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

Comparison of triglyceride-glucose index and anthropometric obesity indices in predicting severe grades of hepatic steatosis in nonalcoholic fatty liver disease among non-diabetic obese individuals

Background and Aim

The triglyceride glucose index (TyG) has been proposed as a promising indicator of both insulin resistance (IR) and non-alcoholic fatty liver disease (NAFLD). However, the efficacy of the TyG index in predicting NAFLD has not been adequately studied, particularly in obese individuals.

Materials and Methods

We analyzed 190 morbidly obese individuals. The TyG index, anthropometric obesity indices, homeostatic model assessment (HOMA-IR), and biochemical parameters were compared. NAFLD was diagnosed by hepatic ultrasonography and classified into four grades (0, 1, 2, and 3). Individuals in grades 2 and 3 are considered to have severe steatosis, while those in grades 0 and 1 do not.

Results

The area under the curve (AUC) values of the TyG index, body mass index, neck circumferences, waist-to-hip ratio, and HOMA-IR did not differ significantly in predicting severe steatosis (0.640, 0.742, 0.725, 0.620, and 0.624 respectively). However, the AUC values of waist circumference and alanine aminotransferase provided better predictions than the TyG index (0.782, 0.744, and 0.640 respectively).

Conclusion

The TyG index is highly effective in predicting both the presence and severity of NAFLD. However, it did not outperform simple obesity indices in predicting NAFLD and its severity in obese patients.

Relationship between the changes in hepatokine levels and metabolic effects after laparoscopic sleeve gastrectomy in severely obese patients

PURPOSE

To clarify the relationships between the changes in hepatokines and weight loss, and between these changes and the metabolic effects, and the roles played by these changes, after laparoscopic sleeve gastrectomy (LSG).

METHODS

We recruited 25 Japanese patients with severe obesity, who underwent LSG. We measured two hepatokines: selenoprotein P (SeP) and leukocyte cell-derived chemotaxin 2 (LECT2), at the baseline, and then 6 months and 1 year after LSG. Finally, we compared the changes in the hepatokines with the parameters of type 2 diabetes (T2D) and non-alcoholic steatohepatitis (NASH).

RESULTS

Changes in LECT2 were correlated with the percentage of total weight loss (ρ = - 0.499, P = 0.024) and the decrease in total fat area (ρ = 0.559, P = 0.003). The changes in SeP were correlated with those in hemoglobin A1c (ρ = 0.526, P = 0.043) and the insulinogenic index (ρ = 0.638, P = 0.010) in T2D patients. In patients with NASH, the LECT2 levels were correlated with liver steatosis (ρ = 0.601).

CONCLUSIONS

SeP levels decrease in association with HbA1c reduction, whereas LECT2 levels are associated with reductions in fat mass and NASH scores after LSG. Hepatokines may be involved in the pathology of obesity and its complications.

The Long-Term Effect of Weight Loss on the Prevention of Progression to Cirrhosis among Patients with Obesity and MASH-Related F3 Liver Fibrosis

This multi-center retrospective study examined the effect of weight loss on the prevention of progression to cirrhosis in a sample exclusively composed of patients with obesity and MASH-related F3 liver fibrosis. Adult patients with obesity and biopsy-confirmed MASH-related F3 liver fibrosis (n = 101) from two liver transplant centers in the US were included in the study. A higher proportion of patients who did not progress to cirrhosis achieved >5% weight loss at follow-up (59% vs. 30%, p = 0.045). In multivariable analysis, patients with >5% weight loss at follow-up had a lower hazard of developing cirrhosis compared to patients with no weight loss or weight gain (HR: 0.29, 95%, CI: 0.08-0.96); whereas, diabetes (HR: 3.24, 95%, CI: 1.21-8.67) and higher LDL levels (HR: 1.02, 95%, CI: 1.01-1.04) were associated with higher hazards of progression to cirrhosis. Weight loss >5% has the potential to prevent disease progression to cirrhosis in patients with obesity and MASH-related F3 liver fibrosis. The realization of this benefit requires weight loss maintenance longer than one year. Larger prospective studies are needed to determine how weight loss impacts other patient-centered outcomes such as mortality, hepatic decompensation, and hepatocellular carcinoma in patients with obesity and MASH-related F3 liver fibrosis.

Celiac artery mesenteric fat measurement with endosonography (CAMEUS) reliably correlates with obesity and related comorbidities

Background

Visceral fat represents a metabolically active entity linked to adverse metabolic sequelae of obesity. We aimed to determine if celiac artery mesenteric fat thickness can be reliably measured during endoscopic ultrasound (EUS), and if these measurements correlate with metabolic disease burden.

Methods

This was a retrospective analysis of patients who underwent celiac artery mesenteric fat measurement with endosonography (CAMEUS) measurement at a tertiary referral center, and a validation prospective trial of patients with obesity and nonalcoholic steatohepatitis who received paired EUS exams with CAMEUS measurement before and after six months of treatment with an intragastric balloon.

Results

CAMEUS was measured in 154 patients [56.5% females, mean age 56.5 ± 18.0 years, body mass index (BMI) 29.8 ± 8.0 kg/m2] and was estimated at 14.7 ± 6.5 mm. CAMEUS better correlated with the presence of non-alcoholic fatty liver disease (NAFLD) (R2 = 0.248, P < 0.001) than BMI (R2 = 0.153, P < 0.001), and significantly correlated with metabolic parameters and diseases. After six months of intragastric balloon placement, the prospective cohort experienced 11.7% total body weight loss, 1.3 points improvement in hemoglobin A1c (P = 0.001), and a 29.4% average decrease in CAMEUS (-6.4 ± 5.2 mm, P < 0.001). CAMEUS correlated with improvements in weight (R2 = 0.368), aspartate aminotransferase to platelet ratio index (R2 = 0.138), and NAFLD activity score (R2 = 0.156) (all P < 0.05).

Conclusions

CAMEUS is a novel measure that is significantly correlated with critical metabolic indices and can be easily captured during routine EUS to risk-stratify susceptible patients. This station could allow for EUS access to sampling and therapeutics of this metabolic region.

Can Surgeons Reliably Identify Non-cirrhotic Liver Disease During Laparoscopic Bariatric Surgery?

INTRODUCTION

Identification of liver disease during bariatric operations is an important task given the patients risk for occult fatty liver disease. Surgeon's accuracy of assessing for liver disease during an operation is poorly understood. The objective was to measure surgeons' performance on intra-operative visual assessment of the liver in a simulated environment.

METHODS

Liver images from 100 patients who underwent laparoscopic bariatric surgery and pre-operative ultrasound elastography between July 2020 and July 2021 were retrospectively evaluated. The perception of 15 surgeons regarding the degree of hepatic steatosis and fibrosis was collected in a simulated clinical environment by survey and compared to results determined by ultrasonographic exam.

RESULTS

The surgeons' ability to correctly identify the class of steatosis and fibrosis was poor (accuracy 61% and 59%, respectively) with a very weak correlation between the surgeon's predicted class and its true class (r = 0.17 and r = 0.12, respectively). When liver disease was present, surgeons completely missed its presence in 26% and 51% of steatosis and fibrosis, respectively. Digital image processing demonstrated that surgeons subjectively classified steatosis based on the "yellowness" of the liver and fibrosis based on texture of the liver, despite neither correlating with the true degree of liver disease.

CONCLUSION

Laparoscopic visual assessment of the liver surface for identification of non-cirrhotic liver disease was found to be an inaccurate method during laparoscopic bariatric surgery. While validation studies are needed, the results suggest the clinical need for alternative approaches.

How best to combine liver transplantation and bariatric surgery?-Results from a global, web-based survey

BACKGROUND AND AIMS

Obesity is a growing healthcare challenge worldwide and a significant risk factor for liver failure as seen with non-alcoholic steatohepatitis (NASH). Combining metabolic-bariatric surgery (MBS) with liver transplantation (LT) appears as attractive strategy to treat both, the underlying liver disease and obesity. However, there is an ongoing debate on best timing and patient selection. This survey was designed to explore the current treatment practice for patients with NASH and obesity worldwide.

METHODS

A web-based survey was conducted in 2022 among bariatric and LT surgeons, and hepatologists from Europe, North and South America and Asia.

RESULTS

The survey completion rate was 74% (145/196). The average respondents were 41-50 years (38%), male (82.1%) and had >20 years of clinical experience (42.1%). Centres with a high LT-caseload for NASH were mainly located in the USA and United Kingdom. Almost 30% have already performed a combination of LT with MBS and 49% plan to do it. A majority of bariatric surgeons prefer MBS before LT (77.2%), whereas most of LT surgeons (52%) would perform MBS during LT. Most respondents (n = 114; 80%) favour sleeve gastrectomy over other bariatric techniques. One third (n = 42; 29.4%) has an established protocol regarding MBS for LT candidates.

CONCLUSION

The most experienced centres doing LT for NASH are in the USA and United Kingdom with growing awareness worldwide. Overall, a combination of MBS and LT has already been performed by a third of respondents. Sleeve gastrectomy is the bariatric technique of choice-preferably performed either before or during LT.

The Use of Noninvasive Scores in Predicting NAFLD Progression After Bariatric Surgery

BACKGROUND

Bariatric surgery has been postulated to impact liver function resulting in favorable effects on nonalcoholic fatty liver disease (NAFLD). We aimed to analyze the long-term impact of bariatric surgery on noninvasive scores predicting the progression of liver fibrosis in a bariatric population.

METHODS

We retrospectively reviewed the records of patients without pre-existing liver disease who underwent sleeve gastrectomy or Roux-en-Y gastric bypass (RYGB) at our center between 2010 and 2018. Four predictive scores for liver fibrosis (AST/ALT, APRI, Fib-4, and BARD) were calculated preoperatively, 6 months post-operatively, and annually up to 5 years. Correlations were analyzed with Pearson R. Subgroup and sensitivity analyses were performed to identify populations at increased risk.

RESULTS

A total of 2769 patients were included. The mean age was 40 years, and the majority was females (88.5%) and of Hispanic ethnicity (59.2%). There was a steady post-operative increase in the percentage of patients at increased risk of progression of liver fibrosis. The Fib-4 score showed the largest increase in the population at risk for liver fibrosis (11.3% preoperatively to 28.9% at 5 years). Patients with diabetes and those who underwent a sleeve gastrectomy continued to display a higher risk for liver fibrosis than did patients without diabetes and those who underwent RYGB, respectively.

CONCLUSION

There was an overall trend to increased liver fibrosis scores over the 5-year post-operative follow-up, but this increase remained lower than that reported in previous literature. Bariatric surgery offers NAFLD risk reduction in a high-risk population.

Pharmaceutical Strategies to Improve Druggability of Potential Drug Candidates in Nonalcoholic Fatty Liver Disease Therapy

Nonalcoholic fatty liver disease (NAFLD) has become globally prevalent and is the leading cause of chronic liver disease. Although NAFLD is reversible without medical intervention in the early stage, the condition could be sequentially worsened to nonalcoholic steatohepatitis (NASH) and, eventually, cirrhosis and hepatic cancer. The progression of NAFLD is related to various factors such as genetics, pre-disposed metabolic disorders, and immunologic factors. Thankfully, to date, there have been accumulating research efforts and, as a result, different classes of potent drug candidates have been discovered. In addition, there have also been various attempts to explore pharmaceutical strategies to improve the druggability of drug candidates. In this review, we provided a brief overview of the drug candidates that have undergone clinical trials. In the latter part, strategies for developing better drugs are discussed.

CRISPR/Cas9-Based Screening of FDA-Approved Drugs for NRF2 Activation: A Novel Approach to Discover Therapeutics for Non-Alcoholic Fatty Liver Disease

With the rising prevalence of obesity, non-alcoholic fatty liver disease (NAFLD) now affects 20-25% of the global population. NAFLD, a progressive condition associated with oxidative stress, can result in cirrhosis and liver cancer in 10% and 3% of patients suffering NAFLD, respectively. Therapeutic options are currently limited, emphasizing the need for novel treatments. In this study, we examined the potential of activating the transcription factor NRF2, a crucial player in combating oxidative stress, as an innovative approach to treating NAFLD. Utilizing a CRISPR/Cas9-engineered human HEK293T cell line, we were able to monitor the expression of heme oxygenase-1 (HMOX1), an NRF2 target, using a Nanoluc luciferase tag. Our model was validated using a known NRF2 activator, after which we screened 1200 FDA-approved drugs, unearthing six compounds (Disulfiram, Thiostrepton, Auranofin, Thimerosal, Halofantrine, and Vorinostat) that enhanced NRF2 activity and antioxidant response. These compounds demonstrated protective effects against oxidative stress induced by hydrogen peroxide and lipid droplets accumulation in vitro with hepatoma HUH-7 cells. Our study underscores the utility of CRISPR/Cas9 tagging with Nanoluc luciferase in identifying potential NRF2 activators, paving the way for potential NAFLD therapeutics.

Screening strategy for non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, affecting approximately 25% of the general population worldwide, and is forecasted to increase global health burden in the 21st century. With the advancement of non-invasive tests for assessing and monitoring of steatosis and fibrosis, NAFLD screening is now feasible, and is increasingly highlighted in international guidelines related to hepatology, endocrinology, and pediatrics. Identifying high-risk populations (e.g., diabetes mellitus, obesity, metabolic syndrome) based on risk factors and metabolic characteristics for non-invasive screening is crucial and may aid in designing screening strategies to be more precise and effective. Many screening modalities are currently available, from serum-based methods to ultrasonography, transient elastography, and magnetic resonance imaging, although the diagnostic performance, cost, and accessibility of different methods may impact the actual implementation. A two-step assessment with serum-based fibrosis-4 index followed by imaging test vibration-controlled transient elastography can be an option to stratify the risk of liverrelated complications in NAFLD. There is a need for fibrosis surveillance, as well as investigating the cost-effectiveness of different screening algorithms and engaging primary care for first-stage triage screening.

One-anastomosis gastric bypass reversal due to severe malnutrition and acute hepatic failure: a case report

The one-anastomosis gastric bypass (OAGB) is one of the most popular performed bariatric surgeries and has good long-term success for treating obesity and metabolic diseases. However, some patients can develop severe complications such as malnutrition and hepatic steatosis, which can be corrected with a reversal procedure, as seen in this case. A 20-year-old woman underwent OAGB surgery, which was converted to Roux-en-Y gastric bypass 4 months after the initial procedure due to malnutrition, both surgeries were performed at a hospital in southern Mexico. After the second surgery, she presented to our hospital with intolerance to oral feeding, vomiting and loss of 44 kg in 4 months. The patient was stabilized and scheduled for reversion surgery to normal anatomy 5 months later. She had good short-term nutritional outcomes and at the 1-year follow-up her total weight gain was 14 kg.

Low-Grade Hepatic Steatosis Is Associated with Long-term Remission of Type 2 Diabetes Independent of Type of Bariatric-Metabolic Surgery

BACKGROUND

Bariatric-metabolic surgery (BS) decreases the grade of steatosis, hepatic inflammation, and fibrosis in patients with severe obesity and non-alcoholic fatty liver disease (NAFLD). Mechanisms include substantial weight loss, but also simultaneous effects on glucose homeostasis. Therefore, we aimed to investigate the association between NAFLD and remission of type 2 diabetes (T2D) up to 8 years following different types of BS.

METHODS

In a retrospective cohort study including 107 patients with obesity and T2D at baseline, the association between biopsy-proven NAFLD defined as steatosis in > 5% of hepatocytes at the time of surgery and T2D remission up to 8 years following different surgical procedures was investigated. Univariate regression analysis was used to examine the association between NAFLD and remission of T2D.

RESULTS

Long-term remission of T2D was present in 56% of patients (n = 60). The presence of low-grade liver steatosis (grade 1) was associated with remission of T2D. Patients with a liver steatosis score ≥ 2 showed higher HbA1c levels at baseline. There were no significant differences in preoperative presence of lobular inflammation, hepatocyte ballooning, or fibrosis between patients who achieved T2D remission compared with those with no remission. Type of surgery did not affect remission of T2D.

CONCLUSION

Our results suggest that the presence of low-grade liver steatosis is associated with remission of T2D following sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB). Therefore, BS should be considered at an early NAFLD stage in patients with T2D.

Real-time elastography “FibroScan” compared to simple non-invasive screening tools in the assessment of liver fibrosis in non-alcoholic fatty liver patients

Background and aim

Non-alcoholic fatty liver disease (NAFLD) and its subtype non-alcoholic steatohepatitis (NASH) are increasing worldwide. NASH is characterized by active liver inflammation with severe consequences including progressive fibrosis, cirrhosis, and eventually hepatocellular carcinoma. In Egypt, the prevalence of NAFLD diagnosed by ultrasound is about 65.3% in children and 62.7% in adults. Liver biopsy, the only reliable method of differentiating simple steatosis from NASH, has a major disadvantage of being an invasive procedure with various complications. Serum tests have limitations including non-specificity for liver inflammation and affection by clearance rates. This study aimed to assess the reliability of simple non-invasive tests for liver fibrosis (namely fibrosis-4 “FIB-4” score and NAFLD fibrosis score) in comparison with real-time elastography (RTE or FibroScan) in patients diagnosed with NAFLD.

Patients and methods

This observational prospective case–control study was conducted on 100 cases with NAFLD and 30 healthy subjects. All patients and controls were subjected to serological (FIB-4 score and NAFLD fibrosis score) and radiological (ultrasonography and RTE) assessments of liver fibrosis.

Results

In advanced FIB-4 score ≥ F3, there was a good correlation between the findings of the RTE and each of the FIB-4 scores (with a sensitivity of 90%, specificity of 93.3%, positive predictive value (PPV) of 60%, negative predictive value (NPV) of 98.8%, with a total accuracy of 93%), NAFLD fibrosis score (with a sensitivity of 52.6%, specificity of 93.8%, PPV of 66.7%, NPV of 89.4%, with a total accuracy of 86%), and grading of steatosis by ultrasound.

Conclusions

RTE is beneficial in diagnosing and assessing NAFLD, especially in advanced cases “F3 and beyond.”

Identification of a Fatty Acid for Diagnosing Non-Alcoholic Steatohepatitis in Patients with Severe Obesity Undergoing Metabolic Surgery

The prevalence of nonalcoholic steatohepatitis (NASH) in severely obese Japanese patients is extremely high. However, there are currently no methods other than liver biopsy to assess hepatic steatosis and fibrosis. The purpose of this study was to comprehensively analyze changes in fatty acid (FA) and serum-free fatty acid (FFA) metabolism in severely obese Japanese patients to determine whether these could be surrogate markers. In this study, we enrolled 20 Japanese patients who underwent laparoscopic sleeve gastrectomy (LSG) for severe obesity and intraoperative liver biopsy. Serum FFAs were analyzed with liquid chromatography-mass spectrometry, and FAs in liver tissue were assessed using matrix-assisted laser desorption/ionization-imaging mass spectrometry to determine FAs that may be indicative of a positive NASH diagnosis. All patients showed significant weight loss and metabolic improvement following LSG. Regarding weight loss and metabolic improvement indices, 23 FFAs showed significant correlations with the baseline data. Narrowing down the phospholipids to commonly detected FAs detected in liver tissue, PC(18:1e_20:4) was significantly changed in the NASH group, suggesting that it could be used as a surrogate marker for NASH diagnosis. The results suggest that specific postoperative changes in blood phospholipids could be used as surrogate markers for NASH treatment.

Deletion of Smurf1 attenuates liver steatosis via stabilization of p53

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease, characterized by excessive hepatic lipid accumulation. Recently, we demonstrated that Smad ubiquitination regulatory factor 1 (Smurf1) deficiency significantly alleviates mouse hepatic steatosis. However, the mechanism of Smurf1-regulating hepatic lipid accumulation requires further exploration and clarification. Hence, this study explores the potential mechanism of Smurf1 in hepatic steatosis. In this study, hepatic Smurf1 proteins in NAFLD patients and healthy individuals were determined using immunohistochemical staining. Control and NAFLD mouse models were established by feeding Smurf1-knockout (KO) and wild-type mice with either a high-fat diet (HFD) or a chow diet (CD) for eight weeks. Oleic acid (OA)-induced steatotic hepatocytes were used as the NAFLD mode cells. Lipid content in liver tissues was analyzed. Smurf1-MDM2 interaction, MDM2 and p53 ubiquitination, and p53 target genes expression in liver tissues and hepatocytes were analyzed. We found that hepatic Smurf1 is highly expressed in NAFLD patients and HFD-induced NAFLD mice. Its deletion attenuates hepatocyte steatosis. Mechanistically, Smurf1 interacts with and stabilizes mouse double minute 2 (MDM2), promoting p53 degradation. In Smurf1-deficient hepatocytes, an increase in p53 suppresses SREBP-1c expression and elevates the expression of both malonyl-CoA decarboxylase (MCD) and lipin1 (Lpin1), two essential proteins in lipid catabolism. Contrarily, the activities of these three proteins and hepatocyte steatosis are reversed by p53 knockdown in Smurf1-deficient hepatocytes. This study shows that Smurf1 is involved in the pathogenesis of NAFLD by balancing de novo lipid synthesis and lipolysis.

Long-Term Outcomes Associated with NAFLD, ASCVD, and All-Cause Mortality of Patients with Metabolic Syndrome

Metabolic syndrome (MetS) patients are at higher risk for nonalcoholic fatty liver disease (NAFLD), atherosclerotic cardiovascular diseases (ASCVD), and death. Given a lack of longitudinal data on patients with MetS in Southeast Asia, this study investigated the incidence of NAFLD and ASCVD and the all-cause mortality rate during a 10-year follow-up of Thai patients with MetS. Retrospective data were collected on 496 MetS patients with ultrasonography or transient elastography results. The patients had been followed up continuously by a university hospital between October 2011 and November 2021, and their mean age was 61.0 ± 10.9 years. Patients with secondary causes of hepatic steatosis were excluded. Cox proportional hazards regression models with time-varying covariates were adopted. During the 10-year follow-up, 17 patients (11.2%) developed NAFLD, and 27 (6.4%) developed ASCVD. The NAFLD and ASCVD incidence rates were 21.7 and 10.9 events per 1000 person years, respectively. The mortality rate was 14.2 deaths per 1000 person years. The prevalence of hypertension, dyslipidemia, ASCVD, NAFLD, advanced fibrosis, and cirrhosis at baseline was significantly higher in the nonsurvival group. The NAFLD incidence and mortality rate of patients with MetS were lower than those in previous studies. Intensive, holistic, and continuous care should be considered for better outcomes.

The impact of health status, diet and lifestyle on non-alcoholic fatty liver disease: Narrative review

Non-alcoholic fatty liver disease (NAFLD) is defined as the abnormal accumulation of triglycerides in the liver. NAFLD has a global prevalence of almost 30%, while incidence is rising with increasing levels of obesity, type 2 diabetes mellitus (T2DM) and metabolic syndrome. Nutrition plays a significant role in both the prevention and treatment of NAFLD. Therefore, the aim of this literature review is to explore the associations between dietary, lifestyle and other risk factors and the risk for developing NAFLD. Dietary patterns, lifestyle behaviours, comorbidities, or a combination of any may contribute to either the progression or prevention of NAFLD. Having diabetes, hypertension, or having obesity might increase the progression of NAFLD if not well treated and controlled. Diet influences the progression of NAFLD; following a western diet or simply a high-fat diet may contribute to the worsening of NAFLD and further progression to non-alcoholic steatohepatitis (NASH) and cirrhosis in later stages. On the other hand, the Mediterranean diet is the gold standard for both the treatment and prevention of NAFLD. Social behaviours, such as smoking, caffeine consumption and physical activity also play a role in the pathophysiology of NAFLD. Nutrition contributes significantly to the prevention or treatment of NAFLD, since this disease can be managed by diet and physical activity. However, further studies are still needed for a better understanding of the mechanisms of action. Randomized control trials are also needed to confirm findings in observational studies.

Evaluation of nonalcoholic fatty liver disease (NAFLD) in severe obesity using noninvasive tests and imaging techniques

The prevalence of nonalcoholic fatty liver disease (NAFLD) and the more severe and inflammatory type, nonalcoholic steatohepatitis (NASH), is increasing rapidly. Especially in high-risk patients, that is those with obesity, metabolic syndrome, and type 2 diabetes mellitus, the prevalence of NAFLD can be as high as 80% while NASH may be present in 20% of these subjects. With the worldwide increase of obesity, it is most likely that these numbers will rise. Since advanced stages of NAFLD and NASH are strongly associated with morbidity and mortality-in particular, cardiovascular disease, liver cirrhosis, and hepatocellular carcinoma-it is of great importance to identify subjects at risk. A great variety of noninvasive tests has been published to diagnose NAFLD and NASH, especially using blood- and imaging-based tests. Liver biopsy remains the gold standard for NAFLD/NASH. This review aims to summarize the different mechanisms leading to NASH and liver fibrosis, the different noninvasive liver tests to diagnose and evaluate patients with severe obesity.

Metabolic-associated Fatty Liver Disease (MAFLD): A Multi-systemic Disease Beyond the Liver

Nonalcoholic fatty liver disease (NAFLD) is a multisystemic clinical condition that presents with a wide spectrum of extrahepatic manifestations, such as obesity, type 2 diabetes mellitus, metabolic syndrome, cardiovascular diseases, chronic kidney disease, extrahepatic malignancies, cognitive disorders, and polycystic ovarian syndrome. Among NAFLD patients, the most common mortality etiology is cardiovascular disorders, followed by extrahepatic malignancies, diabetes mellitus, and liver-related complications. Furthermore, the severity of extrahepatic diseases is parallel to the severity of NAFLD. In clinical practice, awareness of the associations of concomitant diseases is of major importance for initiating prompt and timely screening and multidisciplinary management of the disease spectrum. In 2020, a consensus from 22 countries redefined the disease as metabolic (dysfunction)-associated fatty liver disease (MAFLD), which resulted in the redefinition of the corresponding population. Although the patients diagnosed with MAFLD and NAFLD mostly overlap, the MAFLD and NAFLD populations are not identical. In this review, we compared the associations of key extrahepatic diseases between NAFLD and MAFLD.

The National Consensus statement on the management of adult patients with non-alcoholic fatty liver disease and main comorbidities

The National Consensus was prepared with the participation of the National Medical Association for the Study of the Multimorbidity, Russian Scientific Liver Society, Russian Association of Endocrinologists, Russian Association of Gerontologists and Geriatricians, National Society for Preventive Cardiology, Professional Foundation for the Promotion of Medicine Fund PROFMEDFORUM. The aim of the multidisciplinary consensus is a detailed analysis of the course of non-alcoholic fatty liver disease (NAFLD) and the main associated conditions. The definition of NAFLD is given, its prevalence is described, methods for diagnosing its components such as steatosis, inflammation and fibrosis are described. The association of NAFLD with a number of cardio-metabolic diseases (arterial hypertension, atherosclerosis, thrombotic complications, type 2 diabetes mellitus (T2DM), obesity, dyslipidemia, etc.), chronic kidney disease (CKD) and the risk of developing hepatocellular cancer (HCC) were analyzed. The review of non-drug methods of treatment of NAFLD and modern opportunities of pharmacotherapy are presented. The possibilities of new molecules in the treatment of NAFLD are considered: agonists of nuclear receptors, antagonists of pro-inflammatory molecules, etc. The positive properties and disadvantages of currently used drugs (vitamin E, thiazolidinediones, etc.) are described. Special attention is paid to the multi-target ursodeoxycholic acid (UDCA) molecule in the complex treatment of NAFLD as a multifactorial disease. Its anti-inflammatory, anti-oxidant and cytoprotective properties, the ability to reduce steatosis an independent risk factor for the development of cardiovascular pathology, reduce inflammation and hepatic fibrosis through the modulation of autophagy are considered. The ability of UDCA to influence glucose and lipid homeostasis and to have an anticarcinogenic effect has been demonstrated. The Consensus statement has advanced provisions for practitioners to optimize the diagnosis and treatment of NAFLD and related common pathogenetic links of cardio-metabolic diseases.

Non-Alcoholic Fatty Liver Disease (NAFLD) and Bariatric/Metabolic Surgery as Its Treatment Option: A Review

The prevalence of non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) has considerably increased over the last years. NAFLD is currently the most common cause of chronic liver disease in the developing world. The diagnosis of NAFLD/NASH is often incidental, as the early-stage of disease is frequently free of symptoms. Most patients recognized with NAFLD have severe obesity and other obesity-related disease such as type 2 diabetes mellitus (T2DM), insulin-resistance, dyslipidemia and hypertension. The only proven method for NAFLD improvement and resolution is weight loss. Bariatric surgery leads to significant and long-term weight loss as well as improvement of coexisting diseases. There is a lot of evidence suggesting that metabolic/bariatric surgery is an effective method of NAFLD treatment that leads to reduction in steatosis, hepatic inflammation and fibrosis. However, there is still a need to perform long-term studies in order to determine the role of bariatric surgery as a treatment option for NAFLD and NASH. This review discusses current evidence about epidemiology, pathogenesis and treatment options for NAFLD including bariatric/metabolic surgery and its effect on improvement and resolution of NAFLD.

Accuracy of non-invasive liver stiffness measurement and steatosis quantification in patients with severe and morbid obesity

Background

Vibration controlled transient elastography (VCTE) and controlled attenuation parameter (CAP™) have shown reliable performance predicting fibrosis and steatosis in normal- to overweight patients but have not been validated in severe to morbid obesity. This study aimed at determining the accuracy of VCTE, CAP™ and the composite score FibroScan-AST (FAST) in patients with a body mass index (BMI) of ≥35 kg/m².

Methods

Patients scheduled for bariatric-metabolic surgery underwent preoperative VCTE/CAP™ measurement, and intraoperative liver biopsy. The feasibility and accuracy of VCTE, CAP™ and the composite score FAST were retrospectively analysed to evaluate fibrosis, steatosis and active fibrotic non-alcoholic steatohepatitis [NASH + non-alcoholic fatty liver disease (NAFLD) activity score ≥4 + fibrosis grade ≥2] using per protocol (PP) and intent to diagnose (ITD) calculation.

Results

In total, 170 patients (median BMI 44.4 kg/m²) were included in the study. Liver biopsy showed NASH, simple steatosis, and normal livers in 60.6% (n=103), 28.8% (n=49), and 10.6% (n=18), respectively. VCTE and CAP™ delivered reliable results in 90.6% (n=154/170) and 90.5% (n=134/148). The AUC (PP) of VCTE, CAP™, and FAST were 0.687 (≥F2), 0.786 (≥F3), 0.703 (≥S2), 0.738 (S3), and 0.780 (active fibrotic NASH). The AUC increased to 0.742 (≥F2), 0.842 (≥F3), 0.712 (≥S2), 0.780 (S3), and 0.836 (active fibrotic NASH) in patients below the median BMI of 44.4 kg/m².

Conclusions

VCTE, CAP™ and FAST show acceptable accuracy for the detection of fibrosis, steatosis and NASH in a real-life cohort of patients with obesity. Accuracy improves in patients with a BMI <44.4 kg/m².

"Bioelectrical impedance analysis in managing sarcopenic obesity in NAFLD"

INTRODUCTION

Sarcopenic obesity and its association with nonalcoholic fatty liver disease (NAFLD) is under-recognized by many healthcare providers in Western medicine due to the lack of awareness and diagnostic guidelines. The result is delayed recognition and treatment, which leads to further health deterioration and increased healthcare costs. Sarcopenic obesity is characterized by the presence of increased fat mass in combination with muscle catabolism related to chronic inflammation and/or inactivity. Previous research has recommended evaluating body composition and physical function performance to adequately diagnose sarcopenic obesity. Body composition analysis can be performed by imaging applications through magnetic resonance imaging, computed tomography, and dual-energy x-ray absorptiometry. Due to the cost of each device and radiation exposure for patients as evidenced in all three modalities, bioelectrical impedance analysis offers a noninvasive approach capable of providing quick and reliable estimates of lean body and fat mass.

METHODS AND RESULTS

This review analyzes the current evidence-based literature, indicating a lower skeletal muscle mass and increased visceral adipose tissue correlation to the advancement of fibrosis in fatty liver disease.

CONCLUSION

Given the substantial promising research conducted in predominantly Asian populations regarding body tissue distribution and NAFLD, additional prospective research is needed to extend these findings in Western populations.

Bariatric Surgery and Liver Disease: General Considerations and Role of the Gut-Liver Axis

Weight loss is a therapeutic solution for many metabolic disorders, such as obesity and its complications. Bariatric surgery aims to achieve lasting weight loss in all patients who have failed after multiple dietary attempts. Among its many benefits, it has been associated with the regression of non-alcoholic fatty liver disease (NAFLD), which is often associated with obesity, with evidence of substantial improvement in tissue inflammation and fibrosis. These benefits are mediated not only by weight loss, but also by favorable changes in systemic inflammation and in the composition of the gut microbiota. Changes in microbial metabolites such as short-chain fatty acids (SCFAs), capable of acting as endocrine mediators, and bile acids (BAs) as well as modifications of the gut-brain axis, are among the involved mechanisms. However, not all bariatric surgeries show beneficial effects on the liver; those leading to malabsorption can cause liver failure or a marked worsening of fibrosis and the development of cirrhosis. Nevertheless, there are still many unclear aspects, including the extent of the benefits and the magnitude of the risks of bariatric surgery in cirrhotic patients. In addition, the usefulness and the safety of these procedures in patients who are candidates to or who have undergone liver transplant need solid supporting evidence. This paper aims to review literature data on the use of bariatric surgery in the setting of chronic liver disease.

The Evolving Role of Fetuin-A in Nonalcoholic Fatty Liver Disease: An Overview from Liver to the Heart

Nonalcoholic fatty liver disease (NAFLD) is strongly associated to the features of metabolic syndrome which can progress to cirrhosis, liver failure and hepatocellular carcinoma. However, the most common cause of mortality in people with NAFLD is not liver-related but stems from atherosclerotic cardiovascular disease (CVD). The prevalence of NAFLD is on the rise, mainly as a consequence of its close association with two major worldwide epidemics, obesity and type 2 diabetes (T2D). The exact pathogenesis of NAFLD and especially the mechanisms leading to disease progression and CVD have not been completely elucidated. Human fetuin-A (alpha-2-Heremans Schmid glycoprotein), a glycoprotein produced by the liver and abundantly secreted into the circulation appears to play a role in insulin resistance, metabolic syndrome and inflammation. This review discusses the links between NAFLD and CVD by specifically focusing on fetuin-A’s function in the pathogenesis of NAFLD and atherosclerotic CVD.

Effect of bariatric surgery on fatty liver disease in obese patients: A prospective one year follow-up study

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD), often associated with obesity and metabolic syndrome, manifests itself as steatosis, hepatic fibrosis, cirrhosis, or even end-stage liver disease. NAFLD causes inflammation, insulin resistance and cardiovascular complications. The current study aimed to evaluate the beneficial effects of bariatric surgery on biochemical parameters of hepatic functions in obese patients by comparing them before and one-year after the surgery.

METHODS

A total of 72 morbidly obese patients underwent bariatric surgery between 2016 and 2018. The incidence of diabetes mellitus in this group was 29%, median body weight was 124.5 kg (109.0-140.0) and mean body mass index (BMI) was 44.38 ± 6.770 kg/m². The used surgical procedures included gastric bypass, sleeve gastrectomy, laparoscopic gastric plication, and single anastomosis duodeno-ileal bypass-sleeve gastrectomy. Biochemical parameters including ALT/AST ratio (AAR), NAFLD fibrosis score (NFS), hepatic fibrosis index (FIB-4) and Fatty Liver Index (FLI) were evaluated in all patients at the time of surgery and one year after the intervention.

RESULTS

Significant improvement after the intervention was observed in 64 patients. A significant reduction in body weight (P<0.0001), waist circumference (P<0.0001), and body mass index (P<0.0001) were observed. NAFLD liver fibrosis index changed significantly (P<0.0001), suggesting a trend of improvement from advanced fibrosis towards stages 0-2. The FIB-4 fibrosis index indicated significant improvement (P=0.0136). Besides, a significant decline in hepatic steatosis (P<0.0001) was observed after bariatric surgery as compared to the pre-surgery fatty liver conditions.

CONCLUSION

Among the strategies to overcome NAFLD-associated impediments, bariatric surgery can be considered effective in reducing obesity and metabolic co-morbidities.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT04569396).

NAFLD: a multi-faceted morbid spectrum with uncertain diagnosis and complicated management. Where do we stand? Review of the literature

NASH can be considered the "contemporary era pandemic", because of its global widespread in parallel with obesity, diabetes and metabolic dysfunction. It is a disease that often poses many difficulties, since making a early diagnosis is often impossible since specific diagnostic tests and criteria are missing: so, it needs a high degree of suspicion. Most of the times the evolution to its more severe and terminal step, NASH cirrhosis, is unavoidable and so are the social pressure on health sistem and economic consequences it brings back. In this work we aim to review the literature about both NAFLD and NASH, thus structuring a wide, comprehensive, 360 degree work with a focus on all major aspects of NAFLD, spanning from diagnosis, physiopathology and its repercussions on liver transplantation. Moreover we also focused on patients related issues both in pre- and post-transplant management (when these patients are listed for liver transplant). NAFLD and NASH are a contemporary plague, and an exaustive knowledge of the problem throughout all its aspects is necessary in order to lower economic weight that metabolic issues bring back and to have a open view to possible solutions to all management issues that NASH patients have and that are oten prohibitive to a definitive cure (for example cardiovascular risk in patients otherwise eligible to liver transplantation). We aim to offer a complete view on the actual knowledge about NAFLD and NASH, by an extensive review of the literature.

Evaluation of Liver Function Tests and Risk Score Assessment to Screen Patients for Significant Liver Disease Prior to Bariatric and Metabolic Surgery

Bariatric and metabolic surgery is associated with significant improvement in obesity-related comorbidities, but for patients with non-alcoholic fatty liver disease (NAFLD), clinical outcomes are dependent on the severity of liver disease, i.e. improvement of NAFLD in most patients but increased risks of fulminant hepatic failure and/or bleeding varices in patients with more advanced cirrhosis. Our study showed that absolute values of liver enzymes were poor indicator of risk of liver fibrosis. The use of AST/ALT ratio, Fib 4 or NAFLD scores were appropriate screening tools, with each risk score appearing to pick out a certain phenotype of patients based on age, BMI or individual values of ALT, AST or platelet count. There is lack of agreement in some cases between FIB-4 scores and NAFLD scores when ruling out patients at high risk of liver fibrosis. Meticulous screening of patients at risk of liver fibrosis is crucial in order to reduce the risk of liver-related complications following bariatric and metabolic surgery.

Nonalcoholic Fatty Liver Disease in Lean Subjects: Associations With Metabolic Dysregulation and Cardiovascular Risk-A Single-Center Cross-Sectional Study

INTRODUCTION

Although a milder metabolic phenotype of nonalcoholic fatty liver disease (NAFLD) in lean patients (body mass index [BMI] <25 kg/m2) compared to overweight/obese patients with NAFLD is assumed, the relevance of NAFLD among lean subjects remains a matter of debate. We aimed to characterize the metabolic/cardiovascular phenotype of lean patients with NAFLD.

METHODS

In total, 3,043 subjects (cohort I) and 1,048 subjects (cohort II) undergoing screening colonoscopy between 2010 and 2020 without chronic liver disease other than NAFLD were assigned to one of the following groups: lean patients without NAFLD, lean NAFLD, overweight NAFLD (BMI 25-30 kg/m2), and obese NAFLD (BMI >30 kg/m2). Diagnosis of NAFLD was established using ultrasound (cohort I) and controlled attenuation parameter (cohort II).

RESULTS

The prevalence of lean patients with NAFLD was 6.7%/16.1% in the overall cohort I/II and 19.7%/40.0% in lean subjects of cohort I/II. Compared with lean subjects without NAFLD, lean patients with NAFLD had a higher prevalence of dyslipidemia, dysglycemia, and the metabolic syndrome, together with a higher median Framingham risk score in both cohorts (all P < 0.001). On multivariable analyses, NAFLD in lean subjects was associated with higher odds of metabolic syndrome (adjusted odds ratio cohort I: 4.27 [95% confidence interval (CI): 2.80-6.51], P < 0.001; cohort II: 2.97 [95% CI: 1.40-6.33], P < 0.001), and higher Framingham risk score (regression coefficient B cohort I: 1.93 [95% CI: 0.95-2.92], P < 0.003; cohort II: 1.09 [95% CI: 0.81-2.10], P = 0.034), among others. Only 69.8% of lean patients with NALFD in cohort I and 52.1% in cohort II fulfilled the novel criteria for metabolic associated fatty liver disease.

DISCUSSION

NAFLD in lean patients is associated with the metabolic syndrome and increased cardiovascular risk. Novel metabolic associated fatty liver disease criteria leave a considerable proportion of patients unclassified.

Serum Glycocholic Acid-to-Total Bile Acid Ratio Is Independently Associated with Nonalcoholic Fatty Liver Disease: A Retrospective Cross-Sectional Study

Introduction and Aims. Bile acids play an essential role in the progression of nonalcoholic fatty liver disease (NAFLD). This study was aimed at investigating the association of the serum glycocholic acid- (GCA-) to-total bile acid (TBA) ratio with NAFLD in the general population. Materials and Methods. A total of 6708 subjects (2859 cases with NAFLD and 3849 controls) were enrolled in the development cohort and additional 1568 subjects (784 cases with NAFLD and 784 controls) in an independent validation cohort. Demographic characteristics and biochemical data were compared between subjects with NAFLD and controls. Multivariate logistic regression analysis was performed to determine the association of the GCA-to-TBA ratio with NAFLD. A novel model incorporating the GCA-to-TBA ratio was developed for screening NAFLD from the general population. Results. The serum TBA and GCA levels were significantly higher in subjects with NAFLD than in those without NAFLD (2.8 (2.0-4.2) μmol/L vs. 2.5 (1.8-3.7) μmol/L and 1.30 (1.10-1.53) μg/mL vs. 1.28 (1.08-1.50) μg/mL, respectively, all $p\le 0.01$ ), whereas the serum GCA-to-TBA ratio was significantly lower in subjects with NAFLD than in subjects without NAFLD (0.44 (0.33-0.60) vs. 0.48 (0.36-0.64), $p\le 0.01$ ). Logistic regression analysis showed that the GCA-to-TBA ratio was independently associated with NAFLD after adjustment for confounding factors (odds ratio: 0.81, 95% confidence interval (CI): 0.71-0.92, $p\le 0.01$ ). The area under the receiver operating characteristic curve of the novel developed GCA-to-TBA ratio score model in discriminating NAFLD was 0.84 (95% CI: 0.83-0.85) in the development cohort and was 0.91 (95% CI: 0.36-0.65) in the validation cohort. Conclusion. The serum GCA-to-TBA ratio is independently associated with NAFLD. A simple novel model incorporating the GCA-to-TBA ratio score has a good performance in discriminating NAFLD from the general population.

Hsa_circ_0048179 attenuates free fatty acid-induced steatosis via hsa_circ_0048179/miR-188-3p/GPX4 signaling

Although circular RNAs (circRNAs) are known to play key roles in non-alcoholic fatty liver disease, much about their targets and mechanisms remains unknown. We therefore investigated the actions and mechanisms of hsa_circ_0048179 in an in vitro model of NAFLD. HepG2 cells were exposed to oleate/palmitate (2:1 ratio) for 24 h to induce intracellular lipid accumulation. Using CCK-8 assays, flow cytometry, fluorescence microscopy, western blotting, RT-qPCR, and Oil red O staining, we found that oleate/palmitate treatment reduced cell viability while increasing apoptosis and lipid accumulation in HepG2 cells. Levels of the antioxidant enzyme GPX4 were decreased in oleate/palmitate-treated HepG2 cells, and there were corresponding increases in reactive oxygen species and damage to mitochondrial cristae. Levels of hsa_circ_0048179 expression were also suppressed by oleate/palmitate treatment, and GPX4 levels were markedly increased in HepG2 cells following transfection with hsa_circ_0048179. Analysis of its mechanism revealed that hsa_circ_0048179 upregulated GPX4 levels by acting as a competitive “sponge” of miR-188-3p and that hsa_circ_0048179 attenuated oleate/palmitate-induced lipid accumulation in HepG2 cells by sponging miR-188-3p. Collectively, our findings suggest that hsa_circ_0048179 may play a key role in the pathogenesis of steatosis and may thus be a useful target for drug development.

Complications of Non-Alcoholic Fatty Liver Disease in Extrahepatic Organs

Non-alcoholic fatty liver disease (NAFLD) is now recognized as the most common chronic liver disease worldwide, along with the concurrent epidemics of metabolic syndrome and obesity. Patients with NAFLD have increased risks of end-stage liver disease, hepatocellular carcinoma, and liver-related mortality. However, the largest cause of death among patients with NAFLD is cardiovascular disease followed by extrahepatic malignancies, whereas liver-related mortality is only the third cause of death. Extrahepatic complications of NAFLD include chronic kidney disease, extrahepatic malignancies (such as colorectal cancer), psychological dysfunction, gastroesophageal reflux disease, obstructive sleep apnea syndrome, periodontitis, hypothyroidism, growth hormone deficiency, and polycystic ovarian syndrome. The objective of this narrative review was to summarize recent evidences about extrahepatic complications of NAFLD, with focus on the prevalent/incident risk of such diseases in patients with NAFLD. To date, an appropriate screening method for extrahepatic complications has not yet been determined. Collaborative care with respective experts seems to be necessary for patient management because extrahepatic complications can occur across multiple organs. Further studies are needed to reveal risk profiles at baseline and to determine an appropriate screening method for extrahepatic diseases.

ESPEN practical guideline: Clinical nutrition in liver disease

BACKGROUND

The Practical guideline is based on the current scientific ESPEN guideline on Clinical Nutrition in Liver Disease.

METHODS

It has been shortened and transformed into flow charts for easier use in clinical practice. The guideline is dedicated to all professionals including physicians, dieticians, nutritionists and nurses working with patients with chronic liver disease.

RESULTS

A total of 103 statements and recommendations are presented with short commentaries for the nutritional and metabolic management of patients with (i) acute liver failure, (ii) alcoholic steatohepatitis, (iii) non-alcoholic fatty liver disease, (iv) liver cirrhosis, and (v) liver surgery/transplantation. The disease-related recommendations are preceded by general recommendations on the diagnostics of nutritional status in liver patients and on liver complications associated with medical nutrition.

CONCLUSION

This practical guideline gives guidance to health care providers involved in the management of liver disease to offer optimal nutritional care.

NAFLD and liver transplantation: Disease burden, current management and future challenges

Non-alcoholic fatty liver disease (NAFLD), specifically its progressive form non-alcoholic steatohepatitis (NASH), represents the fastest growing indication for liver transplantation in Western countries. Diabetes mellitus, morbid obesity and cardiovascular disease are frequently present in patients with NAFLD who are candidates for liver transplantation. These factors require specific evaluation, including a detailed pre-surgical risk stratification, in order to improve outcomes after liver transplantation. Moreover, in the post-transplantation setting, the incidence of cardiovascular events and metabolic complications can be amplified by immunosuppressive therapy, which is a well-known driver of metabolic alterations. Indeed, patients with NASH are more prone to developing early post-transplant complications and, in the long-term, de novo malignancy and cardiovascular events, corresponding to higher mortality rates. Therefore, a tailored multidisciplinary approach is required for these patients, both before and after liver transplantation. Appropriate candidate selection, lifestyle modifications and specific assessment in the pre-transplant setting, as well as pharmacological strategies, adjustment of immunosuppression and a healthy lifestyle in the post-transplant setting, play a key role in correct management.

Optimization of Point-Shear Wave Elastography by Skin-to-Liver Distance to Assess Liver Fibrosis in Patients Undergoing Bariatric Surgery

BACKGROUND

Obesity is a primary limiting factor in liver stiffness measurement (LSM). The impact of obesity has always been evaluated in terms of body mass index (BMI), without studying the effects of skin-to-liver distance (SLD) on LSM. We studied the impact of SLD on LSM in a cohort of obese patients undergoing bariatric surgery and intra-operatory liver biopsy.

MATERIALS AND METHODS

299 patients underwent LSM by point-shear wave elastography (ElastPQ protocol), with two different ultrasound machines. SLD was measured as the distance between the skin and the liver capsule, perpendicular to where the region of interest (ROI) was positioned. We used the following arbitrary cut-offs: <5.7 kPa, F0-1; 5.7-7.99 kPa, F2; ≥8 kPa, F3-4.

RESULTS

We developed two logistic regression models using elastography-histology agreement (EHA) as the dependent variable and SLD as the independent variable. The model based on the second machine showed strongly more performant discriminative and calibration metrics (AIC 38.5, BIC 44.2, Nagelkerke Pseudo-R2 0.894, AUROC 0.90). The SLD cut-off value of 34.5 mm allowed a correct EHA with a sensitivity of 100%, a specificity of 93%, negative predictive value of 100%, positive predictive value of 87%, an accuracy of 96%, and positive likelihood ratio of 3.56.

CONCLUSION

The impact of SLD is machine-dependent and should be taken into consideration when interpreting LSM. We believe that our findings may serve as a reference point for appropriate fibrosis stratification by liver elastography in obese patients.

Clinical utility of transient elastography as an imaging tool to assess the short-term impact of laparoscopic sleeve gastrectomy, together with clinical and biochemical parameters and clinico-biochemical indices, on obese patients with nonalcoholic fatty liver disease: An Egyptian pilot study

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) is a metabolic liver disorder commonly attributed to fatty acid deposition that can induce hepatic necroinflammation, defined as nonalcoholic steatohepatitis (NASH). It is strongly associated with obesity. Laparoscopic sleeve gastrectomy (LSG) is a favorable surgical modality for the treatment of morbid obesity.

AIM

Our study evaluated the impact of LSG on patients with NAFLD and morbid obesity, 3 months after the operation, through clinical and biochemical characteristics, clinico-biochemical indices, and imaging parameters.

PATIENTS AND METHODS

Morbidly obese patients with NAFLD±NASH underwent LSG. They were thoroughly evaluated clinically (body weight, body mass index, waist circumference) and biochemically (transaminases and triglycerides), as well as through the fatty liver index (FLI), the hepatic steatosis index (HSI), and ultrasound elastography imaging studies (liver stiffness measurement [LSM] and the controlled attenuation parameter [CAP]), before and 3 months after the LSG.

RESULTS

Twenty-six obese patients with NAFLD underwent LSG that resulted in a significantly high reduction in all the parameters analyzed, except for liver transaminases.

CONCLUSION

LSG is considered an efficient surgical modality for the treatment of morbidly obese patients with NAFLD.

Resection of NAFLD-Associated HCC: Patient Selection and Reported Outcomes

Global prevalence of non-alcoholic fatty liver disease (NAFLD) has been growing in the last decades, especially in western countries, due to increased prevalence of diabetes, obesity or other components of metabolic syndrome. NAFLD recently became an important cause of hepatocellular carcinoma (HCC), even in non-cirrhotic patients. Patients with HCC-NAFLD are usually older, with more morbidities (especially cardiovascular diseases and metabolic disorders) and have advanced disease at the diagnosis due to the absence of surveillance, which is considered not cost-effective in patients without advanced fibrosis/cirrhosis, given the large prevalence of NAFLD in the general population. For these reasons, patients with HCC-NAFLD unlikely underwent curative treatments, and have been reported to have lower overall survival (OS) compared to individuals with HCC related to other aetiologies. However, this difference is not confirmed by data of patient subgroups who received curative treatment. In our review, we selected studies published over the past 8 years that analyse characteristics and outcomes of HCC-NAFLD patients who underwent surgery with the aim of identifying features that could predict outcomes and potential selection criteria. All the studies confirm that patients with HCC-NAFLD are older, with many comorbidities and that HCC occurs frequently even in non-cirrhotic livers. There is no agreement about intraoperative and perioperative complications. Regarding outcomes, all papers agree that patients with HCC in NAFLD who undergo surgery have a better OS compared to other aetiologies. Summarizing, surgery is a good curative option for patients with HCC-NAFLD, perhaps even better than transplantation in terms of OS. In this group of patients, it seems to be essential to evaluate cardio-pulmonary and general operative risk, in addition to the normal risk assessment related to liver function to avoid an underestimation, especially for patients without severe underlying fibrosis.

Body Fat Changes and Liver Safety in Obese and Overweight Women Supplemented with Conjugated Linoleic Acid: A 12-Week Randomised, Double-Blind, Placebo-Controlled Trial

Preliminary evidence suggests that conjugated linoleic acid (CLA) may reduce body weight and affect body composition. The present study assessed the effect of CLA supplementation on body fat composition in overweight and obese women, while also evaluating the liver safety of CLA use. Seventy-four obese or overweight women were randomly assigned to receive 3 g/day CLA or placebo for 12 weeks. Body composition (dual-energy X-ray absorptiometry) and liver function (¹³C-methacetin breath test and serum liver enzymes) were assessed before and after the trial. Patients receiving CLA experienced a significant reduction of total body fat expressed as mass (p = 0.0007) and percentage (p = 0.0006), android adipose tissue (p = 0.0002), gynoid adipose tissue (p = 0.0028), and visceral adipose tissue (p = 4.2 × 10⁻⁹) as well as a significant increase in lean body mass to height (p = 6.1 × 10⁻¹¹) when compared to those receiving a placebo. The maximum momentary 13C recovery changes and end-point values were significantly higher in the CLA group when compared to the placebo group (p = 0.0385 and p = 0.0076, respectively). There were no significant changes in alanine aminotransferase, asparagine aminotransferase, and gamma-glutamyl transpeptidase activities between the groups. In conclusion, CLA supplementation was well tolerated and safe for the liver, which shows beneficial effects on fat composition in overweight and obese women.

Nonalcoholic Fatty Liver Disease 2020: The State of the Disease

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease, with a worldwide prevalence of 25%. In the United States, NAFLD and its subtype, nonalcoholic steatohepatitis, affect 30% and 5% of the population, respectively. Considering the ongoing obesity epidemic beginning in childhood, the rise in diabetes, and other factors, the prevalence of NAFLD along with the proportion of those with advanced liver disease is projected to continue to increase. This will have an important impact on public health reflected in health care costs, including impact on the need for liver transplantation, for which nonalcoholic steatohepatitis is already close to becoming the most common indication. NAFLD patients with evidence of nonalcoholic steatohepatitis and advanced fibrosis are at markedly increased risk of adverse outcomes, including overall mortality, and liver-specific morbidity and mortality, respectively. Identification of this cohort of NAFLD patients is paramount, given the associated poorer outcomes, in order to target resources to those who need it most. Various noninvasive tools have been developed in this regard. This review provides an update on the epidemiology, clinical and prognostic features, and diagnostic approach to patients with NAFLD.

Is bariatric surgery resolving NAFLD via microbiota-mediated bile acid ratio reversal? A comprehensive review

Despite the fact that there is still insufficient evidence to consider non-alcoholic fatty liver disease (NAFLD) as an stand-alone indication for bariatric surgery, many clinical and histopathological beneficial effects on both NAFLD and non-alcoholic steatohepatitis (NASH) have been shown. Although weight loss seems to be the obvious mechanism, weight-loss independent factors are also believed to be involved. Among them, changes in gut microbiota and bile acids (BA) composition may be playing an unappreciated role in the improvement of NAFLD. In this review we examine the mechanisms and interdependence of the gut microbiota and BA, and their influence on NAFLD pathogenesis and its reversal following bariatric surgery. According to the currently available evidence, gut microbiota has a major influence on BA composition. In fact, both BA and microbiome disturbances (dysbiosis) play a role in the etiopathogenesis of NAFLD and might be potential therapeutic targets. In addition, bariatric surgery can modify the intraluminal ileal environment in a way that causes significant repopulation of the gut microbiota and a reversal of the plasma primary/secondary BA ratio, which, in turn, induces weigh-independent metabolic improvements.

Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is considered the hepatic manifestation of the metabolic syndrome (MetS) and comprises one of the largest health threats of the twenty-first century. In this chapter, we review the current state of knowledge of NAFLD and underline the striking similarities with atherosclerosis. We first describe current epidemiological data showing the staggering increase of NAFLD numbers and its related clinical and economic costs. We then provide an overview of pathophysiological hepatic processes in NAFLD and highlight the systemic aspects of NAFLD that point toward metabolic crosstalk between organs as an important cause of metabolic disease. Finally, we end by highlighting the currently investigated therapeutic approaches for NAFLD, which also show strong similarities with a range of treatment options for atherosclerosis.

Nonalcoholic Steatohepatitis After Liver Transplantation

Currently, nonalcoholic steatohepatitis (NASH) is the second leading indication for liver transplantation (LT), behind alcohol-related liver disease. After transplant, both recurrent and de novo nonalcoholic fatty liver disease are common; however, recurrence rates of NASH and advanced fibrosis are low. Identification of high-risk groups and optimizing treatment of metabolic comorbidities both before and after LT is paramount to maintaining a healthy allograft, especially with the additional consequences of longterm immunosuppression. In addition, NASH LT recipients are at an increased risk of cardiovascular events and malignancy, and their condition warrants a tailored approach to management. The optimal approach to NASH LT recipients including metabolic comorbidities management, tailored immunosuppression, the role of bariatric surgery, and nutritional and pharmacotherapy of NASH are discussed in this review. Overall, aggressive management of metabolic syndrome after LT via medical and surgical modalities and a minimalist approach to immunosuppression is advised.

Proceedings of the 2017 ASPEN Research Workshop-Gastric Bypass: Role of the Gut

The goal of the National Institutes of Health-funded American Society for Parenteral and Enteral Nutrition 2017 research workshop (RW) "Gastric Bypass: Role of the Gut" was to focus on the exciting research evaluating gut-derived signals in modulating outcomes after bariatric surgery. Although gastric bypass surgery has undoubted positive effects, the mechanistic basis of improved outcomes cannot be solely explained by caloric restriction. Emerging data suggest that bile acid metabolic pathways, luminal contents, energy balance, gut mucosal integrity, as well as the gut microbiota are significantly modulated after bariatric surgery and may be responsible for the variable outcomes, each of which was rigorously evaluated. The RW served as a timely and novel academic meeting that brought together clinicians and researchers across the scientific spectrum, fostering a unique venue for interdisciplinary collaboration among investigators. It promoted engaging discussion and evolution of new research hypotheses and ideas, driving the development of novel ameliorative, therapeutic, and nonsurgical interventions targeting obesity and its comorbidities. Importantly, a critical evaluation of the current knowledge regarding gut-modulated signaling after bariatric surgery, potential pitfalls, and lacunae were thoroughly addressed.

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

BACKGROUND

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSION

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

Impact of Weight Regain on the Evolution of Non-alcoholic Fatty Liver Disease After Roux-en-Y Gastric Bypass: a 3-Year Follow-up

BACKGROUND

The influence of post-surgical weight regain on the course of non-alcoholic fatty liver disease (NAFLD) is unclear.

OBJECTIVE

To evaluate the influence of weight regain on the NAFLD assessed by means of a non-invasive score after Roux-en-gastric bypass (RYGB) over a 3-year period.

METHODS

This is a prospective observational cohort study which evaluated individuals who underwent RYGB. Comparisons were made between the periods immediately before surgery and 12, 24, and 36 months following surgery. Liver disease was estimated by means of the NAFLD fibrosis score. Individuals were classified into three categories according to weight regain status: (1) no weight regain, (2) expected weight regain (regain less or equal than 20% of the maximal weight lost), (3) obesity recidivism (regain above 20% of the maximal weight lost).

RESULTS

Of 90 patients analyzed after 3 years of surgery, 35.6% presented obesity recidivism and 28.8% of the expected regain; 35.6% presented no regain. There was no difference in baseline fibrosis score between groups; at 3 years, the score observed in the relapse group was significantly higher than that observed in the other two groups (p = 0.015). The percent variation of the fibrosis score was significantly higher in the recidivism group (+ 11.8 ± 77.2%) than in the expected regain (- 45.6 ± 64.5%) and no regain (- 37.8 ± 63.2%) groups (p = 0.013).

CONCLUSION

Long-term significant post-RYGB weight regain is associated with a significantly attenuated improvement of NAFLD evaluated by means of liver fibrosis score.

Effects of Two Preoperatory Weight Loss Diets on Hepatic Volume, Metabolic Parameters, and Surgical Complications in Morbid Obese Bariatric Surgery Candidates: a Randomized Clinical Trial

OBJECTIVE

To assess which type of preoperative dietary strategy is most effective in reducing liver volume and assessing its influence on different biochemical parameters and on surgical complications in individuals undergoing bariatric surgery.

METHODS

Parallel randomized trial comparing the effect of a very low calorie diet (VLCD) and a low calorie diet (LCD) for a period of 21 days before surgery on hepatic volume, anthropometric and biochemical parameters. Compliance and tolerance to the diets, surgical complications, and hospital stay were also determined.

RESULTS

Eighty-six morbid obese participants undergoing bariatric surgery were randomized. The hepatic volume was significantly reduced in both intervention groups, but no differences in changes between groups were detected. The reduction in the hepatic volume was higher in those patients with a baseline hepatic volume > 3 L compared to those with < 3 L (adjusted P value < 0.001). The percentages of total weight lost were 5.8 and 4.2% (adjusted P value = 0.004) for participants on the VLCD and LCD, respectively. There were no differences between groups for any of the biochemical parameters analyzed, nor in the number of surgical complications nor the length of hospital stay. Adherence to the diet was good; nevertheless, participants in the VLCD intervention showed worse tolerance.

CONCLUSIONS

In subjects with morbid obesity undergoing bariatric surgery, compared to a LCD, a preoperative 21-day intervention with VLCD is more effective in terms of reducing total body weight but not in terms of reducing the liver volume. Both types of preoperative diets have similar effects on clinical biochemical parameters, rate of surgical complications, and hospital length stay.

Changes in Bone Mineral Density Following Weight Loss Induced by One-Anastomosis Gastric Bypass in Patients with Vitamin D Supplementation

BACKGROUND

Little is known about changes in bone mineral density (BMD) following weight loss after one-anastomosis gastric bypass (OAGB) and the role of serum vitamin D and its supplementation on bone metabolism. We evaluated BMD after OAGB as a function of vitamin D supplementation with respect to a minimum threshold of 25-hydroxy-vitamin-D [25(OH)D] concentration, which could prevent or decelerate an eventual bone loss.

METHODS

Fifty bariatric patients who participated in the randomized controlled trial were included in this analysis. BMD and anthropometric measurements by DXA and laboratory parameters were assessed before (T0), at 6 (T6), and 12 months (T12) after surgery.

RESULTS

OAGB resulted in a 36% total body weight loss with a decrease in body fat and an increase in lean body mass. A significant decrease in BMD was seen in lumbar spine by 7%, left hip 13%, and total body 1%, but not in forearm. Bone turnover markers increased significantly but with normal parathyroid hormone concentrations. Weight loss was not associated with changes in BMD. A serum 25(OH)D concentration > 50 nmol/l at T6 and T12 (adequate-vitamin-D-group; AVD) showed a significant lower bone loss, compared to the inadequate-vitamin-D-group (IVD; < 50 nmol/l). Lower bone loss in the left hip showed a strong correlation with higher 25(OH)D concentrations (r = 0.635, p = 0.003).

CONCLUSION

These findings support a dose effect of vitamin D supplementation on bone health and suggest that 25(OH)D concentrations need to be above 50 nmol/l at least during the first postoperative year to decelerate bone loss in patients undergoing OAGB.

CLINICAL TRIAL REGISTRY NUMBER AND WEBSITE

Clinicaltrials.gov (NCT02092376) at https://clinicaltrials.gov /. EudraCT (2013-003546-16) at https://eudract.ema.europa.eu /.

Transient elastography: should XL probe be used in all overweight patients?

Background: Obesity is one of the main factors of transient elastography (TE) failure, considering body mass index (BMI) ≥28 kg/m² as a limiting factor. The XL probe was designed to overcome this limitation. Aim: To compare the feasibility of the M and XL probes in patients with BMI ≥ 28 kg/m², to evaluate differences in mean values of controlled attenuation parameter (CAP) and liver stiffness measurement (LSM) between the two probes and find predictive factors of TE failure. Material and methods: Prospective study, including all patients with BMI ≥ 28 kg/m² consecutively admitted for TE. Results: Included 161 patients. Measurements with M probe were reliable in 69.6% of the patients, with 68.2% of valid measurements in obese population and 58.9% in patients with skin-capsule distance (SCD) >25 mm. In 40 patients (81.6%) with an invalid M probe measurement, a reliable result was obtained with XL probe. We found that SCD >25 mm was the only predictor of M probe failure (OR: 4.9, CI: 1.64-14.63, p = .004). In those patients in which TE was possible with both probes (n = 112), mean CAP was 304 ± 49 dB/m² with M probe and 301 ± 50 dB/m² with XL probe (p = .59). Regarding liver stiffness, a mean value of 7.58 ± 3.47 kpas was obtained with the M probe and 6.21 ± 3.44 kpas with the XL probe (p < .001). Conclusion: There is a reliable applicability of the M probe in a high number (68.2%) of patients with a BMI ≥30 kg/m². A SCD >25 mm was the only predictive factor of M probe failure. Mean values of LSM with XL probe were lower than those obtained with M probe.