Cost-effectiveness Analysis of Bariatric Surgery for Patients With Nonalcoholic Steatohepatitis Cirrhosis

Asian Pacific Association for the Study of the Liver clinical practice guidelines on liver transplantation

Liver transplantation is a highly complex and challenging field of clinical practice. Although it was originally developed in western countries, it has been further advanced in Asian countries through the use of living donor liver transplantation. This method of transplantation is the only available option in many countries in the Asia-Pacific region due to the lack of deceased organ donation. As a result of this clinical situation, there is a growing need for guidelines that are specific to the Asia-Pacific region. These guidelines provide comprehensive recommendations for evidence-based management throughout the entire process of liver transplantation, covering both deceased and living donor liver transplantation. In addition, the development of these guidelines has been a collaborative effort between medical professionals from various countries in the region. This has allowed for the inclusion of diverse perspectives and experiences, leading to a more comprehensive and effective set of guidelines.

Semaglutide vs Endoscopic Sleeve Gastroplasty for Weight Loss

Importance

Obesity is a disease with a large socioeconomic burden. Endoscopic sleeve gastroplasty (ESG) is a minimally invasive endoscopic bariatric procedure with wide global adoption. More recently, new weight-loss medications, such as glucagon-like peptide-1 receptor agonists (eg, semaglutide), have attracted increased attention due to their efficacy. However, their cost-effectiveness over an extended period compared with ESG is a critical gap that needs to be better explored for informed health care decision-making.

Objective

To assess the cost-effectiveness of semaglutide compared with ESG over 5 years for individuals with class II obesity.

Design, Setting, and Participants

This economic evaluation study, conducted from September 1, 2022, to May 31, 2023, used a Markov cohort model to compare ESG and semaglutide, with a no-treatment baseline strategy. The study comprised adult patients in the US health care system with class II obesity (body mass index [BMI] of 35-39.9). The base case was a 45-year-old patient with class II obesity (BMI of 37). Patients undergoing ESG were subjected to risks of perioperative mortality and adverse events with resultant costs and decrement in quality of life.

Interventions

Strategies included treatment with semaglutide and ESG.

Main Outcomes and Measures

Costs (2022 US dollars), quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratio (ICER) with a willingness-to-pay threshold of $100 000/QALY. A 5-year time horizon with a cycle length of 1 month with a 3% discount rate was used. Probabilities, costs, and quality-of-life estimates of the model were derived from published literature. One-way, 2-way, and probabilistic sensitivity analyses were also performed.

Results

The model found that ESG was more cost-effective than semaglutide over a 5-year time horizon, with an ICER of -$595 532/QALY. Endoscopic sleeve gastroplasty added 0.06 QALYs and reduced total cost by $33 583 relative to semaglutide. The results remained robust on 1-way and probabilistic sensitivity analyses. Endoscopic sleeve gastroplasty sustained greater weight loss over 5 years vs semaglutide (BMI of 31.7 vs 33.0). To achieve nondominance, the annual price of semaglutide, currently $13 618, would need to be $3591.

Conclusions and Relevance

This study suggests that ESG is cost saving compared with semaglutide in the treatment of class II obesity. On price threshold analyses, a 3-fold decrease in the price of semaglutide is needed to achieve nondominance.

Cardiovascular outcomes post bariatric surgery in patients with metabolic dysfunction-associated steatotic liver disease - A systematic review and meta-analysis

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease (NAFLD), is linked with an increased risk of adverse cardiovascular events. Studies have suggested an association between the reduction of incident cardiovascular events in patients with MASLD after bariatric surgery. This systematic review and meta-analysis were performed to assess the influence of bariatric surgery on cardiovascular outcomes in patients with diagnosed MASLD by identifying all available cohort studies and pooling their data.

METHODS

PubMed and Google Scholar databases were searched till July 2023 for published studies that assessed the effect of bariatric surgery on cardiovascular outcomes in MASLD patients. Using a random effects model, hazard ratios (HRs) with 95 % confidence intervals (CIs) were pooled.

RESULTS

The systematic review identified three cohort studies. The analysis of 240,516 MASLD patients found a significantly reduced incidence of cardiovascular events. (HR 0.51; 95 % CI 0.48 to 0.54, P value <0.00001).

CONCLUSION

Bariatric surgery in MASLD patients significantly reduced the incidence of cardiovascular events, suggesting that bariatric surgery is an effective therapeutic tool among MASLD patients compared to non-surgical interventions.

Healthcare and socioeconomic costs of NAFLD: A global framework to navigate the uncertainties

Left unaddressed, non-alcoholic fatty liver disease (NAFLD) will continue to have substantial health, economic and social implications. To address the challenge, a paradigm shift is needed in the way NAFLD is conceptualised. Concerted, collaborative action across medical specialities, industry sectors and governments will be vital in tackling this public health threat. To drive this change, in this review, we present data on the current global healthcare and socioeconomic costs of NAFLD and highlight priority actions. The estimated healthcare costs of patients with NAFLD are nearly twice as high as their age-matched counterparts without the disease and are highest in those with advanced fibrosis and end-stage liver disease. NAFLD is accountable for the highest increase in DALYs (disability-adjusted life years) among all liver diseases globally. NAFLD and non-alcoholic steatohepatitis (NASH)-specific drug therapies are not yet available and there is considerable uncertainty regarding cost, optimal length of treatment, and their impact on liver-related outcomes and mortality. Among the currently available bariatric procedures, sleeve gastrectomy is reported to be the most cost-effective for NASH resolution. Gastric bypass remains very expensive, while data on bariatric endoscopy are limited. Lastly, we propose a global NAFLD/NASH investment framework to guide the development of achievable yet ambitious country-specific targets and strategic actions to optimise resource allocation and reduce the prevalence of NAFLD and NASH. Its focus on high-level inputs will be critical to enabling a political and financial environment that supports clinical-level implementation of NAFLD prevention, treatment and care efforts, across all settings.

Disease Progression Modeling for Economic Evaluation in Nonalcoholic Fatty Liver Disease-A Systematic Review

BACKGROUND & AIMS

Globally, 25% of people have nonalcoholic fatty liver disease (NAFLD), and, currently, there are no approved pharmacologic treatments for NAFLD. With a slow disease progression, long-term impact of pharmacologic treatments can be assessed only by complementing emerging clinical trial evidence with data from other sources in disease progression modeling. Although this modeling is crucial for economic evaluation studies assessing the clinical and economic consequences of new treatments, the approach to modeling the natural history of NAFLD differs in contemporary research. This systematic literature review investigated modeling of the natural history of NAFLD.

METHODS

A systematic literature review was conducted searching PubMed, Scopus, Cochrane, and the National Health Service Economic Evaluation Database to identify articles focusing on modeling of the natural history of NAFLD. Model structure and transition probabilities were extracted from included studies.

RESULTS

Of the 28 articles identified, differences were seen in model structure and data input. Clear definitions of nonalcoholic steatohepatitis and NAFLD often were lacking; differences in the granularity of modeling fibrosis progression, the approach to disease regression, and modeling of advanced liver disease varied across studies. Observed transition probabilities for F0 to F1, F1 to F2, F2 to F3, and F3 to compensated cirrhosis varied between 0.059 to 0.095, 0.023 to 0.140, 0.018 to 0.070, and 0.040 to 0.118, respectively.

CONCLUSIONS

The difference in disease progression modeling for seemingly similar models warrants further inquiry regarding how to model the natural course of NAFLD. Such differences may have a large impact when assessing the value of emerging pharmacologic treatments.

Liver fibrosis and MAFLD: the exploration of multi-drug combination therapy strategies

In recent years, the prevalence of metabolic-associated fatty liver disease (MAFLD) has reached pandemic proportions as a leading cause of liver fibrosis worldwide. However, the stage of liver fibrosis is associated with an increased risk of severe liver-related and cardiovascular events and is the strongest predictor of mortality in MAFLD patients. More and more people believe that MAFLD is a multifactorial disease with multiple pathways are involved in promoting the progression of liver fibrosis. Numerous drug targets and drugs have been explored for various anti-fibrosis pathways. The treatment of single medicines is brutal to obtain satisfactory results, so the strategies of multi-drug combination therapies have attracted increasing attention. In this review, we discuss the mechanism of MAFLD-related liver fibrosis and its regression, summarize the current intervention and treatment methods for this disease, and focus on the analysis of drug combination strategies for MAFLD and its subsequent liver fibrosis in recent years to explore safer and more effective multi-drug combination therapy strategies.

Cost-effectiveness of Staple Line Reinforcement in Laparoscopic Sleeve Gastrectomy

OBJECTIVE

To perform a cost-effectiveness analysis of staple-line reinforcement in laparoscopic sleeve gastrectomy.

SUMMARY OF BACKGROUND DATA

Exponential increases in surgical costs have underscored the critical need for evidence-based methods to determine the relative value of surgical devices. One such device is staple-line reinforcement, thought to decrease bleeding rates in laparoscopic sleeve gastrectomy.

METHODS

Two intervention arms were modeled, staple-line reinforcement and standard nonreinforced stapling. Bleed and leak rates and 30-day treatment costs were obtained from national and state registries. Quality-adjusted life-year (QALY) values were drawn from previous literature. Device prices were drawn from institutional data. A final incremental cost-effectiveness ratio was calculated, and one-way and probabilistic sensitivity analyses were performed.

RESULTS

A total of 346,530 patient records from 2012 to 2018 were included. Complication rates for the reinforced and standard cohorts were 0.05% for major bleed in both cohorts ( P = 0.8841); 0.45% compared with 0.59% for minor bleed ( P < 0.0001); and 0.24% compared with 0.26% for leak ( P = 0.4812). Median cost for a major bleed was $5552 ($3287, $16,817) and $2406 ($1861, $3484) for a minor bleed. Median leak cost was $9897 ($4589, $21,619) and median cost for patients who did not experience a bleed, leak, or other serious complication was $1908 ($1712, $2739). Mean incremental cost of reinforced stapling compared with standard was $819.60/surgery. Net QALY gain with reinforced stapling compared with standard was 0.00002. The resultant incremental cost-effectiveness ratio was $40,553,000/QALY. One-way and probabilistic sensitivity analyses failed to produce a value below $150,000/QALY.

CONCLUSIONS

Compared with standard stapling, reinforced stapling reduces minor postoperative bleeding but not major bleeding or leaks and is not cost-effective if routinely used in laparoscopic sleeve gastrectomy.

Endoscopic Balloon Dilation Is Cost-Effective for Crohn's Disease Strictures

BACKGROUND

Endoscopic balloon dilation (EBD) has emerged as an alternative intervention to manage Crohn's disease (CD) strictures. We determined the cost-effectiveness of EBD versus resection surgery for patients with short (< 4-5 cm) primary or secondary/anastomotic small or large bowel strictures.

METHODS

A microsimulation state-transition model analyzed the benefits and risks of EBD and resection surgery for patients with primary or anastomotic CD strictures. Our primary outcome was quality-adjusted life years (QALYs) over ten years, and strategies were compared using a willingness to pay of $100,000/QALY from a societal perspective. Costs (2021 $US) and incremental cost-effectiveness ratios (ICER) were calculated. Deterministic 1-way and probabilistic analyses assessed model uncertainty.

RESULTS

The EBD strategy cost $19,822 and resulted in 6.18 QALYs while the surgery strategy cost $41,358 and resulted in 6.37 QALYs. Surgery had an ICER of $113,332 per QALY, making EBD a cost-effective strategy. The median number of EBDs was 5 in the EBD strategy and 0 in the surgery strategy. The median number of surgeries was 2 in the surgery strategy and 1 in the EBD strategy. Of individuals who initially received EBD, 50.4% underwent subsequent surgery. One-way sensitivity analyses showed that the probabilities of requiring repeated interventions, surgery mortality (< 0.7%), and quality of life after interventions were the most influential model parameters. Probabilistic sensitivity analyses favored EBD in 50.9% of iterations.

CONCLUSIONS

EBD is a cost-effective strategy for managing CD strictures. Differences in patient risk and quality of life after intervention impact cost-effectiveness. Intervention decisions should consider cost-effectiveness, patient risks, and quality of life.

Association of Bariatric Surgery With Cardiovascular Outcomes in Adults With Severe Obesity and Nonalcoholic Fatty Liver Disease

IMPORTANCE

There are no approved treatments for nonalcoholic fatty liver disease (NAFLD) despite its association with obesity and increased risk of cardiovascular disease (CVD).

OBJECTIVE

To examine the association between bariatric surgery and CVD risk in individuals with severe obesity and NAFLD.

DESIGN, SETTING, AND PARTICIPANTS

This large, population-based retrospective cohort study obtained data from the MarketScan Commercial Claims and Encounters database from January 1, 2007, to December 31, 2017. Participants included insured adults aged 18 to 64 years with NAFLD and severe obesity (body mass index ≥40) without a history of bariatric surgery or CVD before NAFLD diagnosis. Baseline characteristics were balanced between individuals who underwent surgery (surgical group) and those who did not (nonsurgical group) using inverse probability of treatment weighting. Data were analyzed from March 2020 to April 2021.

EXPOSURES

Bariatric surgery (Roux-en-Y gastric bypass, sleeve gastrectomy, and other bariatric procedures) vs nonsurgical care.

MAIN OUTCOMES AND MEASURES

The main outcome was the incidence of cardiovascular events (primary or secondary composite CVD outcomes). The primary composite outcome included myocardial infarction, heart failure, or ischemic stroke, and the secondary composite outcome included secondary ischemic heart events, transient ischemic attack, secondary cerebrovascular events, arterial embolism and thrombosis, or atherosclerosis. Cox proportional hazards regression models with inverse probability treatment weighting were used to examine the associations between bariatric surgery, modeled as time varying, and all outcomes.

RESULTS

The study included 86 964 adults (mean [SD] age, 44.3 [10.9] years; 59 773 women [68.7%]). Of these individuals, 30 300 (34.8%) underwent bariatric surgery and 56 664 (65.2%) received nonsurgical care. All baseline covariates were balanced after applying inverse probability treatment weighting. In the surgical group, 1568 individuals experienced incident cardiovascular events compared with 7215 individuals in the nonsurgical group (incidence rate difference, 4.8 [95% CI, 4.5-5.0] per 100 person-years). At the end of the study, bariatric surgery was associated with a 49% lower risk of CVD (adjusted hazard ratio [aHR], 0.51; 95% CI, 0.48-0.54) compared with nonsurgical care. The risk of primary composite CVD outcomes was reduced by 47% (aHR, 0.53 [95% CI, 0.48-0.59), and the risk of secondary composite CVD outcomes decreased by 50% (aHR, 0.50; 95% CI, 0.46-0.53) in individuals with vs without surgery.

CONCLUSIONS AND RELEVANCE

Results of this study suggest that, compared with nonsurgical care, bariatric surgery was associated with significant reduction in CVD risk in individuals with severe obesity and NAFLD.

Reverse Total Shoulder Arthroplasty Is the Most Cost-effective Treatment Strategy for Proximal Humerus Fractures in Older Adults: A Cost-utility Analysis

BACKGROUND

Proximal humerus fractures are the second-most common fragility fracture in older adults. Although reverse total shoulder arthroplasty (RTSA) is a promising treatment strategy for proximal humerus fractures with favorable clinical and quality of life outcomes, it is associated with much higher, and possibly prohibitive, upfront costs relative to nonoperative treatment and other surgical alternatives.

QUESTIONS/PURPOSES

(1) What is the cost-effectiveness of open reduction internal fixation (ORIF), hemiarthroplasty, and RTSA compared with the nonoperative treatment of complex proximal humerus fractures in adults older than 65 years from the perspective of a single-payer Canadian healthcare system? (2) Which factors, if any, affect the cost-effectiveness of ORIF, hemiarthroplasty, and RTSA compared with nonoperative treatment of proximal humerus fractures including quality of life outcomes, cost, and complication rates after each treatment?

METHODS

This cost-utility analysis compared RTSA, hemiarthroplasty, and ORIF with the nonoperative management of complex proximal humerus fractures in adults older than 65 years over a lifetime time horizon from the perspective of a single-payer healthcare system. Short-term and intermediate-term complications in the 2-year postoperative period were modeled using a decision tree, with long-term outcomes estimated through a Markov model. The model was initiated with a cohort of 75-year-old patients who had a diagnosis of a comminuted (three- or four-part) proximal humerus fractures; 90% of the patients were women. The mean age and gender composition of the model's cohort was based on a systematic review conducted as part of this analysis. Patients were managed nonoperatively or surgically with either ORIF, hemiarthroplasty, or RTSA. The three initial surgical treatment options of ORIF, hemiarthroplasty, and RTSA resulted in uncomplicated healing or the development of a complication that would result in a subsequent surgical intervention. The model reflects the complications that result in repeat surgery and that are assumed to have the greatest impact on clinical outcomes and costs. Transition probabilities and health utilities were derived from published sources, with costs (2020 CAD) sourced from regional costing databases. The primary outcome was the incremental cost-utility ratio, which was calculated using expected quality-adjusted life years (QALYs) gained and costs. Sensitivity analyses were conducted to explore the impact of changing key model parameters.

RESULTS

Based on both pairwise and sequential analysis, RTSA was found to be the most cost-effective strategy for managing complex proximal humerus fractures in adults older than 65 years. Compared with nonoperative management, the pairwise incremental cost-utility ratios of hemiarthroplasty and RTSA were CAD 25,759/QALY and CAD 7476/QALY, respectively. ORIF was dominated by nonoperative management, meaning that it was both more costly and less effective. Sequential analysis, wherein interventions are compared from least to most expensive in a pairwise manner, demonstrated ORIF to be dominated by hemiarthroplasty, and hemiarthroplasty to be extendedly dominated by RTSA. Further, at a willingness-to-pay threshold of CAD 50,000/QALY, RTSA had 66% probability of being the most cost-effective treatment option. The results were sensitive to changes in the parameters for the probability of revision RTSA after RTSA, the treatment cost of RTSA, and the health utilities associated with the well state for all treatment options except ORIF, although none of these changes were found to be clinically realistic based on the existing evidence.

CONCLUSION

Based on this economic analysis, RTSA is the preferred treatment strategy for complex proximal humerus fractures in adults older than 65 years, despite high upfront costs. Based on the evidence to date, it is unlikely that the parameters this model was sensitive to would change to the degree necessary to alter the model's outcome. A major strength of this model is that it reflects the most recent randomized controlled trials evaluating the management of this condition. Therefore, clinicians should feel confident recommending RTSA for the management of proximal humerus fractures in adults older than 65 years, and they are encouraged to advocate for this intervention as being a cost-effective practice, especially in publicly funded healthcare systems wherein resource stewardship is a core principle. Future high-quality trials should continue to collect both clinical and quality of life outcomes using validated tools such as the EuroQOL-5D to reduce parameter uncertainty and support decision makers in understanding relevant interventions' value for money.

LEVEL OF EVIDENCE

Level III, economic and decision analysis.

Non-alcoholic fatty liver disease: Is surgery the best current option and can novel endoscopy play a role in the future?

Over the last decade, non-alcoholic fatty liver disease (NAFLD) has overtaken alcohol as the leading cause of cirrhosis in the Western world. There remains to be a licensed pharmacological treatment for NAFLD. Weight loss is advised for all patients with NAFLD. Many patients however, struggle to lose the recommended weight with lifestyle modification alone. Many drugs have either failed to show significant improvement of steatosis or are poorly tolerated. Bariatric surgery has been shown to reduce liver steatosis and regress liver fibrosis. The pathophysiology is not fully understood, however recent evidence has pointed towards changes in the gut microbiome following surgery. Novel endoscopic treatment options provide a minimally invasive alternative for weight loss. Randomised controlled trials are now required for further clarification.

The Impact of Bariatric-Surgery-Induced Weight Loss on Patients Undergoing Liver Transplant: A Focus on Metabolism, Pathophysiological Changes, and Outcome in Obese Patients Suffering NAFLD-Related Cirrhosis

Because of their condition, patients with morbid obesity develop several histopathological changes in the liver, such as non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), cirrhosis, and end-stage liver disease (ESLD). Hence, a liver transplant (LT) becomes an opportune solution for them. Due to many challenges during the perioperative and postoperative periods, these patients are recommended to lose weight before the surgery. There are many proposals to achieve this goal, such as intragastric balloons and many different bariatric surgery (BS) procedures in combination with a preparation diet (very-low-calorie diet, ketogenic diet, etc.). All the interventions focus on losing weight and keeping the continuity and functionality of the digestive tract to avoid postoperative complications. Thus, this review analyzes recent publications regarding the metabolic and pathophysiological impacts of BS in LT patients suffering from NAFLD-related cirrhosis, the effect of weight loss on postoperative complications, and exposes the cost-effectiveness of performing BS before, after, and at liver transplantation. Finally, the authors recommend BS before the LT since there are many positive effects and better outcomes for patients who lose weight before the procedure. Nevertheless, further multicentric studies are needed to determine the generalizability of these recommendations due to their impact on public health.

European guideline on obesity care in patients with gastrointestinal and liver diseases - Joint European Society for Clinical Nutrition and Metabolism / United European Gastroenterology guideline

BACKGROUND

Patients with chronic gastrointestinal (GI) disease such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), celiac disease, gastroesophageal reflux disease (GERD), pancreatitis, and chronic liver disease (CLD) often suffer from obesity because of coincidence (IBD, IBS, celiac disease) or related pathophysiology (GERD, pancreatitis and CLD). It is unclear if such patients need a particular diagnostic and treatment that differs from the needs of lean GI patients. The present guideline addresses this question according to current knowledge and evidence.

OBJECTIVE

The objective of the guideline is to give advice to all professionals working in the field of gastroenterology care including physicians, surgeons, dietitians and others how to handle patients with GI disease and obesity.

METHODS

The present guideline was developed according to the standard operating procedure for European Society for Clinical Nutrition and Metabolism guidelines, following the Scottish Intercollegiate Guidelines Network grading system (A, B, 0, and good practice point [GPP]). The procedure included an online voting (Delphi) and a final consensus conference.

RESULTS

In 100 recommendations (3x A, 33x B, 24x 0, 40x GPP, all with a consensus grade of 90% or more) care of GI patients with obesity - including sarcopenic obesity - is addressed in a multidisciplinary way. A particular emphasis is on CLD, especially fatty liver disease, since such diseases are closely related to obesity, whereas liver cirrhosis is rather associated with sarcopenic obesity. A special chapter is dedicated to obesity care in patients undergoing bariatric surgery. The guideline focuses on adults, not on children, for whom data are scarce. Whether some of the recommendations apply to children must be left to the judgment of the experienced pediatrician.

CONCLUSION

The present guideline offers for the first time evidence-based advice how to care for patients with chronic GI diseases and concomitant obesity, an increasingly frequent constellation in clinical practice.

European guideline on obesity care in patients with gastrointestinal and liver diseases - Joint ESPEN/UEG guideline

BACKGROUND

Patients with chronic gastrointestinal (GI) disease such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), celiac disease, gastroesophageal reflux disease (GERD), pancreatitis, and chronic liver disease (CLD) often suffer from obesity because of coincidence (IBD, IBS, celiac disease) or related pathophysiology (GERD, pancreatitis and CLD). It is unclear if such patients need a particular diagnostic and treatment that differs from the needs of lean GI patients. The present guideline addresses this question according to current knowledge and evidence.

OBJECTIVE

The objective of the guideline is to give advice to all professionals working in the field of gastroenterology care including physicians, surgeons, dietitians and others how to handle patients with GI disease and obesity.

METHODS

The present guideline was developed according to the standard operating procedure for ESPEN guidelines, following the Scottish Intercollegiate Guidelines Network (SIGN) grading system (A, B, 0, and good practice point (GPP)). The procedure included an online voting (Delphi) and a final consensus conference.

RESULTS

In 100 recommendations (3x A, 33x B, 24x 0, 40x GPP, all with a consensus grade of 90% or more) care of GI patients with obesity - including sarcopenic obesity - is addressed in a multidisciplinary way. A particular emphasis is on CLD, especially fatty liver disease, since such diseases are closely related to obesity, whereas liver cirrhosis is rather associated with sarcopenic obesity. A special chapter is dedicated to obesity care in patients undergoing bariatric surgery. The guideline focuses on adults, not on children, for whom data are scarce. Whether some of the recommendations apply to children must be left to the judgment of the experienced pediatrician.

CONCLUSION

The present guideline offers for the first time evidence-based advice how to care for patients with chronic GI diseases and concomitant obesity, an increasingly frequent constellation in clinical practice.

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.

Long-term Impact of Laparoscopic Sleeve Gastrectomy on Drug Costs of Japanese Patients with Obesity and Type 2 Diabetes Mellitus

PURPOSE

Laparoscopic sleeve gastrectomy (LSG) is the most common type of bariatric surgery in Japan, and it is the only such procedure covered by national health insurance. The long-term cost of bariatric surgery in Japan has not yet been analyzed. We aimed to evaluate the long-term impact of LSG on the drug treatment costs of patients with type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

We retrospectively analyzed data from 230 patients who had undergone LSG at our institution for their obesity and T2DM between 2007 and 2018. The clinicopathological data included age, sex, body mass index (BMI), as well as preoperative and postoperative medications for T2DM, hypertension, and dyslipidemia. We then calculated the drug treatment costs for T2DM, hypertension, and dyslipidemia before and after LSG; and we evaluated the remission rates of these obesity-related diseases.

RESULTS

The median preoperative body weight and BMI of the 230 patients who underwent LSG were 115 kg and 40.6 kg/m², respectively. Preoperative drug treatment costs per month per patient for T2DM, hypertension, and dyslipidemia were ¥3795 (¥0-40285), ¥3269 (¥0-14577), and ¥1428 (¥0-19464). Post-operation, the median drug treatment costs for all these diseases became nil. The remission rates of T2DM, hypertension, and dyslipidemia 5 years after LSG were 82.8%, 50%, and 43.8%, respectively. In Japan, the cost of an LSG operation corresponds to 4.75 years of median drug costs to treat T2DM and hypertension.

CONCLUSION

In the long term, LSG in Japan is effective both physically and cost-wise for patients with obesity and T2DM.

Therapeutic developments in metabolic dysfunction-associated fatty liver disease

Metabolic dysfunction-associated fatty liver disease (MAFLD) has become one of the most prevalent chronic liver diseases worldwide, bringing risk of multiorgan disfunctions including cardiovascular events, complications of cirrhosis, and even malignance. In terms of health burden management, screening patients with high risk of MAFLD and providing individual comprehensive treatment is critical. Although there are numerous agents entering clinical trials for MAFLD treatment every year, there is still no effective approved drug. The nomenclature of MAFLD highlighted the concomitant metabolic disorders and obesity. MAFLD patients with type 2 diabetes had higher risk of developing liver cirrhosis and cancer, and would benefit from anti-hyperglycemic agents; overweight and obese patients may benefit more from weight loss therapies; for patients with metabolic syndrome, individual comprehensive management is needed to reduce the risk of adverse outcomes. In this review, we introduced the current status and advances of the treatment of MAFLD based on weight loss, improving insulin resistance, and management of cardiometabolic disorders, in order to provide individualized therapy approaches for patients with MAFLD.

Bariatric Surgery in NAFLD

Currently, there are no approved medications to treat patients with nonalcoholic steatohepatitis (NASH) with fibrosis or cirrhosis. Although the management goal in these patients is weight reduction by 7-10% with lifestyle modifications, only less than 10% of patients achieve this target at 1-year, and fewer maintain the weight loss at 5 years. Bariatric surgery is an option that may be considered in those who fail to lose weight by lifestyle changes. Bariatric surgery has been shown to improve liver histology including fibrosis secondary to NASH, in addition to other benefits including an improvement or resolution of type 2 diabetes mellitus, dyslipidemia, and hypertension, and a reduction of cardiovascular morbidity or mortality. There are no guidelines of bariatric surgery indications for the management of NASH. The purpose of this review is to critically appraise the current knowledge of the role of bariatric surgery and the potential mechanisms for its perceived benefits in the management of patients with NASH-related liver disease.

Comparison of Liver Recovery After Sleeve Gastrectomy and Roux-en-Y-Gastric Bypass

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a common condition in patients with obesity. Bariatric surgery has often been proposed as a viable treatment option, but the ideal surgical procedure remains unclear. Inconsistently, reports on postoperative deterioration of liver function put further doubt on which technique to apply. Aim of this study was to assess the impact of Roux-en-Y-gastric bypass (RYGB) and sleeve gastrectomy (SG) on the postoperative recovery of liver function.

METHODS

A total of 175 patients with obesity that underwent bariatric surgery in our institution were included in this prospective cohort study. BMI, laboratory values, and liver function capacity (using LiMAx) were assessed preoperatively and at 6 and 12 months postoperatively. Generalized linear model (GLM) was performed to determine variables influencing liver function capacity after the operation.

RESULTS

Prior to operations, 64% of patients presented with a diminished liver function capacity, as measured by LiMAx test. Liver function capacity significantly recovered after 12 months in the SG group (300 μg/kg/h preop vs. 367 μg/kg/h postop) but not in the RYGB group (306 μg/kg/h preop vs. 349 μg/kg/h). Preoperative factors impeding liver function recovery included type 2 diabetes mellitus (T2DM), weight, male sex, AST/thrombocyte ratio (APRI), and gamma-glutamyltransferase (GGT).

CONCLUSION

Bariatric surgery, especially sleeve gastrectomy, leads to an improvement of liver function. However, in some patients with T2DM, higher preoperative weight and male sex postoperative deterioration of liver function capacity may occur.

Nationwide cost-effectiveness analysis of surgical stabilization of rib fractures by flail chest status and age groups

BACKGROUND

Surgical stabilization of rib fracture (SSRF) is increasingly used to manage patients with rib fractures. Benefits of performing SSRF appear variable, and the procedure is costly, necessitating cost-effectiveness analysis for distinct subgroups. We aimed to assess the cost-effectiveness of SSRF versus nonoperative management among patients with rib fractures younger than 65 years versus 65 years or older, with versus without flail chest. We hypothesized that, compared with nonoperative management, SSRF is cost-effective only for patients with flail chest.

METHODS

This economic evaluation used a decision-analytic Markov model with a lifetime time horizon incorporating US population-representative inputs to simulate benefits and risks of SSRF compared with nonoperative management. We report quality-adjusted life years (QALYs), costs, and incremental cost-effectiveness ratios. Deterministic and probabilistic sensitivity analyses accounted for most plausible clinical scenarios.

RESULTS

Compared with nonoperative management, SSRF was cost-effective for patients with flail chest at willingness-to-pay threshold of US $150,000/QALY gained. Surgical stabilization of rib fracture costs US $25,338 and US $123,377/QALY gained for those with flail chest younger than 65 years and 65 years or older, respectively. Surgical stabilization of rib fracture was not cost-effective for patients without flail chest, costing US $172,704 and US $243,758/QALY gained for those younger than 65 years and 65 years or older, respectively. One-way sensitivity analyses showed that, under most plausible scenarios, SSRF remained cost-effective for subgroups with flail chest, and nonoperative management remained cost-effective for patients older than 65 years without flail chest. Probability that SSRF is cost-effective ranged from 98% among patients younger than 65 years with flail chest to 35% among patients 65 years or older without flail chest.

CONCLUSIONS

Surgical stabilization of rib fracture is cost-effective for patients with flail chest. Surgical stabilization of rib fracture may be cost-effective in some patients without flail chest, but delineating these patients requires further study.

LEVEL OF EVIDENCE

Economic/decision, level II.

Obesity Management of Liver Transplant Waitlist Candidates and Recipients

Obesity is increasing in prevalence in liver transplant candidates and recipients. The rise in liver transplantation for nonalcoholic steatohepatitis reflects this increase. Management of obesity in liver transplant candidates can be challenging due to the presence of decompensated cirrhosis and sarcopenia. Obesity may increase peritransplant morbidity but does not have an impact on long-term post-transplant survival. Bariatric surgery may be a feasible option in select patients before, during, or after liver transplantation. Use of weight loss drugs and/or endoscopic therapies for obesity management ultimately may play a role in liver transplant patients, but more research is needed to determine safety.

Safety of metabolic and bariatric surgery in obese patients with liver cirrhosis: a systematic review and meta-analysis

BACKGROUND

With the pandemic of obesity and the growing experience in metabolic and bariatric surgery (MBS), the number of patients with obesity and liver cirrhosis undergoing MBS is increasing.

OBJECTIVE

To analyze the morbidity and mortality following MBS in patients with obesity and liver cirrhosis.

SETTING

Systematic review and meta-analysis.

METHODS

The published literature was systematically reviewed, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, for studies reporting outcomes of MBS among patients with liver cirrhosis. The predetermined endpoints were the overall complication after MBS, intraoperative complications, liver-related complications after MBS, all-cause 90-day mortality after MBS, and liver-related mortality post-MBS. The pooled weighted proportions for each of the endpoints was calculated using random effect meta-analysis.

RESULTS

A total of 18 studies, including 471 patients with obesity and liver cirrhosis undergoing MBS, qualified for the final quantitative analysis. The mean age and mean body mass index (BMI) of the pooled patient cohort were 50.2 years and 47.2 kg/m². The pooled weighted proportions of the overall post-MBS complications, intraoperative complications, liver-related complications, overall 90-day mortality, and liver failure related mortality post MBS were 22.14% (CI_95%: 15.43%-29.55%), .08% (CI_95%: 0%-1.02%), 4.62% (CI_95%: 1.27%-9.30%), 0% (CI_95%: 0%-.44%), .08% (CI_95%: 0%-1.03%), respectively. Significantly lower postoperative complications were noted with sleeve gastrectomy (10.08% [95%CI: 5.14%-16%]) compared with Roux-en-Y gastric bypass (31.53% [95%CI: 18.62%-45.68%]; (P = .02).

CONCLUSION

We found an overall low postoperative surgical and liver-related mortality post MBS among patients with obesity and liver cirrhosis. The overall postoperative complications and liver-related complications were higher among patients with liver cirrhosis than in noncirrhotic patients. Sleeve gastrectomy showed lower postoperative complications compared with Roux-en-Y gastric bypass.

Improving Outcomes of Bariatric Surgery in Patients With Cirrhosis in the United States: A Nationwide Assessment

INTRODUCTION

With increasing burden of obesity and liver disease in the United States, a better understanding of bariatric surgery in context of cirrhosis is needed. We described trends of hospital-based outcomes of bariatric surgery among cirrhotics and determined effect of volume status and type of surgery on these outcomes.

METHODS

In this population-based study, admissions for bariatric surgery were extracted from the National Inpatient Sample using International Classification of Diseases, 9th and 10th Revision, Clinical Modification codes from 2004 to 2016 and grouped by cirrhosis status, type of bariatric surgery, and center volume. In-hospital mortality, complications, and their trends were compared between these groups using weighted counts, odds ratios [ORs], and logistic regression.

RESULTS

Among 1,679,828 admissions for bariatric surgery, 9,802 (0.58%) had cirrhosis. Cirrhosis admissions were more likely to be in white men, had higher Elixhauser Index, and higher in-hospital complications rates including death (1.81% vs 0.17%), acute kidney injury (4.5% vs 1.2%), bleeding (2.9% vs 1.1%), and operative complications (2% vs 0.6%) (P < 0.001 for all) compared to those without cirrhosis. Overtime, restrictive surgeries have grown in number (12%-71%) and complications rates have trended down in both groups. Cirrhotics undergoing bariatric surgery at low-volume centers (<50 procedures per year) and nonrestrictive surgery had a higher inpatient mortality rate (adjusted OR 4.50, 95% confidence interval 3.14-6.45, adjusted OR 4.00, 95% confidence interval 2.68-5.97, respectively).

DISCUSSION

Contemporary data indicate that among admissions for bariatric surgery, there is a shift to restrictive-type surgeries with an improvement in-hospital complications and mortality. However, patients with cirrhosis especially those at low-volume centers have significantly higher risk of worse outcomes (see Visual abstract, Supplementary Digital Content, http://links.lww.com/AJG/B648).

Nonalcoholic fatty liver disease and type 2 diabetes: where do Diabetologists stand?

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide. The increasing prevalence of NAFLD mirrors that of obesity and type 2 diabetes over the last two decades.

MAIN

In a two-way pathophysiologic relationship, NAFLD increases the risk of developing type 2 diabetes, while the latter promotes the progression of simple fatty liver to a more advanced form called nonalcoholic steatohepatitis (NASH). NASH increases the risk of cirrhosis and hepatocellular carcinoma (HCC), which may require liver transplantation. With the absence of FDA-approved medications for NAFLD treatment, lifestyle intervention remains the only therapy. Lately, extensive research efforts have been aimed at modifying NASH fibrosis and developing noninvasive screening methods.

CONCLUSION

We highlight the pathophysiologic relationships between NAFLD and type 2 diabetes, discuss disease recognition, models of care, and current and emerging therapies for NASH treatment.

Systematic Literature Review and Critical Appraisal of Health Economic Models Used in Cost-Effectiveness Analyses in Non-Alcoholic Steatohepatitis: Potential for Improvements

BACKGROUND

Non-alcoholic steatohepatitis (NASH) is a severe, typically progressive form of non-alcoholic fatty liver disease (NAFLD). The global prevalence of NASH is increasing, driven partly by the global increase in obesity and type 2 diabetes mellitus (T2DM), such that NASH is now a leading cause of cirrhosis. There is currently an unmet clinical need for efficacious and cost-effective treatments for NASH; no pharmacologic agents have an approved indication for NASH.

OBJECTIVE

Our objective was to summarise and critically appraise published health economic models of NASH, to evaluate their quality and suitability for use in the assessment of novel treatments for NASH, and to identify knowledge gaps, challenges and opportunities for future modelling.

METHODS

A systematic literature review was performed using the MEDLINE, Embase, Cochrane Library and EconLit databases to identify published health economic analyses in patients with NAFLD or NASH. Supplementary hand searches of grey literature were also performed. Articles published up to November 2019 were included in the review. Quality assessment of identified studies was also performed.

RESULTS

A total of 19 articles comprising 16 unique models including either NAFLD as a whole or NASH alone were included in the review. Structurally, most models had a state-transition component; in terms of health states, two different approaches to early disease states were used, modelling either progression through fibrosis stages or NAFLD/NASH-specific health states. Conditions that frequently co-exist with NASH, such as obesity, T2DM and cardiovascular disease were not captured in models identified here. Late-stage complications such as cirrhosis, decompensated cirrhosis and hepatocellular carcinoma were consistently included, but input data (e.g. costs, utilities and transition probabilities) for late-stage complications were frequently sourced from other liver disease areas. The quality of included studies was heterogenous, and only a small proportion of studies reported internal and external validation processes.

CONCLUSION

The health economic models identified in this review are associated with limitations primarily driven by a lack of NASH-specific data. Identified models also largely overlooked the intricate association between NASH and other conditions, including obesity and T2DM, and did not capture the increased risk of cardiovascular events associated with NASH. High-quality, transparent, validated health economic models of NASH will be required to evaluate the cost effectiveness of treatments currently in development, particularly compounds that may target other non-hepatic outcomes.

Comprehensive Health-State Utilities in Contemporary Patients With Cirrhosis

Cost‐effectiveness analysis depends on generalizable health‐state utilities. Unfortunately, the available utilities for cirrhosis are dated, may not reflect contemporary patients, and do not capture the impact of cirrhosis symptoms. We aimed to determine health‐state utilities for cirrhosis, using both the standard gamble (SG) and visual analog scale (VAS). We prospectively enrolled 305 patients. Disease severity (Child‐Pugh [Child] class, Model for End‐Stage Liver Disease with sodium [MELD‐Na] scores), symptom burden (sleep quality, cramps, falls, pruritus), and disability (activities of daily living) were assessed. Multivariable models were constructed to determine independent clinical associations with utility values. The mean age was 57 ± 13 years, 54% were men, 30% had nonalcoholic steatohepatitis, 26% had alcohol‐related cirrhosis, 49% were Child class A, and the median MELD‐Na score was 12 (interquartile range [IQR], 8‐18). VAS displayed a normal distribution with a wider range than SG. The Child‐specific SG‐derived utilities had a median value of 0.85 (IQR, 0.68‐0.98) for Child A, 0.78 (IQR, 0.58‐0.93) for Child B, and 0.78 (IQR, 0.58‐0.93) for Child C. VAS‐derived utilities had a median value of 0.70 (IQR, 0.60‐0.85) for Child A, 0.61 (IQR, 0.50‐0.75) for Child B, and 0.55 (IQR, 0.40‐0.70) for Child C. VAS and SG were weakly correlated (Spearman's rank correlation coefficient, 0.12; 95% confidence interval, 0.006‐0.23). In multivariable models, disability, muscle cramps, and MELD‐Na were significantly associated with SG utilities. More clinical covariates were significantly associated with the VAS utilities, including poor sleep, MELD‐Na, disability, falls, cramps, and ascites. Conclusion: We provide health‐state utilities for contemporary patients with cirrhosis as well as estimates of the independent impact of specific symptoms on each patient’s reported utility.

Impact of laparoscopic sleeve gastrectomy on fibrosis stage in patients with child-A NASH-related cirrhosis

PURPOSE

Bariatric surgery can improve non-alcoholic fatty liver disease (NAFLD). Yet data on the effect on fibrosis are insufficient and controversial. This work endeavored to evaluate the safety of laparoscopic sleeve gastrectomy (LSG) in cases that have compensated non-alcoholic steatohepatitis (NASH)-related cirrhosis and its impact on fibrosis stage.

METHODS

The current prospective work involved 132 cases with Child-A NASH-related cirrhosis suffering from morbid obesity scheduled for LSG. They were subjected to preoperative assessment, wedge biopsy, and ultrasound-guided true-cut liver biopsy after 30 months. Patients were included if proved to have F4 fibrosis initially. The liver condition was assessed based on the NALFD Activity Score (NAS). The primary outcome measure was the impact of LSG on fibrosis stage and its relation to weight loss.

RESULTS

The analysis included only 71 patients who completed the 30-month follow-up period. By the end of the follow-up interval, there was a substantial weight loss with a reasonable resolution of comorbidities. The median NAS decreased significantly from 6 (1-8) to 3 (0-6) after surgery. Fibrosis score regressed to F2 in 19 patients (26.8%) and F3 in 29 (40.8%). Patients with improved scores had a significantly higher amount of weight loss (p < 0.001). Improvement was more frequent in males (p = 0.007). By 30 months after treatment, 53.8% of cases with borderline NASH and 36.8% of those with probable NASH showed complete resolution, and 44.7% of patients with NASH showed improvement. Steatosis improved in 74.6% of patients (p < 0.001).

CONCLUSION

In patients with NASH-related liver cirrhosis of Child class A, LSG may be a secure approach for the management of morbid obesity. It has a long-term benefit for both obesity and liver condition with significant improvement of steatosis, steatohepatitis, and fibrosis.

Concurrent nonalcoholic fatty liver disease and type 2 diabetes: diagnostic and therapeutic considerations

Introduction: The relationship between nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM) is complex and bidirectional. NAFLD increases the risk of incident diabetes and is very prevalent in T2DM patients and T2DM is an aggravating factor for NAFLD. Timely T2DM diagnosis and treatment in subjects with NAFLD and diagnosis, staging and treatment of NAFLD in those with T2DM are critical issues. Areas covered: PubMed/MEDLINE was searched for articles related to concomitant occurrence of NAFLD and T2DM between January 2013 and May 2019. Areas covered included epidemiological, diagnostic and therapeutic aspects. Expert opinion: there is a need for increased awareness on NAFLD adding liver disease as an end-organ complication of T2DM. Emphasis on use of simple non-invasive tools to triage patients with potentially severe liver disease should be made. Management of patients with NAFLD and T2DM relies on lifestyle optimization to achieve significant weight loss. Currently, there is no drug approved for treatment of NAFLD in patients with T2DM although Vitamin E and pioglitazone might be used in selected patients. Approved diabetic medications hold promise for NAFLD treatment and several liver-specific drugs are in evaluation clinical trials. A combination approach will likely represent the future of NAFLD therapeutics.

How Would You Manage This Patient With Nonalcoholic Fatty Liver Disease?: Grand Rounds Discussion From Beth Israel Deaconess Medical Center

Nonalcoholic fatty liver disease (NAFLD), a common diagnosis in the United States and other developed countries, has been increasing in prevalence. The American Association for the Study of Liver Diseases recently published updated practice guidelines for diagnosing and managing NAFLD, including the following recommendations: Routine screening for NAFLD in high-risk groups is not advised because of uncertainties surrounding test and treatment options, along with a lack of knowledge about cost-effectiveness and long-term benefits. Noninvasive studies, including biomarkers from laboratory tests and liver stiffness measured through elastography, are clinically useful tools for identifying advanced fibrosis in patients with NAFLD. Liver biopsy should be considered in patients with NAFLD who are at increased risk for nonalcoholic steatohepatitis (NASH) or advanced fibrosis. Weight loss of at least 3% to 5% generally reduces NASH, but greater weight loss (7% to 10%) is needed to improve most histopathologic features, including fibrosis. Pharmacologic therapies (such as pioglitazone and vitamin E) should be considered only in patients with biopsy-proven NASH. Patients with NAFLD should not consume heavy amounts of alcohol, although insufficient data exist to provide advice about other levels of alcohol use. Here, 2 clinicians with expertise in this area debate whether to screen for NAFLD in primary care, how to monitor patients with NAFLD, and what interventions should be used to manage this condition.