Long-Term Outcomes of Nonalcoholic Fatty Liver Disease

MASLD/MetALD and mortality in individuals with any cardio-metabolic risk factor: A population-based study with 26.7 years of follow-up

BACKGROUND AND AIMS

A new term, metabolic dysfunction-associated steatotic liver disease (MASLD), has been proposed by a multi-society expert panel. However, it remains unclear whether hepatic steatosis per se in MASLD contributes to an increased risk of mortality in individuals with any cardio-metabolic risk factor (CMRF), which is also a significant risk factor for increased mortality. This study aimed to compare all-cause and cause-specific mortality between the "MASLD/MetALD" and "no steatotic liver disease (SLD)" groups in individuals with any CMRF.

APPROACH AND RESULTS

A population-based cohort study was conducted using 10,750 participants of the Third National Health and Nutrition Examination Survey. All-cause and cause-specific (cardiovascular, cancer, diabetes, and liver) mortality risks were compared between the "MASLD," "MetALD," and "no SLD" groups using the Cox proportional hazards model with complex survey design weights, adjusted for confounders. Over 26 years, the "MASLD" group did not show significantly increased all-cause (adjusted HR 1.04[95% CI: 0.95-1.14], p = 0.413), cardiovascular (0.88 [0.75-1.04], p = 0.139), or cancer (1.06[0.84-1.33], p = 0.635) mortality risk compared to the "no SLD" group in individuals with any CMRF. The MetALD group was associated with increased all-cause (1.41 [1.05-1.89], p = 0.022), cancer (2.35 [1.33-4.16], p = 0.004), and liver (15.04 [2.96-76.35], p = 0.002) mortality risk compared with the no SLD group. This trend was more pronounced in the MetALD group with advanced fibrosis assessed by Fibrosis-4 (FIB-4).

CONCLUSIONS

In individuals with CMRF, the presence of steatotic liver disease (MASLD) alone did not increase the risk of mortality, except in cases with more alcohol consumption (MetALD). Therefore controlling metabolic risk factors and reducing alcohol consumption in people with MASLD or MetALD will be crucial steps to improve long-term health outcomes.

Tailored Model of Care for Patients with Metabolic Dysfunction-Associated Steatotic Liver Disease

Metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as nonalcoholic fatty liver disease (NAFLD), is increasing globally, creating a growing public health concern. However, this disease is often not diagnosed, and accurate data on its epidemiology are limited in many geographical regions, making it challenging to provide proper care and implement effective national plans. To combat the increasing disease burden, screening and diagnosis must reach a significant number of high-risk subjects. Addressing MASLD as a health care challenge requires a multidisciplinary approach involving prevention, diagnosis, treatment, and care, with collaboration between multiple stakeholders in the health care system. This approach must be guided by national and global strategies, to be combined with efficient models of care developed through a bottom-up process. This review article highlights the pillars of the MASLD model of care (MoC), including screening, risk stratification, and establishing a clinical care pathway for management, in addition to discussing the impact of nomenclature change on the proposed MoC.

Causes and risk profiles of mortality among individuals with nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the United States and worldwide. Though nonalcoholic fatty liver per se may not be independently associated with an increased risk for all-cause mortality, it is associated with a number of harmful metabolic risk factors, such as type 2 diabetes mellitus, hyperlipidemia, obesity, a sedentary lifestyle, and an unhealthy diet. The fibrosis stage is a predictor of all-cause mortality in NAFLD. Mortality in individuals with NAFLD has been steadily increasing, and the most common cause-specific mortality for NAFLD is cardiovascular disease, followed by extra-hepatic cancer, liver-related mortality, and diabetes. High-risk profiles for mortality in NAFLD include PNPLA3 I148M polymorphism, low thyroid function and hypothyroidism, and sarcopenia. Achieving weight loss through adherence to a high-quality diet and sufficient physical activity is the most important predictor of improvement in NAFLD severity and the benefit of survival. Given the increasing health burden of NAFLD, future studies with more long-term mortality data may demonstrate an independent association between NAFLD and mortality.

Hepatic fibrosis is associated with an increased rate of decline in bone mineral density in men with nonalcoholic fatty liver disease

BACKGROUND

There is still controversy about the association between nonalcoholic fatty liver disease (NAFLD) and bone mineral density (BMD). The aim of this study was to clarify the association between NAFLD and the decline in BMD in healthcare examinees.

METHODS

Participants who underwent regular health check-ups with BMD and hepatic ultrasonography from 2006 to 2015 with more than one follow-up until 2020 were included. Propensity score matching was performed between the NAFLD group and the control group, and mixed linear regression models were used for the longitudinal analysis.

RESULTS

Of 2623 eligible participants (mean age 58.7 ± 7.3 years; males 31.3%), 888 (33.9%) had NAFLD. At baseline, the NAFLD group had a higher total hip BMD than the non-NAFLD group in men (0.988 vs. 1.015 g/cm², p = 0.007); however, there was no difference in baseline BMD in women (p = 0.253). In longitudinal analysis during a follow-up period of 7.1 years, there was no significant difference in the BMD decline rate between the two groups in the PS-matched cohort (p = 0.816 in men and p = 0.827 in women). However, among men with NAFLD, those with a high and intermediate probability of advanced fibrosis by the FIB-4 showed a significantly increased rate of decline in total hip BMD compared to those with low scores (0.01 vs. - 0.19% change/year, p = 0.011).

CONCLUSIONS

NAFLD was not associated with the total hip BMD decline rate. However, hepatic fibrosis was significantly associated with an increased rate of decline in total hip BMD in men with NAFLD.

CLINICAL TRIAL REGISTRATION

This study is a retrospective observational study and is not a drug trial. There was no need for clinical trial registration.

Recent Epidemiology of Nonalcoholic Fatty Liver Disease

The ongoing obesity epidemic and the increasing recognition of metabolic syndrome have contributed to the growing prevalence of nonalcoholic fatty liver disease (NAFLD), the most common form of liver disease worldwide. It is imperative to understand the incidence and prevalence of NAFLD as it is associated with a profound economic burden of hospitalizations, including the shifting trends in liver transplantation. The long-term cumulative healthcare cost of NAFLD patients has been shown to be 80% higher than that of non-NAFLD patients. We explore diagnostic challenges in identifying those with NAFLD who have a higher predilection to progress to end-stage liver disease. We aim to assess all-cause and cause-specific mortality as it relates to NAFLD.

Freeze-dried Si-Ni-San powder can ameliorate high fat diet-induced non-alcoholic fatty liver disease

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disease worldwide. However, to date, there is no ideal therapy for this disease.

AIM

To study the effects of Si-Ni-San freeze-dried powder on high fat diet-induced NAFLD in mice.

METHODS

Twenty-four male C57BL/6 mice were randomized into three groups of eight. The control group (CON) was allowed ad libitum access to a normal chow diet. The high fat diet group (FAT) and Si-Ni-San group (SNS) were allowed ad libitum access to a high fat diet. The SNS group was intragastrically administered Si-Ni-San freeze-dried powder (5.0 g/kg) once daily, and the CON and FAT groups were intragastrically administered distilled water. After 12 wk, body weight, liver index, visceral fat index, serum alanine aminotransferase (ALT), portal lipopoly-saccharide (LPS), liver tumor necrosis factor (TNF)-α and liver triglycerides were measured. Intestinal microbiota were analyzed using a 16S r DNA sequencing technique.

RESULTS

Compared with the FAT group, the SNS group exhibited decreased body weight, liver index, visceral fat index, serum ALT, portal LPS, liver TNF-α and liver triglycerides (P < 0.05). Intestinal microbiota analysis showed that the SNS group had different bacterial composition and function compared with the FAT group. In particular, Oscillospira genus was a bacterial biomarker of SNS group samples.

CONCLUSION

The beneficial effects of Si-Ni-San freeze-dried powder on high fat diet-induced NAFLD in mice may be associated with its anti-inflammatory and changing intestinal microbiota effects.

Nonalcoholic fatty liver disease is associated with decreased lung function

BACKGROUND & AIMS

The association between nonalcoholic fatty liver disease and lung function has not been fully examined. The aim of this study was to clarify the association between nonalcoholic fatty liver disease and lung function in general population by performing cross-sectional and longitudinal analysis.

METHODS

Participants without hepatic and respiratory disease who underwent regular health exams including hepatic sonography and spirometry with at least 3 years' follow-up were included. In cross-sectional analysis, the association between nonalcoholic fatty liver disease and lung function at baseline was examined with multiple regression models. The longitudinal analysis was performed by mixed linear regression models with propensity score matching.

RESULTS

Of 11 892 eligible participants (mean age, 47.7 years; male, 47.2%), 3815(32.1%) had nonalcoholic fatty liver disease based on sonography. In cross-sectional analysis, the nonalcoholic fatty liver disease group had lower adjusted forced expiratory volume in 1-second (men, 3.52 vs 3.44 L, P < .001; women, 2.62 vs 2.45 L, P < .001) and forced vital capacity (men, 4.33 vs 4.24 L, P < .001; women, 3.11 vs 2.97 L, P < .001) than the control group. In longitudinal analysis, during the mean follow-up period of 6.6 years, there were no significant differences in forced expiratory volume in 1-second or forced vital capacity decline rates between two groups in the propensity score-matched cohorts (n = 4558). However, those with high nonalcoholic fatty liver disease fibrosis score and fibrosis-4 (men, -21.7 vs -27.4 mL/y, P = .001; women, -22.4 vs -27.9 mL/y, P = .016) showed significantly faster decline in forced vital capacity compared to those with low scores.

CONCLUSIONS

Nonalcoholic fatty liver disease was associated with decreased lung function at baseline but was not associated with accelerated lung function decline in the propensity score-matched cohort. However, hepatic fibrosis was significantly associated with rapid forced vital capacity decline.

Non-alcoholic fatty liver disease and lifestyle modifications, focusing on physical activity

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, and the prevalence of non-alcoholic steatohepatitis (NASH) with fibrosis is increasing as the population with NAFLD ages. To date, lifestyle modifications including weight loss, increased physical activity, and dietary changes remain the treatment of choice for NAFLD because there are no approved effective pharmacologic agents. Increased physical activity has therapeutic effects on NAFLD by reducing hepatic fat independent of weight reduction. Indeed, even minimal physical activity below the recommended threshold may have a beneficial impact on NAFLD. Aerobic activity and resistance training have similar effects on NAFLD. Universal recommendations for the optimal intensity and dose of physical activity have not been established. Therefore, physical activity should be tailored based on a patient's clinical characteristics, comorbidities, and fitness capacity. Physical activity also prevents the development of NAFLD and may represent a valuable strategy for reducing the public health burden. However, there are insufficient data supporting the effects of physical activity on the progression of non-alcoholic fatty liver to NASH with advanced fibrosis, and on extrahepatic disease-related morbidity and mortality. In this paper, we review the role of physical activity in the management of NAFLD.

Clinical epidemiology and disease burden of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is defined as the presence of hepatic fat accumulation after the exclusion of other causes of hepatic steatosis, including other causes of liver disease, excessive alcohol consumption, and other conditions that may lead to hepatic steatosis. NAFLD encompasses a broad clinical spectrum ranging from nonalcoholic fatty liver to nonalcoholic steatohepatitis (NASH), advanced fibrosis, cirrhosis, and finally hepatocellular carcinoma (HCC). NAFLD is the most common liver disease in the world and NASH may soon become the most common indication for liver transplantation. Ongoing persistence of obesity with increasing rate of diabetes will increase the prevalence of NAFLD, and as this population ages, many will develop cirrhosis and end-stage liver disease. There has been a general increase in the prevalence of NAFLD, with Asia leading the rise, yet the United States is following closely behind with a rising prevalence from 15% in 2005 to 25% within 5 years. NAFLD is commonly associated with metabolic comorbidities, including obesity, type II diabetes, dyslipidemia, and metabolic syndrome. Our understanding of the pathophysiology of NAFLD is constantly evolving. Based on NAFLD subtypes, it has the potential to progress into advanced fibrosis, end-stage liver disease and HCC. The increasing prevalence of NAFLD with advanced fibrosis, is concerning because patients appear to experience higher liver-related and non-liver-related mortality than the general population. The increased morbidity and mortality, healthcare costs and declining health related quality of life associated with NAFLD makes it a formidable disease, and one that requires more in-depth analysis.