Lean non-alcoholic fatty liver disease (Lean-NAFLD) and the development of metabolic syndrome: a retrospective study

Visceral and subcutaneous abdominal fat is associated with non-alcoholic fatty liver disease while augmenting Metabolic Syndrome's effect on non-alcoholic fatty liver disease: A cross-sectional study of NHANES 2017-2018

BACKGROUND

The aim was to evaluate the effect different types of abdominal fat have on NAFLD development and the effects of abdominal fat has on the association between Metabolic Syndrome (MetS) and NALFD.

METHODS

Data was collected from the cross-sectional NHANES dataset (2017-2018 cycle). Using the controlled attenuation parameter (USG CAP, dB/m), which measures the level of steatosis, the cohort was stratified into two groups: NAFLD(+) (≥274 dB/m) and NAFLD(-). Using complex samples analyses, associations between liver steatosis or NAFLD and types of abdominal fat area [Total abdominal (TAFA), subcutaneous (SAT), and visceral (VAT)] were determined. Pearson's correlation coefficient (r) was calculated to evaluate the associations between adipose tissues and NAFLD. Logistic regression was used to determine the risk [odds ratio (OR) and 95% confidence interval (95%CI)]. Participants were also classified by MetS, using the Harmonizing Definition criteria.

RESULTS

Using 1,980 participants (96,282,896 weighted), there was a significant (p<0.001) correlation between USG CAP and TAFA (r = 0.569), VAT (r = 0.645), and SAT (r = 0.479). Additionally, the risk of developing NAFLD was observed for total abdominal obesity (OR = 19.9, 95%CI: 5.1-77.8, p<0.001), visceral obesity (OR = 9.1, 95%CI: 6.2-13.5, p<0.001) and subcutaneous obesity (OR = 4.8, 95%CI: 3.2-6.9, p<0.001). Using 866 participants (44,399,696 weighted), for visceral obesity, participants with MetS and visceral obesity (OR = 18.1, 95%CI: 8.0-41.3, p<0.001) were shown to have a greater risk than participants with MetS only (OR = 6.3, 95%CI: 2.6-15.2, p<0.001). For subcutaneous obesity, again, participants with MetS and subcutaneous obesity (OR = 18.3, 95%CI: 8.0-41.9, p<0.001) were shown to have a greater risk than the MetS-only group (OR = 10.3, 95%CI: 4.8-22.4, p<0.001).

CONCLUSION

TAFA, VAT, and SAT were positively associated with USG CAP values and increased the risk of developing NAFLD. Also, the type of abdominal fat depots did affect the association between MetS and NAFLD.

Metabolic syndrome and obesity among marginalised school-going adolescents in Karachi, Pakistan: a cross-sectional study

Background

Metabolic syndrome (MetS) is a cluster of cardiometabolic risk factors which increase the likelihood of developing type 2 diabetes and cardiovascular disease. This study aimed to determine the prevalence of MetS among adolescents living in slums aged 11-18 years in Karachi, Pakistan.

Methods

Data were collected from 689 adolescents attending five schools in two slum areas of Karachi, Korangi and Baldia, from February 2023 to March 2023. Measurements of weight, height, waist circumference, and blood pressure were obtained from the study participants. Blood samples were collected to assess fasting plasma glucose, High density lipoprotein HDL-cholesterol, and triglyceride levels as per National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III). The prevalence of MetS was estimated using five diagnostic criteria, i.e., International Diabetes Federation (IDF-2007), World Health Organization, NCEP-ATP III, de Ferranti et al., and Cruz and Goran.

Findings

The study revealed an overall prevalence of MetS among the adolescents in the two slum areas as 16.7%. A higher prevalence of MetS was observed among females (9.1%) and those with lower body mass index BMI (13.6%). The diagnostic criteria proposed by Cruz and Goran were found to be the most sensitive, with a MetS diagnosis rate of 22.93%. The study also identified several significant risk factors associated with MetS, including sedentary lifestyle (7.7%), lack of physical activity (7.5%), increased screen time (1.5%), lower fruit consumption (6.1%), and underweight (7.7%). Among slum-dwelling adolescents, low levels of HDL-cholesterol (33.96 ± 5.21), high triglyceride levels (161.45 ± 63.09), and elevated fasting plasma glucose levels (112.59 ± 28.92) were prevalent components of MetS.

Interpretation

This study provides compelling evidence of a high prevalence of MetS among marginalised school-going adolescents in Karachi, Pakistan. The findings underscore the importance of early identification of adolescents at risk of developing MetS (especially those living in slum areas) and the implementation of effective preventive strategies to mitigate the risk of type 2 diabetes and cardiovascular disease in later life.

Funding

None.

Triglycerides Mediate the Influence of Body Mass Index on Non-Alcoholic Fatty Liver Disease in a Non-Obese Chinese Population with Normal Low-Density Lipoprotein Cholesterol Levels

INTRODUCTION

Over 25% of the world's population has non-obese or lean non-alcoholic fatty liver disease (NAFLD), and the prevalence is higher than average in Asia. The present study focused on the relationship between body mass index (BMI) and non-obese NAFLD in non-overweight people in China, particularly the influence of triglycerides (TG) in the pathogenesis of non-obese NAFLD. The findings suggest new treatments for NAFLD patients with normal BMI, as well as provide an early warning system for the understanding and prevention of NAFLD in non-obese patients.

METHODS

This cross-sectional study enrolled 159,959 Chinese subjects with BMI <24 kg/m2 and normal levels of low-density lipoprotein cholesterol (LDL-c). The average age was 40.21 ± 13.88 years, and males accounted for 45.7%. A total of 15,907 (9.94%) patients with NAFLD were diagnosed by ultrasonography. Biochemical indicators were measured using an automated analyzer (Abbott AxSYM). The BMI (kg/m2) was calculated from the weight (kg)/height in square meters (m2). The BMI quartile was used as the column-stratified variable to determine the baseline distribution, and logistic regression analysis was used to assess the relationship between NAFLD and its risk factors, with multiple logistic regression used to assess the relationships between BMI or TG and NAFLD and multivariate linear regression used to analyze the association between BMI and TG, while mediation analysis was used to assess the mediation effect of TG.

RESULTS

After adjustment of all covariates, the odds ratios were 1.788 (95% CI: 1.749-1.829; p < 0.00001) and 1.491 (95% CI: 1.451-1.532; p < 0.00001) for the association between BMI and TG with NAFLD incidence. The multivariate linear regression coefficient of BMI and TG was β = 0.027 (95% CI: 0.023-0.030; p < 0.00001). Mediation analysis showed that BMI contributed to 10.81% of lean NAFLD with a mediation effect of 2.98%.

CONCLUSION

In a Chinese population with BMI <24 kg/m2 and normal LDL-c levels, BMI and TG were found to be independent predictors of NAFLD. The direct effect of BMI on non-obese NAFLD was 10.41%. The TG level was found to partially mediate the association.

Cellular and molecular effects of fipronil in lipid metabolism of HepG2 and its possible connection to non-alcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is a global public health problem that affects more than a quarter of the population. The development of this disease is correlated with metabolic dysfunctions that lead to lipid accumulation in the liver. Pesticides are one of etiologies that support NAFLD establishment. Therefore, the effects of the insecticide fipronil on the lipid metabolism of the human hepatic cell line, HepG2, was investigated, considering its widespread use in field crops and even to control domestic pests. To address the goals of the study, biochemical, cellular, and molecular analyses of different concentrations of fipronil in cell cultures were investigated, after 24 h of incubation. Relevant metabolites such as triglycerides, glucose levels, β-oxidation processes, and gene expression of relevant elements correlated with lipid and metabolism of xenobiotics were investigated. The results suggested that at 20 μM, the pesticide increased the accumulation of triglycerides and neutral lipids by reducing fatty acid oxidation and increasing de novo lipogenesis. In addition, changes were observed in genes that control oxidative stress and the xenobiotic metabolism. Together, the results suggest that the metabolic changes caused by the insecticide fipronil may be deleterious if persistent, favoring the establishment of hepatic steatosis.

Global, regional, and national burden of liver cancer due to non-alcoholic steatohepatitis, 1990-2019: a decomposition and age-period-cohort analysis

BACKGROUND

Identifying past temporal trends in non-alcoholic steatohepatitis (NASH)-associated liver cancer (NALC) can increase public awareness of the disease and facilitate future policy development.

METHODS

Annual deaths and age-standardized death rates (ASDR) for NALC from 1990 to 2019 were collected from the Global Burden of Disease (GBD) 2019 study. The long-term trend and the critical inflection of mortality of NALC were detected by Joinpoint analysis. Age-period-cohort analysis was employed to evaluate the effects of age, period, and cohort. Last, decomposition analysis was used to reveal the aging and population growth effects for NALC burden.

RESULTS

Between 1990 and 2019, the ASDR of NALC witnessed an overall declining trend on a global scale, with a decrease in females and a stable trend in males. However, the global ASDR demonstrated a significant upward trend from 2010 to 2019. Southern sub-Saharan Africa and Southeast Asia have the highest NALC burdens, while high socio-demographic index (SDI) region experienced the fastest escalation of NALC burdens over 30 years. The decomposition analysis revealed that population growth and aging were the primary catalysts behind the increase in global NALC deaths. Age-period-cohort analyses showed that NALC mortality declined the fastest among females aged 40-45 years in high SDI region, accompanied by a deteriorating period effect trend during the period of 2010-2019.

CONCLUSION

The global absolute deaths and ASDR of NALC have witnessed a rise in the past decade, with populations exhibiting considerable disparities based on sex, age, and region. Population growth, aging, and metabolism-related factors were the main factors behind the increase in global NALC deaths.

Coagulation Dysfunctions in Non-Alcoholic Fatty Liver Disease-Oxidative Stress and Inflammation Relevance

Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases. Its incidence is progressively rising and it is possibly becoming a worldwide epidemic. NAFLD encompasses a spectrum of diseases accounting for the chronic accumulation of fat within the hepatocytes due to various causes, excluding excessive alcohol consumption. In this study, we aimed to focus on finding evidence regarding the implications of oxidative stress and inflammatory processes that form the multifaceted pathophysiological tableau in relation to thrombotic events that co-occur in NAFLD and associated chronic liver diseases. Recent evidence on the pathophysiology of NAFLD suggests that a complex pattern of multidirectional components, such as prooxidative, proinflammatory, and prothrombotic components, better explains the multiple factors that promote the mechanisms underlying the fatty acid excess and subsequent processes. As there is extensive evidence on the multi-component nature of NAFLD pathophysiology, further studies could address the complex interactions that underlie the development and progression of the disease. Therefore, this study aimed to describe possible pathophysiological mechanisms connecting the molecular impairments with the various clinical manifestations, focusing especially on the interactions among oxidative stress, inflammation, and coagulation dysfunctions. Thus, we described the possible bidirectional modulation among coagulation homeostasis, oxidative stress, and inflammation that occurs in the various stages of NAFLD.

Food Network Analysis in Non-Obese Patients with or without Steatosis

BACKGROUND

Steatosis is the most common liver disease worldwide and the leading cause of liver-associated morbidity and mortality. The aim of this study was to explore the differences in blood parameters and dietary habits in non-obese patients with and without steatosis.

METHODS

The present study included 987 participants with BMI < 30, assessed in the fourth recall of the MICOL study. Patients were divided by steatosis grade, and a validated food frequency questionnaire (FFQ) with 28 food groups was administered.

RESULTS

The prevalence of non-obese participants with steatosis was 42.86%. Overall, the results indicated many statistically significant blood parameters and dietary habits. Analysis of dietary habits revealed that non-obese people with or without steatosis had similar dietary habits, although higher daily amounts of red meat, processed meat, ready meals, and alcohol were recorded in participants with liver disease (p < 0.05).

CONCLUSIONS

Many differences were found in non-obese people with and without steatosis, but in light of a network analysis, the two groups demonstrated similar dietary habits, proving that pathophysiological, genetic, and hormonal patterns are probably the basis of their liver status, regardless of weight. Future genetic analyses will be performed to analyze the expression of genes involved in the development of steatosis in our cohort.

Non-alcoholic fatty liver disease is associated with an increased risk of type 2 diabetes

OBJECTIVE

Non-alcoholic fatty liver disease (NAFLD) has become the most common liver disease worldwide and represents the leading cause of liver-related morbidity and mortality. Its all-cause mortality is often driven by co-existing metabolic diseases such as type 2 diabetes (T2DM), which share many pathophysiological characteristics. The risk of developing T2DM among NAFLD patients in Germany is only poorly described.

METHODS

A cohort of 17 245 NAFLD patients and a propensity score-matched cohort of equal size were identified from the Disease Analyzer database (IQVIA) between 2005 and 2020. The incidence of T2DM was evaluated as a function of NAFLD during a 5-year study period using Cox-regression models.

RESULTS

Within 5 years of the index date, 18.8% and 11.7% of individuals with and without NAFLD were diagnosed with T2DM ( P  < 0.001). Regression analysis revealed a hazard ratio of 1.77 [95% confidence interval (CI), 1.68-1.88] for the development of T2DM among NAFLD patients. Subgroup analyses confirmed this association for all age groups (18-50, 51-60, 61-70 and >70 years), male and female patients, as well as normal weight (BMI < 25 kg/m 2 ), overweighted (BMI 25-30 kg/m 2 ) and obese (BMI > 30 kg/m 2 ) patients.

CONCLUSION

Our data revealed a significantly increased incidence of T2DM among NAFLD patients in Germany. Given the dramatically increasing global relevance of NAFLD, we believe that prevention and regular screening programs for T2DM in NAFLD patients could help to reduce its high mortality and morbidity in the future.

Metabolic dysfunction and nonalcoholic fatty liver disease risk in individuals with a normal body mass index

PURPOSE OF REVIEW

Nonalcoholic fatty liver disease (NAFLD) is strongly associated with obesity, but is also common in individuals with a normal body mass index (BMI), who also experience the hepatic inflammation, fibrosis, and decompensated cirrhosis associated with NAFLD progression. The clinical evaluation and treatment of NAFLD in this patient population are challenging for the gastroenterologist. A better understanding of the epidemiology, natural history, and outcomes of NAFLD in individuals with normal BMI is emerging. This review examines the relationship between metabolic dysfunction and clinical characteristics associated with NAFLD in normal-weight individuals.

RECENT FINDINGS

Despite a more favorable metabolic profile, normal-weight NAFLD patients exhibit metabolic dysfunction. Visceral adiposity may be a critical risk factor for NAFLD in normal-weight individuals, and waist circumference may be better than BMI for assessing metabolic risk in these patients. Although screening for NAFLD is not presently recommended, recent guidelines may assist clinicians in the diagnosis, staging, and management of NAFLD in individuals with a normal BMI.

SUMMARY

Individuals with a normal BMI likely develop NAFLD as a result of different etiologies. Subclinical metabolic dysfunction may be a key component of NAFLD in these patients, and efforts to better understand this relationship in this patient population are needed.

Risk Scores for Prediction of Major Cardiovascular Events in Non-Alcoholic Fatty Liver Disease: A No Man's Land?

Over the past 100 years, cardiovascular disease (CVD) has become a leading cause of mortality and morbidity in developed countries, and similar trends have occurred for chronic liver disease. Subsequent research also indicated that people with non-alcoholic fatty liver disease (NAFLD) had a twofold increased risk of CV events and that this risk was doubled in those with liver fibrosis. However, no validated CVD risk score specific for NAFLD patients has yet been validated, as traditional risk scores tend to underestimate the CV risk in NAFLD patients. From a practical perspective, identifying NAFLD patients and assessing severity of liver fibrosis when concurrent atherosclerotic risk factors are already established may serve as an important criterion in new CV risk scores. The current review aims to assess current risk scores and their utility for the prediction of CV events among patients with NAFLD.

Non-alcoholic fatty liver disease: Definition and subtypes

Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases worldwide, with a global prevalence of approximately 30%. However, the prevalence of NAFLD has been variously reported depending on the comorbidities. The rising prevalence of obesity in both the adult and pediatric populations is projected to consequently continue increasing NAFLD prevalence. It is a major cause of chronic liver disease worldwide, including cirrhosis and hepatocellular carcinoma (HCC). NAFLD has a variety of clinical phenotypes and heterogeneity due to the complexity of pathogenesis and clinical conditions of its occurrence, resulting in various clinical prognoses. In this article, we briefly described the basic definition of NAFLD and classified the subtypes based on current knowledge in this field.

Diet-induced gut dysbiosis and inflammation: Key drivers of obesity-driven NASH

Sucrose, the primary circulating sugar in plants, contains equal amounts of fructose and glucose. The latter is the predominant circulating sugar in animals and thus the primary fuel source for various tissue and cell types in the body. Chronic excessive energy intake has, however, emerged as a major driver of obesity and associated pathologies including nonalcoholic fatty liver diseases (NAFLD) and the more severe nonalcoholic steatohepatitis (NASH). Consumption of a high-caloric, western-style diet induces gut dysbiosis and inflammation resulting in leaky gut. Translocation of gut-derived bacterial content promotes hepatic inflammation and ER stress, and when either or both of these are combined with steatosis, it can cause NASH. Here, we review the metabolic links between diet-induced changes in the gut and NASH. Furthermore, therapeutic interventions for the treatment of obesity and liver metabolic diseases are also discussed with a focus on restoring the gut-liver axis.

Gut mycobiome dysbiosis contributes to the development of hypertension and its response to immunoglobulin light chains

Objectives

Human gut microbiome has gained great attention for its proposed roles in the development of hypertension. The fungal microbiome in the human gut (i.e. the mycobiome) is beginning to gain recognition as a fundamental part of our microbiome. However, the existing knowledge of human mycobiome has never revealed the association between gut mycobiome and hypertension. It is known that inflammation and immunity contribute to human hypertension. Here, we sought to investigate whether gut mycobiome could predict the development of hypertension and its association with immunoglobulin light chains.

Methods and materials

Participants were classified into three cohorts: prehypertension (pre-HTN), hypertension (HTN), and normal-tension (NT) based on their blood pressure. Fresh samples were collected, and the ITS transcribed spacer ribosomal RNA gene sequence was performed. An immunoturbidimetric test was used to examine the serum levels of immunological light chains.

Results

Subjects in both of the states of pre-HTN and HTN had different fungal microbiome community compared to the NT group (FDR<0.05). Slightly higher levels of fungal richness and diversity were observed in the groups of pre-HTN and HTN. The relative abundance of Malassezia increased in the HTN group compared to that in the NT group, and the relative abundance of Mortierella enriched in the NT group. For the pre-HTN group, the relative abundance of Malassezia was positively associated with serum the concentration of light chain (LC) κ (r=0.510, P=0.044); for the HTN group, the relative abundance of Mortierella was positively associated with the serum concentration of LC κ (P<0.05), the relative abundance of Malassezia was positively associated with both the serum concentrations of LC κ and LC λ (r>0.30, P<0.05).

Conclusions

Our present study demonstrated that gut fungal dysbiosis occurred in the state of prehypertension, and fungal dysbiosis can predict the dysregulation of serum light chains in hypertension patients. Further study on modulating gut fungal community should be focused on balancing the immunological features in hypertension.

Changes in the global, regional, and national burdens of NAFLD from 1990 to 2019: A systematic analysis of the global burden of disease study 2019

Background

Understanding the burdens and trends of non-alcoholic fatty liver disease (NAFLD) is necessary for developing effective intervention strategies. In this study, Global Burden of Disease (GBD) 2019 study data were extracted and analyzed to elucidate trends of NAFLD.

Methods

The prevalence, incidence, disability-adjusted life year (DALY), and death rates of NAFLD in geographic populations worldwide from 1990 to 2019 were extracted from the GBD 2019 study data. The global temporal trend of NAFLD from 1990 to 2019 was evaluated using estimated annual percentage changes (EAPCs) and age-standardized rates.

Results

Globally, between 1999 and 2019, the age-standardized prevalence rate of NAFLD increased, with EAPCs of 0.77 [95% CI (0.69, 0.85)], whereas the DALY and Death rates decreased, with EAPCs of -0.82 [95% CI (-0.92, -0.71)], and -0.67 [95% CI (-0.76, -0.58)], respectively. Geographically, the age-standardized prevalence rate showed the most serious upward trend in high-income North America with an EAPC of 0.98 [95% CI (0.95, 1.02)], and the age-standardized incidence rate showed an upward trend in Central Asia with an EAPC of 3.17 [95% CI (2.2, 2.49)]. The most significant upward trend of DALY and death rates appeared in Eastern Europe, with EAPCs of 4.06 [95% CI (3.31, 4.82)], and 3.36 [95% CI (2.77, 3.96)], respectively. At the country level, the age-standardized rates showed an upward trend in Armenia, Belarus, and Republic of Korea. Regarding age groups, the percentage change of prevalence was the highest in the 40 to 44 group [0.29 (0.26, 0.34)] from 1990 to 2019; the percentage change of incidence was the highest in the 85 to 89 group [0.46 (0.12, 0.71)] from 1990 to 2019; the percentage change of DALY was the highest in the 80 to 84 group [0.25 (0.11, 0.39)] from 1990 to 2019; and the percentage change of death rate was the highest in the 15 to 19 group [0.36 (0.17, 0.60)] from 1990 to 2019. The percentage change of prevalence of liver cancer due to NASH was the highest in the group of 85 to 89, whereas those of incidence, DALY, and death were the highest in the group above 95 from 1990 to 2019. Regarding the sociodemographic index (SDI), the highest age-standardized prevalence, incidence, and Death rates of NAFLD occurred in middle-SDI countries, and the highest DALY rates of NAFLD occurred in low-SDI countries.

Conclusion

Global NAFLD burdens have increased since 1990. Our findings provide a reference for policymakers to reduce the burden of NAFLD, especially in middle and low-SDI countries.

Predictive Risk Factors of Nonalcoholic Fatty Liver Disease in a Lean Chinese Population

BACKGROUND

Although nonalcoholic fatty liver disease (NAFLD) is related to obesity, it may also affect lean individuals. Recent data suggest that lean NAFLD patients can develop the whole spectrum of NASH. However, the NAFLD predictive model for lean populations remains lacking.

METHODS

A total of 5037 lean individuals were included in this study, and the data were separated for training and validation. The logistic regression method was used, and a nomogram, a type of prediction model, was constructed according to the logistic regression analysis and the significant clinical factors. The performance of this model was evaluated based on its discrimination, calibration, and clinical utility.

RESULTS

The individuals were divided into the training (n = 4068) or validation (n = 969) cohorts at a ratio of 8 to 2. The overall prevalence of NAFLD in the lean cohort was 6.43%. The nomogram was constructed based on seven predictors: alanine aminotransferase, total cholesterol, triglycerides, low-density lipoprotein cholesterol, creatinine, uric acid, and hemoglobin A1C. The model based on these factors showed good predictive accuracy in the training set and in the internal validation set, with areas under the curve (AUCs) of 0.870 and 0.887, respectively. The calibration curves and decision curve analysis (DCA) displayed good clinical utility.

CONCLUSION

the nomogram model provides a simple and reliable ability to predict the risk of NAFLD in lean subjects. The model can predict lean NAFLD and can help physicians screen and identify lean subjects at a high risk of NAFLD.