Bariatric surgery for non-alcoholic steatohepatitis in obese patients

A new noninvasive technique for estimating hepatic triglyceride: will liver biopsy become redundant in diagnosing non-alcoholic fatty liver disease?

Obesity and metabolic syndrome are healthcare problems that continue to rise in frequency worldwide. Both phenotypes are a strong predictor for development of liver steatosis in the context of non-alcoholic fatty liver disease or non-alcoholic steatohepatitis. Ultrasound may detect steatosis, but its sensitivity is limited and liver biopsy is still considered to be the gold standard. Less invasive techniques that accurately quantify liver steatosis are warranted. Jiménez-Agüero and colleagues propose that multi-echo magnetic resonance imaging might be such a diagnostic tool. They validated multi-echo magnetic resonance imaging with measured hepatic triglyceride concentration. Their results show that this innovative technique measures the grade of steatosis in different clinical situations. Therefore, multi-echo magnetic resonance imaging might be considered for monitoring liver steatosis as an intermediate endpoint. Wide clinical applicability is limited though, as it does not allow differentiation between non-alcoholic fatty liver disease and non-alcoholic steatohepatitis.

Treatment of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is now the commonest cause of chronic liver disease in developed countries. Treatment depends on the stage of disease, and non-invasive methods for risk stratification are urgently needed. Lifestyle modification (aimed at weight loss and increasing physical activity) and management of the features of metabolic syndrome are vital for all patients with NAFLD. Metformin is the first-line therapy for diabetic patients with NAFLD and also reduces the risk of hepatocellular carcinoma. Clinicians should have a low threshold for introducing a statin for the management of dyslipidaemia. Antihypertensive agents that target the renin-angiotensin system should be first-line in NAFLD for the management of hypertension. For patients with progressive disease, liver-directed pharmacotherapy with vitamin E should be considered. Non-alcoholic steatohepatitis cirrhosis is an increasingly common indication for liver transplantation.

Modern approach to the clinical management of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the most common and emerging form of chronic liver disease worldwide. It includes a wide spectrum of liver diseases ranging from simple fatty liver to steatohepatitis, which may progress to cirrhosis, liver cancer, and liver mortality. Common metabolic diseases, which are well established cardiovascular risk factors, have been associated to NAFLD and cardiovascular disease is the single most important cause of morbidity and mortality in this patient population. The pathogenesis of NAFLD appears multifactorial and many mechanisms have been proposed as possible causes of fatty liver infiltration. Management of fatty liver has become a major challenge to healthcare systems as the consequence of the increasing rates of obesity worldwide. First-line management focuses on lifestyle modifications. Moderate weight reduction either by dietary restriction or by increased habitual physical activity is safe and highly recommended. Several therapeutic interventions have been proposed. These include insulin sensitizer agents, lipid lowering drugs, antioxidants such as vitamin E and supplementation of vitamin D₃. However, therapeutic strategies have been largely empirical so far, and experimental trials have mostly been carried out in uncontrolled settings with small sample sizes. Metabolic conditions such as diabetes mellitus, obesity, hypertension and hyperlipidemia, should be strongly considered and a multidisciplinary approach should be personalized for individual patients. Treatment of co-morbidities should be regarded as of paramount importance in the management of these patients. The purpose of this review is to examine different approaches for the clinical management of non-alcoholic fatty liver disease.

Herbal medicines for the treatment of nonalcoholic steatohepatitis: current scenario and future prospects

Nonalcoholic steatohepatitis (NASH) is a multifactorial disease and has close correlations with other metabolic disorders. This makes its treatment difficult using a single pharmacological drug. Use of plant extract/decoction or polyherbal formulation to treat various liver diseases is very well mentioned in various traditional systems of medicine (Ayurveda, Japanese or traditional Chinese Medicine, and Kampo medicine). Medicinal herbs are known for their multifaceted implications and thus can form an effective treatment schedule against NASH. Till date, several plant extracts, polyherbal formulations, and phytochemicals have been evaluated for their possible therapeutic potential in preventing onset and progression of NASH in experimental models, but clinical studies using the same are sparse. Herbal extracts with antioxidants, antidiabetic, and antihyperlipidemic properties have been shown to ameliorate symptoms of NASH. This review article is a meticulous compilation of our current knowledge on the role of natural products in alleviating NASH and possible lacunae in research that needs to be addressed.

A dietary restriction influences the progression but not the initiation of MSG-Induced nonalcoholic steatohepatitis

The metabolic syndrome is a major worldwide health care issue and a dominant risk factor for cardiovascular disease. The liver manifestations of this syndrome include nonalcoholic fatty liver disease (NAFLD) and its progressive variant nonalcoholic steatohepatitis (NASH). Although significant research has been performed, the basic pathogenesis of NAFLD/NASH remains controversial and effective treatments are still unavailable. We have previously reported on a murine model of NASH induced by the neonatal injection of monosodium glutamate (MSG), which includes the clinical manifestations of central obesity, diabetes, hyperlipidemia, and ultimately liver inflammation, fibrosis, and cancer. Although MSG is considered a safe food additive, its administration to pregnant rats increases the voracity and growth hormone levels in the offspring. To further understand the biology of this model, we have investigated the influence of the calorie intake on these clinical manifestations by feeding animals a restrictive diet. MSG-treated animals fed a restrictive diet continue to manifest obesity and early stage NASH but have improvements in serum lipid profiles. At 12 months of age, mice had manifestations of obesity, whether animals were fed a restricted or control diet, but animals fed a restrictive diet had a reduction in the progression of NASH. In conclusion, MSG appears to be a critical factor in the initiation of obesity, whereas calorie intake may modulate the progression of disease.

Clinical approaches to non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) ranges from simple steatosis to nonalcoholic steatohepatitis (NASH), leading to fibrosis and potentially cirrhosis, and it is one of the most common causes of liver disease worldwide. NAFLD is associated with other medical conditions such as metabolic syndrome, obesity, cardiovascular disease and diabetes. NASH can only be diagnosed through liver biopsy, but noninvasive techniques have been developed to identify patients who are most likely to have NASH or fibrosis, reducing the need for liver biopsy and risk to patients. Disease progression varies between individuals and is linked to a number of risk factors. Mechanisms involved in the pathogenesis are associated with diet and lifestyle, influx of free fatty acids to the liver from adipose tissue due to insulin resistance, hepatic oxidative stress, cytokines production, reduced very low-density lipoprotein secretion and intestinal microbiome. Weight loss through improved diet and increased physical activity has been the cornerstone therapy of NAFLD. Recent therapies such as pioglitazone and vitamin E have been shown to be beneficial. Omega 3 polyunsaturated fatty acids and statins may offer additional benefits. Bariatric surgery should be considered in morbidly obese patients. More research is needed to assess the impact of these treatments on a long-term basis. The objective of this article is to briefly review the diagnosis, management and treatment of this disease in order to aid clinicians in managing these patients.

Clinical approaches to non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) ranges from simple steatosis to nonalcoholic steatohepatitis (NASH), leading to fibrosis and potentially cirrhosis, and it is one of the most common causes of liver disease worldwide. NAFLD is associated with other medical conditions such as metabolic syndrome, obesity, cardiovascular disease and diabetes. NASH can only be diagnosed through liver biopsy, but noninvasive techniques have been developed to identify patients who are most likely to have NASH or fibrosis, reducing the need for liver biopsy and risk to patients. Disease progression varies between individuals and is linked to a number of risk factors. Mechanisms involved in the pathogenesis are associated with diet and lifestyle, influx of free fatty acids to the liver from adipose tissue due to insulin resistance, hepatic oxidative stress, cytokines production, reduced very low-density lipoprotein secretion and intestinal microbiome. Weight loss through improved diet and increased physical activity has been the cornerstone therapy of NAFLD. Recent therapies such as pioglitazone and vitamin E have been shown to be beneficial. Omega 3 polyunsaturated fatty acids and statins may offer additional benefits. Bariatric surgery should be considered in morbidly obese patients. More research is needed to assess the impact of these treatments on a long-term basis. The objective of this article is to briefly review the diagnosis, management and treatment of this disease in order to aid clinicians in managing these patients.

Obesity-associated nonalcoholic fatty liver disease

Obesity is strongly associated with the prevalence of nonalcoholic fatty liver disease (NAFLD) in adult and pediatric populations. Nutrition, physical activity, and behavioral modifications are critical components of the treatment regimen for all obese patients with NAFLD. Bariatric surgeries that affect or restrict the flow of food through the gastrointestinal tract may improve liver histology in morbidly obese patients with nonalcoholic steatohepatitis (NASH), although randomized clinical trials and quasi-randomized clinical studies are lacking. Early detection of NASH and hepatic fibrosis using noninvasive biochemical and imaging markers that may replace liver biopsy is the current challenge.

Metabolic surgery: shifting the focus from glycaemia and weight to end-organ health

Bariatric surgery is the most effective treatment for weight loss and glycaemic control. The focus of clinical studies and clinical experience has predominantly been on the numerical reductions of bodyweight and glucose after surgery. In this Series paper, we examine evidence on the efficacy of bariatric surgery for pancreatic, renal, retinal, peripheral nervous, cardiovascular, hepatic, and reproductive end-organ damage or disease. The overall conclusions are that, in most cases, patients' end-organ damage is expected to either stabilise or improve postoperatively. However, some of these clinical outcomes have not been assessed with robust methods and, in many cases, do not have support from randomised controlled clinical trials comparing bariatric surgery with non-surgical interventions. Such trials are urgently needed to inform patients and clinicians on whether the risks of surgery outweigh the significant benefits for end-organ health.

Nonalcoholic fatty liver disease and bariatric surgery in adolescents

Obesity is a multi-organ system disease with underlying insulin resistance and systemic chronic inflammation. Nonalcoholic fatty liver disease (NAFLD) is a hepatic manifestation of the underlying metabolic dysfunction. This review provides a highlight of the current understanding of NAFLD pathogenesis and disease characteristics, with updates on the challenges of NAFLD management in obese and severely obese (SO) patients and recommendations for the pediatric surgeons' role in the care of SO adolescents.

Impact of nutrition and obesity on chronic liver disease

Undernutrition and obesity are at opposite ends of a spectrum that has an enormous impact on all aspects of liver diseases. The myriad effects of the opposing ends of the nutrition spectrum have led to a wealth of research aimed at elucidating the exact mechanisms of how they cause liver damage. In this article, the role of the liver in nutrient and energy metabolism is discussed, as well as the known and possible effects of specific nutrient deficiencies and obesity.

Surgical management of obesity in patients with morbid obesity and nonalcoholic fatty liver disease

Most patients with severe complex obesity presenting for bariatric-metabolic surgery have nonalcoholic fatty liver disease (NAFLD). NAFLD is associated with central obesity, insulin resistance, type 2 diabetes, hypertension, and obesity-related dyslipidemia. Weight loss should be a primary therapy for NAFLD. However, evidence supporting intentional weight loss as a therapy for NAFLD is limited. Bariatric-metabolic surgery provides the most reliable method of achieving substantial sustained weight loss and the most commonly used procedures are associated with reduced steatosis and lobular inflammatory changes, but there are mixed reports regarding fibrosis. Surgery should complement treatment of obesity-related comorbidity, but not replace established therapy.

Bariatric surgery and non-alcoholic Fatty liver disease: current and potential future treatments

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are increasingly common cause of chronic liver disease worldwide. The diagnosis of NASH is challenging as most affected patients are symptom-free and the role of routine screening is not clearly established. Most patients with severe obesity who undergo bariatric surgery have NAFLD, which is associated insulin resistance, type 2 diabetes mellitus (T2DM), hypertension, and obesity-related dyslipidemia. The effective treatment for NAFLD is weight reduction through lifestyle modifications, antiobesity medication, or bariatric surgery. Among these treatments, bariatric surgery is the most reliable method for achieving substantial, sustained weight loss. This procedure is safe when performed by a skilled surgeon, and the benefits include reduced weight, improved quality of life, decreased obesity-related comorbidities, and increased life expectancy. Further research is urgently needed to determine the best use of bariatric surgery with NAFLD patients at high risk of developing liver cirrhosis and its role in modulating complications of NAFLD, such as T2DM and cardiovascular disease. The current evidence suggests that bariatric surgery for patients with severe obesity decreases the grade of steatosis, hepatic inflammation, and fibrosis. However, further long-term studies are required to confirm the true effects before recommending bariatric surgery as a potential treatment for NASH.

Review of treatment options for nonalcoholic fatty liver disease

Although the future of NAFLD and NASH treatment has many promising agents, clinicians are currently faced with limited options with an emphasis on lifestyle modification. Figs. 1 and 2 summarize current practices for the diagnosis and treatment of NAFLD with the understanding that each patient's treatment must be customized to their comorbidities, exercise tolerance, and willingness to comply with therapy.

Gastrointestinal complications of diabetes

This review provides an overview of the vast gastrointestinal tract complications of diabetes that can occur from the mouth to the anus. The presentation, diagnosis, and management of gastrointestinal disorders, ranging from gastroparesis, celiac disease, and bacterial overgrowth to nonalcoholic fatty liver disease, are reviewed to heighten awareness. When managing care of patients with diabetes, one should keep in mind the potential gastrointestinal complications, as well as the frequent disorders that are not related to diabetes.

[Diagnosis of and therapy for hepatocellular carcinoma]

The interdisciplinary guidelines at the S3 level on the diagnosis of and therapy for hepatocellular carcinoma (HCC) constitute an evidence- and consensus-based instrument that is aimed at improving the diagnosis of and therapy for HCC since these are very challenging tasks. The purpose of the guidelines is to offer the patient (with suspected or confirmed HCC) adequate, scientifically based and up-to-date procedures in diagnosis, therapy and rehabilitation. This holds not only for locally limited or focally advanced disease but also for the existence of recurrences or distant metastases. Besides making a contribution to an appropriate health-care service, the guidelines should also provide the foundation for an individually adapted, high-quality therapy. The explanatory background texts should also enable non-specialist but responsible colleagues to give sound advice to their patients concerning specialist procedures, side effects and results. In the medium and long-term this should reduce the morbidity and mortality of patients with HCC and improve their quality of life.

Nonalcoholic fatty liver disease: current issues and novel treatment approaches

Nonalcoholic fatty liver disease (NAFLD) is considered the most common liver disorder in the Western world. It is commonly associated with insulin resistance, obesity, dyslipidaemia, type 2 diabetes mellitus (T2DM) and cardiovascular disease. Nonalcoholic steatohepatitis (NASH) is characterized by steatosis with necroinflammation and eventual fibrosis, which can lead to end-stage liver disease and hepatocellular carcinoma. Its pathogenesis is complex, and involves a state of 'lipotoxicity' in which insulin resistance, with increased free fatty acid release from adipose tissue to the liver, play a key role in the onset of a 'lipotoxic liver disease' and its progression to NASH. The diagnosis of NASH is challenging, as most affected patients are symptom free and the role of routine screening is not clearly established. A complete medical history is important to rule out other causes of fatty liver disease (alcohol abuse, medications, other). Plasma aminotransferase levels and liver ultrasound are helpful in the diagnosis of NAFLD/NASH, but a liver biopsy is often required for a definitive diagnosis. However, there is an active search for plasma biomarkers and imaging techniques that may non-invasively aid in the diagnosis. The treatment of NASH requires a multifaceted approach. The goal is to reverse obesity-associated lipotoxicity and insulin resistance via lifestyle intervention. Although there is no pharmacological agent approved for the treatment of NAFLD, vitamin E (in patients without T2DM) and the thiazolidinedione pioglitazone (in patients with and without T2DM) have shown the most consistent results in randomized controlled trials. This review concentrates on our current understanding of the disease, with a focus on the existing therapeutic approaches and potential future pharmacological developments for NAFLD and NASH.

Gastrointestinal complications of diabetes mellitus

Diabetes mellitus affects virtually every organ system in the body and the degree of organ involvement depends on the duration and severity of the disease, and other co-morbidities. Gastrointestinal (GI) involvement can present with esophageal dysmotility, gastro-esophageal reflux disease (GERD), gastroparesis, enteropathy, non alcoholic fatty liver disease (NAFLD) and glycogenic hepatopathy. Severity of GERD is inversely related to glycemic control and management is with prokinetics and proton pump inhibitors. Diabetic gastroparesis manifests as early satiety, bloating, vomiting, abdominal pain and erratic glycemic control. Gastric emptying scintigraphy is considered the gold standard test for diagnosis. Management includes dietary modifications, maintaining euglycemia, prokinetics, endoscopic and surgical treatments. Diabetic enteropathy is also common and management involves glycemic control and symptomatic measures. NAFLD is considered a hepatic manifestation of metabolic syndrome and treatment is mainly lifestyle measures, with diabetes and dyslipidemia management when coexistent. Glycogenic hepatopathy is a manifestation of poorly controlled type 1 diabetes and is managed by prompt insulin treatment. Though GI complications of diabetes are relatively common, awareness about its manifestations and treatment options are low among physicians. Optimal management of GI complications is important for appropriate metabolic control of diabetes and improvement in quality of life of the patient. This review is an update on the GI complications of diabetes, their pathophysiology, diagnostic evaluation and management.

Evolving therapies for liver fibrosis

Fibrosis is an intrinsic response to chronic injury, maintaining organ integrity when extensive necrosis or apoptosis occurs. With protracted damage, fibrosis can progress toward excessive scarring and organ failure, as in liver cirrhosis. To date, antifibrotic treatment of fibrosis represents an unconquered area for drug development, with enormous potential but also high risks. Preclinical research has yielded numerous targets for antifibrotic agents, some of which have entered early-phase clinical studies, but progress has been hampered due to the relative lack of sensitive and specific biomarkers to measure fibrosis progression or reversal. Here we focus on antifibrotic approaches for liver that address specific cell types and functional units that orchestrate fibrotic wound healing responses and have a sound preclinical database or antifibrotic activity in early clinical trials. We also touch upon relevant clinical study endpoints, optimal study design, and developments in fibrosis imaging and biomarkers.

Cirrhosis Regression and Subclassification

The end point of liver fibrosis in almost all chronic liver diseases is cirrhosis. Progression to cirrhosis is accompanied by vascular remodeling and regeneration with important functional and hemodynamic consequences that include development of portal hypertension and eventually decompensation and death. Fibrosis can regress following successful treatment of the underlying disease. However, most common fibrosis scoring systems are not equipped for assessing this aspect. Nodule size, septal width and fibrosis area seem to correlate with disease severity and progression in cirrhosis. Classification systems based on nodule size, septal width, and fibrosis area need to be further validated.

Bariatric surgery as a treatment option in patients with type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is a leading cause of blindness, non-traumatic amputation and end-stage renal disease as well as a major cardiovascular risk factor. Tight glycemic control reduces the incidence of microvascular complications of T2DM whereas its effects on macrovascular complication are more controversial. However, glycemic targets are achieved by a minority of diabetic patients despite the availability of several antidiabetic agents. In the present commentary, we discuss the findings of two recent randomized studies that compared bariatric surgery with medical treatment in patients with uncontrolled T2DM. Both studies showed that bariatric surgery results in remission of T2DM in the majority of patients. However, both studies were limited to relatively young patients without comorbidities, had relatively short follow-up and did not assess the effects of surgery on T2DM complications. Moreover, the perioperative complications of bariatric surgery and its limited availability in some areas are additional barriers to the wider implementation of this therapeutic approach. On the other hand, the elucidation of the mechanisms underpinning the resolution of T2DM following bariatric surgery might result in the development of novel, more effective pharmacotherapies for this common disease.

Long-term effect of bariatric surgery on liver enzymes in the Swedish Obese Subjects (SOS) study

Background and Aim

Obesity is associated with elevated serum transaminase levels and non-alcoholic fatty liver disease and weight loss is a recommended therapeutic strategy. Bariatric surgery is effective in obtaining and maintaining weight loss. Aim of the present study was to examine the long-term effects of bariatric surgery on transaminase levels in obese individuals.

Methods

The Swedish Obese Subjects (SOS) study is a prospective controlled intervention study designed to compare the long-term effects of bariatric surgery and usual care in obese subjects. A total of 3,570 obese participants with no excess of alcohol consumption at baseline (1,795 and 1,775 in the control and surgery group, respectively) were included in the analyses. Changes in transaminase levels during follow-up were compared in the surgery and control groups.

Results

Compared to usual care, bariatric surgery was associated with lower serum ALT and AST levels at 2- and 10- year follow up. The reduction in ALT levels was proportional to the degree of weight loss. Both the incidence of and the remission from high transaminase levels were more favorable in the surgery group compared to the control group. Similarly, the prevalence of ALT/AST ratio <1 was lower in the surgery compared to the control group at both 2- and 10-year follow up.

Conclusions

Bariatric surgery results in a sustained reduction in transaminase levels and a long-term benefit in obese individuals.

Fatty liver disease in children--what should one do?

The world's population is increasingly overweight and obese. According to the World Health Organization (WHO) as of 2010, 43 million children under the age of five were overweight. Once considered to be limited to developed countries, overweight and obese children are now found in low- and middle-income countries, though most commonly in urban areas. Furthermore the WHO now cites the conditions of overweight and obesity as being associated with more deaths around the globe than those associated with being underweight. With this increased prevalence of overweight and obese children has come a host of other medical problems including nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). This review will focus on NAFLD and NASH, their definitions, epidemiology, diagnosis and treatment. The authors will also discuss NAFLD in the Indian subcontinent, and the future of NAFLD and NASH.

Benign, premalignant, and malignant lesions encountered in bariatric surgery

BACKGROUND

Obesity is associated with several comorbidities like diabetes, hypertension, hyperlipidemia, and obstructive sleep apnea. It is also well established that obese patients have an increased risk of several types of cancer like kidney, pancreas, endometrial, breast, and others. The bariatric surgeon needs to be aware of the problem of benign tumors and cancer in obese patients as well as the optimal management of these conditions that may be present at the time of evaluation for bariatric surgery, during the surgical procedure, and in the postoperative period.

DATABASE

A PubMed search for the words "cancer" and "bariatric surgery" and subsequent review of the abstracts identified 40 articles concerning cancerous, benign, and premalignant conditions in bariatric surgery patients. Data were then extracted from full-text articles.

CONCLUSION

Bariatric surgery decreases cancer risk especially in women. RYGB can be an effective treatment for Barrett's esophagus. Patients having esophageal cancer should not undergo bariatric surgery, while those who develop the same postoperatively are usually managed by a combined abdominal and thoracic approach (Ivor Lewis technique). Gastric cancer of the remnant stomach is usually managed by a remnant gastrectomy. A remnant gastrectomy during RYGB would be necessary in conditions that require endoscopic surveillance of the stomach like gastric polyps, intestinal metaplasia, and carcinoid tumors. Sleeve gastrectomy is an excellent option in a patient with GIST or a carcinoid who needs a bariatric operation. Preoperative endoscopy usually does not detect malignant conditions. Postoperative evaluation of the bypassed stomach is possible using various percutaneous and novel endoscopic techniques.

Nonalcoholic fatty liver disease: an emerging threat to obese and diabetic individuals

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease in the Western world and its incidence is increasing rapidly. NAFLD is a spectrum ranging from simple steatosis, which is relatively benign hepatically, to nonalcoholic steatohepatitis (NASH), which can progress to cirrhosis. Obesity, insulin resistance, type 2 diabetes mellitus, and dyslipidemia are the most important risk factors for NAFLD. Due to heavy enrichment with metabolic risk factors, individuals with NAFLD are at significantly higher risk for cardiovascular disease. Individuals with NAFLD have higher incidence of type 2 diabetes. The diagnosis of NAFLD requires imaging evidence of hepatic steatosis in the absence of competing etiologies including significant alcohol consumption. Liver biopsy remains the gold standard for diagnosing NASH and for determining prognosis. Weight loss remains a cornerstone of treatment. Weight loss of ∼5% is believed to improve steatosis, whereas ∼10% weight loss is necessary to improve steatohepatitis. A number of pharmacologic therapies have been investigated to treat NASH, and agents such as vitamin E and thiazolidinediones have shown promise in select patient subgroups.

Bariatric surgery: the challenges with candidate selection, individualizing treatment and clinical outcomes

Obesity is recognized as a global health crisis. Bariatric surgery offers a treatment that can reduce weight, induce remission of obesity-related diseases, and improve the quality of life. In this article, we outline the different options in bariatric surgery and summarize the recommendations for selecting and assessing potential candidates before proceeding to surgery. We present current data on post-surgical outcomes and evaluate the psychosocial and economic effects of bariatric surgery. Finally, we evaluate the complication rates and present recommendations for post-operative care.

Have guidelines addressing physical activity been established in nonalcoholic fatty liver disease?

The purpose of this review was to highlight, in relation to the currently accepted pathophysiology of non-alcoholic fatty liver disease (NAFLD), the known exercise habits of patients with NAFLD and to detail the benefits of lifestyle modification with exercise (and/or physical activity) on parameters of metabolic syndrome. More rigorous, controlled studies of longer duration and defined histopathological end-points comparing exercise alone and other treatment are needed before better, evidence-based physical activity modification guidelines can be established, since several questions remain unanswered.

Bariatric surgery: a best practice article

Bariatric surgery can effectively reduce body weight and treat obesity associated metabolic diseases such as diabetes mellitus. There are also benefits for an individual's functional status and psychological health. A multi-disciplinary evaluation should be offered to the individual as the first essential step in considering bariatric surgery as a treatment. This evaluation should include a thorough medical assessment, as well as psychological and dietetic assessments. In this best practice article, we outline the current recommendations for referral for bariatric surgery. We also present the data for pre-operative assessment before bariatric surgery, with particular reference to cardiovascular disease and obstructive sleep apnoea. We describe the literature on outcomes after bariatric surgery, including the results for mortality, weight loss, remission of diabetes and associated endocrine disorders such as hypogonadism. Within this review, we will illustrate the impact of bariatric surgery on self-image, psychological health and perceived health and functional status. Finally, we briefly detail the potential complications of bariatric surgery, and offer advice on post-operative care and surveillance.

Effect of bariatric surgery on liver fibrosis

BACKGROUND

Although bariatric surgery has been shown to improve hepatic steatosis in morbidly obese patients, the effect of weight loss on hepatic fibrosis has not been determined. Since the prognosis of patients with nonalcoholic fatty liver disease is closely related to the development of hepatic fibrosis, it is important to determine the hepatic histology of these patients after weight loss. We therefore evaluated the prevalence of hepatic fibrosis in morbidly obese patients undergoing bariatric surgery and assessed the correlation of histologic changes with weight loss.

METHODS

We retrospectively evaluated 78 morbidly obese patients who underwent gastric bypass. Liver biopsies were taken during surgery and after weight loss, and the correlations between histologic findings and hepatic fibrosis were determined.

RESULTS

Of the 78 patients, 35 (44.8%) had fibrosis at first biopsy, and 24 (30.8%) had hepatic fibrosis after weight loss, including 19 of the 35 patients (54.3%) with fibrosis at first biopsy and 5 of the 43 (11.6%) without hepatic fibrosis at first biopsy (P = 0.027).

CONCLUSIONS

Weight loss in morbidly obese patients was associated with a reduction in the prevalence of hepatic fibrosis.

Improvement of nonalcoholic fatty liver disease after bariatric surgery in morbidly obese Chinese patients

BACKGROUND

Obesity is a risk factor for nonalcoholic fatty liver disease (NAFLD), which appears to improve after weight loss induced by bariatric surgery in Western countries. The present study aims to determine the alterations of clinical measurements and liver histology of NAFLD after bariatric surgery in morbidly obese Chinese patients.

METHODS

Between November 2006 and December 2007, 21 morbidly obese patients receiving intra-operative liver biopsy and follow-up liver biopsy 1 year after laparoscopic Roux-en-Y gastric bypass were enrolled. NAFLD activity score (NAS) and fibrosis stage were histologically evaluated.

RESULTS

The mean body mass index fell from 43.8 ± 7.5 to 28.3 ± 4.6 kg/m(2) (P < 0.01). Biochemical improvement was found in serum levels of alanine aminotransferase (P < 0.01) and γ-glutamyltransferase (P < 0.01), but not aspartate aminotransferase (P = 0.66). Histological improvement was noted in NAS (P < 0.01) and individual components, including steatosis (P < 0.01), ballooning degeneration (P < 0.01), and lobular inflammation (P = 0.02). Pre-operatively, 4 (19.0%), 11 (52.4%), and 6 (28.6%) patients were found to have NAS >/=5, 3 or 4, and </=2, respectively. All patients had NAS </=2 after surgery. Fibrosis stage also showed significant improvement (P < 0.01).

CONCLUSIONS

Bariatric surgery can achieve a dramatic improvement of NAFLD both biochemically and histologically in morbidly obese Chinese patients.

Brief report: approaches to 31P-MRS in awake, non-sedated children with and without autism spectrum disorder

We piloted a suite of approaches aimed to facilitate a successful series of up to four brain and muscle (31)Phosphorus-Magnetic Resonance Spectroscopy ((31)P-MRS) scans performed in one session in 12 awake, non-sedated subjects (ages 6-18), 6 with autism spectrum disorders (ASD) and 6 controls. We targeted advanced preparation, parental input, physical comfort, short scan protocols, allocation of extra time, and subject emotional support. 100% of subjects completed at least one brain scan and one leg muscle scan: 42 of 46 attempted scans were completed (91%), with failures dominated by exercise muscle scans (completed in 6/6 controls but 3/6 cases). One completed scan lacked usable data unrelated to subject/scan procedure (orthodonture affected a frontal brain scan). As a group, these methods provide a foundation for conduct and enhancement of future MR studies in pediatric subjects with ASD.

Management of Non-alcoholic Fatty Liver Disease and Steatohepatitis

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of abnormal liver enzymes and chronic liver disease in the US with expected rise in incidence paralleling the epidemic of obesity. A subset of patients with NAFLD have the progressive form of NAFLD that is termed non-alcoholic steatohepatitis (NASH), which is characterized by specific features on liver histology including hepatocellular ballooning degeneration, lobular inflammation, and zone-3 steatosis with or without peri-sinusoidal fibrosis. Non-alcoholic steatohepatitis can progress to cirrhosis and result in liver-related death. Insulin resistance is commonly seen in patients with NASH and often co-exists with other features of the metabolic syndrome including hypertension, hyperlipidemia, and obesity. Although weight loss through lifestyle modifications including dietary changes and increased physical exercise remains the backbone of management of NASH, it has proved challenging for patients to achieve and maintain weight loss goals. Thus, it is often necessary to couple lifestyle changes with another pharmacologic treatment for NASH. Insulin sensitizers including the biguanides (metformin), thiazolidinediones (pioglitazone and rosiglitazone), and glucagon-like peptide-1 receptor agonists (exenatide) are large groups of medications that have been studied for the treatment of NASH. Other agents with anti-inflammatory, anti-apoptotic, or anti-fibrotic properties which have been studied in NASH include vitamin E, pentoxifylline, betaine, and ursodeoxycholic acid. This review will provide a detailed summary on the clinical data behind the full spectrum of treatments that exist for NASH and suggest management recommendations.

Current treatment options for nonalcoholic fatty liver disease and nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease is the leading cause of liver disease in western society. It is a cause of end-stage liver disease, with increased mortality secondary to cirrhosis and its complications. It is also recognized that cardiovascular disease is a significant cause of death in these patients. Significant work evaluating various treatments has been performed in recent years; however, to date, no ideal therapy exists. Lifestyle modification remains the cornerstone of management. The present article reviews the current status of various treatment modalities evaluated in nonalcoholic fatty liver disease.

Clinical evidence for the regression of liver fibrosis

Fibrosis is a common pathological process for the majority of liver diseases which in a significant minority of patients leads to end-stage cirrhosis and/or hepatocellular carcinoma. Data emerging from small rodent models of chronic liver disease have demonstrated that fibrotic extracellular matrix can be remodelled and near-normal hepatic architecture regenerated upon cessation of injury. Moreover, regression of liver fibrosis in these model systems can be stimulated with drugs that target the activities of fibrogenic hepatic stellate cells. These findings are exciting as they suggest that established fibrosis is susceptible to regression and possibly even reversion. Alongside these experimental studies is a growing body of clinical data that suggest regression of fibrosis may also occur in liver disease patients for whom an effective treatment is available for their underlying liver injury. This paper provides an up-to-date review of the currently available clinical data and also considers technical caveats that highlight the need for caution in establishing a new dogma that human liver fibrosis is reversible.

Role of obesity and lipotoxicity in the development of nonalcoholic steatohepatitis: pathophysiology and clinical implications

As obesity reaches epidemic proportions, nonalcoholic fatty liver disease (NAFLD) is becoming a frequent cause of patient referral to gastroenterologists. There is a close link between dysfunctional adipose tissue in NAFLD and common conditions such as metabolic syndrome, type 2 diabetes mellitus, and cardiovascular disease. This review focuses on the pathophysiology of interactions between adipose tissue and target organs in obesity and the resulting clinical implications for the management of nonalcoholic steatohepatitis. The release of fatty acids from dysfunctional and insulin-resistant adipocytes results in lipotoxicity, caused by the accumulation of triglyceride-derived toxic metabolites in ectopic tissues (liver, muscle, pancreatic beta cells) and subsequent activation of inflammatory pathways, cellular dysfunction, and lipoapoptosis. The cross talk between dysfunctional adipocytes and the liver involves multiple cell populations, including macrophages and other immune cells, that in concert promote the development of lipotoxic liver disease, a term that more accurately describes the pathophysiology of nonalcoholic steatohepatitis. At the clinical level, adipose tissue insulin resistance contributes to type 2 diabetes mellitus and cardiovascular disease. Treatments that rescue the liver from lipotoxicity by restoring adipose tissue insulin sensitivity (eg, significant weight loss, exercise, thiazolidinediones) or preventing activation of inflammatory pathways and oxidative stress (ie, vitamin E, thiazolidinediones) hold promise in the treatment of NAFLD, although their long-term safety and efficacy remain to be established. Better understanding of pathways that link dysregulated adipose tissue, metabolic dysfunction, and liver lipotoxicity will result in improvements in the clinical management of these challenging patients.

Pathophysiology guided treatment of nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease is a spectrum that ranges from benign steatosis to steatohepatitis. It has become the most common cause of chronic liver disease, and yet there continues to be a lack of effective therapeutic options. This article reviews current concepts underlying the pathophysiological basis of nonalcoholic steatohepatitis from development of insulin resistance to the establishment of fibrosis. Then using a physiology-based approach, specific targeted therapeutics are reviewed along with their drawbacks. The evidence behind current therapies is based predominantly on small trials and, thus, no recommendations can be made until larger randomized trials are conducted.

Caffeine is protective in patients with non-alcoholic fatty liver disease

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD), the hepatic manifestation of metabolic syndrome, is the most common cause of primary liver disease. Although recent studies have found that coffee drinking is protective against end stage chronic liver disease, there are scarce caffeine intake data in NAFLD specifically.

AIM

To investigate the effects of dietary behaviour in NAFLD patients, using four continuous cycles of the National Health and Nutrition Examination Surveys (NHANES 2001-2008).

METHODS

Using data from four continuous cycles of NHANES, dietary intake questionnaires that list 62 nutrition components. Logistic regression was used to identify independent predictors of NAFLD among nutrition components after adjustment for potential clinical confounders. All analyses were run using sas 9.1 and SUDAAN 10.0 (SAS Institute Inc., Cary, NC, USA).

RESULTS

Of the 62 nutrient components used for the univariate analysis, 38% were significant (P-value <0.05) in NAFLD with caffeine consumption being higher in the control group (P-value <0.001). The multivariate analysis using demographics, clinical parameters and nutritional components found five factors independently associated with NAFLD [African American Race P-value <0.001); Male gender P-value <0.001); Obesity (BMI ≥ 30) P-value <0.001); Caffeine intake (mg) P-value <0.001) and total plain water consumption (g) P-value ≤ 0.02)].

CONCLUSIONS

Our analysis shows that caffeine intake is independently associated with a lower risk for NAFLD suggesting a potential protective effect. These data necessitate further research to elucidate the mechanism by which caffeine can protect against NAFLD.

Non-alcoholic steatohepatitis: the therapeutic challenge of a global epidemic

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide. Nonalcoholic steatohepatitis (NASH) reflects severe liver disease within the NAFLD spectrum and can progress to end-stage liver disease. Within this manuscript we review the available evidence for the treatment of NASH as well as the newer therapeutic agents that are currently being investigated.

An Endocrine Perspective of Nonalcoholic Fatty Liver Disease (NAFLD)

Endocrinologists are encountering patients with obesity-related complications such as metabolic syndrome (MetS) and type 2 diabetes mellitus (T2DM) on a daily basis. Nonalcoholic fatty liver disease (NAFLD) is a liver condition characterized by insulin resistance, hepatic steatosis and frequently T2DM. This is now the most common chronic liver condition in adults and is present in the majority of obese subjects. Liver fat accumulation may range from simple steatosis to severe steatohepatitis with hepatocyte necroinflammation (or nonalcoholic steatohepatitis [NASH]). Although the natural history is incompletely understood, NAFLD may lead to serious medical consequences ranging from cirrhosis and hepatocellular carcinoma to earlier onset of T2DM and cardiovascular disease (CVD). The diagnosis of NAFLD may be challenging because signs and symptoms are frequently absent or nonspecific, and thus easily missed. Liver aminotransferases may be helpful if elevated, but most times are normal in the presence of the disease. Liver imaging may assist in the diagnosis (ultrasound or MRI and spectroscopy) but a definitive diagnosis of NASH still requires a liver biopsy. This may change in the near future as novel biomarkers become available. Treatment of NAFLD includes aggressive management of associated cardiovascular risk factors and many times control of T2DM. Pioglitazone and vitamin E appear promising for patients with NASH, although long-term studies are unavailable. In summary, this review hopes to address the common clinical dilemmas that endocrinologists face in the diagnosis and management of NAFLD and increase awareness of a potentially serious medical condition.

Nonalcoholic fatty liver disease: pharmacologic and surgical options

The last decade has seen many studies examining the prevalence and natural history of NAFLD in the United States and it is clear that this disease is likely to be an important cause of liver-related morbidity in the future. Several pharmacologic therapies have shown some promise; currently, vitamin E and insulin-sensitizing agents such as pioglitazone can be considered in appropriate cases. Conservative measures to promote weight loss still have a role to play, but the obesity epidemic in the Western World has reached such proportions that bariatric surgery is proving to be an attractive option for patients with a BMI greater than 35 to 40 kg/m2. Well-designed prospective studies are required to ensure that all of these therapies are safe and effective in the long term. Newer agents will likely be investigated as the pathogenesis of NAFLD and fibrosis progression in NASH are further elucidated.