Prediction of Nonalcoholic Fatty Liver Disease Using Noninvasive and Non-Imaging Procedures in Japanese Health Checkup Examinees

Metabolic outcomes in non-alcoholic and alcoholic steatotic liver disease among Korean and American adults

BACKGROUND

This study investigated the prevalence and causal relationships of chronic metabolic diseases (diabetes, hypertension, and dyslipidemia) with steatotic liver disease (SLD), specifically metabolically associated alcoholic liver disease (MetALD).

METHODS

We conducted a comprehensive analysis using cross-sectional data from the KNHANES from 2011 to 2021 and the NHANES from 1999 to 2020. Longitudinal data from 2001 to 2014 from the KoGES were used. Participants were categorized into the metabolic dysfunction-associated SLD(MASLD), MetALD, and ALD groups based on their hepatic steatosis index (HSI), including liver profiles, body composition, and diabetes, and alcohol consumption. Multivariable, including age and smoking status, logistic and Cox regression analyses were performed to assess the prevalence and incidence of chronic diseases.

RESULTS

In both the KNHANES and NHANES cohorts, an increased HSI was significantly associated with a higher prevalence of chronic metabolic diseases. Longitudinal data from the KoGES cohort showed that MASLD and MetALD were significant predictors of chronic metabolic disease in both men and women. MetALD showed a higher hazard ratio for the development of chronic metabolic diseases than MASLD in Cox regression analysis.

CONCLUSIONS

This study highlighted the intertwined nature of SLD and metabolic health, with an emphasis on the role of MetALD. The significant association between MetALD and chronic metabolic diseases underscores the need for integrated management strategies that address both liver health and metabolic risk factors.

Association between surrogate indices of fatty liver and the risk of colorectal cancer: a cross-sectional United States study

BACKGROUND

The presence of fatty liver (FL) has been suggested to influence the incidence of colorectal cancer (CRC). This study aimed to evaluate the predictive utility of six alternative indices of FL-namely, liver fat percentage (PLF), lipid accumulation product (LAP), hepatic steatosis index (HSI), United States fatty liver index (USFLI), fatty liver index (FLI), and Zhejiang University index (ZJU)-in assessing the risk of CRC. We aimed to determine their effectiveness in predicting CRC risk by comparing these surrogate indices.

METHODS

Data for this study were derived from the National Health and Nutrition Examination Survey (NHANES) conducted between 2003 and 2018, focusing on adults over 20 years old. The six FLIs were calculated using established methodologies outlined in prior research. To identify key variables, the Boruta algorithm was employed. The relationships between FLIs and CRC risk were assessed using multivariable logistic regression, generalized linear models (GLMs), and restricted cubic spline (RCS) models. Additionally, subgroup analyses were performed to investigate the effects of potential confounders.

RESULTS

Among the 16,250 individuals surveyed, 96 were diagnosed with CRC. Those with CRC exhibited significantly higher levels of PLF (4.65 vs. 3.31, P=0.004), LAP (55.63 vs. 42.34, P=0.04), USFLI (23.22 vs. 17.83, P<0.001), and FLI (58.16 vs. 50.86, P=0.048) compared to individuals without CRC. Multivariate logistic regression and RCS analyses indicated that, of the six indices, only USFLI was significantly associated with an increased risk of CRC. Notably, further stratification of USFLI revealed that this association was consistently stronger in individuals aged over 65 years [odds ratio (OR) =1.023; 95% confidence interval (CI): 1.005-1.041; P=0.01] and among non-smokers (OR =1.018; 95% CI: 1.003-1.033; P=0.02) after adjusting for multiple confounders.

CONCLUSIONS

The USFLI index demonstrated a more significant association with the risk of CRC compared to the other five alternative FLIs, highlighting its potential utility in predicting CRC risk in clinical settings.

The Effects of Oral Semaglutide on Hepatic Fibrosis in Subjects with Type 2 Diabetes in Real-World Clinical Practice: A Post Hoc Analysis of the Sapporo-Oral SEMA Study

BACKGROUND/OBJECTIVES

Metabolic dysfunction-associated steatotic liver disease (MASLD) is an important common comorbidity in subjects with type 2 diabetes, and liver fibrosis is a factor directly related to its prognosis. Glucagon-like peptide-1 receptor agonists are useful treatment options for MASLD; however, the efficacy of oral semaglutide in treating liver steatosis/fibrosis has not been fully elucidated.

METHODS

A secondary analysis of a multicenter, retrospective, observational study investigating the efficacy and safety of oral semaglutide in Japanese subjects with type 2 diabetes in a real-world clinical setting (the Sapporo-Oral SEMA study) was conducted. Subjects in the original cohort were divided into groups as follows: subjects with suspected MASLD (alanine aminotransferase > 30 U/L) were placed in an overall group; a subpopulation from an overall group at high risk for hepatic fibrosis (fibrosis-4 (FIB-4) index ≥ 1.3 or platelet count < 200,000/µL) was placed in a high-risk group; and the remaining subjects were placed in a low-risk group. Changes in the hepatic steatosis index and FIB-4 index after oral semaglutide induction were explored using a paired t-test or the Wilcoxon signed-rank test.

RESULTS

Overall, 169 subjects (including 131 that switched from other medications) were analyzed, and 67 and 102 subjects were selected for the high-risk and low-risk groups, respectively. Oral semaglutide significantly improved the hepatic steatosis index (from 46.1 to 44.6, p < 0.001) and FIB-4 index (from 1.04 to 0.96, p < 0.001) as well as several metabolic parameters in all cohorts. The efficacy of semaglutide in treating liver fibrosis was confirmed by the addition of, and switching from, existing agent groups. Furthermore, improvement in the FIB-4 index was significantly negatively correlated with the baseline FIB-4 index.

CONCLUSIONS

The induction of oral semaglutide might be a useful treatment option for subjects with type 2 diabetes at high risk for liver fibrosis, even when switching from conventional medications for diabetes.

Dietary Patterns Rich in Soybean Products, Vegetables, Fish, Fruits, and Miso Soup Were Inversely Associated with Fatty Liver Index: The Nagahama Study

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a prominent liver disease occurring in approximately 25% of the general population. As treatment, lifestyle modification is essential, but there are few reports on dietary patterns associated with MASLD except for the Mediterranean diet. This study examines dietary habits related to MASLD using the fatty liver index (FLI). Longitudinal analysis of a community-based cohort, the Nagahama Prospective Cohort for Comprehensive Human Bioscience, was performed. Dietary habits were assessed by a self-reported questionnaire on food intake frequency, and factor analysis was applied to identify dietary patterns. Multiple regression analysis was performed with baseline FLI or FLI after 5 y as the dependent variable and sex, age, and/or baseline FLI, and factor scores of each dietary pattern as simultaneous independent variables. The same analyses stratified by sex or body mass index (BMI) were also performed. Three thousand five hundred one participants were included. The 15 food items of the questionnaire were summarized into four dietary patterns. Dietary patterns rich in soybean products, vegetables, fish, fruits, and miso soup, which is characteristic of traditional Japanese diet, negatively correlated with FLI and FLI after 5 y (partial regression coefficient: -3.01 and -1.03, respectively; p<0.01 for both). The result was similar in sex-specific analysis and in BMI<23 kg/m2 group, when the participants were stratified according to BMI. Our results suggest that dietary patterns rich in soybean products, vegetables, fish, fruits, and miso soup are protective factors against MASLD especially in individuals with BMI<23 kg/m2.

High levels of serum dihomo-γ-linolenic acid are associated with non-alcoholic fatty liver disease in type 2 diabetic patients

An elevated level of saturated fatty acids (SFAs) can cause non-alcoholic fatty liver disease (NAFLD). While n-3 polyunsaturated fatty acids (PUFAs) were shown to improve NAFLD, the effects of n-6 PUFAs in the liver have not been fully elucidated. We examined the association between NAFLD and n-6 PUFAs, particularly dihomo-γ-linolenic acid (DGLA), in patients with type 2 diabetes. A total of 60 patients with type 2 diabetes were included in the study. Patients were categorized into the NAFLD group (n = 35) and non-NAFLD group (n = 25) based on the presence of fatty liver as determined by abdominal ultrasound. We demonstrated that the levels of serum SFAs, specifically palmitic acid and stearic acid, and the levels of n-6 PUFAs, specifically DGLA, and arachidonic acid (AA), were significantly higher in the NAFLD group. The serum palmitic acid, stearic acid, DGLA and AA levels were positively correlated with liver enzyme gamma-glutamyl transpeptidase (GGT). We further demonstrated by multivariate analysis that serum DGLA was a predictor of NAFLD. The serum DGLA level was negatively correlated with blood adiponectin and was positively correlated with blood leptin, high-sensitivity CRP, C-peptide index, and triglyceride-glucose index. Furthermore, delta-5-desaturase (D5D), the AA (product)/DGLA (precursor) ratio calculated from the product-to-precursor ratio of fatty acids, was significantly lower in the NAFLD group. These findings suggest that high serum DGLA levels in NAFLD group may be due to an excessive intake of n-6 PUFAs and changes in desaturase in the human body. High serum DGLA levels may also be associated with insulin resistance and inflammatory factors.

Assessment of the clinical value of five noninvasive predictors of metabolic dysfunction-associated steatotic liver disease in Han Chinese adults

BACKGROUND

Fatty Liver Index (FLI), Triglyceride-Glucose Index (TyG), Lipid Accumulation Product (LAP), Zhejiang University Index (ZJU), and Visceral Adiposity Index (VAI) are five classical predictive models for fatty liver disease. Our cross-sectional study aimed to identify the optimal predictors by comparing the predictive value of five models for metabolic dysfunction-associated steatotic liver disease (MASLD) risk.

METHODS

Data on 2687 participants were collected from West China Hospital of Sichuan University. Controlled attenuation parameters assessed by transient elastography were used to effectively diagnose MASLD. Logistic regression analysis was used to estimate the odd ratios and 95% confidence intervals between indices and MASLD risk. Receiver operating characteristic curves were plotted to evaluate the predictive value of indices.

RESULTS

This study included 1337 normal and 1350 MASLD samples. The average age of MASLD patients is 47 years old, and the prevalence was higher in males (39.3%) than in females (10.9%). Five indices were positively correlated with MASLD risk, with the strongest correlation for TyG. Overall, the area under the curve of the indicators was: ZJU 0.988, FLI 0.987, LAP 0.982, TyG 0.942, and VAI 0.941. In the gender stratification, ZJU (0.989) performed best in males. FLI (0.988) and ZJU (0.987) had similar predictive ability in females. In the age stratification, FLI performed better in predicting the middle-aged group aged 30-40 years (0.991).

CONCLUSION

For Chinese Han adults, ZJU is the best predictive index for initial screening of MASLD. FLI can serve as an alternative tool for ZJU to predict females.

Global Prevalence of Nonalcoholic Fatty Liver Disease: An Updated Review Meta-Analysis comprising a Population of 78 million from 38 Countries

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a global health challenge, with a rising rate in line with other metabolic diseases. We aimed to assess the global prevalence of NAFLD in adult and pediatric populations.

METHODS

PubMed, Scopus and Web of Science databases were systematically searched up to May 2023. Heterogeneity was assessed using Cochran's Q test and I2 statistics, and random-effects model was used for meta-analysis. Analyses were performed using STATA version 18.

RESULTS

A total of 479 studies with 78,001,755 participants from 38 countries were finally included. The global prevalence of NAFLD was estimated to be 30.2% (95% CI: 28.7-31.7%). Regionally, the prevalence of NAFLD was as follows: Asia 30.9% (95% CI: 29.2-32.6%), Australia 16.1% (95% CI: 9.0-24.8%), Europe 30.2% (95% CI: 25.6-35.0%), North America 29% (95% CI: 25.8-32.3%), and South America 34% (95% CI: 16.9-53.5%). Countries with a higher human development index (HDI) had significantly lower prevalence of NAFLD (coefficient = -0.523, p = 0.005). Globally, the prevalence of NAFLD in men and women was 36.6% (95% CI: 34.7-38.4%) and 25.5% (95% CI: 23.9-27.1%), respectively. The prevalence of NAFLD in adults, adults with obesity, children, and children with obesity was 30.2% (95% CI: 28.8-31.7%), 57.5% (95% CI: 43.6-70.9%), 14.3% (95% CI: 10.3-18.8%), and 38.0% (95% CI: 31.5-44.7%), respectively.

CONCLUSION

The prevalence of NAFLD is remarkably high, particularly in countries with lower HDI. This substantial prevalence in both adults and children underscores the need for disease management protocols to reduce the burden.

Usefulness of health checkup-based indices in identifying metabolic dysfunction-associated steatotic liver disease

Aims

The application of indices in the context of metabolic dysfunction-associated steatotic liver disease (MASLD) remains unexplored. We aimed to validate the ability of alanine aminotransferase (ALT), fatty liver index (FLI), and hepatic steatosis index (HSI) to identify MASLD during health checkups.

Methods

We recruited 627 participants and utilized their health checkup data and ultrasound to assess the potential of using ALT, FLI, and HSI as indices for MASLD; this was indicated by the area under the curve (AUC) and restricted cubic spline (RCS) model. The optimal, rule-out (sensitivity ≥90%), and rule-in (specificity ≥90%) cutoff values of each index for identifying MASLD were reported.

Results

Among participants with a median age of 46 years, the prevalence of MASLD was 28% in total (38% in males and 18% in females). RCS models confirmed a linear association between indices and MASLD. ROC analyses indicated that the AUC of ALT in identifying MASLD was 0.79 for the total cohort, 0.81 for males, and 0.69 for females. The optimal, rule-out, and rule-in cutoff values for ALT were 21, 13, and 29, respectively. Similarly, the AUC of FLI/HSI in identifying MASLD was 0.90/0.88 for the total cohort, 0.86/0.85 for males, and 0.93/0.90 for females. Considering the reference cutoff values, distinct cutoff values were observed between the sexes for FLI, while HSI had similar cutoff values.

Conclusion

This study demonstrated that ALT > 30 IU/L is a reasonable cutoff value to rule-in MASLD. ALT, FLI, and HSI are reliable indices for identifying MASLD during health checkups.

Fatty liver index (FLI): more than a marker of hepatic steatosis

Fatty liver index (FLI) was developed as a simple and accurate marker of hepatic steatosis. FLI is derived from an algorithm based on body mass index, waist circumference, and levels of triglycerides and gamma-glutamyltransferase, and it is widely used in clinical and epidemiological studies as a screening tool for discriminating between healthy and nonalcoholic fatty liver disease (NAFLD) subjects. However, a systematic review of the literature regarding FLI revealed that this index has more extensive relationships with biochemical and physiological parameters. FLI is associated with key parameters of lipid, protein and carbohydrate metabolism, hormones, vitamins and markers of inflammation, or oxidative stress. FLI can be a predictor or risk factor for a number of metabolic and nonmetabolic diseases and mortality. FLI is also used as an indicator for determining the effects of health-related prevention interventions, medications, and toxic substances on humans. Although in most cases, the exact mechanisms underlying these associations have not been fully elucidated, they are most often assumed to be mediated by insulin resistance, inflammation, and oxidative stress. Thus, FLI may be a promising marker of metabolic health due to its multiple associations with parameters of physiological and pathological processes. In this context, the present review summarizes the data from currently available literature on the associations between FLI and biochemical variables and physiological functions. We believe that this review will be of interest to researchers working in this area and can provide new perspectives and directions for future studies on FLI.

Validation of non-invasive indicators in the screening of metabolic dysfunction-associated fatty liver disease: a cross-sectional study among Uighurs in rural Xinjiang

BACKGROUND

Metabolic dysfunction-associated fatty liver disease (MAFLD) is the most common chronic liver disease in China. Our study aimed to evaluate the screening value of the fatty liver index (FLI), hepatic steatosis index (HSI), lipid accumulation product (LAP), visceral adiposity index (VAI), and Zhejiang University index (ZJU), as well as other single indicators for MAFLD. We aimed to find the optimal screening tool and its appropriate cut-off values for rural Uyghur adults.

METHODS

We completed a survey of 14,321 Uyghur adults in 51 groups in Kashgar, Xinjiang, in 2016 using a typical sampling method, with 12,794 patients ultimately included in statistical analyses. Fatty liver was diagnosed using ultrasonography.

RESULTS

The prevalence of fatty liver disease (FLD) and MAFLD was 16.73% and 16.55%, respectively, and the FLI, HSI, LAP, VAI, and ZJU were all independently associated with an increased risk of MAFLD. The areas under the receiver operating characteristic curves (AUCs) of the FLI for diagnosing MAFLD in men and women were 0.853 and 0.847, respectively. The AUCs of the body mass index (BMI) for diagnosing MAFLD in men and women were 0.850 and 0.852, respectively. Compared with other metabolic-related markers, FLI had the largest AUC. In men, the optimal cut-off values of FLI and BMI for diagnosing MAFLD were 45 (sensitivity 84.83%, specificity 69.57%) and 27.4 (sensitivity 78.47%, specificity 76.30%), respectively. In women, the optimal cut-off values of FLI and BMI for diagnosing MAFLD were 45 (sensitivity 80.11%, specificity 74.23%) and 28.0 (sensitivity 79.56%, specificity 75.41%), respectively. In men and women, an FLI score of < 30 ruled out MAFLD, while a score of ≥ 50 was a basis for diagnosis.

CONCLUSION

FLI and BMI had good screening ability for MAFLD and were superior to HSI, LAP, VAI, and ZJU in both sexes.

Utility of 99mTc-Sestamibi Heart/Liver Uptake Ratio in Screening Nonalcoholic Fatty Liver Disease During Myocardial Perfusion Imaging

Purpose: Nonalcoholic fatty liver disease (NAFLD) is the most common chronic hepatic disease worldwide, with functional impairment of the mitochondria occurring from early stages. Technetium-99m methoxy-isobutyl-isonitrile (99mTc-MIBI) is a lipophilic agent trapped in the mitochondria. This study aims to evaluate the utility of 99mTc-MIBI heart/liver uptake ratio in screening for NAFLD during myocardial perfusion imaging (MPI). Methods: Seventy eligible patients underwent a 2-d rest/stress 99mTc-MIBI scan with a 2-min planar image acquired in rest phase, at 30, 60, and 120 min postradiotracer administration. Heart/liver uptake ratio was calculated by placing identical regions of interest on the heart and liver dome. All patients underwent liver ultrasound and were allocated into groups A, having NAFLD; and B, healthy individuals without NAFLD. Results: Mean count per pixel heart/liver ratios gradually increased over time in either group; nonetheless the values were significantly higher in group A, regardless of acquisition timing; with the p-value equal to 0.007, 0.014, and 0.010 at 30, 60, and 120 min, respectively. Conclusion: Determining 99mTc-MIBI heart/liver uptake ratio during rest phase in patients undergoing MPI may be a useful, noninvasive screening method for NAFLD; with no additional cost, radiation burden, or adverse effects in these patients. Trial registration number: IR.SBMU.MSP.REC.1398.308.

Sex-specific relationship between non-alcoholic fatty liver disease and amyloid-β in cognitively unimpaired individuals

Background

Non-alcoholic fatty liver disease (NAFLD) is known to be associated with a high risk of clinically diagnosed Alzheimer's disease (AD). Additionally, the prevalence of NAFLD and AD is higher in elderly females than in males. However, a sex-specific association between NAFLD and amyloid-beta (Aβ) deposition remains unclear. Therefore, we investigated the sex-specific relationship between NAFLD and Aβ deposition in a large-sized cohort of cognitively unimpaired (CU) individuals.

Methods

We enrolled 673 (410 [60.9%] females and 263 [39.1%] males) CU individuals aged ≥45 years who underwent Aβ positron emission tomography (PET). The presence of NAFLD, assessed using the hepatic steatosis index, and the severity of NAFLD, assessed using the Fibrosis-4 index, were considered predictors. Aβ deposition on PET was considered as an outcome.

Results

Females had a higher frequency of NAFLD than males (48 and 23.2%, p < 0.001). Among females, the presence of NAFLD (β = 0.216, p < 0.001) was predictive of increased Aβ deposition, whereas among males, the presence of NAFLD (β = 0.191, p = 0.064) was not associated with Aβ deposition. Among females, the presence of NAFLD with low (β = 0.254, p = 0.039), intermediate (β = 0.201, p = 0.006), and high fibrosis (β = 0.257, p = 0.027) was predictive of increased Aβ deposition. Aβ deposition also increased as the severity of NAFLD increased in females (p for trend = 0.001).

Conclusion

We highlight the marked influence of NAFLD and its severity on the risk of Aβ deposition in relation to sex. Furthermore, our findings suggest that sex-specific strategies regarding the management of NAFLD are necessary for the prevention of Aβ deposition.

Validation of fatty liver index as a predictor of hepatic steatosis in Asian populations: Impact of alcohol consumption and sex

AIM

This study was undertaken to investigate the utility of the fatty liver index (FLI) as a noninvasive tool for predicting hepatic steatosis based on alcohol consumption and sex in a large Asian population.

METHODS

We carried out a single-center observational cohort study at the HITO Medical Center in Japan and enrolled 1976 Asian subjects. The subjects were categorized into nondrinkers and light drinkers (0-19 g/day) and moderate drinkers (20-59 g/day) based on their self-reported alcohol intake. We used physical examinations, laboratory tests, and a questionnaire to collect information on various factors related to the FLI, including body mass index, waist circumference, and levels of γ-glutamyl transferase and triglycerides.

RESULTS

The diagnostic accuracy of the FLI was assessed by calculating the area under the receiver operating characteristic curve (AUROC), and optimal cut-off values were determined using Youden's index. The FLI had an acceptable performance index of >0.7 both overall and in all subgroups, with an overall AUROC of 0.844. The AUROCs were higher in women and moderate drinkers of both sexes. We also compared the cut-off values obtained in the present study with the previously reported values of 30 and 60. Optimal cut-off values for the FLI were calculated for the total population and subgroups and were found to differ from the previously established values in other countries.

CONCLUSIONS

Our study suggests that the FLI is a useful noninvasive marker for predicting hepatic steatosis in a large Asian population, irrespective of alcohol consumption and sex.

Liver fat as risk factor of hepatic and cardiometabolic diseases

Non-alcoholic fatty liver disease (NAFLD) is a disorder characterized by excessive accumulation of fat in the liver that can progress to liver inflammation (non-alcoholic steatohepatitis [NASH]), liver fibrosis, and cirrhosis. Although most efforts for drug development are focusing on the treatment of the latest stages of NAFLD, where significant fibrosis and NASH are present, findings from studies suggest that the amount of liver fat may be an important independent risk factor and/or predictor of development and progression of NAFLD and metabolic diseases. In this review, we first describe the current tools available for quantification of liver fat in humans and then present the clinical and pathophysiological evidence that link liver fat with NAFLD progression as well as with cardiometabolic diseases. Finally, we discuss current pharmacological and non-pharmacological approaches to reduce liver fat and present open questions that have to be addressed in future studies.

Comparison of the diagnostic performance of twelve noninvasive scores of metabolic dysfunction-associated fatty liver disease

BACKGROUND

The absence of distinct symptoms in the majority of individuals with metabolic dysfunction-associated fatty liver disease (MAFLD) poses challenges in identifying those at high risk, so we need simple, efficient and cost-effective noninvasive scores to aid healthcare professionals in patient identification. While most noninvasive scores were developed for the diagnosis of nonalcoholic fatty liver disease (NAFLD), consequently, the objective of this study was to systematically assess the diagnostic ability of 12 noninvasive scores (METS-IR/TyG/TyG-WC/TyG-BMI/TyG-WtHR/VAI/HSI/FLI/ZJU/FSI/K-NAFLD) for MAFLD.

METHODS

The study recruited eligible participants from two sources: the National Health and Nutrition Examination Survey (NHANES) 2017-2020.3 cycle and the database of the West China Hospital Health Management Center. The performance of the model was assessed using various metrics, including area under the receiver operating characteristic curve (AUC), net reclassification index (NRI), integrated discrimination improvement (IDI), decision curve analysis (DCA), and subgroup analysis.

RESULTS

A total of 7398 participants from the NHANES cohort and 4880 patients from the Western China cohort were included. TyG-WC had the best predictive power for MAFLD risk in the NHANES cohort (AUC 0.863, 95% CI 0.855-0.871), while TyG-BMI had the best predictive ability in the Western China cohort (AUC 0.903, 95% CI 0.895-0.911), outperforming other models, and in terms of IDI, NRI, DCA, and subgroup analysis combined, TyG-WC remained superior in the NAHANES cohort and TyG-BMI in the Western China cohort.

CONCLUSIONS

TyG-BMI demonstrated satisfactory diagnostic efficacy in identifying individuals at a heightened risk of MAFLD in Western China. Conversely, TyG-WC exhibited the best diagnostic performance for MAFLD risk recognition in the United States population. These findings suggest the necessity of selecting the most suitable predictive models based on regional and ethnic variations.

Utility of Indices Obtained during Medical Checkups for Predicting Fatty Liver Disease in Non-obese People

Objective To predict fatty liver disease (FLD), including nonalcoholic FLD (NAFLD) and metabolic dysfunction-associated FLD (MAFLD), from blood tests and anthropometric measurements, the fatty liver index (FLI) and triglyceride glucose-body mass index (TyG-BMI) have been reported as promising indicators. We evaluated the predictive ability of several indices, including the waist circumference, BMI, FLI and TyG-BMI, that might predict FLD in non-obese individuals undergoing health checkups. Methods This retrospective observational study enrolled non-obese subjects who underwent abdominal ultrasonography between May 1, 2015, and June 30, 2022. Obesity was defined as a BMI <25 kg/m2. FLD was diagnosed by abdominal ultrasonography. Using a receiver operating characteristic analysis, we examined the predictive validity of indices for NAFLD and MAFLD by calculating the area under the curve (AUC). Results Of the 24,825 subjects (mean age 44.3±10.0 years old; 54% men) enrolled in this examination of the association of indices, including FLI and TyG-BMI, with NAFLD, NAFLD was diagnosed in 3,619 (27%) men and 733 (6%) women. In both men and women, the FLI and TyG-BMI had significantly higher AUC values for NAFLD prediction than the other indicators (FLI: 0.786 for men and 0.875 for women, TyG-BMI: 0.783 for men and 0.868 for women). In analyses of subjects with a BMI <23 kg/m2, the superiority of the FLI and TyG-BMI remained unchanged. The FLI and TyG-BMI also had significantly higher AUC values for MAFLD prediction than the other indicators. Conclusion The FLI and TyG-BMI had a particularly high predictive ability for NAFLD and MAFLD in non-obese subjects.

Assessing the clinical utility of major indices for nonalcoholic fatty liver disease in East Asian populations

Nonalcoholic fatty liver disease (NAFLD) is currently the most common form of chronic liver disease. The growing prevalence of NAFLD is strongly associated with the high incidence of metabolic syndrome. NAFLD affects as much as 19% of the US population with a disproportionate impact on minority racial groups such as Asian Americans. If not promptly managed, NAFLD may progress to more feared complications. Liver indices for NAFLD screening have been proposed but were often developed using study populations with different anthropometrics than patients of East Asian descent. This review compares the accuracy of five indices for NAFLD screening in Asian cohorts. The Fatty Liver Index performed well in multiple large-scale community studies, although other indices may be more suited for specific patient cohorts. This is important, as the utilization of liver indices could accelerate screening for NAFLD for early management and to reduce liver disease-related health disparities among Asian Americans.

CT-based Hounsfield unit values reflect the degree of steatohepatitis in patients with low-grade fatty liver disease

BACKGROUND/AIMS

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide. Ultrasound, the most used tool for diagnosing NAFLD, is operator-dependent and shows suboptimal performance in patients with mild steatosis. However, few studies have been conducted on whether alternative noninvasive methods are useful for diagnosing mild hepatic steatosis. Also, little is known about whether noninvasive tests are useful for grading the severity of hepatic steatosis or the degree of intrahepatic inflammation. Therefore, we aimed to evaluate whether the HSI, the FLI and HU values in CT could be used to discriminate mild hepatic steatosis and to evaluate the severity of hepatic steatosis or the degree of intrahepatic inflammation in patients with low-grade fatty liver disease using liver biopsy as a reference standard.

METHODS

Demographic, laboratory, CT imaging, and histological data of patients who underwent liver resection or biopsy were analyzed. The performance of the HSI, HU values and the FLI for diagnosing mild hepatic steatosis was evaluated by calculating the area under the receiver operating characteristic curve. Whether the degree of hepatic steatosis and intrahepatic inflammation could be predicted using the HSI, HU values or the FLI was also analyzed. Moreover, we validate the results using magnetic resonance imaging proton density fat fraction as an another reference standard.

RESULTS

The AUROC for diagnosing mild hepatic steatosis was 0.810 (p < 0.001) for the HSI, 0.732 (p < 0.001) for liver HU value, 0.802 (p < 0.001) for the difference between liver and spleen HU value (L-S HU value) and 0.813 (p < 0.001) for the FLI. Liver HU and L-S HU values were negatively correlated with the percentage of hepatic steatosis and NAFLD activity score (NAS) and significantly different between steatosis grades and between NAS grades. The L-S HU value was demonstrated the good performance for grading the severity of hepatic steatosis and the degree of intrahepatic inflammation.

CONCLUSIONS

The HU values on CT are feasible for stratifying hepatic fat content and evaluating the degree of intrahepatic inflammation, and the HSI and the FLI demonstrated good performance with high sensitivity and specificity in diagnosing mild hepatic steatosis.

Diagnostic ability using fatty liver and metabolic markers for metabolic-associated fatty liver disease stratified by metabolic/glycemic abnormalities

AIMS/INTRODUCTION

Although several noninvasive predictive markers for fatty liver and metabolic markers have been used for fatty liver prediction, whether such markers can also predict metabolic-associated fatty liver disease (MAFLD) remains unclear. We aimed to examine the ability of existing fatty liver or metabolic markers to predict MAFLD.

MATERIALS AND METHODS

Participants in a high-volume center in Tokyo were classified into groups with and without MAFLD, based on the presence of metabolic abnormalities and fatty liver diagnosed through abdominal ultrasonography, between 2008 and 2018. The diagnostic abilities of three fatty liver markers: fatty liver index (FLI), hepatic steatosis index (HSI), and lipid accumulation product (LAP), and three common metabolic markers: waist-to-height ratio (WHR), body mass index (BMI), and waist circumference (WC), for predicting MAFLD, were evaluated. Analyses stratified by MAFLD subtypes were performed.

RESULTS

Of 92,374 individuals, 19,392 (36.1%) had MAFLD. The diagnostic performances for MAFLD prediction, measured as c-statistics, for FLI, HSI, LAP, WHR, BMI, and WC were 0.906, 0.892, 0.878, 0.844, 0.877, and 0.878, respectively. Optimal cutoff values for diagnosing MAFLD for FLI, HSI, LAP, WHR, BMI, and WC were 20.3, 32.7, 20.0, 0.49, 22.9, and 82.1, respectively. Analyses stratified by MAFLD subtypes, based on BMI and metabolic/glycemic abnormalities, suggested that FLI and HSI had acceptable (c-statistics >0.700) diagnostic abilities throughout all the analyses.

CONCLUSIONS

All six markers were excellent predictors of MAFLD in diagnosing among the general population, with FLI and HSI particularly useful among all sub-populations.

Irisin Is Related to Non-Alcoholic Fatty Liver Disease (NAFLD)

Irisin is a cytokine involved in many metabolic pathways occurring, among others, in muscles, adipose tissue and liver. Thus, fluctuations in irisin levels are suggested to be related to metabolic diseases. Therefore, the purpose of our study was to evaluate whether irisin may be associated with non-alcoholic fatty liver disease (NAFLD). A total of 138 patients (70/68 male/female, mean age 65.61 ± 10.44 years) were enrolled in the study. The patients were assigned to the NAFLD group (n = 72, including 46 patients with type 2 diabetes (T2DM]) and the group without NAFLD (n = 66, 31 patients with T2DM). NAFLD was diagnosed based on ultrasound examination, Hepatic Steatosis Index (HSI) and Fatty Liver Index. Baseline anthropometric, blood pressure and biochemical parameters were collected. The serum irisin level was determined using an ELISA test. We observed that NAFLD was associated with an increased concentration of irisin. Moreover, Spearman correlations and linear regression analysis revealed that irisin level correlates with some anthropometric and biochemical parameters such as body mass index, glycated hemoglobin, aspartic aminotransferase, creatinine and urea. Logistic regression analysis depicted that odds for NAFLD increase 1.17 times for each 1 μg/mL rise of irisin concentration. Finally, ROC analysis showed that the concentration of irisin possesses a discriminate capacity for NAFLD and optimal cut points concentration could be designed. The risk of NAFLD in the subgroup with irisin concentration above 3.235 μg/mL was 4.57 times higher than in patients with the lower concentration of irisin. To conclude, the obtained results suggest that irisin concentration is associated with some anthropometric and biochemical parameters and should be further investigated toward its usage as a diagnostic biomarker of NAFLD.

Comparison of the Diagnostic Performance of Steatosis Indices for Discrimination of CT-Diagnosed Metabolic Dysfunction-Associated Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) was redefined as metabolic dysfunction-associated fatty liver disease (MAFLD) in 2020. Due to this, further validation of the non-invasive tests used in NAFLD diagnosis is required for MAFLD. There are five known steatosis indices for computed tomography (CT)-diagnosed MAFLD. These indices include the fatty liver index (FLI), the hepatic steatosis index (HSI), the lipid accumulation product (LAP), the visceral adiposity index (VAI), and the Zhejiang University index (ZJU). We aimed to analyze the diagnostic abilities of these five widely known steatosis indices for CT-diagnosed MAFLD. From March 2012 to October 2019, we retrospectively analyzed the clinical information and images of 1300 adults aged ≥19 years who underwent CT scans at our institution. To compare differences, the Chi-square test and independent t-test were used for categorical and continuous variables, respectively. The area under the receiver operating characteristic (AUROC) curve was used to validate the diagnostic accuracy of MAFLD. Of the five indices, FLI was the best at predicting MAFLD, with the highest AUROC (0.791). The sensitivity and specificity of FLI for diagnosing MAFLD were both 70.9%. The optimal cut-off value was 29.9. FLI is a useful surrogate index for screening MAFLD in clinical practice.

Prediction and validation of nonalcoholic fatty liver disease by fatty liver index in a Japanese population

Fatty liver index (FLI) calculated by using body mass index (BMI), waist circumference and levels of γ-glutamyl transferase and triglycerides is a non-invasive predictor of nonalcoholic fatty liver disease (NAFLD). The original study in Italy showed that the cutoff level for prediction of NAFLD was FLI ≥60. However, the sex difference in FLI was not taken into consideration, and it is unclear whether the cutoff value can be applied to other races. We investigated the cutoff value of FLI for prediction of NAFLD determined by abdominal ultrasonography using receiver operating characteristic curve analyses in 14,471 Japanese subjects (men/women: 9,240/5,231; mean age: 48 ± 9 years). There was a significant interaction between sex and FLI for detection of NAFLD (p < 0.001). The cutoff values of FLI in men and women were 35.1 (area under the curve [AUC]: 0.82) and 15.6 (AUC: 0.91), respectively. When the subjects were divided by the absence and presence of obesity (BMI ≥25), there was a significant interaction between FLI and obesity for detection of NAFLD in women (p < 0.001) but not in men (p = 0.679). The cutoff values of FLI in non-obese/obese men and women were 22.6/52.6 and 11.2/33.2, respectively. In conclusion, the cutoff value of FLI for prediction of NAFLD in Japanese individuals was lower than that in the original study, and there is a significant sex difference. The simple and useful cutoff values in Japanese men and women are FLI ≥35 (non-obese/obese: 23/53) and FLI ≥16 (non-obese/obese: 11/33), respectively.

Relationship between the dynamics of non-alcoholic fatty liver disease and incident diabetes mellitus

The aim of the current study was to evaluate the association between changes in non-alcoholic fatty liver disease (NAFLD) over time and risk of incident diabetes mellitus (DM). In total, 3047 subjects without underlying DM were followed up for 14 years from the Anseong-Ansan cohort. NAFLD status was determined biennially using the hepatic steatosis index (HSI), and subjects were clustered into seven groups according to changes in HSI, body mass index (BMI), and homeostatic model assessment of insulin resistance (HOMA-IR): none, persistent, transient, transient resolved, resolved, incident, and recurrent NAFLD (Groups 1-7, respectively). Predictive abilities were compared between the dynamics of HSI and single time points. Regarding the changes in HSI, the risk of incident DM was highest in Group 2 (hazard ratio [HR] 2.710; P < 0.001), followed by Groups 7 (HR 2.062; P < 0.001) and 3 (HR 1.559; P = 0.027). The predictive ability for DM was powerful in order of HOMA-IR, HSI and BMI. The dynamics of NAFLD were less predictive of incident DM than single time-point NAFLD. In conclusion, NAFLD is more useful than BMI in predicting incident DM. However, NAFLD status at single time points can better predict incident DM than dynamic changes in HSI.

Comparison of hepatic steatosis index as noninvasive diagnostic tool and liver ultrasound for non-alcoholic steatosis in the adult population

Aim

This study aimed to evaluate hepatic steatosis index (HSI) as a non-invasive tool in diagnosing and predicting nonalcoholic fatty liver disease (NAFLD) and to compare it with abdominal ultrasound as the gold standard tool.

Background

NAFLD is a general term attributed to the deposition of adipose tissue in the liver leading to hepatitis, fibrosis, cirrhosis, and also hepatocellular carcinoma (HCC). Rapid and valid screening can remarkably prevent the progression of this disease.

Methods

A total of 464 people were included in the present study based on inclusion criteria. Patients were evaluated for body mass index (BMI), AST, ALT, and ALP indices. The liver echogenicity of patients was evaluated by abdominal ultrasound technique.

Results

The results showed that out of 464 people included in the study, 32.33% represented fatty liver. It was found that 79.1% of patients were female. There was no significant difference between the two groups in terms of age. Furthermore, it was found that ALT, AST, and ALP levels were significantly increased in the two groups of patients compared to the control group. It was determined that out of 150 patients, 75.3% were grade I and 24.7% were grade II NAFLD cases; no grade III cases were observed. The mean HSI for the NAFLD- group was 35.51±5.72 and for the NAFLD+ group was 42.84±5.70, a significant difference. The receiver operating characteristic (ROC) curve also showed that the area under the curve (AUC) of HSI was 0.833 (95% CI, 0.796-0.870) for detecting NAFLD patients. At the cutoff point of > 36.0, the sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) were 88.7% (95% CI, 82.5-92.5), 63.4% (95% CI, 57.9-68.5), 92.1%, and 53.6%, respectively. Pearson correlation showed a direct and significant correlation between ultrasound data and HSI values.

Conclusion

Overall, the present study results showed that HSI as a non-invasive and non-imaging tool can diagnose NAFLD.

The Association Between Coffee Consumption and Nonalcoholic Fatty Liver Disease in the South Korean General Population

SCOPE

To identify the cross-sectional and prospective association between coffee consumption and nonalcoholic fatty liver disease (NAFLD) among South Korean adults.

METHODS AND RESULTS

Participants are selected from the Health Examinees study. NAFLD is defined using three non-invasive indexes: fatty liver index (FLI), hepatic steatosis index, and fibrosis-4 calculator (FIB-4). In the cross-sectional analysis, higher habitual coffee consumption is associated with a lower risk for NAFLD, define using the FLI, (men, odds ratio [OR] 0.702; women, OR 0.810) compared with non-consumers. Participants who consumed coffee with sugar and creamer also have a lower risk for NAFLD, defined using the FIB-4, compared with non-coffee-consumers (men, OR 0.739; women, OR 0.807). A prospective analysis indicated that higher coffee consumption is associated with a lower incidence of NAFLD, defined using the FLI, in men (hazard ratio, 0.706). In both men and women, a lower FIB-4 index score is associated with higher coffee consumption regardless of coffee type (all p-value <0.05).

CONCLUSIONS

 Coffee consumption of >3 cups per day has a protective effect against the development of NAFLD to a certain extent, and a negative association is found between coffee consumed with sugar and creamer and the FIB-4 index score in South Korean adults.

Three Different Genetic Risk Scores Based on Fatty Liver Index, Magnetic Resonance Imaging and Lipidomic for a Nutrigenetic Personalized Management of NAFLD: The Fatty Liver in Obesity Study

Non-alcoholic fatty liver disease (NAFLD) affects 25% of the global population. The pathogenesis of NAFLD is complex; available data reveal that genetics and ascribed interactions with environmental factors may play an important role in the development of this morbid condition. The purpose of this investigation was to assess genetic and non-genetic determinants putatively involved in the onset and progression of NAFLD after a 6-month weight loss nutritional treatment. A group of 86 overweight/obese subjects with NAFLD from the Fatty Liver in Obesity (FLiO) study were enrolled and metabolically evaluated at baseline and after 6 months. A pre-designed panel of 95 genetic variants related to obesity and weight loss was applied and analyzed. Three genetic risk scores (GRS) concerning the improvement on hepatic health evaluated by minimally invasive methods such as the fatty liver index (FLI) (GRSFLI), lipidomic-OWLiver®-test (GRSOWL) and magnetic resonance imaging (MRI) (GRSMRI), were derived by adding the risk alleles genotypes. Body composition, liver injury-related markers and dietary intake were also monitored. Overall, 23 SNPs were independently associated with the change in FLI, 16 SNPs with OWLiver®-test and 8 SNPs with MRI, which were specific for every diagnosis tool. After adjusting for gender, age and other related predictors (insulin resistance, inflammatory biomarkers and dietary intake at baseline) the calculated GRSFLI, GRSOWL and GRSMRI were major contributors of the improvement in hepatic status. Thus, fitted linear regression models showed a variance of 53% (adj. R2 = 0.53) in hepatic functionality (FLI), 16% (adj. R2 = 0.16) in lipidomic metabolism (OWLiver®-test) and 34% (adj. R2 = 0.34) in liver fat content (MRI). These results demonstrate that three different genetic scores can be useful for the personalized management of NAFLD, whose treatment must rely on specific dietary recommendations guided by the measurement of specific genetic biomarkers.

Performance of Fatty Liver Index in Identifying Non-Alcoholic Fatty Liver Disease in Population Studies. A Meta-Analysis

Background. Fatty liver index (FLI) is a non-invasive tool used to stratify the risk of non-alcoholic fatty liver disease (NAFLD) in population studies; whether it can be used to exclude or diagnose this disorder is unclear. We conducted a meta-analysis to assess the prevalence of NAFLD in each FLI class and the performance of FLI in detecting NAFLD. Methods. Four databases were searched until January 2021 (CRD42021231367). Original articles included were those reporting the performance of FLI and adopting ultrasound, computed tomography, or magnetic resonance as a reference standard. The numbers of subjects with NAFLD in FLI classes <30, 30–60, and ≥60, and the numbers of subjects classified as true/false positive/negative when adopting 30 and 60 as cut-offs were extracted. A random-effects model was used for pooling data. Results. Ten studies were included, evaluating 27,221 subjects without secondary causes of fatty liver disease. The prevalence of NAFLD in the three FLI classes was 14%, 42%, and 67%. Sensitivity, specificity, positive predictive value, negative predictive value, likelihood ratio for positive results, likelihood ratio for negative results, and diagnostic odds ratio were 81%, 65%, 53%, 84%, 2.3, 0.3, and 7.8 for the lower cut-off and 44%, 90%, 67%, 76%, 4.3, 0.6, and 7.3 for the higher cut-off, respectively. A similar performance was generally found in studies adopting ultrasound versus other imaging modalities. Conclusions. FLI showed an adequate performance in stratifying the risk of NAFLD. However, it showed only weak evidence of a discriminatory performance in excluding or diagnosing this disorder.