Incidence of liver-related morbidity and mortality in a population cohort of non-alcoholic fatty liver disease

Unraveling the Association Between Cheese Consumption and Non-Alcoholic Fatty Liver Disease: Insights From a Two-Sample Mendelian Randomization Analysis

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease globally, and diet plays a crucial role in its progression. While dietary fats impact NAFLD, the specific effect of cheese consumption remains unclear. This study employs a two-sample Mendelian randomization (MR) approach to explore the causal relationship between cheese intake and NAFLD, liver fat content, and liver fat proportion. Using summary-level data from large genome-wide association studies, we applied a two-sample MR approach. Genetic variants linked to cheese consumption served as instrumental variables, selected under strict criteria, including genome-wide significance and exclusion of pleiotropy. Robustness was ensured through various MR methods, including Inverse Variance Weighted (IVW) and MR-Egger. MR analysis indicated that increased cheese consumption is negatively associated with NAFLD risk (OR = 0.589, 95% CI: 0.387-0.896, p = 0.014). This inverse relationship also extended to liver fat content (OR = 0.814, 95% CI: 0.689-0.960, p = 0.015) and liver fat proportion (OR = 0.830, 95% CI: 0.695-0.992, p = 0.04). No significant link was found between cheese intake and liver volume (OR = 0.976, 95% CI: 0.846-1.126, p = 0.737). Cheese intake may have a protective effect against NAFLD, potentially informing dietary management strategies. Further research is needed to confirm these findings across diverse populations.

Prognostic value of changes in vibration-controlled transient elastography parameters for liver, cardiovascular and mortality outcomes in individuals with type 2 diabetes and metabolic dysfunction-associated steatotic liver disease: The Rio de Janeiro type 2 diabetes cohort

BACKGROUND/AIMS

The prognostic importance of changes in vibration-controlled transient elastography (VCTE) parameters, liver stiffness measurement (LSM), and controlled attenuation parameter (CAP), in individuals with type 2 diabetes (T2D) and metabolic dysfunction-associated steatotic liver disease (MASLD) is unknown.

METHODS

A prospective cohort of 288 patients underwent 2 VCTE exams at least 2 years apart, and the relative percentage changes in LSM and CAP were calculated. Outcomes were the occurrence of any liver-related events (LREs), cardiovascular events (CVEs), and all-cause mortality. Multivariable Cox analyses, adjusted for liver and cardiometabolic factors, assessed associations between VCTE parameters changes, both as continuous and dichotomical variables (LSM increase >15% and CAP reduction >10%), and outcomes.

RESULTS

During a median follow-up of 6 years, there were 22 LREs, 28 CVEs, and 37 all-cause deaths. For LREs, baseline LSM was the strongest predictor, but LSM increases added further prognostic value (hazard ratio [HR]: 1.5 [1.0-2.1], 1-SD increment). For CVEs, both LSM increase (HR: 1.7 [1.3-2.3]) and CAP reduction (HR: 1.5 [1.0-2.3], 1-SD decrease) were significant predictors. For all-cause mortality, baseline CAP was a protective predictor. When classified into subgroups based on LSM and CAP changes, the subgroup with both increased LSM and reduced CAP had the highest risks for CVEs (HR:5.3 [1.4-19.6]) and all-cause mortality (HR: 3.4 [1.2-9.6]). The highest risk for LREs was observed in the subgroup with increased LSM without CAP reduction (HR: 3.5 [0.9-12.9]).

CONCLUSIONS

VCTE parameters changes, LSM increase and CAP reduction, provide prognostic information for adverse liver, cardiovascular, and mortality outcomes in individuals with T2D and MASLD.

Elevated GGT to HDL ratio as a marker for the risk of NAFLD and liver fibrosis

This study investigated the association between NAFLD and liver fibrosis and the ratio of gamma-glutamyl transferase to high-density lipoprotein cholesterol (GGT/HDL-C). In this cross-sectional study, we included 4764 subjects who participated in the National Health and Nutrition Examination Survey (NHANES) during 2017-2018. Adjusted multivariate logistic regression analysis was utilized to evaluate the relationships between GGT/HDL-C levels and NAFLD, fatty liver degree, and liver fibrosis. The non-linear link between NAFLD and the GGT/HDL-C ratio was examined using generalized additive models. There was a non-linear association between GGT/HDL-C and the risk of NAFLD, and all regression models demonstrated a strong relationship between GGT/HDL-C levels and the risk of liver fibrosis, the degree of hepatic steatosis, and the prevalence of NAFLD. Subgroup analyses revealed a significant correlation between the risk of NAFLD and the GGT/HDL-C ratio among Mexican Americans and young people in the 20-40 age range. The receiver operating characteristic (ROC) study showed that GGT/HDL-C was a more accurate predictor of NAFLD than GGT or HDL-C alone. In the U.S. population, an increased risk of NAFLD, the severity of hepatic steatosis, and the risk of liver fibrosis are independently correlated with an elevated GGT/HDL-C ratio.

The homeo-FIT-prolactin hypothesis: the role of prolactin in metabolic homeostasis - association or causality?

The homeo-fit-prolactin hypothesis proposes a causal metabolic role for prolactin with hypoprolactinemia and hyperprolactinemia leading to adverse metabolic alterations. However, prolactin within the normal range and up to four times the upper reference limit may be a consequence of metabolic adaption and have a positive metabolic role similar to increased insulin in pre-diabetes. As a consequence, drugs that would increase prolactin levels within this threshold may hold promising effects, particularly for patients with type 2 diabetes. A documented positive metabolic effect of prolactin just above the normal threshold would not just be of benefit to patients with diabetes but assist in the decision to treat mild hyperprolactinemia in other patient groups as well, e.g. drug-induced hyperprolactinemia or idiopathic hyperprolactinemia. Prolactin receptors are present in the pancreas, liver, and adipose tissue, and pre-clinical studies suggest a positive and causal effect of prolactin on the gluco-insulinemic profile and lipid metabolism. This narrative review examines the evidence for the homeo-fit-prolactin hypothesis with a particular focus on results from human studies.

Guideline for the Prevention and Treatment of Metabolic Dysfunction-associated Fatty Liver Disease (Version 2024)

With the rising epidemic of obesity, metabolic syndrome, and type 2 diabetes mellitus in China, metabolic dysfunction-associated non-alcoholic fatty liver disease has become the most prevalent chronic liver disease. This condition frequently occurs in Chinese patients with alcoholic liver disease and chronic hepatitis B. To address the impending public health crisis of non-alcoholic fatty liver disease and its underlying metabolic issues, the Chinese Society of Hepatology and the Chinese Medical Association convened a panel of clinical experts to revise and update the "Guideline of prevention and treatment of non-alcoholic fatty liver disease (2018, China)". The new edition, titled "Guideline for the prevention and treatment of metabolic dysfunction-associated fatty liver disease (Version 2024)", offers comprehensive recommendations on key clinical issues, including screening and monitoring, diagnosis and evaluation, treatment, and follow-up for metabolic dysfunction-associated fatty liver disease and metabolic dysfunction-associated steatotic liver disease. Metabolic dysfunction-associated fatty liver disease is now the preferred English term and is used interchangeably with metabolic dysfunction-associated steatotic liver disease. Additionally, the guideline emphasizes the importance of multidisciplinary collaboration among hepatologists and other specialists to manage cardiometabolic disorders and liver disease effectively.

Genetics of Metabolic Dysfunction-associated Steatotic Liver Disease: The State of the Art Update

Recent advances in the genetics of metabolic dysfunction-associated steatotic liver disease (MASLD) are gradually revealing the mechanisms underlying the heterogeneity of the disease and have shown promising results in patient stratification. Genetic characterization of the disease has been rapidly developed using genome-wide association studies, exome-wide association studies, phenome-wide association studies, and whole exome sequencing. These advances have been powered by the increase in computational power, the development of new analytical algorithms, including some based on artificial intelligence, and the recruitment of large and well-phenotyped cohorts. This review presents an update on genetic studies that emphasize new biological insights from next-generation sequencing approaches. Additionally, we discuss innovative methods for discovering new genetic loci for MASLD, including rare variants. To comprehensively manage MASLD, it is important to stratify risks. Therefore, we present an update on phenome-wide association study associations, including extreme phenotypes. Additionally, we discuss whether polygenic risk scores and targeted sequencing are ready for clinical use. With particular focus on precision medicine, we introduce concepts such as the interplay between genetics and the environment in modulating genetic risk with lifestyle or standard therapies. A special chapter is dedicated to gene-based therapeutics. The limitations of approved pharmacological approaches are discussed, and the potential of gene-related mechanisms in therapeutic development is reviewed, including the decision to perform genetic testing in patients with MASLD.

Socioeconomic factors associated with the presence of and outcomes in metabolic dysfunction-associated steatotic liver disease

BACKGROUND AND AIMS

The association between socioeconomic factors and disease severity is not well studied in people living with metabolic dysfunction-associated steatotic liver disease (MASLD). We thus examined if socioeconomic factors influence the presence of, or risk for future, major adverse liver outcomes (MALOs) in people living with MASLD.

METHODS

We conducted a register-based cohort study that included all individuals with a MASLD diagnosis between 1987 and 2020 in Sweden. Logistic and Cox regression were used to examine the association between socioeconomic factors (country of birth, educational level, and marital status) and the presence of MALOs before or upon MASLD diagnosis or during follow-up, respectively.

RESULTS

In total, 14 026 people living with MASLD were identified, among whom the median age was 55 years, 50% were male and 775 (5.5%) had MALOs before or upon diagnosis. The adjusted odds ratio (aOR) for pre-existing MALOs was higher in divorced (aOR = 1.29, 95% confidence interval [CI] = 1.06-1.57) compared to married individuals. The aOR for pre-existing MALOs was lower among those with >12 years of education (aOR = .76, 95% CI = .62-.93) compared to individuals with an education level of 10-12 years. During a 5.2-year median follow-up, several socioeconomic factors were associated with increased rates of developing MALOs in a crude model; however, none were independently associated with incident MALOs after adjustment for confounders.

CONCLUSIONS

Socioeconomic factors were associated with somewhat higher odds for prevalent, but not incident, MALOs in people living with MASLD, after adjustments. This suggests primarily that risk factors for fibrosis progression are differently distributed across socioeconomic subgroups.

ALT levels, alcohol use, and metabolic risk factors have prognostic relevance for liver-related outcomes in the general population

Background & Aims

A new nomenclature and subclassification for steatotic liver disease (SLD) was recently introduced. We validated the prognostic value of SLD subclasses in a Finnish population-based cohort and explored the impact of metabolic risk factors and alcohol consumption on liver-related outcomes and death.

Methods

The study included 23,910 individuals (47% men, mean age 50.5 ± 14.0 years, BMI 27.0 ± 4.7 kg/m2) from the FINRISK and Health 2000 health examination surveys with healthcare registry linkage for severe liver-related outcomes and deaths. SLD was identified by alanine aminotransferase (ALT) levels >20 U/L in women and >30 U/L in men (primary analysis) or fatty liver index (FLI) ≥60 (sensitivity analysis).

Results

The prevalence of ALT-defined SLD was 43% (n = 10,380), with subclass rates of 34.5% for metabolic dysfunction-associated steatotic liver disease (MASLD), 4.2% for coexistent MASLD and alcohol-related liver disease (ALD) (i.e., MetALD), and 1.8% for ALD. During a median 13.3-year follow-up, we observed 129 liver-related events. MetALD and ALD increased the age- and sex-adjusted liver-related outcome risk by fourfold (HR 3.83, 95% CI 2.51-5.84, p <0.001) and eightfold (HR 7.90, 95% CI 5.16-12.30, p <0.001), respectively, compared with patients with MASLD. ALD was also associated with the highest risk for non-liver mortality. Metabolic risk factors were present in 93% and 96% of individuals with ALT-defined SLD and ALD, respectively. Alcohol use amplified the risk of liver-related outcomes in individuals with MASLD. Sensitivity analyses by the FLI were similar.

Conclusion

SLD is a significant public health concern. Nearly all ALD cases exhibit metabolic risk factors. Among ALT-defined SLD subclasses, ALD presents the highest risk for both liver-related and non-liver-related outcomes. Alcohol use increases the risk of liver-related outcomes in individuals with MASLD.

Impact and implications

This study provides important information for physicians, researchers, and patients, demonstrating that the new classification of steatotic liver disease (SLD) has prognostic relevance at the population level. Evaluating the SLD subclass for a patient helps in understanding the magnitude of the risk for liver- and non-liver-related outcomes. In particular, the risks are highest in those with alcohol-related liver disease (ALD), but also increased in individuals with coexisting metabolic dysfunction-associated steatotic liver disease (MASLD) and ALD (MetALD) when compared with those with MASLD. However, alcohol use increased the risk of liver-related outcomes also in individuals with MASLD, highlighting the importance of evaluating alcohol use in every patient with SLD. Nearly all individuals with ALD have metabolic risk factors, and it is important to treat these factors to improve the survival of these patients.

ALT poorly predicts Nonalcoholic Fatty Liver Disease (NAFLD) and liver fibrosis as determined by vibration-controlled transient elastography in adult National Health and Nutrition Examination Survey 2017-2018

BACKGROUND

Non-alcoholic fatty liver disease is a growing problem in the United States, contributing to a range of liver disease as well as cardiovascular disease. ALT is the most widely used liver chemistry for NAFLD evaluation. We hypothesized that the normal range many laboratories use was too high, missing many patients with clinically important steatosis and/or fibrosis.

METHODS

This study utilized 2017-2018 NHANES data including 9254 participants. We compared four different upper limits of normal for ALT with specific measurements of steatosis and liver stiffness as determined by liver elastography with FibroScan®. Liver stiffness was further characterized as showing any fibrosis or advanced fibrosis. After exclusions, our final pool was 4184 for liver stiffness measurement and 4183 for steatosis grade as measured by Controlled Attenuation Parameter (CAP). Using these variables, we performed logistic regression between ALT and CAP, and ALT and fibrosis/advanced fibrosis, and did a Receiver Operating Characteristic curve.

RESULTS

Based on three of the most widely used cut off values for ALT, we found that ALT does not reliably rule out NAFLD in over 50% of cases. It also missed 45.9-64.2% of patients with liver fibrosis.

CONCLUSIONS

Our study revealed that ALT is an inaccurate marker for NAFLD as measured by FibroScan® with CAP greater than or equal to 300 dB/m. Accuracy improved specific risk factors were considered. These data also showed that ALT was a poor marker for liver fibrosis. We conclude that there is no single ALT level that accurately predicts hepatic steatosis or fibrosis.

Combined use of the ELF test and CLivD score improves prediction of liver-related outcomes in the general population

BACKGROUND AND AIMS

Effective and feasible population screening strategies are needed for the early detection of individuals at high risk of future severe liver-related outcomes. We evaluated the predictive performance of the combination of liver fibrosis assessment, phenotype profile, and genetic risk.

METHODS

Data from 5795 adults attending the Finnish Health 2000 Survey were linked with healthcare registers for liver-related outcomes (hospitalization, hepatocellular cancer, and death). Fibrosis was assessed using the enhanced liver fibrosis (ELF) test, phenotype profile by the chronic liver disease (CLivD) risk score, and genetic risk by a validated Polygenic Risk Score (PRS-5). Predictive performance was assessed by competing-risk analyses.

RESULTS

During a median 13-year follow-up, 64 liver-related outcome events were recorded. ELF, CLivD score, and PRS-5 were independently associated with liver-related outcomes. The absolute 10-year risk of liver-related outcomes at an ELF value of 11.3 ranged from 0.3% to 33% depending on the CLivD score. The CLivD score added 51% of new predictive information to the ELF test and improved areas under the curve (AUCs) from 0.91, 0.81, and 0.71 for ELF alone to 0.95, 0.85, and 0.80, respectively, for ELF combined with the CLivD score at 1, 5, and 10 years. The greatest improvement was for 10-year predictions (delta-AUC 0.097, p < .0001). Adding PRS-5 did not significantly increase predictive performance. Findings were consistent in individuals with obesity, diabetes, or alcohol risk use, and regardless of whether gamma-glutamyltransferase was used in the CLivD score.

CONCLUSION

A combination of ELF and CLivD score predicts liver-related outcomes significantly better than the ELF test alone.

Enhanced liver Fibrosis® test predicts liver-related outcomes in the general population

Background & Aims

The Enhanced Liver Fibrosis® (ELF) test exhibits good discriminative performance in detecting advanced liver fibrosis and in predicting liver-related outcomes in patients with specific liver diseases, but large population-based studies are missing. We analysed the predictive performance of the ELF test in a general population cohort.

Methods

Data were sourced from the Health 2000 study, a Finnish population-based health examination survey conducted in 2000-2001. Subjects with baseline liver disease were excluded. The ELF test was performed on blood samples collected at baseline. Data were linked with national healthcare registers for liver-related outcomes (hospitalisation, cancer, and death).

Results

The cohort comprised 6,040 individuals (mean age 52.7. 45.6% men) with 67 liver-related outcomes during a median 13.1-year follow-up. ELF predicted liver outcomes (unadjusted hazards ratio 2.70, 95% CI 2.16-3.38). with 5- and 10-year AUCs of 0.81 (95% CI 0.71-0.91) and 0.71 (95% CI 0.63-0.79) by competing-risk methodology. The 10-year risks for liver outcomes increased from 0.5% at ELF <9.8 to 7.1% at ELF ≥11.3, being higher among men than women at any given ELF level. Among individuals with body mass index ≥30 kg/m2, diabetes, or alanine aminotransferase >40 U/L. Five-year AUCs for ELF were 0.85, 0.87, and 0.88, respectively. The predictive ability of the ELF test decreased with time: the 10-year AUCs were 0.78, 0.69, and 0.82, respectively.

Conclusions

The ELF test shows good discriminative performance in predicting liver-related outcomes in a large general population cohort and appears particularly useful for predicting 5-year outcomes in persons with risk factors.

Impact and implications

The Enhanced Liver Fibrosis test exhibits good performance for predicting liver-related outcomes (hospitalisation, liver cancer, or liver-related death) in the general population, especially in those with risk factors.

Age and the relative importance of liver-related deaths in nonalcoholic fatty liver disease

BACKGROUND AND AIMS

It is unclear if the leading causes of death in patients with NAFLD differ by age. We aimed to investigate if the relative importance of liver-related deaths is lower and overshadowed by cardiovascular and cancer-related deaths in the elderly population.

APPROACH AND RESULTS

We conducted a territory-wide retrospective cohort study of adult patients with NAFLD between 2000 and 2021 in Hong Kong. The outcomes of interest were all-cause and cause-specific mortality. Age groups at death were studied at 10-year intervals. During 662,471 person-years of follow-up of 30,943 patients with NAFLD, there were 2097 deaths. The top three causes of death were pneumonia, extrahepatic cancer, and cardiovascular diseases. Liver disease was the sixth leading cause of death in patients aged 70-79 and 80-89 years, accounting for 5.1% and 5.9% of deaths, respectively, but only accounted for 3% or fewer of the deaths in the other age groups. Nonetheless, liver disease was the leading cause of death in patients with NAFLD-related cirrhosis, accounting for 36.8% of all deaths. The incidence of liver-related death was higher in men younger than age 70 but higher in women afterwards. The incidence of liver-related death in women increased from 0.62 to 7.14 per 10,000 person-years from age 60-69 to 70-79 years.

CONCLUSION

The relative importance of liver-related death increases with age in patients with NAFLD, especially among women. In patients with cirrhosis, liver disease is the leading cause of death.

Surveillance of the progression and assessment of treatment endpoints for nonalcoholic steatohepatitis

Nonalcoholic steatohepatitis (NASH) is an aggressive form of nonalcoholic fatty liver disease (NAFLD) characterized by steatosis-associated inflammation and liver injury. Without effective treatment or management, NASH can have life-threatening outcomes. Evaluation and identification of NASH patients at risk for adverse outcomes are therefore important. Key issues in screening NASH patients are the assessment of advanced fibrosis, differentiation of NASH from simple steatosis, and monitoring of dynamic changes during follow-up and treatment. Currently, NASH staging and evaluation of the effectiveness for drugs still rely on pathological diagnosis, despite sample error issues and the subjectivity associated with liver biopsy. Optimizing the pathological assessment of liver biopsy samples and developing noninvasive surrogate methods for accessible, accurate, and safe evaluation are therefore critical. Although noninvasive methods including elastography, serum soluble biomarkers, and combined models have been implemented in the last decade, noninvasive diagnostic measurements are not widely applied in clinical practice. More work remains to be done in establishing cost-effective strategies both for screening for at-risk NASH patients and identifying changes in disease severity. In this review, we summarize the current state of noninvasive methods for detecting steatosis, steatohepatitis, and fibrosis in patients with NASH, and discuss noninvasive assessments for screening at-risk patients with a focus on the characteristics that should be monitored at follow-up.

Association between perfluoroalkyl substances exposure and the prevalence of nonalcoholic fatty liver disease in the different sexes: a study from the National Health and Nutrition Examination Survey 2005-2018

There is evidence that perfluoroalkyl substances (PFASs) have effects on liver toxicity, and the effects may exhibit sex differences. Our study aims to explore the association between exposure to four PFASs (perfluorooctanoic acid, PFOA; perfluorooctane sulfonate, PFOS; perfluorohexane sulfonate, PFHxS; and perfluorononanoate, PFNA) and the risk of nonalcoholic fatty liver disease (NAFLD) in adults ≥ 20 years old in the US population. The data were based on the National Health and Nutrition Examination Survey (NHANES) 2005-2018. We used Poisson regression to explore the association between the four PFASs and NAFLD. We included 3464 participants; of these, 1200 (34.64%) individuals were defined as having NAFLD, and the prevalence of NAFLD was 39.52% in men and 30.40% in women. After Poisson regression, among the premenopausal and postmenopausal and total women, PFOA had a significantly positive association with NAFLD (p < 0.05). After principal component analysis, the "composite PFAS" was associated with NAFLD in postmenopausal and total women, and the RRs (95% CIs) were 1.306 (1.075, 1.586) and 1.161 (1.007, 1.339), respectively. In adults, we found that PFASs were associated with NAFLD, and the associations varied by sex, particularly for PFOA and PFNA, which had a positive association with NAFLD in women.

Alcohol consumption and metabolic syndrome: Clinical and epidemiological impact on liver disease

Alcohol use and metabolic syndrome are highly prevalent in the population and frequently co-exist. Both are implicated in a large range of health problems, including chronic liver disease, hepatocellular carcinoma, and liver-related outcomes (i.e. decompensation or liver transplantation). Studies have yielded mixed results regarding the effects of mild-moderate alcohol consumption on the risk of metabolic syndrome and fatty liver disease, possibly due to methodological differences. The few available prospective studies have indicated that mild-moderate alcohol use is associated with an increase in liver-related outcomes. This conclusion was substantiated by systems biology analyses suggesting that alcohol and metabolic syndrome may play a similar role in fatty liver disease, potentiating an already existing dysregulation of common vital homeostatic pathways. Alcohol and metabolic factors are independently and jointly associated with liver-related outcomes. Indeed, metabolic syndrome increases the risk of liver-related outcomes, regardless of alcohol intake. Moreover, the components of metabolic syndrome appear to have additive effects when it comes to the risk of liver-related outcomes. A number of population studies have implied that measures of central/abdominal obesity, such as the waist-to-hip ratio, can predict liver-related outcomes more accurately than BMI, including in individuals who consume harmful quantities of alcohol. Many studies even point to synergistic interactions between harmful alcohol use and many metabolic components. This accumulating evidence showing independent, combined, and modifying effects of alcohol and metabolic factors on the onset and progression of chronic liver disease highlights the multifactorial background of liver disease in the population. The available evidence suggests that more holistic approaches could be useful for risk prediction, diagnostics and treatment planning.

A potential link between plasma short‑chain fatty acids, TNF‑α level and disease progression in non‑alcoholic fatty liver disease: A retrospective study

The onset and progression of non-alcoholic fatty liver disease (NAFLD) remains unclear, but short-chain fatty acids (SCFAs) in circulation may participate in its pathogenesis by acting as inflammation inhibitors. The aim of this retrospective study was to investigate plasma concentrations of general SCFAs in healthy individuals and in patients with distinct stages of NAFLD. Three main SCFAs (including acetate, propionate and butyrate) were analyzed by gas chromatography. The plasma TNF-α concentration was measured by ELISA. One-way ANOVA, Spearman's correlation and Pearson's correlation analysis were performed to estimate the associations between SCFAs, TNF-α and disease progression. Multiple linear stepwise regression was computed to explore the predictor variables of TNF-α in circulation. A total of 71 patients with NAFLD [including 27 patients with NAFL, 20 patients with non-alcoholic steatohepatitis (NASH) and 24 patients with NAFLD-related cirrhosis (NAFLD-cirrhosis)] and 9 healthy control (HC) subjects were enrolled for analysis. Although not statistically significant, plasma SCFAs were elevated in patients with NAFL compared with HC subjects, whereas the vast majority of SCFAs were statistically reduced in patients with NASH or NAFLD-cirrhosis compared with patients with NAFL. Plasma SCFAs had no significant differences in NASH or NAFLD-cirrhosis patients compared with HC subjects. In addition, significant negative correlations were observed between TNF-α and SCFAs. The progression of NAFLD (β=0.849; P<0.001) and the decline of the total three SCFA concentrations (β=-0.189; P<0.001) were recognized as independent risk variables related to the elevated peripheral TNF-α in the multiple linear stepwise regression model. Plasma SCFA concentrations may alter with the development of NAFLD and may have a potential link to TNF-α and the progression of NAFLD, which may serve a protective role toward disease advancement. Further mechanistic studies, such as analysis of gastrointestinal microecology, signaling pathways and functions involved in TNF-α, need to be performed. Also, therapeutic supplementation of SCFAs for NASH and NAFLD-cirrhosis needs further research and verification.