Validation of the BARD scoring system in Polish patients with nonalcoholic fatty liver disease (NAFLD)

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].

Clinical Link between the BARD Score at Diagnosis and Mortality during Follow-Up in Patients with Antineutrophil Cytoplasmic Antibody-Associated Vasculitis

This study investigated whether the BARD score at diagnosis could predict all-cause mortality in patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV). This study included 236 immunosuppressive drug-naïve patients without chronic liver diseases such as viral hepatitis, non-alcoholic fatty liver disease (NAFLD), and advanced liver diseases and their clinical data at diagnosis, such as age, sex, and the Birmingham Vasculitis Activity Score (BVAS). The BARD score was calculated by the sum of aspartate transaminase (AST)/alanine transaminase (ALT) ratio ≥ 0.8 (+2 points), body mass index (BMI) ≥ 28 kg/m2 (+1 point), and the presence of type 2 diabetes mellitus (T2DM) (+1 point). All-cause mortality was investigated as a poor outcome of AAV. The median age of AAV patients was 60.0 years, and 34.7% were men. Among AAV patients, 7, 50, and 187 scored 1, 1, and 2 points owing to having a BMI ≥ 28 kg/m2, T2DM, and an AST/ALT ratio ≥ 0.8, respectively. Patients with a BARD score ≥ 2 and those with a BARD score ≥ 3 exhibited significantly lower cumulative patient survival rates than those without (p = 0.038 and p = 0.003, respectively). In the multivariable Cox analysis, among the two cut-offs of the BARD scores, only a BARD score ≥ 3 (HR 2.866), along with age (HR 1.061), male sex (HR 2.327), and BVAS (HR 1.100), was independently associated with all-cause mortality during follow-up. In conclusion, this study was the first to demonstrate that the BARD score ≥ 3 at AAV diagnosis could predict all-cause mortality during follow-up in AAV patients.

Determination of the Level of Cardiovascular Risk in 172,282 Spanish Working Women

Introduction, objectives: Although cardiovascular events have been traditionally associated mainly with men, some data reflect an increase in women, which may even exceed their male counterparts, constituting the leading cause of death in working women in Spain. The objective of this present study was to analyze the level of cardiovascular risk in Spanish working women by assessing the influence of age, type of work, and tobacco consumption.

MATERIAL, METHODS

A descriptive cross-sectional study was carried out in 172,282 working women from different Spanish geographical areas and from different companies between January 2018 and June 2020. A range of variables and risk factors were assessed and various cardiovascular risk scales were used to analyze the data.

RESULTS

An increase in cardiovascular risk was observed in the least qualified work groups, mainly corresponding to blue-collar workers, when using the SCORE or REGICOR risk equation. The prevalence of altered values for all the parameters analyzed (overweight and obesity, hypertension, dyslipidemia, diabetes, fatty liver, hepatic fibrosis, atherogenic indexes, and cardiovascular risk scales) was higher among blue-collar women. Age was the only factor that influenced all the cardiovascular risk scales studied, increasing risk when comparing the group of women aged 50 years and older with the others.

CONCLUSIONS

Aging and belonging to the blue-collar job category meant worse results in the cardiovascular risk scales and in all the parameters analyzed. This is in line with numerous studies that argue that age and zip code are more influential than genetic code.

Associations of non-invasive indices of liver steatosis and fibrosis with progressive kidney impairment in adults with type 2 diabetes

AIMS

Longitudinal data linking non-alcoholic fatty liver disease to kidney dysfunction in type 2 diabetes (T2D) are limited. This study evaluated the associations of non-invasive indices of liver steatosis and liver fibrosis with kidney impairment, and the mediatory role of the pro-angiogenic factor leucine-rich α-2 glycoprotein 1 (LRG1).

METHODS

T2D adults (n = 2057) were followed for a mean period of 6.1 ± 1.6 years. Baseline liver steatosis [(hepatic steatosis index (HSI) and Zhejiang University index (ZJU)] and liver fibrosis [aspartate transaminase/alanine transaminase ratio (AAR) and BARD] indices derived from composite scoring systems were calculated. Plasma LRG1 levels were quantified using immunoassay. The study outcomes were progressive kidney function decline defined as estimated glomerular filtration rate (eGFR) decline of ≥ 40% and albuminuria progression defined as an increase in albuminuria category.

RESULTS

Cross-sectionally, liver steatosis and liver fibrosis indices were associated with increased albuminuria (urinary albumin/creatinine ratio ≥ 30 µg/mg) and reduced renal function (eGFR < 60 mL/min/1.73 m²) after covariate adjustment, respectively. Approximately 32% of the participants experienced progressive kidney function decline, while 38% had albuminuria worsening over time. Longitudinal analysis revealed that baseline AAR (hazard ratio: 1.56; 95% CI 1.15-2.11) and BARD (hazard ratio: 1.16, 95% CI 1.04-1.28) predicted progressive kidney function decline, partly mediated by LRG1. In contrast, liver steatosis (HSI and ZJU) but not liver fibrosis (AAR and BARD) indices were independently associated with albuminuria progression.

CONCLUSIONS

Increased liver steatosis scores were associated with albuminuria deterioration. Conversely, liver fibrosis indices may be associated with progressive kidney function decline, potentially driven by increased inflammation and angiogenesis.

The Link between NAFLD and Metabolic Syndrome

Metabolic syndrome (MetS) is characterized by an association of cardiovascular and diabetes mellitus type 2 risk factors. Although the definition of MetS slightly differs depending on the society that described it, its central diagnostic criteria include impaired fasting glucose, low HDL-cholesterol, elevated triglycerides levels and high blood pressure. Insulin resistance (IR) is believed to be the main cause of MetS and is connected to the level of visceral or intra-abdominal adipose tissue, which could be assessed either by calculating body mass index or by measuring waist circumference. Most recent studies revealed that IR may also be present in non-obese patients, and considered visceral adiposity to be the main effector of MetS' pathology. Visceral adiposity is strongly linked with hepatic fatty infiltration also known as non-alcoholic fatty liver disease (NAFLD), therefore, the level of fatty acids in the hepatic parenchyma is indirectly linked with MetS, being both a cause and a consequence of this syndrome. Taking into consideration the present pandemic of obesity and its tendency to drift towards a progressively earlier onset due to the Western lifestyle, it leads to an increased NAFLD incidence. Novel therapeutic resources are lifestyle intervention with physical activity, Mediterranean diet, or therapeutic surgical respective metabolic and bariatric surgery or drugs such as SGLT-2i, GLP-1 Ra or vitamin E. NAFLD early diagnosis is important due to its easily available diagnostic tools such as non-invasive tools: clinical and laboratory variables (serum biomarkers): AST to platelet ratio index, fibrosis-4, NAFLD Fibrosis Score, BARD Score, fibro test, enhanced liver fibrosis; imaging-based biomarkers: Controlled attenuation parameter, magnetic resonance imaging proton-density fat fraction, transient elastography (TE) or vibration controlled TE, acoustic radiation force impulse imaging, shear wave elastography, magnetic resonance elastography; and the possibility to prevent its complications, respectively, fibrosis, hepato-cellular carcinoma or liver cirrhosis which can develop into end-stage liver disease.

Diagnostic accuracy of blood biomarkers and non-invasive scores for the diagnosis of NAFLD and NASH: Systematic review and meta-analysis

INTRODUCTION AND OBJECTIVES

Fatty liver disease is an important public health problem. Early diagnosis is critical to lower its rate of progression to irreversible/terminal stages. This study aimed to evaluate the accuracy of non-invasive prediction scores for fatty liver disease (NAFLD and NASH) diagnosis in adults.

MATERIALS AND METHODS

A search was conducted in 10 databases, a qualitative synthesis of 45 studies, and quantitative analysis of the six most common scores. There were 23 risk scores found for NAFLD diagnosis and 32 for NASH diagnosis. The most used were Fatty Liver Index (FLI), aspartate aminotransferase (AST) to Platelet Ratio Index, Fibrosis-4 Index (FIB-4), AST/alanine aminotransferase (ALT) ratio, BARD score, and NAFLD fibrosis score (NFS).

RESULTS

The results from the meta-analysis for FLI: Area under the curve (AUC) of 0.76 (95% Confidence Interval [CI] 0.73, 0.80), sensitivity 0.67 (CI 95% 0.62, 0.72) and specificity 0.78 (CI 95% 0.74, 0.83). The AST to Platelet Ratio Index: AUC 0.83 (CI 95% 0.80, 0.86), sensitivity 0.45 (95% CI 0.29, 0.62), and specificity of 0.89 (95% CI 0.83, 0.92). The NFS: AUC of 0.82 (CI 95% 0.78, 0.85), sensitivity 0.30 (CI 95% 0.27, 0.33) and specificity 0.96 (CI 95% 0.95,0.96).

CONCLUSIONS

The FLI for NAFLD and AST to Platelet Ratio Index for NASH were the risk scores with the highest prognostic value in the included studies. Further research is needed for the application of new diagnostic risk scores for NAFLD and NASH.

Determination of cardiovascular risk in Spanish veterinarians using different scaling methods

Introduction

Cardiovascular diseases are responsible for a significant morbimortality rate around the world. Due to the characteristics of their work, health care professionals, including veterinarians, are more prone to present this type of pathology.

Objectives

To determine the level of cardiovascular risk using different scales in a group of veterinarians.

Methods

A descriptive and cross-sectional study of 610 Spanish veterinarians was conducted to assess cardiovascular risk scores, including 14 overweight and obesity scales, six fatty liver scales, six cardiovascular risk scales, four atherogenic indices, and three metabolic syndrome scales.

Results

The prevalence of obesity among women was 7.95%, and 17.53% among men. Hypertension was present in 15.23% of women and 24.68% of men. Dyslipidemia affected 45% of women and 58.64% of men. The prevalence of metabolic syndrome according to the International Diabetes Federation criteria was slightly over 10% while 10.90% of women and 14.93% of men showed moderate to high values on the Registre Gironí del Cor scale.

Conclusions

There is a moderate to high level of cardiovascular risk among veterinarians in this group.

Obesidad, hábitos de vida y valoración FLI en la población laboral española durante la pandemia

Antecedentes: el hígado graso no alcohólico es la enfermedad hepática más común en el mundo, habitualmente asintomática y manifestación hepática del síndrome metabólico. Objetivo: estimar el riesgo de hígado graso mediante el índice de hígado graso (FLI, Fatty Liver Index) y su relación con el índice de masa corporal (IMC), indicadores de adiposidad, hábitos de vida y variables sociodemográficas. Material y métodos: estudio descriptivo transversal realizado con 815 trabajadores de entre 18-66 años, durante la vigilancia de la salud de las empresas participantes, desde marzo de 2020 hasta junio de 2021. Se utiliza la calculadora FLI y se establecen relaciones con variables sociodemográficas, índices de adiposidad, hábitos de alimentación y actividad física con el uso de los cuestionarios PREDIMED e IPAQ. Resultados: el FLI > 60 se relaciona significativamente con el IMC, el perímetro de la cintura y el índice cintura-cadera. El IMC incrementa el riesgo casi 20 veces (odds ratio 19,87; IC 95% 10,84-36,44) de sufrir la enfermedad. Los valores altos son más perjudiciales en hombres y el riesgo aumenta con la edad. Un FLI en rango medio/alto (> 30) muestra una relación significativa con la adherencia a MedDiet y con la actividad física realizada, con diferencias entre géneros (p < 0,0001). Conclusión: el riesgo de hígado graso aumenta con la obesidad y con los hábitos de vida no saludables, con valores más desfavorables entre los hombres. Destaca la importancia de valorar, junto con el IMC, los indicadores de adiposidad. Palabras clave: hígado graso, enfermedad del hígado graso no alcohólico, obesidad, salud laboral.

Obesidad, hábitos de vida y valoración FLI en la población laboral española durante la pandemia

Antecedentes: el hígado graso no alcohólico es la enfermedad hepática más común en el mundo, habitualmente asintomática y manifestación hepática del síndrome metabólico. Objetivo: estimar el riesgo de hígado graso mediante el índice de hígado graso (FLI, Fatty Liver Index) y su relación con el índice de masa corporal (IMC), indicadores de adiposidad, hábitos de vida y variables sociodemográficas. Material y métodos: estudio descriptivo transversal realizado con 815 trabajadores de entre 18-66 años, durante la vigilancia de la salud de las empresas participantes, desde marzo de 2020 hasta junio de 2021. Se utiliza la calculadora FLI y se establecen relaciones con variables sociodemográficas, índices de adiposidad, hábitos de alimentación y actividad física con el uso de los cuestionarios PREDIMED e IPAQ. Resultados: el FLI > 60 se relaciona significativamente con el IMC, el perímetro de la cintura y el índice cintura-cadera. El IMC incrementa el riesgo casi 20 veces (odds ratio 19,87; IC 95% 10,84-36,44) de sufrir la enfermedad. Los valores altos son más perjudiciales en hombres y el riesgo aumenta con la edad. Un FLI en rango medio/alto (> 30) muestra una relación significativa con la adherencia a MedDiet y con la actividad física realizada, con diferencias entre géneros (p < 0,0001). Conclusión: el riesgo de hígado graso aumenta con la obesidad y con los hábitos de vida no saludables, con valores más desfavorables entre los hombres. Destaca la importancia de valorar, junto con el IMC, los indicadores de adiposidad. Palabras clave: hígado graso, enfermedad del hígado graso no alcohólico, obesidad, salud laboral.

Advances in fibrosis biomarkers in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) affects a quarter of the adult world population and the degree of liver fibrosis represents the best predictor of the development of liver-related outcomes. Easily applicable and well performing non-invasive fibrosis tests can overcome the limitations of liver biopsy and are of paramount importance to identify at-risk subjects in clinical practice. While tests with optimal performance and ease of use do not exist at this stage, available markers can be divided in three broad groups: simple serum tests, complex serum tests and elastographic methods. Simple scores (such as Fibrosis-4 and NAFLD Fibrosis Score) are based on readily available biochemical data and clinical features, while complex/proprietary tests (such as Fibrotest, Enhanced Liver Fibrosis and Hepascore) directly measure markers of fibrogenesis and fibrolysis, but have higher costs. Elastography techniques estimate the degree of fibrosis from liver stiffness and are based on either ultrasound or magnetic resonance (MR) imaging. MR elastography has better performance compared with sonographic techniques and is not affected by obesity and inflammation, but is highly costly and less available. In general, non-invasive tests are able to exclude the presence of fibrosis, but their positive predictive value is low to moderate and they lead to a high number of indeterminate results. In this context, a combination of different tests might increase accuracy while reducing gray-zone results. Their ability to predict future events and response to treatment is suboptimal and needs to be studied further. Finally, recent studies have tried different approaches, spanning from "omics" to the microbiome and micro-RNAs, with some promising results.

Current Options and Future Directions for NAFLD and NASH Treatment

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide, with a broad spectrum ranging from simple steatosis to advanced stage of nonalcoholic steatohepatitis (NASH). Although there are many undergoing clinical trials for NAFLD treatment, there is no currently approved treatment. NAFLD accounts as a major causing factor for the development of hepatocellular carcinoma (HCC), and its incidence rises accompanying the prevalence of obesity and diabetes. Reprogramming of antidiabetic and anti-obesity medicine is a major treatment option for NAFLD and NASH. Liver inflammation and cellular death, with or without fibrosis account for the progression of NAFLD to NASH. Therefore, molecules and signaling pathways involved in hepatic inflammation, fibrosis, and cell death are critically important targets for the therapy of NAFLD and NASH. In addition, the avoidance of aberrant infiltration of inflammatory cytokines by treating with CCR antagonists also provides a therapeutic option. Currently, there is an increasing number of pre-clinical and clinical trials undergoing to evaluate the effects of antidiabetic and anti-obesity drugs, antibiotics, pan-caspase inhibitors, CCR2/5 antagonists, and others on NAFLD, NASH, and liver fibrosis. Non-invasive serum diagnostic markers are developed for fulfilling the need of diagnostic testing in a large amount of NAFLD cases. Overall, a better understanding of the underlying mechanism of the pathogenesis of NAFLD is helpful to choose an optimized treatment.

Body weight variability and the risk of cardiovascular outcomes in patients with nonalcoholic fatty liver disease

We investigated the association between body weight variability and the risks of cardiovascular disease and mortality in patients with nonalcoholic fatty liver disease (NAFLD) using large-scale, nationwide cohort data. We included 726,736 individuals with NAFLD who underwent a health examination between 2009 and 2010. NAFLD was defined as a fatty liver index ≥ 60, after excluding significant alcohol intake, viral hepatitis, and liver cirrhosis. Body weight variability was assessed using four indices, including variability independent of the mean (VIM). During a median 8.1-year follow-up, we documented 11,358, 14,714, and 22,164 cases of myocardial infarction (MI), stroke, and all-cause mortality, respectively. Body weight variability was associated with an increased risk of MI, stroke, and mortality after adjusting for confounding variables. The hazard ratios (HRs) (95% confidence intervals) for the highest quartile, compared with the lowest quartile, of VIM for body weight were 1.15 (1.10-1.20), 1.22 (1.18-1.26), and 1.56 (1.53-1.62) for MI, stroke, and all-cause mortality, respectively. Body weight variability was associated with increased risks of MI, stroke, and all-cause mortality in NAFLD patients. Appropriate interventions to maintain a stable weight could positively affect health outcomes in NAFLD patients.

Predictive scoring system for advanced liver fibrosis in Japanese patients with severe obesity

PURPOSE

The aim of this study was to examine the predictive scoring system of advanced liver fibrosis in severely obese Japanese patients.

METHODS

Seventy-two patients underwent laparoscopic sleeve gastrectomy and intraoperative liver biopsies. We classified these patients into two groups: Brunt stage ≥ 2 (advanced fibrosis) and 0/1 (none/mild fibrosis). A logistic regression analysis was performed to identify the predictors of advanced fibrosis.

RESULTS

Sixteen patients had advanced fibrosis, while 56 had no/mild fibrosis. The prevalence of type 2 diabetes mellitus (T2DM) in advanced fibrosis group was significantly higher than in none/mild fibrosis. An univariate analysis of the factors predicting advanced fibrosis showed significant differences in AST/ALT ratio, serum insulin levels, HOMA-IR, and type IV collagen 7S in the T2DM group. According to a multivariate analysis, type IV collagen 7S was an independent predictor and the cutoff value was 5.6 ng/mL. We created a flow chart; high risk (T2DM and type IV collagen 7S ≥ 5.6 ng/mL), moderate risk (T2DM and type IV collagen 7S < 5.6 ng/mL), and low risk (non-DM). For those at high risk, the sensitivity, specificity, positive predictive value, and negative predictive value were 56.2%, 94.4%, 75.0%, and 87.9%, respectively.

CONCLUSION

This classification system has the potential to accurately categorize the risk of liver fibrosis.

Noninvasive diagnosis of fibrosis in non-alcoholic fatty liver disease: diagnostic accuracy of different scores

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a spectrum of pathologies characterized by liver damage without history of excessive alcohol intake. Advanced fibrosis, generally detected by transient elastography (TE), is the most significant predictor of poor prognosis and mortality among these patients. This study aimed at assessing the accuracy of five noninvasive methods, compared to TE, for the evaluation of severity of liver fibrosis in patients with NAFLD.

METHODS

The cohort included 41 patients, in whom the result of TE was compared to AST/ALT ratio, BARD Score (Body Mass Index, AST/ALT ratio, diabetes), AST To Platelet Ratio Index (APRI), Fibrosis-4 Index (FIB-4 Index) and NAFLD Fibrosis Score (NFS).

RESULTS

The severity of fibrosis, assessed by TE, was the following: F0 (absence of fibrosis): 17%, F1 (mild): 39%, F2 (moderate): 17%, F3 (advanced): 10%, F4 (cirrhosis): 17%. Performances of the diagnostic scores were: 49% for AST/ALT ratio, 68% for BARD Score, 73% for APRI, 59% and 71% for the lower and upper cut-off of FIB-4 Index, 61% and 76% for the lower and upper cut-off of NFS.

CONCLUSIONS

Considering the scores compared to TE, AST/ALT ratio was not enough sensitive, while BARD Score had better diagnostic performance and APRI had a superior accuracy than the formers. However, FIB-4 and NFS were the most useful tests and their performance could be improved through the use of a single cut-off. These findings demonstrated that the most accurate scores, compared to TE, were NFS and FIB-4.

Liver Fibrosis Assessment in a Cohort of Greek HIV Mono-Infected Patients by Non-Invasive Biomarkers

BACKGROUND

Non-alcoholic Fatty Liver Disease (NAFLD) is common in HIV-infected individuals. Liver biopsy remains the gold-standard procedure for the diagnosis of liver fibrosis, but both Transient Elastography (TE) and Non-invasive Biomarkers (NIBMs) have emerged as alternatives.

OBJECTIVES

Our study's aim was to validate commonly used NIBMs for the assessment of liver fibrosis in a cohort of Greek HIV-mono-infected patients.

METHODS

Inclusion criteria were confirmed HIV-infection and age>18 years and exclusion criteria HBV or HCV seropositivity, liver disease other than NAFLD, alcohol abuse, ascites, transaminases levels>4xULN(upper limit of normal) and Body-Mass index(BMI)>40. Liver stiffness (LS) measurement with TE and thorough laboratory work up and medical history were acquired at study entry. FIB-4, APRI, NFS, BARD, Forns and Lok scores were calculated for each patient.

RESULTS

A total of 157 patients were eligible for this study. Significant liver fibrosis, compatible with Metavir score of F3-F4, was found in only 11(7%) patients. These findings were in accordance with those of the NIBMs; the BARD score constituting the only exception, allocating 102(65%) patients as having significant liver fibrosis. In order to obtain a balance between sensitivity and specificity new cut-offs for each NIBM were calculated; FIB-4 score yielded the best results, since by changing the cut-off to 1.49 a sensitivity and specificity balanced for both close to 85% was achieved.

CONCLUSION

Our findings suggest that NIBMs can be used for the evaluation of liver fibrosis in HIV mono-infected patients. New cut-offs for NIBMs should probably be calculated, to help distinguishing patients with significant from those with mild/no fibrosis.

Applying Non-Invasive Fibrosis Measurements in NAFLD/NASH: Progress to Date

Nonalcoholic fatty liver disease (NAFLD) has now become a worldwide health issue due to the obesity epidemic, affecting approximately 90% of the obese population and 15-40% of the general population. It is the most common form of chronic liver disease in the United States. NAFLD constitutes a spectrum of diseases ranging in severity from mild, such as fatty liver, progressing into nonalcoholic steatohepatitis (NASH), then fibrosis, and ending with cirrhosis. NASH and increasing fibrosis stage are associated with increased morbidity and mortality; the fibrosis stage is therefore a critical element of risk stratification needed to determine therapeutic approach and also the response to treatment. Liver biopsy is considered the 'gold standard' in the diagnosis of NAFLD. However, it is not practical for widespread clinical use because it is invasive, costly, and associated with complications including occasional death. These limitations have driven the development of noninvasive tests that can accurately predict the fibrosis stage in those with NAFLD. In this review, we provide a concise overview of different non-invasive measurements used for NAFLD/NASH.

Noninvasive indices for predicting nonalcoholic fatty liver disease in patients with chronic kidney disease

BACKGROUND

Data on clinical characteristics of nonalcoholic fatty liver disease (NAFLD) in patients with chronic kidney disease (CKD) are scarce. We investigated the clinical features and risk factors of NAFLD using noninvasive serum markers in CKD patients and attempted the temporal validation of a predictive model for CKD based on NAFLD.

METHODS

This retrospective cross-sectional study was conducted in a single tertiary center. We enrolled 819 CKD patients and evaluated the predictive performance of relevant clinical and laboratory markers for the presence of NAFLD in both derivation (data from 2011 to 2014, n = 567) and validation (data from 2015 to 2016, n = 252) groups.

RESULTS

In the derivation group, NAFLD was observed in 89 patients (15.7%; mean body mass index (BMI), 24.6 kg/m2; median estimated glomerular filtration rate (eGFR), 28.0 ml/min). BMI, hemoglobin, serum alanine aminotransferase, eGFR, and triglyceride-glucose index were used to derive a prediction model for the presence of NAFLD. Using the cutoff value of 0.146, the area under the receiver operating characteristic curve (AUROC) for the prediction of NAFLD was 0.850. In the validation group, NAFLD was observed in 51 patients (20.2%; mean BMI, 25.4 kg/m2; median eGFR, 36.0 ml/min). Using the same prediction model and cutoff value, the AUROC was 0.842. NAFLD prevalence in CKD patients was comparable to that in the general population, increasing over time.

CONCLUSIONS

Our model using BMI, renal function, triglyceride-glucose index, serum alanine aminotransferase, and hemoglobin accurately predicted the presence of NAFLD in CKD patients.

Is endocan a novel potential biomarker of liver steatosis and fibrosis?

Background

Studies that evaluated endocan levels in nonalcoholic fatty liver disease (NAFLD) and liver fibrosis are scarce. We aimed to explore endocan levels in relation to different stages of liver diseases, such as NAFLD, as determined with fatty liver index (FLI) and liver fibrosis, as assessed with BARD score.

Methods

A total of 147 participants with FLI≥60 were compared with 64 participants with FLI <30. An FLI score was calculated using waist circumference, body mass index, gamma-glutamyl transferase and triglycerides. Patients with FLI≥60 were further divided into those with no/mild fibrosis (BARD score 0-1 point; n=23) and advanced fibrosis (BARD score 2-4 points; n=124). BARD score was calculated as follows: diabetes mellitus (1 point) + body mass index≥28 kg/m2 (1 point) + aspartate amino transferase/alanine aminotransferase ratio≥0.8 (2 points).

Results

Endocan was independent predictor for FLI and BARD score, both in univariate [OR=1.255 (95% CI= 1.104-1.426), P=0.001; OR=1.208 (95% CI=1.029-1.419), P=0.021, respectively] and multivariate binary logistic regression analysis [OR=1.287 (95% CI=1.055-1.570), P=0.013; OR=1.226 (95% CI=1.022-1.470), P=0.028, respectively]. Endocan as a single predictor showed poor discriminatory capability for steatosis/fibrosis [AUC=0.648; (95% CI=0.568-0.727), P=0.002; AUC= 0.667 (95% CI=0.555-0.778), P=0.013, respectively], whereas in a Model, endocan showed an excellent clinical accuracy [AUC=0.930; (95% CI=0.886-0.975), P<0.001, AUC=0.840 (95% CI=0.763-0.918), P<0.001, respectively].

Conclusions

Endocan independently correlated with both FLI and BARD score. However, when tested in models (with other biomarkers), endocan showed better discriminatory ability for liver steatosis/fibrosis, instead of its usage as a single biomarker.

The Association between SOCS1-1656G>A Polymorphism, Insulin Resistance and Obesity in Nonalcoholic Fatty Liver Disease (NAFLD) Patients

Suppressor of cytokine signaling (SOCS) proteins prevent uncontrolled cytokine signaling and appear to play a role in the pathological processes behind obesity and insulin resistance. The polymorphism of the SOCS1 gene (rs243330, −1656G>A) is associated with obesity and glucose sensitivity. To estimate the effect of this SOCS1 gene polymorphism on nonalcoholic fatty liver disease (NAFLD) susceptibility, we performed a study on 138 patients with ultrasound-confirmed NAFLD and 1000 healthy blood donors. The relationship between the SOCS1−1656G>A polymorphism and serum biochemical parameters in NAFLD was additionally investigated. The SOCS1 variant was genotyped using a dedicated TaqMan assay. The frequency of rs243330 polymorphism did not differ between patients and controls. However, in a cohort of obese individuals (BMI ≥ 30 kg/m²) the occurrence of the G allele of the SOCS1−1656G>A polymorphism was strongly associated with NAFLD (odds ratio (OR) 1.6; 95% CI,1.1–2.5; p = 0.009), and carriers of the AA genotype have lower risk of developing NAFLD (OR 0.4; 95% CI, 0.2–0.7; p = 0.004). Overweight NAFLD patients who were carriers of GG genotypes had significantly lower levels of homeostasis model assessment of insulin resistance (HOMA-IR) values (p = 0.03 vs. AA), and the obese GG homozygotes had lower serum concertation of triglyceride (GG vs. AA; p = 0.02). Serum liver enzyme activities were not modified by the presence of SOCS1 risk variants. In conclusion, the observed phenotype of overweight NAFLD patients with non-elevated levels of TG and HOMA-IR, which is associated with genetic variants of SOCS1, provides a rationale for further research on the pathophysiology of fatty liver disease.

Nonalcoholic Fatty Liver Disease: An Update on the Diagnosis

Nonalcoholic fatty liver disease (NAFLD) is a common liver disease and a major cause of related complications such as cirrhosis and hepatocellular carcinoma (HCC). NAFLD progresses through the stages of simple steatosis, nonalcoholic steatohepatitis (NASH), fibrosis, cirrhosis, and HCC. However, NAFLD usually cannot be diagnosed in a timely manner, which is largely attributed to the asymptomatic features of NAFLD patients and the lack of an effective and accurate noninvasive screening approach. Although liver biopsy has been recognized as a gold standard for diagnosing NAFLD, this approach is not suitable for screening and monitoring NAFLD because of its high cost and invasiveness. Several noninvasive screening and diagnostic systemic assessments have been developed in recent years for NAFLD evaluation. Here we summarize the current status and methods for NAFLD diagnosis, including both noninvasive (imaging, biomarkers) and invasive (liver biopsy) assessments. We further discuss the advantages and disadvantages of these developed diagnostic approaches for NAFLD.

Overview of the Pathogenesis, Genetic, and Non-Invasive Clinical, Biochemical, and Scoring Methods in the Assessment of NAFLD

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease worldwide. It represents a range of disorders, including simple steatosis, nonalcoholic steatohepatitis (NASH), and liver cirrhosis, and its prevalence continues to rise. In some cases, hepatocellular carcinoma (HCC) may develop. The develop;ment of non-invasive diagnostic and screening tools is needed, in order to reduce the frequency of liver biopsies. The most promising methods are those able to exclude advanced fibrosis and quantify steatosis. In this study, new perspective markers for inflammation, oxidative stress, apoptosis, and fibrogenesis; emerging scoring models for detecting hepatic steatosis and fibrosis; and new genetic, epigenetic, and multiomic studies are discussed. As isolated biochemical parameters are not specific or sensitive enough to predict the presence of NASH and fibrosis, there is a tendency to use various markers and combine them into mathematical algorithms. Several predictive models and scoring systems have been developed. Current data suggests that panels of markers (NAFLD fibrosis score, Fib-4 score, BARD score, and others) are useful diagnostic modalities to minimize the number of liver biopsies. The review unveils pathophysiological aspects related to new trends in current non-invasive biochemical, genetic, and scoring methods, and provides insight into their diagnostic accuracies and suitability in clinical practice.

Comparison of laboratory indices of non-alcoholic fatty liver disease for the detection of incipient kidney dysfunction

Non-alcoholic fatty liver disease (NAFLD) is closely linked to insulin resistance and related adverse health outcomes. We investigated the non-invasive index of NAFLD that has the best performance in estimating the renal manifestations of metabolic disturbances. This nation-wide, cross-sectional study included 11,836 subjects, using various non-invasive assessments comprising routinely measured clinical and laboratory variables. The subjects were native Koreans aged 20 years or older and had no diabetes, history of liver or kidney disease. All participants were divided into quintiles according to their fibrosis-4 (FIB-4) results. Participants in the highest quintile were more hypertensive and obese with greater glycemic exposure, poor lipid profiles, and impaired kidney function, than those in the other quintiles. Multiple logistic regression, adjusted for age, sex, smoking, systolic blood pressure, white blood cell, platelet, fasting plasma glucose, and triglyceride, demonstrated that FIB-4, the hepatic steatosis index, the aspartate aminotransferase/alanine aminotransferase (AST/ALT) ratio, Gholam’s model for non-alcoholic steatohepatitis, and the BARD score were independently associated with kidney dysfunction. ROC curve analysis revealed that FIB-4 (AUC = 0.6227, 95% CI [0.5929–0.6526], p = 0.0258) was the most precise in predicting kidney dysfunction. Our findings suggest that FIB-4 may be a favorable screening tool for the renal manifestation of hepatic metabolic disturbances.

Diagnostic and Treatment Implications of Nonalcoholic Fatty Liver Disease and Nonalcoholic Steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) affects 75 to 100 million adults in the United States and is the leading cause of chronic liver disease worldwide, fueled by the rising epidemic of obesity and metabolic syndrome. NAFLD is the hepatic manifestation of metabolic syndrome; thus, accurately assessing and managing comorbid metabolic syndrome components is paramount. Nonalcoholic steatohepatitis (NASH) is a subset of NAFLD that includes a more progressive and advanced form of the disease, with a greater risk of fibrosis progression. Correctly diagnosing and staging NAFLD and distinguishing the subset of NASH patients is not only critical for disease monitoring and prognostication, but also holds potential implications for therapies. Although the current therapeutic landscape for NAFLD does not offer many options, future therapies are on the horizon. Properly staging the severity of disease and fibrosis is especially important when considering the eligibility and cost-effectiveness of these therapies.

Branched chain amino acid transaminase 1 (BCAT1) is overexpressed and hypomethylated in patients with non-alcoholic fatty liver disease who experience adverse clinical events: A pilot study

Background and objectives

Although the burden of non-alcoholic fatty liver disease (NAFLD) continues to increase worldwide, genetic factors predicting progression to cirrhosis and decompensation in NAFLD remain poorly understood. We sought to determine whether gene expression profiling was associated with clinical decompensation and death in patients with NAFLD, and to assess whether altered DNA methylation contributes to these changes in gene expression.

Methods

We performed a retrospective analysis of 86 patients in the Duke NAFLD Clinical Database and Biorepository with biopsy-proven NAFLD whose liver tissue was previously evaluated for gene expression and DNA methylation using array based technologies. We assessed the prospective development of liver and cardiovascular disease related outcomes, including hepatic decompensation as identified by the development of ascites, hepatic encephalopathy, hepatocellular carcinoma, or variceal bleeding as well as stroke and myocardial infarction via medical chart review.

Results

Of the 86 patients, 47 had F0-F1 fibrosis and 39 had F3-F4 fibrosis at index liver biopsy. Gene expression probe sets (n = 54,675) were analyzed; 42 genes showed significant differential expression (p<0.05) and a two-fold change in expression between patients with and without any outcome. Two expression probes of the branched chain amino-acid transaminase 1 (BCAT1) gene were upregulated (p = 0.02; fold change 2.1 and 2.2 respectively) in patients with a clinical outcome. Methylation of three of the 34 BCAT1 CpG methylation probes were significantly inversely correlated with BCAT1 expression specific to the probes predictive of clinical deterioration.

Conclusion

We found differential gene expression, correlated to changes in DNA methylation, at multiple BCAT1 loci in patients with cardiovascular outcomes and/or hepatic decompensation. BCAT1 catalyzes the transformation of alpha-ketoglutarate to glutamate and has been linked to the presence and severity of NAFLD, possibly through derangements in the balance between glutamate and alpha-ketoglutarate. Given the potential for BCAT1 to identify patients at risk for poor outcomes, and the potential therapeutic implications, these results should be validated in larger prospective studies.

The Use of Liver Biopsy in Nonalcoholic Fatty Liver Disease: When to Biopsy and in Whom

Nonalcoholic fatty liver disease (NAFLD) is a common liver disorder that can be divided into benign steatosis or nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH). Elastography and scoring systems based on clinical features and routine biochemical testing can be used to assess fibrosis in patients with NAFLD. Patients with fibrosis are thought to have NASH. However, only a liver biopsy can reliably diagnose NAFLD and differentiate NAFL from NASH. Because medical therapy for NASH is not available, it is not necessary to perform a liver biopsy in all patients. Patients suspected of having NASH should undergo liver biopsy.

A simple scoring system using type IV collagen 7S and aspartate aminotransferase for diagnosing nonalcoholic steatohepatitis and related fibrosis

BACKGROUND

Recently we reported novel noninvasive scoring systems for diagnosing nonalcoholic steatohepatitis (NASH) and related fibrosis, namely FM-NASH index and FM-fibro index. They are highly accurate, however, they contain some items not widely used in clinical practice and require six or more items to diagnose both NASH and related fibrosis. By focusing on widely used items, we tried to identify convenient markers in common with the both diagnoses.

METHODS

To explore the markers for NASH and related fibrosis in nonalcoholic fatty liver disease (NAFLD) patients, we used data of 24 clinical items in our previous report. By logistic regression analysis, we identified items suitable for the both diagnoses. We then evaluated their accuracies by area under the receiver operator characteristic curves (AUROCs) on independent validation data.

RESULTS

We identified the combination of type IV collagen 7S and aspartate aminotransferase (AST) as the predictor both for NASH and related fibrosis. We developed a scoring system based on the combination and evaluated the prediction accuracy: the AUROCs for training/validation data sets are 0.857/0.769 for NASH and 0.918/0.842 for NASH-related fibrosis. The former was higher than that of NAFIC score, and the latter was higher than those of existing fibrosis markers: BARD score, FIB-4 index and NAFLD fibrosis score but lower than FM-fibro index.

CONCLUSIONS

The scoring system using type IV collagen 7S and AST named CA index can predict both NASH and related fibrosis in NAFLD patients with sufficient accuracy and could be a convenient diagnostic and screening tool for NASH and related fibrosis. The scoring system needs to be validated in independent larger populations from multiple clinical centers.

Current Modalities of Fibrosis Assessment in Non-alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a burgeoning global health concern. In the subset of NAFLD patients with non-alcoholic steatohepatitis (NASH), the presence of significant fibrosis at index assessment is associated with poor prognosis and increased mortality. Hence, there is a growing need to accurately assess and stage fibrosis. Liver biopsy, the current gold standard, has limitations with sampling error and is invasive, with associated inherent risk. This has led to a host of non-invasive means of assessing fibrosis, which has garnered relevance in a disease that requires serial assessment of fibrosis longitudinally over time. This review discusses, comprehensively, the various tools available to the clinician for the assessment of fibrosis, including the various scoring systems used in liver biopsy, the non-invasive means of serum biomarkers, such as the highly-validated NAFLD fibrosis score, and the imaging-based modalities, such as transient elastography and magnetic resonance elastography.

Fruit Fiber Consumption Specifically Improves Liver Health Status in Obese Subjects under Energy Restriction

The prevalence of non-alcoholic-fatty-liver-disease (NAFLD) is associated with obesity, diabetes, and metabolic syndrome (MS). This study aimed to evaluate the influence of two energy-restricted diets on non-invasive markers and scores of liver damage in obese individuals with features of MS after six months of follow-up and to assess the role of fiber content in metabolic outcomes. Seventy obese individuals from the RESMENA (Reduction of Metabolic Syndrome in Navarra) study were evaluated at baseline and after six months of energy-restricted nutritional intervention (American Heart Association (AHA) and RESMENA dietary groups). Dietary records, anthropometrical data, body composition by dual energy X-ray absorptiometry (DXA), and routine laboratory measurements were analyzed by standardized methods. Regarding liver status, cytokeratin-18 fragments and several non-invasive scores of fatty liver were also assessed. The RESMENA strategy was a good and complementary alternative to AHA for the treatment of obesity-related comorbidities. Participants with higher insoluble fiber consumption (≥7.5 g/day) showed improvements in fatty liver index (FLI), hepatic steatosis index (HIS), and NAFLD liver fat score (NAFLD_LFS), while gamma-glutamyl transferase (GGT) and transaminases evidenced significant improvements as a result of fruit fiber consumption (≥8.8 g/day). Remarkably, a regression model evidenced a relationship between liver status and fiber from fruits. These results support the design of dietary patterns based on the consumption of insoluble fiber and fiber from fruits in the context of energy restriction for the management of obese patients suffering fatty liver disease.

Development of Serum Marker Models to Increase Diagnostic Accuracy of Advanced Fibrosis in Nonalcoholic Fatty Liver Disease: The New LINKI Algorithm Compared with Established Algorithms

Background and Aim

Detection of advanced fibrosis (F3-F4) in nonalcoholic fatty liver disease (NAFLD) is important for ascertaining prognosis. Serum markers have been proposed as alternatives to biopsy. We attempted to develop a novel algorithm for detection of advanced fibrosis based on a more efficient combination of serological markers and to compare this with established algorithms.

Methods

We included 158 patients with biopsy-proven NAFLD. Of these, 38 had advanced fibrosis. The following fibrosis algorithms were calculated: NAFLD fibrosis score, BARD, NIKEI, NASH-CRN regression score, APRI, FIB-4, King´s score, GUCI, Lok index, Forns score, and ELF. Study population was randomly divided in a training and a validation group. A multiple logistic regression analysis using bootstrapping methods was applied to the training group. Among many variables analyzed age, fasting glucose, hyaluronic acid and AST were included, and a model (LINKI-1) for predicting advanced fibrosis was created. Moreover, these variables were combined with platelet count in a mathematical way exaggerating the opposing effects, and alternative models (LINKI-2) were also created. Models were compared using area under the receiver operator characteristic curves (AUROC).

Results

Of established algorithms FIB-4 and King´s score had the best diagnostic accuracy with AUROCs 0.84 and 0.83, respectively. Higher accuracy was achieved with the novel LINKI algorithms. AUROCs in the total cohort for LINKI-1 was 0.91 and for LINKI-2 models 0.89.

Conclusion

The LINKI algorithms for detection of advanced fibrosis in NAFLD showed better accuracy than established algorithms and should be validated in further studies including larger cohorts.

A Review of Western and Traditional Chinese Medical Approaches to Managing Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is a disease of attention because of increase in prevalence from 20% to 41%. The clinical and pathological conditions in patients with NAFLD range from steatosis alone to nonalcoholic steatohepatitis (NASH) with or without fibrosis to hepatic cancer. In the United States, NAFLD was the second-leading indication for liver transplant between 2004 and 2013. Although imaging studies such as magnetic resonance elastography and the use of diagnostic panels and scoring systems can provide a fairly accurate diagnosis of NAFLD, there are few treatment options for patients with mild to moderate disease other than lifestyle modification. Many of the currently used medical treatments have been shown to cause severe side effects and some have been shown to be associated with increased risk for certain types of cancer. In recent years, a number of traditional Chinese herbal treatments have been examined for their potential uses as treatment for NAFLD. In this review, we provide a general overview of NAFLD and a survey of Western pharmacologic drugs currently used to treat the disease as well as the results of recent studies on the effectiveness of traditional Chinese herbal remedies for managing nonalcoholic fatty liver disease.

Cost-effectiveness of non-invasive methods for assessment and monitoring of liver fibrosis and cirrhosis in patients with chronic liver disease: systematic review and economic evaluation

BACKGROUND

Liver biopsy is the reference standard for diagnosing the extent of fibrosis in chronic liver disease; however, it is invasive, with the potential for serious complications. Alternatives to biopsy include non-invasive liver tests (NILTs); however, the cost-effectiveness of these needs to be established.

OBJECTIVE

To assess the diagnostic accuracy and cost-effectiveness of NILTs in patients with chronic liver disease.

DATA SOURCES

We searched various databases from 1998 to April 2012, recent conference proceedings and reference lists.

METHODS

We included studies that assessed the diagnostic accuracy of NILTs using liver biopsy as the reference standard. Diagnostic studies were assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Meta-analysis was conducted using the bivariate random-effects model with correlation between sensitivity and specificity (whenever possible). Decision models were used to evaluate the cost-effectiveness of the NILTs. Expected costs were estimated using a NHS perspective and health outcomes were measured as quality-adjusted life-years (QALYs). Markov models were developed to estimate long-term costs and QALYs following testing, and antiviral treatment where indicated, for chronic hepatitis B (HBV) and chronic hepatitis C (HCV). NILTs were compared with each other, sequential testing strategies, biopsy and strategies including no testing. For alcoholic liver disease (ALD), we assessed the cost-effectiveness of NILTs in the context of potentially increasing abstinence from alcohol. Owing to a lack of data and treatments specifically for fibrosis in patients with non-alcoholic fatty liver disease (NAFLD), the analysis was limited to an incremental cost per correct diagnosis. An analysis of NILTs to identify patients with cirrhosis for increased monitoring was also conducted.

RESULTS

Given a cost-effectiveness threshold of £20,000 per QALY, treating everyone with HCV without prior testing was cost-effective with an incremental cost-effectiveness ratio (ICER) of £9204. This was robust in most sensitivity analyses but sensitive to the extent of treatment benefit for patients with mild fibrosis. For HBV [hepatitis B e antigen (HBeAg)-negative)] this strategy had an ICER of £28,137, which was cost-effective only if the upper bound of the standard UK cost-effectiveness threshold range (£30,000) is acceptable. For HBeAg-positive disease, two NILTs applied sequentially (hyaluronic acid and magnetic resonance elastography) were cost-effective at a £20,000 threshold (ICER: £19,612); however, the results were highly uncertain, with several test strategies having similar expected outcomes and costs. For patients with ALD, liver biopsy was the cost-effective strategy, with an ICER of £822.

LIMITATIONS

A substantial number of tests had only one study from which diagnostic accuracy was derived; therefore, there is a high risk of bias. Most NILTs did not have validated cut-offs for diagnosis of specific fibrosis stages. The findings of the ALD model were dependent on assuptions about abstinence rates assumptions and the modelling approach for NAFLD was hindered by the lack of evidence on clinically effective treatments.

CONCLUSIONS

Treating everyone without NILTs is cost-effective for patients with HCV, but only for HBeAg-negative if the higher cost-effectiveness threshold is appropriate. For HBeAg-positive, two NILTs applied sequentially were cost-effective but highly uncertain. Further evidence for treatment effectiveness is required for ALD and NAFLD.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42011001561.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Non-invasive methods for the diagnosis of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the commonest chronic liver disease and includes simple steatosis and nonalcoholic steatohepatitis (NASH). Since NASH progresses to cirrhosis more frequently and increases liver-related and cardiovascular disease risk substantially more than simple steatosis, there is a great need to differentiate the two entities. Liver biopsy is the gold standard for the diagnosis of NAFLD but its disadvantages, including the risk of complications and sampling bias, stress the need for developing alternative diagnostic methods. Accordingly, several non-invasive markers have been evaluated for the diagnosis of simple steatosis and NASH, including both serological indices and imaging methods. The present review summarizes the current knowledge on the role of these markers in the diagnosis of NAFLD. Current data suggest that ultrasound and the fibrosis-4 score are probably the most appealing methods for detecting steatosis and for distinguishing NASH from simple steatosis, respectively, because of their low cost and relatively high accuracy. However, currently available methods, both serologic and imaging, cannot obviate the need for liver biopsy for diagnosing NASH due to their substantial false positive and false negative rates. Therefore, the current role of these methods is probably limited in patients who are unwilling or have contraindications for undergoing biopsy.

Biomarkers of liver fibrosis

Liver fibrosis is the final common pathway for almost all causes of chronic liver injury. Liver fibrosis is now known to be a dynamic process having significant potential for resolution. Therefore, fibrosis prediction is an essential part of the assessment and management of patients with chronic liver disease. As such, there is strong demand for reliable liver biomarkers that provide insight into disease etiology, diagnosis, therapy, and prognosis in lieu of more invasive approaches such as liver biopsy. Current diagnostic strategies range from use of serum biomarkers to more advanced imaging techniques including transient elastography and magnetic resonance imaging. In addition to these modalities, there are other approaches including the use of novel, but yet to be validated, biomarkers. In this chapter, we discuss the biomarkers of liver fibrosis including the use of invasive and noninvasive biomarkers and disease-specific biomarkers in various chronic liver diseases.

The Wide and Complex Field of NAFLD Biomarker Research: Trends

Background. Nonalcoholic fatty liver disease is now acknowledged as a complex public health issue linked to sedentary lifestyle, obesity, and related disorders like type 2 diabetes and metabolic syndrome. Aims. We aimed to retrieve its trends out of the huge amount of published data. Therefore, we conducted an extensive literature search to identify possible biomarker and/or biomarker combinations by retrospectively assessing and evaluating common and novel biomarkers to predict progression and prognosis of obesity related liver diseases. Methodology. We analyzed finally 62 articles accounting for 157 cohorts and 45,288 subjects. Results. Despite the various approaches, most cohorts were considerably small and rarely comparable. Also, we found that the same standard parameters were measured rather than novel biomarkers. Diagnostics approaches appeared incomparable. Conclusions. Further collaborative investigations on harmonizing ways of data acquisition and identifying such biomarkers for clinical use are necessary to yield sufficient significant results of potential biomarkers.

Diet-induced mouse model of fatty liver disease and nonalcoholic steatohepatitis reflecting clinical disease progression and methods of assessment

Shortcomings of previously reported preclinical models of nonalcoholic steatohepatitis (NASH) include inadequate methods used to induce disease and assess liver pathology. We have developed a dietary model of NASH displaying features observed clinically and methods for objectively assessing disease progression. Mice fed a diet containing 40% fat (of which ∼18% was trans fat), 22% fructose, and 2% cholesterol developed three stages of nonalcoholic fatty liver disease (steatosis, steatohepatitis with fibrosis, and cirrhosis) as assessed by histological and biochemical methods. Using digital pathology to reconstruct the left lateral and right medial lobes of the liver, we made comparisons between and within lobes to determine the uniformity of collagen deposition, which in turn informed experimental sampling methods for histological, biochemical, and gene expression analyses. Gene expression analyses conducted with animals stratified by disease severity led to the identification of several genes for which expression highly correlated with the histological assessment of fibrosis. Importantly, we have established a biopsy method allowing assessment of disease progression. Mice subjected to liver biopsy recovered well from the procedure compared with sham-operated controls with no apparent effect on liver function. Tissue obtained by biopsy was sufficient for gene and protein expression analyses, providing the opportunity to establish an objective method of assessing liver pathology before subjecting animals to treatment. The improved assessment techniques and the observation that mice fed the high-fat diet exhibit many clinically relevant characteristics of NASH establish a preclinical model for identifying pharmacological interventions with greater likelihood of translating to the clinic.

The BARD score and the NAFLD fibrosis score in the assessment of advanced liver fibrosis in nonalcoholic fatty liver disease

Background

Non-alcoholic fatty liver disease (NAFLD) refers to a very wide clinical spectrum. Advanced fibrosis that accompanies disease leads to the development of cirrhosis and hepatocellular carcinoma. Thus, identification of patients with advanced fibrosis is essential. The aim of the present study was to compare the usefulness of NAFLD fibrosis and BARD scores in predicting fibrosis in NAFLD and to determine the risk factors of advanced fibrosis.

Material/Methods

The study included 126 patients with NAFLD. Fibrosis in liver biopsy was scored on a 5-point scale. The BARD and the NAFLD fibrosis scores were compared with the biopsy findings.

Results

Liver biopsy revealed 27 patients with advanced and 99 with mild/moderate fibrosis. Advanced fibrosis was statistically significantly more common in older patients with obesity, AST/ALT ratio ≥0.8, diabetes mellitus, and thrombocytes ≤200×10³/L. Positive predictive value, negative predictive value and AUROC curve for BARD score, and NAFLD fibrosis score were 68.57%, 96.70%, 0.865 and 70.59%, 98.11%, 0.919, respectively.

Conclusions

Both scores are capable of ruling out advanced fibrosis and markedly reducing the need for liver biopsies in patients with NAFLD. Obesity, diabetes mellitus, thrombocytes ≤200×10³/L, advanced age and AST/ALT ratio ≥0.8 are the risk factors of advanced fibrosis.

Suboptimal performance of simple noninvasive tests for advanced fibrosis in Chinese patients with nonalcoholic fatty liver disease

OBJECTIVE

To evaluate the diagnostic accuracy of some noninvasive fibrosis models in Chinese patients with nonalcoholic fatty liver disease (NAFLD).

METHODS

Consecutive biopsy-proven NAFLD patients were recruited from a single center from January 2005 to December 2010. Advanced fibrosis (stage 3 and 4) was defined using Kleiner criteria. The area under the receiver operating characteristic curve (AUROC) was used to compare the diagnostic accuracy of the NAFLD fibrosis score (NFS), FIB-4 index, aspartate transaminase (AST)/platelet ratio index (APRI), AST/alanine transaminase (ALT) ratio (AAR) and body mass index (BMI)-AAR-Diabetes (BARD) score.

RESULTS

Of the patients with NAFLD, 79.6% were males with a mean age of 37.1 years, mean BMI of 26.1 kg/m(2) and 41.4% of them had nonalcoholic steatohepatitis, and 24 (15.8%) had advanced fibrosis. The AUROC of the FIB-4 index, APRI, AAR, NFS and BARD score for advanced fibrosis were 0.756, 0.742, 0.670, 0.653 and 0.642 (P < 0.05 for all), respectively. A concordant negative predictive value of approximately 90% was indicated whereas the positive predictive values were modest for all tests, and only the FIB-4 index yielded a higher positive likelihood ratio of 7.65. Using these cut-off values of tests for excluding advanced fibrosis could reduce the use of liver biopsy in 56.6-74.3% of the patients, with a minor false negative rate of 5.3-9.9%.

CONCLUSIONS

Although slightly less accurate than liver biopsy, simple noninvasive tests can reliably exclude advanced fibrosis in Chinese NAFLD patients in our center. FIB-4 index performs better than the other tests under examination.

Can NASH be diagnosed, graded, and staged noninvasively?

Nonalcoholic bland steatosis and nonalcoholic steatohepatitis (NASH) are stages in the spectrum of nonalcoholic fatty liver disease (NAFLD). NASH may progress to end-stage liver disease. Liver biopsy distinguishes between patients with NASH and no NASH and can stage fibrosis. Markers of hepatocyte apoptosis hold promise as noninvasive tests for NASH diagnosis. Several scoring systems that combine routine clinical and laboratory variables and some proprietary panels can assist in predicting fibrosis severity. Noninvasive imaging modalities are reasonably accurate available tools to determine severity of fibrosis in NAFLD, but none of them yet can replace liver biopsy.

Features, diagnosis, and treatment of nonalcoholic fatty liver disease

As the global incidence of obesity has increased, nonalcoholic fatty liver disease (NAFLD) has become a worldwide health concern. NAFLD occurs in children and adults of all ethnicities and includes isolated fatty liver and nonalcoholic steatohepatitis (NASH). Patients with NASH are at risk for developing cirrhosis, hepatic decompensation, and hepatocellular carcinoma and have increased all-cause mortality. NAFLD is associated with a variety of clinical conditions and is an independent risk factor for hepatocellular carcinoma. The pathogenesis of NAFLD and the specific steps that lead to NASH and advanced fibrosis are not fully understood, although researchers have found that a combination of environmental, genetic, and metabolic factors lead to advanced disease. There have been improvements in noninvasive radiographic methods to diagnose NAFLD, especially for advanced disease. However, liver biopsy is still the standard method of diagnosis for NASH. There are many challenges to treating patients with NASH, and no therapies have been approved by the U.S. Food and Drug Administration; multimodal approaches are being developed and becoming the standard of care. We review pathogenesis and treatment approaches for the West's largest liver-related public health concern.

Non-invasive Diagnosis of Fibrosis in Non-alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in developed as well as in developing countries. Its prevalence continues to rise currently affecting approximately 20-30% of adults and 10% of children in the United States. Non-alcoholic fatty liver disease represents a wide spectrum of conditions ranging from fatty liver, which in general follows a benign non-progressive clinical course, to non-alcoholic steatohepatitis (NASH), a more serious form of NAFLD that may progress to cirrhosis and end-stage liver disease. Liver biopsy remains the gold standard for evaluating the degree of hepatic necroinflammation and fibrosis; however, several non-invasive investigations, such as serum biomarkers, have been developed to establish the diagnosis and also to evaluate treatment response. There has been a substantial development of non-invasive risk scores, biomarker panels, and radiological modalities to identify at risk patients with NAFLD without recourse to liver biopsy on a routine basis. Examples include combination of serum markers like NAFLD fibrosis score (NFS), BARD score, fibrometer, FIB4, and non-invasive tools like fibroscan which assess fibrosis in patients with NAFLD. Other markers of fibrosis that have been evaluated include high-sensitivity C-reactive protein, plasma pentraxin 3, interleukin-6, and cytokeratin-18. This review focuses on the methods currently available in daily clinical practice in hepatology and touches briefly on the potential future markers under investigation.

Meta-analysis: natural history of non-alcoholic fatty liver disease (NAFLD) and diagnostic accuracy of non-invasive tests for liver disease severity

BACKGROUND. NAFLD ranges from simple steatosis (SS) to non-alcoholic steatohepatitis (NASH). The natural history of NAFLD and the optimal strategy to identify subjects with progressive liver disease are unclear. Objectives. To assess the evidence in: (1) natural history of NAFLD; and (2) non-invasive methods to differentiate NAFLD histological subtypes. DESIGN AND SETTING. Among 4185 articles published on MEDLINE, Cochrane Library, EMBASE, Pubmed, national and International meeting abstracts through July 2010, 40 articles assessing the natural history of NAFLD and 32 articles evaluating the diagnostic accuracy of non-invasive tests against liver biopsy (LB) were included. MEASUREMENTS. Two reviewers retrieved articles and evaluated study quality by appropriate scores. Main outcomes were pooled using random- or fixed-effects models. RESULTS. NAFLD has an increased overall mortality (OR: 1.57, 95% CI: 1.18-2.10), deriving from liver-related and cardiovascular disease, and a 2-fold risk of diabetes. Compared to SS, NASH has a higher liver-related (OR for NASH: 5.71, 2.31-14.13; OR for NASH with advanced fibrosis: 10.06, 4.35-23.25), but not cardiovascular mortality (OR: 0.91, 0.42-1.98). Three non-invasive methods received independent validation: pooled AUROC, sensitivity and specificity of cytokeratin-18 for NASH are 0.82 (0.78-0.88), 0.78 (0.64-0.92), 0.87 (0.77-0.98). For NASH with advanced fibrosis, pooled AUROC, sensitivity and specificity of NAFLD fibrosis score and Fibroscan are 0.85 (0.80-0.93), 0.90 (0.82-0.99), 0.97 (0.94-0.99) and 0.94 (0.90-0.99), 0.94 (0.88-0.99) and 0.95 (0.89-0.99). CONCLUSIONS. NAFLD warrants screening for cardio-metabolic risk and for progressive liver disease. The combination of three noninvasive tests with LB may optimally individuate patients with NASH, with or without advanced fibrosis.

Systematic review: the diagnosis and staging of non-alcoholic fatty liver disease and non-alcoholic steatohepatitis

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) has become the most prevalent cause of liver disease in Western countries. The development of non-alcoholic steatohepatitis (NASH) and fibrosis identifies an at-risk group with increased risk of cardiovascular and liver-related deaths. The identification and management of this at-risk group remains a clinical challenge.

AIM

To perform a systematic review of the established and emerging strategies for the diagnosis and staging of NAFLD.

METHODS

Relevant research and review articles were identified by searching PubMed, MEDLINE and EMBASE.

RESULTS

There has been a substantial development of non-invasive risk scores, biomarker panels and radiological modalities to identify at-risk patients with NAFLD without recourse to liver biopsy on a routine basis. These modalities and algorithms have improved significantly in their diagnosis and staging of fibrosis and NASH in patients with NAFLD, and will likely impact on the number of patients undergoing liver biopsy.

CONCLUSIONS

Staging for NAFLD can now be performed by a combination of radiological and laboratory techniques, greatly reducing the requirement for invasive liver biopsy.