrosis of 55 %. Resolution was statistically associated with female gender, percentage of excess weight loss, postsurgical body mass index, postsurgical platelet count, and diabetes resolution.

CONCLUSIONS

As previously reported by studies in which postsurgical biopsies were performed, RYGB leads to a great resolution rate of liver fibrosis. Since postsurgical biopsy is not widely available and has a significant risk, calculation of NAFLD fibrosis score is a simple tool to evaluate this evolution through a noninvasive approach.

Epidemiological modifiers of non-alcoholic fatty liver disease: Focus on high-risk groups

An improved understanding of non-alcoholic fatty liver disease epidemiology would lead to identification of individuals at high risk of developing chronic liver disease and extra-hepatic complications, thus contributing to more effective case finding of non-alcoholic fatty liver disease among selected groups. We aimed to illustrate the epidemiology of non-alcoholic fatty liver disease in high-risk groups, which were identified based on existing literature. To this end, PubMed was searched to retrieve original articles published until May 2015 using relevant and pertinent keywords "nonalcoholic fatty liver disease" and "diabetes", "obesity", "hyperlipidaemia", "familial heterozygous hypobetalipoproteinaemia", "hypertension", "metabolic syndrome", "ethnicity", "family history" or "genetic polymorphisms". We found that age, sex and ethnicity are major physiological modifiers of the risk of non-alcoholic fatty liver disease, along with belonging to "non-alcoholic fatty liver disease families" and carrying risk alleles for selected genetic polymorphisms. Metabolic syndrome, diabetes, obesity, mixed hyperlipidaemia and hypocholesterolaemia due to familial hypobetalipoproteinaemia are the major metabolic modifiers of non-alcoholic fatty liver disease risk. Compared with these metabolic conditions, however, arterial hypertension appears to carry a relatively more modest risk of non-alcoholic fatty liver disease. A better understanding of the epidemiology of non-alcoholic fatty liver disease may result in a more liberal policy of case finding among high-risk groups.