Type 2 diabetes mellitus and cardiometabolic outcomes in metabolic dysfunction-associated steatotic liver disease population

The metabolic syndrome, characterized by type 2 diabetes mellitus (T2DM), hypertension, hyperlipidemia, and obesity, collectively increases the risk of cardiovascular diseases. Nonalcoholic fatty liver disease (NAFLD) is a prominent manifestation, affecting over a third of the global population with a concerning annual increase in prevalence. Nearly 70 % of overweight individuals have NAFLD, and NAFLD-related deaths are predicted to rise, especially among young adults. The association of T2DM and NAFLD has led to the proposal of "metabolic dysfunction-associated steatotic liver disease" (MASLD) terminology, encompassing individuals with T2DM, overweight/obesity, hypertension, hypertriglyceridemia, or low HDL-cholesterol. Patients with MASLD will likely have double the risk of developing T2DM, and the combination of insulin resistance, overweight/obesity, and MASLD significantly elevates the risk of T2DM. Cardiovascular diseases remain the leading cause of mortality in the MASLD and T2DM population, with MASLD directly associated with coronary artery disease, compounded by coexisting insulin resistance and T2DM. Urgency lies in early detection of subclinical cardiovascular diseases among patients with T2DM and MASLD. Novel strategies targeting multiple pathways offer hope for effectively improving cardiometabolic health. Understanding and addressing the intertwined factors contributing to these disorders can pave the way towards better management and prevention of cardiometabolic complications.

Natural Products in the Modulation of Farnesoid X Receptor Against Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is a global health concern with a high prevalence and increasing economic burden, but official medicine remains unavailable. Farnesoid X receptor (FXR), a nuclear receptor member, is one of the most promising drug targets for NAFLD therapy that plays a crucial role in modulating bile acid, glucose, and lipid homeostasis, as well as inhibits hepatic inflammation and fibrosis. However, the rejection of the FXR agonist, obecholic acid, by the Food and Drug Administration for treating hepatic fibrosis raises a question about the functions of FXR in NAFLD progression and the therapeutic strategy to be used. Natural products, such as FXR modulators, have become the focus of attention for NAFLD therapy with fewer adverse reactions. The anti-NAFLD mechanisms seem to act as FXR agonists and antagonists or are involved in the FXR signaling pathway activation, indicating a promising target of FXR therapeutic prospects using natural products. This review discusses the effective mechanisms of FXR in NAFLD alleviation, and summarizes currently available natural products such as silymarin, glycyrrhizin, cycloastragenol, berberine, and gypenosides, for targeting FXR, which can facilitate development of naturally targeted drug by medicinal specialists for effective treatment of NAFLD.

Antimullerian Hormone, a Marker of Ovarian Reserve, Is Protective Against Presence and Severity of NASH in Premenopausal Women

BACKGROUND & AIMS

Antimüllerian hormone (AMH) is a marker of ovarian reserve with emerging data linking lower levels to some metabolic and inflammatory diseases in women. Whether AMH levels influence nonalcoholic fatty liver disease (NAFLD) is unknown.

METHODS

Leveraging the NASH Clinical Research Network we determined the association of AMH levels within 6 months of liver biopsy with presence and severity of histologic measures of NAFLD in premenopausal women. Outcomes included presence of nonalcoholic steatohepatitis (NASH), presence and severity of fibrosis, and NAFLD Activity Score and its components. Logistic and ordinal logistic regression models were adjusted for age, race/ethnicity, homeostatic model assessment for insulin resistance, body mass index, dyslipidemia, polycystic ovary syndrome, estrogen-progestin use, and menstrual cyclicity.

RESULTS

Median cohort age was 35 years; 73% were white and 24% Hispanic. Thirty-three percent had diabetes, 81% had obesity, and 95% had dyslipidemia. On biopsy 71% had NASH, 68% had any fibrosis, and 15% had advanced fibrosis. On adjusted analysis (n = 205), higher AMH quartiles were inversely associated with NAFLD histology including prevalent NASH (adjusted odds ratio [AOR], 0.64; 95% confidence interval [CI], 0.41-1.00), NAFLD Activity Score ≥5 (AOR, 0.52; 95% CI, 0.35-0.77), Mallory hyaline (AOR, 0.54; 95% CI, 0.35-0.82), and higher fibrosis stage (AOR, 0.70; 95% CI, 0.51-0.98). The protective effects of AMH were more pronounced among women without polycystic ovary syndrome (n = 164), including lower odds of NASH (AOR, 0.53; 95% CI, 0.32-0.90) and any NASH fibrosis (AOR, 0.54; 95% CI, 0.32-0.93).

CONCLUSIONS

AMH may reflect a unique biomarker of NASH in premenopausal women and findings suggest a novel link between reproductive aging and histologic severity of NAFLD in women.

Atorvastatin on Treatment of Nonalcoholic Fatty Liver Disease Patients

Non-alcoholic fatty liver disease (NAFLD) is a condition in which excess fat builds up in the liver, often related to obesity and insulin resistance, which can lead to inflammation and scarring of the liver tissue. While efforts have been made to develop effective treatments for NAFLD, the need for pharmaceutical interventions remains unmet. Large clinical trials investigating the association between statin use and NAFLD are scarce, leading to contradictory results. Statins play a crucial role in cholesterol synthesis in the liver. Several studies have demonstrated that statins possess anti-inflammatory, anti-thrombotic, and anti-fibrotic properties. These properties make statins potentially useful in preventing the progression of NAFLD from simple steatosis to more severe forms like non-alcoholic steatohepatitis (NASH) and fibrosis. The results indicate that statin use is associated with a lower prevalence of NASH and fibrosis and may have a preventive effect on NAFLD.

Risk of Severe Infection in Patients With Biopsy-proven Nonalcoholic Fatty Liver Disease - A Population-based Cohort Study

BACKGROUND & AIMS

It has been suggested that patients with nonalcoholic fatty liver disease (NAFLD) might be at increased risk of severe infections, but large-scale data from cohorts with biopsy-proven NAFLD are lacking.

METHODS

Population-based cohort study including all Swedish adults with histologically confirmed NAFLD (n = 12,133) from 1969 to 2017. NAFLD was defined as simple steatosis (n = 8232), nonfibrotic steatohepatitis (n = 1378), noncirrhotic fibrosis (n = 1845), and cirrhosis (n = 678). Patients were matched to ≤5 population comparators (n = 57,516) by age, sex, calendar year, and county. Swedish national registers were used to ascertain incident severe infections requiring hospital admission. Multivariable adjusted Cox regression was used to estimate hazard ratios in NAFLD and histopathological subgroups.

RESULTS

Over a median of 14.1 years, 4517 (37.2%) patients with NAFLD vs 15,075 (26.2%) comparators were hospitalized for severe infections. Patients with NAFLD had higher incidence of severe infections than comparators (32.3 vs. 17.0/1000 person-years; adjusted hazard ratio [aHR], 1.71; 95% confidence interval, 1.63-1.79). The most frequent infections were respiratory (13.8/1000 person-years) and urinary tract infections (11.4/1000 person-years). The absolute risk difference at 20 years after NAFLD diagnosis was 17.3%, equal to one extra severe infection in every 6 patients with NAFLD. Risk of infection increased with worsening histological severity of NAFLD (simple steatosis [aHR, 1.64], nonfibrotic steatohepatitis [aHR, 1.84], noncirrhotic fibrosis [aHR, 1.77], and cirrhosis [aHR, 2.32]. Also compared with their full siblings, patients with NAFLD were at increased risk of severe infections (aHR, 1.54; 95% confidence interval, 1.40-1.70).

CONCLUSIONS

Patients with biopsy-proven NAFLD were at significantly higher risk of incident severe infection requiring hospitalization both compared with the general population and compared with siblings. Excess risk was evident across all stages of NAFLD and increased with worsening disease severity.

Fibrosis-4 Index Predicts Long-Term All-Cause, Cardiovascular and Liver-Related Mortality in the Adult Korean Population

BACKGROUND & AIMS

Associations between hepatic fibrosis and mortality remain to be fully elucidated in large population-based studies. This study aimed to evaluate the associations of the fibrosis-4 index (FIB-4) with all-cause, cardiovascular, cancer, and liver-related mortality in the adult Korean population without viral hepatitis.

METHODS

Baseline data were retrieved from the Korea National Health and Nutrition Examination Survey, and mortality data were retrieved from the Korean Cause of Death data registry. Adults (age, ≥19 y) without viral hepatitis B or C, liver cirrhosis, any cancer, stroke, myocardial infarction, angina pectoris, or renal failure at baseline were eligible. Presumed hepatic fibrosis was evaluated with FIB-4. Hazard ratios (HRs) and 95% CIs were calculated using multivariable Cox regression analysis, and Kaplan-Meier estimates of the cumulative mortality were evaluated.

RESULTS

There were 46,456 individuals with a median follow-up period of 8.6 years (interquartile range, 6.3-10.6 y). Kaplan-Meier curves for cumulative mortality showed that participants with a FIB-4 of ≥2.67 (vs FIB-4, <2.67) had higher cumulative all-cause, cardiovascular, cancer, and liver-related mortality. In the fully adjusted model, Cox regression analysis revealed that presumed advanced hepatic fibrosis (FIB-4, ≥2.67) remained associated with all-cause mortality (HR, 1.64; 95% CI, 1.23-2.18), cardiovascular mortality (HR, 2.96; 95% CI, 1.60-5.46), and liver-related mortality (HR, 10.50; 95% CI, 4.70-23.44), but not cancer mortality, after adjusting for confounders including central obesity and insulin resistance. Excluding participants with an estimated alcohol intake of 30 grams or more for men and 20 grams or more for women did not affect the results.

CONCLUSIONS

At the population level, liver fibrosis estimated by FIB-4 was associated with increased cumulative all-cause, cardiovascular, and liver-related mortality.

Nonheavy Alcohol Use Associates With Liver Fibrosis and Nonalcoholic Steatohepatitis in the Framingham Heart Study

BACKGROUND AND AIMS

While heavy alcohol use consistently associates with liver disease, the effects of nonheavy alcohol consumption are less understood. We aimed to investigate the relationship between nonheavy alcohol use and chronic liver disease.

METHODS

This cross-sectional study included 2629 current drinkers in the Framingham Heart Study who completed alcohol use questionnaires and transient elastography. We defined fibrosis as liver stiffness measurement (LSM) ≥8.2 kPa. We defined at-risk nonalcoholic steatohepatitis (NASH) as FibroScan-aspartate aminotransferase (FAST) score >0.35 (90% sensitivity) or ≥0.67 (90% specificity). We performed logistic regression to investigate associations of alcohol use measures with fibrosis and NASH, adjusting for sociodemographic and metabolic factors. Subgroup analysis excluded heavy drinkers (>14 drinks per week for women or >21 for men).

RESULTS

In this sample (mean age 54.4 ± 8.9 years, 53.3% women), mean LSM was 5.6 ± 3.4 kPa, 8.2% had fibrosis, 1.9% had NASH by FAST ≥0.67, and 12.4% had NASH by FAST >0.35. Participants drank 6.2 ± 7.4 drinks per week. Total drinks per week and frequency of drinking associated with increased odds of fibrosis (adjusted odds ratio [aOR], 1.18; 95% confidence interval [CI], 1.04-1.33; and aOR, 1.08; 95% CI, 1.01-1.16, respectively). Risky weekly drinking, present in 17.4%, also associated with fibrosis (aOR, 1.49; 95% CI, 1.03-2.14). After excluding 158 heavy drinkers, total drinks per week remained associated with fibrosis (aOR, 1.16; 95% CI, 1.001-1.35). Multiple alcohol use measures positively associated with FAST >0.35.

CONCLUSIONS

In this community cohort, we demonstrate that nonheavy alcohol use associates with fibrosis and NASH, after adjustment for metabolic factors. Longitudinal studies are needed to determine the benefits of moderating alcohol use to reduce liver-related morbidity and mortality.

Prevalence of Nonalcoholic Fatty Liver Disease in Patients With Rheumatoid Arthritis: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Previous studies have shown a potential association between nonalcoholic fatty liver disease (NAFLD) and some immune-mediated inflammatory diseases, such as rheumatoid arthritis (RA), but this association has not been analyzed systematically. Therefore, we aimed to perform a systematic review and meta-analysis to ascertain a pooled prevalence estimate of NAFLD among patients with RA to fill this gap in knowledge.

METHODS

We conducted a literature search in PubMed, Embase, Web of Science, Scopus, and ProQuest, for observational studies published from inception to August 31, 2022, which reported prevalence of NAFLD in 100 or more adult (age, ≥18 y) patients with RA. To be included, NAFLD diagnosis was based on either imaging or histologic assessment. The results were presented as pooled prevalence, odds ratio, and 95% CI. The I2 statistic was used to measure the heterogeneity between studies.

RESULTS

This systematic review included 9 eligible studies derived from 4 continents comprising 2178 patients (78.8% women) with RA. The pooled prevalence of NAFLD was 35.3% (95% CI, 19.9-50.6; I2 = 98.6%; P < .001) in patients with RA. All studies used ultrasound for the diagnosis of NAFLD, except for 1 study that used transient elastography. The pooled prevalence of NAFLD in men with RA was significantly higher than in women with RA (35.2%; 95% CI, 24.0-46.5 compared with 22.2%; 95% CI, 17.9-26.58; P for interaction = .048). Each 1-unit increase in body mass index was associated directly with a 24% increased risk of NAFLD in RA patients (adjusted odds ratio, 1.24; 95% CI, 1.17-1.31; I2 = 0.0%; P = .518).

CONCLUSIONS

Based on this meta-analysis, 1 in 3 patients with RA had NAFLD, which appears comparable with its overall prevalence among the general population. Clinicians should actively screen for NAFLD in patients with RA.

Sarcopenia Among Patients With Nonalcoholic Fatty Liver Disease (NAFLD) Is Associated With Advanced Fibrosis

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) and sarcopenia can be associated with advanced liver disease. Our aim was to assess the association between sarcopenia and the risk of fibrosis among patients with NAFLD.

METHODS

We used the National Health and Nutrition Examination Survey (2017-2018). NAFLD was defined by transient elastography without other causes of liver disease or excessive alcohol use. Significant fibrosis (SF) and advanced fibrosis (AF) were defined by liver stiffness greater than 8.0 kPa and greater than 13.1 kPa, respectively. Sarcopenia was defined using the Foundation for the National Institutes of Health definition.

RESULTS

Of the total cohort (N = 2422), 18.9% had sarcopenia, 9.8% had obese sarcopenia, 43.6% had NAFLD, 7.0% had SF, and 2.0% had AF. Moreover, 50.1% had neither sarcopenia nor NAFLD, 6.3% had sarcopenia without NAFLD, 31.1% had NAFLD without sarcopenia, and 12.5% had NAFLD with sarcopenia. Compared with individuals without NAFLD or sarcopenia, individuals with sarcopenic NAFLD had higher rates of SF (18.3% vs 3.2%) and AF (7.1% vs 0.2%). In the absence of sarcopenia, compared with individuals without NAFLD, individuals with NAFLD have a significantly increased risk of SF (odds ratio, 2.18; 95% CI, 0.92-5.19). In the presence of sarcopenia, NAFLD was associated with an increased risk of SF (odds ratio, 11.27; 95% CI, 2.79-45.56). This increase was independent of metabolic components. The proportion of SF that is attributable to the interaction of NAFLD and sarcopenia was 55% (attributable proportion, 0.55; 95% CI, 0.36-0.74). Increased leisure time physical activity was associated with a lower risk of sarcopenia.

CONCLUSIONS

Patients with sarcopenic NAFLD are at risk for SF and AF. Increased physical activity and a healthy diet targeted to improve sarcopenic NAFLD could reduce the risk of significant fibrosis.

The Association between Circulating Adipocytokine Omentin Levels and Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-analysis

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver condition worldwide. NAFLD is often associated with features of Metabolic Syndrome such as obesity and insulin resistance.

METHOD

The current comprehensive meta-analysis was performed to evaluate the association between circulating Omentin levels and NAFLD. A systematic search in Scopus, Web of Science, PubMed, and Google Scholar databases was conducted to identify relevant studies up until 5th May 2022. The standard mean difference (SMD) values and 95% confidence intervals (CIs) were computed for the association of Omentin levels with NAFLD risk in a random effect model.

RESULT

The meta-analysis involved 6 case-control studies with a total of 371 cases and 269 controls. Pooled SMD showed no significant difference in serum Omentin between NAFLD and healthy groups (SMD= -0.047 and 95% CI -0.957_0.862 P=0.91). Subgroup analysis based on sample size showed that the average Omentin levels were significantly higher in NAFLD patients in studies with sample size ≥70 (SMD=0.356 CI 0.056_0.655 P=0.02).

CONCLUSION

Additional well-designed studies with more sample sizes are essential to clarify the potential role of Omentin as a risk marker of NAFLD.

Mortality and Liver-Related Events in Lean Versus Non-Lean Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Although approximately 40% of patients with nonalcoholic fatty liver disease (NAFLD) are nonobese or lean, little is known about the long-term clinical outcomes of lean NAFLD. We aimed to estimate the risk of mortality and adverse liver-related events in patients with lean NAFLD compared with those with non-lean NAFLD.

METHODS

We searched the PubMed, Embase, and Cochrane Library databases through May 2022 for articles reporting mortality and/or development of cirrhosis among lean and non-lean NAFLD patients. The relative risks (RRs) of all-cause mortality, cardiovascular mortality, liver-related mortality, and occurrence of decompensated cirrhosis or hepatocellular carcinoma were pooled using the random-effects model. We also performed subgroup analysis according to characteristics of the study population, methods of NAFLD diagnosis, study design, study region, and length of follow-up.

RESULTS

We analyzed 10 cohort studies involving 109,151 NAFLD patients. Patients with lean NAFLD had comparable risks for all-cause mortality (RR, 1.09; 95% confidence interval [CI], 0.66-1.90), cardiovascular mortality (RR, 1.12; 95% CI, 0.66-1.90), and adverse liver events including decompensated cirrhosis and hepatocellular carcinoma (RR, 0.81; 95% CI, 0.50-1.30). However, the risk of liver-related mortality was higher in patients with lean than non-lean NAFLD (RR, 1.88; 95% CI, 1.02-3.45).

CONCLUSIONS

This study highlights a higher risk of liver-related mortality in patients with lean NAFLD than those with non-lean NAFLD. This finding indicates that further understanding of the pathophysiology, risk factors of adverse outcomes, and genetic and ethnic variabilities of lean NAFLD phenotype is warranted for individualized treatment strategies in lean NAFLD patients.

The Spectrum and Impact of Metabolic Dysfunction in MAFLD: A Longitudinal Cohort Analysis of 32,683 Overweight and Obese Individuals

BACKGROUND

Metabolic associated fatty liver disease (MAFLD) was recently proposed as an alternative name change for better encapsulation of disease. However, there exists a spectrum of MAFLD where both metabolically healthy (MH) and metabolically unhealthy (MU) individuals are included. In view of limited evidence, we sought to examine the prevalence, clinical characteristics, and differences in outcomes of MH-MAFLD at the population level.

METHODS

Data were used from the United States National Health and Nutrition Examination Survey 1999 to 2018. Multivariate logistic regression analysis was used to obtain odds ratios for the estimation of events. Survival analysis was conducted with Cox regression and the Fine-Gray subdistribution model.

RESULTS

There were 32,683 overweight and obese individuals included in the analysis. In MAFLD patients, the prevalence of MH-MAFLD was 6.92% (95% confidence interval [CI], 6.58%-7.27%), and 93.08% (95% CI, 92.73%-93.42%) were considered as MU-MAFLD. Multivariate analysis found a significantly higher risk of MACE (odds ratio, 1.38; 95% CI, 1.28-1.49; P < .01), all-cause (hazard ratio, 1.24; 95% CI, 1.17-1.32; P < .01), cardiovascular disease (SHR, 1.20; 95% CI, 1.02-1.42; P = .03), and cancer mortality (SHR, 1.24; 95% CI, 1.07-1.44; P < .01) in MU-MAFLD relative to non-MAFLD. However, MH-MAFLD individuals were not associated with a statistically significant increased risk of these adverse outcomes compared with non-MAFLD. MU-MAFLD diabetics were also at a higher risk of adverse events compared with non-diabetics.

CONCLUSIONS

This study reports on the heterogeneity and spectrum of metabolic dysfunction that exists in overweight and obese MAFLD. Although MAFLD may potentially be advantageous in improving awareness and patient outcomes, there remains substantial heterogeneity within patients included in MAFLD on the basis of the underlying metabolic burden.

Associations of Serum Uric Acid Level With Liver Enzymes, Nonalcoholic Fatty Liver Disease, and Liver Fibrosis in Korean Men and Women: A Cross-Sectional Study Using Nationally Representative Data

BACKGROUND

This study aimed to determine whether serum uric acid (SUA) levels are associated with various indices of liver damage in the adult Korean population.

METHODS

We used the Seventh (VII) Korean National Health and Nutritional Examination Surveys. Our study population comprised 6,007 men and 8,488 women. Levels of SUA were divided into four groups (≤ 5.3, 5.3-6.0, 6.0-7.0, and > 7.0 mg/dL for men and ≤ 4.0, 4.0-4.8, 4.8-6.0, and > 6.0 mg/dL for women). Elevated liver enzyme levels were defined as > 35 (men) and > 31 (women) IU/L for aspartate aminotransferase (AST), > 45 (men) and > 34 (women) IU/L for alanine aminotransferase (ALT). Hepatic steatosis index and fibrosis (FIB)-4 index was used to determine nonalcoholic fatty liver disease (NAFLD) and liver FIB, respectively. Adjusted odds ratios (aORs) were calculated by logistic regression analysis for liver enzymes, NAFLD, and liver FIB, according to the SUA level.

RESULTS

Among women, the 4.8-6.0 and > 6.0 mg/dL SUA groups showed higher ORs of elevated AST (aOR, 1.78 and 2.03; 95% confidence interval [CI], 1.37-2.32 and 1.40-2.96, respectively; P < 0.001) and the 4.0-4.8, 4.8-6.0, and > 6.0 mg/dL SUA groups showed a higher ORs of ALT elevation (aOR, 1.35, 2.26, and 2.37; 95% CI, 1.02-1.79, 1.72-2.97, and 1.60-3.50, respectively; P < 0.001) compared to the lowest level SUA group. Among women with normal ALT, > 6.0 mg/dL SUA group showed higher OR of NAFLD status (aOR, 1.52; 95% CI, 1.06-2.19). Among men and women with NAFLD, hyperuricemia showed higher ORs of liver FIB (aOR, 2.25 and 1.89; 95% CI, 1.21-4.19 and 1.09-3.27, respectively) than the lowest level SUA group.

CONCLUSION

High SUA levels may be associated with elevated liver enzymes and NAFLD, mainly in women. Even in women with normal ALT levels, SUA levels may predict the NAFLD status. Hyperuricemia may predict advanced liver FIB in both men and women with NAFLD. Further studies investigating the causal effects of SUA on liver damage are required.

Point-of-Care Noninvasive Prediction of Liver-Related Events in Patients With Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS

Individual risk prediction of liver-related events (LRE) is needed for clinical assessment of nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH) patients. We aimed to provide point-of-care validated liver stiffness measurement (LSM)-based risk prediction models for the development of LRE in patients with NAFLD, focusing on selecting patients for clinical trials at risk of clinical events.

METHODS

Two large multicenter cohorts were evaluated, 2638 NAFLD patients covering all LSM values as the derivation cohort and 679 more advanced patients as the validation cohort. We used Cox regression to develop and validate risk prediction models based on LSM alone, and the ANTICIPATE and ANTICIPATE-NASH models for clinically significant portal hypertension. The main outcome of the study was the rate of LRE in the first 3 years after initial assessment.

RESULTS

The 3 predictive models had similar performance in the derivation cohort with a very high discriminative value (c-statistic, 0.87-0.91). In the validation cohort, the LSM-LRE alone model had a significant inferior discrimination (c-statistic, 0.75) compared with the other 2 models, whereas the ANTICIPATE-NASH-LRE model (0.81) was significantly better than the ANTICIPATE-LRE model (0.79). In addition, the ANTICIPATE-NASH-LRE model presented very good calibration in the validation cohort (integrated calibration index, 0.016), and was better than the ANTICIPATE-LRE model.

CONCLUSIONS

The ANTICIPATE-LRE models, and especially the ANTICIPATE-NASH-LRE model, could be valuable validated clinical tools to individually assess the risk of LRE at 3 years in patients with NAFLD/NASH.

Escherichia coli Promotes Endothelial to Mesenchymal Transformation of Liver Sinusoidal Endothelial Cells and Exacerbates Nonalcoholic Fatty Liver Disease Via Its Flagellin

BACKGROUND＆AIMS: Gut bacteria translocate into the liver through a disrupted gut vascular barrier, which is an early and common event in the development of nonalcoholic fatty liver disease (NAFLD). Liver sinusoidal endothelial cells (LSECs) are directly exposed to translocated gut microbiota in portal vein blood. Escherichia coli, a commensal gut bacterium with flagella, is markedly enriched in the gut microbiota of patients with NAFLD. However, the impact of E coli on NAFLD progression and its underlying mechanisms remains unclear.

METHODS

The abundance of E coli was analyzed by using 16S ribosomal RNA sequencing in a cohort of patients with NAFLD and healthy controls. The role of E coli was assessed in NAFLD mice after 16 weeks of administration, and the features of NAFLD were evaluated. Endothelial to mesenchymal transition (EndMT) in LSECs induced by E coli was analyzed through Western blotting and immunofluorescence.

RESULTS

The abundance of gut Enterobacteriaceae increased in NAFLD patients with severe fat deposition and fibrosis. Importantly, translocated E coli in the liver aggravated hepatic steatosis, inflammation, and fibrosis in NAFLD mice. Mechanistically, E coli induced EndMT in LSECs through the TLR5/MYD88/TWIST1 pathway during NAFLD development. The toll-like receptor 5 inhibitor attenuated E coli-induced EndMT in LSECs and liver injury in NAFLD mice. Interestingly, flagellin-deficient E coli promoted less EndMT in LSECs and liver injury in NAFLD mice.

CONCLUSIONS

E coli promoted the development of NAFLD and promoted EndMT in LSECs through toll-like receptor 5/nuclear factor kappa B-dependent activation of TWIST1 mediated by flagellin. Therapeutic interventions targeting E coli and/or flagellin may represent a promising candidate for NAFLD treatment.

Risk Stratification for Sarcopenic Obesity in Subjects With Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS

The impact of the severity of sarcopenic obesity (SO) in nonalcoholic fatty liver disease (NAFLD) on the risk of significant liver fibrosis or cardiovascular disease (CVD) remains unclear. We aimed to identify high-risk subjects with SO for significant liver fibrosis or CVD among subjects with SO and NAFLD.

METHODS

This multicenter, retrospective study involved 23,889 subjects with NAFLD who underwent a health screening program (2014-2020). Sarcopenia was defined based on gender-specific sarcopenia index cutoff using multi-frequency bioelectric impedance analysis. High-risk subjects with SO were defined as those with significant liver fibrosis by fibrosis-4 index >2.67 or atherosclerotic CVD risk score >20%. Multivariable logistic regression analysis for identifying high-risk subjects with SO was performed in a cross-sectional cohort with SO, and further validation was performed in a longitudinal cohort.

RESULTS

SO prevalence was 5.4% (n = 1297 of 23,889). Older age (unstandardized beta [β] = 3.23; P < .001), male (β = 1.66; P = .027), sarcopenia index (β = -6.25; P = .019), and metabolic syndrome (β = 1.75; P < .001) were significant risk factors for high-risk SO. Based on a high-risk SO screening model, high-risk subjects with SO had significantly higher odds of significant liver fibrosis (training: adjusted odds ratio [aOR], 3.72; validation: aOR, 2.38) or CVD (training: aOR, 5.20; validation: aOR, 3.71) than subjects without SO (all P < .001). In subgroup analyses, the cumulative incidence of significant liver fibrosis or CVD development was significantly higher in high-risk subjects with SO than in low-risk subjects with SO in a longitudinal cohort considering all-cause mortality and liver transplantation as competing risks (sub-distribution hazard ratio, 5.37; P < .001).

CONCLUSION

The high-risk screening model may enable the identification of high-risk subjects with SO with NAFLD.

Diagnostic Performance of Noninvasive Tests for Advanced Hepatic Fibrosis in Young Age Population

BACKGROUND & AIMS

Most noninvasive tests (NITs) for hepatic fibrosis are designed for middle-aged patients with chronic liver disease. We compared the diagnostic performance of major NITs (aspartate aminotransferase-to-platelet ratio index [APRI], Fibrosis-4 index, and nonalcoholic fatty liver disease fibrosis score) for a community-based cohort.

METHODS

This cross-sectional study analyzed 8775 participants who underwent magnetic resonance elastography at community health check-up centers. Advanced hepatic fibrosis (≥F3) was defined by magnetic resonance elastography thresholds of 3.6 kPa. The diagnostic performance of 3 NITs was evaluated according to the etiology of liver disease, sex, metabolic syndrome, obesity, and increased aminotransferase levels in 4 age groups.

RESULTS

The APRI generally showed the best area under the receiver operating characteristic curve in patients aged 45 years or younger, and it was statistically significant in patients with chronic viral hepatitis and alcoholic fatty liver disease (P < .043). The best APRI cut-off value for detecting advanced hepatic fibrosis was 0.4, with a sensitivity and specificity of 75.8% and 73.5%, respectively, in the community-based cohort. The APRI showed balanced sensitivity and specificity across all age groups, whereas the other metrics showed low sensitivity in those aged <45 and low specificity in those >65 years.

CONCLUSIONS

The APRI showed better sensitivity and negative predictive value than the Fibrosis-4 index and the nonalcoholic fatty liver disease fibrosis score in community-based populations with mixed etiology, and, thus, can be performed as the primary test in young adults (age, ≤45 y).

Noninvasive Assessment of Liver Fibrosis in NAFLD

Nonalcoholic fatty liver disease (NAFLD) has emerged as a leading cause of liver-related morbidity and mortality worldwide, afflicting approximately a billion individuals. NAFLD is a slowly progressive disease that may evolve in a subset of patients toward cirrhosis, hepatocellular carcinoma, and end-stage liver disease. Liver fibrosis severity is the strongest predictor of clinical outcomes. The emergence of effective therapeutics on the horizon highlights the need to identify among patients with NAFLD, those with severe fibrosis or cirrhosis, who are the most at risk of developing complications and target them for therapy. Liver biopsy has been the reference standard for this purpose. However, it is not suitable for large-scale population evaluation, given its well-known limitations (invasiveness, rare but severe complications, and sampling variability). Thus, there have been major efforts to develop simple noninvasive tools that can be used in routine clinical settings and in drug development. Noninvasive approaches are based on the quantification of biomarkers in serum samples or on the measurement of liver stiffness, using either ultrasound- or magnetic resonance-based elastography techniques. This review provides a roadmap for future development and integration of noninvasive tools in clinical practice and in drug development in NAFLD. We discuss herein the principles for their development and validation, their use in clinical practice, including for diagnosis of NAFLD, risk stratification in primary care and hepatology settings, prediction of long-term liver-related and non-liver-related outcomes, monitoring of fibrosis progression and regression, and response to future treatment.

Development and Validation of a Questionnaire to Assess Awareness and Knowledge of Nonalcoholic Fatty Liver Disease, a Liver Cancer Etiological Factor, among Chinese Young Adults

PURPOSE

Despite the increasing prevalence of nonalcoholic fatty liver disease (NAFLD), a liver cancer etiological factor, among Chinese young adults (CYA), there is a lack of valid, reliable, ready-to-use survey instruments for assessing awareness and knowledge of NAFLD in this population. The aims of this study were to develop, validate, and assess the reliability of a web-based, self-administered questionnaire evaluating awareness and knowledge of NAFLD among CYA.

METHODS

Based on review of relevant literature, a draft questionnaire was initially developed. Face and content validity of the questionnaire was evaluated by an expert panel of seven gastroenterologists. The construct validity was tested through item analysis based on item response theory. Reliability assessment included test-retest for stability and test for internal consistency. Two pilot tests were conducted among 60 randomly selected students at Lanzhou University, China, through WeChat App.

RESULTS

The content validity and clarity indexes were both greater than 0.85. Face validity was established by concluding that questions had no issue with feasibility, readability, clarity of wording, clarity of layout, and style. Response rates for two pilot tests were 96.7% (58 out of 60) and 98.3% (59 out of 60), respectively. Results testing the construct validity showed estimated amount of information obtained by the test between -3 and +3 range of ability was 97.57%. The test-retest reliability (Pearson's r) was 0.62. The internal consistency (KR20) was 0.92.

CONCLUSIONS

This newly developed questionnaire is a reliable and valid instrument for assessing awareness and knowledge of NAFLD among this sample from CYA.

The Potential Role of Fatigue in Identifying Patients With NASH and Advanced Fibrosis Who Experience Disease Progression

BACKGROUND AND AIMS

Fatigue is common in patients with advanced liver disease. We investigated fatigue and clinical outcomes among patients with advanced nonalcoholic steatohepatitis (NASH).

METHODS

In this study, patients with biopsy confirmed NASH and bridging fibrosis (F3) or compensated cirrhosis (F4) were followed for up to 2 years. The Chronic Liver Disease Questionnaire for Nonalcoholic Steatohepatitis (CLDQ-NASH) fatigue domain at baseline (range, 1-7; lower score indicating worse fatigue) quantified fatigue. The Cox proportional hazards model was used to study time to liver-related clinical events (progression to histologic cirrhosis or hepatic decompensation in F3, hepatic decompensation in F4).

RESULTS

Of the 1679 NASH patients with fibrosis, 802 had F3 and 877 had F4 (58 ± 9 years of age, 40% male, 74% type 2 diabetes). During median follow-up of 16 months (interquartile range, 14-18), 15% (n = 123) of NASH F3 patients experienced liver-related events and 3.5% (n = 31) of NASH F4 patients experienced hepatic decompensation. Mean baseline CLDQ-NASH fatigue score in F3 patients was 4.77 ± 1.36; NASH F3 patients who experienced liver-related events had lower baseline scores: 4.47 ± 1.36 vs 4.83 ± 1.35 (P = .0091). The mean fatigue score in F4 was 4.56 ± 1.44; these scores were lower in patients who decompensated in follow-up: 3.74 ± 1.31 vs 4.59 ± 1.43 (P = .0011). The association of lower fatigue scores and risk of liver-related or decompensation events was significant after adjustment for confounders (adjusted hazard ratio per 1 point in fatigue score in F3, 0.85; 95% confidence interval, 0.74-0.97; P = .02; adjusted hazard ratio in F4, 0.62; 95% confidence interval, 0.48-0.81; P = .0004).

CONCLUSION

Worse fatigue at baseline is associated with a higher risk of adverse clinical events in patients with NASH-related advanced fibrosis and cirrhosis.

Poor Diagnostic Efficacy of Noninvasive Tests for Advanced Fibrosis in Obese or Younger Than 60 Diabetic NAFLD patients

BACKGROUND & AIMS

Serum-based noninvasive tests (NITs) have been widely used to assess liver fibrosis in patients with nonalcoholic fatty liver disease (NAFLD). However, the diagnostic efficacy of NITs across ranges of age, body mass index (BMI), and presence of type 2 diabetes (T2DM) may vary and have not been well-characterized.

METHODS

We analyzed 1489 patients with biopsy-proven NAFLD from 6 centers in Japan, Taiwan, and Korea. Using histology as the gold standard, we compared the areas under the receiver operating characteristic (AUROCs) of Fibrosis-4 index (FIB-4), NAFLD fibrosis score (NFS), and the new Hepamet fibrosis score (HFS), with a focus on performance in subgroups as stratified by age, BMI, and the presence of T2DM.

RESULTS

By histology, 44.0% of the overall cohort (655/1489) had F2-4, and 20.6% (307/1489) had F3-4 fibrosis. FIB-4 had the highest AUROCs for both F2-4 (0.701 vs NFS 0.676 and HFS 0.682, P = .001) and F3-4 (0.767 vs NFS 0.736 and HFS 0.752, P = .002). However, for F3-4 fibrosis, the AUROCs of all 3 NITs were generally higher in older (>60 years), nonobese (BMI <25 kg/m²), and non-diabetic patients, although overall the best performance was observed with FIB-4 among nonobese (BMI<25) diabetic patients (AUROC, 0.92). The worst performance was observed in younger patients with T2DM for all NITs including FIB-4 (AUROC, 0.63-0.66).

CONCLUSIONS

FIB-4 had higher diagnostic efficacy for F3-4 than NFS or HFS, but this varied greatly by age, BMI, and T2DM, with better performance in older, nonobese, and nondiabetic patients. However, all NITs including FIB-4 had unacceptably poor performance in young or obese diabetic patients.

The Effect of the Saffron Intervention on NAFLD Status and Related Gene Expression in a Rat Model

Background

According to the worldwide increasing prevalence of non-alcoholic fatty liver disease (NAFLD), the present study aimed to investigate the mechanism effects of saffron consumption on preventing NAFLD in a rat model.

Methods

In an experimental study, 12 rats were randomly divided into 2 groups to be evaluated in the prevention phase for 7 weeks. In the prevention phase, the animals were randomly assigned to either fed HFHS + 250 mg/kg saffron (S) or fed with HFHS. Afterward, parts of the liver were excised for histopathologic examination. Plasma concentrations of ALT, AST, GGT, ALP, serum lipids, insulin concentrations, plasma glucose, hs-CRP, and TAC were measured. Moreover, Also, the gene expression of 6 target genes was evaluated, including FAS, ACC1, CPT1 ،PPARα ،DGAT2, and SREBP 1-c at the beginning and end of the study. Also, the differences among groups were evaluated by the Mann-Whitney test for non-normal data and the independent t test for normal data.

Results

The prevention phase groups have a significant elevation in body weight ( P = 0.034) and food intake (P = 0.001) of the HFHS group versus HFHS + 250 mg/kg S group. Also, there was a significant difference between groups 1 and 2 for ALT (P = 0.011) and AST (P = 0.010), and TG (P = 0.040). The HFHS group had higher plasma levels of FBS (P = 0.001), insulin (P = 0.035), HOMA-IR (P = 0.032), and lower TAC (P = 0.041) versus the HFHS+ S group. Also, the difference between HFHS + 250 mg/kg S and HFHS for PPARα gene expression was significant (P = 0.030).

Conclusion

The present study showed that consumption of saffron could prevent developing NAFLD in rats at least partially through modulation in gene expression of PPARα.

Computerized Tomography-Based Screening for Moderate to Severe Hepatic Steatosis in a Multiethnic Population

Background and Aim Data on prevalence of nonalcoholic fatty liver disease in Hawaii is limited. This study determined the prevalence of moderate to severe hepatic steatosis within a multicultural, multiethnic, and multiracial cohort in Hawaii undergoing computerized tomography (CT) for reasons unrelated to fatty liver disease. Methods The authors performed a retrospective analysis of all patients who were members of an integrated health care system with CT scans including the liver between January 1, 2020, and December 31, 2020. Moderate to severe hepatic steatosis was determined by an average attenuation value < 40 Hounsfield units for non-contrast-enhanced CT and a mean attenuation value < 90 Hounsfield units for contrast-enhanced CT. Patients' electronic medical records were reviewed for existing diagnoses of hepatic steatosis, obesity, and diabetes mellitus type 2 and data to calculate a Fibrosis-4 (FIB-4) index. Results Approximately 26.6% had moderate to severe hepatic steatosis, while only 11.3% of those patients had an active diagnosis of fatty liver disease. Native Hawaiians and Pacific Islanders (33.1%) had the greatest prevalence of hepatic steatosis, followed by White people (28.4%), Asian people (27.7%), and other ethnicities (10.8%). About 61.4% patients with fatty liver had a diagnosis of obesity, while 33.4% had a body mass index < 30.0 kg/m². Finally, 86.2% patients had enough information in their electronic medical records from which to calculate a FIB-4 score and the mean FIB-4 index was 1.66 ± 3.50. Conclusions Moderate to severe hepatic steatosis is common among patients undergoing CT studies for reasons not related to hepatic steatosis in this multiethnic population most of whom did not have a diagnosis of fatty liver disease.

An Observational Data Meta-analysis on the Differences in Prevalence and Risk Factors Between MAFLD vs NAFLD

BACKGROUND & AIMS

The shift to redefine nonalcoholic fatty liver disease (NAFLD) as metabolic associated fatty liver disease (MAFLD) can profoundly affect patient care, health care professionals, and progress within the field. To date, there remains no consensus on the characterization of NAFLD vs MAFLD. Thus, this study sought to compare the differences between the natural history of NAFLD and MAFLD.

METHODS

Medline and Embase databases were searched to include articles on prevalence, risk factors, or outcomes of patients with MAFLD or NAFLD. Meta-analysis of proportions was conducted using the generalized linear mix model. Risk factors and outcomes were evaluated in conventional pairwise meta-analysis.

RESULTS

Twenty-two articles involving 379,801 patients were included. Pooled prevalence of MAFLD was 39.22% (95% confidence interval [CI], 30.96%-48.15%) with the highest prevalence in Europe and Asia, followed by North America. The current MAFLD Definition only accounted for 81.59% (95% CI, 66.51%-90.82%) of NAFLD diagnoses. Patients had increased odds of being diagnosed with MAFLD compared with NAFLD (odds ratio, 1.37; 95% CI, 1.16-1.63; P < .001). Imaging modality resulted in a significantly higher odds of being diagnosed with MAFLD compared with NAFLD, but not biopsy. MAFLD was significantly associated with males, higher body mass index, hypertension, diabetes, lipids, transaminitis, and greater fibrosis scores compared with NAFLD.

CONCLUSIONS

There were stark differences in the prevalence and risk factors between MAFLD and NAFLD. However, in the use of the MAFLD Definition, a greater emphasis on the management of concomitant metabolic diseases and a collaborative effort is required to explore the complex pathophysiologic mechanisms underlying the disease.

Association of Physical Activity With Risk of Liver Fibrosis, Sarcopenia, and Cardiovascular Disease in Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS

International guidelines recommend physical activity for subjects with nonalcoholic fatty liver disease (NAFLD). This study investigated the association of physical activity with risk of liver fibrosis, sarcopenia, and cardiovascular disease (CVD) in NAFLD.

METHODS

In this multicenter, retrospective study, 11,690 NAFLD subjects who underwent a health screening program and were assessed for physical activity (metabolic equivalent task [MET]-min/week) between 2014 and 2020 were recruited. Liver fibrosis was assessed by using the fibrosis-4 index, NAFLD fibrosis score, and FibroScan-AST score, sarcopenia by using multi-frequency bioelectric impedance analysis, and CVD risk by using atherosclerotic CVD (ASCVD) risk score, and coronary artery calcium (CAC) score were calculated.

RESULTS

The prevalence of fibrosis, sarcopenia, high probability of ASCVD, and high CAC score significantly decreased with increasing quartiles of physical activity (all P for trend <.001). In a fully adjusted model, physical activity above 600 MET-min/week (≥third quartile) was independently associated with a reduced risk of fibrosis (adjusted odds ratio [aOR] = 0.59; 95% confidence interval [CI], 0.40-0.86), sarcopenia (aOR = 0.72; 95% CI, 0.58-0.88), high probability of ASCVD (aOR = 0.58; 95% CI, 0.46-0.73), and high CAC score (aOR = 0.32; 95% CI, 0.13-0.83; all P <.05). In addition, increasing amounts of physical activity were significantly associated with risk reduction between fibrosis, sarcopenia, and high probability of ASCVD (all P for trend <.001). In subjects with sarcopenic obesity or lean NAFLD, physical activity was also independently associated with reduced risk of fibrosis and high probability of ASCVD (all P <.05).

CONCLUSIONS

Physical activity showed a protective effect against fibrosis, sarcopenia, and CVD in NAFLD.

Fenofibrate Mitigates Hypertriglyceridemia in Nonalcoholic Steatohepatitis Patients Treated With Cilofexor/Firsocostat

BACKGROUND & AIMS

Patients with advanced fibrosis due to nonalcoholic steatohepatitis (NASH) are at high risk of morbidity and mortality. We previously found that a combination of the farnesoid X receptor agonist cilofexor (CILO) and the acetyl-CoA carboxylase inhibitor firsocostat (FIR) improved liver histology and biomarkers in NASH with advanced fibrosis but was associated with hypertriglyceridemia. We evaluated the safety and efficacy of icosapent ethyl (Vascepa) and fenofibrate to mitigate triglyceride elevations in patients with NASH treated with CILO and FIR.

METHODS

Patients with NASH with elevated triglycerides (≥150 and <500 mg/dL) were randomized to Vascepa 2 g twice daily (n = 33) or fenofibrate 145 mg daily (n = 33) for 2 weeks, followed by the addition of CILO 30 mg and FIR 20 mg daily for 6 weeks. Safety, lipids, and liver biochemistry were monitored.

RESULTS

All treatments were well-tolerated; most treatment-emergent adverse events were Grade 1 to 2 severity, and there were no discontinuations due to adverse events. At baseline, median (interquartile range [IQR]) triglycerides were similar in the Vascepa and fenofibrate groups (median, 177 [IQR, 154-205] vs 190 [IQR, 144-258] mg/dL, respectively). Median changes from baseline in triglycerides for Vascepa vs fenofibrate after 2 weeks of pretreatment were -12 mg/dL (IQR, -33 to 7 mg/dL; P = .09) vs -32 mg/dL (IQR, -76 to 6 mg/dL; P = .012) and at 6 weeks were +41 mg/dL (IQR, 16-103 mg/dL; P < .001) vs -2 mg/dL (IQR, -42 to 54 mg/dL; P = .92). In patients with baseline triglycerides <250 mg/dL, fenofibrate was more effective vs Vascepa in mitigating triglyceride increases after 6 weeks of combination treatment (+6 vs +39 mg/dL); similar trends were observed in patients with baseline triglycerides ≥250 mg/d (-61 vs +99 mg/dL).

CONCLUSIONS

In patients with NASH with hypertriglyceridemia treated with CILO and FIR, fenofibrate was safe and effectively mitigated increases in triglycerides associated with acetyl-CoA carboxylase inhibition.

CLINICALTRIALS

gov, Number: NCT02781584.

Outcomes of Nonalcoholic Steatohepatitis After Liver Transplantation: An Updated Meta-Analysis and Systematic Review

BACKGROUND & AIMS

Nonalcoholic steatohepatitis (NASH) is the fastest growing indication of liver transplantation (LT) and is projected to be the leading cause of LT in the near future. The systemic pathogenesis of NASH increases risks of adverse clinical outcomes in patients with NASH receiving LT. Thus, this study aimed to conduct a time-dependent survival analysis between LT recipients with and without NASH using hazard ratios.

METHODS

A search was conducted on Medline and Embase databases for articles relating to LT outcomes for NASH recipients. A survival analysis was conducted of hazard ratios using the DerSimonian and Laird random-effects model with meta-regression. To account for censoring, survival data were reconstructed from published Kaplan-Meier curves and pooled to derive more accurate hazard estimates and all-cause mortality in NASH patients after LT. Pairwise meta-analysis was conducted to analyze secondary outcomes.

RESULTS

Fifteen studies involving 119,327 LT recipients were included in our analysis with a prevalence of NASH of 20.2% (95% CI, 12.9-30.2). The pooled 1-year, 5-year, and 10-year all-cause mortality in NASH patients after LT were 12.5%, 24.4%, and 37.9%, respectively. Overall survival was comparable between LT recipients for NASH vs non-NASH (hazard ratio, 0.910; 95% CI, 0.760 to 1.10; P = .34). Meta-regression showed that a higher model for end-stage liver disease score was associated with significantly worse overall survival in NASH compared with non-NASH after LT (95% CI, -0.0856 to -0.0181; P = .0026).

CONCLUSIONS

This study shows that patients undergoing LT for NASH cirrhosis have comparable complication rates, overall survival, and graft survival compared with non-NASH patients, although close monitoring may be indicated for those with higher model for end-stage liver disease scores.

Prevalence of High and Moderate Risk Nonalcoholic Fatty Liver Disease Among Adults in the United States, 1999-2016

BACKGROUND AND AIMS

Nonalcoholic fatty liver disease (NAFLD) subjects with fibrosis stage ≥2 are at high risk for mortality. We aimed to provide national estimates and temporal trends for NAFLD, based on different fibrosis severity.

METHODS

Data from the National Health and Nutrition Examination Survey (NHANES) (1999-2016) and NHANES III (1988-1994) were utilized. NAFLD was determined by ultrasound showing moderate to severe steatosis. For those without ultrasound, NAFLD was determined by the U.S. Fatty Liver Index score of ≥30. Hepatic fibrosis was assessed using Fibrosis-4 (FIB-4) score (FIB-4 <1.3 = low risk; FIB-4 1.3-2.67 = moderate risk; and FIB-4 >2.67 = high risk). Annual percent change (APC) was calculated by using the joinpoint regression model.

RESULTS

From NHANES III, 10,854 individuals were included (mean age 43.5 years; 47.5% male; 75.7% non-Hispanic White) and 37.7% had NAFLD. Among them, based on FIB-4, 80% had low-risk, 18.6% had moderate-risk, and 1.4% had high-risk NAFLD. NAFLD with moderate or high risk was more likely to have hypertension, hyperlipidemia, diabetes, cardiovascular disease, and metabolic syndrome than was low-risk NAFLD (all P < .02). NAFLD prevalence increased from 29.5% in 1999-2000 to 40.3% in 2015-2016 (APC, 2.78%; P < .02), moderate-risk NAFLD increased from 6.26% to 14.17% (APC, 5.34%; P < .02), and high-risk NAFLD increased from 0.49% to 1.15% (APC, 9.72%; P < .02). Independent predictors of advanced fibrosis were age (OR, 1.11; 95% CI, 1.06-1.17; P = .001) and diabetes (OR, 2.28; 95% CI, 1.03-5.05; P = .04). Compared with low-risk NAFLD, high-risk NAFLD was associated with significantly increased all-cause (HR, 1.53; 95% CI, 1.09-2.15; P = .01), cardiovascular disease-specific (HR, 1.99; 95% CI, 1.22-3.24, P < .01) and liver-specific (HR, 4.57; 95% CI, 1.03-28.79; P = .04) mortality.

CONCLUSIONS

The prevalence of moderate- or high-risk NAFLD is increasing and is associated with increased all-cause, liver-related, and cardiovascular mortality.

2019 Global NAFLD Prevalence: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

The increasing rates of obesity and type 2 diabetes mellitus may lead to increased prevalence of nonalcoholic fatty liver disease (NAFLD). We aimed to determine the current and recent trends on the global and regional prevalence of NAFLD.

METHODS

Systematic search from inception to March 26, 2020 was performed without language restrictions. Two authors independently performed screening and data extraction. We performed meta-regression to determine trends in NAFLD prevalence.

RESULTS

We identified 17,244 articles from literature search and included 245 eligible studies involving 5,399,254 individuals. The pooled global prevalence of NAFLD was 29.8% (95% confidence interval [CI], 28.6%-31.1%); of these, 82.5% of included articles used ultrasound to diagnose NAFLD, with prevalence of 30.6% (95% CI, 29.2%-32.0%). South America (3 studies, 5716 individuals) and North America (4 studies, 18,236 individuals) had the highest NAFLD prevalence at 35.7% (95% CI, 34.0%-37.5%) and 35.3% (95% CI, 25.4%-45.9%), respectively. From 1991 to 2019, trend analysis showed NAFLD increased from 21.9% to 37.3% (yearly increase of 0.7%, P < .0001), with South America showing the most rapid change of 2.7% per year, followed by Europe at 1.1%.

CONCLUSIONS

Despite regional variation, the global prevalence of NAFLD is increasing overall. Policy makers must work toward reversing the current trends by increasing awareness of NAFLD and promoting healthy lifestyle environments.

A Meta-Analysis on the Global Prevalence, Risk factors and Screening of Coronary Heart Disease in Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS

Cardiovascular disease remains the leading cause of death in patients with nonalcoholic fatty liver disease (NAFLD). Studies examining the association of coronary heart disease (CHD) and NAFLD are cofounded by various cardiometabolic factors, particularly diabetes and body mass index. Hence, we seek to explore such association by investigating the global prevalence, independent risk factors, and influence of steatosis grade on manifestation of CHD among patients with NAFLD.

METHODS

Two databases, Embase and Medline, were utilized to search for articles relating to NAFLD and CHD. Data including, but not limited to, continent, diagnostic methods, baseline characteristics, prevalence of CHD, CHD severity, NAFLD severity, and risk factors were extracted.

RESULTS

Of the 38 articles included, 14 reported prevalence of clinical coronary artery disease (CAD) and 24 subclinical CAD. The pooled prevalence of CHD was 44.6% (95% confidence interval [CI], 36.0%-53.6%) among 67,070 patients with NAFLD with an odds ratio of 1.33 (95% CI, 1.21%-1.45%; P &lt; .0001). The prevalence of CHD was higher in patients with moderate to severe steatosis (37.5%; 95% CI, 15.0%-67.2%) than those with mild steatosis (29.6%; 95% CI, 13.1%-54.0%). The pooled prevalence of subclinical and clinical CAD was 38.7% (95% CI, 29.8%-48.5%) and 55.4% (95% CI, 39.6%-70.1%), respectively.

CONCLUSION

Steatosis was found to be related with CHD involvement, with moderate to severe steatosis related to clinical CAD. Early screening and prompt intervention for CHD in NAFLD are warranted for holistic care in NAFLD.

Low Accuracy of FIB-4 and NAFLD Fibrosis Scores for Screening for Liver Fibrosis in the Population

BACKGROUND & AIMS

Fibrosis-4 (FIB-4) and the nonalcoholic fatty liver disease fibrosis score (NFS) are the 2 most popular noninvasive blood-based serum tests proposed for widespread fibrosis screening. We therefore aimed to describe the accuracy of FIB-4 and NFS to detect elevated liver stiffness as an indicator of hepatic fibrosis in low-prevalence populations.

METHODS

This study included a total of 5129 patients with concomitant measurement of FIB-4, NFS, and liver stiffness measurement (LSM) by Fibroscan (Echosens, France) from 5 independent population-based cohorts from Spain, Hong Kong, Denmark, England, and France; 3979 participants from the general population and 1150 from at-risk cohorts due to alcohol, diabetes, or obesity. We correlated LSM with FIB-4 and NFS, and calculated pre- and post-test predictive values of FIB-4 and NFS to detect elevated LSM at 8 kPa and 12 kPa cutoffs. The mean age was 53 ± 12 years, the mean body mass index was 27 ± 5 kg/m², and 2439 (57%) were women. One in 10 patients (552; 11%) had liver stiffness ≥8 kPa, but 239 of those (43%) had a normal FIB-4, and 171 (31%) had normal NFS. The proportion of false-negatives was higher in at-risk patients than the general population. FIB-4 was false-negative in 11% of diabetic subjects, compared with 2.5% false-negatives with NFS. Waist circumference outperformed FIB-4 and NFS for detecting LSM ≥8 kPa in the general population. Almost one-third (28%-29%) of elevated FIB-4/NFS were false-positive in both the general population and at-risk cohorts.

CONCLUSIONS

FIB-4 and NFS are suboptimal for screening purposes due to a high risk of overdiagnosis and a non-negligible percentage of false-negatives, especially in patients with risk factors for chronic liver disease. Waist circumference emerged as a potential first step to identify patients at risk for liver fibrosis in the general population.

Metabolic Dysfunction-Associated Fatty Liver Disease and Subsequent Development of Adverse Pregnancy Outcomes

BACKGROUND & AIMS

Recently, metabolic dysfunction-associated fatty liver disease (MAFLD), rather than nonalcoholic fatty liver disease (NAFLD), was proposed to better describe liver disease associated with metabolic dysfunction (MD). In this study, we attempted to investigate the impact of MAFLD on pregnancy complications.

METHODS

The current study is a secondary analysis of a multicenter prospective cohort designed to examine the risk of NAFLD during pregnancy. In the first trimester, enrolled pregnant women were evaluated for hepatic steatosis by liver ultrasonography, and blood samples were collected for biochemical measurements. The study population was divided into 3 groups: no NAFLD, hepatic steatosis but without metabolic dysfunction (non-MD NAFLD), and MAFLD. The primary outcome was the subsequent development of adverse pregnancy outcomes, including gestational diabetes mellitus, pregnancy-associated hypertension, preterm birth, and fetal growth abnormalities.

RESULTS

The study population consisted of 1744 pregnant women, including 1523 with no NAFLD, 43 with non-MD NAFLD, and 178 with MAFLD. The risk of subsequent development of adverse pregnancy outcomes was higher in MAFLD than in non-MD NAFLD (adjusted odds ratio, 4.03; 95% CI, 1.68-9.67), whereas the risk was not significantly different between no NAFLD and non-MD NAFLD. Among women with no NAFLD, the presence of MD increased the risk of adverse pregnancy outcomes. However, women with MAFLD were at higher risk for adverse pregnancy outcomes than women with no NAFLD without MD or those with no NAFLD with MD.

CONCLUSIONS

In pregnant women, MAFLD may be associated with an increased risk of subsequent adverse pregnancy outcomes.

Trends in Etiology-based Mortality From Chronic Liver Disease Before and During COVID-19 Pandemic in the United States

BACKGROUND & AIMS

During the global coronavirus disease 2019 (COVID-19) pandemic, patients with pre-existing chronic liver disease may represent a vulnerable population. We studied the etiology-based temporal trends in mortality of chronic liver disease and the underlying cause of death in the United States before and during the COVID-19 pandemic.

METHODS

Population-based analyses were performed on United States national mortality records (2017-2020). Temporal trends in quarterly age-standardized mortality were obtained by joinpoint analysis with estimates of quarterly percentage change (QPC).

RESULTS

Quarterly age-standardized all-cause mortality due to alcohol-related liver disease (ALD) initially increased at a quarterly rate of 1.1% before the COVID-19 pandemic, followed by a sharp increase during the COVID-19 pandemic at a quarterly rate of 11.2%. Likewise, steady increase in mortality of nonalcoholic fatty liver disease before the COVID-19 pandemic (QPC, 1.9%) accelerated during the COVID-19 pandemic (QPC, 6.6%). Although ALD-related mortality increased steeply compared with viral hepatitis-related mortality during the COVID-19 pandemic, the proportion of mortality due to COVID-19 among individuals with ALD was the lowest at 2.5%; more than 50% lower than viral hepatitis. The significant decline in all-cause mortality due to viral hepatitis before the COVID-19 pandemic plateaued during the COVID-19 pandemic due to increase in COVID-19-related mortality in individuals with viral hepatitis. Mortality due to cirrhosis increased markedly during the COVID-19 pandemic, mainly attributable to ALD.

CONCLUSION

All-cause mortality for ALD and nonalcoholic fatty liver disease rapidly accelerated during the COVID-19 pandemic compared with the pre-COVID-19 era. There has been a significant decline in viral hepatitis; however, a significant increase in COVID-related death in this population.

Liver Stiffness on Magnetic Resonance Elastography and the MEFIB Index and Liver-Related Outcomes in Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis of Individual Participants

BACKGROUND & AIMS

Magnetic resonance elastography (MRE) is an accurate biomarker of liver fibrosis; however, limited data characterize its association with clinical outcomes. We conducted an individual participant data pooled meta-analysis on patients with nonalcoholic fatty liver disease to evaluate the association between liver stiffness on MRE and liver-related outcomes.

METHODS

A systematic search identified 6 cohorts of adults with nonalcoholic fatty liver disease who underwent a baseline MRE and were followed for hepatic decompensation, hepatocellular carcinoma, and death. Cox and logistic regression were used to assess the association between liver stiffness on MRE and liver-related outcomes, including a composite primary outcome defined as varices needing treatment, ascites, and hepatic encephalopathy.

RESULTS

This individual participant data pooled meta-analysis included 2018 patients (53% women) with a mean (± standard deviation) age of 57.8 (±14) years and MRE at baseline of 4.15 (±2.19) kPa, respectively. Among 1707 patients with available longitudinal data with a median (interquartile range) of 3 (4.2) years of follow-up, the hazard ratio for the primary outcome for MRE of 5 to 8 kPa was 11.0 (95% confidence interval [CI]: 7.03-17.1, P < .001) and for ≥ 8 kPa was 15.9 (95% CI: 9.32-27.2, P < .001), compared with those with MRE <5 kPa. The MEFIB index (defined as positive when MRE ≥3.3 kPa and Fibrosis-4 ≥1.6) had a robust association with the primary outcome with a hazard ratio of 20.6 (95% CI: 10.4-40.8, P < .001) and a negative MEFIB had a high negative predictive value for the primary outcome, 99.1% at 5 years. The 3-year risk of incident hepatocellular carcinoma was 0.35% for MRE <5 kPa, 5.25% for 5 to 8 kPa, and 5.66% for MRE ≥8 kPa, respectively.

CONCLUSION

Liver stiffness assessed by MRE is associated with liver-related events, and the combination of MRE and Fibrosis-4 has excellent negative predictive value for hepatic decompensation. These data have important implications for clinical practice.

Nonalcoholic Fatty Liver Disease Without Metabolic-associated Fatty Liver Disease and the Risk of Metabolic Syndrome

BACKGROUND & AIMS

Metabolic (dysfunction)-associated fatty liver disease (MAFLD) was proposed to replace nonalcoholic fatty liver disease (NAFLD). Some people fulfill diagnostic criteria of NAFLD but not MAFLD (NAFLD without MAFLD), but the clinical implications of NAFLD in these subjects is unknown.

METHODS

We followed cohort of 12,197 men and women 20 years of age or older without metabolic dysfunction (defined by MAFLD criteria), heavy alcohol use, chronic viral hepatitis, liver cirrhosis, or malignancy for their risk of incident metabolic syndrome defined by Adult Treatment Panel III criteria.

RESULTS

By design, none of the study participants had MAFLD at baseline. The prevalence of NAFLD among participants without metabolic dysfunction meeting MAFLD criteria and without significant alcohol intake was 7.6%. During 74,508 person-years of follow-up, 2179 participants developed metabolic syndrome. The fully adjusted hazard ratio for metabolic syndrome comparing participants with NAFLD to those without it was 1.61 (95% confidence interval, 1.42-1.83). The increased risk of incident metabolic syndrome associated with NAFLD persisted for all studied subgroups, and the association was stronger for those with increased waist circumference (P for interaction = .029) and those without elevated triglycerides levels (P for interaction = .047).

CONCLUSION

In this large cohort, participants with NAFLD without MAFLD were at higher risk of developing metabolic syndrome compared to participants with no NAFLD and no MAFLD. Using MAFLD criteria may miss opportunities for early intervention in these subjects.

Serum HBcrAg and Hepatocellular Carcinoma in a Taiwanese Population Seronegative for HBsAg and Anti-HCV

BACKGROUND & AIMS

Hepatitis B core-related antigen (HBcrAg) is a surrogate seromarker of intrahepatic hepatitis B virus covalently closed circular DNA quantity and activity and a predictor of hepatocellular carcinoma (HCC) in chronic hepatitis B patients. We assess association between HBcrAg and HCC in individuals seronegative for hepatitis B surface antigen and anti-hepatitis C virus (NBNC) in Taiwan.

METHODS

A total of 129 newly developed HCC cases and 520 frequency-matched non-HCC controls were drawn from the REVEAL-NBNC cohort. Serum HBcrAg and other risk factors measured at recruitment were compared between cases and controls. Regression analysis was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

The proportion of baseline HBcrAg positivity (≥1000 U/mL) was significantly higher in HCC cases than in controls (12.4% vs 1.4%, P < .001). In multivariate analysis, HBcrAg positivity was associated with significantly higher risk of HCC (adjusted OR [95% CI]: 9.3 [3.3-26.4]; P < .001]. The HCC population attributable to HBcrAg positivity was 11.1% (95% CI: 9.7%-12.5%).

CONCLUSIONS

Seropositivity of HBcrAg might identify a subset of the NBNC population at higher risk of HCC in hepatitis B virus endemic areas.

Cell-specific Deletion of NLRP3 Inflammasome Identifies Myeloid Cells as Key Drivers of Liver Inflammation and Fibrosis in Murine Steatohepatitis

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease worldwide. The NLRP3 inflammasome, a platform for caspase-1 activation and release of interleukin 1β, is increasingly recognized in the induction of inflammation and liver fibrosis during NAFLD. However, the cell-specific contribution of NLRP3 inflammasome activation in NAFLD remains unknown.

METHODS

To investigate the role of NLRP3 inflammasome activation in hepatocytes, hepatic stellate cells (HSCs) and myeloid cells, a conditional Nlrp3 knock-out mouse was generated and bred to cell-specific Cre mice. Both acute and chronic liver injury models were used: lipopolysaccharide/adenosine-triphosphate to induce in vivo NLRP3 activation, choline-deficient, L-amino acid-defined high-fat diet, and Western-type diet to induce fibrotic nonalcoholic steatohepatitis (NASH). In vitro co-culture studies were performed to dissect the crosstalk between myeloid cells and HSCs.

RESULTS

Myeloid-specific deletion of Nlrp3 blunted the systemic and hepatic increase in interleukin 1β induced by lipopolysaccharide/adenosine-triphosphate injection. In the choline-deficient, L-amino acid-defined high-fat diet model of fibrotic NASH, myeloid-specific Nlrp3 knock-out but not hepatocyte- or HSC-specific knock-out mice showed significant reduction in inflammation independent of steatosis development. Moreover, myeloid-specific Nlrp3 knock-out mice showed ameliorated liver fibrosis and decreased HSC activation. These results were validated in the Western-type diet model. In vitro co-cultured studies with human cell lines demonstrated that HSC can be activated by inflammasome stimulation in monocytes, and this effect was significantly reduced if NLRP3 was downregulated in monocytes.

CONCLUSIONS

The study provides new insights in the cell-specific role of NLRP3 in liver inflammation and fibrosis. NLRP3 inflammasome activation in myeloid cells was identified as crucial for the progression of NAFLD to fibrotic NASH. These results may have implications for the development of cell-specific strategies for modulation of NLRP3 activation for treatment of fibrotic NASH.

Mendelian Randomization Analysis Reveals No Causal Relationship Between Nonalcoholic Fatty Liver Disease and Severe COVID-19

BACKGROUND & AIMS

The coronavirus disease 2019 (COVID-19) pandemic has witnessed more than 4.5 million deaths as of the time of writing. Whether nonalcoholic fatty liver disease (NAFLD) increases the risk for severe COVID-19 remains unclear. We sought to address this question using 2-sample Mendelian randomization (TSMR) analysis approaches in large cohorts.

METHODS

We performed large-scale TSMR analyses to examine whether there is a causal relationship between NAFLD, serum alanine aminotransferase, grade of steatosis, NAFLD Activity Score, or fibrosis stage and severe COVID-19. To maximize the power of this analysis, we performed a genome-wide meta-analysis to identify single nucleotide polymorphisms associated with NAFLD. We also examined the impact of 20 major comorbid factors of NAFLD on severe COVID-19.

RESULTS

Univariate analysis of the UK Biobank data demonstrated a significant association between NAFLD and severe COVID-19 (odds ratio [OR], 3.06; P = 1.07 × 10^-6). However, this association disappeared after demographic and comorbid factors were adjusted (OR, 1.57; P = .09). TSMR study indicated that NAFLD (OR, 0.97; P = .61), alanine aminotransferase level (OR, 1.03; P = .47), grade of steatosis (OR, 1.08; P = .41), NAFLD Activity Score (OR, 1.02; P = .39), and fibrosis stage (OR, 1.01; P = .87) were not associated with severe COVID-19. Among all NAFLD-related comorbid factors, body mass index (OR, 1.73; P = 7.65 × 10^-9), waist circumference (OR, 1.76; P = 2.58 × 10^-5), and hip circumference (OR, 1.33; P = 7.26 × 10^-3) were the only ones demonstrated a causal impact on severe COVID-19.

CONCLUSIONS

There is no evidence supporting that NAFLD is a causal risk factor for severe COVID-19. Previous observational associations between NAFLD and COVID-19 are likely attributed to the correlation between NAFLD and obesity.

Hepatosteatosis and Atherosclerotic Plaque at Coronary CT Angiography

Purpose

To assess the association between nonalcoholic fatty liver disease (NAFLD) and quantitative atherosclerotic plaque at CT.

Materials and Methods

In this post hoc analysis of the prospective Scottish Computed Tomography of the HEART trial (November 2010 to September 2014), hepatosteatosis and coronary artery calcium score were measured at noncontrast CT. Presence of stenoses, visually assessed high-risk plaque, and quantitative plaque burden were assessed at coronary CT angiography. Multivariable models were constructed to assess the impact of hepatosteatosis and cardiovascular risk factors on coronary artery disease.

Results

Images from 1726 participants (mean age, 58 years ± 9 [SD]; 974 men) were included. Participants with hepatosteatosis (155 of 1726, 9%) had a higher body mass index, more hypertension and diabetes mellitus, and higher cardiovascular risk scores (P < .001 for all) compared with those without hepatosteatosis. They had increased coronary artery calcium scores (median, 43 Agatston units [AU] [interquartile range, 0-273] vs 19 AU [0-225], P = .046), more nonobstructive disease (48% vs 37%, P = .02), and higher low-attenuation plaque burden (5.11% [0-7.16] vs 4.07% [0-6.84], P = .04). However, these associations were not independent of cardiovascular risk factors. Over a median of 4.7 years, there was no evidence of a difference in myocardial infarction between those with and without hepatosteatosis (1.9% vs 2.4%, P = .92).

Conclusion

Hepatosteatosis at CT was associated with an increased prevalence of coronary artery disease at CT, but this was not independent of the presence of cardiovascular risk factors.Keywords: CT, Cardiac, Nonalcoholic Fatty Liver Disease, Coronary Artery Disease, Hepatosteatosis, Plaque QuantificationClinical trial registration no. NCT01149590 Supplemental material is available for this article. © RSNA, 2022See also commentary by Abohashem and Blankstein in this issue.

Direct Comparison of US and MR Elastography for Staging Liver Fibrosis in Patients With Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS

As alternatives to the expensive liver biopsy for assessing liver fibrosis stage in patients with nonalcoholic fatty liver disease (NAFLD), we directly compared the diagnostic abilities of magnetic resonance elastography (MRE), vibration-controlled transient elastography (VCTE), and two-dimensional shear wave elastography (2D-SWE).

METHODS

Overall, 231 patients with biopsy-proven NAFLD were included. Intra- and inter-observer reproducibility was analyzed using intraclass correlation coefficient in a sub-group of 70 participants, in whom liver stiffness measurement (LSM) was performed by an elastography expert and an ultrasound expert who was an elastography trainee on the same day.

RESULTS

Valid LSMs were obtained for 227, 220, 204, and 201 patients using MRE, VCTE, 2D-SWE, and all three modalities combined, respectively. Although the area under the curve did not differ between the modalities for detecting stage ≥1, ≥2, and ≥3 liver fibrosis, it was higher for MRE than VCTE and 2D-SWE for stage 4. Sex was a significant predictor of discordance between VCTE and liver fibrosis stage. Skin-capsule distance and the ratio of the interquartile range of liver stiffness to the median were significantly associated with discordance between 2D-SWE and liver fibrosis stage. However, no factors were associated with discordance between MRE and liver fibrosis stage. Intra- and inter-observer reproducibility in detecting liver fibrosis was higher for MRE than VCTE and 2D-SWE.

CONCLUSIONS

MRE, VCTE, and 2D-SWE demonstrated excellent diagnostic accuracy in detecting liver fibrosis in patients with NAFLD. MRE demonstrated the highest diagnostic accuracy for stage 4 detection and intra- and inter-observer reproducibility. UMIN Clinical Trials Registry No. UMIN000031491.

A PNPLA3 Polymorphism Confers Lower Susceptibility to Incident Diabetes Mellitus in Subjects With Nonalcoholic Fatty Liver Disease

BACKGROUND AND AIMS

We investigated the association between the patatin-like phospholipase domain-containing-3 (PNPLA3) rs738409 genotype and the risk of diabetes mellitus (DM) using a biopsy-confirmed nonalcoholic fatty liver disease (NAFLD) cohort and a longitudinal observational cohort.

METHODS

Associations between genotypes and the prevalence of DM were evaluated with stratification according to the histological severity of NAFLD in the Boramae cohort (n = 706). A longitudinal cohort consisting of nondiabetic individuals with ≥2 health checkups was then selected to investigate the risk of incident DM according to the genotype (the GENIE cohort; n = 4998).

RESULTS

Among subjects with NAFLD in the Boramae cohort, the G allele was independently associated with a lower prevalence of DM in both NAFL (odds ratio [OR] per 1 allele, 0.66; 95% confidence interval [CI], 0.46-0.97) and nonalcoholic steatohepatitis (OR per 1 allele, 0.59; 95% CI, 0.38-0.92). This result was replicated in the longitudinal GENIE cohort. The G allele was associated with a lower risk of incident DM during the median follow-up of 60 months in subjects with NAFLD (hazard ratio, 0.65; 95% CI, 0.45-0.93). In contrast, G allele carriers without NAFLD showed higher odds for DM in the context of the Boramae cohort (OR, 2.44; 95% CI, 1.00-5.95).

CONCLUSIONS

These findings clarify conflicting results regarding the association between the PNPLA3 rs738409 genotype and the risk of DM, demonstrating a clear difference between subjects with and without NAFLD; this difference might be explained by the low metabolic risk in genetic NAFLD.

Weight Change and the Development of Nonalcoholic Fatty Liver Disease in Metabolically Healthy Overweight Individuals

INTRODUCTION

The study sought to investigate the effect of weight change on hepatic steatosis (HS) incidence with or without liver fibrosis in metabolically healthy overweight or obese individuals.

METHODS

A cohort of 14,779 metabolically healthy men and women who were overweight or obese (body mass index ≥23 kg/m²) and free from HS and an intermediate or high probability of fibrosis at baseline were followed for a median of 5.2 years. Metabolic health was defined as freedom from the components of metabolic syndrome and a homeostatic model assessment of insulin resistance <2.5. Weight changes were calculated as differences from baseline at the next subsequent visit. The outcome was HS incidence, with or without liver fibrosis, as assessed by liver ultrasound and 2 noninvasive fibrosis scores.

RESULTS

During 76,794.6 person-years of follow-up, 3539 cases of HS incidence were identified. The multivariable adjusted hazard ratios (95% confidence intervals) for HS incidence by weight change group, <-5.0%, -5.0%-1.0%, 1.0%-5.0%, and >5.0%, relative to the no weight change group (-0.9% to 0.9%) were 0.52 (0.44-0.60), 0.83 (0.75-0.92), 1.21 (1.10-1.33), and 1.51 (1.36-1.69), respectively. Clinically relevant weight loss of >5% was also associated with a lowered risk of HS with intermediate or high probability of advanced fibrosis. In mediation analyses, associations remained significant, although adjustment for metabolic risk factors was attenuating.

DISCUSSION

Clinically relevant weight loss was associated with a reduced risk of developing nonalcoholic fatty liver disease with or without intermediate or high probability of advanced fibrosis in metabolically healthy overweight or obese individuals.

Effect of Endoscopic Bariatric and Metabolic Therapies on Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Weight loss via lifestyle intervention remains the mainstay of treatment for nonalcoholic fatty liver disease (NAFLD). Endoscopic bariatric and metabolic therapies (EBMTs) have recently been developed as an alternative treatment option for obesity. This study aimed to assess the effect of FDA-approved EBMTs on NAFLD.

METHODS

We searched MEDLINE, EMBASE, Web of Science and Cochrane Central through December 2020 for studies that assessed changes in liver outcomes following EBMT. Primary Outcomes: Liver fibrosis.

SECONDARY OUTCOMES

Liver biochemistry, steatosis, NAFLD histological changes and insulin sensitivity. The Grading of Recommendations, Assessment, Development, and Evidence (GRADE) approach was conducted to assess quality of evidence.

RESULTS

Of 4994 potential studies, 18 studies with 863 patients were included. Average weight loss was 14.5% of initial weight at a 6-month follow-up. Primary outcomes: Following EBMT, liver fibrosis significantly reduced by standardized mean difference (SMD) of 0.7 (95% CI, 0.1, 1.3; P = .02).

SECONDARY OUTCOMES

There were significant improvements in other NAFLD surrogates including alanine aminotransferase (-9.0 U/L; 95% CI, -11.6, -6.4; P < .0001), hepatic steatosis (SMD: -1.0; 95% CI, -1.2, -0.8; P < .0001) and histologic NAFLD activity score (-2.50; 95% CI, -3.5, -1.5; P < .0001). Other metabolic parameters including insulin resistance and waist circumference also significantly improved. The overall quality of the evidence for primary outcomes was low to very low.

CONCLUSIONS

EBMTs appear effective at treating NAFLD with significant improvement in liver fibrosis. Given the worsening NAFLD pandemic and limitations of currently available therapies, EBMTs should be further investigated as a potential treatment option for this patient population.

Activation of Liver mTORC1 Protects Against NASH via Dual Regulation of VLDL-TAG Secretion and De Novo Lipogenesis

BACKGROUND & AIMS

Dysregulation of liver lipid metabolism is associated with the development and progression of nonalcoholic fatty liver disease, a spectrum of liver diseases including nonalcoholic steatohepatitis (NASH). In the liver, insulin controls lipid homeostasis by increasing triglyceride (TAG) synthesis, suppressing fatty acid oxidation, and enhancing TAG export via very low-density lipoproteins. Downstream of insulin signaling, the mechanistic target of rapamycin complex 1 (mTORC1), is a key regulator of lipid metabolism. Here, we define the role of hepatic mTORC1 activity in mouse models of NASH and investigate the mTORC1-dependent mechanisms responsible for protection against liver damage in NASH.

METHODS

Utilizing 2 rodent NASH-promoting diets, we demonstrate that hepatic mTORC1 activity was reduced in mice with NASH, whereas under conditions of insulin resistance and benign fatty liver, mTORC1 activity was elevated. To test the beneficial effects of hepatic mTORC1 activation in mouse models of NASH, we employed an acute, liver-specific knockout model of TSC1 (L-TSC-KO), a negative regulator of mTORC1.

RESULTS

L-TSC-KO mice are protected from and have improved markers of NASH including reduced steatosis, decreased circulating transaminases, and reduced expression of inflammation and fibrosis genes. Mechanistically, protection from hepatic inflammation and fibrosis by constitutive mTORC1 activity occurred via promotion of the phosphatidylcholine synthesizing enzyme, CCTα, and enhanced very low-density lipoprotein-triglyceride export. Additionally, activation of mTORC1 protected from hepatic steatosis via negative feedback of the mTORC2-AKT-FOXO-SREBP1c lipogenesis axis.

CONCLUSIONS

Collectively, this study identifies a protective role for liver mTORC1 signaling in the initiation and progression of NASH in mice via dual control of lipid export and synthesis.

Incidence of Hepatocellular Carcinoma in Patients With Nonalcoholic Fatty Liver Disease: A Systematic Review, Meta-analysis, and Meta-regression

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) may be a risk factor for hepatocellular carcinoma (HCC), but the extent of this association still needs to be addressed. Pooled incidence rates of HCC across the disease spectrum of NAFLD have never been estimated by meta-analysis.

METHODS

In this systematic review, we searched Web of Science, Embase, PubMed, and the Cochrane Library from January 1, 1950 through July 30, 2020. We included studies reporting on HCC incidence in patients with NAFLD. The main outcomes were pooled HCC incidences in patients with NAFLD at distinct severity stages. Summary estimates were calculated with random-effects models. Sensitivity analyses and meta-regression analyses were carried out to address heterogeneity.

RESULTS

We included 18 studies involving 470,404 patients. In patients with NAFLD at a stage earlier than cirrhosis, the incidence rate of HCC was 0.03 per 100 person-years (95% confidence interval [CI], 0.01-0.07; I² = 98%). In patients with cirrhosis, the incidence rate was 3.78 per 100 person-years (95% CI, 2.47-5.78; I² = 93%). Patients with cirrhosis undergoing regular screening for HCC had an incidence rate of 4.62 per 100 person-years (95% CI, 2.77-7.72; I² = 77%).

CONCLUSIONS

Patients with NAFLD-related cirrhosis have a risk of developing HCC similar to that reported for patients with cirrhosis from other etiologies. Evidence documenting the risk in patients with nonalcoholic steatohepatitis or simple steatosis is limited, but the incidence of HCC in these populations may lie below thresholds used to recommend a screening. Well-designed prospective studies in these subpopulations are needed. The protocol for this systematic review is registered in the Prospero database (registration number CRD42018092861).

Clinical Care Pathway for the Risk Stratification and Management of Patients With Nonalcoholic Fatty Liver Disease

Find AGA's NASH Clinical Care Pathway App for iOS and Android mobile devices at nash.gastro.org. Scan this QR code to be taken directly to the website.Nonalcoholic fatty liver disease (NAFLD) is becoming increasingly common, currently affecting approximately 37% of US adults. NAFLD is most often managed in primary care or endocrine clinics, where clinicians must determine which patients might benefit from secondary care to address hepatic manifestations, comorbid metabolic traits, and cardiovascular risks of the disease. Because NAFLD is largely asymptomatic, and because optimal timing of treatment depends on accurate staging of fibrosis risk, screening at the primary care level is critical, together with consistent, timely, evidence-based, widely accessible, and testable management processes. To achieve these goals, the American Gastroenterological Association assembled a multidisciplinary panel of experts to develop a Clinical Care Pathway providing explicit guidance on the screening, diagnosis, and treatment of NAFLD. This article describes the NAFLD Clinical Care Pathway they developed and provides a rationale supporting proposed steps to assist clinicians in diagnosing and managing NAFLD with clinically significant fibrosis (stage F2-F4) based on the best available evidence. This Pathway is intended to be applicable in any setting where care for patients with NAFLD is provided, including primary care, endocrine, obesity medicine, and gastroenterology practices.

Metabolic Dysfunction-Associated Fatty Liver Disease and Incident Cardiovascular Disease Risk: A Nationwide Cohort Study

BACKGROUND & AIMS

An international expert panel proposed a new definition for metabolic dysfunction-associated fatty liver disease (MAFLD) as a name change from nonalcoholic fatty liver disease (NAFLD). The clinical impact of this change on the assessment of cardiovascular disease (CVD) risk is yet unknown. We evaluated the prevalence of fatty liver disease (FLD) and the associated CVD risk using each of these definitions.

METHODS

From a nationwide health screening database, we included 9,584,399 participants (48.5% male) aged 40-64 years between 2009 and 2010. Participants were categorized by presence of NAFLD and MAFLD, separately, and by the combination of the 2 definitions-Neither-FLD, NAFLD-only, MAFLD-only, or Both-FLD. The primary outcome was a composite CVD event, including myocardial infarction, ischemic stroke, heart failure, or CVD-related death.

RESULTS

The prevalence of NAFLD and MAFLD was 28.0% and 37.3%, respectively. After excluding those with prior CVD, 8,962,813 participants were followed for a median of 10.1 years. NAFLD and MAFLD were each associated with significantly higher risk for CVD events. When the Neither-FLD group was the reference, multivariable-adjusted hazard ratios (95% confidence interval) for CVD events were 1.09 (1.03-1.15) in the NAFLD-only group, 1.43 (1.41-1.45) in the MAFLD-only group, and 1.56 (1.54-1.58) in the Both-FLD group.

CONCLUSIONS

A considerable proportion of middle-aged Korean adults have MAFLD without satisfying the former definition of NAFLD. The change from NAFLD to MAFLD criteria may identify a greater number of individuals with metabolically complicated fatty liver and increased risk for CVD.

Impact of the New Definition of Metabolic Associated Fatty Liver Disease on the Epidemiology of the Disease

BACKGROUND & AIMS

Recently, a group of hepatologists proposed to rename non-alcoholic fatty liver disease (NAFLD) as metabolic associated fatty liver disease (MAFLD) with modified diagnostic criteria. We aimed to study the impact of the new definition on the epidemiology of fatty liver disease.

METHODS

We randomly selected 1013 adults from the Hong Kong census database for clinical assessment, proton-magnetic resonance spectroscopy, and transient elastography. Five hundred sixty-five subjects without fatty liver at baseline underwent follow-up assessment. MAFLD was diagnosed as intrahepatic triglyceride content (IHTG) ≥5% and the presence of overweight/obesity, diabetes, or two other metabolic risk factors, with and without concomitant liver diseases. The diagnosis of NAFLD required the exclusion of concomitant liver diseases; metabolic factors were not considered.

RESULTS

The population prevalence of MAFLD and NAFLD was 25.9% (95% CI 23.2-28.7%) and 25.7% (95% CI 23.1-28.5%), respectively. Among 277 subjects with IHTG ≥5%, 247 (89.2%) fulfilled both the definitions of MAFLD and NAFLD. Fourteen subjects (5.1%) had IHTG ≥5% but did not meet the metabolic criteria of MAFLD. The incidence of MAFLD was 2.8 per 100 person-years at a median interval of 47 months (range 34-60 months). Among 78 subjects with incident NAFLD, 59 (75.6%) met the criteria of MAFLD; only one of the latter, a regular drinker, had liver stiffness ≥10 kPa.

CONCLUSIONS

The new definition of MAFLD does not significantly change the prevalence compared with NAFLD, but it may reduce the incidence by 25%. People with hepatic steatosis but not fulfilling the definition of MAFLD unlikely have significant liver disease.

Fatty Acids Activate the Transcriptional Coactivator YAP1 to Promote Liver Fibrosis via p38 Mitogen-Activated Protein Kinase

BACKGROUND & AIMS

Patients with simple steatosis (SS) and nonalcoholic steatohepatitis can develop progressive liver fibrosis, which is associated with liver-related mortality. The mechanisms contributing to liver fibrosis development in SS, however, are poorly understood. SS is characterized by hepatocellular free fatty acid (FFA) accumulation without lobular inflammation seen in nonalcoholic steatohepatitis. Because the Hippo signaling transcriptional coactivator YAP1 (YAP) has previously been linked with nonalcoholic fatty liver disease (NAFLD)-related fibrosis, we sought to explore how hepatocyte FFAs activate a YAP-mediated profibrogenic program.

METHODS

We analyzed RNA sequencing data from a GEO DataSet (accession: GSE162694) consisting of 143 patients with NAFLD. We also performed immunohistochemical, immunofluorescence, immunoblot, and quantitative reverse-transcription polymerase chain reaction analyses (qRT-PCR) in liver specimens from NAFLD subjects, from a murine dietary NAFLD model, and in FFA-treated hepatic spheroids and hepatocytes.

RESULTS

YAP-target gene expression correlated with increasing fibrosis stage in NAFLD patients and was associated with fibrosis in mice fed a NAFLD-inducing diet. Hepatocyte-specific YAP deletion in the murine NAFLD model attenuated diet-induced fibrosis, suggesting a causative role of YAP in NAFLD-related fibrosis. Likewise, in hepatic spheroids composed of Huh7 hepatoma cells and primary human hepatic stellate cells, Huh7 YAP silencing reduced FFA-induced fibrogenic gene expression. Notably, inhibition of p38 mitogen-activated protein kinase could block YAP activation in FFA-treated Huh7 cells.

CONCLUSIONS

These studies provide further evidence for the pathological role of YAP in NAFLD-associated fibrosis and that YAP activation in NAFLD may be driven by FFA-induced p38 MAPK activation.