A comparison of FibroMeter™ NAFLD Score, NAFLD fibrosis score, and transient elastography as noninvasive diagnostic tools for hepatic fibrosis in patients with biopsy-proven non-alcoholic fatty liver disease

Non-invasive prediction nomogram for predicting significant fibrosis in patients with metabolic-associated fatty liver disease: a cross-sectional study

BACKGROUND AND AIM

This study aims to validate the efficacy of the conventional non-invasive score in predicting significant fibrosis in metabolic-associated fatty liver disease (MAFLD) and to develop a non-invasive prediction model for MAFLD.

METHODS

This cross-sectional study was conducted among 7701 participants with MAFLD from August 2018 to December 2023. All participants were divided into a training cohort and a validation cohort. The study compared different subgroups' demographic, anthropometric, and laboratory examination indicators and conducted logistic regression analysis to assess the correlation between independent variables and liver fibrosis. Nomograms were created using the logistic regression model. The predictive values of noninvasive models and nomograms were evaluated using receiver operating characteristic (ROC) curve analysis and decision curve analysis (DCA).

RESULTS

Four nomograms were developed for the quantitative analysis of significant liver fibrosis risk based on the multivariate logistic regression analysis results. The nomogram's area under ROC curves (AUC) was 0.710, 0.714, 0.748, and 0.715 in overall MAFLD, OW-MAFLD, Lean-MAFLD, and T2DM-MAFLD, respectively. The nomogram had a higher AUC in all MAFLD participants and OW-MAFLD than the other non-invasive scores. The DCA curve showed that the net benefit of each nomogram was higher than that of APRI and FIB-4. In the validation cohort, the AUCs of the nomograms were 0.722, 0.750, 0.719, and 0.705, respectively.

CONCLUSION

APRI, FIB-4, and NFS performed poorly predicting significant fibrosis in patients with MAFLD. The new model demonstrated improved diagnostic accuracy and clinical applicability in identifying significant fibrosis in MAFLD.

The association of triglyceride-glucose-waist circumference with metabolic associated fatty liver disease and the severity of liver steatosis and fibrosis in American adults: a population-based study

BACKGROUND

The global obesity pandemic has led to an alarming rise in the prevalence of metabolic-associated fatty liver disease (MAFLD), making it a substantial clinical and economic burden on society. Early detection and effective treatment of MAFLD are imperative to mitigate its impact.

METHODS

This cross-sectional study was conducted involving 4634 adults from the National Health and Nutrition Examination Surveys (NHANES) 2017-2018 cycle. Transient elastography (TE) was used to diagnose MAFLD and assess the extent of liver steatosis and fibrosis. Multivariate logistic regression models were utilized to examine the association between the triglyceride and glucose index-waist circumference (TyG-WC) and the risk of MAFLD, liver fibrosis, and steatosis.

RESULTS

A positive association between TyG-WC and MAFLD persisted across all three models: model1: OR = 8.44, 95% CI: 6.85-10.38 (unadjusted), model2: OR = 8.28, 95% CI: 6.53-10.50 (partially adjusted), and model3: OR = 7.98, 95% CI: 4.11-15.46 (fully adjusted). Further investigation through interaction and stratified analysis revealed that this association was more pronounced in the non-obese and Non-Hispanic White persons groups. Moreover, a non-linear relationship analysis unveiled threshold and saturation effects between TyG-WC and MAFLD. Specifically, a TyG-WC value of approximately 600 may represent the threshold effect for MAFLD risk, while 1200 may signify the saturation effect of MAFLD risk. Finally, a robust correlation between TyG-WC and the severity of liver steatosis and fibrosis was found.

CONCLUSIONS

The findings suggest that the TyG-WC index exhibits excellent predictive value for MAFLD in the general American population.

Accuracy of prognostic serological biomarkers in predicting liver fibrosis severity in people with metabolic dysfunction-associated steatotic liver disease: a meta-analysis of over 40,000 participants

Introduction

A prognostic model to predict liver severity in people with metabolic dysfunction-associated steatotic liver disease (MASLD) is very important, but the accuracy of the most commonly used tools is not yet well established.

Objective

The meta-analysis aimed to assess the accuracy of different prognostic serological biomarkers in predicting liver fibrosis severity in people with MASLD.

Methods

Adults ≥18 years of age with MASLD were included, with the following: liver biopsy and aspartate aminotransferase-to-platelet ratio (APRI), fibrosis index-4 (FIB-4), non-alcoholic fatty liver disease fibrosis score (NFS), body mass index, aspartate aminotransferase/alanine aminotransferase ratio, diabetes score (BARD score), FibroMeter, FibroTest, enhanced liver fibrosis (ELF), Forns score, and Hepascore. Meta-analyses were performed using a random effects model based on the DerSimonian and Laird methods. The study's risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2.

Results

In total, 138 articles were included, of which 86 studies with 46,514 participants met the criteria for the meta-analysis. The results for the summary area under the receiver operating characteristic (sAUROC) curve, according to the prognostic models, were as follows: APRI: advanced fibrosis (AF): 0.78, any fibrosis (AnF): 0.76, significant fibrosis (SF): 0.76, cirrhosis: 0.72; FIB-4: cirrhosis: 0.83, AF: 0.81, AnF: 0.77, SF: 0.75; NFS: SF: 0.81, AF: 0.81, AnF: 0.71, cirrhosis: 0.69; BARD score: SF: 0.77, AF: 0.73; FibroMeter: SF: 0.88, AF: 0.84; FibroTest: SF: 0.86, AF: 0.78; and ELF: AF: 0.87.

Conclusion

The results of this meta-analysis suggest that, when comparing the scores of serological biomarkers with liver biopsies, the following models showed better diagnostic accuracy in predicting liver fibrosis severity in people with MASLD: FIB-4 for any fibrosis, FibroMeter for significant fibrosis, ELF for advanced fibrosis, and FIB-4 for cirrhosis.Clinical trial registration: [https://clinicaltrials.gov/], identifier [CRD 42020180525].

Association of serum uric acid-to-high-density lipoprotein cholesterol ratio with non-alcoholic fatty liver disease in American adults: a population-based analysis

Objective

Non-invasive disease indicators are currently limited and need further research due to the increased non-alcoholic fatty liver disease (NAFLD) prevalence worldwide. The serum uric acid-to-high-density lipoprotein cholesterol ratio (UHR) has been recognized as a novel inflammatory and metabolic marker. Herein, we explored the correlation between UHR and the risk of NAFLD in-depth.

Methods

A total of 3,766 participants were included in our survey, and the National Health and Nutrition Examination Survey (NHANES) 2017-2018 cycle provided the cross-sectional study population. Weighted multivariable logistic regression and multivariate linear regression analyses were performed to assess the association between the UHR and the odds of NAFLD and liver steatosis and fibrosis severity, respectively. Moreover, we explored the non-linear relationship between the UHR and NAFLD by the generalized additive model.

Results

NAFLD probabilities were statistically demonstrated to be positively correlated with the UHR (OR = 1.331 per SD increase, 95% CI: 1.100, 1.611). The positive connection of the UHR with NAFLD risk persisted significantly in female subjects but not in male subjects in subgroup analyses stratified by gender. The non-linear relationship analysis demonstrated that a UHR between ~20 and 30% suggested a saturation effect of NAFLD risk. Furthermore, a dramatically positive correlation was found between the UHR and hepatic steatosis severity but not fibrosis. Finally, the receiver operating characteristic analysis suggested that UHR had a better predictive value for NAFLD than either serum uric acid (sUA) or high-density lipoprotein cholesterol (HDL) alone [UHR (area under curve): 0.6910; 95% CI: 0.6737-0.7083; P < 0.0001].

Conclusion

Our investigation revealed that the elevated UHR level was independently related to an increased NAFLD risk and the severity of liver steatosis in American individuals. The correlation differed according to sex. This non-invasive indicator may enhance the capacity to predict the onset of NAFLD and may uncover alternative therapeutic interventional targets.

Ideal Cardiovascular Health Metrics Are Associated with Reduced Severity of Hepatic Steatosis and Liver Fibrosis Detected by Transient Elastography

Life's Simple 7 (LS7) is the American Heart Association's (AHA) proposal for a healthy lifestyle, also known as cardiovascular health (CVH) metrics. However, the association between CVH metrics and the severity of hepatic steatosis and liver fibrosis detected by transient elastography is unknown. We performed a cross-sectional study using the data from the 2017-2018 National Health and Nutrition Examination Survey (NHANES) cycle. The controlled attenuation parameter (CAP) and liver stiffness measurement (LSM) were used to evaluate the severity of hepatic steatosis and liver fibrosis and to define NAFLD, advanced liver fibrosis, and cirrhosis. A total of 2679 participants were included. Multivariate linear regression analysis revealed that per 1-unit increase in the CVH metric, CAP and LSM decreased by 8.565 units and 0.274 units, respectively. In the multivariate logistic regression analysis, the risk of NAFLD, advanced liver fibrosis, and cirrhosis were 7, 10, and 6 times higher in the poor CVH group than in the ideal CVH group. Subgroup analysis indicated that CVD patients and non-Hispanic whites could benefit more from ideal CVH. In conclusion, adherence to ideal CVH metrics, as proposed by the AHA, can significantly reduce the risk of hepatic steatosis and liver fibrosis.

Non-invasive methods to evaluate liver fibrosis in patients with non-alcoholic fatty liver disease

Non-alcoholic Fatty Liver Disease (NAFLD) is a chronic liver disease that is strongly related to insulin resistance and metabolic syndrome, and it has become the most common liver disorder in developed countries. NAFLD embraces the full pathological process of three conditions: steatosis, non-alcoholic steatohepatitis, and finally, cirrhosis. As NAFLD progresses, symptoms will become increasingly severe as fibrosis develops. Therefore, evaluating the fibrosis stage is crucial for patients with NAFLD. A liver biopsy is currently considered the gold standard for staging fibrosis. However, due to the limitations of liver biopsy, non-invasive alternatives were extensively studied and validated in patients with NAFLD. The advantages of non-invasive methods include their high safety and convenience compared with other invasive approaches. This review introduces the non-invasive methods, summarizes their benefits and limitations, and assesses their diagnostic performance for NAFLD-induced fibrosis.

Association of liver fibrosis biomarkers with overall and CVD mortality in the Korean population: The Dong-gu study

This study evaluated the associations of liver fibrosis biomarkers [non-alcoholic fatty liver disease fibrosis score (NFS), fibrosis-4 (FIB-4), aspartate aminotransferase/platelet ratio index (APRI), and BARD score] with mortality in Korean adults aged ≥50 years. We analyzed 7,702 subjects who participated in Dong-gu Study. The associations of liber fibrosis biomarkers with mortality were investigated using Cox proportional hazards models. Overall mortality increased with increasing NFS level [adjusted hazard ratio (aHR) 4.3, 95% confidence interval (CI) 3.3-5.5 for high risk vs. low risk], increasing FIB-4 level (aHR 3.5, 95% CI 2.9-4.4 for high risk vs. low risk), and increasing APRI level (aHR 3.5, 95% CI 2.1-5.8 for high risk vs. low risk) but not with BARD score. The Harrell's concordance index for overall mortality for the NFS and FIB-4 was greater than that for the APRI and BARD score. In conclusion, NFS, FIB-4, and APRI showed a significant relationship with the overall mortality, and NFS and FIB-4 showed a significant relationship with the CVD mortality after adjustment for covariates. In addition, the NFS and FIB-4 were more predictive of overall mortality than the APRI and BARD score in Korean adults aged ≥50 years.

Nonalcoholic fatty liver disease and obesity: An Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) 2022

Background

This Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) provides clinicians an overview of nonalcoholic fatty liver disease (NAFLD), potential progression to nonalcoholic steatohepatitis (NASH), and their application to obesity.

Methods

The scientific information for this CPS is based upon published scientific citations, clinical perspectives of OMA authors, and peer review by the Obesity Medicine Association leadership.

Results

Topics of this CPS include the prevalence of NAFLD and NASH, the prevalence of NAFLD and NASH among patients with obesity, as well as NAFLD and NASH definitions, diagnosis, imaging, pathophysiology, differential diagnosis, role of high fructose corn syrup and other simple sugars, and treatment (e.g., nutrition, physical activity, medications).

Conclusions

This Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) regarding NAFLD and obesity is one of a series of OMA CPSs designed to assist clinicians in the care of patients with the disease of obesity. Patients with obesity are at increased risk for NAFLD and NASH. Patients may benefit when clinicians who manage obesity understand the etiology, diagnosis, and optimal treatment of NAFLD with a goal to prevent NASH.

Accuracy of controlled attenuation parameter (CAP) and liver stiffness measurement (LSM) for assessing steatosis and fibrosis in non-alcoholic fatty liver disease: A systematic review and meta-analysis

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disease, and among the non-invasive tests, controlled attenuation parameter (CAP) and liver stiffness measurement (LSM) have shown better diagnostic performance in NAFLD. This meta-analysis aimed to evaluate the performance of CAP and LSM for assessing steatosis and fibrosis in NAFLD.

METHODS

We searched the PubMed, Web of Science, Cochrane Library, and Embase databases for relevant articles published up to February 13^th, 2022, and selected studies that met the inclusion and exclusion criteria, and evaluated the quality of evidence. Then we pooled sensitivity (SE), specificity (SP), and area under receiver operating characteristic (AUROC) curves. A random effect model was applied regardless of heterogeneity. Meta-regression analysis and subgroup analysis were performed to explore heterogeneity, and Fagan plot analysis was used to evaluate clinical utility. This meta-analysis was completed in Nanjing, Jiangsu and registered on PROSPERO (CRD42022309965).

FINDINGS

A total of 10537 patients from 61 studies were included in our meta-analysis. The AUROC of CAP were 0·924, 0·794 and 0·778 for steatosis grades ≥ S1, ≥ S2 and = S3, respectively, and the AUROC of LSM for detecting fibrosis stages ≥ F1, ≥ F2, ≥ F3, and = F4 were 0·851, 0·830, 0·897 and 0·925, respectively. Subgroup analysis revealed that BMI ≥ 30 kg/m² had lower accuracy for diagnosing S ≥ S1, ≥ S2 than BMI<30 kg/m². For the mean cut-off values, significant differences were found in CAP values among different body mass index (BMI) populations and LSM values among different regions. For diagnosing S ≥ S1, ≥ S2 and = S3, the mean CAP cut-off values for BMI ≥ 30 kg/m² were 30·7, 28·2, and 27·9 dB/m higher than for BMI < 30 kg/m² (P = 0·001, 0·001 and 0·018, respectively). For diagnosing F ≥ F2 and = F4, the mean cut-off values of Europe and America were 0·96 and 2·03 kPa higher than Asia (P = 0·027, P = 0·034), respectively. In addition, the results did not change significantly after sensitivity analysis and the trim and fill method to correct for publication bias, proving that the conclusions are robust.

INTERPRETATION

The good performance of CAP and LSM for the diagnosis of mild steatosis (S ≥ S1), advanced liver fibrosis (F ≥ F3), and cirrhosis (F = F4) can be used to screen for NAFLD in high-risk populations. Of note, the accuracy of CAP for the detection of steatosis in patients with obesity is reduced and requires specific diagnostic values. For LSM, the same diagnostic values can be used when the appropriate probes are selected based on BMI and the automated probe selection tool. The performance of CAP and LSM in assessing steatosis in patients with obesity, moderate to severe steatosis, and low-grade fibrosis should be further validated and improved in the future.

FUNDING

The study was funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD).

Association of glycated hemoglobin with non-alcoholic fatty liver disease patients and the severity of liver steatosis and fibrosis measured by transient elastography in adults without diabetes

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a well-known independent risk factor for non-alcoholic fatty liver disease (NAFLD). However, research exploring the association between blood glucose management and the risk of NAFLD status in subjects without diabetes was insufficient. This study aimed to explore the association of glycated hemoglobin (HbA1c) with NAFLD status and the severity of liver steatosis and fibrosis in non-diabetic people.

METHODS

A cross-sectional analysis was conducted on 2998 non-diabetic American adults using data from the National Health and Nutrition Examination Survey (NHANES) 2017-2018 cycle. We used multivariable logistic regression models to evaluate the association between HbA1c and NAFLD status and the severity of liver steatosis and fibrosis. Interaction and stratified analyses were additionally performed.

RESULTS

The multivariate regression analyses showed that HbA1c was associated independently with NAFLD status in all the models (model1: OR = 2.834, 95%CI: 2.321, 3.461; model 2: OR = 2.900, 95%CI: 2.312, 3.637 and model 3: OR = 1.664, 95%CI: 1.284, 2.156). We further performed the interaction and stratified analyses and discovered a significant interaction between HbA1c and BMI (P_interaction < 0.05). Finally, a robust link was shown between HbA1c level and the severity of liver steatosis, which was mainly significant in the prediabetes group, while the correlation was not significant in HbA1c level and severity of liver fibrosis after controlling for all the potential confounders.

CONCLUSIONS

We concluded that HbA1c level was positively correlated to the risk of developing NAFLD in a large non-diabetic American population. Moreover, HbA1c level was associated with the severity of liver steatosis in subjects with prediabetes, suggesting that routine screening for HbA1c among individuals with prediabetes is necessary.

Diagnostic accuracy of non-invasive tests for advanced fibrosis in patients with NAFLD: an individual patient data meta-analysis

OBJECTIVE

Liver biopsy is still needed for fibrosis staging in many patients with non-alcoholic fatty liver disease. The aims of this study were to evaluate the individual diagnostic performance of liver stiffness measurement by vibration controlled transient elastography (LSM-VCTE), Fibrosis-4 Index (FIB-4) and NAFLD (non-alcoholic fatty liver disease) Fibrosis Score (NFS) and to derive diagnostic strategies that could reduce the need for liver biopsies.

DESIGN

Individual patient data meta-analysis of studies evaluating LSM-VCTE against liver histology was conducted. FIB-4 and NFS were computed where possible. Sensitivity, specificity and area under the receiver operating curve (AUROC) were calculated. Biomarkers were assessed individually and in sequential combinations.

RESULTS

Data were included from 37 primary studies (n=5735; 45% women; median age: 54 years; median body mass index: 30 kg/m²; 33% had type 2 diabetes; 30% had advanced fibrosis). AUROCs of individual LSM-VCTE, FIB-4 and NFS for advanced fibrosis were 0.85, 0.76 and 0.73. Sequential combination of FIB-4 cut-offs (<1.3; ≥2.67) followed by LSM-VCTE cut-offs (<8.0; ≥10.0 kPa) to rule-in or rule-out advanced fibrosis had sensitivity and specificity (95% CI) of 66% (63-68) and 86% (84-87) with 33% needing a biopsy to establish a final diagnosis. FIB-4 cut-offs (<1.3; ≥3.48) followed by LSM cut-offs (<8.0; ≥20.0 kPa) to rule out advanced fibrosis or rule in cirrhosis had a sensitivity of 38% (37-39) and specificity of 90% (89-91) with 19% needing biopsy.

CONCLUSION

Sequential combinations of markers with a lower cut-off to rule-out advanced fibrosis and a higher cut-off to rule-in cirrhosis can reduce the need for liver biopsies.

A sequential approach using the age-adjusted fibrosis-4 index and vibration-controlled transient elastography to detect advanced fibrosis in Korean patients with non-alcoholic fatty liver disease

BACKGROUND AND AIMS

Vibration-controlled transient elastography (VCTE) has shown good diagnostic performance in predicting fibrosis stages in patients with non-alcoholic fatty liver disease (NAFLD). However, an optimal diagnostic approach to detect advanced fibrosis in patients with NAFLD has not been established.

APPROACH AND RESULTS

We prospectively collected data from 539 subjects who underwent liver biopsy at a single centre between January 2014 and December 2019. Diagnostic performance was estimated using the area under the receiver-operating characteristic curve (AUROC). Several models combining the fibrosis 4 index (FIB-4) score and liver stiffness measurement (LSM) were analysed to reduce the need for unnecessary liver biopsies. We observed significant fibrosis (≥F2), advanced fibrosis (≥F3) and cirrhosis (F4) in 173 (32.1%), 74 (13.7%) and 46 subjects (8.5%), respectively. The AUROCs (95% CI) for LSMs to diagnose ≥F2, ≥F3 and F4 were 0.82 (0.78-0.85), 0.92 (0.89-0.94) and 0.95 (0.93-0.97), respectively. Optimal LSM cut-off values were 6.7 (≥F2), 8.3 (≥F3) and 9.8 (F4) kPa. LSMs were affected by waist circumference, serum albumin and fibrosis stage (R²  = 0.315). Abdominal obesity, elevated transaminase, diabetes mellitus and high IQR/Median were associated with the discordance of ≥2 fibrosis stages between LSMs and histologic data. The sequential use of the age-adjusted FIB-4 and LSMs yielded the least uncertainty (5.3%) in classifying disease severity with the highest diagnostic accuracy (81%) among a variety of non-invasive test combinations.

CONCLUSIONS

The sequential approach of age-adjusted FIB-4 and VCTE could represent a practical diagnostic strategy to detect advanced fibrosis in NAFLD (ClinicalTrials.gov #NCT02206841).

Epidemiology, natural history, and diagnosis of metabolic dysfunction-associated fatty liver disease: a comparative review with nonalcoholic fatty liver disease

Metabolic (dysfunction)-associated fatty liver disease (MAFLD) is the most common chronic liver disease worldwide - with an estimated global prevalence of 37%. Different from nonalcoholic fatty liver disease (NAFLD), which is an exclusion diagnosis, MAFLD is defined by a set of positive criteria. This recent change in terminology is challenging because MAFLD and NAFLD denote two similar, albeit not identical, clinical populations. When the diagnostic criteria for MAFLD are applied, liver histology appears more severe and clinical outcomes are less favorable. However, the clinical management of MAFLD and NAFLD remains similar. While liver biopsy is still the reference standard for achieving a final diagnosis, noninvasive imaging- or biomarker-based diagnostic modalities are currently gaining momentum. However, liver biopsy should be recommended when diagnostic challenges exist. In this review, we compared the epidemiology, natural history, and diagnosis of MAFLD with respect to the traditional NAFLD definition.

Macro- and micronutrients in metabolic (dysfunction) associated fatty liver disease: association between advanced fibrosis and high dietary intake of cholesterol/saturated fatty acids

BACKGROUND AND AIM

There is still no approved pharmacotherapy for metabolic (dysfunction) associated fatty liver disease (MAFLD). Although dietary and lifestyle modifications for weight loss remain the mainstay for disease management, the association between macro- and micronutrients and fibrosis stage in patients with MAFLD remains unclear. This study was undertaken to address this issue.

METHODS

This is a retrospective analysis of prospectively collected data from patients in whom MAFLD was diagnosed with vibration controlled transient elastography. Steatosis was defined by a controlled attenuation parameter ≥238 dB/m, whereas a liver stiffness measurement ≥11 kPa was considered to indicate advanced fibrosis.

RESULTS

The study sample consisted of 106 patients with MAFLD (mean age 49 ± 10 years, 52 men and 54 women). Among the different micro- and macronutrients tested, only the dietary intake of cholesterol and saturated fatty acid (SFA) was independently associated with the presence of advanced fibrosis.

CONCLUSION

Our findings suggest that cholesterol/SFA-restricted dietary regimens - as exemplified by the traditional Mediterranean diet - may reduce the risk of advanced fibrosis in patients with MAFLD.

Diagnostic accuracy of elastography and magnetic resonance imaging in patients with NAFLD: A systematic review and meta-analysis

BACKGROUND AND AIMS

Vibration-controlled transient elastography (VCTE), point shear wave elastography (pSWE), 2-dimensional shear wave elastography (2DSWE), magnetic resonance elastography (MRE), and magnetic resonance imaging (MRI) have been proposed as non-invasive tests for patients with non-alcoholic fatty liver disease (NAFLD). This study evaluated their diagnostic accuracy for liver fibrosis and non-alcoholic steatohepatitis (NASH).

METHODS

PubMED/MEDLINE, EMBASE and the Cochrane Library were searched for studies examining the diagnostic accuracy of these index tests, against histology as the reference standard, in adult patients with NAFLD. Two authors independently screened and assessed methodological quality of studies and extracted data. Summary estimates of sensitivity, specificity and area under the curve (sAUC) were calculated for fibrosis stages and NASH, using a random effects bivariate logit-normal model.

RESULTS

We included 82 studies (14,609 patients). Meta-analysis for diagnosing fibrosis stages was possible in 53 VCTE, 11 MRE, 12 pSWE and 4 2DSWE studies, and for diagnosing NASH in 4 MRE studies. sAUC for diagnosis of significant fibrosis were: 0.83 for VCTE, 0.91 for MRE, 0.86 for pSWE and 0.75 for 2DSWE. sAUC for diagnosis of advanced fibrosis were: 0.85 for VCTE, 0.92 for MRE, 0.89 for pSWE and 0.72 for 2DSWE. sAUC for diagnosis of cirrhosis were: 0.89 for VCTE, 0.90 for MRE, 0.90 for pSWE and 0.88 for 2DSWE. MRE had sAUC of 0.83 for diagnosis of NASH. Three (4%) studies reported intention-to-diagnose analyses and 15 (18%) studies reported diagnostic accuracy against pre-specified cut-offs.

CONCLUSIONS

When elastography index tests are acquired successfully, they have acceptable diagnostic accuracy for advanced fibrosis and cirrhosis. The potential clinical impact of these index tests cannot be assessed fully as intention-to-diagnose analyses and validation of pre-specified thresholds are lacking.

LAY SUMMARY

Non-invasive tests that measure liver stiffness or use magnetic resonance imaging (MRI) have been suggested as alternatives to liver biopsy for assessing the severity of liver scarring (fibrosis) and fatty inflammation (steatohepatitis) in patients with non-alcoholic fatty liver disease (NAFLD). In this study, we summarise the results of previously published studies on how accurately these non-invasive tests can diagnose liver fibrosis and inflammation, using liver biopsy as the reference. We found that some techniques that measure liver stiffness had a good performance for the diagnosis of severe liver scarring.

Systematic Review with Meta-Analyses: Diagnostic Accuracy of FibroMeter Tests in Patients with Non-Alcoholic Fatty Liver Disease

Early detection of liver fibrosis is crucial to select the correct care path for patients with non-alcoholic fatty liver disease (NAFLD). Here, we systematically review the evidence on the performance of FibroMeter versions in detecting different levels of fibrosis in patients with NAFLD. We searched four databases (Medline, Embase, the Cochrane library, and Web of Science) to find studies that included adults with NAFLD and biopsy-confirmed fibrosis (F1 to F4), compared with any version of FibroMeter. Two independent researchers screened the references, collected the data, and assessed the methodological quality of the included studies. We used a bivariate logit-normal random effects model to produce meta-analyses. From 273 references, 12 studies were eligible for inclusion, encompassing data from 3425 patients. Meta-analyses of the accuracy in detecting advanced fibrosis (F ≥ 3) were conducted for FibroMeter Virus second generation (V2G), NAFLD, and vibration controlled transient elaFS3stography (VCTE). FibroMeter VCTE showed the best diagnostic accuracy in detecting advanced fibrosis (sensitivity: 83.5% (95%CI 0.58–0.94); specificity: 91.1% (95%CI 0.89–0.93)), followed by FibroMeter V2G (sensitivity: 83.1% (95%CI 0.73–0.90); specificity: 84.4% (95%CI 0.62–0.95)) and FibroMeter NAFLD (sensitivity: 71.7% (95%CI 0.63–0.79); specificity: 82.8% (95%CI 0.71–0.91)). No statistically significant differences were found between the different FibroMeter versions. FibroMeter tests showed acceptable sensitivity and specificity in detecting advanced fibrosis in patients with NAFLD, but an urge to conduct head-to-head comparison studies in patients with NAFLD of the different FibroMeter tests remains.

Perspectives on Precision Medicine Approaches to NAFLD Diagnosis and Management

Precision medicine defines the attempt to identify the most effective approaches for specific subsets of patients based on their genetic background, clinical features, and environmental factors. Nonalcoholic fatty liver disease (NAFLD) encompasses the alcohol-like spectrum of liver disorders (steatosis, steatohepatitis with/without fibrosis, and cirrhosis and hepatocellular carcinoma) in the nonalcoholic patient. Recently, disease renaming to MAFLD [metabolic (dysfunction)-associated fatty liver disease] and positive criteria for diagnosis have been proposed. This review article is specifically devoted to envisaging some clues that may be useful to implementing a precision medicine-oriented approach in research and clinical practice. To this end, we focus on how sex and reproductive status, genetics, intestinal microbiota diversity, endocrine and metabolic status, as well as physical activity may interact in determining NAFLD/MAFLD heterogeneity. All these factors should be considered in the individual patient with the aim of implementing an individualized therapeutic plan. The impact of considering NAFLD heterogeneity on the development of targeted therapies for NAFLD subgroups is also extensively discussed.

From the origin of NASH to the future of metabolic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) has become the most common cause of chronic liver disease worldwide. Understanding the pathological and molecular hallmarks from its first description to definitions of disease entities, classifications and molecular phenotypes is crucial for both appropriate clinical management and research in this complex disease. We provide an overview through almost two hundred years of clinical research from the beginnings as a nebulous disease entity of unknown origin in the 19th century to the most frequent and vigorously investigated liver disease today. The clinical discrimination between alcohol-related liver disease and NAFLD was uncommon until the 1950s and likely contributed to the late acceptance of NAFLD as a metabolic disease entity for long time. Although the term 'fatty liver hepatitis' first appeared in 1962, it was in 1980 that the term 'non-alcoholic steatohepatitis' (NASH) was coined and the histopathological hallmarks that are still valid today were defined. The 2005 NASH Clinical Research Network scoring was the first globally accepted grading and staging system for the full spectrum of NAFLD and is still used to semiquantify main histological features. In 2021, liver biopsy remains the only diagnostic procedure that can reliably assess the presence of NASH and early fibrosis but increasing efforts are made towards non-invasive testing and molecular classification of NAFLD subtypes.

Epidemiology, Pathogenesis, Diagnosis and Emerging Treatment of Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, with an estimated rising prevalence, in concert with the epidemics of obesity and type 2 diabetes. The pathogenesis of NAFLD is not fully elucidated. Besides weight gain and insulin resistance, many other factors seem to contribute, including adipokines, gut microbiota and genetic predisposition. The disease starts as hepatic steatosis, which may proceed to nonalcoholic steatohepatitis (NASH); if fibrosis is added, the risk of cirrhosis and/or hepatocellular carcinoma is augmented. Liver biopsy is considered the gold standard for the diagnosis and staging of NAFLD; the early use of reliable and easily applied diagnostic tools, such as noninvasive biomarkers, is needed to identify patients at different-preferably early-stages of disease however. Whilst lifestyle modification is the first step to manage NAFLD, there is poor compliance, leading to the need of drug therapy. Accordingly, a variety of medications is under investigation. Given the multifaceted pathophysiology of NAFLD, probably, a combination of approaches in an individualized basis may be a more appropriate management. This review summarizes evidence on the epidemiology, pathogenesis, diagnosis and treatment of NAFLD.

Assessment of hepatic fibrosis and steatosis by vibration-controlled transient elastography and controlled attenuation parameter versus non-invasive assessment scores in patients with non-alcoholic fatty liver disease

Background

Non-alcoholic fatty liver disease (NAFLD) is regarded as the most common liver disease in the twenty-first century, and a condition leaving individuals at increased risk of extra-hepatic morbidity. Liver biopsy has long been regarded as the gold standard for diagnosis and prognostication of patients with NAFLD. However, due to its invasive nature and potential complications (e.g., bleeding), other methods for non-invasive laboratory and radiological assessment of hepatic steatosis and fibrosis in NAFLD have evolved and include scores such as AST/Platelet Ratio Index (APRI), Fibrosis-4 (FIB-4) score, NAFLD fibrosis score (NFS), and fatty liver index (FLI), in addition to radiological methods such as transient elastography (TE), which is a well-validated non-invasive ultrasound-based technique for assessment of hepatic fibrosis. Recently, novel development of controlled attenuation parameter (CAP) in TE allowed simultaneous assessment of hepatic steatosis. This provided a chance to assess both hepatic fibrosis and steatosis in the same setting and without any unwanted complications. This study aimed at assessing the role of TE and CAP versus other non-invasive assessment scores for liver fibrosis and steatosis in patients with NAFLD.

Results

This study included 90 patients diagnosed with NAFLD based on abdominal ultrasonography, body mass index, and serum liver enzymes. All patients were assessed with TE and non-invasive scores (APRI score, FIB-4 score, NFS, and FLI). There was a highly significant positive correlation between fibrosis and steatosis grades assessed by TE and other non-invasive respective scores. Both TE and CAP achieved acceptable sensitivity and specificity compared to other non-invasive assessment methods.

Conclusions

TE with CAP can be used as a screening method for patients suspected with NAFLD or patients without a clear indication for liver biopsy. CAP allows a non-invasive method of assessment of hepatic steatosis in patients with NAFLD.

Serum Scoring and Quantitative Magnetic Resonance Imaging in Intestinal Failure-Associated Liver Disease: A Feasibility Study

(1) Background: Intestinal failure-associated liver disease (IFALD) in adults is characterized by steatosis with variable progression to fibrosis/cirrhosis. Reference standard liver biopsy is not feasible for all patients, but non-invasive serological and quantitative MRI markers for diagnosis/monitoring have not been previously validated. Here, we examine the potential of serum scores and feasibility of quantitative MRI used in non-IFALD liver diseases for the diagnosis of IFALD steatosis; (2) Methods: Clinical and biochemical parameters were used to calculate serum scores in patients on home parenteral nutrition (HPN) with/without IFALD steatosis. A sub-group underwent multiparameter quantitative MRI measurements of liver fat fraction, iron content, tissue T1, liver blood flow and small bowel motility; (3) Results: Compared to non-IFALD (n = 12), patients with IFALD steatosis (n = 8) demonstrated serum score elevations in Enhanced Liver Fibrosis (p = 0.032), Aspartate transaminase-to-Platelet Ratio Index (p < 0.001), Fibrosis-4 Index (p = 0.010), Forns Index (p = 0.001), Gamma-glutamyl transferase-to-Platelet Ratio Index (p = 0.002) and Fibrosis Index (p = 0.001). Quantitative MRI scanning was feasible in all 10 sub-group patients. Median liver fat fraction was higher in IFALD steatosis patients (10.9% vs 2.1%, p = 0.032); other parameter differences were non-significant; (4) Conclusion: Serum scores used for non-IFALD liver diseases may be useful in IFALD steatosis. Multiparameter MRI is feasible in patients on HPN.

Measurement of Liver Stiffness with 2D-Shear Wave Elastography (2D-SWE) in Bariatric Surgery Candidates Reveals Acceptable Diagnostic Yield Compared to Liver Biopsy

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is common among severely obese patients. Two-dimensional shear wave elastography (2D-SWE) has been validated as a noninvasive diagnostic tool for liver stiffness measurement. However, the technical feasibility and accuracy of this method in severely obese patients are still under debate.

OBJECTIVE

We aimed to assess the diagnostic accuracy of 2D-SWE in bariatric surgery candidates in comparison with the gold standard liver biopsy.

METHODS

Ninety severely obese candidates for bariatric surgery were included. Liver stiffness was measured using 2D-SWE 14 days before liver biopsy. Liver biopsy was taken on the day of surgery. The area under the receiver operating curve (AUROC) was calculated for the staging of liver fibrosis.

RESULTS

2D-SWE was performed in 97.3% of patients successfully. Histologic stages of fibrosis (F0-F4) were detected in 34.2%, 36%, 6.3%, 3.6%, and 0.9% of patients, respectively. The AUROC for 2D-SWE was 0.77 for F1, 0.72 for F2, 0.77 for F3, and 0.70 for F4. In univariate analysis, 2D-SWE values were correlated with BMI, waist circumference, NAFLD activity score (NAS), and steatosis, whereas these components did not affect liver stiffness in multivariate analysis.

CONCLUSION

Two-dimensional shear wave elastography of the liver can be feasible and has good accuracy in severely obese candidates for bariatric surgery. Therefore, 2D-SWE may be a good option for assessing liver fibrosis, especially in the early stages of fibrosis to lessen complications of surgery in this population. However, this method should be applied on a larger scale for late stage of fibrosis.

Direct comparison of the specialised blood fibrosis tests FibroMeterV2G and Enhanced Liver Fibrosis score in patients with non-alcoholic fatty liver disease from tertiary care centres

BACKGROUND

The Enhanced Liver Fibrosis score (ELF) and the FibroMeter^V2G are two specialized blood fibrosis tests which include direct markers of liver fibrosis. They have been shown to be more accurate than the simple blood fibrosis tests FIB4 and the non-alcoholic fatty liver disease (NAFLD) fibrosis score (NFS).

AIMS

To directly compare the accuracies of ELF and FibroMeter^V2G for the non-invasive diagnosis of liver fibrosis in NAFLD.

METHODS

Four hundred and seventeen patients with biopsy-proven NAFLD were enrolled from two tertiary care centres. Four blood fibrosis tests were calculated: ELF, FibroMeter^V2G , NFS, and FIB4. Advanced fibrosis F3/4 on liver biopsy (NASH CRN scoring) was the primary endpoint.

RESULTS

Areas under the receiver operating characteristic (AUROC) curve for advanced fibrosis were not significantly different between the direct markers of liver fibrosis (hyaluronate, PIIINP, TIMP-1, alpha2-macroglobulin) and the simple blood fibrosis tests NFS and FIB4. ELF (0.793 ± 0.022) and FibroMeter^V2G (0.804 ± 0.021) had significantly higher AUROC than NFS (0.722 ± 0.025, P < .010) and FIB4 (0.739 ± 0.024, P < .020). AUROC for advanced fibrosis and Obuchowski index were not significantly different between ELF and FibroMeter^V2G . Algorithms using first ELF or FibroMeter^V2G and then liver biopsy in case of undetermined diagnosis provided high diagnostic accuracy for advanced fibrosis: 90% sensitivity, 90% specificity, 93% negative predictive value, 85% positive predictive value, and 90% correct classification. In these algorithms, the rate of liver biopsy was 45.3% with ELF versus 39.3% with FibroMeter^V2G (P = .065).

CONCLUSIONS

ELF and FibroMeter^V2G have equal accuracy and perform better than the simple FIB4 and NFS tests for the non-invasive diagnosis of advanced liver fibrosis in patients with NAFLD from tertiary care centres.

Oral Diseases Associated with Nonalcoholic Fatty Liver Disease in the United States

The US prevalence of nonalcoholic fatty liver disease (NAFLD) is 30.6% and increasing. NAFLD shares some risk factors with periodontitis and dental caries. We explored the association between NAFLD and several oral conditions among US adults, using data from the cross-sectional, nationally representative National Health and Nutrition Examination Survey (NHANES), 1988 to 1994. NAFLD was assessed with ultrasonography (USON), the screening gold standard not available in the more recent NHANES, and the noninvasive Fibrosis Score (FS), Fatty Liver Index (FLI), and US Fatty Liver Index (US-FLI) as other screening alternatives. There were 5,421 eligible dentate adults aged 21 to 74 y with complete relevant data, with transferrin levels ≤50%, without hepatitis B or C, who were not heavy drinkers. Multivariable models were developed to examine the independent effects of moderate-severe periodontitis, untreated dental caries, caries experience, and tooth loss (<20 teeth) on NAFLD while controlling for clinical, biological, and sociodemographic factors. Weighted estimates for odds ratios (ORs) and 95% CIs were calculated with logistic regression. Between 17% and 24% of adults had NAFLD depending on the classification criteria. In adjusted models, as compared with those with better oral health, adults with <20 teeth were more likely to have NAFLD depending on the measure (USON: OR = 1.50, 95% CI = 1.11 to 2.02; FS: OR = 4.36, 95% CI = 3.47 to 5.49; FLI: OR = 1.99, 95% CI = 1.52 to 2.59; US-FLI: OR = 2.32, 95% CI = 1.79 to 3.01). People with moderate-severe periodontitis were more likely to have NAFLD (USON: OR = 1.54, 95% CI = 1.06 to 2.24; FS: OR = 3.10, 95% CI = 2.31 to 4.17; FLI: OR = 1.61, 95% CI = 1.13 to 2.28; US-FLI: OR = 2.21, 95% CI = 1.64 to 2.98). People with any untreated caries were more likely to have NAFLD (USON: OR = 1.51, 95% CI = 1.20 to 1.90; FLI: OR = 1.80, 95% CI = 1.33 to 2.44). NAFLD was associated with tooth loss, periodontitis, and, for some NAFLD measures, untreated dental caries but not overall caries experience after controlling for several key sociodemographic and behavioral factors. Results suggest that further evaluation is needed to better understand this health-oral health interrelationship and potential opportunities for medical-dental integration.

Improvements in clinical characteristics of patients with non-alcoholic fatty liver disease, after an intervention based on the Mediterranean lifestyle: a randomised controlled clinical trial

Lifestyle interventions remain the cornerstone therapy for non-alcoholic fatty liver disease (NAFLD). This randomised controlled single-blind clinical trial investigated the effect of Mediterranean diet (MD) or Mediterranean lifestyle, along with weight loss, in NAFLD patients. In all, sixty-three overweight/obese patients (50 (sd 11) years, BMI=31·8 (sd 4·5) kg/m2, 68 % men) with ultrasonography-proven NAFLD (and elevated alanine aminotransferase (ALT) and/or γ-glutamyl transpeptidase (GGT) levels) were randomised to the following groups: (A) control group (CG), (B) Mediterranean diet group (MDG) or (C) Mediterranean lifestyle group (MLG). Participants of MDG and MLG attended seven 60-min group sessions for 6 months, aiming at weight loss and increasing adherence to MD. In the MLG, additional guidance for increasing physical activity and improving sleep habits were given. Patients in CG received only written information for a healthy lifestyle. At the end of 6 months, 88·8 % of participants completed the study. On the basis of intention-to-treat analysis, both MDG and MLG showed greater weight reduction and higher adherence to MD compared with the CG (all P<0·05) at the end of intervention. In addition, MLG increased vigorous exercise compared with the other two study groups (P<0·001) and mid-day rest/naps compared with CG (P=0·04). MLG showed significant improvements in ALT levels (i.e. ALT<40 U/l (P=0·03) and 50 % reduction of ALT levels (P=0·009)) and liver stiffness (P=0·004) compared with CG after adjusting for % weight loss and baseline values. MDG improved only liver stiffness compared with CG (P<0·001) after adjusting for the aforementioned variables. Small changes towards the Mediterranean lifestyle, along with weight loss, can be a treatment option for patients with NAFLD.

Novel Serum Biomarkers for Noninvasive Diagnosis and Screening of Nonalcoholic Fatty Liver Disease-Related Hepatic Fibrosis

Nonalcoholic fatty liver disease (NAFLD) is a growing global public health concern and becoming the leading cause of liver disease worldwide. The estimated global prevalence of NAFLD is ∼25% depending on the country and the assessment method used to establish the diagnosis. Meta-analyses suggest that the highest prevalence is in the Middle East (31.8%) and South America (30.4%), and the lowest in Africa (13.5%). In the United States, between 75 and 100 million individuals were estimated to have NAFLD. This important disease is associated with increased incidence of liver-related deaths, hepatocarcinoma, and overall mortality. Fibrosis stage, among other histological characteristics, is the most critical factor in predicting all-cause and disease-specific mortality in NAFLD. The ability to detect fibrosis early in NAFLD patients is critical in controlling mortality associated with this highly prevalent disease. We present here an expert review on recent advances in novel blood biomarkers, for example, the Wisteria floribunda agglutinin-positive mac-2 binding protein (WFA⁺-M2BP), type IV collagen 7S, chitinase 3 like 1 (CHI3L1; YKL-40), and insulin-like growth factor-1 (IGF-1). Algorithms using multiple biomarkers such as alpha-2-macroglobulin, mir34a, YKL-40, and hemoglobin A1c (HbA1c; NIS4), enhanced liver fibrosis (ELF), Hepascore, FibroMeter, FibroTest, FIBROSpect, FIB-C3, and ADPAPT are highlighted. Novel technologies such as tandem mass spectrometry to directly measure protein turnover rate of the key proteins involved in hepatic fibrosis, as an indicator of fibrogenesis, are also discussed. In conclusion, NAFLD is a growing global health problem that warrants long-term funding, research, and training of scholars across the fields of public health diagnostics, systems sciences, nutrition, hepatology, and clinical oncology.

Hepatic artery resistive index as surrogate marker for fibrosis progression in NAFLD patients: A clinical perspective

Ultrasound (US) can reveal the presence of steatosis in non-alcoholic fatty liver disease (NAFLD), but its diagnostic accuracy to reveal signs of fibrosis is low except in advanced stages of disease (e.g. cirrhosis). Current guidelines suggest the use of clinical algorithms, such as the NAFLD fibrosis score, and elastography to predict the progression of fibrosis, and the integration of elastography improves the detection accuracy of liver stiffness. However, there is a lack of evidence about the correlation between clinical algorithms and conventional US, and elastography is limited by the relative low diffusion, necessity of training, and loss of diagnostic accuracy in patients with high body mass index (BMI), waist circumference, or increased thickness of parietal walls, with consequent significant rates of failure of measurement of liver stiffness. Recently, the measurement of hepatic artery resistive index (HARI) has demonstrated a significant positive correlation with fibrosis degree, as measured with NAFLD fibrosis score, suggesting that the fibrous tissue accumulation may result in increased arterial rigidity and, therefore, in a rise of resistance to flow, and that the different tissue composition of the liver (adipose versus fibrous) can influence HARI differently. These issues should be further investigated because some aspects are still unknown. The limited data currently justify the need of larger, prospective studies aimed at assessing whether HARI correlates with elastography results. In view of their effect on weight loss, serum lipid concentration, and hepatic arterial flow hemodynamics, it could be interesting to evaluate if lifestyle and diet changes can influence significantly HARI values in NAFLD patients.

Non-alcoholic fatty liver disease: Relationship with cardiovascular risk markers and clinical endpoints

Non-alcoholic fatty liver disease (NAFLD) is a common diagnosis and is increasing in prevalence worldwide. NAFLD is usually asymptomatic at presentation; progression of the disease is unpredictable, leading to the development of a variety of techniques for screening, diagnosis and risk stratification. Clinical methods in current use include serum biomarker panels, hepatic ultrasound, magnetic resonance imaging, and liver biopsy. NAFLD is strongly associated with the metabolic syndrome, and the most common cause of death for people with the condition is cardiovascular disease. Whether NAFLD is an independent cardiovascular risk factor needs exploration. NAFLD has been associated with surrogate markers of cardiovascular disease such as carotid intima-media thickness, the presence of carotid plaque, brachial artery vasodilatory responsiveness and CT coronary artery calcification score. There is no effective medical treatment for NAFLD and evidence is lacking regarding the efficacy of interventions in mitigating cardiovascular risk. Health care professionals managing patients with NAFLD should tackle the issue with early identification of risk factors and aggressive modification. Current management strategies therefore comprise lifestyle change, with close attention to known cardiovascular risk factors.

Noninvasive imaging biomarker assessment of liver fibrosis by elastography in NAFLD

NAFLD is a global epidemic. The prevalence of NAFLD is 20-30% in North America, northern Europe, Australia, Japan, India and China. It is crucial that patients with NAFLD receive an assessment for their risk of advanced fibrosis, which increases the risk of hepatocellular carcinoma and other complications of cirrhosis. Risk stratification that is efficient, cost-effective, patient-centred and evidence-based is one of the most important issues facing clinicians who care for those with liver disease. Given patients' preference to avoid liver biopsy, noninvasive alternatives to assess liver fibrosis are in high demand. The most accurate noninvasive methods are based on liver elastography. Research on these techniques - which include vibration-controlled transient elastography (VCTE), magnetic resonance elastography (MRE), shear-wave elastography and acoustic radiation force impulse - has proliferated. Unfortunately, the literature has not kept pace with clinical practice. There is limited guidance for how clinicians should anticipate and manage the pitfalls of these tests. Furthermore, guidance is unavailable for clinicians regarding the optimal incorporation of VCTE, MRE or the emerging elastographic techniques into their clinical strategy, particularly for patients with NAFLD. In this Review, we summarize the available evidence, highlight gaps to address in further research and explore optimization of these techniques in clinical practice.

Systematic review and meta-analysis: non-invasive detection of non-alcoholic fatty liver disease related fibrosis in the obese

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a significant disease burden in obesity. Liver fibrosis is an important prognostic factor in NAFLD, and detection is vital. The pathophysiological changes of obesity can alter the accuracy of non-invasive NAFLD tests. We aimed to review current evidence for common non-invasive tests for NAFLD-related fibrosis in obesity.

METHODS

We systematically searched for studies assessing the diagnostic accuracy of 11 biomarker panels and elastography techniques for NAFLD-related fibrosis in obesity. Meta-analyses were performed where possible.

RESULTS

Thirty-eight studies were identified assessing the selected tests in obese populations. Simple biomarker panels (e.g. NAFLD fibrosis score) were the most validated. Evidence showed better accuracy of complex biomarker panels (NAFLD fibrosis score: summary receiver operator characteristic [SROC] 0.795-0.813 vs. enhanced liver fibrosis: SROC 0.962); however, these were poorly validated in obesity. Elastography techniques were better studied and had high diagnostic accuracy (transient elastography: SROC 0.859; magnetic resonance elastography: SROC 0.965) but were limited by BMI-dependent failure. Limited evidence was found to validate the accuracy of any test in exclusively obese populations.

CONCLUSION

In obese subjects, complex biomarker panels and elastography have been reasonable to good accuracy for NAFLD-related fibrosis; however, these methods have not been well validated. Further study in this high-risk population is needed.

The rising incidence of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the leading cause of liver disease in the United States and will soon be the leading indication for liver transplantation. NAFLD can lead to cirrhosis of the liver and is usually asymptomatic. Prompt referral to a hepatologist may halt the morbidity and mortality associated with NAFLD.

Exercise restores bioavailability of hydrogen sulfide and promotes autophagy influx in livers of mice fed with high-fat diet

In the gold standard treatment for nonalcoholic fatty liver disease (NAFLD), exercise training has been shown to effectively improve nonalcoholic steatohepatitis (NASH). However, limited data are available about the underlying mechanisms involved. This work was undertaken to investigate the mechanisms underlying the beneficial effect of exercise training on high-fat diet (HFD)-induced NAFLD in mice. Male mice were fed with HFD and given moderate-intensity exercise for 24 weeks. Exercise training lowered mass gain, attenuated systemic insulin resistance and glucose intolerance, and mitigated hepatic steatosis and fibrosis in mice fed with HFD. Exercise training improved mitochondrial function and enhanced mitochondrial β-oxidation in livers of HFD-fed mice. Exercise training enhanced hydrogen sulfide (H2S) levels in plasma and livers, and mRNA expression of cystathionine β-synthase (CBS), cystathionine γ-lyase (CES), and 3-mercaptopyruvate sulfurtransferase (3-MST) in livers of HFD-fed mice. Exercise training had no significant effect on the ratio of LC3-II/LC3-I, but decreased p62 protein expression in livers of HFD-fed mice. Additionally, exercise training reduced formation of malondialdehyde, enhanced ratio of GSH/GSSG, and down-regulated expression of TNF-α and IL-6 in livers of HFD-fed mice. Exercise training restored bioavailability of H2S and promoted autophagy influx in livers, which might contribute to its benefit on HFD-induced NAFLD.

Identifying nonalcoholic fatty liver disease patients with active fibrosis by measuring extracellular matrix remodeling rates in tissue and blood

Excess collagen synthesis (fibrogenesis) in the liver plays a causal role in the progression of nonalcoholic fatty liver disease (NAFLD). Methods are needed to identify patients with more rapidly progressing disease and to demonstrate early response to treatment. We describe here a novel method to quantify hepatic fibrogenesis flux rates both directly in liver tissue and noninvasively in blood. Twenty-one patients with suspected NAFLD ingested heavy water (² H₂ O, 50-mL aliquots) two to three times daily for 3-5 weeks prior to a clinically indicated liver biopsy. Liver collagen fractional synthesis rate (FSR) and plasma lumican FSR were measured based on ² H labeling using tandem mass spectrometry. Patients were classified by histology for fibrosis stage (F0-F4) and as having nonalcoholic fatty liver or nonalcoholic steatohepatitis (NASH). Magnetic resonance elastography measurements of liver stiffness were also performed. Hepatic collagen FSR in NAFLD increased with advancing disease stage (e.g., higher in NASH than nonalcoholic fatty liver, positive correlation with fibrosis score and liver stiffness) and correlated with hemoglobin A1C. In addition, plasma lumican FSR demonstrated a significant correlation with hepatic collagen FSR.

CONCLUSION

Using a well-characterized cohort of patients with biopsy-proven NAFLD, this study demonstrates that hepatic scar in NASH is actively remodeled even in advanced fibrosis, a disease that is generally regarded as static and slowly progressive. Moreover, hepatic collagen FSR correlates with established risks for fibrotic disease progression in NASH, and plasma lumican FSR correlates with hepatic collagen FSR, suggesting applications as direct or surrogate markers, respectively, of hepatic fibrogenesis in humans. (Hepatology 2017;65:78-88).

Micronutrient Antioxidants and Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is one of the most important chronic liver diseases worldwide and has garnered increasing attention in recent decades. NAFLD is characterized by a wide range of liver changes, from simple steatosis to nonalcoholic steatohepatitis, cirrhosis, and hepatocellular carcinoma. The blurred pathogenesis of NAFLD is very complicated and involves lipid accumulation, insulin resistance, inflammation, and fibrogenesis. NAFLD is closely associated with complications such as obesity, diabetes, steatohepatitis, and liver fibrosis. During the progression of NAFLD, reactive oxygen species (ROS) are activated and induce oxidative stress. Recent attempts at establishing effective NAFLD therapy have identified potential micronutrient antioxidants that may reduce the accumulation of ROS and finally ameliorate the disease. In this review, we present the molecular mechanisms involved in the pathogenesis of NAFLD and introduce some dietary antioxidants that may be used to prevent or cure NAFLD, such as vitamin D, E, and astaxanthin.

Discrimination of Nonalcoholic Steatohepatitis Using Transient Elastography in Patients with Nonalcoholic Fatty Liver Disease

Background/aims

The accuracy of noninvasive markers to discriminate nonalcoholic steatohepatitis (NASH) is unsatisfactory. We investigated whether transient elastography (TE) could discriminate patients with NASH from those with nonalcoholic fatty liver disease (NAFLD).

Methods

The patients suspected of NAFLD who underwent liver biopsy and concomitant TE were recruited from five tertiary centers between November 2011 and December 2013.

Results

The study population (n = 183) exhibited a mean age of 40.6 years and male predominance (n = 111, 60.7%). Of the study participants, 89 (48.6%) had non-NASH and 94 (51.4%) had NASH. The controlled attenuation parameter (CAP) and liver stiffness (LS) were significantly correlated with the degrees of steatosis (r = 0.656, P<0.001) and fibrosis (r = 0.714, P<0.001), respectively. The optimal cut-off values for steatosis were 247 dB/m for S1, 280 dB/m for S2, and 300 dB/m for S3. Based on the independent predictors derived from multivariate analysis [P = 0.044, odds ratio (OR) 4.133, 95% confidence interval (CI) 1.037–16.470 for CAP>250 dB/m; P = 0.013, OR 3.399, 95% CI 1.295–8.291 for LS>7.0 kPa; and P<0.001, OR 7.557, 95% CI 2.997–19.059 for Alanine aminotransferase>60 IU/L], we developed a novel CLA model for discriminating patients with NASH. The CLA model showed good discriminatory capability, with an area under the receiver operating characteristic curve (AUROC) of 0.812 (95% CI 0.724–0.880). To assess discriminatory power, the AUROCs, as determined by the bootstrap method, remained largely unchanged between iterations, with an average value of 0.833 (95% CI 0.740–0.893).

Conclusion

This novel TE-based CLA model showed acceptable accuracy in discriminating NASH from simple steatosis. However, further studies are required for external validation.

The Role of Vitamins in the Pathogenesis of Non-alcoholic Fatty Liver Disease

The incidence of non-alcoholic fatty liver disease (NAFLD) is rising rapidly in parallel with obesity rates. The underlying pathogenesis of NAFLD remains an enigma but is largely influenced by individual lifestyle choices involving diet and exercise. Therefore, studies have highlighted the importance of calorie reduction and macronutrient composition (eg, carbohydrate and fat) in modifying disease outcomes. Micronutrients are also believed to play a role in disease progression. There are now an increasing number of studies linking vitamins with NAFLD, particularly vitamin E, and the supplementation of several different vitamins has been demonstrated as a promising therapeutic option in the treatment of NAFLD. This review provides a broad overview of the potential role of vitamins in NAFLD development and disease management.

Diagnostic usefulness of FibroMeter VCTE for hepatic fibrosis in patients with nonalcoholic fatty liver disease

BACKGROUND

Liver fibrosis is an important prognostic determinant in patients with nonalcoholic fatty liver disease (NAFLD). The FibroMeter VCTE is a diagnostic tool comprising both biochemical markers and transient elastography (TE) originally developed for the diagnosis of fibrosis in patients with chronic viral hepatitis. In this pilot study, we investigated the diagnostic performance of the FibroMeter VCTE tool for determining fibrosis in patients with biopsy-proven NAFLD. Its diagnostic accuracy was also compared with those of the NAFLD fibrosis score (NFSA) and TE alone.

PATIENTS AND METHODS

FibroMeter VCTE, NFSA, and TE were determined in 52 patients with NAFLD. The results of liver biopsies were considered the gold standard. Areas under the receiver operating characteristic curve were used to express the diagnostic accuracy of each test.

RESULTS

Significant (F≥2) and severe (F≥3) fibrosis were detected in 20 (38%) and 10 (19%) patients, respectively. The sensitivity of FibroMeter VCTE, NFSA, and TE for detecting significant fibrosis was 70, 65, and 75%, respectively, whereas specificity was 88, 81, and 78%. The sensitivity of FibroMeter VCTE, NFSA, and TE for diagnosing severe fibrosis was 90, 90, and 100%, respectively, whereas specificity was 93, 78, and 76%. Receiver operating characteristic analysis showed that FibroMeter VCTE had a significantly larger areas under the receiver operating characteristic curve (0.968) compared with both NFSA (0.833, P<0.001) and TE (0.922, P<0.05) for the detection of severe fibrosis.

CONCLUSION

Our preliminary findings indicate that FibroMeter VCTE is superior to both NFSA and TE for the diagnosis of severe fibrosis in patients with NAFLD.