Cost-utility analysis of nonalcoholic steatohepatitis screening

Ultrasound-derived fat fraction for diagnosing hepatic steatosis: a systematic review and meta-analysis

OBJECTIVE

To perform a systematic review and meta-analysis to evaluate the diagnostic performance of Ultrasound-Derived Fat Fraction (UDFF) in detecting hepatic steatosis using Magnetic Resonance Imaging-Proton Density Fat Fraction (MRI-PDFF) as the reference standard.

MATERIALS AND METHODS

Relevant databases were searched through November 2024. Studies that evaluated the UDFF to detect hepatic steatosis using MRI-PDFF as the reference standard met the inclusion criteria. Our primary outcome was the sensitivity and specificity of UDFF compared to MRI-PDFF in distinguishing steatosis from non-steatosis. Analyses were performed using a bivariate random-effects approach, and heterogeneity was considered substantial if I2 > 50%. A sensitivity analysis was performed to detect potential studies that contribute to heterogeneity.

RESULTS

Nine studies comprising 1150 patients (mean age range, 14-62 years; 51.2% women) were included. Eight studies were performed using the same vendor platform. The pooled sensitivity of UDFF for detecting hepatic steatosis was 90.4% (95% CI: 84.0%, 94.4%), and the pooled specificity was 83.8% (95% CI: 75.1%, 89.8%). The AUC for the summary receiver-operating characteristic curve was 0.93 (95% CI: 0.83, 0.95). Heterogeneity among the studies was low (I² = 22.2%).

CONCLUSION

UDFF demonstrates high sensitivity and specificity for detecting hepatic steatosis, supporting its value as a noninvasive tool for screening.

KEY POINTS

Question Small individual studies suggest that US-Derived Fat Fraction (UDFF) may effectively detect hepatic steatosis compared to MRI, but no meta-analysis has been performed. Findings In nine studies including 1150 patients, UDFF demonstrated high pooled sensitivity (90.4%) and specificity (83.8%) relative to MRI with low between-study heterogeneity. Clinical relevance UDFF demonstrates high diagnostic accuracy compared with MRI, supporting its use as a noninvasive tool with potentially lower cost and wider availability for large-scale screening of hepatic steatosis.

Utility and cost-effectiveness of LiverMultiScan for MASLD diagnosis: a real-world multi-national randomised clinical trial

BACKGROUND

Increasing prevalence of metabolic dysfunction-associated liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH) poses a growing healthcare burden. Noninvasive diagnostic tools to replace liver biopsy are urgently needed. We investigated the utility and cost-effectiveness of including multiparametric magnetic resonance imaging (mpMRI) to the management of adults with suspected MASLD multi-nationally.

METHODS

RADIcAL-1, a 1:1 randomised controlled trial (standard-of-care [SoC] vs. imaging arm [IA; SoC+mpMRI]) included 802 participants from Germany, Netherlands, Portugal and UK. Wilcoxon-rank tests were used to compare access to healthcare practitioners, patient assessments and proportion of patients with a diagnosis (%diagnosis). Liver fat and disease activity (corrected T1 [cT1]) were used to identify patients not requiring biopsy in the imaging arm. Primary endpoint was mpMRI cost-effectiveness and improvement in resource use (visits avoided) using mpMRI.

RESULTS

mpMRI is cost-effective with an ICER of €4968/QALY gained. 403 were randomised to IA and 399 to SoC. SoC has significantly more specialist appointments (p = 0.015) and patient assessments (p < 0.001). Across all involved hospitals, %diagnosis is significantly higher in the imaging arm (p = 0.0012). cT1 correctly classifies 50% of patients without MASH with fibrosis and can avoid biopsy. Including all costs, the imaging arm incurs higher short-term per-patient healthcare expenditure compared to the SoC arm (€1,300 vs. €830).

CONCLUSION

Adding mpMRI to SoC for the management of adults with suspected MASLD multi-nationally is cost-effective, enhances rate of diagnosis multi-nationally and increases rate of diagnosis without increasing other liver-related health care resource use. Due to the need for standardisation of SoC, widespread use can support optimisation of the MASLD clinical pathway and improve long-term patient management.

Economic evaluation of non-invasive test pathways for high-risk metabolic dysfunction-associated steatotic liver disease (MASLD) in the United Kingdom (UK)

INTRODUCTION AND OBJECTIVES

Non-invasive tests (NITs) identifying high-risk MASLD in primary care is suggested but, these strategies cost-effectiveness remain uncertain in the United Kingdom (UK).

MATERIALS AND METHODS

A cost-utility/budget impact model was developed for cost-effectiveness evaluation of two screening strategies (1) FIB-4 followed by Enhanced Liver Fibrosis (ELF) (FIB-4/ELF); (2) FIB-4 followed by Transient Elastography (FIB-4/TE) compared to standard of care (SoC). A cohort of primary care MASLD patients with an advanced fibrosis prevalence of 4.20 % was simulated. A decision tree classified patients as true positives, false positives, true negatives, or false negatives based on NIT diagnostic accuracy, followed by a 3-year Markov model to estimate costs and quality-adjusted life years (QALYs). The model included 11 health states: MASLD, fibrosis stages (F0-F3), cirrhosis, decompensated cirrhosis, liver transplant, and death. Costs came from the National Tariff, National Schedule of Costs and Personal Social Services Research Unit.

RESULTS

SoC had a false diagnosis rate of 36.26 %, while FIB-4 with ELF or TE reduced false positive rates to 23.20 % and 20.91 %, respectively. Compared to 112,807 unnecessary hepatology referrals under SoC, FIB-4/ELF or FIB-4/TE reduced unnecessary referrals by 38,031 (33.71 %) and 45,767 (40.57 %), respectively. Both strategies demonstrated cost-effectiveness relative to SoC with total cost per patient of GBP 983.37 for FIB-4/TE, GBP 993.15 for FIB-4/ELF compared to SoC, GBP 1,014.15.

CONCLUSIONS

Sequential NIT screening strategies, combining FIB-4 with ELF or TE, are cost-saving, reduce unnecessary hepatology referrals, and offer an efficient (improve outcomes and reduce healthcare costs) approach for managing high-risk MASLD in UK primary care.

Determining the sensitivity and specificity of the calculated fatty liver index in comparison with ultrasound

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disease in human history and it is expected to surpass other causes of liver disease mortality by 2030. Therefore, finding an alternative way to diagnose steatosis in the early stage when imaging modalities are not available is crucial. This study decided to validate the optimal cut-off points and the sensitivity and specificity of the Fatty Liver Index (FLI) based on the Iranian population compared to ultrasonography.

METHODS

The data of 367 individuals, 108 males and 259 females over 35, were analyzed. Hepatic steatosis was identified by ultrasound. FLI was determined from waist circumference, gamma-glutamyl transferase, triglyceride, and body mass index data. The receiver operating characteristic curve (ROC) was used to determine the best FLI index cut point for diagnosing nonalcoholic fatty liver. The sensitivity and specificity indices were calculated for the determined cut point.

RESULTS

The AUC of the FLI index in diagnosing NAFLD in the total population was 0.733 (95% CI: 0.68-0.77, specificity = 0.6705, sensitivity = 0.7320) with the optimal COP of 40.6. There was a statistically significant association between non-alcoholic liver disease and FLI-based ultrasound (p < 0.0001). Furthermore, the sex-specific optimal COPs of FLI was 33.4, specificity = 0.6071, sensitivity = 0.8462 in men vs. 27.8, sensitivity = 0.8233, specificity = 0.7655 in women.

CONCLUSION

FLI is a reliable tool for identifying individuals with NAFLD. It has the potential to aid in detecting and managing this condition in large-scale populations while other methods are not available. We also determine an optimal COP of 40.6 with sensitivity and specificity of 73.20% and 67.05% in the general population, respectively.

Cost-Effectiveness Analysis of Innovative Therapies for Patients with Non-Alcoholic Fatty Liver Disease

OBJECTIVE

Currently there are no disease-specific approved therapies for non-alcoholic fatty liver (NAFL) and non-alcoholic steatohepatitis (NASH); however, several treatments are under development. This study aimed to estimate the cost-effectiveness of hypothetical innovative therapies compared with lifestyle intervention alone and combined with pioglitazone, and assess the health economic consequences of their future availability for patients.

METHODS

A Markov cohort model was developed, considering fourteen disease health states and one absorbing state representing death. Transition probabilities, costs, utilities, and treatment efficacy were based on published data and assumptions. Four treatment strategies were considered, including two existing therapies (lifestyle intervention, small molecule treatment) and two hypothetical interventions (biological and curative therapy). The analysis was performed from the US third-party payer perspective.

RESULTS

The curative treatment with the assumed efficacy of 70% of patients cured and assumed price of $500,000 was the only cost-effective option. Although it incurred higher costs (a difference of $188,771 vs. lifestyle intervention and $197,702 vs. small molecule), it generated more QALYs (a difference of 1.58 and 1.38 QALYs, respectively), resulting in an ICER below the willingness-to-pay threshold of $150,000 per QALY. The sensitivity analyses showed that the results were robust to variations in model parameters.

CONCLUSIONS

This study highlighted the potential benefits of therapies aimed at curing a disease rather than stopping its progression. Nonetheless, each of the analyzed therapies could be cost-effective compared with lifestyle intervention at a relatively high price.

Economic evaluation of non-invasive liver tests for the diagnosis of liver fibrosis in chronic liver diseases: a systematic review protocol

OBJECTIVE

The objective of this review is to determine the costs and benefits of non-invasive liver tests vs liver biopsy in patients with chronic liver diseases.

INTRODUCTION

Hepatic diseases can lead to liver fibrosis, cirrhosis, and hepatocellular carcinoma. In the past, liver biopsy was the only option for diagnosing fibrosis degree. Liver biopsy is an invasive procedure that depends on the sample size to be able to deliver an accurate diagnosis. In recent years, non-invasive liver tests have been increasingly used to estimate liver fibrosis degree; however, there is a lack of economic assessments of technology implementation outcomes.

INCLUSION CRITERIA

This review will include partial (cost studies) and complete economic evaluation studies on hepatitis B, hepatitis C, alcoholic liver disease, and non-alcoholic fatty liver disease that compare non-invasive liver tests with liver biopsies. Studies published in English, French, Spanish, German, Italian, or Portuguese will be included. No date limits will be applied to the search.

METHODS

This review will identify published and unpublished studies. Published studies will be identified using MEDLINE (PubMed), Cochrane Library (CENTRAL), Embase, Web of Science, Scopus, and LILACS. Sources of unpublished studies and gray literature will include sources from health technology assessment agencies, clinical practice guidelines, regulatory approvals, advisories and warnings, and clinical trial registries, as well as Google Scholar. Two independent reviewers will screen and assess studies, and extract and critically appraise the data. Data extracted from the included studies will be analyzed and summarized to address the review objective using narrative text, and the JBI dominance ranking matrix.

REVIEW REGISTRATION

PROSPERO CRD42023404278.

Effect of MAFLD on albuminuria and the interaction between MAFLD and diabetes on albuminuria

OBJECTIVE

To investigate the effects of metabolic associated fatty liver disease (MAFLD) on chronic kidney disease (CKD) and abnormal albuminuria and the interaction between MAFLD and diabetes on abnormal albuminuria.

METHODS

Data of participants in the American 2017-2018 National Health and Nutrition Examination Survey were analyzed. Hepatic steatosis was defined as median controlled attenuation parameter ≥248 dB/m, which was measured by ultrasound transient elastography. MAFLD was defined by evidence of hepatic steatosis on ultrasound in addition to any metabolic dysregulation. Hepatic fibrosis was detected by FibroScan and quantified by parameter of stiffness (E). Hepatic fibrosis was defined as E ≥ 9.7 kPa. As component of CKD, reduced estimated glomerular filtration rate (eGFR) was defined as<60 mL/min/1.73 m2 and abnormal albuminuria was defined as urinary albumin-to-creatinine ratio ≥ 30 mg/g.

RESULTS

Data pertaining to 5119 participants were included in the analysis, with 40.6% hepatic normal, 52.1% MAFLD, and 7.2% hepatic fibrosis. Multivariable regression analyses showed that for abnormal albuminuria, the odds ratio (OR) was 0.82 (0.65-1.04) for MAFLD group and 1.73 (1.14.-,2.63) for hepatic fibrosis group, both taking the hepatic healthy group as reference. As for reduced eGFR, the OR was 0.68 (0.51-0.92) for MAFLD group and 0.93 (0.56-1.53) for hepatic fibrosis group. Diabetes was significantly related to greater risk of abnormal albuminuria (3.04 [2.70-3.42]) and reduced eGFR (1.53 [1.33-1.77]). With regard to the prevalence of abnormal albuminuria, the OR was 1.64 (1.03-2.60) for those with hepatic fibrosis only, 3.30 (2.80-3.89) for those with diabetes only, and 5.05 (3.30-7.72) for those with both two conditions. But there were neither additive interaction (relative excess risk due to interaction 0.56 [-1.41-.53], p = .577) nor multiplicative interaction (OR 0.81 [0.45-1.47], p = .492) between hepatic fibrosis and diabetes on the prevalence of abnormal albuminuria.

CONCLUSION

MAFLD with hepatic fibrosis is an independent risk factor for abnormal albuminuria, but it does not have interaction with diabetes on abnormal albuminuria.

Estimating utility values for non-alcoholic steatohepatitis health states: a discrete choice experiment

Background: This study estimated utility values for non-alcoholic steatohepatitis (NASH). Previous studies have assumed that health-related quality of life does not vary between the early stages of NASH. Materials & Methods: Discrete choice experiment (DCE) surveys estimated the value of avoiding fibrosis progression. Patients also completed the EQ-5D-5L. Marginal rates of substitution estimated utility change associated with fibrosis progression. Results: DCE surveys were completed by the UK general public (n = 520) and patients with NASH (n = 154). The utility decline between fibrosis stages F1 and F4 decompensated was between -0.521 to -0.646 (depending on method). Conclusion: Three methods were used to estimate utilities for NASH, each one showed sensitivity to advancing fibrosis, including in the early stages, which is often considered asymptomatic.

Comparison of Radiologists and Deep Learning for US Grading of Hepatic Steatosis

Background Screening for nonalcoholic fatty liver disease (NAFLD) is suboptimal due to the subjective interpretation of US images. Purpose To evaluate the agreement and diagnostic performance of radiologists and a deep learning model in grading hepatic steatosis in NAFLD at US, with biopsy as the reference standard. Materials and Methods This retrospective study included patients with NAFLD and control patients without hepatic steatosis who underwent abdominal US and contemporaneous liver biopsy from September 2010 to October 2019. Six readers visually graded steatosis on US images twice, 2 weeks apart. Reader agreement was assessed with use of κ statistics. Three deep learning techniques applied to B-mode US images were used to classify dichotomized steatosis grades. Classification performance of human radiologists and the deep learning model for dichotomized steatosis grades (S0, S1, S2, and S3) was assessed with area under the receiver operating characteristic curve (AUC) on a separate test set. Results The study included 199 patients (mean age, 53 years ± 13 [SD]; 101 men). On the test set (n = 52), radiologists had fair interreader agreement (0.34 [95% CI: 0.31, 0.37]) for classifying steatosis grades S0 versus S1 or higher, while AUCs were between 0.49 and 0.84 for radiologists and 0.85 (95% CI: 0.83, 0.87) for the deep learning model. For S0 or S1 versus S2 or S3, radiologists had fair interreader agreement (0.30 [95% CI: 0.27, 0.33]), while AUCs were between 0.57 and 0.76 for radiologists and 0.73 (95% CI: 0.71, 0.75) for the deep learning model. For S2 or lower versus S3, radiologists had fair interreader agreement (0.37 [95% CI: 0.33, 0.40]), while AUCs were between 0.52 and 0.81 for radiologists and 0.67 (95% CI: 0.64, 0.69) for the deep learning model. Conclusion Deep learning approaches applied to B-mode US images provided comparable performance with human readers for detection and grading of hepatic steatosis. Published under a CC BY 4.0 license. Supplemental material is available for this article. See also the editorial by Tuthill in this issue.

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.

Cost-effectiveness analysis of noninvasive tests to identify advanced fibrosis in non-alcoholic fatty liver disease

BACKGROUND

Advanced fibrosis is associated with end-stage liver disease (ESLD) and mortality in NAFLD. As treatments specifically targeted at NAFLD are lacking, patient management focuses on surveillance for early detection of complications related to end-stage liver disease. Although current and emerging diagnostic tools for the detection of advanced fibrosis are crucial for surveillance, their added value is unclear. The aim of this study was to evaluate the costs and health outcomes of noninvasive tests in patient management strategies for diagnosing advanced fibrosis in NAFLD patients.

METHOD

A decision analytical model was developed to evaluate 13 patient management strategies, including a no-testing strategy and 12 diagnostic algorithms with noninvasive tests (fibrosis 4- score, enhanced liver fibrosis, vibration controlled transient elastography), and liver biopsy. Model inputs were synthesized from the literature and Swedish registries. Lifetime health care costs, life years, quality-adjusted life years, clinical outcomes, and incremental cost-effectiveness ratios were calculated for a cohort of 55-year-old patients diagnosed with NAFLD.

RESULT

The cost per quality-adjusted life year was above €50 000 for all diagnostic algorithms compared to no-testing. The cost per quality-adjusted life year of the most promising diagnostic algorithm (fibrosis 4- score, enhanced liver fibrosis, vibration controlled transient elastography, and liver biopsy) was ∼ €181 000 compared with no testing. Sensitivity analysis indicated that if treatment slowed down disease progression, the value of testing increased.

CONCLUSION

The result questions the overall value of comprehensive diagnostic testing in a broad NAFLD population in current routine clinical care. The role of noninvasive tests may change if evidence-based treatments to slow down disease progression emerge.

Screening for At-Risk Nonalcoholic Fatty Liver Disease in the Primary Care Setting

While nonalcoholic fatty liver disease is a leading cause of end-stage liver disease, most patients with nonalcoholic fatty liver disease do not develop cirrhosis and its complications. Therefore, risk stratification using inexpensive, noninvasive screening modalities is critical to avoid overdiagnosis and overtreatment of a large proportion of the population. In this review, we discuss the data supporting screening and current professional society recommendations on this topic. Screening for at-risk nonalcoholic fatty liver disease is recommended in patients with risk factors including diabetes, the metabolic syndrome, hepatic steatosis, and elevated aminotransferases. Screening typically consists of noninvasive testing using serum biomarkers followed by elastography using specialized imaging modalities. This sequential screening approach accurately identifies both high- and low-risk patients and is cost-effective when applied to at-risk populations. In conclusion, screening for advanced nonalcoholic fatty liver disease in the primary care setting is a crucial part of identifying high-risk patients who may benefit from aggressive intervention while avoiding overtreatment of patients at low risk of liver-related complications.

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.

New FIB-4 and NFS cutoffs to guide sequential non-invasive assessment of liver fibrosis by magnetic resonance elastography in NAFLD

INTRODUCTION AND OBJECTIVES

Liver fibrosis is an important prognosis marker in non-alcoholic fatty liver disease (NAFLD). Biopsy has been considered the gold-standard method for measuring liver fibrosis; however, it is an invasive procedure. Non-invasive diagnostic tools have been developed, such as clinical scores and magnetic resonance elastography (MRE), which is the most accurate non-invasive method to determine liver fibrosis. Thus, the aim was to determine the NAFLD Fibrosis Score (NFS) and the Fibrosis-4 Score (FIB-4) cut-off points that best identify NAFLD patients at risk for developing liver fibrosis.

PATIENTS AND METHODS

Single-center cross-sectional study with prospective recruitment of NAFLD (training-cohort) and MAFLD (validation-cohort) patients undergoing MRE. The NFS and the FIB-4 cut-off points that best-differentiated patients with fibrosis, using the MRE as the standard method, were determined.

RESULTS

Two cohorts were analyzed, a training cohort that included the initial 183 patients with NAFLD and a validation cohort that included 289 patients. In the training cohort, 60.1% had mild steatosis and 11.5% had liver fibrosis ≥ F1 by MRE. ROC curves were developed for FIB-4 and NFS, and the cut-off points chosen were 1.505 (sensitivity=85% and specificity=86%) for FIB-4 and -0.835 (sensitivity=100% and specificity=70%) for NFS, showing greater specificity than the cut-off points currently used (51% and 76%, respectively). The two cohorts exhibited similar characteristics and similar sensitivity and specificity results for the chosen cut-off points.

CONCLUSIONS

This study has shown cut-off points with greater specificity and excellent sensitivity to guide the indication for further liver evaluation by MRE in NAFLD patients.

Association Between Different Parameters of Adipose Distribution and Transient Elastography-Assessed Hepatic Steatosis in American Adults with Diabetes, Prediabetes and Normal Glucose Tolerance

OBJECTIVE

To investigate the association between adipose distribution and hepatic steatosis in American adults and to assess whether this association varies among different blood glucose states.

METHODS

Data from the American National Health and Nutrition Examination Survey (NHANES) 2017-2018 were analyzed. The subjects were divided into three groups: diabetes, prediabetes and normal glucose tolerance (NGT). Hepatic steatosis was quantified by median controlled attenuation parameter (CAP), which was measured by ultrasound transient elastography. Total abdominal fat volume, visceral adipose tissue (VAT) volume, total percent fat, trunk percent fat, android percent fat and android to gynoid ratio (AGR) was measured by dual-energy X-ray absorptiometry (DXA).

RESULTS

Data pertaining to 2986 participants (1581 with hepatic steatosis) were included in the analysis. In the NGT group, the proportion of S0 (<5% of the hepatocytes with fatty infiltration) was 58.9%, and 25.2% for S3 (≥66% of the hepatocytes with fatty infiltration). In contrast, the proportion of S0 was 11.1%, while S3 accounts for as high as 68.7% in the diabetes group. In the NGT group, all parameters of fat distribution revealed a positive relation with the occurrence of hepatic steatosis (p<0.05) except total percent fat (p=0.872) after adjusting for confounding factors. In the prediabetes group, VAT volume, trunk percent fat, android percent fat and AGR had significant influence on hepatic steatosis (p<0.05). As for diabetes, only AGR remained significantly correlated with hepatic steatosis (p=0.004).

CONCLUSION

For NGT individuals, high level of total abdominal fat volume, VAT volume, trunk percent fat, android percent fat and AGR all can be used to predict hepatic steatosis. For diabetes, only AGR can predict hepatic steatosis among the surveyed parameters of adipose distribution.

Evaluation of emerging NASH therapies: the impact of treatment efficacy profiles on long-term health outcomes

Aim: Evaluations of nonalcoholic steatohepatitis (NASH) treatments require predicting lifetime outcomes from short-term clinical trials. Materials & methods: A Markov model with NASH fibrosis stages F0-F3, NASH resolution, compensated cirrhosis (F4/CC), and liver-related complication (LRC) states was developed using literature-based standard of care (SoC) data. Hypothetical efficacy profiles were defined affecting resolution (100%-increase), fibrosis improvement (100% increase), or fibrosis worsening (50% decrease). Results: For the SoC, 10-year LRC rates increased with baseline fibrosis stage (F1: 3.0%; F2: 9.8%; F3: 27.2%; F4/CC: 64.9%). The fibrosis worsening profile reduced predicted 10-year LRC rates (F1: 1.9%; F2: 6.5%; F3: 19.1%; F4/CC: 55.0%) more than the resolution and fibrosis improvement profiles (F1: 2.6%/2.6%; F2: 8.5%/8.3%; F3: 23.3%/23.0%; F4/CC: NA/59.0%). Scenario analyses considered alternative SoC progression, treatment efficacy and treatment-stopping rules. Conclusion: Potential NASH efficacy profiles have differing impacts on predicted long-term outcomes, providing insights for future stakeholders.

Non-invasive diagnosis and staging of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is considered to be the hepatic manifestation of the metabolic syndrome and is characterized by ectopic accumulation of triglycerides in the cytoplasm of hepatocytes, i.e., steatosis. NAFLD has become the most common chronic liver disease, with an estimated global prevalence of 25%. Although the majority of NAFLD patients will never experience liver-related complications, the progressive potential of NAFLD is indisputable, with 5-10% of subjects progressing to cirrhosis, end-stage liver disease, or hepatocellular carcinoma. NAFLD patients with advanced fibrosis are at the highest risk of developing cardiovascular and cirrhosis-related complications. Liver biopsy has hitherto been considered the reference method for evaluation of hepatic steatosis and fibrosis stage. Given the limitations of biopsy for widescale screening, non-invasive tests (NITs) for assessment of steatosis and fibrosis stage, including serum-based algorithms and ultrasound- and magnetic resonance-based methods, will play an increasing role in the management of NAFLD patients. This comprehensive review presents the advantages and limitations of NITs for identification of steatosis and advanced fibrosis in NAFLD. The clinical implications of using NITs to identify and manage NAFLD patients are also discussed.

Real-world Comorbidity Burden, Health Care Utilization, and Costs of Nonalcoholic Steatohepatitis Patients With Advanced Liver Diseases

GOALS

This study evaluates the real-world comorbidity burden, health care resource utilization (HRU), and costs among nonalcoholic fatty liver disease/nonalcoholic steatohepatitis (NAFLD/NASH) patients with advanced liver diseases [compensated cirrhosis (CC), decompensated cirrhosis (DCC), liver transplantation (LT), hepatocellular carcinoma (HCC)].

BACKGROUND

NAFLD/NASH is a leading cause of liver diseases.

MATERIALS AND METHODS

Adult NAFLD/NASH patients were identified retrospectively from MarketScan Commercial claims (2006-2016). Following initial NAFLD/NASH diagnosis, advanced liver diseases were identified using the first diagnosis as their index date. Mean annual all-cause HRU and costs (2016 USD) were reported. Adjusted costs were estimated through generalized linear models. Cumulative costs were illustrated for patient subsets with variable follow-up for each stage.

RESULTS

Within the database, 485,774 NAFLD/NASH patients met eligibility criteria. Of these, 93.4% (453,564) were NAFLD/NASH patients without advanced liver diseases, 1.6% (7665) with CC, 3.3% (15,833) with DCC, 0.1% (696) with LT, and 0.1% (428) with HCC. Comorbidity burden was high and increased as patients progressed through liver disease severity stages. Compared with NAFLD/NASH without advanced liver diseases (adjusted costs: $23,860), the annual cost of CC, DCC, LT, and HCC were 1.22, 5.64, 8.27, and 4.09 times higher [adjusted costs: $29,078, $134,448, $197,392, and $97,563 (P<0.0001)]. Inpatient admissions significantly drove increasing HRU.

CONCLUSION

Study findings suggest the need for early identification and effective management of NAFLD/NASH patients to minimize comorbidity burden, HRU, and costs in the privately insured US population.

Assessment of the inter-platform reproducibility of ultrasound attenuation examination in nonalcoholic fatty liver disease

Purpose

This study aimed to assess the inter-platform reproducibility of ultrasound attenuation examination in patients with nonalcoholic fatty liver disease (NAFLD).

Methods

Between March 2021 and April 2021, patients with clinically suspected or known NAFLD were prospectively enrolled; each patient underwent ultrasound attenuation examinations with three different platforms (Attenuation Imaging [ATI], Canon Medical System; Tissue Attenuation Imaging [TAI], Samsung Medison; and Ultrasound-Guided Attenuation Parameter [UGAP], GE Healthcare) on the same day. The mean attenuation coefficient (AC) values of the three platforms were compared using repeated-measures analysis of variance with the Bonferroni correction. To evaluate inter-platform reproducibility, the AC values obtained for each platform were compared using Bland-Altman analysis with the calculation of 95% limits of agreement (LOA), intraclass correlation coefficients (ICCs), and coefficients of variation (CVs).

Results

Forty-six patients (23 men; mean age±standard deviation, 52.3±12.4 years) were enrolled. The mean AC values showed significant differences among the three platforms (0.75±0.12, 0.80±0.11, and 0.74±0.09 dB/cm/MHz for ATI, TAI, and UGAP, respectively; P<0.001). For inter-platform reproducibility, the 95% LOAs were -0.22 to 0.11 dB/cm/MHz between ATI and TAI, -0.17 to 0.18 dB/cm/MHz between ATI and UGAP, and -0.08 to 0.20 dB/cm/MHz between TAI and UGAP, respectively. The pairwise ICCs were 0.790-0.797 in terms of absolute agreement among the three platforms; the CVs were 8.23%-9.47%.

Conclusion

The AC values obtained from different ultrasound attenuation examination platforms showed significant differences, with significant inter-platform variability. Therefore, the AC values measured using different ultrasound attenuation examination techniques should not be used interchangeably for longitudinal follow-up of patients with NAFLD.

Non-alcoholic fatty liver disease: A patient guideline

This patient guideline is intended for all patients at risk of or living with non-alcoholic fatty liver disease (NAFLD). NAFLD is the most frequent chronic liver disease worldwide and comes with a high disease burden. Yet, there is a lot of unawareness. Furthermore, many aspects of the disease are still to be unravelled, which has an important impact on the information that is given (or not) to patients. Its management requires a close interaction between patients and their many healthcare providers. It is important for patients to develop a full understanding of NAFLD in order to enable them to take an active role in their disease management. This guide summarises the current knowledge relevant to NAFLD and its management. It has been developed by patients, patient representatives, clinicians and scientists and is based on current scientific recommendations, intended to support patients in making informed decisions.

Screening for nonalcoholic fatty liver disease-when, who and how?

Nonalcoholic fatty liver disease (NAFLD) is becoming a frequent liver disease, especially in patients with metabolic syndrome and especially in Western countries. Complications of NAFLD comprise progressive fibrosis, cirrhosis and hepatocellular carcinoma. NAFLD also represents an independent risk factor for cardiovascular disease, extrahepatic neoplasia and other organ damage, such as renal insufficiency. Given the epidemiological importance of the disease, new developments in specific treatment of the disease and the wide availability of noninvasive techniques in estimating steatosis and fibrosis, NAFLD should be subject to screening programs, at least in countries with a high prevalence of the disease. The review discusses prerequisites for screening, cost-effectiveness, current guideline recommendations, suitability of techniques for screening and propositions for the following questions: Who should be screened? Who should perform screening? How should screening be performed? It is time for a screening program in patients at risk for NAFLD.

Comparison of two-dimensional shear wave elastography, magnetic resonance elastography, and three serum markers for diagnosing fibrosis in patients with chronic hepatitis B: a meta-analysis

BACKGROUND

Two-dimensional shear wave elastography (2D-SWE), magnetic resonance elastography (MRE), aspartate transaminase-to-platelet ratio index (APRI), fibrosis index based on 4 factors (FIB-4), and King's score have been proposed for diagnosing fibrosis.

METHODS

Literature databases were searched until October 1st, 2020. The summary area under the receiver operating characteristic curve (AUROC), the summary diagnostic odds ratios, and the summary sensitivities and specificities were used to assess the performance of these noninvasive methods for staging fibrosis.

RESULTS

Our final data contained 72 studies. The prevalence of significant fibrosis, advanced fibrosis, and cirrhosis was 58.3%, 36.2%, and 20.5%, respectively, in chronic hepatitis B (CHB). For 2D-SWE and MRE, the summary AUROCs were 0.89 and 0.97, 0.95 and 0.97, and 0.94 and 0.97 for significant fibrosis, advanced fibrosis, and cirrhosis, respectively. The summary AUROCs using APRI and FIB-4 for detecting significant fibrosis, advanced fibrosis, and cirrhosis were 0.76 and 0.75, 0.74 and 0.77, and 0.77 and 0.82, respectively. The summary AUROCs of King's score for detecting significant fibrosis and cirrhosis were 0.77 and 0.83, respectively.

CONCLUSION

MRE and 2D-SWE may show the best diagnostic accuracy for predicting fibrosis in CHB. Among the three serum markers, King's score may be more useful for diagnosing fibrosis.

Non-invasive diagnosis of nonalcoholic fatty liver disease in patients with type 2 diabetes

Liver disease has emerged as a significant cause of death in people with type 2 diabetes (T2D). Due to a common underlying pathogenic mechanism, namely insulin resistance, T2D represents the main risk factor for nonalcoholic fatty liver disease (NAFLD), characterized by a buildup of fat in the liver. Globally, NAFLD is the most common liver disease, affecting a quarter of the general adult population. The development of nonalcoholic steatohepatitis (NASH) signifies an increased risk of liver fibrosis progression that can result in cirrhosis, hepatocellular carcinoma (HCC), and death. Liver fibrosis progression and development of cirrhosis is mostly asymptomatic until complications from decompensated end-stage liver disease arise. Traditionally, liver biopsy is used to diagnose NASH and stage fibrosis, however, it is invasive and costly. Non-invasive diagnostic alternatives include serum biomarkers and imaging techniques. Early identification of advanced liver fibrosis is pivotal to prompt initiation of targeted surveillance, including screening for HCC, as well as providing options for current and investigational therapeutic interventions to reduce fibrosis progression. This review gives an update on non-invasive diagnostic tools for NAFLD and liver fibrosis in the specific context of T2D, providing clinicians a pragmatic diagnostic approach to this frequent comorbidity in diabetes medicine.

The role of fibrosis index FIB-4 in predicting liver fibrosis stage and clinical prognosis: A diagnostic or screening tool?

This review evaluates the ability of the fibrosis index based on four factors (FIB-4) identifying fibrosis stages, long-time prognosis in chronic liver disease, and short-time outcomes in acute liver injury. FIB-4 was accurate in predicting the absence or presence of advanced fibrosis with cut-offs of 1.0 and 2.65 for viral hepatitis B, 1.45 and 3.25 for viral hepatitis C, 1.30 (<65 years), 2.0 (≥65 years), and 2.67 for non-alcoholic fatty liver disease (NAFLD), respectively, but had a low-to-moderate accuracy in alcoholic liver disease (ALD) and autoimmune hepatitis. It performed better in excluding fibrosis, so we built an algorithm for identifying advanced fibrosis by combined methods and giving work-up and follow-up suggestions. High FIB-4 in viral hepatitis, NAFLD, and ALD was associated with significantly high hepatocellular carcinoma incidence and mortality. Additionally, FIB-4 showed the ability to predict high-risk varices with cut-offs of 2.87 and 3.91 in cirrhosis patients and predict long-term survival in hepatocellular carcinoma patients after hepatectomy. In acute liver injury caused by COVID-19, FIB-4 had a predictive value for mechanical ventilation and 30-day mortality. Finally, FIB-4 may act as a screening tool in the secondary prevention of NAFLD in the high-risk population.

Clinical and economic burden of nonalcoholic steatohepatitis in Saudi Arabia, United Arab Emirates and Kuwait

Background and aims

The Middle East (ME) has a high prevalence of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH), driven by obesity and type-2 diabetes mellitus (T2DM). Studies in Saudi Arabia (KSA) and United Arab Emirates (UAE) predict an escalating impact of NAFLD/NASH, particularly advanced fibrosis due to NASH (AF-NASH), increasing cases of cirrhosis, liver cancer and death. The scale of this burden in other ME countries is unknown with no reports of NAFLD/NASH healthcare resource utilization (HCRU) or costs. We estimated the clinical and economic burden of NAFLD/NASH in KSA, UAE and Kuwait.

Methods

Markov models populated with country-specific obesity and T2DM prevalence data estimated numbers and progression of NAFLD/NASH patients from 2018 to 2030. Model inputs, assumptions and outputs were collected from literature, national statistics, and expert consensus.

Results

Over 13 years, the KSA model estimated cases increasing as follows: patients with fibrosis F0–3 doubled to 2.5 m, compensated and decompensated cirrhosis and hepatocellular carcinoma trebled to 212,000; liver failure or transplant patients increased four-fold to 4,086 and liver-related death escalated from < 10,000 to > 200,000. Similar trends occurred in UAE and Kuwait. Discounted lifetime costs of NASH standard-care increased totaling USD40.41 bn, 1.59 bn and 6.36 bn in KSA, UAE (Emiratis only) and Kuwait, respectively. NASH-related costs in 2019 comprised, respectively, 5.83%, 5.80% and 7.66% of national healthcare spending.

Conclusions

NASH, especially AF-NASH, should be considered a higher priority in ME Public Health policy. Our analyses should inform health policy makers to mitigate the enormity of this escalating regional burden.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12072-021-10182-x.

The Impact of Nonalcoholic Fatty Liver Disease in Primary Care: A Population Health Perspective

Nonalcoholic fatty liver disease (NAFLD) is the leading cause of liver disease worldwide, with rising rates in parallel to those of obesity, type 2 diabetes, and metabolic syndrome. NAFLD encompasses a wide spectrum of pathology from simple steatosis to nonalcoholic steatohepatitis (NASH) and cirrhosis, which are linked to poor outcomes. Studies confirm a significant amount of undiagnosed NAFLD and related fibrosis within the community, increasing the overall burden of the disease. NAFLD appears to be more prevalent in certain populations, such as those with type 2 diabetes and metabolic syndrome. Early detection and lifestyle modifications, including weight loss and regular exercise, have been shown to improve outcomes. Adverse cardiovascular events are a key contributor to NAFLD-associated morbidity and mortality, and efforts to minimize their occurrence are essential. A targeted and algorithmic approach using noninvasive diagnostic techniques is promptly required to identify and risk-stratify patients with NAFLD. Patients at low risk of progression to NASH and advanced fibrosis can be managed in the primary care setting, while those at high risk of disease progression should be referred to hepatology specialists for surveillance and treatment. This review summarizes the key data of NAFLD's impact within primary care populations and proposes a potential algorithmic approach to identifying and managing such patients.

A portable single-sided magnetic-resonance sensor for the grading of liver steatosis and fibrosis

Low-cost non-invasive diagnostic tools for staging the progression of non-alcoholic chronic liver failure from fatty liver disease to steatohepatitis are unavailable. Here, we describe the development and performance of a portable single-sided magnetic-resonance sensor for grading liver steatosis and fibrosis using diffusion-weighted multicomponent T2 relaxometry. In a diet-induced mouse model of non-alcoholic fatty liver disease, the sensor achieved overall accuracies of 92% (Cohen's kappa, κ = 0.89) and 86% (κ = 0.78) in the ex vivo grading of steatosis and fibrosis, respectively. Localization of the measurements in living mice through frequency-dependent spatial encoding led to an overall accuracy of 87% (κ = 0.81) for the grading of steatosis. In human liver samples, the sensor graded steatosis with an overall accuracy of 93% (κ = 0.88). The use of T2 relaxometry as a sensitive measure in fully automated low-cost magnetic-resonance devices at the point of care would alleviate the accessibility and cost limits of magnetic-resonance imaging for diagnosing liver disease and assessing liver health before liver transplantation.

Emerging risk factors for nonalcoholic fatty liver disease associated hepatocellular carcinoma

Worldwide, nonalcoholic fatty liver disease (NAFLD) has reached epidemic proportions and in parallel, hepatocellular carcinoma (HCC) has become one of the fastest growing cancers. Epidemiological studies have not only shed light on the prevalence and incidence of the disease but have also unmasked important environmental risk factors, including the role of diabetes and dyslipidemia in disease pathogenesis. Genetic association studies have identified single nucleotide polymorphisms implicated in NAFLD-HCC, many of which are part of lipid metabolism pathways. Through these clinical studies and subsequently, translational and basic research, the role of statins as a chemoprotective agent has also emerged with ongoing clinical trials assessing their utility in HCC prevention and treatment. In this review, we summarize the recent epidemiological studies describing the burden of NAFLD-HCC in different patient populations and countries. We discuss the genetic and environmental risk factors for NAFLD-HCC and highlight the chemoprotective role of statins and aspirin. We also summarize what is known about NAFLD-HCC in the cirrhosis and non-cirrhosis populations and briefly address the role of surveillance in NAFLD-HCC patients.

Healthcare resource utilization and costs of nonalcoholic steatohepatitis patients with advanced liver disease in Italy

BACKGROUND AND AIMS

Nonalcoholic steatohepatitis (NASH) may progress to advanced liver disease (AdvLD). This study characterized comorbidities, healthcare resource utilization (HCRU) and associated costs among hospitalized patients with AdvLD due to NASH in Italy.

METHODS AND RESULTS

Adult nonalcoholic fatty liver disease (NAFLD)/NASH patients from 2011 to 2017 were identified from administrative databases of Italian local health units using ICD-9-CM codes. Development of compensated cirrhosis (CC), decompensated cirrhosis (DCC), hepatocellular carcinoma (HCC), or liver transplant (LT) was identified using first diagnosis date for each severity cohort (index-date). Patients progressing to multiple disease stages were included in >1 cohort. Patients were followed from index-date until the earliest of disease progression, end of coverage, death, or end of study. Within each cohort, per member per month values were annualized to calculate all-cause HCRU or costs(€) in 2017. Of the 9,729 hospitalized NAFLD/NASH patients identified, 97% were without AdvLD, 1.3% had CC, 3.1% DCC, 0.8% HCC, 0.1% LT. Comorbidity burden was high across all cohorts. Mean annual number of inpatient services was greater in patients with AdvLD than without AdvLD. Similar trends were observed in outpatient visits and pharmacy fills. Mean total annual costs increased with disease severity, driven primarily by inpatient services costs.

CONCLUSION

NAFLD/NASH patients in Italy have high comorbidity burden. AdvLD patients had significantly higher costs. The higher prevalence of DCC compared to CC in this population may suggest challenges of effectively screening and identifying NAFLD/NASH patients. Early identification and effective management are needed to reduce risk of disease progression and subsequent HCRU and costs.

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.

Performance of common imaging techniques vs serum biomarkers in assessing fibrosis in patients with chronic hepatitis B: A systematic review and meta-analysis

BACKGROUND

Noninvasive biomarkers have been developed to predict hepatitis B virus (HBV) related fibrosis owing to the significant limitations of liver biopsy. Both serum biomarkers and imaging techniques have shown promising results and may improve the evaluation of liver fibrosis. However, most of the previous studies focused on the diagnostic effects of various imaging techniques on fibrosis in all chronic liver diseases.

AIM

To compare the performance of common imaging methods and serum biomarkers for prediction of significant fibrosis caused only by HBV infection.

METHODS

A systematic review was conducted on the records available in PubMed, EMBASE, and the Cochrane Library electronic databases until December 2018. We systematically assessed the effectiveness of two serum biomarkers and three imagine techniques in predicting significant fibrosis solely caused by HBV infection. The serum biomarkers included aspartate aminotransferase-to-platelet ratio index (APRI) and fibrosis index based on the 4 factors (FIB-4). The three imaging techniques included acoustic radiation force impulse (ARFI), FibroScan, and magnetic resonance elastography (MRE). Three parameters, the area under the summary receiver operating characteristic curve (AUSROC), the summary diagnostic odds ratio, and the summary sensitivity and specificity, were used to examine the accuracy of all tests for liver fibrosis.

RESULTS

Out of 2831 articles evaluated for eligibility, 204 satisfied the predetermined inclusion criteria for this current meta-analysis. Eventually, our final data contained 81 studies. The AUSROCs of serum biomarkers of APRI and FIB-4 were both 0.75. For imaging techniques (ARFI, FibroScan, and MRE), the areas were 0.89, 0.83, and 0.97, respectively. The heterogeneities of ARFI and FibroScan were statistically significant (I² > 50%). The publication bias was not observed in any of the serum biomarkers or imaging methods.

CONCLUSION

These five methods have attained an acceptable level of diagnostic accuracy. Imaging techniques, MRE in particular, demonstrate significant advantages in accurately predicting HBV-related significant fibrosis, while serum biomarkers are admissible methods.

Prospective comparison of transient, point shear wave, and magnetic resonance elastography for staging liver fibrosis

OBJECTIVES

To perform head-to-head comparisons of the feasibility and diagnostic performance of transient elastography (TE), point shear-wave elastography (pSWE), and magnetic resonance elastography (MRE).

METHODS

This prospective, cross-sectional, dual-center imaging study included 100 patients with known or suspected chronic liver disease caused by hepatitis B or C virus, nonalcoholic fatty liver disease, or autoimmune hepatitis identified between 2014 and 2018. Liver stiffness measured with the three elastographic techniques was obtained within 6 weeks of a liver biopsy. Confounding effects of inflammation and steatosis on association between fibrosis and liver stiffness were assessed. Obuchowski scores and AUCs for staging fibrosis were evaluated and the latter were compared using the DeLong method.

RESULTS

TE, pSWE, and MRE were technically feasible and reliable in 92%, 79%, and 91% subjects, respectively. At univariate analysis, liver stiffness measured by all techniques increased with fibrosis stages and inflammation and decreased with steatosis. For classification of dichotomized fibrosis stages, the AUCs were significantly higher for distinguishing stages F0 vs. ≥ F1 with MRE than with TE (0.88 vs. 0.71; p < 0.05) or pSWE (0.88 vs. 0.73; p < 0.05), and for distinguishing stages ≤ F1 vs. ≥ F2 with MRE than with TE (0.85 vs. 0.75; p < 0.05). TE, pSWE, and MRE Obuchowski scores for staging fibrosis stages were respectively 0.89 (95% CI 0.85-0.93), 0.90 (95% CI 0.85-0.94), and 0.94 (95% CI 0.91-0.96).

CONCLUSION

MRE provided a higher diagnostic performance than TE and pSWE for staging early stages of liver fibrosis.

TRIAL REGISTRATION

NCT02044523 KEY POINTS: • The technical failure rate was similar between MRE and US-based elastography techniques. • Liver stiffness measured by MRE and US-based elastography techniques increased with fibrosis stages and inflammation and decreased with steatosis. • MRE provided a diagnostic accuracy higher than US-based elastography techniques for staging of early stages of histology-determined liver fibrosis.

A Structured Literature Review of the Epidemiology and Disease Burden of Non-Alcoholic Steatohepatitis (NASH)

INTRODUCTION

Non-Alcoholic Steatohepatitis (NASH) is a chronic, progressive disease characterized by fatty liver and liver cell injury, advancing to fibrosis, cirrhosis and hepatocellular carcinoma (HCC). Diagnosis involves liver biopsy; however, as a result of its high cost and invasiveness, NASH remains underdiagnosed, and accurate burden of disease (BoD) data are lacking. Our aim was to understand the epidemiological and BoD landscape in NASH and identify knowledge gaps.

METHODS

The Ovid search engine was used to conduct a structured review, following quality systematic principles. It included publications that reported on epidemiology, quality of life (QoL) and BoD outcomes in NASH adults. Searches were limited to English language studies published between January 2007 and September 2017. Additional grey literature searches were conducted. A total of 53 references were selected; 38 were peer-reviewed and 15 were grey literature sources.

RESULTS

NASH is estimated to affect 3-5% of the global population, most suffering from several comorbidities. Advancing fibrosis drives clinical outcomes, with approximately 20% of patients developing cirrhosis and/or HCC, the latter being a leading cause of death in NASH. A recent model predicted the 15-year survival of advanced fibrosis patients at F3 and F4 as 51.0% and 28.4%, respectively. The limited data consistently show that NASH patients experience significantly poorer QoL and higher costs compared to non-NASH patients.

CONCLUSION

This first broad-ranging examination of NASH literature revealed a paucity of evidence, with poor-quality, small studies found. The overwhelming impact of NASH and its patient and healthcare burden is evident. Further evidence is needed to improve our understanding of NASH, especially as fibrosis stages advance.

FUNDING

Gilead Science Inc.

A Simple Index for Nonalcoholic Steatohepatitis-HUFA-Based on Routinely Performed Blood Tests

Background and objectives: Data suggests that nearly 30% of the general population have steatosis and up to 5% of this population develops nonalcoholic steatohepatitis (NASH). Liver biopsy is still considered to be the gold standard for the diagnosis of NASH. Great effort is being made toward the identification of sensitive diagnostic tests that do not involve invasive procedures to address a common concern in patients with the nonalcoholic fatty liver disease—whether they have NASH or simple steatosis. We aimed to investigate the independent predictors and develop a non-invasive, easy-to-perform, low-cost set of parameters that may be used in clinical practice to differentiate simple steatosis from NASH. Methods: А cross-sectional study of nonalcoholic fatty liver disease (NAFLD) patients divided into two groups: group I—simple steatosis (SS) and group II—biopsy-proven NASH. Strict inclusion criteria and stepwise analysis allowed the evaluation of a vast number of measured/estimated parameters. Results: One hundred and eleven patients were included—82 with simple steatosis and 29 with biopsy-proven NASH. The probability of NASH was the highest when homeostatic model assessment of insulin resistance (HOMA-IR) was above 2.5, uric acid above 380 µmol/L, ferritin above 100 µg/L and ALT above 45 U/L. An acronym of using first letters was created and named the HUFA index. This combined model resulted in an area under the receiver operator characteristic curve (AUROC) of 0.94, provided sensitivity, specificity, positive predictive value and a negative predictive value for NASH of 70.3%, 95.1%, 83.1% and 90.0%, respectively. Conclusion: We suggest a simple non-invasive predictive index HUFA that encompasses four easily available parameters (HOMA-IR, uric acid, ferritin and ALT) to identify patients with NASH, which may reduce the need for a liver biopsy on a routine basis in patients with NAFLD.

A cut-off value of shear wave speed to distinguish nonalcoholic steatohepatitis candidates

To distinguish and characterize nonalcoholic steatohepatitis (NASH) candidates from among medical checkup visitor diagnosed with nonalcoholic fatty liver diseases (mcNAFLDs).A cut-off value has not been established to differentiate NASH at the earliest stage in NAFLD.Shear wave speed (SWS) was measured in the livers of 480 mcNAFLDs. NASH candidates were screened out by adopting a statistically defined cut-off value of SWS and were characterized in terms of food preference.SWS ranged between 1.11 and 2.18 m/s and fit a Gaussian distribution (r = 0.98) with an average and SD of 1.324 and 0.0847 m/s, respectively, in 320/160 males/females 64.4 (interquartile range 57.3-69.4) years old. The average plus SD (1.41 m/s) screened out 82 (17.1%) NASH candidates, who were significantly older (66.8 vs. 64.1 years old, P = 0.001) and had higher fibrosis 4 index values (1.58 vs. 1.33, P < 0.0001) than the remaining mcNAFLDs. The number of patients with a BMI greater than 25 kg/m was 118 (29.6%) mcNAFLDs and 34 (41.5%) NASH candidates, with a significantly higher frequency in NASH candidates (P = 0.05). Obese patients preferentially ate fatty acids in general, while NASH candidates preferred to consume several long-chain unsaturated fatty acids irrespective of their BMI.These results suggest that NASH candidates who have a longer disease duration and pathological progression can be distinguished from mcNAFLDs by a statistically defined cut-off value of SWS. The defined value indicates that there are different food habitats associated with obesity and NAFLD progression.

A cut-off value of shear wave speed to distinguish nonalcoholic steatohepatitis candidates

To distinguish and characterize nonalcoholic steatohepatitis (NASH) candidates from among medical checkup visitor diagnosed with nonalcoholic fatty liver diseases (mcNAFLDs).A cut-off value has not been established to differentiate NASH at the earliest stage in NAFLD.Shear wave speed (SWS) was measured in the livers of 480 mcNAFLDs. NASH candidates were screened out by adopting a statistically defined cut-off value of SWS and were characterized in terms of food preference.SWS ranged between 1.11 and 2.18 m/s and fit a Gaussian distribution (r = 0.98) with an average and SD of 1.324 and 0.0847 m/s, respectively, in 320/160 males/females 64.4 (interquartile range 57.3-69.4) years old. The average plus SD (1.41 m/s) screened out 82 (17.1%) NASH candidates, who were significantly older (66.8 vs. 64.1 years old, P = 0.001) and had higher fibrosis 4 index values (1.58 vs. 1.33, P < 0.0001) than the remaining mcNAFLDs. The number of patients with a BMI greater than 25 kg/m was 118 (29.6%) mcNAFLDs and 34 (41.5%) NASH candidates, with a significantly higher frequency in NASH candidates (P = 0.05). Obese patients preferentially ate fatty acids in general, while NASH candidates preferred to consume several long-chain unsaturated fatty acids irrespective of their BMI.These results suggest that NASH candidates who have a longer disease duration and pathological progression can be distinguished from mcNAFLDs by a statistically defined cut-off value of SWS. The defined value indicates that there are different food habitats associated with obesity and NAFLD progression.

Health and economic benefits of reducing sugar intake in the USA, including effects via non-alcoholic fatty liver disease: a microsimulation model

OBJECTIVES

Excessive consumption of added sugars in the human diet has been associated with obesity, type 2 diabetes (T2D), coronary heart disease (CHD) and other elements of the metabolic syndrome. Recent studies have shown that non-alcoholic fatty liver disease (NAFLD) is a critical pathway to metabolic syndrome. This model assesses the health and economic benefits of interventions aimed at reducing intake of added sugars.

METHODS

Using data from US National Health Surveys and current literature, we simulated an open cohort, for the period 2015-2035. We constructed a microsimulation model with Markov chains for NAFLD (including steatosis, non-alcoholic steatohepatitis (NASH), cirrhosis and hepatocellular carcinoma (HCC)), body mass index, T2D and CHD. We assessed reductions in population disease prevalence, disease-attributable disability-adjusted life years (DALYs) and costs, with interventions that reduce added sugars consumption by either 20% or 50%.

FINDINGS

The model estimated that a 20% reduction in added sugars intake will reduce prevalence of hepatic steatosis, NASH, cirrhosis, HCC, obesity, T2D and CHD. Incidence of T2D and CHD would be expected to decrease by 19.9 (95% CI 12.8 to 27.0) and 9.4 (95% CI 3.1 to 15.8) cases per 100 000 people after 20 years, respectively. A 20% reduction in consumption is also projected to annually avert 0.767 million (M) DALYs (95% CI 0.757M to 0.777M) and a total of US$10.3 billion (B) (95% CI 10.2B to 10.4B) in discounted direct medical costs by 2035. These effects increased proportionally when added sugars intake were reduced by 50%.

CONCLUSIONS

The decrease in incidence and prevalence of disease is similar to results in other models, but averted costs and DALYs were higher, mainly due to inclusion of NAFLD and CHD. The model suggests that efforts to reduce consumption of added sugars may result in significant public health and economic benefits.

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

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

CONCLUSIONS

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

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

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

Detection of Steatohepatitis in a Rat Model by Using Spectroscopic Shear-Wave US Elastography

Purpose To compare low- versus high-frequency ultrasonographic (US) elastography for detection of steatohepatitis in rats by using histopathologic findings as the reference standard. Materials and Methods Between March and September 2014, after receiving approval from the institutional animal care committee, 60 male Sprague-Dawley rats were fed either a standard chow for 4 weeks or a methionine- and choline-deficient diet for 1, 4, 8, or 12 weeks to induce a continuum of steatohepatitis severity. Liver shear stiffness was assessed in vivo by using US elastography at low (40-130-Hz) and high (130-220-Hz) frequencies. Histologic features (steatosis, inflammation, and fibrosis) and modified nonalcoholic steatohepatitis categories were used as reference standards. Definite steatohepatitis was divided into steatohepatitis with fibrosis stage 1 or lower and stage 2 and higher. Analyses included the Kendall τ correlation, multivariable linear regression analyses, Kruskal-Wallis rank sum test, and post hoc Dunn test with Holm correction. Results Correlations between liver shear stiffness and histologic features were higher at high frequencies than at low frequencies (low frequency: 0.08, 0.24, and 0.20 for steatosis, inflammation, and fibrosis, respectively; high frequency: 0.11, 0.35, and 0.50, respectively). The absolute value of multivariable regression coefficients was higher at high frequencies for the presence of steatosis, inflammation grade, and fibrosis stage (low frequency: -0.475, 0.157, and 0.209, respectively; high frequency: -0.893, 0.357, and 0.447, respectively). The model fit was better at high frequencies (adjusted R2 = 0.57) than at low frequencies (adjusted R2 = 0.21). There was a significant difference between steatohepatitis categories at both low and high frequencies (P = .022 and P < .001, respectively). Conclusion Liver shear stiffness measured with US elastography provided better distinction of steatohepatitis categories at high frequencies than at low frequencies. Further, liver shear stiffness decreased with steatosis and increased with inflammation and fibrosis at both low and high frequencies. © RSNA, 2016 Online supplemental material is available for this article.

Liver fibrosis: Review of current imaging and MRI quantification techniques

Liver fibrosis is characterized by the accumulation of extracellular matrix proteins such as collagen in the liver interstitial space. All causes of chronic liver disease may lead to fibrosis and cirrhosis. The severity of liver fibrosis influences the decision to treat or the need to monitor hepatic or extrahepatic complications. The traditional reference standard for diagnosis of liver fibrosis is liver biopsy. However, this technique is invasive, associated with a risk of sampling error, and has low patient acceptance. Imaging techniques offer the potential for noninvasive diagnosis, staging, and monitoring of liver fibrosis. Recently, several of these have been implemented on ultrasound (US), computed tomography, or magnetic resonance imaging (MRI). Techniques that assess changes in liver morphology, texture, or perfusion that accompany liver fibrosis have been implemented on all three imaging modalities. Elastography, which measures changes in mechanical properties associated with liver fibrosis-such as strain, stiffness, or viscoelasticity-is available on US and MRI. Some techniques assessing liver shear stiffness have been adopted clinically, whereas others assessing strain or viscoelasticity remain investigational. Further, some techniques are only available on MRI-such as spin-lattice relaxation time in the rotating frame (T₁ ρ), diffusion of water molecules, and hepatocellular function based on the uptake of a liver-specific contrast agent-remain investigational in the setting of liver fibrosis staging. In this review, we summarize the key concepts, advantages and limitations, and diagnostic performance of each technique. The use of multiparametric MRI techniques offers the potential for comprehensive assessment of chronic liver disease severity.

LEVEL OF EVIDENCE

5 J. MAGN. RESON. IMAGING 2017;45:1276-1295.

Current complications and challenges in nonalcoholic steatohepatitis screening and diagnosis

Nonalcoholic steatohepatitis (NASH) can lead to complications such as liver failure, cirrhosis and hepatocellular carcinoma. The diagnostic gold standard for NASH is liver biopsy; however, other noninvasive methods have been developed. In this article, the authors evaluate current methods in NASH screening and diagnosis. Routine radiologic modalities were found to detect hepatic steatosis accurately, but were unable to establish the diagnosis of NASH or stage of fibrosis. Newly developed elastography based techniques seem promising to estimate liver fibrosis. Other noninvasive tests such as FibroTest, ELF, Hepascore, FIB-4, NFS, FLI and ION (biochemical panels) have AUROCs ranging between 0.80-0.98 for detecting advanced fibrosis but lack specificity for detecting mild fibrosis. Noninvasive tools, especially elastography, identify NASH associated advanced fibrosis potentially reducing liver biopsies. More research is needed to validate the clinical utility of these tests.

Non-alcoholic fatty liver disease and cardiovascular risk: Pathophysiological mechanisms and implications

Non-alcoholic fatty liver disease (NAFLD) has become one of the most frequent chronic liver diseases in the Western society and its prevalence is likely to rise even further. An increasing body of evidence shows that NAFLD is not only a potentially progressive liver disease, but also has systemic consequences. More specifically, evidence points out that NAFLD has to be considered as a significant independent risk factor for subclinical and clinical cardiovascular disease (CVD). Long-term follow-up studies demonstrate cardiovascular mortality to be the most important cause of death in NAFLD patients. Moreover, ample evidence associates NAFLD with endothelial dysfunction, increased pulse wave velocity, increased coronary arterial calcifications and increased carotid intima media thickness, all established markers for CVD. Despite of all this evidence, the mechanisms by which NAFLD causally contributes to CVD are not fully elucidated. Furthermore, an extensive overview of all potential pathophysiological mechanisms and the corresponding current data are lacking. In this review we summarise current knowledge, originating from fundamental and clinical research, that mechanistically links NAFLD to CVD. Subsequently, the impact of CVD on current clinical practice and future research in the area of NALFD are discussed.

Formulation for Effective Screening and Management of Nonalcoholic Steatohepatitis: Noninvasive NAFLD Management Strategy

To establish a versatile means for screening and management of nonalcoholic steatohepatitis (NASH), shear wave velocity was measured in 20 normal controls and 138 consecutive nonalcoholic fatty liver disease (NAFLD) cases. Referencing biochemical properties in 679 healthy volunteers, a formula to distinguish NASH suspects was established and validated in another cohort of 138 histologically proven NAFLD cases. NASH and simple steatosis (SS) suspects were selected based on a plot of shear wave velocity against age. A formula consisting of five factors (γ-glutamyl transpeptidase, alkaline phosphatase, platelet counts, body mass index, and presence/absence of type 2 diabetes mellitus) distinguished NASH suspects from SS suspects with area under the receiver operating characteristic curve values of 86% and 84% in the development and validation cohorts. Among 25 NAFLD cases in which shear wave velocity was repeatedly measured, 8 and 9 cases revealed an increase or decrease, respectively, of shear wave velocity in the entire liver, and the corresponding change in shear wave velocity was primarily observed in the right lobe or the left lateral segment, respectively. These results suggest that the new formula and sequential shear wave velocity measurements at each segment enable high throughput screening of NASH suspects and noninvasive assessment of pathophysiological alleviation/aggravation in cases of NASH.

Nonalcoholic Fatty Liver Disease for Identification of Preclinical Carotid Atherosclerosis

Nonalcoholic fatty liver disease (NAFLD) is associated with cardiovascular disease, yet whether identification of NAFLD in asymptomatic individuals is helpful over established risk factors remains unknown. A total of 37,799 asymptomatic adults aged 20 years or older who underwent comprehensive health check-up examination, including abdominal and carotid artery duplex ultrasonography (US) were included in the analysis. Nonalcoholic fatty liver disease was diagnosed with US and exclusion of secondary causes of fat accumulation or other causes of chronic liver disease, and graded as mild or moderate to severe fatty liver. Individuals with carotid plaque identified on carotid artery US were considered at risk for cardiovascular disease. Metabolic syndrome (MetS) was defined by the adult treatment panel III criteria. Nonalcoholic fatty liver disease was an independent factor associated with carotid plaque in a dose-dependent manner (odds ratio [OR]; 95% confidence interval [CI]: 1.09 [1.03-1.16] and 1.13 [1.06-1.21] for mild and ≥ moderate degree of NAFLD). Among clinically-relevant subgroups, NAFLD was more closely associated with carotid plaque in young adults (aged < 60 years) without MetS (OR [95% CI]: 1.13 [1.03-1.19] and 1.16 [1.06-1.27] for mild and ≥ moderate degree of NAFLD) than old adults (aged ≥ 60 years) or with MetS (OR [95% CI]: 1.06 [0.97-1.17] and 1.07 [0.97-1.19] for mild and ≥ moderate degree NAFLD). In young adults without MetS, the prevalence of carotid plaques was 32.8% and the sensitivity and specificity of NAFLD for carotid plaque was 0.38 and 0.67, respectively. In conclusion, NAFLD is associated with carotid plaque independent of traditional risk factors, especially in young adults without MetS. Nonalcoholic fatty liver disease could help identify additional individuals with preclinical atherosclerosis in asymptomatic young adults without MetS, yet, showed suboptimal performance as a screening tool.