Pathologic criteria for nonalcoholic steatohepatitis: interprotocol agreement and ability to predict liver-related mortality

Validity criteria for the diagnosis of fatty liver by M probe-based controlled attenuation parameter

BACKGROUND & AIMS

Controlled attenuation parameter (CAP) can be performed together with liver stiffness measurement (LSM) by transient elastography (TE) and is often used to diagnose fatty liver. We aimed to define the validity criteria of CAP.

METHODS

CAP was measured by the M probe prior to liver biopsy in 754 consecutive patients with different liver diseases at three centers in Europe and Hong Kong (derivation cohort, n=340; validation cohort, n=414; 101 chronic hepatitis B, 154 chronic hepatitis C, 349 non-alcoholic fatty liver disease, 37 autoimmune hepatitis, 49 cholestatic liver disease, 64 others; 277 F3-4; age 52±14; body mass index 27.2±5.3kg/m²). The primary outcome was the diagnosis of fatty liver, defined as steatosis involving ≥5% of hepatocytes.

RESULTS

The area under the receiver-operating characteristics curve (AUROC) for CAP diagnosis of fatty liver was 0.85 (95% CI 0.82-0.88). The interquartile range (IQR) of CAP had a negative correlation with CAP (r=-0.32, p<0.001), suggesting the IQR-to-median ratio of CAP would be an inappropriate validity parameter. In the derivation cohort, the IQR of CAP was associated with the accuracy of CAP (AUROC 0.86, 0.89 and 0.76 in patients with IQR of CAP <20 [15% of patients], 20-39 [51%], and ≥40dB/m [33%], respectively). Likewise, the AUROC of CAP in the validation cohort was 0.90 and 0.77 in patients with IQR of CAP <40 and ≥40dB/m, respectively (p=0.004). The accuracy of CAP in detecting grade 2 and 3 steatosis was lower among patients with body mass index ≥30kg/m² and F3-4 fibrosis.

CONCLUSIONS

The validity of CAP for the diagnosis of fatty liver is lower if the IQR of CAP is ≥40dB/m. Lay summary: Controlled attenuation parameter (CAP) is measured by transient elastography (TE) for the detection of fatty liver. In this large study, using liver biopsy as a reference, we show that the variability of CAP measurements based on its interquartile range can reflect the accuracy of fatty liver diagnosis. In contrast, other clinical factors such as adiposity and liver enzyme levels do not affect the performance of CAP.

Point shear wave ultrasound elastography with Esaote compared to real-time 2D shear wave elastography with supersonic imagine for the quantification of liver stiffness

PURPOSE

Different shear wave elastography (SWE) machines able to quantify liver stiffness (LS) have been recently introduced by various companies. The aim of this study was to investigate the agreement between point SWE with Esaote MyLab Twice (pSWE.ESA) and 2D SWE with Aixplorer SuperSonic (2D SWE.SSI). Moreover, we assessed the correlation of these machines with Fibroscan in a subgroup of patients.

METHODS

A total of 81 liver disease patients and 27 subjects without liver disease accessing the ultrasound lab were considered. Exclusion criteria were liver nodules, BMI >35, and severe comorbidities. LS was sampled from the same intercostal space with both pSWE.ESA and 2D SWE.SSI and values were tested with Lin's analysis and Bland-Altman analysis (B&A). Agreement between each SWE machine and Fibroscan was assessed in 26 liver disease patients with Spearman correlation.

RESULTS

Precision and accuracy between pSWE.ESA and 2D SWE.SSI were, respectively, 0.839 and 0.999. B&A showed a mean of only -0.2 kPa, with no systematic deviation between the techniques and limits of agreement at -11.6 and 11.3 kPa. Spearman's rho correlation versus Fibroscan was 0.849 for pSWE.ESA and 0.878 for 2D SWE.SSI. The relationship became less strict in the higher range of LS (≥15.2 kPa), corresponding to cirrhosis.

CONCLUSION

The overall degree of concordance of pSWE.ESA and 2D SWE.SSI in measuring LS resulted remarkable, also when compared with Fibroscan. The less strict correlation for patients with LS in the higher range would not affect the staging of disease as such patients are anyhow classified as cirrhotic.

Diagnostic Accuracy of Noninvasive Fibrosis Scores in a Population of Individuals With a Low Prevalence of Fibrosis

BACKGROUND & AIMS

Noninvasive scoring systems for fibrosis are increasingly used in the clinic and in research because of their ease of use, accessibility, and low cost. However, test performance characteristics were established in groups of patients with a high prevalence of advanced fibrosis; little is known about diagnostic accuracy in low-risk populations.

METHODS

In a cross-sectional study, 922 members of a general ambulatory population in Hong Kong (randomly selected; 18-70 years old) underwent clinical assessment from May 2008 through December 2010. All participants completed a standard questionnaire that collected information on age, sex, and history of smoking and alcohol use. Results of fasting blood tests and transient elastography were used as the reference standard to identify patients with advanced fibrosis. We assessed performance characteristics of 3 noninvasive fibrosis scoring systems: the nonalcoholic fatty liver disease fibrosis scoring system, the Fibrosis-4 scoring system, and aspartate transaminase to platelet ratio index, using standard thresholds. To calculate diagnostic test characteristics, we constructed a 2-by-2 table with the presence or absence of advanced fibrosis according to the transient elastography reading against the presence or absence of advanced fibrosis according to the scoring systems. Area under the receiver operating curve was calculated to assess overall diagnostic accuracy.

RESULTS

Of the 922 individuals evaluated by transient elastography, 749 had a valid reading and 15 had advanced fibrosis (2%). The specificity of noninvasive scores in detection of advanced fibrosis approximated 100% (95% confidence interval [CI], 99%-100%), with a negative predictive value of 98% (95% CI, 97%-99%) for all systems. However, the scoring systems detected fibrosis with a low level of sensitivity, ranging from 7% (95% CI, 0%-32%) to 13% (95% CI, 2%-40%). Positive predictive values ranged from 50% (95% CI, 7%-93%) to 67% (95% CI, 9%-99%). Their negative likelihood ratios ranged from 0.87 (95% CI, 0.71%-1.06%) to 0.93 (95% CI, 0.82%-1.07%); positive likelihood ratios were uninformative because of the small number of people with positive scores.

CONCLUSIONS

In low-risk populations, negative results from noninvasive scoring systems reliably exclude advanced fibrosis, without requirements for further tests. Positive test results are often a false-positive result and should prompt further testing.

Significant liver fibrosis assessed using liver transient elastography is independently associated with low bone mineral density in patients with non-alcoholic fatty liver disease

Background

Metabolic bone disorders frequently occur in patients with chronic liver disease; however, the association between liver fibrosis and bone mineral density in patients with non-alcoholic fatty liver disease (NAFLD) is unclear.

Methods

This is a cross-sectional analysis of 231 asymptomatic subjects (160 women, 61.6 years old) from a university hospital setting, between February 2012 and December 2014. Bone mineral density (BMD) was measured at the lumbar spine, femur neck, and total hip using dual-energy X-ray absorptiometry (DXA). Liver fibrosis and steatosis were assessed using transient elastography.

Results

Among a total of 231 individuals, 129 subjects (55.8%) had NAFLD. BMDs at lumbar spine, femur neck, and total hip were significantly lower in patients having NAFLD with significant fibrosis, compared with patients having NAFLD without significant fibrosis (Ps<0.005). In patients with NAFLD, significant liver fibrosis revealed marked negative correlations with BMD at the lumber spine (r = –0.19, P = 0.032), femur neck (r = –0.19, P = 0.034), and total hip (r = –0.21, P = 0.016). A multivariate linear regression analysis revealed that significant liver fibrosis was independently correlated with low BMD at the femur neck (β = –0.18, P = 0.039) and total hip (β = –0.21, P = 0.005) after adjustment for age, sex, BMI, fasting plasma glucose, alanine aminotransferase, high-density lipoprotein cholesterol, and liver steatosis among patients with NAFLD. Using multivariable logistic regression, significant liver fibrosis was independently associated with overall osteopenia and osteoporosis in subjects having NAFLD (OR = 4.10, 95% CI = 1.02–16.45).

Conclusion

The presence of significant liver fibrosis assessed via TE was independently associated with low BMD in NAFLD subjects.

Characterization of transcriptional modules related to fibrosing-NAFLD progression

Based on the severity of liver fibrosis, low or high-risk profile of developing end-stage liver disease was present in nonalcoholic fatty liver disease (NAFLD). However, the mechanisms inducing transition from mild to advanced NAFLD are still elusive. We performed a system-level study on fibrosing-NAFLD by weighted gene co-expression network analysis (WGCNA) to identify significant modules in the network, and followed by functional and pathway enrichment analyses. Moreover, hub genes in the module were analyzed by network feature selection. As a result, fourteen distinct gene modules were identified, and seven modules showed significant associations with the status of NAFLD. Module preservation analysis confirmed that these modules can also be found in diverse independent datasets. After network feature analysis, the magenta module demonstrated a remarkably correlation with NAFLD fibrosis. The top hub genes with high connectivity or gene significance in the module were ultimately determined, including LUM, THBS2, FBN1 and EFEMP1. These genes were further verified in clinical samples. Finally, the potential regulators of magenta module were characterized. These findings highlighted a module and affiliated genes as playing important roles in the regulation of fibrosis in NAFLD, which may point to potential targets for therapeutic interventions.

Non-alcoholic fatty liver disease: An expanded review

Non-alcoholic fatty liver disease (NAFLD) encompasses the simple steatosis to more progressive steatosis with associated hepatitis, fibrosis, cirrhosis, and in some cases hepatocellular carcinoma. NAFLD is a growing epidemic, not only in the United States, but worldwide in part due to obesity and insulin resistance leading to liver accumulation of triglycerides and free fatty acids. Numerous risk factors for the development of NAFLD have been espoused with most having some form of metabolic derangement or insulin resistance at the core of its pathophysiology. NAFLD patients are at increased risk of liver-related as well as cardiovascular mortality, and NAFLD is rapidly becoming the leading indication for liver transplantation. Liver biopsy remains the gold standard for definitive diagnosis, but the development of noninvasive advanced imaging, biochemical and genetic tests will no doubt provide future clinicians with a great deal of information and opportunity for enhanced understanding of the pathogenesis and targeted treatment. As it currently stands several medications/supplements are being used in the treatment of NAFLD; however, none seem to be the "magic bullet" in curtailing this growing problem yet. In this review we summarized the current knowledge of NAFLD epidemiology, risk factors, diagnosis, pathogenesis, pathologic changes, natural history, and treatment in order to aid in further understanding this disease and better managing NAFLD patients.

Nonalcoholic fatty liver disease and the ongoing role of liver biopsy evaluation

Nonalcoholic fatty liver disease (NAFLD) is one of the most common underlying causes of chronically elevated liver tests and liver disease in adults and children worldwide and may be strongly suspected if not diagnosed by ever evolving and available serologic and imaging‐based noninvasive tests. However, the definitive diagnosis of the most progressive form of NAFLD, nonalcoholic steatohepatitis, and the identification of fibrosis stage still require liver biopsy evaluation as noninvasive testing has not replaced some of the specifics or the totality of information obtainable from liver biopsy. In this review, both the role and value of a liver biopsy evaluation in NAFLD/ nonalcoholic steatohepatitis are examined from publications related to a selected variety of settings. Details of the most commonly used semiquantitative methods of analysis are discussed, and some useful potential pitfalls for differential diagnostic consideration in liver biopsy interpretation are given. (Hepatology Communications 2017;1:370–378)

Nonalcoholic steatofibrosis independently predicts mortality in nonalcoholic fatty liver disease

Nonalcoholic steatohepatitis (NASH) is the progressive form of nonalcoholic fatty liver disease (NAFLD). The minimal pathologic criteria for NASH include hepatic steatosis, ballooning degeneration, and lobular inflammation. The resolution of NASH, which relies on the loss of ballooning degeneration, is subject to sampling and observer variability in pathologic interpretation. Ballooning is associated with advanced hepatic fibrosis in cross‐sectional studies but is not a predictor of mortality in NAFLD. Fibrosis staging, while still subject to some sampling variability, has less observer variability and is a robust predictor of liver‐related mortality in NAFLD. In this study, we hypothesize that, regardless of the diagnosis of NASH, the presence of steatofibrosis (steatosis accompanied by fibrosis) regardless of other pathologic features can also be a robust predictor of mortality in NAFLD. We used our previously reported cohort of patients with NAFLD with liver biopsies and long‐term mortality follow‐up. Cox proportional hazard models were used to determine the predictors of overall and liver‐related mortality. Of 209 enrolled NAFLD subjects, 97 can be classified as having steatofibrosis. During follow‐up (median 150 months), 64 (30.6%) patients died, with 18 (8.6%) from liver‐related causes. Adjusted for age, both diagnostic categories of NASH and steatofibrosis were significantly and similarly associated with liver‐related mortality (adjusted hazard ratio [aHR], 9.9; 95% confidence interval (CI), 1.3‐74.9; P = 0.027; aHR, 6.7; 95% CI, 1.5‐29.8; P = 0.013, respectively). However, only steatofibrosis showed independent association with overall mortality (aHR, 1.76; 95% CI, 1.02‐3.05; P = 0.043). Conclusion: Steatofibrosis and NASH are similarly associated with liver‐related mortality, but only steatofibrosis is associated with overall mortality in patients with NAFLD. Given the inherent observer variability in ballooning degeneration, a key diagnostic component of NASH, we suggest that steatofibrosis should be considered a viable diagnostic classification for NAFLD subjects at risk or adverse outcomes and provides a simpler endpoint for clinical trials of therapeutic agents. (Hepatology Communications 2017;1:421–428)

Dual-photon microscopy-based quantitation of fibrosis-related parameters (q-FP) to model disease progression in steatohepatitis

There is a need for further refinement of current histological systems for assessment of hepatic fibrosis in nonalcoholic fatty liver disease (NAFLD). This study evaluated hepatic fibrosis in NAFLD using dual-photon microscopy-based quantitation of fibrosis-related parameters (q-FPs). Fifty test cohort subjects and 42 validation cohort subjects with NAFLD and the full spectrum of fibrosis were studied. q-FPs were measured in specific predefined regions of interest (general, vessel, perisinusoid, and vascular septa). Seventy q-FPs had inter- and intraobserver concordance ≥0.8 and were related to the NASH Clinical Research Network fibrosis staging. Of these, 16 q-FPs with the strongest correlations (P < 0.001 for all) were entered in a principal component analysis model (odds ratio [OR] 7.8, P < 0.001), which separated any stage of fibrosis versus no fibrosis, and cirrhosis versus earlier stages with the areas under the receiver operating characteristic curves of 0.88 and 0.93 (P ≤ 0.01 for both), respectively. In an independent multivariable analysis, four q-FPs-the number of collagen strands (OR 8.5, P = 0.004), strand length (OR 12.0, P = 0.02), strand eccentricity (OR 8.3, P = 0.004), and strand solidity (OR 8.0, P = 0.003)-were independently associated with fibrosis stages and were used to model fibrosis along a continuous linear scale using desirability functions; this linear scale of fibrosis measurement was also related to fibrosis stage (P < 0.0001). The robustness of both the multivariable model and the linear scale of measurement was confirmed in the validation cohort.

CONCLUSION

The q-FP model provides an accurate reproducible method to evaluate fibrosis in NAFLD along a quantitative and continuous scale. (Hepatology 2017;65:1891-1903).

Increased risk of mortality by fibrosis stage in nonalcoholic fatty liver disease: Systematic review and meta-analysis

Liver fibrosis is the most important predictor of mortality in nonalcoholic fatty liver disease (NAFLD). Quantitative risk of mortality by fibrosis stage has not been systematically evaluated. We aimed to quantify the fibrosis stage-specific risk of all-cause and liver-related mortality in NAFLD. Through a systematic review and meta-analysis, we identified five adult NAFLD cohort studies reporting fibrosis stage-specific mortality (0-4). Using fibrosis stage 0 as a reference population, fibrosis stage-specific mortality rate ratios (MRRs) with 95% confidence intervals (CIs) for all-cause and liver-related mortality were estimated. The study is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Included were 1,495 NAFLD patients with 17,452 patient years of follow-up. Compared to NAFLD patients with no fibrosis (stage 0), NAFLD patients with fibrosis were at an increased risk for all-cause mortality, and this risk increased with increases in the stage of fibrosis: stage 1, MRR = 1.58 (95% CI 1.19-2.11); stage 2, MRR = 2.52 (95% CI 1.85-3.42); stage 3, MRR = 3.48 (95% CI 2.51-4.83); and stage 4, MRR = 6.40 (95% CI 4.11-9.95). The results were more pronounced as the risk of liver-related mortality increased exponentially with each increase in the stage of fibrosis: stage 1, MRR = 1.41 (95% CI 0.17-11.95); stage 2, MRR = 9.57 (95% CI 1.67-54.93); stage 3, MRR = 16.69 (95% CI 2.92-95.36); and stage 4, MRR = 42.30 (95% CI 3.51-510.34). Limitations of the study include an inability to adjust for comorbid conditions or demographics known to impact fibrosis progression in NAFLD and the inclusion of patients with simple steatosis and nonalcoholic steatohepatitis without fibrosis in the reference comparison group.

CONCLUSION

The risk of liver-related mortality increases exponentially with increase in fibrosis stage; these data have important implications in assessing the utility of each stage and benefits of regression of fibrosis from one stage to another. (Hepatology 2017;65:1557-1565).

De Novo and Recurrence of Nonalcoholic Steatohepatitis After Liver Transplantation

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in developing countries. Approximately 25% of patients with NAFLD develop nonalcoholic steatohepatitis (NASH). NASH-related cirrhosis is now a leading listing indication for liver transplantation in the United States. Although posttransplant survival for NASH-related cirrhosis is comparable with that of other liver diseases, many patients have features of metabolic syndrome, which can contribute to a recurrence of NAFLD or NASH. This article reviews the epidemiology, pathophysiology, and treatment of de novo and recurrence of NASH after liver transplantation.

Targeting the mitochondrial pyruvate carrier attenuates fibrosis in a mouse model of nonalcoholic steatohepatitis

Diseases of the liver related to metabolic syndrome have emerged as the most common and undertreated hepatic ailments. The cause of nonalcoholic fatty liver disease is the aberrant accumulation of lipid in hepatocytes, though the mechanisms whereby this leads to hepatocyte dysfunction, death, and hepatic fibrosis are still unclear. Insulin-sensitizing thiazolidinediones have shown efficacy in treating nonalcoholic steatohepatitis (NASH), but their widespread use is constrained by dose-limiting side effects thought to be due to activation of the peroxisome proliferator-activated receptor γ. We sought to determine whether a next-generation thiazolidinedione with markedly diminished ability to activate peroxisome proliferator-activated receptor γ (MSDC-0602) would retain its efficacy for treating NASH in a rodent model. We also determined whether some or all of these beneficial effects would be mediated through an inhibitory interaction with the mitochondrial pyruvate carrier 2 (MPC2), which was recently identified as a mitochondrial binding site for thiazolidinediones, including MSDC-0602. We found that MSDC-0602 prevented and reversed liver fibrosis and suppressed expression of markers of stellate cell activation in livers of mice fed a diet rich in trans-fatty acids, fructose, and cholesterol. Moreover, mice with liver-specific deletion of MPC2 were protected from development of NASH on this diet. Finally, MSDC-0602 directly reduced hepatic stellate cell activation in vitro, and MSDC-0602 treatment or hepatocyte MPC2 deletion also limited stellate cell activation indirectly by affecting secretion of exosomes from hepatocytes.

CONCLUSION

Collectively, these data demonstrate the effectiveness of MSDC-0602 for attenuating NASH in a rodent model and suggest that targeting hepatic MPC2 may be an effective strategy for pharmacologic development. (Hepatology 2017;65:1543-1556).

Hepatocellular carcinoma in non-alcoholic steatohepatitis: Current knowledge and implications for management

With the prevalence of hepatitis C virus expected to decline, the proportion of hepatocellular carcinoma (HCC) related to non-alcoholic steatohepatitis (NASH) is anticipated to increase exponentially due to the growing epidemic of obesity and diabetes. The annual incidence rate of developing HCC in patients with NASH-related cirrhosis is not clearly understood with rates ranging from 2.6%-12.8%. While multiple new mechanisms have been implicated in the development of HCC in NASH; further prospective long-term studies are needed to validate these findings. Recent evidence has shown a significant proportion of patients with non-alcoholic fatty liver disease and NASH progress to HCC in the absence of cirrhosis. Liver resection and transplantation represent curative therapeutic options in select NASH-related HCC patients but have placed a significant burden to our healthcare resources and utilization. Currently NASH-related HCC is the fastest growing indication for liver transplant in HCC candidates. Increased efforts to implement effective screening and preventative strategies, particularly in non-cirrhotic NASH patients, are needed to reduce the future impact imposed by NASH-related HCC.

A randomised controlled trial of losartan as an anti-fibrotic agent in non-alcoholic steatohepatitis

Introduction

Non-alcoholic fatty liver disease (NAFLD) is a common liver disease worldwide. Experimental and small clinical trials have demonstrated that angiotensin II blockers (ARB) may be anti-fibrotic in the liver. The aim of this randomised controlled trial was to assess whether treatment with Losartan for 96 weeks slowed, halted or reversed the progression of fibrosis in patients with non-alcoholic steatohepatitis (NASH).

Methods

Double-blind randomised-controlled trial of Losartan 50 mg once a day versus placebo for 96 weeks in patients with histological evidence of NASH. The primary outcome for the study was change in histological fibrosis stage from pre-treatment to end-of-treatment.

Results

The study planned to recruit 214 patients. However, recruitment was slower than expected, and after 45 patients were randomised (median age 55; 56% male; 60% diabetic; median fibrosis stage 2), enrolment was suspended. Thirty-two patients (15 losartan and 17 placebo) completed follow up period: one patient (6.7%) treated with losartan and 4 patients (23.5%) in the placebo group were “responders” (lower fibrosis stage at follow up compared with baseline). The major reason for slow recruitment was that 39% of potentially eligible patients were already taking an ARB or angiotensin converting enzyme inhibitor (ACEI), and 15% were taking other prohibited medications.

Conclusions

Due to the widespread use of ACEI and ARB in patients with NASH this trial failed to recruit sufficient patients to determine whether losartan has anti-fibrotic effects in the liver.

Trial registration

ISRCTN 57849521

Nonobese Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) refers to a group of conditions characterized by hepatic steatosis in the absence of significant alcohol consumption. NAFLD is seen commonly in patients with metabolic abnormalities associated with obesity, such as type II diabetes, dyslipidemia, and metabolic syndrome. Evidently, however, not all obese subjects develop NAFLD and, more importantly, NAFLD can be found in nonobese individuals. Although NAFLD occurring in nonobese subjects has been reported in children and adults of all ethnicities, it appears to be recognized more frequently in Asians, even when strict ethnicity-specific body mass index criteria are used to define obesity. Studies based on liver biopsies suggest that the prevalence of nonalcoholic steatohepatitis and fibrosis does not differ significantly between nonobese NAFLD and NAFLD in obese patients. Visceral obesity as opposed to general obesity, high fructose and cholesterol intake, and genetic risk factors (eg, palatin-like phospholipase domain-containing 3) may be associated with nonobese NAFLD. In general, nonalcoholic steatohepatitis is associated with increased mortality, primarily from cardiovascular causes, independent of other metabolic factors. Although data regarding the mortality impact of nonobese NAFLD are not as mature, it may be important to identify high-risk nonobese NAFLD patients and manage their metabolic profile. Currently, lifestyle modification to reduce visceral adiposity, including dietary changes and physical activity, remains the standard of care in patients with nonobese NAFLD.

A multi-component classifier for nonalcoholic fatty liver disease (NAFLD) based on genomic, proteomic, and phenomic data domains

Non-alcoholic fatty liver disease (NAFLD) represents a spectrum of conditions that include steatohepatitis and fibrosis that are thought to emanate from hepatic steatosis. Few robust biomarkers or diagnostic tests have been developed for hepatic steatosis in the setting of obesity. We have developed a multi-component classifier for hepatic steatosis comprised of phenotypic, genomic, and proteomic variables using data from 576 adults with extreme obesity who underwent bariatric surgery and intra-operative liver biopsy. Using a 443 patient training set, protein biomarker discovery was performed using the highly multiplexed SOMAscan^® proteomic assay, a set of 19 clinical variables, and the steatosis predisposing PNPLA3 rs738409 single nucleotide polymorphism genotype status. The most stable markers were selected using a stability selection algorithm with a L₁-regularized logistic regression kernel and were then fitted with logistic regression models to classify steatosis, that were then tested against a 133 sample blinded verification set. The highest area under the ROC curve (AUC) for steatosis of PNPLA3 rs738409 genotype, 8 proteins, or 19 phenotypic variables was 0.913, whereas the final classifier that included variables from all three domains had an AUC of 0.935. These data indicate that multi-domain modeling has better predictive power than comprehensive analysis of variables from a single domain.

Histological parameters and alcohol abstinence determine long-term prognosis in patients with alcoholic liver disease

BACKGROUND & AIMS

Few data exist on predictors of long-term prognosis in patients with alcoholic liver disease (ALD). Most studies have only assessed short-term prognosis in patients with advanced ALD. We aimed to assess the prognostic impact of clinical, biochemical and histological parameters on long-term prognosis in patients with early/compensated and decompensated ALD.

METHODS

Consecutive patients (n=192) with biopsy-proven liver disease due to alcohol abuse were analyzed retrospectively. Prognostic factors were evaluated in patients with early/compensated ALD (n=60) and in patients with decompensated ALD (clinical decompensation and/or bilirubin >3mg/dl at entry) (n=132). Factors that predict long-term survival were identified using Cox regression models.

RESULTS

Liver-related mortality at 5years was 13% in early/compensated and 43% in decompensated ALD. In early/compensated ALD patients, long-term prognosis was determined by fibrosis stage, but not by clinical or biochemical variables. Severe fibrosis (F3/4) was present in 52% and had a major impact on 10-year mortality (F3/4: 45% vs. F0-2: 0%, p<0.001). In contrast, in decompensated patients, a combination of clinical features (sex), biochemical markers of liver failure (bilirubin, international normalized ratio [INR]), and histological features (pericellular fibrosis) predicted long-term survival. During follow-up, abstinence from alcohol was an important predictor of survival in both early/compensated and decompensated ALD.

CONCLUSION

Fibrosis stage is the main predictor of long-term survival in patients with early/compensated ALD, while clinical, biochemical and histological parameters predict survival in patients with decompensated disease. Promoting abstinence may improve survival in patients with both early and advanced ALD.

LAY SUMMARY

In this study, we evaluated long-term outcome in 192 patients with alcoholic liver disease who underwent liver biopsy: 60 patients with early disease (no symptoms) and 132 patients with advanced disease (jaundice, complications of cirrhosis). Importantly, half of the patients with 'early' disease already had severe fibrosis or cirrhosis on liver histology and dismal outcome (45% mortality at 10years). Abstinence from alcohol improved the prognosis in both early and advanced stages of the disease.

Nonalcoholic fatty liver disease-related cirrhosis is commonly unrecognized and associated with hepatocellular carcinoma

Determination of cirrhosis in nonalcoholic fatty liver disease (NAFLD) is important as it alters prognosis and management. We aimed to examine whether cirrhosis was diagnosed incidentally or intentionally in patients with NAFLD. We reviewed 100 patients with NAFLD cirrhosis to determine mode of cirrhosis diagnosis (incidental or by intent), severity of liver disease at diagnosis, diagnostician, and previous clinical imaging or laboratory evidence of unrecognized cirrhosis. The majority (66/100) of patients with NAFLD cirrhosis were diagnosed incidentally, with the majority of these (74%) diagnosed with NAFLD simultaneously. Those with incidental cirrhosis diagnoses had more deranged platelet and international normalized ratio levels (P < 0.05) and were more likely to have concomitant hepatocellular carcinoma (HCC) (12% versus 0%, P < 0.05). Incidental cirrhosis was diagnosed following imaging (32%) or liver tests (26%) performed for reasons unrelated to liver disease, following unexpected endoscopic finding of varices (21%) or an unexpected surgical finding (14%). Diagnoses by intent were predominantly made by gastroenterologists/hepatologists, whereas general practitioners, surgeons, and physicians tended to diagnose cirrhosis incidentally (P < 0.001). The majority of patients diagnosed incidentally (n = 48/66, 73%) had previous thrombocytopenia, splenomegaly, or high noninvasive fibrosis scores. Following diagnosis, patients diagnosed incidentally were less likely to undergo HCC screening. Conclusion: The majority of patients with NAFLD cirrhosis are diagnosed incidentally. These patients are more likely to have advanced liver disease and HCC. Increased awareness of screening for cirrhosis is needed in patients with NAFLD. (Hepatology Communications 2017;1:53–60)

Esculetin ameliorates hepatic fibrosis in high fat diet induced non-alcoholic fatty liver disease by regulation of FoxO1 mediated pathway

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD), a chronic metabolic disorder is associated with oxidative stress, inflammation and fibrotic cascades. In this study, we aimed to examine the effects of Esculetin, a well-known anti-oxidant on TGF-β1 mediated liver fibrosis and FoxO1 activity.

METHODS

A non-genetic murine model for NAFLD was developed by chronic high fat diet (HFD) (58% calories from fats) feeding in Wistar rats. The plasma biochemical parameters, liver function tests, oxidative stress, and histopathological alterations were assessed. The alterations in extracellular matrix (ECM) deposition and FoxO1 activity were assessed by immunohistochemistry.

RESULTS

The aberrations in plasma parameters, liver functioning, morphometric and microscopic changes in liver structure of HFD fed rats were significantly improved by treatment with Esculetin. Liver fibrosis, identified in the form of collagen deposition and expression of fibrotic proteins like TGF-β1 and fibronectin was also markedly controlled by Esculetin. The expression of phospho-FoxO1 was found to be reduced in HFD fed rats' liver, showing an increase in activation of FoxO1 under insulin resistant and hyperglycemic states. Esculetin treatment could improve phospho-FoxO1 expression, thus showing its ability to act on Akt/PI3K/FoxO1 pathway.

CONCLUSIONS

As per the previous studies, a potential therapy for NAFLD may be the one with multi-faceted actions on insulin resistance, oxidative stress, inflammation and fibrosis. This study demonstrates the efficiency of Esculetin in improving liver fibrosis in HFD induced NAFLD.

Noninvasive markers for staging fibrosis in chronic delta hepatitis

BACKGROUND

Serum fibrosis markers are useful in staging chronic hepatitis B (HBV) and C (HCV) virus but have not been evaluated in chronic hepatitis D virus (HDV).

AIM

To evaluate the utility of serum fibrosis markers [fibrosis-4 score (FIB-4), aspartate aminotransferase (AST) to alanine aminotransferase (ALT) ratio, aspartate aminotransferase ratio (AAR), age-platelet index (API), AST-to-platelet-ratio-index (APRI) and Hui score] in HDV infection.

METHODS

Clinical and histologic laboratory data from HBV, HCV and HDV patients were evaluated and serum fibrosis markers were calculated. The ability of fibrosis markers to detect advanced fibrosis (Ishak ≥4) and cirrhosis (Ishak = 6) were evaluated and compared between viral infections.

RESULTS

A total of 1003 subjects (HCV = 701, HBV = 240 and HDV = 62) with mean age of 46 ± 11 and 66% male were evaluated. HDV subjects had higher ALT and AST than HCV and lower platelets than both HBV and HCV. Histologically, HDV had the greatest percentage of Ishak ≥4 and necroinflammation. FIB-4 performed best in detecting advanced fibrosis and cirrhosis in all viral cohorts. In HDV, area under the receiver operator curve (AUROC) 95% confidence intervals for detecting advanced fibrosis were: FIB-4 = 0.70 (0.55-0.84), API = 0.69 (0.55-0.82), APRI = 0.68 (0.54-0.82), Hui score = 0.63 (0.49-0.78), AAR = 0.63 (0.48-0.77). The AUROC for detecting cirrhosis in HDV were: FIB-4 = 0.83 (0.69-0.97), API = 0.80 (0.66-0.95), APRI = 0.75 (0.61-0.89), Hui score = 0.70 (0.49-0.91) and AAR = 0.70 (0.48-0.93). Adjustment of published cut-offs led to marginal improvements in FIB4 for advanced fibrosis and of APRI for cirrhosis in HDV.

CONCLUSIONS

Serum fibrosis markers have lower performance accuracy in chronic HDV infected patients compared to HBV and HCV patients. Other noninvasive fibrosis markers should be explored to assist in the management of these patients.

Pathological Findings of NASH and NAFLD: for Guidebook of NASH and NAFLD, 2015: The Japan Society of Hepatology

Nonalcoholic fatty liver disease (NAFLD) is an increasingly common chronic liver disease worldwide. NAFLD comprises a variety of clinical and histopathological changes that can be broadly divided into nonalcoholic fatty liver (NAFL, simple steatosis) and nonalcoholic steatohepatitis (NASH). The differential diagnosis between NAFL and NASH is important because NASH is a more advanced form. This diagnosis therefore determines the prognosis and therapeutic management. At present the interpretation of NASH is made based on the histopathological features of steatohepatitis, i.e. 'steatosis', 'lobular inflammation', hepatocyte 'ballooning, 'Mallory-Denk bodies' and 'fibrosis'. Here, we summarize the pathological findings guidelines for NASH as it was already published in 2015 in Japanese in the clinical guidebook organized by the Japan Society of Hepatology.

Pathology of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) covers a spectrum of lesions ranging from steatosis (Non-alcoholic Fatty Liver or NAFL) to a complex pattern with hepatocellular injury and inflammation (non-alcoholic steatohepatitis; NASH) in the absence of alcohol intake. However, it is increasingly clear that intermediate patterns may exist. The histopathological evaluation of liver biopsy samples is central in the diagnosis of NAFLD and NASH in the absence of sufficiently accurate non-invasive tests because a precise definition of each group is a key issue. When at least 5% of hepatocytes display steatosis, patients can be defined as having NAFLD in an appropriate clinical context. When, in addition, lobular inflammation and liver cell clarification/ballooning are present, then the lesion is usually defined as NASH. Evaluation of the stage of fibrosis is even more fundamental than necroinflammation since it is the main prognostic factor of this disease. Semi-quantitative histological scoring systems have been proposed for NAFLD, but they are not useful in clinical practice and each has certain limitations. For comprehensive purposes, we suggest describing histopathological lesions in NAFLD using the SAF (Steatosis, Activity, Fibrosis) score which assesses separately the grade of steatosis (S, from S0 to S3), the grade of activity (A from A0 to A4 by adding grades of ballooning and lobular inflammation, both from 0 to 2) and the stage of fibrosis (F from F0 to F4).

Improvement in liver histology due to lifestyle modification is independently associated with improved kidney function in patients with non-alcoholic steatohepatitis

BACKGROUND

Several recent studies have shown a strong association between non-alcoholic steatohepatitis (NASH) and chronic kidney disease.

AIM

To examine the relationship between changes in liver histology and renal function in patients with NASH.

METHODS

The present analysis represents a post hoc analysis of a recently published trial that included 261 patients with NASH who were treated with lifestyle modifications during 52 weeks. Kidney function was evaluated through Chronic Kidney Disease Epidemiology Collaboration estimated glomerular filtration rates (eGFR, mL/min/1.73 m² ) overtime. We explored correlations between the kidney function and improvement in histological outcomes at 52 weeks.

RESULTS

Interestingly, a one-stage reduction in fibrosis (r = 0.20, P < 0.01) and resolution of NASH (r = 0.17, P < 0.01) were significantly correlated with an improvement in the kidney function. The eGFR values significantly increased in patients with fibrosis improvement (+7.6 ± 6.5 mL/min/1.73 m² ), compared to those without fibrosis improvement (-1.98 ± 6.4 mL/min/1.73 m² ) (P < 0.01) at end of treatment (EOT). Likewise, NASH resolution was associated with an increase in eGFR compared with patients without NASH resolution (2.32 ± 7.8 mL/min/1.73 m² vs. -1.04 ± 5.9 mL/min/1.73 m² , P = 0.04) at EOT. After controlling for the confounders, the association between fibrosis improvement, NASH resolution and eGFR change remained significant (P < 0.05 for both).

CONCLUSIONS

Improvement in liver histology due to lifestyle modification is independently associated with improved kidney function in NASH. As new drugs for NASH emerge, studies should address whether improvement in histology in response to pharmacotherapies yield the same improvement in kidney function as weight loss.

Pediatric Non-alcoholic Fatty Liver Disease

Childhood obesity has reached epidemic proportions, and by 2012, more than one third of American children were overweight or obese. As a result, increasingly, children are developing complications of obesity including liver disease. In fact, non-alcoholic fatty liver disease is the most common form of chronic liver disease seen in children today. Recently, there has been a burgeoning literature examining the pathogenesis, genetic markers, and role of the microbiome in this disease. On the clinical front, new modalities of diagnosing hepatic steatosis and hepatic fibrosis are being developed to provide non-invasive methods of surveillance in children. Lastly, the mainstay of treatment of pediatric non-alcoholic fatty liver disease (NAFLD) has been largely through lifestyle interventions, namely, dieting and exercise. Currently, there are a number of clinical trials examining novel lifestyle and drug therapies for NAFLD that are registered with the US National Institutes of Health ClinicalTrials.gov website.

Docosahexanoic Acid Plus Vitamin D Treatment Improves Features of NAFLD in Children with Serum Vitamin D Deficiency: Results from a Single Centre Trial

BACKGROUND

There are no licensed treatments for non alcoholic fatty liver disease (NAFLD) in adults or children. In NAFLD, several studies have shown a benefit of omega-3 fatty acid treatment on lipid profile, insulin-sensitivity and hepatic steatosis and it has also been suggested that Vitamin D treatment has potential antifibrotic properties in liver disease.

TRIAL DESIGN

To date, however, there are no studies that have tested the combination of Docosahexanoic acid (DHA) and vitamin D treatment which may benefit the whole spectrum of disease in NAFLD. Our aim therefore, was to test the effect of daily DHA (500 mg) plus vitamin D (800 IU) treatment, in obese children with biopsy-proven NAFLD and vitamin D deficiency, in a randomized, double-blind placebo-controlled trial.

METHODS

The 41/43 patients completed the study (18-treatment, 23-placebo). At 12 months: i) the main outcome was liver histology improvement, defined by NAS; ii) the secondary outcome was amelioration of metabolic parameters.

RESULTS

DHA plus vitamin D treatment reduced the NAFLD Activity Score (NAS), in the treatment group (5.4 v1.92; p<0.001 for baseline versus end of study). There was no change in fibrosis score, but a reduction of the activation of hepatic stellate cells (HSC) and fibrillar collagen content was noted (3.51±1.66 v. 1.59±1.37; p = 0.003) in treatment group. Moreover, the triglycerides (174.5 vs. 102.15 mg/dl), ALT (40.25 vs. 24.5 UI/l) and HOMA-IR (4.59 vs. 3.42) were all decreased with treatment.

CONCLUSION

DHA plus vitamin D treatment improved insulin-resistance, lipid profile, ALT and NAS. There was also decreased HSC activation and collagen content with treatment.

Role of NCAN rs2228603 polymorphism in the incidence of nonalcoholic fatty liver disease: a case-control study

BACKGROUND

Recently genome-wide association studies identified that NCAN rs2228603 polymorphism was associated with non-alcoholic fatty liver disease (NAFLD) mainly in subjects of European ancestry. While no research have been conducted to demonstrate the relationship between NCAN rs2228603 and NAFLD in Chinese Han adults. The aim of this study was to investigate whether NCAN rs2228603 is associated with NAFLD in Chinese population.

METHODS

Gene NCAN rs2228603 was genotyped in 182 patients with NAFLD and 195 healthy controls. The expression of NCAN was tested according to polymerase chain reaction analysis (PCR) and serum lipids were performed by biology techniques.

RESULTS

No significant difference was found in genotype and allele frequencies of NCAN rs2228603 between the NAFLD group and the controls (P > 0.05). Subjects with the NCAN rs2228603 CT genotype showed a higher level of alkaline phosphatase (AKP) (P = 0.017) and a higher high-density lipoprotein (HDL) (P < 0.05).

CONCLUSIONS

Our study for the first time identified that the gene NCAN rs2228603 is not a risk factor for the incidence of NAFLD in Chinese population. Also we found the dual and opposite role of T variant in protecting liver with a higher level of HDL and conferring risk for liver damage with a higher level of AKP.

TRIAL REGISTRATION

Chinese Clinical Trial Register.gov Identifier: ChiCTR-ROC-15006447 .

The economic and clinical burden of nonalcoholic fatty liver disease in the United States and Europe

Nonalcoholic fatty liver disease (NAFLD) is a major cause of chronic liver disease. There is uncertainty around the economic burden of NAFLD. We constructed a steady-state prevalence model to quantify this burden in the United States and Europe. Five models were constructed to estimate the burden of NAFLD in the United States and four European countries. Models were built using a series of interlinked Markov chains, each representing age increments of the NAFLD and the general populations. Incidence and remission rates were calculated by calibrating against real-world prevalence rates. The data were validated using a computerized disease model called DisMod II. NAFLD patients transitioned between nine health states (nonalcoholic fatty liver, nonalcoholic steatohepatitis [NASH], NASH-fibrosis, NASH-compensated cirrhosis, NASH-decompensated cirrhosis, hepatocellular carcinoma, liver transplantation, post-liver transplant, and death). Transition probabilities were sourced from the literature and calibrated against real-world data. Utilities were obtained from NAFLD patients using the Short Form-6D. Costs were sourced from the literature and local fee schedules. In the United States, over 64 million people are projected to have NAFLD, with annual direct medical costs of about $103 billion ($1,613 per patient). In the Europe-4 countries (Germany, France, Italy, and United Kingdom), there are ∼52 million people with NAFLD with an annual cost of about €35 billion (from €354 to €1,163 per patient). Costs are highest in patients aged 45-65. The burden is significantly higher when societal costs are included.

CONCLUSION

The analysis quantifies the enormity of the clinical and economic burdens of NAFLD, which will likely increase as the incidence of NAFLD continues to rise. (Hepatology 2016;64:1577-1586).

The independent predictors of non-alcoholic steatohepatitis and its individual histological features.: Insulin resistance, serum uric acid, metabolic syndrome, alanine aminotransferase and serum total cholesterol are a clue to pathogenesis and candidate targets for treatment

AIM

The diagnosis of non-alcoholic steatohepatitis (NASH) is based on the individual histological features: steatosis, lobular inflammation and ballooning. Non-alcoholic fatty liver disease (NAFLD) activity score (NAS ≥ 5) is used in clinical trials. Fibrosis dictates long-term NAFLD prognosis. Recently, more-than-mild portal inflammation has raised interest as a marker of NAFLD severity. We assessed the independent predictors of: (I) individual histological lesions of NASH; (II) diagnosis of NASH; (III) significant (stage ≥2) and advanced (stage ≥3) fibrosis; and (IV) more-than-mild portal inflammation.

METHODS

Data from 118 consecutive biopsy-proven NAFLD patients observed at our institution were retrospectively analyzed.

RESULTS

At stepwise multivariate logistic regression analyses, independent predictors were as follows. For the individual histological features of NASH: insulin resistance (IR), assessed with Homeostasis Model Assessment-IR (HOMA-IR), serum uric acid (SUA) and serum total cholesterol (TCH) for moderate-to-severe steatosis; waist circumference (waist), HOMA-IR and TCH for lobular inflammation; waist, HOMA-IR, metabolic syndrome (MS), serum alanine aminotransferase (ALT), SUA and TCH for ballooning. For NASH diagnosis: waist, HOMA-IR, MS, ALT, SUA and TCH (Brunt et al.'s classification); ALT, SUA and TCH for NAS ≥ 5. For significant and advanced fibrosis, respectively: waist, MS and ALT; age, platelets, HOMA-IR, diabetes and TCH. For more-than-mild portal inflammation: serum aspartate aminotransferase (AST), serum iron, NAS ≥ 5 and significant liver fibrosis.

CONCLUSION

HOMA-IR, SUA, MS, ALT and TCH are independent predictors of NASH and its individual histological lesions, notably including fibrosis. Based on our findings, these factors should be considered major pathogenic drivers of NASH and, by inference, potential targets for treatment.

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.

The role of mitochondrial genomics in patients with non-alcoholic steatohepatitis (NASH)

Background

Visceral obesity and metabolic syndrome are commonly associated with non-alcoholic fatty liver disease (NAFLD). The progression of steatosis to NASH depends on a number of metabolic and patient-related factors. The mechanisms of genetic predisposition towards the development of NASH and related fibrosis remain unclear. In this study, our aim was to utilize mitotyping and identify mitochondrial haplotypes that may be associated with NAFLD.

Methods

We examined mitochondrial haplotypes along with patatin-like phospholipase domain containing 3 (PNPLA3) rs738409 genotype to determine their association with NAFLD phenotypes. Whole blood samples were obtained from 341 patients (BMI > 35) undergoing weight reduction surgery after written consent. Liver biopsies were centrally reviewed by a single pathologist based on predetermined pathologic protocol (41.9 % Non-NASH NAFLD, 30.4 % NASH, 27.5 % controls). A 1,122 bp of the mitochondrial control loop was sequenced for each sample and classified into haplogroups.

Results

The presence of haplogroup L exhibits protection against the development of NASH and pericellular fibrosis. The alleles of PNPLA3 locus showed differential distribution in cohorts with NAFLD, NASH and pericellular fibrosis. Heterozygosity at this locus is independently associated with higher risk of having NASH and pericellular fibrosis.

Conclusion

Mitochondrial genetics play an important role in NASH probably by modulation of oxidative stress and the efficiency of oxidative phosphorylation.

Electronic supplementary material

The online version of this article (doi:10.1186/s12881-016-0324-0) contains supplementary material, which is available to authorized users.

Diagnostic accuracy and prognostic significance of blood fibrosis tests and liver stiffness measurement by FibroScan in non-alcoholic fatty liver disease

BACKGROUND & AIMS

NAFLD is highly prevalent but only a small subset of patients develop advanced liver fibrosis with impaired liver-related prognosis. We aimed to compare blood fibrosis tests and liver stiffness measurement (LSM) by FibroScan for the diagnosis of liver fibrosis and the evaluation of prognosis in NAFLD.

METHODS

Diagnostic accuracy was evaluated in a cross-sectional study including 452 NAFLD patients with liver biopsy (NASH-CRN fibrosis stage), LSM, and eight blood fibrosis tests (BARD, NAFLD fibrosis score, FibroMeter(NAFLD), aspartate aminotransferase to platelet ratio index (APRI), FIB4, FibroTest, Hepascore, FibroMeter(V2G)). Prognostic accuracy was evaluated in a longitudinal study including 360 NAFLD patients.

RESULTS

LSM and FibroMeter(V2G) were the two best-performing tests in the cross-sectional study: AUROCs for advanced fibrosis (F3/4) were, respectively, 0.831±0.019 and 0.817±0.020 (p⩽0.041 vs. other tests); rates of patients with ⩾90% negative/positive predictive values for F3/4 were 56.4% and 46.7% (p<0.001 vs. other tests); Obuchowski indexes were 0.834±0.014 and 0.798±0.016 (p⩽0.036 vs. other tests). Two fibrosis classifications were developed to precisely estimate the histological fibrosis stage from LSM or FibroMeter(V2G) results without liver biopsy (diagnostic accuracy, respectively: 80.8% vs. 77.4%, p=0.190). Kaplan-Meier curves in the longitudinal study showed that both classifications categorised NAFLD patients into subgroups with significantly different prognoses (p<0.001): the higher was the class of the fibrosis classification, the worse was the prognosis.

CONCLUSIONS

LSM and FibroMeter(V2G) were the most accurate of nine evaluated tests for the non-invasive diagnosis of liver fibrosis in NAFLD. LSM and FibroMeter(V2G) fibrosis classifications help physicians estimate both fibrosis stage and patient prognosis in clinical practice.

LAY SUMMARY

The amount of liver fibrosis is the main determinant of the liver-related prognosis in patients with non-alcoholic fatty liver disease (NAFLD). We evaluated eight blood tests and FibroScan in a cross-sectional diagnostic study and found that FibroScan and the blood test FibroMeter(V2G) were the two most accurate tests for the non-invasive evaluation of liver fibrosis in NAFLD. A longitudinal prognostic study showed these two tests initially developed for the diagnosis are also prognostic markers as they allow for the stratification of NAFLD patients in several subgroups with significantly different prognosis.

Transient elastography and APRI score: looking at false positives and false negatives. Diagnostic performance and association to fibrosis staging in chronic hepatitis C

Although long regarded as the gold standard for liver fibrosis staging in chronic hepatitis C (CHC), liver biopsy (LB) implies both the risk of an invasive procedure and significant variability. The aim of this study was to evaluate the diagnostic performance for transient elastography (TE) and aspartate aminotransferase to platelet index (APRI) used alone and in combination compared to liver biopsy and to analyze false positive/negative results. Patients with CHC, and no previous clinical diagnosis of cirrhosis were enrolled to undergo liver biopsy, TE and APRI. A total of 182 adult patients with a median age of 55 years and median body mass index of 26.71 kg/m² were analyzed. On LB, 56% of patients had significant levels of fibrosis (METAVIR F≥2) and 28% had advanced fibrosis (F3/F4). The strongest performance for both tests was observed for exclusion of advanced fibrosis with good negative predictive values (89 and 86%, respectively). Low necroinflammatory activity on LB was associated with false negative TE. False positives were associated with NASH and smaller LB fragments. Correlation between APRI and Fibroscan for F≥2 was 100% and 84% for F≥3 and remained high in both false negative and false positive instances, correctly identifying F<2 in 71% of cases and F<3 in 78% (and potentially foregoing up to 84% of LB). We concluded that low individual performance indicators could be attributable to limitations of LB. Poorer differentiation of lower levels of fibrosis is a known issue for LB and remains so for noninvasive tests. Good predictability is possible, however, for advanced fibrosis.

Epidemiology and natural history of non-alcoholic fatty liver disease

Non-alcoholic steatohepatitis (NASH) is part of the spectrum of non-alcoholic fatty liver disease (NAFLD) that leads to progressive liver disease and presents a growing challenge to public health. Because of the increased prevalence of metabolic syndrome and obesity, NAFLD and NASH have expanded to a substantial extent. In NASH patients, advanced fibrosis is the major predictor of morbidity and liver-related mortality, and an accurate diagnosis of NASH is mandatory. Although there is currently no validated test of serum biomarkers available to diagnose NASH, and histologic evaluation with a liver biopsy remains the gold standard, screening for fibrosis is recommended in patients with suspicion of NASH. Clinical prediction models and serum biomarkers for advanced fibrosis have relatively good negative predictive value and can be useful for screening. Also, transient elastography is increasingly available to estimate fibrosis in NASH. Therefore, due to the lack of a reliable and accepted non-invasive diagnostic modality, screening for NASH in the general population is not currently recommended. Better understanding of the natural history of NASH is needed to evaluate the utility and cost-effectiveness of screening.

Global epidemiology of nonalcoholic fatty liver disease-Meta-analytic assessment of prevalence, incidence, and outcomes

Nonalcoholic fatty liver disease (NAFLD) is a major cause of liver disease worldwide. We estimated the global prevalence, incidence, progression, and outcomes of NAFLD and nonalcoholic steatohepatitis (NASH). PubMed/MEDLINE were searched from 1989 to 2015 for terms involving epidemiology and progression of NAFLD. Exclusions included selected groups (studies that exclusively enrolled morbidly obese or diabetics or pediatric) and no data on alcohol consumption or other liver diseases. Incidence of hepatocellular carcinoma (HCC), cirrhosis, overall mortality, and liver-related mortality were determined. NASH required histological diagnosis. All studies were reviewed by three independent investigators. Analysis was stratified by region, diagnostic technique, biopsy indication, and study population. We used random-effects models to provide point estimates (95% confidence interval [CI]) of prevalence, incidence, mortality and incidence rate ratios, and metaregression with subgroup analysis to account for heterogeneity. Of 729 studies, 86 were included with a sample size of 8,515,431 from 22 countries. Global prevalence of NAFLD is 25.24% (95% CI: 22.10-28.65) with highest prevalence in the Middle East and South America and lowest in Africa. Metabolic comorbidities associated with NAFLD included obesity (51.34%; 95% CI: 41.38-61.20), type 2 diabetes (22.51%; 95% CI: 17.92-27.89), hyperlipidemia (69.16%; 95% CI: 49.91-83.46%), hypertension (39.34%; 95% CI: 33.15-45.88), and metabolic syndrome (42.54%; 95% CI: 30.06-56.05). Fibrosis progression proportion, and mean annual rate of progression in NASH were 40.76% (95% CI: 34.69-47.13) and 0.09 (95% CI: 0.06-0.12). HCC incidence among NAFLD patients was 0.44 per 1,000 person-years (range, 0.29-0.66). Liver-specific mortality and overall mortality among NAFLD and NASH were 0.77 per 1,000 (range, 0.33-1.77) and 11.77 per 1,000 person-years (range, 7.10-19.53) and 15.44 per 1,000 (range, 11.72-20.34) and 25.56 per 1,000 person-years (range, 6.29-103.80). Incidence risk ratios for liver-specific and overall mortality for NAFLD were 1.94 (range, 1.28-2.92) and 1.05 (range, 0.70-1.56).

CONCLUSIONS

As the global epidemic of obesity fuels metabolic conditions, the clinical and economic burden of NAFLD will become enormous. (Hepatology 2016;64:73-84).

The Relationship between Type 2 Diabetes Mellitus and Non-Alcoholic Fatty Liver Disease Measured by Controlled Attenuation Parameter

PURPOSE

The severity of non-alcoholic fatty liver disease (NAFLD) in type 2 diabetes mellitus (T2DM) population compared with that in normal glucose tolerance (NGT) individuals has not yet been quantitatively assessed. We investigated the prevalence and the severity of NAFLD in a T2DM population using controlled attenuation parameter (CAP).

MATERIALS AND METHODS

Subjects who underwent testing for biomarkers related to T2DM and CAP using Fibroscan® during a regular health check-up were enrolled. CAP values of 250 dB/m and 300 dB/m were selected as the cutoffs for the presence of NAFLD and for moderate to severe NAFLD, respectively. Biomarkers related to T2DM included fasting glucose/insulin, fasting C-peptide, hemoglobin A1c (HbA1c), glycoalbumin, and homeostasis model assessment of insulin resistance of insulin resistance (HOMA-IR).

RESULTS

Among 340 study participants (T2DM, n=66; pre-diabetes, n=202; NGT, n=72), the proportion of subjects with NAFLD increased according to the glucose tolerance status (31.9% in NGT; 47.0% in pre-diabetes; 57.6% in T2DM). The median CAP value was significantly higher in subjects with T2DM (265 dB/m) than in those with pre-diabetes (245 dB/m) or NGT (231 dB/m) (all p<0.05). Logistic regression analysis showed that subjects with moderate to severe NAFLD had a 2.8-fold (odds ratio) higher risk of having T2DM than those without NAFLD (p=0.02; 95% confidence interval, 1.21-6.64), and positive correlations between the CAP value and HOMA-IR (ρ0.407) or fasting C-peptide (ρ0.402) were demonstrated.

CONCLUSION

Subjects with T2DM had a higher prevalence of severe NAFLD than those with NGT. Increased hepatic steatosis was significantly associated with the presence of T2DM, and insulin resistance induced by hepatic fat may be an important mechanistic connection.

Biopsy and Noninvasive Methods to Assess Progression of Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) comprises a spectrum of histopathologic features, ranging from isolated hepatic steatosis, to steatohepatitis with evidence of hepatocellular injury and fibrosis, to cirrhosis. The diagnosis and determination of NAFLD prognosis requires clinical and histopathologic assessments. Liver biopsy still is regarded as the reference for differentiating steatosis (NAFL) from nonalcoholic steatohepatitis, for staging hepatic fibrosis, and for identifying NAFLD in patients with other chronic liver disease. Standardized grading and staging histologic scoring systems, such as the NAFLD activity score and the steatosis, activity, and fibrosis score, can help guide clinical decisions and assess outcomes of clinical trials. Improved understanding of the pathophysiology of NAFLD and technologic advances have led to algorithms that can be used to assess serum biomarkers and imaging methods that are noninvasive alternatives to biopsy collection and analysis. We review the advantages and limitations of biopsy analysis and noninvasive tests as diagnostic and prognostic tools for patients with NAFLD. We also discuss techniques to improve dynamic histopathology assessment, and emerging blood and imaging biomarkers of fibrogenesis.

Contribution of Alcoholic and Nonalcoholic Fatty Liver Disease to the Burden of Liver-Related Morbidity and Mortality

Nonalcoholic fatty liver disease (NAFLD) and alcoholic liver disease (ALD) are common causes of chronic liver disease. NAFLD is associated with obesity and metabolic syndrome whereas ALD is associated with excessive alcohol consumption. Both diseases can progress to cirrhosis, hepatocellular carcinoma, and liver-related death. A higher proportion of patients with NAFLD die from cardiovascular disorders than patients with ALD, whereas a higher proportion of patients with ALD die from liver disease. NAFLD and ALD each are associated with significant morbidity, impairment to health-related quality of life, and economic costs to society.

Liver Transplantation for Alcoholic and Nonalcoholic Fatty Liver Disease: Pretransplant Selection and Posttransplant Management

Alcoholic fatty liver disease (ALD) and nonalcoholic fatty liver disease (NAFLD) are common causes of chronic liver disease throughout the world. Although they have similar histologic features, a diagnosis of NAFLD requires the absence of significant alcohol use. ALD is seen commonly in patients with a long-standing history of excessive alcohol use, whereas NAFLD is encountered commonly in patients who have developed complications of obesity, such as insulin resistance, hypertension, and dyslipidemia. Lifestyle contributes to the development and progression of both diseases. Although alcohol abstinence can cause regression of ALD, and weight loss can cause regression of NAFLD, many patients with these diseases develop cirrhosis. ALD and NAFLD account for nearly 30% of liver transplants performed in the United States. Patients receiving liver transplants for ALD or NAFLD have similar survival times as patients receiving transplants for other liver disorders. Although ALD and NAFLD recur frequently after liver transplantation, graft loss from disease recurrence after transplantation is uncommon. Cardiovascular disease and de novo malignancy are leading causes of long-term mortality in liver transplant recipients with ALD or NAFLD.

The Natural Course of Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent form of chronic liver disease in the world, paralleling the epidemic of obesity and Type 2 diabetes mellitus (T2DM). NAFLD exhibits a histological spectrum, ranging from “bland steatosis” to the more aggressive necro-inflammatory form, non-alcoholic steatohepatitis (NASH) which may accumulate fibrosis to result in cirrhosis. Emerging data suggests fibrosis, rather than NASH per se, to be the most important histological predictor of liver and non-liver related death. Nevertheless, only a small proportion of individuals develop cirrhosis, however the large proportion of the population affected by NAFLD has led to predictions that NAFLD will become a leading cause of end stage liver disease, hepatocellular carcinoma (HCC), and indication for liver transplantation. HCC may arise in non-cirrhotic liver in the setting of NAFLD and is associated with the presence of the metabolic syndrome (MetS) and male gender. The MetS and its components also play a key role in the histological progression of NAFLD, however other genetic and environmental factors may also influence the natural history. The importance of NAFLD in terms of overall survival extends beyond the liver where cardiovascular disease and malignancy represents additional important causes of death.

Insulin resistance in development and progression of nonalcoholic fatty liver disease

Although insulin resistance (IR) is strongly associated with nonalcoholic fatty liver disease (NAFLD), the association of IR and NAFLD is not universal and correlation between IR and severity of NAFLD is still controversial. In this review, we summarize recent evidence that partially dissociates insulin resistance from NAFLD. It has also been reported that single-nucleotide polymorphisms in the diacylglycerol acyltransferase gene, rather than IR, account for the variability in liver fat content. Polymorphisms of the patatin-like phospholipase 3 gene have also been reported to be associated with NAFLD without metabolic syndrome, which suggests that genetic conditions that promote the development of fatty changes in the liver may occur independently of IR. Moreover, environmental factors such as nutrition and physical activity as well as small intestinal bacterial overgrowth have been linked to the pathogenesis of NAFLD, although some of the data are conflicting. Therefore, findings from both genetically engineered animal models and humans with genetic conditions, as well as recent studies that have explored the role of environmental factors, have confirmed the view that NAFLD is a polygenic disease process caused by both genetic and environmental factors. Therefore, IR is not the sole predictor of the pathogenesis of NAFLD.

Novel Pharmacotherapy Options for NASH

While simple to recommend, diet and lifestyle measures as a first-line therapy for nonalcoholic steatohepatitis (NASH) are hardly a model of successful therapy, as most clinicians can testify. They can be complex to implement, hard to sustain, and of limited efficacy in advanced stages of the disease. The need for specific pharmacotherapy is now acknowledged by practitioners, the pharmaceutical industry, and regulators and is largely expected by patients. The result is a clear move away from products developed second hand for NASH (such as pioglitazone or metformin) or from generic, non-specific hepatoprotectors (such as pentoxifylline, ursodeoxycholic acid, or antioxidants) toward molecules developed and tested specifically for NASH that aim to correct one or several of the pathways of liver injury in this disease. The two most advanced molecules, obeticholic acid and elafibranor, have shown encouraging data on improving hepatic histology. Both compounds appear to clear NASH, with obeticholic acid improving liver fibrosis and elafibranor improving the glycemic and lipid profile. Much larger trials, currently ongoing, will need to confirm these preliminary data and better characterize the safety and tolerability profile. Meanwhile, other compounds are being tested, a few in phase 2b studies (cenicriviroc, aramchol for NASH, and simtuzumab for NASH fibrosis) and many more in earlier, smaller trials. Most of these drug candidates target different pathways, which speaks to the diversity and dynamism of the NASH pipeline.

Histological Assessment of NAFLD

Nonalcoholic fatty liver disease (NAFLD) covers a spectrum of histological lesions ranging from steatosis to a complex pattern with hepatocyte injury and inflammation in an appropriate clinical context. The disease has been artificially dichotomized into NAFL (steatosis) and NASH (steatosis with hepatocellular injury and inflammation), but it is increasingly clear that intermediate patterns may exist. More than NASH, the stage of fibrosis was shown to govern prognosis, and for such evaluation, a liver biopsy of adequate size and width is needed. Like for any other chronic liver diseases, semi-quantitative histologic scores have been proposed. They are not useful in clinical practice but concur to categorize homogeneous group of patients according to their histology. Pediatric NAFLD is a growing concern. While a subgroup of children may harbor different but characteristic histological patterns, most of them display a mixed pattern or features similar to the adults. Today, liver histology is the mainstay for clinical trials. Biopsy is used both for enrollment and for assessing benefit of clinical trials. End points such as reversion of NASH or regression of fibrosis are acceptable but require a clear histological definition.

Elafibranor, an Agonist of the Peroxisome Proliferator-Activated Receptor-α and -δ, Induces Resolution of Nonalcoholic Steatohepatitis Without Fibrosis Worsening

BACKGROUND & AIMS

Elafibranor is an agonist of the peroxisome proliferator-activated receptor-α and peroxisome proliferator-activated receptor-δ. Elafibranor improves insulin sensitivity, glucose homeostasis, and lipid metabolism and reduces inflammation. We assessed the safety and efficacy of elafibranor in an international, randomized, double-blind placebo-controlled trial of patients with nonalcoholic steatohepatitis (NASH).

METHODS

Patients with NASH without cirrhosis were randomly assigned to groups given elafibranor 80 mg (n = 93), elafibranor 120 mg (n = 91), or placebo (n = 92) each day for 52 weeks at sites in Europe and the United States. Clinical and laboratory evaluations were performed every 2 months during this 1-year period. Liver biopsies were then collected and patients were assessed 3 months later. The primary outcome was resolution of NASH without fibrosis worsening, using protocol-defined and modified definitions. Data from the groups given the different doses of elafibranor were compared with those from the placebo group using step-down logistic regression, adjusting for baseline nonalcoholic fatty liver disease activity score.

RESULTS

In intention-to-treat analysis, there was no significant difference between the elafibranor and placebo groups in the protocol-defined primary outcome. However, NASH resolved without fibrosis worsening in a higher proportion of patients in the 120-mg elafibranor group vs the placebo group (19% vs 12%; odds ratio = 2.31; 95% confidence interval: 1.02-5.24; P = .045), based on a post-hoc analysis for the modified definition. In post-hoc analyses of patients with nonalcoholic fatty liver disease activity score ≥4 (n = 234), elafibranor 120 mg resolved NASH in larger proportions of patients than placebo based on the protocol definition (20% vs 11%; odds ratio = 3.16; 95% confidence interval: 1.22-8.13; P = .018) and the modified definitions (19% vs 9%; odds ratio = 3.52; 95% confidence interval: 1.32-9.40; P = .013). Patients with NASH resolution after receiving elafibranor 120 mg had reduced liver fibrosis stages compared with those without NASH resolution (mean reduction of 0.65 ± 0.61 in responders for the primary outcome vs an increase of 0.10 ± 0.98 in nonresponders; P < .001). Liver enzymes, lipids, glucose profiles, and markers of systemic inflammation were significantly reduced in the elafibranor 120-mg group vs the placebo group. Elafibranor was well tolerated and did not cause weight gain or cardiac events, but did produce a mild, reversible increase in serum creatinine (effect size vs placebo: increase of 4.31 ± 1.19 μmol/L; P < .001).

CONCLUSIONS

A post-hoc analysis of data from trial of patients with NASH showed that elafibranor (120 mg/d for 1 year) resolved NASH without fibrosis worsening, based on a modified definition, in the intention-to-treat analysis and in patients with moderate or severe NASH. However, the predefined end point was not met in the intention to treat population. Elafibranor was well tolerated and improved patients' cardiometabolic risk profile. ClinicalTrials.gov number: NCT01694849.