Validation of conventional non-invasive fibrosis scoring systems in patients with metabolic associated fatty liver disease

Clinical characteristics of lean and non-lean non-alcoholic fatty liver disease: a cross-sectional study

INTRODUCTION

Non-alcoholic fatty liver disease (NAFLD) affects more than a quarter of the global population and has become the world's number one chronic liver disease, seriously jeopardizing public life and health. Despite the new terminology of metabolic dysfunction-associated steatotic liver disease (MASLD) has been proposed, the mechanisms underlying the heterogeneity across BMI stratification in non-alcoholic fatty liver disease (NAFLD) remain unclear. The aim of this study was to reveal the differences in metabolic and fibrotic characteristics between lean (BMI < 23 kg/m2) and non-lean NAFLD in an Asian population.

METHODS

The current study collected NAFLD patients from the physical examination population. Patients were divided into two groups by BMI to compare their clinical parameters, including lean (BMI < 23 kg/m2) and non-lean (BMI ≥ 23 kg/m2) and fibrosis subgroups (with a threshold of LSM = 8 kPa) and analyzed for risk factors by logistic regression models.

RESULTS

Of the 11,577 NAFLD patients who participated in the study, there were 916 lean and 10,661 non-lean. The non-lean group was younger than the lean group (median age 50 vs. 52 years, P < 0.001) and had a significantly higher prevalence of hypertension (28.0% vs. 18.3%), diabetes mellitus (10.1% vs. 6.1%), and liver fibrosis (9.1% vs. 5.1%) (all P < 0.001). Analysis of metabolic indexes showed that TyG, TyG-BMI, TG/HDL-C and APRI were higher in the non-lean group (all P < 0.001). Gender stratification revealed that ALT was significantly higher in the male non-lean group, while HDL-C was lower in the female non-lean group (1.35 vs. 1.47 mmol/L). Multiple regression suggested that the risk of fibrosis was independently associated with CAP values and fasting glucose, BMI, direct bilirubin, globulin, and age in the non-lean group, whereas the risk was mainly driven by GGT and ALP in the lean group.

CONCLUSIONS

Non-lean NAFLD patients showed more significant metabolic disturbances and risk of liver fibrosis. Although metabolic indicators (TyG, FIB-4) have limited predictive value for liver fibrosis, they are strongly associated with metabolic risk in MASLD.

Diagnostic accuracy of FibroScan-AST (FAST) score, non-alcoholic fatty liver fibrosis score (NFS), FibroScan, and liver fibrosis index (FIB-4) for identifying fibrotic non-alcoholic steatohepatitis in patients with chronic hepatitis B with metabolic dysfunction-associated fatty liver disease

OBJECTIVE

To evaluate the diagnostic value of the FibroScan-AST (FAST) score, non-alcoholic fatty liver fibrosis score (NFS), FibroScan, and liver fibrosis index (FIB-4) for identifying fibrotic non-alcoholic steatohepatitis (NASH) in patients with chronic hepatitis B (CHB) with metabolic dysfunction-associated fatty liver disease (MAFLD).

METHODS

All patients with CHB and MAFLD who underwent liver biopsy at the Zhenjiang Third Hospital affiliated with Jiangsu University between August 2010 and December 2022 were included in the analysis. The diagnostic accuracy of FAST, NFS, FibroScan, and FIB-4 for diagnosing NASH and liver fibrosis were evaluated based on the area under the receiver-operating characteristic curve (AUC).

RESULTS

A total of 156 patients with CHB combined with MAFLD were included, including 69 with NASH and fibrosis stage 2 or higher (NASH+F ≥ 2), and 16 with NASH and cirrhosis (NASH+F4). The AUC of FAST, NFS, liver stiffness measurement (LSM), and FIB-4 for diagnosing NASH+F ≥ 2 was 0.739 (p < 0.001), 0.643 (p = 0.006), 0.754 (p < 0.001), and 0.665 (p = 0.003), respectively. The specificity of FAST, NFS, LSM, and FIB-4 was 67%, 51.8%, 78.6% and 76.8%, respectively, and the sensitivity was 75%, 78.6%, 67.9%, and 53.6%, respectively. No significant differences were found between groups. The AUC of FAST, NFS, LSM, and FIB-4 for diagnosing NASH+F4 was 0.650 (p = 0.038), 0.725 (p = 0.001), 0.851 (p < 0.001), and 0.560 (p = 0.533), respectively. The specificity of the FAST, NFS, LSM, and FIB-4 was 55.9%, 50.0%, 71.6%, and 75.5%, respectively and the sensitivity was 80.0%, 100%, 100%, and 50.0%, respectively. The differences between AUCs of FIB-4 and FAST compared with LSM were 0.291 and 0.201, respectively (p < 0.05).

CONCLUSION

In patients with CHB combined with MAFLD, FAST did not have better accuracy than NFS and FIB-4 for predicting fibrotic NASH, whereas LSM had better accuracy than FAST and FIB-4.

Metabolic (dysfunction)-associated fatty liver disease metrics and contributions to liver research

BACKGROUND

The international consensus to revise non-alcoholic fatty liver disease to metabolic (dysfunction)-associated fatty liver disease (MAFLD) in 2020 attracted significant attention. The impact of the MAFLD definition on the research community has not been objectively assessed. We conducted an analysis of systematically collected literature on MAFLD to understand its research impact.

METHODS

From PubMed, Web of Science, and Scopus, the literature adopting MAFLD, written in English, and published from 2020 to 10 October 2023 was collected. The publication metrics, including publication counts, publishing journals, author countries, author keywords, and citation information, were analyzed to evaluate the research impact and key topics on MAFLD.

RESULTS

1469 MAFLD-related papers were published in 434 journals with a steady increase in the number. The intense publishing and citations activity on MAFLD indicates the large impact of the redefinition. Topic assessment with keyword and citation analysis revealed a transition from the proposal and discussion of the redefinition to clinical characterization of MAFLD with a focus on metabolic dysfunction. Moreover, the diagnostic criteria for MAFLD showed better performance in predicting hepatic and extrahepatic outcomes compared to NAFLD. The publications were from 99 countries with evidence of strong regional and global collaboration. Multiple international societies and stakeholders have endorsed MAFLD for its utility in clinical practice, improving patient management and promoting multidisciplinary care, while alleviating stigma.

CONCLUSION

This survey provides a quantitative measure of the considerable international impact and contributions of the MAFLD definition towards liver research and as part of the spectrum of cardiometabolic disorders.

Non-invasive Scores and Serum Biomarkers for Fatty Liver in the Era of Metabolic Dysfunction-associated Steatotic Liver Disease (MASLD): A Comprehensive Review From NAFLD to MAFLD and MASLD

PURPOSE OF REVIEW

The prevalence of non-alcoholic fatty liver disease (NAFLD) is rapidly increasing worldwide, making it the leading cause of liver related morbidity and mortality. Currently, liver biopsy is the gold standard for assessing individuals with steatohepatitis and fibrosis. However, its invasiveness, sampling variability, and impracticality for large-scale screening has driven the search for non-invasive methods for early diagnosis and staging. In this review, we comprehensively summarise the evidence on the diagnostic performance and limitations of existing non-invasive serum biomarkers and scores in the diagnosis and evaluation of steatosis, steatohepatitis, and fibrosis.

RECENT FINDINGS

Several non-invasive serum biomarkers and scores have been developed over the last decade, although none has successfully been able to replace liver biopsy. The introduction of new NAFLD terminology, namely metabolic dysfunction-associated fatty liver disease (MAFLD) and more recently metabolic dysfunction-associated steatotic liver disease (MASLD), has initiated a debate on the interchangeability of these terminologies. Indeed, there is a need for more research on the variability of the performance of non-invasive serum biomarkers and scores across the diagnostic entities of NAFLD, MAFLD and MASLD. There remains a significant need for finding valid and reliable non-invasive methods for early diagnosis and assessment of steatohepatitis and fibrosis to facilitate prompt risk stratification and management to prevent disease progression and complications. Further exploration of the landscape of MASLD under the newly defined disease subtypes is warranted, with the need for more robust evidence to support the use of commonly used serum scores against the new MASLD criteria and validation of previously developed scores.

Establishment and Evaluation of a Noninvasive Metabolism-Related Fatty Liver Screening and Dynamic Monitoring Model: Cross-Sectional Study

BACKGROUND

Metabolically associated fatty liver disease (MAFLD) insidiously affects people's health, and many models have been proposed for the evaluation of liver fibrosis. However, there is still a lack of noninvasive and sensitive models to screen MAFLD in high-risk populations.

OBJECTIVE

The purpose of this study was to explore a new method for early screening of the public and establish a home-based tool for regular self-assessment and monitoring of MAFLD.

METHODS

In this cross-sectional study, there were 1758 eligible participants in the training set and 200 eligible participants in the testing set. Routine blood, blood biochemistry, and FibroScan tests were performed, and body composition was analyzed using a body composition instrument. Additionally, we recorded multiple factors including disease-related risk factors, the Forns index score, the hepatic steatosis index (HSI), the triglyceride glucose index, total body water (TBW), body fat mass (BFM), visceral fat area, waist-height ratio (WHtR), and basal metabolic rate. Binary logistic regression analysis was performed to explore the potential anthropometric indicators that have a predictive ability to screen for MAFLD. A new model, named the MAFLD Screening Index (MFSI), was established using binary logistic regression analysis, and BFM, WHtR, and TBW were included. A simple rating table, named the MAFLD Rating Table (MRT), was also established using these indicators.

RESULTS

The performance of the HSI (area under the curve [AUC]=0.873, specificity=76.8%, sensitivity=81.4%), WHtR (AUC=0.866, specificity=79.8%, sensitivity=80.8%), and BFM (AUC=0.842, specificity=76.9%, sensitivity=76.2%) in discriminating between the MAFLD group and non-fatty liver group was evaluated (P<.001). The AUC of the combined model including WHtR, HSI, and BFM values was 0.900 (specificity=81.8%, sensitivity=85.6%; P<.001). The MFSI was established based on better performance at screening MAFLD patients in the training set (AUC=0.896, specificity=83.8%, sensitivity=82.1%) and was confirmed in the testing set (AUC=0.917, specificity=89.8%, sensitivity=84.4%; P<.001).

CONCLUSIONS

The novel MFSI model was built using WHtR, BFM, and TBW to screen for early MAFLD. These body parameters can be easily obtained using a body fat scale at home, and the mobile device software can record specific values and perform calculations. MFSI had better performance than other models for early MAFLD screening. The new model showed strong power and stability and shows promise in the area of MAFLD detection and self-assessment. The MRT was a practical tool to assess disease alterations in real time.

Metabolic dysfunction-associated steatotic liver disease: Evolution of the final terminology

The medical term nonalcoholic fatty liver disease (NAFLD) was coined in 1986 for a condition that has since become the most prevalent liver disorder worldwide. In the last 3 years, the global professional community launched 2 consecutive efforts to purge NAFLD from the medical dictionary and recommended new terms based on disease pathophysiology rather than distinction from similar conditions featuring liver steatosis. A consensus by renowned clinical scholars primarily residing in the Asian-Pacific region introduced metabolic dysfunction-associated fatty liver disease (MAFLD) as a new name to replace NAFLD in 2020. In 2023, a nomenclature and classification resulting in the term metabolic dysfunction-associated steatotic liver disease (MASLD) was developed by a large expert panel under the auspices of leading liver societies from Europe and Americas. These marked and rapid shifts in nomenclature have garnered the attention of many researchers and clinicians across the globe due to the multilevel impact of a frequent and potentially progressive chronic liver disease in both adult and pediatric populations. The proposed terminologies differ in several ways but they have more in common than differences. They both capture key features of liver disease associated with cardiometabolic risk factors and with significant impact on all-cause and liver-related mortality. The framework of MASLD has incorporated many innovative aspects of MAFLD and while several conceptual disparities remain a work in progress, global efforts should focus on new insights into disease pathogenesis, outcome trajectories, prevention, and treatment. Here, some of these challenges are discussed to facilitate this process.

Development of a novel non-invasive biomarker panel for hepatic fibrosis in MASLD

Accurate non-invasive biomarkers to diagnose metabolic dysfunction-associated steatotic liver disease (MASLD)-related fibrosis are urgently needed. This study applies a translational approach to develop a blood-based biomarker panel for fibrosis detection in MASLD. A molecular gene expression signature identified from a diet-induced MASLD mouse model (LDLr-/-.Leiden) is translated into human blood-based biomarkers based on liver biopsy transcriptomic profiles and protein levels in MASLD patient serum samples. The resulting biomarker panel consists of IGFBP7, SSc5D and Sema4D. LightGBM modeling using this panel demonstrates high accuracy in predicting MASLD fibrosis stage (F0/F1: AUC = 0.82; F2: AUC = 0.89; F3/F4: AUC = 0.87), which is replicated in an independent validation cohort. The overall accuracy of the model outperforms predictions by the existing markers Fib-4, APRI and FibroScan. In conclusion, here we show a disease mechanism-related blood-based biomarker panel with three biomarkers which is able to identify MASLD patients with mild or advanced hepatic fibrosis with high accuracy.

Metabolic puzzle: Exploring liver fibrosis differences in Asian metabolic-associated fatty liver disease subtypes

BACKGROUND

Metabolic-associated fatty liver disease (MAFLD) is a liver condition marked by excessive fat buildup in the absence of heavy alcohol use. It is primarily linked with metabolic issues like insulin resistance, obesity, and abnormal lipid levels, and is often observed with other conditions such as type 2 diabetes and cardiovascular disease. However, whether the subtypes of MAFLD based on the metabolic disorder differentially impact liver fibrosis is not well explicated, especially in the Asian population.

AIM

To compare the severity of liver fibrosis among different MAFLD subtypes.

METHODS

A total of 322 adult patients of either gender with fatty liver on ultrasound were enrolled between January to December 2021. MAFLD was defined as per the Asian Pacific Association for the Study of the Liver guidelines. Fibrosis-4 index (Fib-4) and nonalcoholic fatty liver disease fibrosis score (NFS) were employed to evaluate liver fibrosis.

RESULTS

The mean age was 44.84 ± 11 years. Seventy-two percent of the patients were female. Two hundred and seventy-three patients were classified as having MAFLD, of which 110 (40.3%) carried a single, 129 (47.3%) had two, and 34 (12.5%) had all three metabolic conditions. The cumulative number of metabolic conditions was related to elevated body mass index, triglyceride (TG) levels, and glycated hemoglobin, lower high-density lipoprotein (HDL) levels, higher liver inflammation (by aspartate aminotransferase and γ-glutamyl transferase), and higher likelihood of fibrosis (by NFS and Fib-4 scores) (P < 0.05 for all). The proportion of advanced fibrosis also increased with an increase in the number of metabolic conditions (4.1%, 25.5%, 35.6%, and 44.1% by NFS and 6.1%, 10.9%, 17%, and 26.5% by Fib-4 for no MAFLD and MAFLD with 1, 2, and 3 conditions, respectively). Among MAFLD patients, those with diabetes alone were the eldest and had the highest mean value of NFS score and Fib-4 score (P < 0.05), while MAFLD patients diagnosed with lean metabolic dysfunction exhibited the highest levels of TG and alanine aminotransferase but the lowest HDL levels (P < 0.05).

CONCLUSION

The study suggests that the severity of liver fibrosis in MAFLD patients is influenced by the number and type of metabolic conditions present. Early identification and management of MAFLD, particularly in patients with multiple metabolic conditions, are crucial to prevent liver-related complications.

Old age as a risk factor for liver diseases: Modern therapeutic approaches

Recent scientific interest has been directed towards age-related diseases, driven by the significant increase in global life expectancy and the growing population of individuals aged 65 and above. The ageing process encompasses various biological, physiological, environmental, psychological, behavioural, and social changes, leading to an augmented susceptibility to chronic illnesses. Cardiovascular, neurological, musculoskeletal, liver and oncological diseases are prevalent in the elderly. Moreover, ageing individuals demonstrate reduced regenerative capacity and decreased tolerance towards therapeutic interventions, including organ transplantation. Liver diseases, such as non-alcoholic fatty liver disease, alcoholic liver disease, hepatitis, fibrosis, and cirrhosis, have emerged as significant public health concerns. Paradoxically, these conditions remain underestimated despite their substantial global impact. Age-related factors are closely associated with the severity and unfavorable prognosis of various liver diseases, warranting further investigation to enhance clinical management and develop novel therapeutic strategies. This comprehensive review focuses specifically on age-related liver diseases, their treatment strategies, and contemporary practices. It provides a detailed account of the global burden, types, molecular mechanisms, and epigenetic alterations underlying these liver pathologies.

The impact of metabolic dysfunction-associated fatty liver disease on the prognosis of patients with hepatocellular carcinoma after radical resection

BACKGROUND

Metabolic dysfunction-associated fatty liver disease (MAFLD) is recently proposed an entity by a group of international experts. However, the impact of MAFLD on the prognosis of patients with hepatocellular carcinoma (HCC) is not clear. The aim of this study was to explore the influence of MAFLD for the prognosis of HCC after radical resection.

METHODS

HCC patients who received radical resection were enrolled. The recurrence-free survival (RFS) and overall survival (OS) were compared between MAFLD and non-MAFLD.

RESULTS

A total of 576 HCC patients were included, and among them 114 (19.8%) met the diagnostic criteria of MAFLD. The median RFS was 34.0 months in the MAFLD group and 19.0 months in the non-MAFLD group. The 1-, 3-, and 5-year RFS rates were 64.9%, 49.1% and 36.1% in the MAFLD group, which were higher than those of the non-MAFLD group (59.4%, 35.3% and 26.5%, respectively, P = 0.01). The mean OS was 57.0 months in the MAFLD group and 52.2 months in the non-MAFLD group. There was no statistical difference in OS rate between the MAFLD group and non-MAFLD group. Similar results were found in HBV-related HCC patients in the subgroup analysis. Univariate analysis revealed that MAFLD was a protective factor for RFS in HCC patients after radical resection (P < 0.05), and there was no association between MAFLD and OS rate (P > 0.05). Multivariate analysis demonstrated that MAFLD was not an independent protective factor for HCC patients with radical resection.

CONCLUSIONS

MAFLD improves RFS rate in HCC patients with radical resection, but is not an independent protective factor and not associated with OS rate.

Differential risk of 23 site-specific incident cancers and cancer-related mortality among patients with metabolic dysfunction-associated fatty liver disease: a population-based cohort study with 9.7 million Korean subjects

INTRODUCTION

Although an association between metabolic dysfunction-associated fatty liver disease (MAFLD) and cardiovascular disease or overall mortality has been reported, it is unclear whether there is an association between MAFLD and cancer incidence or mortality. We aimed to investigate the differential risk of all- and site-specific cancer incidence and mortality according to MAFLD subgroups categorized by additional etiologies of liver disease.

METHODS

Using the Korean National Health Insurance Service database, we stratified the participants into three groups: (1) single-etiology MAFLD (S-MAFLD) or MAFLD of pure metabolic origin; (2) mixed-etiology MAFLD (M-MAFLD) or MAFLD with additional etiological factor(s) (i.e., concomitant liver diseases and/or heavy alcohol consumption); and (3) non-MAFLD. Hepatic steatosis and fibrosis were defined using the fatty liver index and the BARD score, respectively. Cox proportional hazards regression was performed to estimate the risk of cancer events.

RESULTS

Among the 9,718,182 participants, the prevalence of S-MAFLD and M-MAFLD was 29.2% and 6.7%, respectively. During the median 8.3 years of follow-up, 510,330 (5.3%) individuals were newly diagnosed with cancer, and 122,774 (1.3%) cancer-related deaths occurred among the entire cohort. Compared with the non-MAFLD group, the risk of all-cancer incidence and mortality was slightly higher among patients in the S-MAFLD group (incidence, adjusted hazard ratio [aHR] = 1.03; 95% confidence interval [CI]: 1.02-1.04; mortality, aHR = 1.06; 95% CI: 1.04-1.08) and highest among patients with M-MAFLD group (incidence, aHR = 1.31; 95% CI: 1.29-1.32; mortality, aHR = 1.45; 95% CI: 1.42-1.48, respectively). The M-MAFLD with fibrosis group (BARD score ≥ 2) showed the highest relative risk of all-cancer incidence (aHR = 1.38, 95% CI = 1.36-1.39), followed by the M-MAFLD without fibrosis group (aHR = 1.09, 95% CI = 1.06-1.11). Similar trends were observed for cancer-related mortality.

CONCLUSIONS

MAFLD classification, by applying additional etiologies other than pure metabolic origin, can be used to identify a subgroup of patients with poor cancer-related outcomes.

Clinical Features of Non-Alcoholic Fatty Liver Disease in the Non-Lean Population

INTRODUCTION

The prevalence of non-alcoholic fatty liver disease (NAFLD) in non-lean patients is significantly increased, and obesity significantly increases the risk of cirrhosis and HCC in NAFLD patients. However, whether there is a difference in clinical manifestations of NAFLD between overweight and obesity remains unclear. The objective of this study was to assess the clinical and histological features of NAFLD among a non-lean population.

METHODS

Current study enrolled consecutive non-lean (body mass index [BMI] >23 kg/m2) patients with NAFLD and available liver biopsy results. Patients were stratified by BMI into two groups for the comparison of their clinical and histological variables, which included the overweight (BMI 23∼<28 kg/m2) and the obese (BMI ≥28 kg/m2). Risk factors for moderate to severe fibrosis (stage >1) were also analyzed through the logistic regression model.

RESULTS

Among 184 non-lean patients with metabolic-associated fatty liver disease enrolled, 65 and 119 were overweight and obese, respectively. Patients in the obesity group had a significantly lower level of gamma-glutamyl transpeptidase, higher levels of platelet, glucose, prothrombin time, and more common of moderate to severe inflammatory activity when compared to those in the overweight group. However, a significant low frequency of moderate to severe fibrosis was found in the obesity group versus the overweight group (19.33% vs. 40.00%, p = 0.002). Binary logistics regression analysis of fibrosis found that aspartate transaminase (AST), BMI, alanine transaminase (ALT), and cholesterol (CHOL) were independent predictors for moderate to severe fibrosis in non-lean patients with NAFLD. Compared with the traditional fibrosis-4 (AUC = 0.77) and aminotransferase to platelet ratio index (AUC = 0.79) indexes, the combined index based on AST, BMI, ALT, and CHOL was more accurate in predicting moderate to severe fibrosis in non-lean patients with NAFLD (AUC = 0.87).

CONCLUSIONS

Clinical and histological features differed between obesity and overweight patients with NAFLD. When compared to the traditional serum markers, the combination index including AST, BMI, ALT, and CHOL provided a better model to predict moderate to severe fibrosis in non-lean patients with NAFLD.

MAFLD is associated with increased all-cause mortality in low cardiovascular-risk individuals but not in intermediate to high-risk individuals

BACKGROUND AND AIMS

Metabolic-associated fatty liver disease (MAFLD) is increasingly recognized as a systematic disease rather than just a liver disease alone, which raises concerns about its long-term impact on different populations. This study aimed to clarify the effects of MAFLD on long-term outcomes among different cardiovascular risk-stratified populations.

METHODS AND RESULTS

Eligible individuals in the Third National Health and Nutrition Examination Surveys (NHANES Ⅲ, 1988-1994) were enrolled. Participants were classified into low, intermediate, or high cardiovascular-risk populations according to the Framingham general equations. Kaplan-Meier survival analysis and Cox regression models were used to investigate the association between MAFLD and long-term outcomes in different cardiovascular-risk populations. A total of 8897 adults were enrolled in the final analysis. The median ages in the non-MAFLD and MAFLD groups were 44 and 49 years old, respectively. During a median follow-up of 22.8 years, a total of 2991 deaths were recorded, including 1694 deaths (30.3%) in non-MAFLD and 1297 deaths (39.2%) in MAFLD (P < 0.001). In the low cardiovascular-risk population, MAFLD individuals had increased all-cause mortality than non-MAFLD individuals (HR = 1.206, 95% CI:1.0338-1.400, P = 0.014). However, similar results were not observed in intermediate or high-cardiovascular-risk individuals. Further analysis of cause-specific mortality suggested that MAFLD was associated with higher cancer-related mortality in the low-risk population (HR = 1.313, 95% CI:1.000-1.725, P = 0.049).

CONCLUSIONS

MAFLD was associated with increased all-cause mortality among individuals with low cardiovascular risk, rather than those with an intermediate or high cardiovascular risk.

A Bidirectional Association Between Obstructive Sleep Apnea and Metabolic-Associated Fatty Liver Disease

Obesity is considered a twentieth-century epidemic and is a growing concern among health professionals. Obesity and its complications contribute to multiple chronic illnesses, such as type 2 diabetes (T2D), metabolic syndrome, obstructive sleep apnea (OSA), malignancy, and cardiovascular and liver diseases. In the last two decades, a bidirectional association between OSA and metabolic-associated fatty liver disease (MAFLD), independent of obesity, has been established. Both conditions have similar risk factors and metabolic comorbidities that may imply a common disease pathway. This review compiles the evidence and delineates the relationship between OSA and MAFLD from a clinical and diagnostic aspect.

Screening for MAFLD: who, when and how?

Metabolic-associated fatty liver disease (MAFLD) is a highly prevalent disease with increasing prevalence worldwide. Currently, no universal screening methods have been standardized, even when this disease poses a major health burden. MAFLD as a spectrum of diseases can range from simple steatosis, and steatohepatitis to fibrosis and hepatocellular carcinoma. Its extra-hepatic manifestations are vast and include cardiovascular diseases, extra-hepatic malignancies, cognitive and respiratory alterations. Given its extensive damage targets as well as its high prevalence, timely identification of the high-risk population presenting metabolic dysfunction should undergo universal non-invasive screening methods, which can be carried out through blood tests, easy and effective imaging techniques, such as ultrasound, score calculation and general clinical information brought together from primary patient-physician contact.

Correlation between thyroid function, sensitivity to thyroid hormones and metabolic dysfunction-associated fatty liver disease in euthyroid subjects with newly diagnosed type 2 diabetes

PURPOSE

To estimate the prevalence of metabolic dysfunction-associated fatty liver disease (MAFLD) and to evaluate the associations between thyroid parameters, MAFLD and liver fibrosis in euthyroid patients with newly diagnosed type 2 diabetes mellitus (T2DM).

METHODS

Overall, 776 patients with newly diagnosed T2DM and 120 subjects without diabetes were included. All the participants were euthyroid, and were categorized as non-MAFLD and MAFLD. Demographic information, biochemical parameters, and serum thyroid hormones were collected. The thyroid hormone sensitivity indices were calculated. MAFLD was defined according to abdominal ultrasound and clinical manifestations. Noninvasive fibrosis indices were calculated to identify advanced liver fibrosis.

RESULTS

The prevalence of MAFLD was significantly higher in patients with T2DM than in subjects without diabetes. Levels of free triiodothyronine (FT3) and FT3 to free thyroxine (FT4) ratio were significantly higher in subjects with MAFLD. In patients with T2DM, levels of thyroid stimulating hormone (TSH), Thyroid feedback quantile-based index (TFQI_FT3) calculated using FT3 and TSH, thyrotroph T3 resistance index (TT3RI) and thyrotroph T4 resistance index (TT4RI) were significantly higher in subjects with MAFLD. The prevalence of MAFLD increased with the rise of FT3, FT3/FT4, TSH, and sensitivity to thyroid hormone indices (TFQI_FT3, TT3RI, and TT4RI). But significant correlations were not found between thyroid hormones, sensitivity to thyroid hormones and MAFLD, after adjustment for BMI and HOMA-IR. The incidence of advanced fibrosis tended to increase as the rise of TSH and sensitivity to thyroid hormone indices (TFQI_FT3, TT3RI, TT4RI, and TSHI).

CONCLUSION

MAFLD was prevalent in euthyroid patients with newly diagnosed T2DM. Higher normal FT3, TSH and impaired sensitivity to thyroid hormones are associated with increased incidence of MAFLD, being dependent on other metabolic factors.

Metabolic Dysfunction-Associated Fatty Liver Disease in the National Health and Nutrition Examination Survey 2017-2020: Epidemiology, Clinical Correlates, and the Role of Diagnostic Scores

The recent establishment of metabolic dysfunction-associated fatty liver disease (MAFLD) has led to a reevaluation of its epidemiology, diagnosis, and clinical implications. In this study, we aimed to evaluate MAFLD's epidemiology and its association with other pathologic states and biomarkers, as well as to assess the prevalence of the different fibrosis stages in the MAFLD population, together with the importance of diagnostic scores in the preliminary determination of significant fibrosis. After analyzing the National Health and Nutrition Examination Survey (NHANES) 2017-2020, we found a high prevalence of MAFLD, at 58.6% of the studied population. MAFLD was accompanied by numerous comorbidities, which were increasingly common in individuals with higher grades of liver fibrosis. Fatty liver index emerged as a reliable indicator of MAFLD, as well as significant fibrosis. The estimation of fatty liver index could be a reasonable addition to the evaluation of patients with metabolic risk factors and could lead a diagnosis in the absence of liver elastography or biopsy. Further studies are needed to enhance our knowledge regarding its prognosis, as well as the role of novel therapies in its prevention or regression.

Nonalcoholic Fatty Liver Disease-A Concise Review of Noninvasive Tests and Biomarkers

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide, with a continuously growing prevalence. The pathophysiology of the disease is complex and includes several mechanisms, with metabolic syndrome and insulin resistance playing a major role. It is crucial to diagnose NAFLD before it advances to nonalcoholic steatohepatitis (NASH), which can progress to cirrhosis, presented by its complications which include ascites, portal hypertension, bleeding varices and encephalopathy. Another important complication of NAFLD and cirrhosis is hepatocellular carcinoma (HCC), a cancer with increasing incidence and poor prognosis. Even with the growing prevalence of NAFLD, diagnosis via liver biopsies is unrealistic, considering the costs and complications. Noninvasive tests, including serum biomarkers and elastography, are cost-effective and convenient, thereby replacing liver biopsies in diagnosing and excluding liver fibrosis. However, currently, these noninvasive tests have several limitations, such as variability, inadequate accuracy and risk factors for error. The limitations and variability of these tests comet the investigator to propose combining them in diagnostic algorithms to produce more accurate tools. Identifying patients with significant fibrosis is important for targeted therapies to prevent disease progression. Effective screening using noninvasive tests can be crucial for patient risk stratification and early diagnosis.

Validation of Non-invasive Fibrosis Scores for Predicting Advanced Fibrosis in Metabolic-associated Fatty Liver Disease

BACKGROUND AND AIMS

Metabolic-associated fatty liver disease (MAFLD) is a newly proposed terminology from 2020; yet, the applicability of conventional noninvasive fibrosis models is still unknown for it. We aimed to evaluate the performance of conventional noninvasive fibrosis scores in MAFLD.

METHODS

The NHANES 2017-2018 datasets were used to compare the performances of different noninvasive fibrosis scores in MAFLD, including the aspartate aminotransferase (AST) to platelet ratio index (APRI), body mass index (BMI)-AST/alanine aminotransferase (ALT) ratio and diabetes score (BARD), fibrosis-4 index (FIB-4), and NAFLD fibrosis score (NFS). Moreover, Asian patients with biopsy-proven MAFLD were enrolled to further validate the findings.

RESULTS

A total of 2,622 participants in the National Health and Nutrition Examination Survey (NHANES) cohort and 293 patients with MAFLD in the Asian cohort were included. Patients in the Asian cohort had a lower BMI and higher liver enzymes (p<0.001). The area under the receiver operating characteristic curve (AUROC) of NFS was the largest in the NHANES cohort and Asian cohorts (0.679 and 0.699, respectively). The AUROC of NFS was followed by APRI, FIB-4, and BARD in the NHANES cohort (0.616, 0.601, and 0.589, respectively). In the Asian cohort, the AUROC of APRI, FIB-4, and BARD for predicting advanced fibrosis were 0.625, 0.683, and 0.615, respectively. The performance of FIB-4 was better in the Asian cohort than that in the NHANES cohort.

CONCLUSIONS

NFS is better for predicting advanced fibrosis in MAFLD. FIB-4 can be an alternative choice for MAFLD with high liver enzymes when NFS is unavailable. Novel efficient noninvasive fibrosis scoring systems are highly required for patients with MAFLD.

Global Prevalence and Clinical Characteristics of Metabolic-associated Fatty Liver Disease: A Meta-Analysis and Systematic Review of 10 739 607 Individuals

BACKGROUND AND AIMS

Metabolic-associated fatty liver disease (MAFLD) was proposed as a better definition of nonalcoholic fatty liver disease (NAFLD) to encompass the metabolic dysregulation associated with NAFLD. This redefinition challenges our understanding of the disease. Hence, this study sought to conduct an updated analysis of the prevalence, clinical characteristics, and associated factors of MAFLD, with a further sensitivity analysis done based on lean and nonobese MAFLD individuals.

METHODS

Medline and Embase databases were searched to include articles on MAFLD. Meta-analysis of proportions was conducted using the generalized linear mix model. Associating factors were evaluated in conventional pairwise meta-analysis with sensitivity analysis on lean and nonobese MAFLD.

RESULTS

From pooled analysis involving 3 320 108 individuals, the overall prevalence of MAFLD was 38.77% (95% CI 32.94% to 44.95%); 5.37% (95% CI 4.36% to 6.59%) and 29.78% (95% CI 26.06% to 33.79%) of lean and nonobese individuals, respectively, had MAFLD. Metabolic complications such as hypertension [odds ratio (OR) 2.63, 95% CI 1.85 to 3.74, P < 0.0001 and OR 2.03; 95% CI 1.74 to 2.38, P < 0.0001, respectively] and diabetes (OR 3.80, 95% CI 2.65 to 5.43, P < 0.0001 and OR 3.46, 95% CI 2.81 to 4.27, P < 0.0001, respectively) were found as significant associating factors associated with lean and nonobese MAFLD.

CONCLUSIONS

This meta-analysis supports previous studies in reporting MAFLD to affect more than a third of the global population. While exploration of the pathogenic basis of fatty liver disease without metabolic dysregulation is required, the emphasis on management of concomitant metabolic disease in MAFLD can improve multidisciplinary efforts in managing the complex disease.

Noninvasive fibrosis tools in NAFLD: validation of APRI, BARD, FIB-4, NAFLD fibrosis score, and Hepamet fibrosis score in a Portuguese population

OBJECTIVES

The burden of non-alcoholic fatty liver disease (NAFLD) is increasing, with an estimated prevalence in Europe of 20-30%. Although most patients present with simple steatosis, some progress to advanced fibrosis, cirrhosis, and hepatocellular carcinoma. Definite diagnosis and staging require liver biopsy, which is not feasible given the high prevalence of NAFLD. As such, several non-invasive tools have been formulated. However, to date, none have been validated in the Portuguese population. The aim of this study was to determine the diagnostic accuracy of the aspartate aminotransferase to platelet ratio (APRI), the BMI, AST/ALT ratio and Diabetes (BARD), the FIB-4 index (FIB-4), the Hepamet fibrosis score (HFS), and the NAFLD fibrosis score (NFS) in a Portuguese population.

METHODS

A retrospective review of liver biopsies from two hospital centers was performed. Patients with NAFLD and no decompensated cirrhosis, liver cancer or terminal illness were included. APRI, BARD, FIB-4, HFS and NFS were calculated for each patient.

RESULTS

A total of 121 individuals were included, of which 21.5% had advanced fibrosis (F≥3). There was a moderate or high correlation between most tools. The negative predictive factor (NPV) and area under receiver operating curve (AUROC) were 89.9% and 0.80 for APRI, 91.8% and 0.84 for BARD, 95.7% and 0.88 for FIB-4, 96.4% and 0.88 for HFS, and 93.0% and 0.86 for NFS, respectively.

CONCLUSION

The tools analyzed had excellent performance (AUROC ≥0.80) and were adequate for ruling out advanced fibrosis (NPV ≥89.9%) in a Portuguese population. As such, they are adequate to use in clinical practice or as a part of referral and follow-up programs wherever this population is treated.

Comments on validation of conventional non-invasive fibrosis scoring systems in patients with metabolic associated fatty liver disease

To evaluate and predict liver fibrosis in patients with nonalcoholic fatty liver disease (NAFLD), several non-invasive scoring systems were built and widely used in the progress of diagnosis and treatment, which showed great diagnostic efficiency, such as aspartate aminotransferase to platelet ratio index, fibrosis-4 index, body mass index, aspartate aminotransferase to alanine aminotransferase ratio, diabetes score and NAFLD fibrosis score. Since the new concept of metabolic associated fatty liver disease (MAFLD) was proposed, the clinical application value of the non-invasive scoring systems mentioned above has not been assessed in MAFLD. The evaluation of the diagnostic performance of these non-invasive scoring systems will provide references for clinicians in the diagnosis of MAFLD.

Epidemiology, natural history, and diagnosis of metabolic dysfunction-associated fatty liver disease: a comparative review with nonalcoholic fatty liver disease

Metabolic (dysfunction)-associated fatty liver disease (MAFLD) is the most common chronic liver disease worldwide - with an estimated global prevalence of 37%. Different from nonalcoholic fatty liver disease (NAFLD), which is an exclusion diagnosis, MAFLD is defined by a set of positive criteria. This recent change in terminology is challenging because MAFLD and NAFLD denote two similar, albeit not identical, clinical populations. When the diagnostic criteria for MAFLD are applied, liver histology appears more severe and clinical outcomes are less favorable. However, the clinical management of MAFLD and NAFLD remains similar. While liver biopsy is still the reference standard for achieving a final diagnosis, noninvasive imaging- or biomarker-based diagnostic modalities are currently gaining momentum. However, liver biopsy should be recommended when diagnostic challenges exist. In this review, we compared the epidemiology, natural history, and diagnosis of MAFLD with respect to the traditional NAFLD definition.

High liver fibrosis scores in metabolic dysfunction-associated fatty liver disease patients are associated with adverse atrial remodeling and atrial fibrillation recurrence following catheter ablation

BACKGROUND

A number of epidemiological studies have suggested an association between metabolic dysfunction-associated fatty liver disease (MAFLD) and the incidence of atrial fibrillation (AF). However, the pathogenesis leading to AF in the context of MAFLD remains unclear. We therefore aimed at assessing the impact of MAFLD and liver fibrosis status on left atrium (LA) structure and function.

METHODS

Patients with a Fatty Liver Index (FLI) >60 and the presence of metabolic comorbidities were classified as MAFLD+. In MAFLD+ patients, liver fibrosis severity was defined using the non-alcoholic fatty liver disease (NAFLD) Fibrosis Score (NFS), as follows: MAFLD w/o fibrosis (NFS ≦ -1.455), MAFLD w/indeterminate fibrosis (-1.455 < NFS < 0.675), and MAFLD w/fibrosis (NFS ≧ 0.675). In the first cohort of patients undergoing AF ablation, the structural and functional impact on LA of MAFLD was assessed by LA strain analysis and endocardial voltage mapping. Histopathological assessment of atrial fibrosis was performed in the second cohort of patients undergoing cardiac surgery. Finally, the impact of MAFLD on AF recurrence following catheter ablation was assessed.

RESULTS

In the AF ablation cohort (NoMAFLD n = 123; MAFLD w/o fibrosis n = 37; MAFLD indeterm. fibrosis n = 75; MAFLD w/severe fibrosis n = 10), MAFLD patients with high risk of F3-F4 liver fibrosis presented more LA low-voltage areas as compared to patients without MAFLD (16.5 [10.25; 28] vs 5.0 [1; 11] low-voltage areas p = 0.0115), impaired LA reservoir function assessed by peak left atrial longitudinal strain (19.7% ± 8% vs 8.9% ± 0.89% p = 0.0268), and increased LA volume (52.9 ± 11.7 vs 43.5 ± 18.0 ml/m² p = 0.0168). Accordingly, among the MAFLD patients, those with a high risk of F3-F4 liver fibrosis presented a higher rate of AF recurrence during follow-up (p = 0.0179). In the cardiac surgery cohort (NoMAFLD n = 12; MAFLD w/o fibrosis n = 5; MAFLD w/fibrosis n = 3), an increase in histopathological atrial fibrosis was observed in MAFLD patients with a high risk of F3-F4 liver fibrosis (p = 0.0206 vs NoMAFLD; p = 0.0595 vs MAFLD w/o fibrosis).

CONCLUSION

In conclusion, we found that liver fibrosis scoring in MAFLD patients is associated with adverse atrial remodeling and AF recurrences following catheter ablation. The impact of the management of MAFLD on LA remodeling and AF ablation outcomes should be assessed in dedicated studies.