Getting closer to a point-of-care diagnostic assessment in patients with chronic liver disease: controlled attenuation parameter for steatosis

Association of the fat mass index with hepatic steatosis and fibrosis: evidence from NHANES 2017-2018

Limited population-based studies discuss the association between fat mass index (FMI) and the risk of liver diseases. This investigation utilized data from the National Health and Nutrition Examination Survey (NHANES) to examine the linkage between the FMI and liver conditions, specifically steatosis and fibrosis. The study leveraged data from NHANES's 2017-2018 cross-sectional study, employing an oversampling technique to deal with sample imbalance. Hepatic steatosis and fibrosis were identified by vibration-controlled transient elastography. Receiver operating curve was used to assess the relationship of anthropometric indicators, e.g., the FMI, body mass index (BMI), weight-adjusted-waist index (WWI), percentage of body fat (BF%), waist-to-hip ratio (WHR), and appendicular skeletal muscle index (ASMI), with hepatic steatosis and fibrosis. In this study, which included 2260 participants, multivariate logistic regression models, stratified analyses, restricted cubic spline (RCS), and sharp regression discontinuity analyses were utilized. The results indicated that the WHR and the FMI achieved the highest area under the curve for identifying hepatic steatosis and fibrosis, respectively (0.720 and 0.726). Notably, the FMI presented the highest adjusted odds ratio for both hepatic steatosis (6.40 [4.91-8.38], p = 2.34e-42) and fibrosis (6.06 [5.00, 7.37], p = 5.88e-74). Additionally, potential interaction effects were observed between the FMI and variables such as the family income-to-poverty ratio, smoking status, and hypertension, all of which correlated with the presence of liver fibrosis (p for interaction < 0.05). The RCS models further confirmed a significant positive correlation of the FMI with the controlled attenuation parameter and liver stiffness measurements. Overall, the findings underscore the strong link between the FMI and liver conditions, proposing the FMI as a potential straightforward marker for identifying liver diseases.

The Role of ElastPQ in Assessing Liver Stiffness for Non-Alcoholic Fatty Liver Disease in Patients Treated with Atypical Antipsychotic Drugs

Objective

To evaluate the role of elastography point quantification (ElastPQ) for the quantitative assessment of stiffness in the fatty liver disease in mental disorder patients and to provide a noninvasive detection method for non-alcoholic fatty liver (NAFLD) caused by atypical antipsychotics drugs (AAPDs).

Methods

A total number of 168 mental disorder patients treated with AAPDs and 58 healthy volunteers were enrolled in this study. All the subjects underwent ultrasound and ElastPQ tests. The basic data of the patients were analyzed.

Results

BMI, liver function, and the value of ElastPQ were considerably higher in the patient group than that in the healthy volunteers. The values of liver stiffness obtained by ElastPQ were increased gradually from 3.48(3.14-3.81) kPa in the normal liver to 8.15(6.44-9.88) in the severe fatty liver. The receiver operating characteristic (ROC) for the diagnosis of fatty liver with ElastPQ were 0.85, 0.79, 0.80, and 0.87 for the diagnosis of normal, mild, moderate, and severe steatosis, respectively, with a sensitive/specificity of 79%/76.4%, 85.7%/78.3%, 86.2%/73%, and 81.3%/82.1%, correspondingly. Moreover, ElastPQ in the olanzapine group was higher than those in the risperidone and aripiprazole groups (5.11(3.83-5.61) kPa vs 4.35(3.63-4.98) kPa, P < 0.05; 5.11(3.83-5.61) kPa vs 4.79(4.18-5.24) kPa, P < 0.05). After one-year treatment, the value of ElastPQ was 4.43(3.85-5.22) kPa, but it was 5.81(5.09-7.33) kPa in patients treated for more than three years. This value increased with treatment prolongation (P < 0.05).

Conclusion

ElastPQ is a real-time, quantitative method for assessing the stiffness of NAFLD. The liver stiffness value could be varied in the different stages of fatty liver. Olanzapine has a considerable influence on liver stiffness. The long-term use of AAPDs can increase the stiffness value of fatty liver.

Ultrasound-Based Diagnostic Methods: Possible Use in Fatty Liver Disease Area

Liver steatosis is a chronic liver disease that is becoming one of the most important global health problems, due to its direct connection with metabolic syndrome, its significant impact on patients' socioeconomic status and frailty, and the occurrence of advanced chronic liver disease. In recent years, there has been rapid technological progress in the ultrasound-based diagnostics field that can help us to quantitatively assess liver steatosis, including continuous attenuation parameters in A and B ultrasound modes, backscatter coefficients (e.g., speed of sound) and ultrasound envelope statistic parametric imaging. The methods used in this field are widely available, have favorable time and financial profiles, and are well accepted by patients. Less is known about their reliability in defining the presence and degree of liver steatosis. Numerous study reports have shown the methods' favorable negative and positive predictive values in comparison with reference investigations (liver biopsy and MRI). Important research has also evaluated the role of these methods in diagnosing and monitoring non-alcoholic fatty liver disease (NAFLD). Since NAFLD is becoming the dominant global cause of liver cirrhosis, and due to the close but complex interplay of liver steatosis with the coexistence of liver fibrosis, knowledge regarding NAFLD's influence on the progression of liver fibrosis is of crucial importance. Study findings, therefore, indicate the possibility of using these same diagnostic methods to evaluate the impact of NAFLD on the patient's liver fibrosis progression risk, metabolic risk factors, cardiovascular complications, and the occurrence of hepatocellular carcinoma. The mentioned areas are particularly important in light of the fact that most of the known chronic liver disease etiologies are increasingly intertwined with the simultaneous presence of NAFLD.

Exosomal FZD-7 Expression Is Modulated by Different Lifestyle Interventions in Patients with NAFLD

Non-alcoholic fatty liver disease (NAFLD) is a multifactorial condition characterized from hypertriglyceridemia and hepatic fat accumulation, in the absence of alcohol intake. NAFLD starts as steatosis (NAFL), and the continued injury relative to the toxic fat induces inflammation, steatohepatitis (NASH), and HCC. One of the factors determining liver degeneration during the evolution of NAFLD is a modification of Wnt/Frizzled (FZD) signaling. In particular, an inhibition of Wnt signaling and an overexpression of a specific FZD receptor protein, namely, the FZD7, have been observed in NAFLD. Actually, the prognosis and the follow-up of NAFLD is not easy, and the liver biopsy is the gold standard for an accurate detection of liver fibrosis. In this study, the modulation of the FZD7 expression levels in plasma-derived exosomes of NAFLD-affected patients, before and after specific lifestyle interventions, were experimentally evaluated by Western blotting analysis. The experimental data were analyzed by an accurate statistical study that indicated, in the exosomes derived from plasma of NAFLD patients with moderate or severe steatosis, an average expression level of FZD7 that was significantly higher than healthy subjects at baseline; conversely, the values were normalized after 90 days of specific lifestyle interventions. The overall results suggested that the FZD7 delivered by exosomes represents a good candidate as a new and effective biomarker for diagnosis and prognosis of NAFLD.

The liver steatosis severity and lipid characteristics in primary biliary cholangitis

Background

Patients with primary biliary cholangitis (PBC) often have comorbid dyslipidemia, and determining the degree of hepatic steatosis can help predict the risk of cardiovascular events in PBC patients. The aim of our study was to analyze the characteristics of lipid distribution and the degree of hepatic steatosis in PBC.

Methods

We retrospectively analyzed 479 cases of PBC, chronic hepatitis B (CHB), chronic hepatitis C (CHC), non-alcoholic fatty liver disease (NAFLD), and healthy subjects (Normal) diagnosed by liver biopsy or definitive clinical diagnosis. Controlled attenuation parameter (CAP) values were applied to assess the degree of steatosis of the liver, and lipid levels were also compared in the five cohorts.

Results

We found that among the five groups of subjects, the PBC group had the lowest CAP values (P < 0.001), and the high-density lipoprotein cholesterol (HDL-C) level in the PBC group was higher than normal, CHC and CHB group (P = 0.004, P = 0.033, P < 0.001, respectively).In the multivariate linear analysis, only BMI (β = 1.280, P = 0.028), ALP (β = − 0.064, P = 0.012), TBA (β = − 0.126, P = 0.020), TG (β = 12.520, P = 0.000), HDL-C (β = − 11.338, P = 0.001) and LDL-C (β = 7.012, P = 0.002) were independent predictors of CAP.

Conclusions

Among PBC, CHB, CHC, NAFLD and healthy subjects, PBC had the lowest degree of hepatic steatosis and higher HDL-C levels, all of which were found to be protective factors against atherosclerosis and cardiovascular risk and would provide a valuable reference for the risk of developing cardiovascular events in PBC patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-021-01974-4.

Controlled attenuation parameter value and the risk of hepatocellular carcinoma in chronic hepatitis B patients under antiviral therapy

BACKGROUND

Controlled attenuation parameter (CAP) can evaluate hepatic steatosis in patients with chronic hepatitis B (CHB). However, prognostic implications of CAP value remain unclear. We evaluated the association between CAP and the risk of hepatocellular carcinoma (HCC) in patients with CHB under antiviral therapy and maintained virologic response.

METHODS

A total of 1823 CHB patients who were taking nucleos(t)ide analogue and showing suppressed hepatitis B virus replication were analyzed. The primary outcome was incident HCC during follow-up. Patients were grouped into those with and without advanced chronic liver disease (ACLD) (liver stiffness measurement cutoff: 10 kPa), and those with and without hepatic steatosis (CAP cutoff: 222 dB/m).

RESULTS

During 6.4 years of follow-up, 127 patients (7.0%) newly developed HCC. Among patients with ACLD (n = 382), the cumulative HCC incidence rate was lower for those with CAP ≥ 222 (11.0% at 5 years) than those with CAP < 222 (24.0% at 5 years, p = 0.002), and was an independent factor associated with HCC. When CAP value was further stratified, the cumulative HCC incidence rate decreased in dose-dependent manner according to an increase in CAP value (24.0%, 13.9%, 12.8% and 6.0% at 5 years for those with CAP < 222, 222-246, 247-273 and ≥ 274, respectively). Among patients without ACLD (n = 1441), there was no significance difference in HCC risk according to CAP value (HCC incidence rate: 3.3% and 4.0% at 5 years for those with CAP < 222 and CAP ≥ 222, p = 0.20).

CONCLUSIONS

Among CHB patients under antiviral therapy showing suppressed HBV replication, low CAP value predicted higher risk for HCC among ACLD patients, indicating that CAP value has a prognostic implication in this population.

Higher cut-off values of non-invasive methods might be needed to detect moderate-to-severe steatosis in morbid obese patients: a pilot study

To evaluate the diagnostic value of described thresholds of controlled attenuation parameter (CAP) and biomarker scores for liver steatosis and to evaluate new cut-offs to detect moderate-to-severe steatosis (S2-3) in patients with morbid obesity. In this prospective study, 32 patients with morbid obesity with indications for bariatric surgery (15 women and 17 men, mean age = 36 years, median BMI = 40.2 kg/m²) underwent CAP, magnetic resonance spectroscopy (MRS), three biomarker scores (Steato-ELSA, Fatty Liver Index (FLI), and Hepatic Steatosis Index (HSI)), and liver biopsy. Subjects were divided into an exploratory cohort (reliable CAP and liver biopsy) and a confirmatory cohort (reliable CAP and MRS) to evaluate new thresholds for CAP and biomarker scores to detect S2-3. Receiver operator characteristic (ROC) curves analyses were performed and the optimal cut-off points were identified using the maximal Youden index. A total of 22 patients had CAP measure and liver biopsy (exploratory cohort) and 24 patients had CAP measure with MRS (confirmatory cohort). New cut-offs were identified for detection of S2-3 by the non-invasive tests using liver biopsy as the reference standard (exploratory cohort). Considering the new proposed cut-offs for detection of S2-3 for CAP (≥ 314 dB/m), Steato-ELSA (≥ 0.832), FLI (≥ 96), and HSI (≥ 53), for the exploratory and confirmatory cohorts sensitivities were: 71-75%, 86-81%, 85-81%, and 71-69% and specificities were: 94-89%, 75-63%, 63-63%, and 75-88%, respectively. Higher cut-offs for CAP and biomarker scores may be better to diagnose moderate-to-severe steatosis in patients with morbid obesity.

Non-alcoholic fatty liver disease and transient elastography

Nonalcoholic fatty liver disease (NAFLD) is a serious condition that can lead to fibrosis, cirrhosis, and hepatocellular carcinoma. NAFLD is associated with metabolic syndrome (MetS) and all of its components. According to data, around 25-30% of population has NAFLD. Giving the growing incidence of MetS, obesity and diabetes mellitus type 2, NAFLD related terminal-stage liver disease is becoming prevailing indication for liver transplantation. In order to prevent terminal stage of this disease, it is crucial to determine those that are in risk group, to modify their risk factors and monitor their potential progression. In the absence of other causes of chronic liver disease, the prime diagnosis of NAFLD in daily clinical practice includes anamnesis, laboratory results (increased levels of aminotransferases and gammaglutamil transferases) and imaging methods. The biggest challenge with NAFLD patients is to differentiate simple steatosis from nonalcoholic steatohepatitis, and detection of fibrosis, that is the main driver in NAFLD progression. The gold standard for NAFLD diagnosis still remains the liver biopsy (LB). However, in recent years many noninvasive methods were invented, such as transient elastography (TE). TE (FibroScan®, Echosens, Paris, France) is used for diagnosis of pathological differences of liver stiffness measurement (LSM) and controlled attenuation parameter (CAP). Investigations in the last years have confirmed that elastographic parameters of steatsis (CAP) and fibrosis (LSM) are reliable biomarkers to non-invasively assess liver steatosis and fibrosis respectively in NAFLD patients. A quick, straightforward and non-invasive method for NAFLD screening in patients with MetS components is TE-CAP. Once diagnosed, the next step is to determine the presence of fibrosis by LSM which should point out high risk patients. Those patients should be referred to hepatologists. LB may be avoided in a substantial number of patients if TE with CAP is used for screening.

Controlled attenuation parameter value-based diagnostic algorithm improves the accuracy of liver stiffness measurement in chronic hepatitis B patients

Liver stiffness measurement (LSM) frequently overestimates the severity of liver fibrosis because of steatosis. However, the impact of the controlled attenuation parameter (CAP) on liver stiffness cutoff values remains unknown; CAP was used to quantify and diagnose the severity of hepatic steatosis. The study was conducted to determine the effect of CAP on liver stiffness cutoff values in chronic hepatitis B (CHB) patients. A retrospective cross-sectional study was performed in liver biopsy-proven CHB patients. The median LSM (kPa) in the elevated CAP group was higher than that in the normal CAP group at the same fibrosis stage. For S2-4, the area under the receiver operating characteristic (AUROC) curve of LSM was 0.78 and 0.72 in the normal and elevated CAP groups, respectively. When a cutoff value of 8.9 kPa was used, the diagnostic accuracy was 77.82% and 63.41% in the normal and elevated CAP groups, respectively. Compared with the alanine transaminase (ALT)-based LSM algorithm, the CAP-based LSM algorithm had a similar correct diagnosis rate (33.64% vs. 33.94%, respectively) but a lower misdiagnosis rate (16.97% vs. 20.30%, respectively). The new CAP-based LSM diagnostic algorithm will improve the diagnostic accuracy of liver fibrosis in CHB patients.

Controlled attenuation parameter reflects steatosis in compensated advanced chronic liver disease

BACKGROUND & AIMS

Controlled attenuation parameter (CAP) for steatosis assessment has not been validated in compensated advanced chronic liver disease compensated advanced chronic liver disease (cACLD). We primarily aimed at assessing the accuracy of CAP for the diagnosis and quantification of steatosis in cACLD. Secondary aim: to assess the validity of non-invasive criteria for cACLD according to liver stiffness measurement (LSM).

METHODS

This is a single-centre retrospective study including patients with cACLD defined as LSM ≥10 kPa, CAP measurement and liver biopsy (reference standard for steatosis and fibrosis) observed in 06/2015-06/2017. Steatosis was graded as S0 (<5%), S1 (5%-32%), S2 (33%-66%) and S3 (>66%). The diagnostic performance of CAP for any grade of steatosis and for high-grade steatosis (≥S2) was studied.

RESULTS

Among 461 consecutive patients, 111 with LSM-based diagnosis of cACLD were included (63% male, median age 55 years, median body mass index 28.1 Kg/m² , aetiology: 32% non-alcoholic fatty liver disease/non-alcoholic steatohepatitis, 32% alcohol or viral + metabolic syndrome, 15% viral, 6% autoimmune, 4% alcohol, 11% others). Median LSM and CAP were 16.1 kPa and 277 dB/m respectively. On liver biopsy, steatosis was found in 88/111 patients (79%); 44 patients (43 with metabolic syndrome) had high-grade steatosis. CAP was accurate in identifying any grade of steatosis (area under the receiving operating characteristic curves 0.847; 95% CI 0.767-0.926, P < .0001), and ≥S2 steatosis (0.860; 95% CI 0.788-0.932, P < .0001). CAP performed similarly in patients with CAP- interquartile range (IQR) ≥ or <40 dB/m.

CONCLUSIONS

Steatosis is frequent in patients with cACLD and metabolic syndrome. CAP diagnostic accuracy for any steatosis and high-grade steatosis is good in this population. A CAP-IQR ≥40 dB/m does not impair CAP diagnostic accuracy in cACLD.

Prospective Comparison of Transient Elastography Using Two Different Devices: Performance of FibroScan and FibroTouch

Purpose

Transient elastography (TE) using FibroScan (FS) has been established to non-invasively assess liver fibrosis and steatosis. The aim of this study was to compare the recently introduced FibroTouch (FT) device with the established FS with respect to liver stiffness and CAP.

Patients and Methods

Thirty-nine patients with and without liver disease were included. All patients were measured three times with FS (FibroScan 530 compact, Echosens, France) and FT (FibroTouch-FT100, Wuxi Hisky Med, China). For FS, M and XL probe were used according to the manufacturer’s specifications. For steatosis, CAP and the comparable FT equivalent UAP (ultrasound attenuation parameter) was determined. Finally, FT and FS were explored in liver tissue-mimicking phantoms.

Results

LS between FS and FT correlated well with r=0.91. Root-mean-square (RMS) of the coefficient of variation for LS was better in FS (11.1% vs 27.4%). Bland-Altman analysis showed a 3.1 kPa mean overestimation of LS by FT. In addition, UAP strongly and linearly depended on the BMI following UAP=3.02 × BMI+186. In phantoms, a similar relation was found with UAP (phantom)= 3.78 × BMI + 146 suggesting that UAP is directly calculated from entered BMI instead of assessing shear-wave attenuation. Consequently, RMS-CV was lower for FT (6.0% vs 9.7%). However, if using different BMI, CV-RMS for FT increased to 12.7%. LS of a patient with manifest liver cirrhosis and ascites was 38.8 kPa using the FS-XL probe but almost normal with FT (7.2 kPa).

Conclusion

Although LS by FT shows good correlation with LS-FS, it has larger variation, continuously overestimates LS and completely fails in ascites. Moreover, FT-UAP seems to be a misleading parameter for steatosis assessment because it is at least in part calculated from mandatory entered patient data. In conclusion, novel LS cut-off values need to be defined for LS-FT and usage of UAP is not recommended.

Effects of Some Food Components on Non-Alcoholic Fatty Liver Disease Severity: Results from a Cross-Sectional Study

Background: The high prevalence of non-alcoholic fatty liver disease (NAFLD) observed in Western countries is due to the concurrent epidemics of overweight/obesity and associated metabolic complications, both recognized risk factors. A Western dietary pattern has been associated with weight gain and obesity, and more recently with NAFLD. Methods: This is a baseline cross-sectional analysis of 136 subjects (79 males) enrolled consecutively in the NUTRIATT (NUTRItion and Ac-TiviTy) study. Study subjects had moderate or severe NAFLD diagnosed by using Fibroscan-CAP. Food Frequency Questionnaire was used to obtain information about food intake. Statistical analysis included descriptive statistics and a multivariable logistic regression model. Results: The mean age was 49.58 (±10.18) with a mean BMI of 33.41 (±4.74). A significant inverse relationship was revealed between winter ice-cream intake and NAFLD severity (O.R. 0.65, 95% C.I. 0.95–0.99); chickpeas intake and NAFLD severity (O.R. 0.57, 95% C.I. 0.34–0.97), and not industrial aged-cheeses type (O.R. 0.85, 95% C.I. 0.74–0.98). A statistically significant positive association also emerged between rabbit meat (O.R. 1.23, 95% C.I. 1.01–1.49), industrial type aged cheeses (O.R. 1.17, 95% C.I. 1.01–1.35), milk-based desserts (no winter ice cream) (O.R. 1.11, 95% C.I. 1.01–1.21), fats (O.R. 1.12, 95% C.I. 1.01–1.25), and NAFLD severity. Conclusion: The fresh foods from non-intensive farming and high legume intake that characterize the Mediterranean diet would seem to be beneficial for patients with NAFLD.

A review of the use of transient elastography in the assessment of fibrosis and steatosis in the post-liver transplant patient

Liver biopsy is considered the gold standard method for diagnosing and staging liver disease, particularly in the post-liver transplant setting. Given the invasive nature of biopsy, alternate means for accurately assessing liver fibrosis and steatosis are preferred especially as the number of patients with fatty liver disease is increasing. Transient elastography has been validated as a useful tool for evaluation of liver fibrosis, as has controlled attenuation parameter index as a tool for assessing steatosis. It is a non-invasive, rapid, and highly reproducible approach to demonstrate the presence of fibrosis among non-transplant patients with chronic liver disease of various etiologies. However, it has not yet found wide acceptance in liver transplant recipients. There are few published studies evaluating the merits and applicability of transient elastography to assess allografts after liver transplantation. We review the published data on the use of transient elastography with concurrent controlled attenuation parameter in liver transplant recipients and recommend its greater use to follow allograft function over time.

Prospective Evaluation of Hepatic Steatosis Using Ultrasound Attenuation Imaging in Patients with Chronic Liver Disease with Magnetic Resonance Imaging Proton Density Fat Fraction as the Reference Standard

The purpose of our study was to investigate the diagnostic performance of 2-D ultrasound attenuation imaging (ATI) for the assessment of hepatic steatosis in patients with chronic liver disease using magnetic resonance imaging proton density fat fraction (MRI-PDFF) as the reference standard. We prospectively analyzed 87 patients with chronic liver disease who had reliable measurements at both ATI and MRI-PDFF. For the detection of hepatic steatosis of MRI-PDFF ≥5% and MRI-PDFF ≥10%, ATI measurements yielded areas under the receiver operating characteristic curve of 0.76 and 0.88, respectively (95% confidence intervals: 0.66-0.85 and 0.79-0.94). Attenuation coefficients at ATI were moderately correlated with MRI-PDFF (ρ = 0.66). In conclusion, attenuation coefficients at ultrasound ATI were well correlated with MRI-PDFF and, thus, may provide good diagnostic performance in the assessment of hepatic steatosis, making these coefficients a promising tool for the non-invasive assessment and quantification of hepatic steatosis.

The B-Mode Image-Guided Ultrasound Attenuation Parameter Accurately Detects Hepatic Steatosis in Chronic Liver Disease

The purpose of our study was to evaluate the diagnostic accuracy of the ultrasound-guided attenuation parameter (UGAP) for the detection of hepatic steatosis in comparison with the controlled attenuation parameter (CAP), using histopathology as the reference standard. We prospectively analyzed 163 consecutive chronic liver disease patients who underwent UGAP, CAP, computed tomography and a liver biopsy on the same day between April 2016 and July 2017. Radiofrequency signals corresponding to the images were compensated by the reference signal previously measured from the uniform phantom with known attenuation (0.44 dB/cm/MHz). The attenuation coefficient was calculated from the signals' decay slope. The median attenuation coefficient values in patients with S0 (n = 62), S1 (n = 63), S2 (n = 23) and S3 grade (n = 15) were 0.485, 0.560, 0.660 and 0.720, respectively. Significant correlations were found between attenuation coefficient and percentage steatosis, CAP values and liver-to-spleen computed tomography attenuation ratio (p < 0.001). The areas under the receiver operating characteristic curve of UGAP for identifying ≥S1, ≥S2 and ≥S3 were 0.900, 0.953 and 0.959, respectively, which were significantly better than the results obtained with CAP for identifying ≥S2 and ≥S3. In conclusion, UGAP had high diagnostic accuracy for detecting hepatic steatosis in patients with chronic liver disease.

Prevalence of hepatic steatosis as assessed by controlled attenuation parameter (CAP) in subjects with metabolic risk factors in primary care. A population-based study

Background

Primary care is the ideal setting for early identification of patients with non-alcoholic fatty liver disease (NAFLD). NAFLD is a potentially progressive disease that may lead to cirrhosis and liver cancer but is frequently underrecognized because subjects at risk are often not evaluated. Controlled attenuation parameter (CAP) is a reliable method for non-invasive quantification of liver fat. It has the advantage of simultaneous measurement of liver stiffness (LS), an estimate of liver fibrosis. There is no information on CAP in subjects with risk factors from primary care.

Aim

To investigate the prevalence of hepatic steatosis, as estimated by CAP, in subjects from the community with metabolic risk factors and correlate findings with clinical and biochemical characteristics and LS.

Patients and methods

Population-based study of 215 subjects with metabolic risk factors without known liver disease identified randomly from a primary care center. A control group of 80 subjects matched by age and sex without metabolic risk factors was also studied. CAP and LS were assessed using Fibroscan.

Results

Subjects with risk factors had CAP values higher than those of control group (268±64 vs 243±49dB/m,p<0.001). Prevalence of severe steatosis (CAP> 280dB/m) in subjects with risk factors was 43%. In multivariate analysis, fatty liver index (FLI) and HOMA were independent predictive factors of severe steatosis. There was a direct correlation between CAP and FLI values (r = 0.52,p<0.001). Interestingly, prevalence of increased LS was 12.6% in the risk group vs 0% in the control group (p<0.001). Increased LS occurred predominantly in subjects with high CAP values.

Conclusions

A high proportion of subjects with metabolic risk factors seen in primary care have severe steatosis. FLI could be used as a surrogate of CAP. Increased LS was found in a significant proportion of subjects with risk factors but not in control subjects.

Aerobic Physical Activity and a Low Glycemic Diet Reduce the AA/EPA Ratio in Red Blood Cell Membranes of Patients with NAFLD

Omega-6 Polyunsaturated Fatty Acids (PUFAs), through the eicosanoids derived from arachidonic acid (AA), are able to modulate the inflammatory processes, whereas omega-3 PUFAs, such as eicosapentaenoic acid (EPA), exert anti-oxidant and anti-inflammatory effects. An unbalanced AA/EPA ratio in favor of AA leads to the development of different metabolic disorders, including non-alcoholic fatty liver disease (NAFLD). The aim of the present study was to evaluate the effects of different diets, alone and in combination with two physical activity programs, on the AA/EPA ratio value in erythrocyte membranes of patients with NAFLD. One hundred forty-two subjects with NAFLD were enrolled in the study and randomized into six treatment groups. AA/EPA ratio was significantly reduced after 90 days of treatment with only a program of aerobic activity. However, it appears that the combination of physical activity and a Low Glycemic Index Mediterranean Diet (LGIMD) was more efficacious in reducing AA/EPA levels, at 45 days of treatment, even if this effect was not maintained over time. The combined effect of diet and physical activity reduced the AA/EPA ratio value improving the score of steatosis. Dietary intake of omega-3 PUFAs, in association with a healthy lifestyle, may be used in the prevention protocols for many chronic diseases, including NAFLD.

Prognostic Significance of Controlled Attenuation Parameter in Patients With Compensated Advanced Chronic Liver Disease

Obesity and steatosis have been associated with liver disease progression in patients with compensated advanced chronic liver disease (cACLD) (liver stiffness measurement [LSM] ≥ 10 kPa). The controlled attenuation parameter (CAP) estimates steatosis during LSM by transient elastography. We aimed to evaluate whether CAP is associated with the development of clinically relevant events in cACLD. Consecutive patients with cACLD and CAP measurements observed between September 2013 and September 2015 were retrospectively studied. Classical decompensation and severe bacterial infections on follow-up were recorded. A predefined CAP cut-off for steatosis was used (220 dB/m; 90% sensitivity). The association among LSM, CAP, and events was assessed by univariate and multivariate Cox regression. Among the 193 patients (viral etiology = 58%; median Child score = 5; LSM = 15.1 kPa; CAP = 255 ± 62 dB/m) who were followed up in median for 18 months, 18 developed clinically relevant events (11 liver decompensation, 7 severe bacterial infections). Patients developing events had higher LSM (median: 30.8 versus 14.3 kPa, P < 0.001) and showed trends for higher CAP (275 ± 46 versus 252 ± 63 dB/m, P = 0.07), lower platelet count (134 ± 74 versus 167 ± 74 G/L, P = 0.07), and worse liver function versus patients remaining compensated. Body mass index was similar in the two groups. All events were more frequent in patients with CAP being greater than or equal to 220 dB/m (12.9% versus 1.6% in CAP < 220; P = 0.013), and 10 of 11 episodes of liver decompensation occurred in patients with CAP being greater than or equal to 220 dB/m. Following multivariate analysis, LSM and CAP greater than or equal to 220 dB/m remained independently associated with clinical events in the whole population and in patients with clinically significant portal hypertension. Conclusion: The CAP being greater than or equal to 220 dB/m is associated with increased risk of clinical decompensation and bacterial infections independent of LSM in patients with cACLD and allows refining the noninvasive risk stratification in this population. (Hepatology Communications 2018; 00:000-000).

Impact of controlled attenuation parameter on detecting fibrosis using liver stiffness measurement

BACKGROUND

Liver fibrosis is often accompanied by steatosis, particularly in patients with non-alcoholic fatty liver disease (NAFLD), and its non-invasive characterisation is of utmost importance. Vibration-controlled transient elastography is the non-invasive method of choice; however, recent research suggests that steatosis may influence its diagnostic performance. Controlled Attenuation Parameter (CAP) added to transient elastography enables simultaneous assessment of steatosis and fibrosis.

AIM

To determine how to use CAP in interpreting liver stiffness measurements.

METHODS

This is a secondary analysis of data from an individual patient data meta-analysis on CAP. The main exclusion criteria for the current analysis were unknown aetiology, unreliable elastography measurement and data already used for the same research question. Aetiology-specific liver stiffness measurement cut-offs were determined and used to estimate positive and negative predictive values (PPV/NPV) with logistic regression as functions of CAP.

RESULTS

Two thousand and fifty eight patients fulfilled the inclusion criteria (37% women, 18% NAFLD/NASH, 42% HBV, 40% HCV, 51% significant fibrosis ≥ F2). Youden optimised cut-offs were only sufficient for ruling out cirrhosis (NPV of 98%). With sensitivity and specificity-optimised cut-offs, NPV for ruling out significant fibrosis was moderate (70%) and could be improved slightly through consideration of CAP. PPV for significant fibrosis and cirrhosis were 68% and 55% respectively, despite specificity-optimised cut-offs for cirrhosis.

CONCLUSIONS

Liver stiffness measurement values below aetiology-specific cut-offs are very useful for ruling out cirrhosis, and to a lesser extent for ruling out significant fibrosis. In the case of the latter, Controlled Attenuation Parameter can improve interpretation slightly. Even if cut-offs are very high, liver stiffness measurements are not very reliable for ruling in fibrosis or cirrhosis.

Novel ultrasound-based methods to assess liver disease: The game has just begun

In the last 10 years the availability of ultrasound elastography allowed to diagnose and stage liver fibrosis in a non-invasive way and changed the clinical practice of hepatology. Newer ultrasound-based techniques to evaluate properties of the liver tissue other than fibrosis are emerging and will lead to a more complete characterization of the full spectrum of diffuse and focal liver disease. Since these methods are currently undergoing validation and go beyond elastography for liver tissue evaluation, they were not included in the recent guidelines regarding elastography issued by the European Federation of Societies in Ultrasound in Medicine and Biology. In this review paper, we outline the major advances in the field of ultrasound for liver applications, with special emphasis on techniques that could soon be part of the future armamentarium of ultrasound specialists devoted to the assessment of liver disease. Specifically, we discuss current and future ultrasound assessment of steatosis, spleen stiffness for portal hypertension, and elastography for the evaluation of focal liver lesions; we also provide a short glimpse into the next generation of ultrasound diagnostic methods.

Significant decrease of saturation index in erythrocytes membrane from subjects with non-alcoholic fatty liver disease (NAFLD)

Background

The lipidomic profiling of erythrocyte membranes is expected to provide a peculiar scenario at molecular level of metabolic and nutritional pathways which may influence the lipid balance and the adaptation and homeostasis of the organism. Considering that lipid accumulation in the cell is important in promoting tissue inflammation, the purpose of this study is to analyze the fatty acid profile in red blood cell membranes of patients with Non-Alcoholic Fatty Liver Disease (NAFLD), in order to identify and validate membrane profiles possibly associated with the degree of hepatic damage.

Methods

This work presents data obtained at baseline from 101 subjects that participated to a nutritional trial (registration number: NCT02347696) enrolling consecutive subjects with NAFLD. Diagnosis of liver steatosis was performed by using vibration-controlled elastography implemented on FibroScan. Fatty acids, extracted from phospholipids of erythrocyte membranes, were quantified by gas chromatography method.

Results

The subjects with severe NAFLD showed a significant decrease of the ratio of stearic acid to oleic acid (saturation index, SI) compared to controls, 1.281 ± 0.31 vs 1.5 ± 0.29, respectively. Low levels of SI in red blood cell membranes, inversely associated with degree of liver damage, suggest that an impairment of circulating cell membrane structure can reflect modifications that take place in the liver. Subjects with severe NAFLDalso showed higher levels of elongase 5 enzymatic activity, evaluated as vaccenic acid to palmitoleic acid ratio.

Conclusions

Starting from these evidences, our findings show the importance of lipidomic approach in the diagnosis and the staging of NAFLD.

A comparison of hepatic steatosis index, controlled attenuation parameter and ultrasound as noninvasive diagnostic tools for steatosis in chronic hepatitis B

AIMS

To evaluate the value of noninvasive tools for diagnosis of hepatic steatosis in patients with chronic hepatitis B (CHB).

METHODS

Consecutive treatment-naïve patients with CHB with body mass index less than 30kg/m² who underwent liver biopsy, ultrasound and FibroScan^® were enrolled. The diagnostic performance of controlled attenuation parameter (CAP), hepatic steatosis index (HSI) and ultrasound for hepatic steatosis compared with liver biopsy was assessed. The areas under receiver operating characteristics curves (AUROCs) were calculated to determine the diagnostic efficacy, with comparisons using the DeLong test.

RESULTS

CAP and HSI accuracies were significantly higher than that of ultrasound to detect patients with biopsy-proven mild steatosis (S1, 65.3%, 56.5%, respectively, vs. 17.7%, χ²=46.305, 31.736, both P<0.05)and moderate-severe (S2-3) steatosis (92.3%, 100%, respectively, vs. 53.8%, χ²=4.887, 7.800, P=0.037, 0.007, respectively). Both CAP and HSI had lower underestimation rates of steatosis grade than ultrasound (12%, 14.8%, respectively, vs. 29.5%, χ²=9.765, 6.452; P<0.05 for both), but they exhibited higher overestimation rates (30.5%, 38.2%, respectively, vs. 12.4%, χ²=39.222, 70.986; both P<0.05). The AUROCs of CAP and HSI were 0.780 (95% confidence intervals [CIs] 0.735-0.822) and 0.655 (95%CI 0.604-0.704) for S ≥1, 0.932 (95%CI 0.902-0.956) and 0.755 (95%CI 0.707-0.799) for S ≥2, 0.990 (95%CI 0.974-0.998) and 0.786 (95% CI 0.740-0.827) for S3, respectively.

CONCLUSION

CAP might be more accurate for detecting hepatic steatosis than HSI and ultrasound in patients with CHB, but further studies are needed to reduce the overestimation rates.

Individual patient data meta-analysis of controlled attenuation parameter (CAP) technology for assessing steatosis

BACKGROUND & AIMS

The prevalence of fatty liver underscores the need for non-invasive characterization of steatosis, such as the ultrasound based controlled attenuation parameter (CAP). Despite good diagnostic accuracy, clinical use of CAP is limited due to uncertainty regarding optimal cut-offs and the influence of covariates. We therefore conducted an individual patient data meta-analysis.

METHODS

A review of the literature identified studies containing histology verified CAP data (M probe, vibration controlled transient elastography with FibroScan®) for grading of steatosis (S0-S3). Receiver operating characteristic analysis after correcting for center effects was used as well as mixed models to test the impact of covariates on CAP. The primary outcome was establishing CAP cut-offs for distinguishing steatosis grades.

RESULTS

Data from 19/21 eligible papers were provided, comprising 3830/3968 (97%) of patients. Considering data overlap and exclusion criteria, 2735 patients were included in the final analysis (37% hepatitis B, 36% hepatitis C, 20% NAFLD/NASH, 7% other). Steatosis distribution was 51%/27%/16%/6% for S0/S1/S2/S3. CAP values in dB/m (95% CI) were influenced by several covariates with an estimated shift of 10 (4.5-17) for NAFLD/NASH patients, 10 (3.5-16) for diabetics and 4.4 (3.8-5.0) per BMI unit. Areas under the curves were 0.823 (0.809-0.837) and 0.865 (0.850-0.880) respectively. Optimal cut-offs were 248 (237-261) and 268 (257-284) for those above S0 and S1 respectively.

CONCLUSIONS

CAP provides a standardized non-invasive measure of hepatic steatosis. Prevalence, etiology, diabetes, and BMI deserve consideration when interpreting CAP. Longitudinal data are needed to demonstrate how CAP relates to clinical outcomes.

LAY SUMMARY

There is an increase in fatty liver for patients with chronic liver disease, linked to the epidemic of the obesity. Invasive liver biopsies are considered the best means of diagnosing fatty liver. The ultrasound based controlled attenuation parameter (CAP) can be used instead, but factors such as the underlying disease, BMI and diabetes must be taken into account. Registration: Prospero CRD42015027238.

Coffee Intake Is Associated with a Lower Liver Stiffness in Patients with Non-Alcoholic Fatty Liver Disease, Hepatitis C, and Hepatitis B

There is emerging evidence for the positive effects or benefits of coffee in patients with liver disease. We conducted a retrospective cross-sectional study on patients with non-alcoholic fatty liver disease (NAFLD), hepatitis C virus (HCV), and hepatitis B virus (HBV) infection to determine the effects of coffee intake on a non-invasive marker of liver fibrosis: liver stiffness assessed by transient elastography (TE). We assessed coffee and tea intake and measured TE in 1018 patients with NAFLD, HCV, and HBV (155 with NAFLD, 378 with HCV and 485 with HBV). Univariate and multivariate regression models were performed taking into account potential confounders. Liver stiffness was higher in males compared to females (p < 0.05). Patients with HBV had lower liver stiffness than those with HCV and NAFLD. After adjustment for age, gender, smoking, alcohol consumption, M or XL probe, and disease state (NAFLD, HCV, and HBV status), those who drank 2 or more cups of coffee per day had a lower liver stiffness (p = 0.044). Tea consumption had no effect (p = 0.9). Coffee consumption decreases liver stiffness, which may indicate less fibrosis and inflammation, independent of disease state. This study adds further evidence to the notion of coffee maybe beneficial in patients with liver disease.

Short-Term Hypocaloric High-Fiber and High-Protein Diet Improves Hepatic Steatosis Assessed by Controlled Attenuation Parameter

OBJECTIVES

Non-alcoholic fatty liver disease is one of the most prevalent liver diseases and increases the risk of fibrosis and cirrhosis. Current standard treatment focuses on lifestyle interventions. The primary aim of this study was to assess the effects of a short-term low-calorie diet on hepatic steatosis, using the controlled attenuation parameter (CAP) as quantitative tool.

METHODS

In this prospective observational study, 60 patients with hepatic steatosis were monitored during a hypocaloric high-fiber, high-protein diet containing 1,000 kcal/day. At baseline and after 14 days, we measured hepatic fat contents using CAP during transient elastography, body composition with bioelectrical impedance analysis, and serum liver function tests and lipid profiles using standard clinical-chemical assays.

RESULTS

The median age was 56 years (25-78 years); 51.7% were women and median body mass index was 31.9 kg/m(2) (22.4-44.8 kg/m(2)). After 14 days, a significant CAP reduction (14.0%; P<0.001) was observed from 295 dB/m (216-400 dB/m) to 266 dB/m (100-353 dB/m). In parallel, body weight decreased by 4.6% (P<0.001), of which 61.9% was body fat. In addition, liver stiffness (P=0.002), γ-GT activities, and serum lipid concentrations decreased (all P<0.001).

CONCLUSIONS

This study shows for the first time that non-invasive elastography can be used to monitor rapid effects of dietary treatment for hepatic steatosis. CAP improvements occur after only 14 days on short-term low-calorie diet, together with reductions of body composition parameters, serum lipids, and liver enzymes, pointing to the dynamics of hepatic lipid turnover.

Estimating steatosis and fibrosis: Comparison of acoustic structure quantification with established techniques

AIM: To compare ultrasound-based acoustic structure quantification (ASQ) with established non-invasive techniques for grading and staging fatty liver disease.

METHODS: Type 2 diabetic patients at risk of non-alcoholic fatty liver disease (n = 50) and healthy volunteers (n = 20) were evaluated using laboratory analysis and anthropometric measurements, transient elastography (TE), controlled attenuation parameter (CAP), proton magnetic resonance spectroscopy (¹H-MRS; only available for the diabetic cohort), and ASQ. ASQ parameters mode, average and focal disturbance (FD) ratio were compared with: (1) the extent of liver fibrosis estimated from TE and non-alcoholic fatty liver disease (NAFLD) fibrosis scores; and (2) the amount of steatosis, which was classified according to CAP values.

RESULTS: Forty-seven diabetic patients (age 67.0 ± 8.6 years; body mass index 29.4 ± 4.5 kg/m²) with reliable CAP measurements and all controls (age 26.5 ± 3.2 years; body mass index 22.0 ± 2.7 kg/m²) were included in the analysis. All ASQ parameters showed differences between healthy controls and diabetic patients (P < 0.001, respectively). The ASQ FD ratio (logarithmic) correlated with the CAP (r = -0.81, P < 0.001) and ¹H-MRS (r = -0.43, P = 0.004) results. The FD ratio [CAP < 250 dB/m: 107 (102-109), CAP between 250 and 300 dB/m: 106 (102-114); CAP between 300 and 350 dB/m: 105 (100-112), CAP ≥ 350 dB/m: 102 (99-108)] as well as mode and average parameters, were reduced in cases with advanced steatosis (ANOVA P < 0.05). However, none of the ASQ parameters showed a significant difference in patients with advanced fibrosis, as determined by TE and the NAFLD fibrosis score (P > 0.08, respectively).

CONCLUSION: ASQ parameters correlate with steatosis, but not with fibrosis in fatty liver disease. Steatosis estimation with ASQ should be further evaluated in biopsy-controlled studies.

Usefulness of liver test and controlled attenuation parameter in detection of nonalcoholic fatty liver disease in patients with chronic renal failure and coronary heart disease

BACKGROUND

In recent years, nonalcoholic fatty liver disease (NAFLD) was recognized as an important factor in chronic kidney disease (CKD) pathogenesis. The concentrations of serum aminotransferases in both chronic dialysis and chronic renal failure (CRF) patients most commonly fall within the lower end of the range of normal values. The aim of the present study was to investigate the usefulness of four liver tests and four biological scores in detection of NAFLD in comparison with transient elastography (TE) findings in different groups of patients.

METHODS

The study was cross-sectional analysis collected data from a single tertiary care center. Of 202 patents there were 52 patients with CKD, 50 patients with end-stage renal disease (ESRD) treated with haemodialysis (HD), 50 renal transplant recipients (RTRs) and 50 patients with proven coronary heart disease (CHD). Fifty sex- and age-matched individuals without NAFLD and with normal liver and kidney function tests served as controls. With the help of TE (FibroScan®, Echosense SA, Paris, France), liver stiffness was selected as the parameter to quantify liver fibrosis and Controlled Attenuation Parameter (CAP) was used to detect and quantify liver steatosis.

RESULTS

According to the CAP findings 76.9 %CKD patients, 82 %HD patients, 74 %RTRs and 69.1 % CHD patients had CAP > 238 dB.m(-1) and thus by definition NAFLD. We have found that ALT, AST and GGT levels were positively correlated with CAP values while ALT and AST showed positive correlation with liver stiffness acquired with TE only in CHD patients. According to TE findings APRI (AUC 0.796) and FIB-4 (AUC 0.790) scores were correlated with the presence of fibrosis, while HIS score was correlated with the presence of steatosis (AUC 0.867) only in CHD patients.

CONCLUSION

Liver tests and biological scores are not useful for NAFLD detection in CRF patients. TE with CAP provides the opportunity of noninvasive screening for NAFLD as well as liver fibrosis in patients with CRF.

Noninvasive characterization of graft steatosis after liver transplantation

OBJECTIVE

Liver graft steatosis has not been noninvasively evaluated yet. We therefore characterized liver transplant recipients by transient elastography (TE) and controlled attenuation parameter (CAP) and correlated the results with clinical and genetic risk factors.

METHODS

A total of 204 patients (pretransplant disease: n = 102 nonalcoholic etiology, nonalcoholic liver cirrhosis (non-ALC); n = 102 alcoholic liver disease, ALC; 42% female; median age 57.8 years; median time since transplantation 66 months) underwent ultrasound, TE, CAP, and nonalcoholic fatty liver disease (NAFLD) fibrosis score. Recipient DNA samples were genotyped for patatin-like phospholipase domain-containing protein 3 (PNPLA3) (rs738409) and IL28B (rs8099917, rs12979860) polymorphisms.

RESULTS

Increased hepatic echogenicity at ultrasound was observed in 36% of patients, CAP values >252 and >300 dB/m indicated steatosis and advanced steatosis in 44% and 24% of individuals. Advanced fibrosis (TE >7.9 kPa) was associated with increased CAP results (266 vs. 229 dB/m, p = 0.012). PNPLA3 G-allele carriers had increased CAP values (257 vs. 222 dB/m, p = 0.032), higher liver stiffness (TE 6.4 vs. 5.5 kPa, p = 0.005), and prevalence of diabetes mellitus (40% vs. 22%, p = 0.016). No such association was observed for IL28B polymorphisms. ALC compared to non-ALC patients had higher body mass index (28.1 vs. 25.5 kg/m², p < 0.001), higher prevalence of diabetes mellitus (41% vs. 25%, p = 0.017), and PNPLA3 CG + GG genotype (73% vs. 47%, p = 0.006), and had elevated TE (6.3 vs. 5.4 kPa, p = 0.022), CAP (266 vs. 221 dB/m, p = 0.001), and NAFLD fibrosis score (score -0.5 vs. -1.3, p < 0.001).

CONCLUSION

Modern noninvasive liver graft assessment frequently detects hepatic steatosis, which is associated with graft fibrosis, components of the metabolic syndrome and recipient PNPLA3 rs738409 genotype, especially in ALC patients.