Progressive reduction in skeletal muscle mass to visceral fat area ratio is associated with a worsening of the hepatic conditions of non-alcoholic fatty liver disease

Muscle Quality as a Potential Diagnostic Marker of Advanced Liver Fibrosis in Patients with Non-alcoholic Fatty Liver Disease

Background

Muscle-liver crosstalk plays an important role in the development and progression of non-alcoholic fatty liver disease (NAFLD). The measurement of muscle echo-intensity during ultrasonography is a real-time, non-invasive method of assessing muscle quality. In this retrospective study, we investigated the significance of poor muscle quality (namely, a greater mass of non-contractile tissue, including intramuscular fat) as a risk factor for advanced liver fibrosis and considered whether it may represent a useful tool for the diagnosis of advanced liver fibrosis.

Methods

We analyzed data from 307 patients with NAFLD (143 men and 164 women) who visited the University of Tsukuba Hospital between 2017 and 2022. The patients were stratified into the following tertiles of muscle quality according to their muscle echo-intensity on ultrasonography: modest (84.1 arbitrary units [A.U.]), intermediate (97.4 A.U.), and poor (113.6 A.U.). We then investigated the relationships between muscle quality and risk factors for advanced liver fibrosis and calculated appropriate cutoff values.

Results

Patients with poor muscle quality showed a significant, 7.6-fold greater risk of liver fibrosis compared to those with modest muscle quality. Receiver operating characteristic curve analysis showed that muscle quality assessment was as accurate as the fibrosis-4 index and NAFLD fibrosis score in screening for liver fibrosis and superior to the assessment of muscle quantity and strength, respectively. Importantly, a muscle echo-intensity of ≥92.4 A.U. may represent a useful marker of advanced liver fibrosis.

Conclusion

Muscle quality may represent a useful means of identifying advanced liver fibrosis, and its assessment may become a useful screening tool in daily practice.

Global epidemiology of type 2 diabetes in patients with NAFLD or MAFLD: a systematic review and meta-analysis

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) and metabolic-associated fatty liver disease (MAFLD) shares common pathophysiological mechanisms with type 2 diabetes, making them significant risk factors for type 2 diabetes. The present study aimed to assess the epidemiological feature of type 2 diabetes in patients with NAFLD or MAFLD at global levels.

METHODS

Published studies were searched for terms that included type 2 diabetes, and NAFLD or MAFLD using PubMed, EMBASE, MEDLINE, and Web of Science databases from their inception to December 2022. The pooled global and regional prevalence and incidence density of type 2 diabetes in patients with NAFLD or MAFLD were evaluated using random-effects meta-analysis. Potential sources of heterogeneity were investigated using stratified meta-analysis and meta-regression.

RESULTS

A total of 395 studies (6,878,568 participants with NAFLD; 1,172,637 participants with MAFLD) from 40 countries or areas were included in the meta-analysis. The pooled prevalence of type 2 diabetes among NAFLD or MAFLD patients was 28.3% (95% confidence interval 25.2-31.6%) and 26.2% (23.9-28.6%) globally. The incidence density of type 2 diabetes in NAFLD or MAFLD patients was 24.6 per 1000-person year (20.7 to 29.2) and 26.9 per 1000-person year (7.3 to 44.4), respectively.

CONCLUSIONS

The present study describes the global prevalence and incidence of type 2 diabetes in patients with NAFLD or MAFLD. The study findings serve as a valuable resource to assess the global clinical and economic impact of type 2 diabetes in patients with NAFLD or MAFLD.

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.

The association between creatinine to body weight ratio and the risk of progression to diabetes from pre-diabetes: a 5-year cohort study in Chinese adults

OBJECTIVE

Evidence on the association between the creatinine to body weight (Cre/BW) ratio and the risk of pre-diabetes to diabetes development remains limited. Our study aimed to examine the association between the Cre/BW ratio and incident diabetes in pre-diabetic patients.

METHODS

This retrospective cohort study included 24,506 pre-diabetic participants who underwent health checks from 2010 to 2016 in China. We used the Cox proportional-hazards regression model to explore the relationship between baseline Cre/BW ratio and diabetes risk in pre-diabetes patients. Using a Cox proportional hazards regression with cubic spline function and smooth curve fitting (cubical spline smoothing), we were able to determine the non-linear relationship between them. We also carried out a number of subgroup and sensitivity analyses.

RESULTS

The age range of the participants included in this study was 20-99 years, with a majority of 16,232 individuals (66.24%) being men. The mean baseline Cre/BW ratio was 1.06 (SD 0.22) umol/L/kg. 2512 (10.25%) participants received a diabetes final diagnosis over a median follow-up period of 2.89 years. After adjusting for covariates, the Cre/BW ratio had a negative association with incident diabetes in participants with pre-diabetes, per umol/L/kg increase in Cre/BM ratio was accompanied by a 55.5% decrease in diabetes risk (HR = 0.445, 95%CI 0.361 to 0.548). The Cre/BW ratio and risk of diabetes had a non-linear connection, with 1.072 umol/L/kg serving as the ratio's inflection point. The HR were 0.294 (95%CI:0.208-0.414) and 0.712 (95%CI:0.492-1.029), respectively, on the left and right sides of the inflection point. The sensitivity analysis demonstrated the robustness of these results. Subgroup analyses indicated that the Cre/BW ratio was strongly associated with the risk of diabetes among participants who were younger than 50 years, as well as among those with diastolic blood pressure (DBP) < 90 mmHg and triglyceride (TG) < 1.7 mmol/L. In contrast, among participants 50 years of age or older, those with DBP ≥ 90 mmHg, and those with TG ≥ 1.7 mmol/L, the relationship between the Cre/BW ratio and the risk of diabetes was attenuated.

CONCLUSION

This study demonstrates a negative, non-linear relationship between the Cre/BW ratio and the risk of diabetes among the Chinese population with pre-diabetes. From a therapeutic standpoint, it is clinically meaningful to maintain the Cre/BW ratio levels above the inflection point of 1.072 umol/L/kg.

Serum Oxidative Status in People with Obesity: Relation to Tissue Losses, Glucose Levels, and Weight Reduction

BACKGROUND

This work aims to study the effect of reductions in various body mass components on the oxidative, glycemic, and lipid parameters of people with obesity (PWO).

METHODS

A total of 53 PWO underwent a six-month individualized low-calorie diet combined with moderate exercise, during which anthropometric, biochemical, and oxidative parameters were measured. Probands were divided into groups based on weight, visceral fat area (VFA), total body water (TBW), and skeletal muscle mass (SMM) losses.

RESULTS

Weight reduction normalizes glycemia, but VFA reduction is less pronounced, while SMM and TBW reductions are more pronounced in patients with higher initial concentrations of glucose and fructosamine. Moreover, changes in oxidative parameters correlate with changes in glucose.

CONCLUSIONS

Weight loss, regardless of the reduced tissue, decreases cardiovascular risk. We observed a significant change in almost all parameters related to the redox state. In general, parameters responsible for antioxidant action improved, and markers of oxidative damage decreased. Malondialdehyde, lipid peroxides, and total oxidative status levels can be considered biomarkers reflecting only the current severity of reactive oxygen species genesis processes. When considering the glycemic state, the results are not as clear due to the substantial differences between normoglycemic and hyperglycemic patients. Glycemic status is a factor playing a crucial role in weight reduction.

Sarcopenia, sarcopenic obesity and nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD), sarcopenia and sarcopenic obesity (SO) are highly prevalent conditions that may coexist, especially in the aging population, without any approved pharmacologic treatment for all of them. There are multiple pathophysiologic mechanisms suggested to explain an association between NAFLD and sarcopenia or SO, including alterations in the adipokines, cytokines, hepatokines and myokines, which may interplay with other factors, such as aging, diet and physical inactivity. In clinical terms, most observational studies support an association between NAFLD and sarcopenia or SO; importantly, there are few cohort studies indicating higher mortality in patients with NAFLD and sarcopenia. Their association also bears some treatment considerations: for example, pioglitazone or vitamin E, suggested as off label treatment for selected patients with nonalcoholic steatohepatitis, may be recommended in the coexistence of sarcopenia or SO, since limited evidence did not show adverse effects of them on sarcopenia and abdominal obesity. In this review, evidence linking sarcopenia and SO with NAFLD is summarized, with a special focus on clinical data. A synopsis of the major pathophysiological links between NAFLD and sarcopenia/SO is initially presented, followed by selected clinical studies and, finally, treatment considerations in patients with NAFLD and sarcopenia or SO are discussed.

Improved body composition decreases the fat content in non-alcoholic fatty liver disease, a meta-analysis and systematic review of longitudinal studies

Background

Based on cross-sectional studies, there is a link between body composition parameters and steatosis in non-alcoholic fatty liver disease (NAFLD). However, whether long-term changes in different body composition parameters will result in NAFLD resolution is unclear. Therefore, we aimed to summarize the literature on longitudinal studies evaluating the association between NAFLD resolution and body composition change.

Methods

Based on the recommendations of the Cochrane Handbook, we performed a systematic search on September 26th, 2021, in three databases: Embase, MEDLINE (via PubMed), and Cochrane Central Register of Controlled Trials (CENTRAL). Eligible studies reported on patients with NAFLD (liver fat >5%) and examined the correlation between body composition improvement and decrease in steatosis. We did not have pre-defined body composition or steatosis measurement criteria. Next, we calculated pooled correlation coefficient (r) with a 95% confidence interval (CI). Furthermore, we narratively summarized articles with other statistical methods.

Results

We included 15 studies in our narrative review and five in our quantitative synthesis. Based on two studies with 85 patients, we found a pooled correlation coefficient of r = 0.49 (CI: 0.22-0.69, Spearman's correlation) between the change of visceral adipose tissue and liver steatosis. Similarly, based on three studies with 175 patients, the correlation was r = 0.33 (CI: 0.19-0.46, Pearson's correlation). On the other hand, based on two studies with 163 patients, the correlation between subcutaneous adipose tissue change and liver steatosis change was r = 0.42 (CI: 0.29-0.54, Pearson's correlation). Furthermore, based on the studies in the narrative synthesis, body composition improvement was associated with steatosis resolution.

Conclusions

Based on the included studies, body composition improvement may be associated with a decrease in liver fat content in NAFLD.

Systematic review registration

Identifier: CRD42021278584.

Nonalcoholic Fatty Liver Disease in Lean/Nonobese and Obese Individuals: A Comprehensive Review on Prevalence, Pathogenesis, Clinical Outcomes, and Treatment

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide, with an estimated prevalence of 25% globally. NAFLD is closely associated with metabolic syndrome, which are both becoming increasingly more common with increasing rates of insulin resistance, dyslipidemia, and hypertension. Although NAFLD is strongly associated with obesity, lean or nonobese NAFLD is a relatively new phenotype and occurs in patients without increased waist circumference and with or without visceral fat. Currently, there is limited literature comparing and illustrating the differences between lean/nonobese and obese NAFLD patients with regard to risk factors, pathophysiology, and clinical outcomes. In this review, we aim to define and further delineate different phenotypes of NAFLD and present a comprehensive review on the prevalence, incidence, risk factors, genetic predisposition, and pathophysiology. Furthermore, we discuss and compare the clinical outcomes, such as insulin resistance, dyslipidemia, hypertension, coronary artery disease, mortality, and progression to nonalcoholic steatohepatitis, among lean/nonobese and obese NAFLD patients. Finally, we summarize the most up to date current management of NAFLD, including lifestyle interventions, pharmacologic therapies, and surgical options.

Osteosarcopenia in NAFLD/MAFLD: An Underappreciated Clinical Problem in Chronic Liver Disease

Chronic liver disease (CLD), including non-alcoholic fatty liver disease (NAFLD) and its advanced form, non-alcoholic steatohepatitis (NASH), affects a significant portion of the population worldwide. NAFLD is characterised by fat accumulation in the liver, while NASH is associated with inflammation and liver damage. Osteosarcopenia, which combines muscle and bone mass loss, is an emerging clinical problem in chronic liver disease that is often underappreciated. The reductions in muscle and bone mass share several common pathophysiological pathways; insulin resistance and chronic systemic inflammation are the most crucial predisposing factors and are related to the presence and gravity of NAFLD and to the worsening of the outcome of liver disease. This article explores the relationship between osteosarcopenia and NAFLD/MAFLD, focusing on the diagnosis, prevention and treatment of this condition in patients with CLD.

A Low Daily Intake of Simple Sugars in the Diet Is Associated with Improved Liver Function in Cirrhotic Liver Transplant Candidates

(1) Background: We investigated, for the first time, whether dietary simple sugar intake affects MELD score changes over time in a cohort of cirrhotic liver transplant candidates. (2) Methods: the MELD score, dietary habits using a 3-day food diary, and visceral adipose tissue index (VATI) measured with CT scan were assessed in 80 consecutive outpatient cirrhotic patients at baseline, after counseling to follow current nutritional guidelines. The MELD score was reassessed after six months and the DELTA-MELD was calculated as the MELD at the second assessment minus the MELD at baseline. (3) Results: Compared with the baseline, the MELD score of cirrhotic patients at the end of the study was decreased, stable, or increased in 36%, 8% and 56% of patients, respectively. In separate multiple linear regression models, DELTA-MELD was positively and independently correlated with the daily intake of simple sugars expressed in g/kg body weight (p = 0.01) or as a percentage of total caloric intake (p = 0.0004) and with the number of daily portions of fruit, added sugar, jam, and honey (p = 0.003). These associations were present almost exclusively in patients with VATI above the median value. (4) Conclusions: In cirrhotic patients with high amounts of visceral adipose tissue the consumption of simple sugars and fructose should be limited to improve their clinical outcome.

Predictive and prognostic effect of computed tomography-derived body composition analysis during neoadjuvant chemotherapy for operable and locally advanced breast cancer

OBJECTIVES

Excess adiposity is associated with several factors involved in carcinogenesis and breast cancer progression. Evidence supporting the role of body composition in breast cancer treatment is promising, but still scanty and mainly focused on adjuvant treatment. The aim of this study was to evaluate the changes in body composition during neoadjuvant chemotherapy and its association with pathologic complete response and survival outcome in patients treated for operable/locally advanced breast cancer.

METHODS

A retrospective review of patients with breast cancer treated with neoadjuvant chemotherapy was performed in the Oncology Section of the Department of Medicine, University of Verona between 2014 and 2019. Body composition was evaluated from clinically acquired computed tomography scans at diagnosis and after neoadjuvant chemotherapy. Descriptive statistic was adopted. The associations of body composition measures with pathologic complete response and disease-free survival were analyzed. Kaplan-Meier curves were compared with log-rank analysis.

RESULTS

Data from 93 patients were collected. After neoadjuvant chemotherapy, the adipose compound changed significantly across all body mass index categories. Body composition parameters had no significant effect on pathologic complete response. Survival analysis showed that a high gain of visceral adipose tissue during neoadjuvant chemotherapy was associated with shorter disease-free survival (hazard ratio, 10.2; P = 0.026). In particular, disease-free survival was significantly worse in patients who gained ≥10% of visceral adipose tissue compared with patients who gained <10% of visceral adipose tissue (5-y disease-free survival 71.4 versus 96.3, P = 0.009, respectively).

CONCLUSIONS

Our results indicated that neoadjuvant chemotherapy significantly affects body composition, which seems to have an effect on survival outcome of breast cancer, highlighting the relevance of the body composition assessment when estimating treatment outcomes.

Sex influences the association between appendicular skeletal muscle mass to visceral fat area ratio and non-alcoholic steatohepatitis in patients with biopsy-proven non-alcoholic fatty liver disease

Sarcopenic obesity is regarded as a risk factor for the progression and development of non-alcoholic fatty liver disease (NAFLD). Since male sex is a risk factor for NAFLD and skeletal muscle mass markedly varies between the sexes, we examined whether sex influences the association between appendicular skeletal muscle mass to visceral fat area ratio (SVR), that is, an index of skeletal muscle mass combined with abdominal obesity, and the histological severity of NAFLD. The SVR was measured by bioelectrical impedance in a cohort of 613 (M/F = 443/170) Chinese middle-aged individuals with biopsy-proven NAFLD. Multivariable logistic regression and subgroup analyses were used to test the association between SVR and the severity of NAFLD (i.e. non-alcoholic steatohepatitis (NASH) or NASH with the presence of any stage of liver fibrosis). NASH was identified by a NAFLD activity score ≥5, with a minimum score of 1 for each of its categories. The presence of fibrosis was classified as having a histological stage ≥1. The SVR was inversely associated with NASH in men (adjusted OR 0·62; 95 % CI 0·42, 0·92, P = 0·017 for NASH, adjusted OR 0·65; 95 % CI 0·43, 0·99, P = 0·043 for NASH with the presence of fibrosis), but not in women (1·47 (95 % CI 0·76, 2·83), P = 0·25 for NASH, and 1·45 (95 % CI 0·74, 2·83), P = 0·28 for NASH with the presence of fibrosis). There was a significant interaction for sex and SVR (P_interaction = 0·017 for NASH and P_interaction = 0·033 for NASH with the presence of fibrosis). Our findings show that lower skeletal muscle mass combined with abdominal obesity is strongly associated with the presence of NASH only in men.

Skeletal muscle mass to visceral fat area ratio as a predictor of NAFLD in lean and overweight men and women with effect modification by sex

The effect of sarcopenic visceral obesity on the risk of nonalcoholic fatty liver disease (NAFLD) is uncertain. We investigated (a) whether the skeletal muscle mass to visceral fat area ratio (SV ratio), as a measure of sarcopenic visceral obesity, is a risk factor for NAFLD; and (b) whether the SV ratio adds to conventional adiposity measures to improve prediction of incident NAFLD. Adults without NAFLD (n = 151,017) were followed up for a median of 3.7 years. Hepatic steatosis was measured using ultrasonography, and liver fibrosis scores were estimated using the Fibrosis‐4 index (FIB‐4) and the NAFLD Fibrosis Score (NFS). Cox proportional hazards models were used to determine sex‐specific adjusted hazard ratios (aHRs) (95% confidence intervals [CIs]). The incremental predictive performance was assessed using the area under the receiver operating characteristic curve, net reclassification improvement, and integrated discrimination improvement. Multivariable aHRs (95% CIs) for incident NAFLD comparing the lowest versus the highest quintile of SV ratio were 3.77 (3.56–3.99) for men and 11.69 (10.46–13.06) for women (p–interaction by sex < 0.001). For incident NAFLD with intermediate/high FIB‐4, aHRs were 2.83 (2.19–3.64) for men and 7.96 (3.85–16.44) for women (similar results were obtained for NFS). Associations remained significant even after adjustment for body mass index, waist circumference, and time‐varying covariates. These associations were also more pronounced in nonobese than obese participants (p–interaction < 0.001). The addition of SV ratio to conventional adiposity measures modestly improved risk prediction for incident NAFLD. SV ratio was inversely associated with risk of developing NAFLD, with effect modification by sex and obesity. Conclusion: Low SV ratio is a complementary index to conventional adiposity measures in the evaluation of NAFLD risk.

Body composition measured by bioelectrical impedance analysis is a viable alternative to magnetic resonance imaging in children with nonalcoholic fatty liver disease

OBJECTIVE

To determine the relationship between bioelectrical impedance analysis (BIA) and magnetic resonance imaging (MRI) obtained measures of body composition in children with nonalcoholic fatty liver disease (NAFLD).

METHODS

Youth with obesity and NAFLD who had BIA and abdominal MRI testing were included. BIA measured skeletal muscle mass (SMM), appendicular lean mass (ALM), trunk muscle mass (TMM), and percent body fat. MRI measured total psoas muscle surface area (tPMSA) and fat compartments. Univariate analysis described the relationship between BIA- and MRI-derived measurements. Multivariable regression analyses built a model with body composition measured via MRI.

RESULTS

115 patients (82 (71%) male, 38 (33%) Hispanic, median age14 years) were included. There was a strong correlation between tPMSA and SMM, ALM, and TMM (correlation coefficients [CCs]: 0.701, 0.689, 0.708, respectively; all P < .001). Higher SMM, ALM, and TMM were associated with higher tPMSA. This association remained after controlling for age, sex, ethnicity, type 2 diabetes mellitus status, and body mass index z-score. Total fat mass by BIA and MRI-determined total, subcutaneous, and intraperitoneal fat area correlated significantly (CCs: 0.813, 0.808, 0.515, respectively; all P < .001). In univariate regression, higher total fat mass by BIA was associated with increased total fat area and increased fat in each of the four regions measured by MRI. After controlling for confounders, the association between total fat mass by BIA and total fat area by MRI persisted.

CONCLUSIONS

BIA measures of muscle and fat mass correlate strongly with MRI measures of tPMSA and fat areas in children with obesity and NAFLD.

Creatinine-to-body weight ratio is a predictor of incident diabetes: a population-based retrospective cohort study

PURPOSE

Creatinine to body weight (Cre/BW) ratio is considered the independent risk factor for incident type 2 diabetes mellitus (T2DM), but research on this relationship is limited. The relationship between the Cre/BW ratio and T2DM among Chinse individuals is still ambiguous. This study aimed to evaluate the correlation between the Cre/BW ratio and the risk of T2DM in the Chinese population.

METHODS

This is a retrospective cohort study from a prospectively collected database. We included a total of 200,658 adults free of T2DM at baseline. The risk of incident T2DM according to Cre/BW ratio was estimated using multivariable Cox proportional hazards models, and a two-piece wise linear regression model was developed to find out the threshold effect.

RESULTS

With a median follow-up of 3.13 ± 0.94 years, a total of 4001 (1.99%) participants developed T2DM. Overall, there was an L-shaped relation of Cre/BW ratio with the risk of incident T2DM (P for non-linearity < 0.001). When the Cre/BW ratio (× 100) was less than 0.86, the risk of T2DM decreased significantly as the Cre/BW ratio increased [0.01 (0.00, 0.10), P < 0.001]. When the Cre/BW ratio (× 100) was between 0.86 and 1.36, the reduction in the risk of developing T2DM was not as significant as before [0.22 (0.12, 0.38), P < 0.001]. In contrast, when the Cre/BW ratio (× 100) was greater than 1.36, the reduction in T2DM incidence became significantly flatter than before [0.73 (0.29,1.8), P = 0.49].

CONCLUSION

There was an L-shaped relation of Cre/BW ratio with incidence of T2DM in general Chinese adults. A negative curvilinear association between Cre/BW ratio and incident T2DM was present, with a saturation effect predicted at 0.86 and 1.36 of Cre/BW ratio (× 100).

Non-alcoholic fatty liver disease and microRNAs expression, how it affects the development and progression of the disease

The obesity pandemic that affects the global population generates one of the most unfavorable microenvironmental conditions in the hepatocyte, which triggers the metabolic hepatopathy known as non-alcoholic fatty liver; its annual rates increase in its prevalence and does not seem to improve in the future. The international consortia, LITMUS by the European Union and NIMBLE by the United States of America, have started a race for the development of hepatic steatosis and steatohepatitis reliable biomarkers to have an adequate diagnosis. MicroRNAs have been proposed as diagnostic and prognostic biomarkers involved in adaptation to changes in the liver microenvironment, which could improve clinical intervention strategies in patients with hepatic steatosis.

Non-Alcoholic Fatty Liver Disease in Lean and Non-Obese Individuals: Current and Future Challenges

Non-alcoholic fatty liver disease (NAFLD), which approximately affects a quarter of the world’s population, has become a major public health concern. Although usually associated with excess body weight, it may also affect normal-weight individuals, a condition termed as lean/non-obese NAFLD. The prevalence of lean/non-obese NAFLD is around 20% within the NAFLD population, and 5% within the general population. Recent data suggest that individuals with lean NAFLD, despite the absence of obesity, exhibit similar cardiovascular- and cancer-related mortality compared to obese NAFLD individuals and increased all-cause mortality risk. Lean and obese NAFLD individuals share several metabolic abnormalities, but present dissimilarities in genetic predisposition, body composition, gut microbiota, and susceptibility to environmental factors. Current treatment of lean NAFLD is aimed at improving overall fitness and decreasing visceral adiposity, with weight loss strategies being the cornerstone of treatment. Moreover, several drugs including PPAR agonists, SGLT2 inhibitors, or GLP-1 receptor agonists could also be useful in the management of lean NAFLD. Although there has been an increase in research regarding lean NAFLD, there are still more questions than answers. There are several potential drugs for NAFLD therapy, but clinical trials are needed to evaluate their efficacy in lean individuals.

Comparison of metabolic risk factors, physical performances, and prevalence of low back pain among categories determined by visceral adipose tissue and trunk skeletal muscle mass in middle-aged men

The present study compared metabolic risk factors, physical performances, and musculoskeletal impairment among categories determined by visceral adipose tissue (VAT) and trunk skeletal muscle (SM) mass in middle-aged Japanese men. In total, 1026 healthy Japanese males aged between 35 and 59 years were categorized into 4 groups according to the amount of VAT and SM in the trunk measured using low-dose computed tomography (LowVAT-HighSM, LowVAT-LowSM, HighVAT-HighSM, and HighVAT-LowSM). Height, body mass waist circumference, body fat, intramuscular adipose tissue (IntraMAT), subcutaneous adipose tissue, biochemical blood profiles (triglycerides, high-density lipoprotein cholesterol, fasting blood glucose, aspartate transaminase, alanine transaminase and γ-glutamyl trans peptidase), physical performances (trunk flexibility, the chair-stand test, two-step length and hand-grip strength), the prevalence of low back pain, and lifestyle habits for exercise, alcohol intake and smoking, were compared among the groups. The results showed that LowVAT-HighSM had significantly superior biochemical blood profiles and physical performances to the other groups. HighVAT-LowSM had significantly higher %IntraMAT and the prevalence of low back pain. The two-step length, which is an index of walking ability, significantly differed according to the four subject categories. These results indicate that metabolic risk factors, physical performances, and prevalence of low back pain in middle-aged Japanese men may differ among four categories determined by VAT and trunk SM.

Association of Skeletal Muscle and Adipose Tissue Distribution with Histologic Severity of Non-Alcoholic Fatty Liver

Adipose tissue and skeletal muscle is associated with non-alcoholic fatty liver disease (NAFLD). This study evaluates the association between body composition and histologic severity in patients with NAFLD. Using the cross-sectional CT images at the level of L3 vertebra and the histologic findings of 178 patients with biopsy-proven NAFLD, we analyzed the correlation of the histologic findings to the skeletal muscle index (SMI), subcutaneous adipose tissue index (SATI), and visceral adipose tissue index (VATI), which is defined as the body composition area (cm²) by height squared (m²). The clinical and laboratory features with body composition were analyzed to determine the risk factors for advanced fibrosis. The VATI significantly increased in severe non-alcoholic steatohepatitis (NASH) or advanced fibrosis. In addition, the VATI was correlated with the NAFLD activity score (NAS) and the fibrosis stage. In multivariate analyses, age (odds ratio (OR), 1.09; 95% confidence interval (CI), 1.02–1.19; p = 0.025), severe NASH (OR, 8.66; 95% CI, 2.13–46.40; p = 0.005), and visceral adiposity (OR, 6.77; 95% CI, 1.81–29.90; p = 0.007) were independently associated with advanced fibrosis in patients with NAFLD. Visceral adiposity is correlated with the histologic severity of NAFLD, which is independently associated with advanced fibrosis.

Effectiveness of companion-intensive multi-aspect weight management in Chinese adults with obesity: a 6-month multicenter randomized clinical trial

Background

Obesity is a globally increasing health epidemic requiring early lifestyle intervention. Our main objective was to examine the effectiveness of companion-intensive multi-aspect weight management (CIMWM) in Chinese adults with obesity.

Methods

In this 6-month, prospective, open-label, multicenter, randomized controlled clinical trial, we recruited 272 obese adults aged 18–50 years with a body mass index (BMI) ≥ 28.0 kg/m² and capable of using smartphones. CIMWM (n = 136) offered both daily online instructions and monthly face-to-face guidance by physicians, dietitians, and health managers along with the provision of meal replacements in the first 3 months. Traditional multi-aspect weight management (TMWM, n = 136) provided monthly face-to-face guidance by the same panel of professionals and the same meal replacements as CIMWM group, but required subjects to complete daily self-monitoring instead of offering daily online instructions. Body composition and metabolic parameters were assessed at baseline, 1, 2, 3, and 6 months by physicians. The primary outcomes were clinically-significant weight loss and changes in BMI and body composition.

Results

Participants in both groups showed significantly reduced BMI, body fat mass (BFM), visceral fat area (VFA), and HOMA-IR (p < 0.05). CIMWM was shown to be superior to TMWM in the improvement of clinically-significant weight loss, BMI, total cholesterol (TC), the body composition parameters BFM and the skeletal muscle mass-to-visceral fat area ratio (S/V) (p < 0.05). The non-alcoholic fatty liver disease score (NFS) was negatively related to S/V at baseline. After weight management, NFS was lowered among individuals with levels in the highest tertile (p < 0.05). Metabolic memory in terms of the continuous reduction of BMI, BFM, and TC was retained up to 6 months in spite of participants transferring to self-monitoring assessment in the final 3 months.

Conclusions

The CIMWM strategy in obese Chinese adults is proved to be more effective than TMWM in weight loss, and motivates greater adherence to intervention and lifestyle reprogramming.

Trial registration Chinese Clinical Trial Registry, ChiCTR1800017463, Registered July 31, 2018. http://www.chictr.org.cn/showproj.aspx?proj=29649.

Dysregulated Autophagy Mediates Sarcopenic Obesity and Its Complications via AMPK and PGC1α Signaling Pathways: Potential Involvement of Gut Dysbiosis as a Pathological Link

Sarcopenic obesity (SOB), which is closely related to being elderly as a feature of aging, is recently gaining attention because it is associated with many other age-related diseases that present as altered intercellular communication, dysregulated nutrient sensing, and mitochondrial dysfunction. Along with insulin resistance and inflammation as the core pathogenesis of SOB, autophagy has recently gained attention as a significant mechanism of muscle aging in SOB. Known as important cellular metabolic regulators, the AMP-activated protein kinase (AMPK) and the peroxisome proliferator-activated receptor-gamma coactivator-1 alpha (PGC-1α) signaling pathways play an important role in autophagy, inflammation, and insulin resistance, as well as mutual communication between skeletal muscle, adipose tissue, and the liver. Furthermore, AMPK and PGC-1α signaling pathways are implicated in the gut microbiome-muscle axis. In this review, we describe the pathological link between SOB and its associated complications such as metabolic, cardiovascular, and liver disease, falls and fractures, osteoarthritis, pulmonary disease, and mental health via dysregulated autophagy controlled by AMPK and/or PGC-1α signaling pathways. Here, we propose potential treatments for SOB by modulating autophagy activity and gut dysbiosis based on plausible pathological links.

Clinical and anthropometric characteristics of non-obese non-alcoholic fatty liver disease subjects in Japan

AIM

The underlying mechanism of non-obese non-alcoholic fatty liver disease (NAFLD) has not been fully elucidated. We classified patients with NAFLD by sex and body mass index and compared their clinical features to clarify the background pathophysiology of non-obese NAFLD.

METHODS

A total of 404 patients with NAFLD were divided according to their body mass index (<25 [non-obese], 25 to <30 [obese], and ≥30 [severe obese]), and were further compared with 253 patients without obesity and NAFLD (non-NAFLD).

RESULTS

The proportion of the individuals with non-obese NAFLD was 25.7% in men and 27.6% in women. The male and female non-obese NAFLD groups had lower skeletal muscle mass and muscle strength than the obese NAFLD groups. The visceral fat area, although low, was ≥100 cm² in 59.3% of men and 43.8% of women. An increase in liver fat accumulation, hepatic fibrosis, homeostasis model assessment of insulin resistance, and leptin levels was modest in the non-obese NAFLD group compared with a marked increase in the obese NAFLD groups. The muscle mass of the non-obese NAFLD group was similar to that of the non-NAFLD group, but muscle steatosis was particularly common among women. Multivariate analysis revealed that the factors contributing to increased liver fat accumulation in the non-obese NAFLD group were visceral fat area, HbA1c, myostatin, and leptin.

CONCLUSIONS

In patients with non-obese NAFLD, a sex difference was observed in the clinical features. In addition to increased visceral fat, decreased muscle mass and muscle strength, muscle atrophy (presarcopenia), and impaired glucose tolerance were considered to be important pathophysiological factors.

Creatinine to Body Weight Ratio Is Associated with Incident Diabetes: Population-Based Cohort Study

We investigated the association between creatinine to body weight (Cre/BW) ratio and incident diabetes. In this cohort study, 9659 men and 7417 women were follow up mean (SD) 5.6 (3.5) years and 5.4 (3.4) years, respectively. For men, tertile 1 (T1; n = 3176), Cre/BW < 0.01275; tertile 2 (T2; n = 3258), 0.01275 ≤ Cre/BW < 0.0148; and tertile 3 (T3; n = 3225), Cre/BW ≥ 0.0148; and for women, T1 (n = 2437), Cre/BMI < 0.0118; T2 (n = 2516), 0.0118 ≤ Cre/BMI < 0.014; and T3 (n = 2477), Cre/BMI ≥ 0.014. Among them, 362 men and 102 women developed diabetes. The hazard ratios (HRs) of incident diabetes in the T2 group was 0.56 (95% CI 0.44–0.71, p < 0.001) in men and 0.61 (0.38–0.99, p = 0.045) in women and in the T3 group was 0.42 (0.32–0.54, p < 0.001) in men and 0.55 (0.34–0.89, p = 0.014) in women after adjusting for covariates, compared with the T1 group. Moreover, Δ0.001 incremental of Cre/BW is negatively associated with incident diabetes (adjusted HR 0.84, 95% CI 0.80–0.88, p < 0.001 for men and 0.88, 0.81–0.96, p = 0.003 for women). In conclusion, Cre/BW ratio is inversely related to incident diabetes. Checking Cre/BW ratios may predict future diabetes risks.

Urinary Levels of Titin-N Fragment, a Skeletal Muscle Damage Marker, are Increased in Subjects with Nonalcoholic Fatty Liver Disease

Sarcopenia is a pathological condition affecting the development and progression of NAFLD. Urinary levels of titin-N fragment, a biomarker reflecting muscle damage, were measured in NAFLD subjects, and analyzed in a retrospective manner for possible correlations with NAFLD pathophysiology to assess their clinical relevance. This study enrolled 153 NAFLD subjects and 100 subjects without NAFLD, obesity or diabetes mellitus (non-NAFLD). NAFLD subjects had more decreased knee extension strength. NAFLD subjects had greater subcutaneous fat thickness and echo intensity (brightness) of the rectus femoris muscle on ultrasound images; higher levels of the intra- and extra-myocellular lipids (IMCL, EMCL) using ¹H-MRS. Urinary titin-N fragment levels were increased with increasing age but not different between males and females. NAFLD subjects had higher titin-N fragment levels than non-NAFLD subjects. The levels were negatively correlated with skeletal muscle mass and knee extension strength and positively correlated with muscle echo intensity, EMCL, and liver fibrosis scores (NAFLD fibrosis score, FIB-4 index). Multivariate analysis revealed that factors affecting the levels were skeletal mass index, leg skeletal muscle mass, liver stiffness, and NAFLD fibrosis score. Urinary levels of titin-N fragment reflected skeletal muscle deterioration and functional decline, and was closely associated with hepatic pathological conditions in NAFLD subjects.