The independent effect of exercise on biopsy-proven non-alcoholic fatty liver disease: A systematic review

Differential Exercise Requirements for Nonalcoholic Fatty Liver Disease Resolution Across Age Groups: A Longitudinal Study of Korean Military Officers

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a global health concern, and despite its high prevalence, lifestyle modifications such as exercise play a pivotal role in resolving this condition. This study aims to identify factors associated with NAFLD resolution, with a focus on the role of exercise, in different age groups.

METHODS

Longitudinal data from Korean military officers, during the period 2019-2021, were obtained from the National Health Information Database. NAFLD was defined as a hepatic steatosis index ≥36, and NAFLD resolution was defined as individuals achieving hepatic steatosis index <36 in the subsequent year of diagnosis. Information on alcohol consumption, exercise frequency, and family history of diabetes was collected through self-reported questionnaires.

RESULTS

The analysis included a total of 163,728 individuals, with a mean age of 36.87, predominantly male (91.62%). The prevalence of NAFLD was 27.04%. Favorable factors for NAFLD resolution encompassed moderate-intensity exercise for more than 180 minutes per week, vigorous-intensity exercise for more than 90 minutes per week, female sex, age, and resistance exercise for more than 3 days per week. Hypertension, family history of diabetes, and smoking were identified as factors against NAFLD resolution. The exercise requirements for NAFLD resolution varied among age groups, with those <30 years old requiring more than 180 minutes per week of moderate- or vigorous-intensity exercise and those >50 years old needing only 90 minutes per week of such exercise.

CONCLUSION

The exercise requirements for NAFLD resolution exhibit age-related differences. Individualized guidance for NAFLD management should consider these variations and be tailored to specific age groups.

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.

NAFLD Fibrosis Progression and Type 2 Diabetes: The Hepatic-Metabolic Interplay

The bidirectional relationship between type 2 diabetes and (non-alcoholic fatty liver disease) NAFLD is indicated by the higher prevalence and worse disease course of one condition in the presence of the other, but also by apparent beneficial effects observed in one, when the other is improved. This is partly explained by their belonging to a multisystemic disease that includes components of the metabolic syndrome and shared pathogenetic mechanisms. Throughout the progression of NAFLD to more advanced stages, complex systemic and local metabolic derangements are involved. During fibrogenesis, a significant metabolic reprogramming occurs in the hepatic stellate cells, hepatocytes, and immune cells, engaging carbohydrate and lipid pathways to support the high-energy-requiring processes. The natural history of NAFLD evolves in a variable and dynamic manner, probably due to the interaction of a variable number of modifiable (diet, physical exercise, microbiota composition, etc.) and non-modifiable (genetics, age, ethnicity, etc.) risk factors that may intervene concomitantly, or subsequently/intermittently in time. This may influence the risk (and rate) of fibrosis progression/regression. The recognition and control of the factors that determine a rapid progression of fibrosis (or its regression) are critical, as the fibrosis stages are associated with the risk of liver-related and all-cause mortality.

Higher oxidative balance scores are associated with lower nonalcoholic fatty liver disease and not with fibrosis in US adults

BACKGROUND AND AIMS

Little research have focused on the relationship between systemic oxidative stress status and NAFLD and fibrosis. The Oxidative Balance Score (OBS) is employed to evaluate whole-body lifestyle and diet exposures related to oxidative stress, with higher OBS scores implying exposure to more antioxidants. This study aimed to explore whether OBS is correlated with NAFLD and NAFLD-related fibrosis.

METHODS AND RESULTS

12,223 participants from NHANES 2003-2018 were enrolled in this study. NAFLD was defined as USFLI ≥30 and liver fibrosis was determined as FIB-4 ≥ 2.67. OBS was scored by 20 lifestyle and dietary factors. Weighted logistic regression and restricted cubic splines were used to assess the association between OBS and NAFLD and fibrosis. The prevalence of NAFLD was 29.67%. There was a significant negative correlation between OBS, dietary OBS, lifestyle OBS and NAFLD and no correlation with NAFLD-related fibrosis. Compared to the lowest quartile, the adjusted ORs for the highest quartile of OBS, lifestyle OBS, dietary OBS and NAFLD were 0.55(95%CI:0.35,0.85), 0.12(95%CI:0.08,0.16), 0.70(95%CI:0.52,0.94) respectively. In stratified analyses, lifestyle OBS was negatively associated with NAFLD across gender, dietary OBS was only negatively correlated with NAFLD in men, and any OBS was not observed to be relevant to NAFLD-related fibrosis.

CONCLUSIONS

OBS was negatively associated with NAFLD, but not with NAFLD-related fibrosis. The findings underline the significance of adhering to an antioxidant lifestyle and diet, which can help prevent NAFLD but seems to be ineffective in preventing fibrosis in individuals with NAFLD.