Characterization of nonalcoholic fatty liver disease unrelated to the metabolic syndrome

Severe, but not mild to moderate, non-alcoholic fatty liver disease associated with increased risk of subclinical coronary atherosclerosis

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is associated with high risk of cardiovascular disease. The prevalence is increasing to 45-65% in the general population with routine health check-up, and most subjects have the mild degree NAFLD in recent years. Moreover, there are no studies on the association between NAFLD severity and coronary atherosclerosis in the real-world setting by ultrasonography.

METHODS

The aim of this study was to determine the relationship between the severity of NAFLD and subclinical coronary atherosclerosis. Overall, 817 subjects meet criteria for NAFLD were enrolled in the retrospective cohort study (155 subjects were excluded). The severity of NAFLD was divided into the normal, mild, moderate and severe degree based on the finding of abdominal ultrasonography. The assessment of coronary atherosclerosis was based on CAC scan/coronary CT angiography finding in terms of CAC score ≧ 100, CAC score ≧ 400, CAD-RADS ≧ 3 and presence of vulnerable plaque(s).

RESULTS

A significant linear trend was observed between the severity of NAFLD and subclinical coronary atherosclerosis. Compared with the reference group (including normal, mild, and moderate NAFLD), severe degree NAFLD was the independently associated risk of subclinical coronary atherosclerosis in term of CAC score ≧ 100, CAC score ≧ 400, CAD-RADS ≧ 3 and presence of vulnerable plaque(s) based on binary logistic regression after adjustment for FRS score and body fat percentage.

CONCLUSIONS

Severe degree, but not mild to moderate, was associated with high risk of subclinical coronary atherosclerosis, independently of FRS score and body-fat percentage.

Non-alcoholic fatty liver disease: A growing public health problem in Turkey

Non-alcoholic fatty liver disease (NAFLD) is histologically classified as either non-alcoholic fatty liver or non-alcoholic steatohepatitis (NASH). NASH is the progressive subtype of NAFLD. Individuals with NASH are at significant risk of developing hepatic fibrosis, cirrhosis, hepatocellular carcinoma, and liver-related and all-cause mortality. NAFLD is closely associated with obesity, type 2 diabetes mellitus (T2DM), metabolic syndrome, and cardiovascular events. Its prevalence is estimated to be above 30% in Turkey; and recent studies confirm this estimate. According to these studies, the prevalence of NAFLD in Turkey is between 48.3% and 60.1%. Currently, Turkey can be considered a risky region in terms of NAFLD burden as it is the most obese country in Europe with an obesity prevalence of 32.1% according to the 2016 World Health Organization data. Moreover, along with the increasing prevalence of obesity and T2DM in Turkey, the burden of NAFLD is estimated to increase in the upcoming decade. Despite the growing burden, we lack well-designed systemic studies that investigate NAFLD and its marked histological severity. In this review, we present studies on the burden of NAFLD and NASH, the natural history of NAFLD, and its association with other systemic diseases conducted with Turkish populations.

Growing burden of nonalcoholic fatty liver disease in Turkey: A single-center experience

BACKGROUND/AIMS

Nonalcoholic fatty liver disease (NAFLD), which consists of nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH), is a growing epidemic in Turkey, considering the recent alarming prevalence of 48.3%. Patients with NASH and/or liver fibrosis are more likely to progress to advanced liver disease. In this single-center study, we sought to describe the clinical and histological characteristics of a sample of Turkish patients with biopsy-proven NAFLD, who were enrolled over a 4-year period.

MATERIALS AND METHODS

This is a retrospective analysis of prospectively collected data from a total of 468 patients (224 males, 244 females; median age, 47 [18-71]. The study cohort consisted of patients with biopsy-proven NAFLD who were followed up at our outpatient clinic from 2009 to 2010 and from 2017 to 2018. Histological classification of the biopsies was performed according to the Steatosis, Activity and Fibrosis (SAF) scoring allowing the use of Fatty Liver Inhibition of Progression (FLIP) algorithm and the NAFLD Activity Score (NAS) scoring system.

RESULTS

Based on the SAF scoring, most patients (90.4%) had biopsy-proven NASH, whereas the NAFL was much rarer (9.6%). The prevalence of significant fibrosis (≥F2), advanced fibrosis (≥F3), and cirrhosis (F=4) was 35.0%, 17.5%, and 3.8%, respectively. The percentage of lean, overweight, and obese patients with NAFLD was 6.4%, 32.6%, and 61%, respectively. Metabolic syndrome was prevalent in 63% of the patients and Type 2 diabetes mellitus in 33.5%.

CONCLUSION

The growing burden of NAFLD as a public health problem in Turkey is underscored by its marked histological severity in terms of NASH and fibrosis. Well-conducted clinical trials will be essential for slowing down the NASH progression.

Prevalence and Risk Factors of Metabolic Associated Fatty Liver Disease in Xinxiang, China

Metabolic associated fatty liver disease (MAFLD) is recognized as the liver disease component of metabolic syndrome, which is mainly related to insulin resistance and genetic susceptibility. It is the most prevalent chronic liver disease worldwide. With rapid lifestyle transitions, its prevalence worldwide is increasing, and tremendous challenges in controlling this pandemic are arising. The objective of this study was to investigate the prevalence and risk factors of MAFLD in rural areas of Xinxiang, Henan in 2017. We conducted a cross-sectional analysis of rural inhabitants aged 20–79 years in Xinxiang, Henan in 2017, using cluster random sampling (N = 9140). Physical examinations were conducted at local clinics from April to June 2017. After overnight fasting, all participants underwent physical examinations, blood routine tests, biochemical examinations, and liver ultrasound and completed questionnaires. We investigated the crude and age-adjusted MAFLD prevalence and analyzed the characteristics of those with, and without, MAFLD, using logistic regression. Approximately 2868 (31.38%) participants were diagnosed with MAFLD. The overall age-adjusted MAFLD prevalence was 29.85% (men: 35.36%; women: 26.49%). The MAFLD prevalence increased with age, and peaked at the 50–59-year age group, and then began to decline. Higher body mass index, waist circumference, percentage of lymphocytes, levels of hemoglobin, platelet count, triglyceride, fasting plasma glucose, and serum uric acid were independently and positively correlated with MAFLD; In contrary, active physical activity and high-density lipoprotein cholesterol were negatively correlated with MAFLD. In summary, the MAFLD prevalence in the study population was 29.85%. Higher body mass index, waist circumference, percentage of lymphocytes, levels of hemoglobin, platelet count, triglyceride, fasting plasma glucose, and serum uric acid were risk factors for MAFLD.

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

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

Exploration of serum sensitive biomarkers of fatty liver in dairy cows

Serum proteins are sensitive with diseases in dairy cows, and some of them could be used as biomarkers for fatty liver. This study aimed to explore serum biomarkers for fatty liver in dairy cows. A total of 28 early lactating dairy cows were chosen from a commercial dairy herds, liver samples were collected for determining concentration of triacylglycerol (TAG), and serum samples were collected for measuring fibroblast growth factor-21 (FGF-21), adiponectin, Lipoprotein-associated phospholipase A2 (LP-PLA2), and hemoglobin (Hb). Dairy cows were divided into fatty liver (liver TAG > 5%, wet weight) and control group (liver TAG < 5%, wet weight). Concentration of FGF-21 was greater in fatty liver cows, while the concentration of LP-PLA2 and Hb was less. The concentration of FGF-21 and total Hb had strong correlation with the liver TAG as well as good prediction power (kappa value = 0.79 and 0.58, respectively). These results suggested that the serum concentration of FGF-21 and total Hb could be potentially used as fatty liver biomarkers in lactating dairy cows.

Effect of Endoplasmic Reticular Stress on Free Hemoglobin Metabolism and Liver Injury

Elevated soluble (s) CD163 and free hemoglobin (Hb) levels predict fatty liver progression; however, the molecular mechanisms underlying Hb metabolism and liver injury remain undefined. We investigated the effects of endoplasmic reticular (ER) stress on red blood cell (RBC) rheology and free Hb recycling pathways. ER stress was induced in Sprague-Dawley rats by an intraperitoneal injection of tunicamycin (TM) (50, 100, and 200 μg/100 g body weight (BW)) or an intravenous injection of Hb (5 mg/100 g BW). A TM injection increased sCD163 levels, attenuated free Hb uptake, and maintained RBC aggregability. An Hb injection increased serum LVV-hemorphin-7 and total bilirubin levels, but this effect was suppressed by TM. A Western blot analysis showed that ER stress suppressed Hb degradation in the liver through downregulation of globin degradation proteins cathepsin D and glyoxalase-1, as well as heme degradation protein heme oxyganase-1 and keap-1 expression. An ER stress activator also increased the translocation of nuclear factor (NF)-κB (p65) and nuclear factor-erythroid 2-related factor 2 (Nrf2) to nuclei. In conclusion, ER stress triggers ineffective Hb metabolism via altering globin and heme iron degradation pathways. Inability to recycle and metabolize free Hb may underlie the association between iron dysfunction and liver injury.

Non-alcoholic Fatty Liver Disease in Lean Subjects: Characteristics and Implications

Non-alcoholic fatty liver disease (NAFLD) is commonly diagnosed in obese subjects; however, it is not rare among lean individuals. Given the absence of traditional risk factors, it tends to remain under-recognised. The metabolic profiles of lean NAFLD patients are frequently comparable to those of obese NAFLD patients. Though results from several studies have been mixed, it has been generally revealed that lean subjects with NAFLD have minor insulin resistance compared to that in obese NAFLD. Several genetic variants are associated with NAFLD without insulin resistance. Some data suggest that the prevalence of steatohepatitis and advanced fibrosis do not differ significantly between lean and obese NAFLD; however, the former tend to have less severe disease at presentation. The underlying pathophysiology of lean NAFLD may be quite different. Genetic predispositions, fructose- and cholesterol-rich diet, visceral adiposity and dyslipidaemia have potential roles in the pathogenic underpinnings. Lean NAFLD may pose a risk for metabolic disturbances, cardiovascular morbidity or overall mortality. Secondary causes of hepatic steatosis are also needed to be ruled out in lean subjects with NAFLD. The effectiveness of various treatment modalities, such as exercise and pharmacotherapy, on lean NAFLD is not known. Weight loss is expected to help lean NAFLD patients who have visceral obesity. Further investigation is needed for many aspects of lean NAFLD, including mechanistic pathogenesis, risk assessment, natural history and therapeutic approach.

Prevalence and determinants of non-alcoholic fatty liver disease in lifelines: A large Dutch population cohort

Background & aims

Non-alcoholic fatty liver disease is an increasing health issue that develops rather unnoticed with obesity, type 2 diabetes mellitus and metabolic syndrome. We investigated prevalence, determinants and associated metabolic abnormalities of non-alcoholic fatty liver disease in the largest population-based cohort to date.

Methods

Biochemical characteristics, type 2 diabetes mellitus and metabolic syndrome were determined in the Lifelines Cohort Study (N = 167,729), a population-based cohort in the North of the Netherlands. Non-alcoholic fatty liver disease was defined as Fatty Liver Index (FLI)≥60. Exclusion criteria were age <18 years, immigrants, missing data to assess FLI and metabolic syndrome, excessive alcohol use, previous-diagnosed hepatitis or cirrhosis and non-fasting blood sampling.

Results

Out of 37,496 included participants (median age 44 years, 62.1% female), 8,259 (22.0%) had a FLI≥60. Individuals with a FLI≥60 were more often male, older, obese, had higher levels of hemoglobinA1c, fasting glucose, liver enzymes, total cholesterol, low-density lipoprotein cholesterol, triglycerides, c-reactive protein and leucocytes and lower high-density lipoprotein cholesterol (all P<0.0001). Participants with a FLI≥60 showed higher prevalence of type 2 diabetes mellitus (9.3% vs. 1.4%), metabolic syndrome (54.2% vs. 6.2%), impaired renal function (20.1% vs. 8.7%) and cardiovascular disease (4.6% vs. 1.6%) (all P<0.0001). Multivariable logistic analysis showed that smoking, hemoglobin, leucocytes, c-reactive protein, platelets, alanine aminotransferase, alkaline phosphatase, albumin, impaired renal function (OR 1.27, 95%CI 1.15–1.41), metabolic syndrome (OR 11.89, 95%CI 11.03–12.82) and its individual components hyperglycemia (OR 2.53, 95%CI 2.34–2.72), hypertension (OR 1.89, 95%CI 1.77–2.01) and reduced high-density lipoprotein cholesterol (OR 3.44, 95%CI 3.22–3.68) were independently associated with suspected non-alcoholic fatty liver disease (all P<0.0001).

Conclusion

Twenty-two percent (22.0%) of the population in the North of the Netherlands is suspected to suffer from non-alcoholic fatty liver disease, coinciding with a significant increased risk of type 2 diabetes mellitus, metabolic syndrome, cardiovascular disease and impaired renal function.

Associations between hemoglobin concentrations and the development of incidental metabolic syndrome or nonalcoholic fatty liver disease

AIMS

Hemoglobin (Hb) is known to be associated with both nonalcoholic fatty liver disease (NAFLD) and metabolic syndrome (MS). We evaluated the relationship between serum Hb levels and the development of MS or NAFLD.

METHODS

A retrospective cohort study was conducted. We recruited participants who underwent abdominal ultrasonography and blood samplings in both 2005 and 2010.

RESULTS

Graded independent relationships were observed between higher Hb levels and the incidence of MS and NAFLD. After adjusting for age, body mass index, and fasting glucose, high-density lipoprotein cholesterol and triglyceride levels, the risk of developing MS was significantly higher according to the Hb quartiles in men (P for trend=0.027). The adjusted odds ratio (OR) and 95% confidence intervals (CIs) for the highest Hb quartile was 1.81 (1.06-3.10) for women and 1.43 (1.00-2.05) for men. The risk of developing NAFLD was also significantly higher according to the Hb quartiles in men (P for trend=0.03). The adjusted OR and 95% CI for the highest Hb quartile was 1.18 (0.73-1.91) in women and 1.76 (1.16-2.66) in men.

CONCLUSIONS

The risk of developing either MS or NAFLD was significantly associated with serum Hb levels in men. These findings have implications in the clinical availability of serum Hb as a predictor of MS and NAFLD.

Mitochondrial Molecular Pathophysiology of Nonalcoholic Fatty Liver Disease: A Proteomics Approach

Nonalcoholic fatty liver disease (NAFLD) is a chronic liver condition that can progress to nonalcoholic steatohepatitis, cirrhosis and cancer. It is considered an emerging health problem due to malnourishment or a high-fat diet (HFD) intake, which is observed worldwide. It is well known that the hepatocytes’ apoptosis phenomenon is one of the most important features of NAFLD. Thus, this review focuses on revealing, through a proteomics approach, the complex network of protein interactions that promote fibrosis, liver cell stress, and apoptosis. According to different types of in vitro and murine models, it has been found that oxidative/nitrative protein stress leads to mitochondrial dysfunction, which plays a major role in stimulating NAFLD damage. Human studies have revealed the importance of novel biomarkers, such as retinol-binding protein 4, lumican, transgelin 2 and hemoglobin, which have a significant role in the disease. The post-genome era has brought proteomics technology, which allows the determination of molecular pathogenesis in NAFLD. This has led to the search for biomarkers which improve early diagnosis and optimal treatment and which may effectively prevent fatal consequences such as cirrhosis or cancer.

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

BACKGROUND

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSION

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

Nonalcoholic fatty liver disease-related cardiovascular risk: Is there an association with blood hemoglobin levels?

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in Western countries. There is emerging evidence on the relationship between NAFLD and increased cardiovascular risk. NAFLD is strongly associated with metabolic syndrome, but several other entities play a role in the pathogenesis of NAFLD more than metabolic syndrome. Currently, studies suggest that elevated hemoglobin levels are associated not only with the existence of nonalcoholic steatohepatitis but also with the severity of hepatic fibrosis. In this review, we aimed to discuss the potential role of high hemoglobin levels in the pathogenesis of NAFLD and NAFLD-associated cardiovascular risk.

Hb and dyslipidaemia as predicting markers of serum alanine aminotransferase elevation in Chinese adolescents

OBJECTIVE

Fe is an essential element for erythropoiesis and Hb synthesis. High Hb levels affect the blood's viscosity and are associated with cardiovascular dysfunction. The aim of the present study was to examine relationships of Hb and cardiometabolic abnormalities with the risk of alanine aminotransferase (ALT) elevation in adolescents.

DESIGN

A population-based, cross-sectional study.

SETTING

National Nutrition and Health Survey in Taiwan (2010-2011, adolescents).

SUBJECTS

Healthy adolescents aged 13-18 years.

RESULTS

In total, 1941 adolescents (963 boys and 978 girls) were entered in the study. The mean age was 15·3 (sd 0·1) years (boys, 15·3 (sd 0·1) years; girls, 15·2 (sd 0·1) years). ALT tertile cut-off points for boys were 11 and 16 U/l, and for girls were 9 and 12 U/l. Girls without dyslipidaemia and presenting in the highest quartile (Q1) of Hb (>13·6 g/dl) were 1·89 and 3·76 times more likely to have raised serum ALT (9 and >12 U/l, respectively) than the reference (lowest quartile of Hb (Q1), 12 U/l) than the reference (Q1 of Hb, 15·4 g/dl), who were 7·40 times more likely to have elevated serum ALT of >16 U/l than the reference (Q1 of Hb, <14·1 g/dl).

CONCLUSIONS

Our findings suggest that an increased Hb level is a predictor of elevated serum ALT in adolescent girls with dyslipidaemia. Our study also highlights the importance of further research to establish cut-off points for Hb and its utility in diagnosing and preventing the onset of dyslipidaemia in adolescents.

Non-Alcoholic Steatohepatitis-Related Hepatocellular Carcinoma: A Growing Epidemic?

Within developed countries the incidence of hepatocellular carcinoma (HCC) has been progressively increasing despite diagnosing fewer new cases of cirrhosis linked to viral hepatitis and alcohol consumption. This increased incidence parallels the epidemic of morbid obesity and metabolic syndrome and may be secondary to non-alcoholic steatohepatitis (NASH)-related HCC. The aims of this chapter are to (1) define the natural history of non-alcoholic fatty liver disease/NASH, (2) discuss the relationship between cryptogenic cirrhosis and NASH-related cirrhosis, (3) compare the presentation and treatment of NASH-related HCC to viral hepatitis-related cirrhosis and (4) identify the genetic factors associated with NASH and NASH-related HCC.

Measurements of serum procollagen-III peptide and M30 do not improve the diagnostic accuracy of transient elastography for the detection of hepatic fibrosis in patients with nonalcoholic fatty liver disease

BACKGROUND

Transient elastography (TE) has recently emerged as an accurate noninvasive imaging method for the diagnosis of liver fibrosis in nonalcoholic fatty liver disease (NAFLD). Here, we tested whether adding serum measures of serum procollagen-III peptide (PIIIP) and caspase-cleaved cytokeratin 18 fragment (M30) to TE could improve its diagnostic accuracy in patients with biopsy-proven NAFLD.

PATIENTS AND METHODS

TE was performed in 87 patients with NAFLD. Serum PIIIP and M30 levels were determined by enzyme-linked immunosorbent assay. Liver histology was considered the gold standard. The diagnostic accuracies were assessed by measuring the area under the receiver operating curve.

RESULTS

At histopathological examination, 34 patients (39.1%) had significant fibrosis (F2-F4) and 19 patients (21.8%) had advanced fibrosis (F3-F4). Both TE and serum M30 levels were independent predictors of fibrosis, whereas no association was found with PIIIP. No significant differences in terms of sensitivity and specificity for both significant and advanced fibrosis were evident for TE, serum M30, or their combination. Moreover, the area under the receiver operating curves of serum M30 combined with TE did not differ significantly from those of either test alone.

CONCLUSION

Both TE and serum M30 levels are accurate for the noninvasive diagnosis of fibrosis in NAFLD. However, their combination did not improve the overall diagnostic accuracy.

Characterization of lean patients with nonalcoholic fatty liver disease: potential role of high hemoglobin levels

OBJECTIVE

Overweight and obesity are major risk factors for the development of nonalcoholic fatty liver disease (NAFLD). However, a minority of NAFLD patients have a body mass index (BMI) <25 kg/m(2) (lean NAFLD). We sought to investigate whether significant differences exist between lean NAFLD and more common forms of NAFLD associated with overweight/obesity.

PATIENTS AND METHODS

A total of 483 consecutive patients with biopsy-proven NAFLD were enrolled. Lean NAFLD was defined as having a BMI <25 kg/m(2). We identified 37 patients with lean NAFLD (7.6%).

RESULTS

Compared with NAFLD patients with overweight/obesity, lean NAFLD patients were younger, had lower blood pressure values, higher levels of hemoglobin, a lower prevalence of the metabolic syndrome, and less severe hepatic fibrosis. In NAFLD patients with overweight/obesity, diabetes was the only independent predictor of nonalcoholic steatohepatitis (NASH). In lean NAFLD, the only variable independently associated with NASH was hemoglobin. Alanine aminotransferase and diabetes were independent predictors of fibrosis ≥2 in NAFLD patients with overweight/obesity, whereas hemoglobin was the only independent predictor of fibrosis ≥2 in lean NAFLD.

CONCLUSION

In summary, lean NAFLD patients are younger and show less severe hepatic fibrosis. However, such subjects have higher hemoglobin levels, which seem to predict the histological severity.

Nonalcoholic fatty liver disease as a potential risk factor of cardiovascular disease

Nonalcoholic fatty liver disease (NAFLD) is the hepatic component of the metabolic syndrome. The aim of this review is to summarize the available data linking NAFLD with cardiovascular disease (CVD). The following topics are reviewed: (a) the clinical evidence linking NAFLD to increased prevalence of CVD; (b) the relationship between NAFLD (which is diagnosed by liver biopsy, serum liver enzymes, or ultrasonography) and incidence of CVD; (c) the mechanism linking NAFLD to CVD and clinical implication; and (d) the potential impact of NAFLD treatment on cardiac complications. CVD dictates the outcome (or outcomes) in patients with NAFLD more frequently and to a greater extent than does the progression of liver disease. NAFLD patients have a higher risk of all-cause death than the general population, mainly because of CVD or liver-related causes. The biologic mechanism linking NAFLD and CVD might be associated with various factors, involving a complex interaction among insulin resistance, oxidative stress, abnormal adipocytokine profile, endothelial dysfunction, lipid abnormalities, and activation of inflammatory cascade. Lifestyle modifications and pharmacotherapy are helpful to treat patients with NAFLD. NAFLD is likely to be associated with an increased risk of CVD, and raises the possibility that NAFLD may not only be a marker but also an early mediator of CVD.

Comparison of noninvasive scores for the detection of advanced fibrosis in patients with nonalcoholic fatty liver disease

BACKGROUND

The presence of advanced liver fibrosis portends a poor prognosis in nonalcoholic fatty liver disease (NAFLD). We aimed to compare the diagnostic performance of five noninvasive scores [aspartate aminotransferase/platelet ratio (APRI), BARD, FIB-4, NAFLD fibrosis score (NFSA), and FibroMeter] for the assessment of advanced stages of fibrosis (F ≥ 3) in patients with biopsy-proven NAFLD.

METHODS

APRI, BARD, FIB-4, NFSA, and FibroMeter scores were determined in 142 patients with NAFLD. The histopathological analysis of liver biopsies was considered the gold standard. Sensitivity and specificity were calculated for each noninvasive test using receiver operating characteristic (ROC) curve analysis, with a cut-off value of F ≥ 3 for advanced fibrosis. The diagnostic accuracies were assessed by measuring the area under the ROC curve (AUROC). The AUROCs for different noninvasive tests were compared using paired significance tests.

RESULTS

At histopathological examination, 40 patients (28.2%) had a fibrosis stage F0, 50 patients (35.2%) had F1, 22 patients (15.5%) had F2, 20 patients (14.1%) had F3, and 10 patients (7.0%) had F4. The sensitivity of APRI, BARD, FIB-4, NFSA, and FibroMeter scores for advanced fibrosis was 70.0, 73.3, 70.0, 66.7, and 66.7%, respectively, and the specificity was 74.5, 66.4, 71.8, 71.8, and 74.5%, respectively. No significant differences in terms of sensitivity and specificity were evident for the five noninvasive scores. Moreover, the AUROCs did not differ significantly for all scores.

CONCLUSION

Our study suggests that different noninvasive scores have similar accuracy for the diagnosis of advanced hepatic fibrosis in NAFLD.

Gallstone disease does not predict liver histology in nonalcoholic fatty liver disease

Background/Aims

We sought to examine whether the presence of gallstone disease (GD) in patients with biopsy-proven nonalcoholic fatty liver disease (NAFLD) is associated with liver fibrosis and histological nonalcoholic steatohepatitis (NASH) score.

Methods

We included 441 Turkish patients with biopsy-proven NAFLD. GD was diagnosed in the presence of sonographic evidence of gallstones, echogenic material within the gallbladder with constant shadowing and little or no visualization of the gallbladder or absence of gallbladder at ultrasonography, coupled with a history of cholecystectomy.

Results

Fifty-four patients (12.2%) had GD (GD+ subjects). Compared with the GD- subjects, GD+ patients were older, had a higher body mass index and were more likely to be female and have metabolic syndrome. However, GD+ patients did not have a higher risk of advanced fibrosis or definite NASH on histology. After adjustment for potential confounding variables, the prevalence of GD in NAFLD patients was not associated with significant fibrosis (≥2) (odds ratio [OR], 1.06; 95% confidence interval [CI], 0.53 to 2.21; p=0.68) or definite NASH (OR, 1.03; 95% CI, 0.495 to 2.12; p=0.84).

Conclusions

The presence of GD is not independently associated with advanced fibrosis and definite NASH in adult Turkish patients with biopsy-proven NAFLD.

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

BACKGROUND

Noninvasive markers that purport to distinguish patients with non-alcoholic fatty liver disease (NAFLD) with fibrosis from those without must be evaluated rigorously for their classification accuracy. Herein, we seek to compare the diagnostic performances of three different noninvasive methods (FibroMeter™ NAFLD score, NAFLD Fibrosis score (NFSA), and Transient Elastrography [TE]) for the detection of liver fibrosis in NAFLD patients.

METHODS

A total of 88 patients with biopsy-proven NAFLD were included. The Kleiner system was used for grading fibrosis in liver biopsies. The FibroMeter™ NAFLD score was determined using a proprietary algorithm (regression score). The NFSA score was calculated based on age, hyperglycemia, body mass index, platelets, albumin and serum aminotransferase levels. TE was performed using the Fibroscan apparatus.

RESULTS

The sensitivities/specificities for the FibroMeter™ NAFLD score, NFSA, and TE for the diagnosis of significant fibrosis (F2 + F3 + F4 fibrosis) were 38.6%/86.4%, 52.3%/88.6%, and 75.0%/93.2%, respectively. The areas under the receiver operating characteristic curves of TE were significantly higher than those of both the FibroMeter™ NAFLD score and NFSA. No significant differences were found between the FibroMeter™ NAFLD score and NFSA for the detection of significant and severe fibrosis, although the diagnostic performance of the FibroMeter™ NAFLD score was higher than that of the NFSA score for cirrhosis.

CONCLUSIONS

In summary, TE showed the best diagnostic performance for the noninvasive assessment of liver fibrosis in NAFLD patients. The diagnostic performances of the FibroMeter™ NAFLD score and NFSA did not differ significantly for the detection of both significant and severe fibrosis.

Non-alcoholic fatty liver disease: What has changed in the treatment since the beginning?

Non-alcoholic fatty liver disease (NAFLD) is an umbrella term to describe the entire spectrum of this common liver disease. In patients with NAFLD, especially those with non-alcoholic steatohepatitis (NASH), most often have one or more components of the metabolic syndrome, but this is not universal. Although most patients with NAFLD share many clinical features, only a subset of patients develops significant liver inflammation and progressive fibrosis. On the other hand, not all patients with NASH exhibit insulin resistance. NASH can be seen in patients who are lean and have no identifiable risk factors. Many clinical studies have tried numerous drugs and alternative medicine, however, investigators have failed to identify a safe and effective therapy for patients with NASH. As summarized, the heterogeneity of pathogenic pathways in individual patients with NASH may warrant the development of an individualized treatment according to the underlying pathogenic pathway. The differentiation of pathogenetic targets may require the development of diagnostic and prognostic biomarkers, and the identification of genetic susceptibilities. At present, evidence-based medicine provides only a few options including life-style modifications targeting weight loss, pioglitazone and vitamin E in non-diabetic patients with biopsy-proven NASH.

Gender difference in hepatic steatosis index and lipid accumulation product ability to predict incident metabolic syndrome in the historical cohort of the Brisighella Heart Study

Abstract Background: Nonalcoholic fatty liver disease (NAFLD) and metabolic syndrome are strongly related from both an epidemiological and a pathological point of view. The main aim of our study was to evaluate if two validated indexes of NAFLD are able to predict the 4-year metabolic syndrome incidence in a large population sample of pharmacologically untreated subjects without metabolic syndrome, type 2 diabetes, history of alcohol abuse, or known liver diseases at the baseline.

METHODS

From the database of the Brisighella Heart Study, we selected a subsample of 824 pharmacologically untreated subjects (male, 401; female, 423) without metabolic syndrome, type 2 diabetes, alcohol abuse, or known liver diseases at the 2004 survey and revisited in 2008. The Hepatic Steatosis Index (HSI) and Lipid Accumulation Product (LAP) values were calculated for everyone to evaluate their predictive role for metabolic syndrome through a Cox-regression analysis adjusted by metabolic syndrome components.

RESULTS

We observed 46 new cases of metabolic syndrome (male, 25; female, 21) with a cumulative incidence of 5.6% (1.4% per year): 6.2% in men (1.5% per year), 4.9% in women (1.2% per year). In women, the 4-year metabolic syndrome predictors (R(2)=0.680) were age [odds ratio (OR) 1.13, 95% confidence interval (CI) 1.12-1.15], HSI (OR 1.20, 95% CI 1.15-1.26), and lnLAP (OR 1.16, 95% CI 1.14-1.17), whereas in men they were (R(2)=0.554) age (OR 1.13, 95% CI 1.11-1.14) and lnLAP (OR 1.17, 95% CI 1.15-1.18).

CONCLUSION

HSI and LAP differently predict the 4-year incidence of metabolic syndrome. In women, both indexes can be considered significant predictors, whereas in men only LAP can be considered predictive.

What about non-alcoholic fatty liver disease as a new criterion to define metabolic syndrome?

Non-alcoholic fatty liver disease (NAFLD) is currently not a component of the diagnostic criteria for metabolic syndrome (MetS); however, the development of NAFLD has some common mechanisms with the development of MetS, as they share the pathophysiologic basis of insulin resistance. It is also recognized that NAFLD is the hepatic manifestation of MetS. To define MetS, the presence of at least three of the proposed criteria is required, and sometimes it is sufficient to have only one laboratory value, modified by diet or drugs, for the classification of MetS. Ultrasonographically-detected NAFLD (US-NAFLD) is more stable, only changing during the middle- to long-term. Although controversies over MetS continue, and considering that abdominal ultrasonography for diagnosing NAFLD has high specificity and guidelines to modify the natural course of NAFLD by diet composition or lifestyle have not yet been established, why should we not introduce US-NAFLD as a new criterion to define MetS?

Phase II clinical trial of phlebotomy for non-alcoholic fatty liver disease

BACKGROUND

Elevated iron indices are described in non-alcoholic fatty liver disease and iron reduction has been suggested as a potential therapy.

AIM

To determine whether phlebotomy is an effective therapy for non-alcoholic fatty liver disease.

METHODS

Patients with biopsy proven non-alcoholic fatty liver disease underwent baseline evaluation to determine severity of metabolic and liver disease. A Phase II trial of phlebotomy was carried out to achieve near-iron depletion (serum ferritin ≤50 μg/L or haemoglobin 100 g/L). Repeat liver biopsy, anthropometric and biochemical measurements were performed 6 months following the end of treatment. Primary outcome was improvement in liver histology, assessed using the non-alcoholic fatty liver disease activity score.

RESULTS

Thirty-one patients completed follow-up. Iron reduction resulted in a significant improvement in the non-alcoholic fatty liver disease activity score (-0.74 ± 1.83, P = 0.019). Reductions in individual histological features of lobular inflammation (-0.29 ± 1.07, P = 0.182), steatosis (-0.26 ± 0.82, P = 0.134), hepatocyte ballooning (-0.19 ± 0.70, P = 0.213) did not achieve significance nor did the score for fibrosis (-0.32 ± 0.94, P = 0.099).

CONCLUSIONS

This prospective Phase II study of phlebotomy with paired liver biopsies evaluating phlebotomy therapy in non-alcoholic fatty liver disease patients suggests that iron reduction may improve liver histology. However, the effect size of phlebotomy raises questions of whether treatment could have sufficient clinical significance to justify a definitive Phase III trial. This trial has been registered with the US National Institute of Health (clinicaltrials.gov, Identifier NCT 00641524).

Independent Association between Nonalcoholic Fatty Liver Disease and Cardiovascular Disease: A Systematic Review and Meta-Analysis

Nonalcoholic fatty liver disease (NAFLD) is closely correlated with insulin resistance and several metabolic syndrome features, but whether it could increase the risk of cardiovascular disease remains undefined. To assess the association between NAFLD and the risk of cardiovascular outcomes, we systematically searched the MEDLINE, Embase, and the Cochrane Library database (1947 to October 2012) by using Medical Subject Heading search terms and a standardized protocol. Randomized controlled trials, case-control, and prospective studies carried out in human adults, in which the unadjusted and multivariate adjusted odds ratios with corresponding 95% confidence interval (CI) for cardiovascular disease with NAFLD were reported. The search yielded 4 cross-sectional studies and 2 prospective cohort studies including 7,042 participants. The pooled effects estimate showed that NAFLD was a predictor of cardiovascular disease (odds ratio 1.88, 95% CI, 1.68 to 2.01; P < 0.001). The random effects summary estimate indicated that NAFLD retained a significant association with cardiovascular outcomes independent of conventional risk factors after adjustment for established cardiovascular risk factors (odds ratio 1.50, 95% CI, 1.21 to 1.87; P < 0.001). These results indicate that NAFLD is a strong independent predictor of cardiovascular disease and may play a central role in the cardiovascular risk of metabolic syndrome.

Is nonalcoholic fatty liver disease the hepatic expression of the metabolic syndrome?

Nonalcoholic fatty liver disease (NAFLD) is generally considered as the hepatic manifestation of the metabolic syndrome (MS). Although there is no doubt that NAFLD is tightly linked to the MS, the diagnosis of NAFLD encompasses a broad range of histological entities and as a composite phenotype may be hindering attempts to understand the mechanistic basis of these variants. The awareness that NAFLD is not solely and invariably associated with the MS is a useful means to help direct future studies. We should be aware that mechanisms other than insulin resistance may contribute to the chronic inflammatory processes that underpin the development of liver fat accumulation and the subsequent architectural distortion of the liver. Further studies with special focus on hemoglobin as a risk factor for the development of NAFLD in the absence of MS should be performed.

Serum proteomics for biomarker discovery in nonalcoholic fatty liver disease

Proteomic platforms have gained increasing attention in the clinical spectrum of nonalcoholic fatty liver disease (NAFLD). This approach allows for the unbiased discovery of circulating biochemical markers, i.e., it is not limited to known molecules of presumed importance. This manuscript provides an overview of proteomic serum biomarker discovery in NAFLD. Hemoglobin is currently the most widely replicated proteomic circulating biomarker of NAFLD; it was identified as a biomarker of fatty liver in two distinct proteomic studies and subsequently validated using distinct analytical methods by independent research groups in large replication cohorts. Given the increasing availability of numerous serum samples and the refinement of the technological platforms available to scrutinize the blood proteome, large collaborative studies between academia and industry are warmly encouraged to identify novel, unbiased circulating biomarkers of NAFLD.