Longitudinal Outcomes Associated With Metabolic Dysfunction-Associated Steatotic Liver Disease: A Meta-analysis of 129 Studies

Association between metabolic dysfunction-associated steatotic liver disease and myosteatosis measured by computed tomography

BACKGROUND

In 2023, the concept of metabolic dysfunction-associated steatotic liver disease (MASLD) was introduced as an alternative to non-alcoholic fatty liver disease (NAFLD). We aimed to assess the quantity and quality of skeletal muscle using each of these diagnostic classifications.

METHODS

This cross-sectional study included 18 154 participants (11 551 [63.6%] men and 6603 [36.4%] women, mean age 53.0 ± 8.8). The participants were classified into four categories: neither steatotic liver disease (SLD), NAFLD only, MASLD only or both SLDs. An appendicular skeletal muscle mass adjusted for body mass index of <0.789 for men and <0.512 for women was defined as sarcopenia. The total abdominal muscle area (TAMA) at the L3 vertebral level was segmented into normal-attenuation muscle area (NAMA), low-attenuation muscle area and intermuscular/intramuscular adipose tissue. Myosteatosis was defined by a T-score < -1.0 of the NAMA/TAMA index, which was calculated by dividing the NAMA by the TAMA and multiplying by 100.

RESULTS

Using subjects with neither SLD as a reference, the multivariable-adjusted odds ratios (ORs) for sarcopenia were significantly increased in those with MASLD, with adjusted ORs (95% confidence interval [CI]) of 2.62 (1.94-3.54) in the MASLD-only group and 2.33 (1.92-2.82) in the both SLDs group, while the association was insignificant in those with NAFLD only (adjusted OR [95% CI]: 2.16 [0.67-6.94]). The OR for myosteatosis was also elevated in the MASLD groups, with an OR (95% CI) of 1.75 (1.52-2.02) in subjects with MASLD only and 1.70 (1.57-1.84) in those with both SLDs, while it was slightly decreased in subjects with NAFLD only (0.52 [0.29-0.95]).

CONCLUSIONS

Employing the MASLD concept rather than that of the NAFLD proved to be more effective in distinguishing individuals with reduced muscle mass and compromised muscle quality.

Long-term clinical outcomes in steatotic liver disease and incidence of liver-related events, cardiovascular events and all-cause mortality

BACKGROUND

A multi-society consensus group proposed a new nomenclature for steatotic liver disease (SLD) including metabolic-dysfunction associated steatotic liver disease (MASLD), MASLD and increased alcohol intake (MetALD) and alcohol-associated liver disease (ALD). However, the risk of liver-related events, major adverse cardiovascular events (MACE) and all-cause mortality among various sub-groups is unknown.

AIMS

To evaluate the risk of liver-related events, MACE and death among patients with SLD.

METHODS

We conducted a nationwide, population-based study and enrolled 761,400 patients diagnosed with MASLD, MetALD or ALD. The primary endpoint was the occurrence of liver-related events, MACE and death in patients with MASLD, MetALD and ALD.

RESULTS

The cumulative incidence of liver-related events and death were highest in ALD, followed by MetALD and MASLD (p < 0.001 for both liver-related events and death), while the incidence of MACE was highest in MASLD, followed by MetALD and ALD (p < 0.001). Using MASLD as the reference and adjusting for age, sex, smoking, diabetes mellitus, dyslipidaemia and hypertension, the adjusted hazard ratios (95% confidence intervals) for liver-related events, MACE and death in MetALD were 1.42 (1.1-1.8), 0.68 (0.63-0.73) and 1.13 (0.98-1.3), respectively. In ALD, they were 3.42 (2.6-4.6), 0.58 (0.49-0.67) and 1.60 (1.3-2.0), respectively, for liver-related events, MACE and death.

CONCLUSIONS

The new consensus nomenclature can be used to stratify the risk of complications and prognosis. The nomenclature is beneficial for risk stratification and identifying new mechanisms for disease-specific therapeutic implications.

A high reticulocyte count is a risk factor for the onset of metabolic dysfunction-associated steatotic liver disease: Cross-sectional and prospective studies of data of 310,091 individuals from the UK Biobank

Background and Aims: Metabolic dysfunction-associated steatotic liver disease (MASLD) poses a considerable health risk. Nevertheless, its risk factors are not thoroughly comprehended, and the association between the reticulocyte count and MASLD remains uncertain. This study aimed to explore the relationship between reticulocyte count and MASLD. Methods: A total of 310,091 individuals from the UK Biobank were included in this cross-sectional study, and 7,316 individuals were included in this prospective study. The cross-sectional analysis categorized reticulocyte count into quartiles, considering the sample distribution. Logistic regression models examined the connection between reticulocyte count and MASLD. In the prospective analysis, Cox analysis was utilized to investigate the association. Results: Our study findings indicate a significant association between higher reticulocyte count and an elevated risk of MASLD in both the cross-sectional and prospective analyses. In the cross-sectional analysis, the adjusted odds ratios (ORs) of MASLD increased stepwise over reticulocyte count quartiles (quartile 2: OR 1.22, 95% CI 1.17-1.28, p < 0.001; quartile 3: OR 1.44; 95% CI 1.38-1.51, p < 0.001; quartile 4: OR 1.66, 95% CI 1.59-1.74, p < 0.001). The results of prospective analyses were similar. Conclusion: Increased reticulocyte count was independently associated with a higher risk of MASLD. This discovery offers new insights into the potential of reticulocytes as biomarkers for MASLD.

Metabolic-Dysfunction-Associated Steatotic Liver Disease (MASLD) after Liver Transplantation: A Narrative Review of an Emerging Issue

The development of steatotic liver disease after liver transplant (LT) is widely described, and epidemiological data have revealed an increased incidence in recent times. Its evolution runs from simple steatosis to steatohepatitis and, in a small proportion of patients, to significant fibrosis and cirrhosis. Apparently, post-LT steatotic disease has no impact on the recipient's overall survival; however, a higher cardiovascular and malignancy burden has been reported. Many donors' and recipients' risk factors have been associated with this occurrence, although the recipient-related ones seem of greater impact. Particularly, pre- and post-LT metabolic alterations are strictly associated with steatotic graft disease, sharing common pathophysiologic mechanisms that converge on insulin resistance. Other relevant risk factors include genetic variants, sex, age, baseline liver diseases, and immunosuppressive drugs. Diagnostic evaluation relies on liver biopsy, although non-invasive methods are being increasingly used to detect and monitor both steatosis and fibrosis stages. Management requires a multifaceted approach focusing on lifestyle modifications, the optimization of immunosuppressive therapy, and the management of metabolic complications. This review aims to synthesize the current knowledge of post-LT steatotic liver disease, focusing on the recent definition of metabolic-dysfunction-associated steatotic liver disease (MASLD) and its metabolic and multisystemic concerns.

Liver Cell Mitophagy in Metabolic Dysfunction-Associated Steatotic Liver Disease and Liver Fibrosis

Metabolic dysfunction-associated steatotic liver disease (MASLD) affects approximately one-third of the global population. MASLD and its advanced-stage liver fibrosis and cirrhosis are the leading causes of liver failure and liver-related death worldwide. Mitochondria are crucial organelles in liver cells for energy generation and the oxidative metabolism of fatty acids and carbohydrates. Recently, mitochondrial dysfunction in liver cells has been shown to play a vital role in the pathogenesis of MASLD and liver fibrosis. Mitophagy, a selective form of autophagy, removes and recycles impaired mitochondria. Although significant advances have been made in understanding mitophagy in liver diseases, adequate summaries concerning the contribution of liver cell mitophagy to MASLD and liver fibrosis are lacking. This review will clarify the mechanism of liver cell mitophagy in the development of MASLD and liver fibrosis, including in hepatocytes, macrophages, hepatic stellate cells, and liver sinusoidal endothelial cells. In addition, therapeutic strategies or compounds related to hepatic mitophagy are also summarized. In conclusion, mitophagy-related therapeutic strategies or compounds might be translational for the clinical treatment of MASLD and liver fibrosis.

Prognostic effect of triglyceride glucose-related parameters on all-cause and cardiovascular mortality in the United States adults with metabolic dysfunction-associated steatotic liver disease

BACKGROUNDS

Insulin resistance (IR) plays a vital role in the pathogenesis of the metabolic dysfunction-associated steatotic liver disease (MASLD). However, it remains unclear whether triglyceride-glucose (TyG) related parameters, which serve as useful biomarkers to assess IR, have prognostic effects on mortality outcomes of MASLD.

METHODS

Participants in the National Health and Nutrition Examination Survey (NHANES) database from 1999 to 2018 years were included. TyG and its related parameters [TyG-waist circumference (TyG-WC) and TyG-waist to height ratio (TyG-WHtR)] were calculated. Kaplan-Meier curves, Cox regression analysis, and restricted cubic splines (RCS) were conducted to evaluate the association between TyG-related indices with the all-cause and cardiovascular mortality of adults with MASLD. The concordance index (C-index) was used to evaluate the prediction accuracy of TyG-related indices.

RESULTS

A total of 8208 adults (4209 men and 3999 women, median age 49.00 years) with MASLD were included in this study. Multivariate-adjusted Cox regression analysis revealed that high quartile levels of TyG-related indices were significantly associated with the all-cause mortality of participants with MASLD [TyGadjusted hazard ratio (aHR) = 1.25, 95% confidence interval (CI) 1.05-1.50, P = 0.014; TyG-WCaHR for all-cause mortality = 1.28, 95% CI 1.07-1.52, P = 0.006; TyG-WHtRaHR for all-cause mortality = 1.50, 95% CI 1.25-1.80, P < 0.001; TyG-WCaHR for cardiovascular mortality = 1.81, 95% CI 1.28-2.55, P = 0.001; TyG-WHtRaHR for cardiovascular mortality = 2.22, 95% CI 1.55-3.17, P < 0.001]. The C-index of TyG-related indices for predicting all-cause mortality was 0.563 for the TyG index, 0.579 for the TyG-WC index, and 0.585 for the TyG-WHtR index, respectively. Regarding cardiovascular mortality, the C-index was 0.561 for the TyG index, 0.607 for the TyG-WC index, and 0.615 for the TyG-WHtR index, respectively. Nonlinear trends were observed between TyG and TyG-WC indices with all-cause mortality of MASLD (P < 0.001 and = 0.012, respectively). A non-linear relationship was observed between the TyG index and cardiovascular mortality of MASLD (P = 0.025). Subgroup analysis suggested that adults aged < 65 years old and those without comorbidities were more sensitive to the mortality prediction of TyG-related indices.

CONCLUSION

Findings of this study highlight the predictive value of TyG-related indices, especially the TyG-WHtR index, in the mortality outcomes of adults with MASLD. TyG-related indices would be surrogate biomarkers for the clinical management of MASLD.

Liver disease in patients with transfusion-dependent β-thalassemia: The emerging role of metabolism dysfunction-associated steatotic liver disease

In this Editorial, we highlight the possible role that metabolism dysfunction-associated steatotic liver disease (MASLD) may play in the future, regarding liver disease in patients with transfusion-dependent β-thalassemia (TDBT). MASLD is characterized by excessive accumulation of fat in the liver (hepatic steatosis), in the presence of cardiometabolic factors. There is a strong correlation between the occurrence of MASLD and insulin resistance, while its increased prevalence parallels the global epidemic of diabetes mellitus (DM) and obesity. Patients with TDBT need regular transfusions for life to ensure their survival. Through these transfusions, a large amount of iron is accumulated, which causes saturation of transferrin and leads to the circulation of free iron molecules, which cause damage to vital organs (primarily the liver and myocardium). Over the past, the main mechanisms for the development of liver disease in these patients have been the toxic effect of iron on the liver and chronic hepatitis C, for which modern and effective treatments have been found, resulting in successful treatment. Additional advances in the treatment and monitoring of these patients have led to a reduction in deaths, and an increase in their life expectancy. This increased survival makes them vulnerable to the onset of diseases, which until recently were mainly related to the non-thalassemic general population, such as obesity and DM. There is insufficient data in the literature regarding the prevalence of MASLD in this population or on the risk factors for its occurrence. However, it was recently shown by a study of 45 heavily transfused patients with beta-thalassemia (Padeniya et al, BJH), that the presence of steatosis is a factor influencing the value of liver elastography and thus liver fibrosis. These findings suggest that future research in the field of liver disease in patients with TDBT should be focused on the occurrence, the risk factors, and the effect of MASLD on these patients.

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.