Active smoking, passive smoking, and risk of nonalcoholic fatty liver disease (NAFLD): a population-based study in China

Association of Life's Essential 8 with metabolic dysfunction-associated steatotic liver disease (MASLD), a cross-sectional study from the NHANES 2003-2018

There is limited research on the relationship between Life's Essential 8 (LE8) score and metabolic dysfunction-associated steatotic liver disease (MASLD). Our aim is to investigate the relationship between overall lifestyle assessed by LE-8 score and MASLD in a nationally representative sample. We employed the LE8 score to comprehensively evaluate cardiovascular health, the assessment of MASLD primarily utilized the Fatty Liver Index. The weighted logistic regression models, restrictive cubic splines (RCS), subgroup analyses and the weighted quantile sum (WQS) regression were used to evaluate the relationship between the cardiovascular health and MASLD. Logistic regression models revealed that higher LE8 scores were associated with lower odds of having MASLD. The RCS revealed a significant nonlinear dose-response relationship between LE8 scores and MASLD. The WQS regression model indicated that blood glucose contributed the most to the risk of MASLD. The subgroup analysis indicates that there are significant differences in this association across age, educational level, and poverty income ratio. Our study suggests that an inverse correlation between LE8 and the risk of MASLD. Our findings underscore the utility of the LE8 algorithm in MASLD risk assessment and provide support for MASLD prevention through the promotion of healthy lifestyles.

Expert panel opinion on adult pneumococcal vaccination in the post-COVID era (NAP- EXPO Recommendations-2024)

INTRODUCTION

Pneumococcal diseases pose a significant public health concern in India, with substantial morbidity and mortality, with the elderly and those with coexisting medical conditions being most at risk. Pneumococcus was also seen to be one of the main reasons for co-infection, pneumonia and complications in COVID. Current guidelines recommend vaccination for specific adult populations, but there is a lack of uniformity and guidance on risk stratification, prioritisation and optimal timing.

METHODS

Nation Against Pneumococcal Infections - Expert Panel Opinion (NAP-EXPO) is a panel convened to review and update recommendations for adult pneumococcal vaccination in India. The panel of 23 experts from various medical specialties engaged in discussions and evidence-based reviews, discussed appropriate age for vaccination, risk stratification for COPD and asthma patients, vaccination strategies for post-COVID patients, smokers and diabetics, as well as methods to improve vaccine awareness and uptake.

OUTCOME

The NAP-EXPO recommends the following for adults: All healthy individuals 60 years of age and above should receive the pneumococcal vaccine; all COPD patients, regardless of severity, high-risk asthma patients, post-COVID cases with lung fibrosis or significant lung damage, should be vaccinated with the pneumococcal vaccine; all current smokers and passive smokers should be educated and offered the pneumococcal vaccine, regardless of their age or health condition; all diabetic individuals should receive the pneumococcal vaccine, irrespective of their diabetes control. Strategies to improve vaccine awareness and uptake should involve general practitioners (GPs), primary health physicians (PHPs) and physicians treating patients at high risk of pneumococcal disease. Advocacy campaigns should involve media, including social media platforms.

CONCLUSION

These recommendations aim to enhance pneumococcal vaccination coverage among high-risk populations in India in order to ensure a reduction in the burden of pneumococcal diseases, in the post-COVID era. There is a need to create more evidence and data to support the recommendations that the vaccine will be useful to a wider range of populations, as suggested in our consensus.

Association Between Secondhand Smoke Exposure and Nonalcoholic Fatty Liver Disease in the General U.S. Adult Nonsmoker Population

INTRODUCTION

Smoking is a cause of nonalcoholic fatty liver disease (NAFLD), but the dose-response relationship between secondhand smoke exposure (SHS) and NAFLD is unclear. This study sought to determine the relationship between SHS and NAFLD risk among adult nonsmokers in the United States.

AIMS AND METHODS

Data from 7412 adult nonsmokers aged ≥20 years who participated in the National Health and Nutrition Examination Survey (NHANES) between 2007 and 2016 were used in this study. SHS was defined as a nonsmoker with a serum cotinine concentration of 0.05-10.00 ng/mL. NAFLD was identified using the U.S. fatty liver index (USFLI), hepatic steatosis index (HSI), and fatty liver index (FLI). Weighted multivariable logistic regression and restricted cubic spline models were applied to evaluate the relationship between SHS and NAFLD risk.

RESULTS

The participants had a weighted mean age of 49.2 years, and 55.5% were female. SHS was associated with NAFLD (odds ratio [OR] 1.22; 95% confidence interval CI: 1.05 to 1.42), showing a linear dose-response relationship (natural log of cotinine level: OR 1.10, 95% CI: 1.05 to 1.17). Sensitivity analyses using different NAFLD definitions (HSI: OR 1.21, 95% CI: 1.01 to 1.46; FLI: OR 1.26, 95% CI: 1.06 to 1.49), excluding participants taking hepatotoxic drugs, and propensity score-adjusted analysis yielded similar results. The association between SHS and NAFLD was consistent in analyses stratified by age, sex, and race/ethnicity.

CONCLUSIONS

Among this nationally representative sample of U.S. adults, SHS had a linear dose-response relationship with the risk of NAFLD, suggesting that measures to lower SHS might lower NAFLD risk.

IMPLICATIONS

This study assessed the association between secondhand smoke exposure and the risk of nonalcoholic fatty liver disease (NAFLD) using data from 7412 adult nonsmokers aged 20 years or older who participated in the United States NHANES between 2007 and 2016. Secondhand smoke exposure was measured using serum cotinine levels. Three different noninvasive indexes were used to measure NAFLD. Secondhand smoke exposure was associated with an increased risk of NAFLD, with a linear dose-response relationship. The results of sensitivity analyses and subgroup analyses were consistent.

Association with the plasma atherogenic index with hepatic steatosis and fibrosis in the US population

Plasma atherogenic index (AIP) reflects a novel intricate biochemical indicator of lipids' metabolism. The involvement of lipid metabolism for pathogenesis concerning nonalcoholic fatty liver disease (NAFLD) has been established. However, the precise association across AIP and hepatic steatosis and fibrosis remains unclear. This present investigation explored the potential correlation across AIP, hepatic steatosis and fibrosis. Data were acquired through National Health and Nutrition Examination Survey (NHANES) from 2017 to 2020. Hepatic steatosis was detected through the controlled attenuation parameter (CAP), while hepatic fibrosis was examined via liver stiffness measurement (LSM). The study employed multiple linear, Fitted smoothed curves and subgroup analyses were used for investigating relationships between the AIP, CAP, and LSM. The study recruited 6239 participants. In multivariate linear regression analysis, findings indicated a remarkable correlation between AIP and exacerbated NAFLD risk [odds ratio (95% confidence interval), 1.17 (1.12, 1.21)]. Analysis further revealed a positive link across AIP and hepatic steatosis, as indicated through the CAP [β (95% CI), 4.07 (3.32, 4.82)]. Tests for non-linearity, revealed a non-linear correlation between AIP and CAP (inflection point = 0.22). Subgroup analyses assessed the consistency of the link across AIP and CAP, indicating that the association remained comparable across all subgroups. Following the adjustment for all relevant variables, the linear regression analysis revealed a lack of statistical significance across the AIP and hepatic fibrosis. [LSM, β (95% CI), -0.39 (-1.06, 0.28), P = .2501]. Smooth-fitting curves examined the link across AIP and LSM and showed a U-shaped pattern, indicating their positive correlation with AIP less than 0.48. However, no significant correlation was observed with AIP more than 0.48. This study highlighted a substantial positive relationship across AIP and hepatic steatosis, as measured through CAP, and suggests that it may be used as an efficient and rapid measure for clinical prediction of hepatic steatosis.

Impact of smoking cessation on non-alcoholic fatty liver disease prevalence: a systematic review and meta-analysis

OBJECTIVES

The negative effects of smoking on numerous cardiovascular and metabolic diseases have been widely acknowledged. However, the potential effect of smoking cessation is relatively unelucidated. The objective of this study is to explore whether the prevalence of non-alcoholic fatty liver disease (NAFLD) in former smokers differs from the prevalence in current smokers.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Four databases, that is, PubMed, Web of Science, Journal@Ovid and Scopus were searched from inception to 31 January 2023.

ELIGIBILITY CRITERIA

Population-based cross-sectional studies, including the baseline data of cohort studies with identified NAFLD diagnostic methods, and smoking status (current smoker or former smoker) of participants were included.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently extracted the data including cigarette smoking status, country/region of studies, NAFLD diagnostic methods, sex, the average age and body mass index (BMI) of NAFLD participants and assessed the risk of bias with Agency for Healthcare Research and Quality (AHRQ) methodology checklist. Risk ratio (RR) of NAFLD prevalence in former smokers was pooled using the random-effects model.

RESULTS

28 studies involving 4 465 862 participants were included. Compared with current smokers, the RR of overall NAFLD prevalence in former smokers was 1.13 (95% CI: 1.08 to 1.19, prediction interval: 0.92-1.39). This result persisted after adjustment for diagnostic methods, country/region, sex, age and BMI. Sensitivity analysis and risk of bias assessment indicated a stable conclusion.

CONCLUSIONS

NAFLD prevalence in former smokers was at least not lower than that in current smokers and was partially related to increased BMI after smoking cessation, indicating that smoking cessation was possibly not a protective factor against NAFLD. Although the meta-analysis based on cross-sectional studies cannot conclude the causal relationships between smoking cessation and NAFLD onset, the potential onset of NAFLD associated with smoking cessation should be highlighted.

PROSPERO REGISTRATION NUMBER

CRD42023394944.

Hepatocyte CHRNA4 mediates the MASH-promotive effects of immune cell-produced acetylcholine and smoking exposure in mice and humans

Metabolic dysfunction-associated steatohepatitis (MASH) is a leading risk factor for liver cirrhosis and hepatocellular carcinoma. Here, we report that CHRNA4, a subunit of nicotinic acetylcholine receptors (nAChRs), is an accelerator of MASH progression. CHRNA4 also mediates the MASH-promotive effects induced by smoking. Chrna4 was expressed specifically in hepatocytes and exhibited increased levels in mice and patients with MASH. Elevated CHRNA4 levels were positively correlated with MASH severity. We further revealed that during MASH development, acetylcholine released from immune cells or nicotine derived from smoking functioned as an agonist to activate hepatocyte-intrinsic CHRNA4, inducing calcium influx and activation of inflammatory signaling. The communication between immune cells and hepatocytes via the acetylcholine-CHRNA4 axis led to the production of a variety of cytokines, eliciting inflammation in liver and promoting the pathogenesis of MASH. Genetic and pharmacological inhibition of CHRNA4 protected mice from diet-induced MASH. Targeting CHRNA4 might be a promising strategy for MASH therapeutics.

Blood manganese and non-alcoholic fatty liver disease in a high manganese exposure area in China

BACKGROUND AND AIMS

Manganese (Mn) deficiency and intoxication may affect nonalcoholic fatty liver disease (NAFLD) risk differently. We aimed to explore the association between blood Mn and NAFLD in an area with high Mn exposure in drinking water.

METHODS

We conducted a case-control study among 1407 patients with NAFLD and 1774 sex- and age-matched healthy controls in a physical examination population in Zhoushan hospital, Zhejiang province in China. We used the restricted cubic splines method to investigate the dose-response relationship. Logistic regression models were applied to determine the risk of NAFLD, and severity of NAFLD.

RESULTS

The blood Mn concentration was higher in the NAFLD group than in the control group in women (16.1 ± 6.2 μg/L vs. 14.7 ± 6.4 μg/L, P = 0.022) and men (14.5 ± 6.3 μg/L vs. 13.6 ± 6.8 μg/L, P < 0.001). We found an inverted L shape relationship between blood Mn and NAFLD in both women and men. Compared to the lowest quartile, the adjusted odds ratio (OR) and 95% confidence interval (CI) of NAFLD for the highest quartile group was 1.646(1.222,2.217), 1.494(1.082,2.061), and 3.146(1.285,7.701) for the total population, men, and women. The positive relationship was only observed in those with fibrosis-4 score < 1.30 and normal alanine transaminase. Stratified analysis showed an interaction between smoking (P = 0.073), alcohol drinking (P = 0.013), and Mn, with a more prominent effect on the NAFLD in the never-smokers (OR = 2.153, 95% CI 1.408-3.290) and drinkers (OR = 2.596, 95% CI 1.608-4.191).

CONCLUSION

Higher blood Mn is associated with an elevated NAFLD risk in the high Mn exposure areas, especially in nonsmokers and drinkers. Further studies are needed to verify this result in the areas with high Mn exposure.

Gender Differences in the Risk for Incident Non-Alcoholic Fatty Liver Disease According to the Transition of Abdominal Obesity Status: A 16-Year Cohort Study

Waist circumference (WC) is an important predictor of long-term adverse outcomes. We aimed at assessing the correlation between abdominal obesity (AO) patterns and non-alcoholic fatty liver disease (NAFLD). Data from 4467 adults aged 40-69 years and without NAFLD who participated in the Korean Genome and Epidemiology Study were analyzed. Participants were classified according to two-year WC pattern into four groups: persistent lean WC, improved AO, progressed to AO, and persistent AO. NAFLD was defined as NAFLD-liver fat score >-0.640. Multiple Cox proportional hazards regression analysis revealed that the fully adjusted hazard ratio (HR) (95% confidence intervals (CIs)) for NAFLD in persistent AO, progressed to AO, and improved AO groups compared to the persistent lean WC group was 1.33 (1.13-1.57), 1.73 (1.48-2.02), and 1.06 (0.84-1.33), respectively. Women in persistent AO or progressed to AO groups had significantly higher risk for NAFLD than those in persistent lean WC or improved AO groups. Men who had progressed to an AO event over two years had significantly higher risk for NAFLD than those without any AO event over two years. Maintaining lean WC and improving AO would be successful strategies for preventing NAFLD in women, while maintaining lean WC would be more effective in men.

Adherence to oxidative balance scores and lower odds of non-alcoholic fatty liver disease: a case-control study

Evidence has also shown that oxidative stress and systemic inflammation, or in other words, disruption of the oxidant and antioxidant balance, can play an important role in the initiation or progression of NAFLD. The purpose of this study was to investigate the associations between the oxidative balance scores (OBS) and the risk of NAFLD. 552 healthy and 340 patients adult over the age of 18 with NAFLD participated in this case-control research. A validated 168-item quantitative food frequency questionnaire (FFQ) and indicators of physical activity, obesity, and smoking status were used to assess OBS score. The connection between OBS and NAFLD was discovered using binary logistic regression. The mean (± SD) age and (body mass index) BMI of the study population was 40.22 ± 9.79 years and 29.06 ± 3.92 kg/m², respectively. The mean ± SD of OBS was 41.48 ± 5.23. After adjustment for potential confounders, higher scores of adherence to the OBS conferred a protection for the presence of NAFLD (odds ratio [OR]: 0.29; 95% confidence interval [CI]: 0.15-0.49; P for trend < 0.001). The findings of the present study indicate an approximately 80% reduction in the odds of developing NAFLD with higher OBS adherence in the overall population. However, prospective studies are needed to further investigate this association.

Risk Factors of Non-alcoholic Fatty Liver Disease in the Iranian Adult Population: A Systematic Review and Meta-analysis

Context: Non-alcoholic fatty liver disease (NAFLD) is progressing considerably worldwide. Identifying the risk factors of NAFLD is a critical step in preventing its progression. Methods: In November 2022, two independent researchers studied seven databases, including PubMed, ISI/WoS, ProQuest, Scopus, SID, Magiran, and Google Scholar, and reference list of relevant articles, searching studies that assessed NAFLD risk factors in the Iranian adult population. Heterogeneity between studies was assessed by Cochran’s test and its composition using I2 statistics. A random-effects model was used when heterogeneity was observed; otherwise, a fixed-effects model was applied. Egger’s regression test and Trim-and-Fill analysis were used to assess publication bias. Comprehensive Meta-analysis software (version 3) was used for the analyses of the present study. Results: The results of this study showed significant associations between NAFLD with age [n = 15, odds ratio (OR) = 2.12, 95% CI: 1.79 - 2.51], body mass index (n = 46, OR = 5.00, 95% CI: 3.34 - 7.49), waist circumference (n = 20, OR = 6.37, 95% CI: 3.25 - 12.48), waist-to-hip ratio (n = 17, OR = 4.72, 95% CI: 3.93 - 5.66), total cholesterol (n = 39, OR = 1.80, 95% CI: 1.52 - 2.13), high-density lipoprotein (n = 37, OR = 0.53, 95% CI: 0.44 - 0.65), low-density lipoprotein (n = 31, OR = 1.68, 95% CI: 1.38 - 2.05), triglyceride (n = 31, OR = 3.21, 95% CI: 2.67 - 3.87), alanine aminotransferase (n = 26, OR = 4.06, 95% CI: 2.94 - 5.62), aspartate aminotransferase (n = 27, OR = 2.16, 95% CI: 1.50 - 3.12), hypertension (n = 13, OR = 2.53, 95% CI: 2.32 - 2.77), systolic blood pressure (n = 13, OR = 1.83, 95% CI: 1.53 - 2.18), diastolic blood pressure (n = 14, OR = 1.80, 95% CI: 1.48 - 2.20), fasting blood sugar (n = 31,OR = 2.91, 95% CI: 2.11- 4.01), homeostatic model assessment for insulin resistance (n = 5, OR = 1.92, 95% CI: 1.48 - 2.59), diabetes mellitus (n = 15, OR = 3.04, 95% CI: 2.46 - 3.75), metabolic syndrome (n = 10, OR = 3.56, 95% CI: 2.79 - 4.55), and physical activity (n = 11, OR = 0.32, 95% CI: 0.24 - 0.43) (P < 0.05). Conclusions: In conclusion, several factors are significantly associated with NAFLD. However, anthropometric indices had the strongest relationship with NAFLD in the Iranian adult population.

Burden of liver complications related to non-alcoholic fatty liver disease in China from 2005 to 2019: Observations from the Global Burden of Disease Study, 2019

AIM

To assess the burden of liver complications related to non-alcoholic fatty liver disease (LC-NAFLD) from 2005 to 2019 in China.

MATERIALS AND METHODS

We used data from the Global Burden of Disease, Injuries, and Risk Factors Study, 2019, to present contemporary and varying profiles of China's LC-NAFLD burden. The Joinpoint Regression model and Gaussian process regression were, respectively, used to estimate the annual percentage change in prevalence rates and disability-adjusted life-year (DALY) rates, and the relationship between the sociodemographic index (SDI) and age-standardized rates of LC-NAFLD.

RESULTS

In 2019, China had 293.42 million (95% uncertainty interval [UI]: 263.69-328.44) LC-NAFLD cases with a prevalence rate and DALYs of 20.63 (95% UI: 23.09-18.54) per 1000 people and 591.03 thousand (95% UI: 451.25-737.33), respectively. North China had the highest prevalence but the lowest DALYs of LC-NAFLD, whereas Southwest China had the lowest prevalence but the highest DALYs. LC-NAFLD were more common in men than in women (male: female ratio, 1.27) in 2019. From 2005 to 2019, the prevalence of NAFLD cases increased by 68.32% (from 174.32 million in 2005 to 293.42 million in 2019), mainly because of an age-specific prevalence rate increase.

CONCLUSION

The LC-NAFLD burden in China is substantial and has increased markedly over the past 15 years. Effective measures for low SDI regions and men are needed to address the rapidly increasing NAFLD burden.

Association between smoking cessation and non-alcoholic fatty liver disease using NAFLD liver fat score

Background

Smoking is well known to be associated with a higher prevalence and incidence of liver diseases such as advanced fibrosis. However, the impact of smoking on developing nonalcoholic fatty liver disease remains controversial, and clinical data on this is limited. Therefore, this study aimed to investigate the association between smoking history and nonalcoholic fatty liver disease (NAFLD).

Methods

Data from the Korea National Health and Nutrition Examination Survey 2019-2020 were used for the analysis. NAFLD was diagnosed according to an NAFLD liver fat score of >-0.640. Smoking status was classified as into nonsmokers, ex-smokers, and current smokers. Multiple logistic regression analysis was conducted to examine the association between smoking history and NAFLD in the South Korean population.

Results

In total, 9,603 participants were enrolled in this study. The odds ratio (OR) for having NAFLD in ex-smokers and current smokers in males was 1.12 (95% confidence interval [CI]: 0.90-1.41) and 1.38 (95% CI: 1.08-1.76) compared to that in nonsmokers, respectively. The OR increased in magnitude with smoking status. Ex-smokers who ceased smoking for <10 years (OR: 1.33, 95% CI: 1.00-1.77) were more likely to have a strong correlation with NAFLD. Furthermore, NAFLD had a dose-dependent positive effect on pack-years, which was 10 to 20 (OR: 1.39, 95% CI: 1.04-1.86) and over 20 (OR: 1.51, 95% CI: 1.14-2.00).

Conclusion

This study found that smoking may contribute to NAFLD. Our study suggests cessation of smoking may help management of NAFLD.

Global burden of non-alcoholic fatty liver disease in 204 countries and territories from 1990 to 2019

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a growing epidemic linked to metabolic disease and is the most prevalent cause of chronic liver disease. We, therefore, designed the study to analyze the global and regional burden of NAFLD from 1990 to 2019.

METHODS

We collected data on NAFLD from the Global Burden of Disease study 2019, aiming to conduct a systematic assessment of the changes and trends in NAFLD in 204 countries. Secondary analysis of NAFLD was conducted using age-standardized rates (ASRs) and estimated annual percentage changes (EAPCs) to show the changing trends and development characteristics. Data statistics and visualization were executed with the R program.

RESULTS

Globally, incidence, deaths and disability-adjusted life years (DALYs) of NAFLD all showed an upward trend. Between 1990 and 2019, the incidence of NAFLD increased by 95.4%, from 88,177 to 172,330 cases. Meanwhile, the ASIR of the middle SDI region had the highest increase, followed by the low-middle SDI region. Of all countries, the most incident cases were in China, which accounted for approximately 23.6% of NAFLD. China was also the country with the largest cases of deaths and DALYs. And behavioral risk, metabolic factors, smoking and high fasting plasma glucose were the critical risk factors associated with the mortality and DALYs of NAFLD.

CONCLUSION

NAFLD has become a considerable health burden in many countries. Therefore, we should control the risk factors of NAFLD and take corresponding measures to achieve its early prevention and treatment.

Association between smoking and non-alcoholic fatty liver disease in Southeast Asia

An estimated 8 million people die each year from tobacco smoking, with an increasing frequency recently being observed in Southeast Asian countries, which is a preventable risk factor for mortality. NAFLD, fibrosis, advancement of hepatocellular carcinoma, and prognosis for those with severe liver disease are all negatively influenced. NAFLD and cigarette usage seem to be a direct link. Oxidative stress and oncogenic signals have been implicated in cancer development in animal models and human clinical trials. The elevated risk of cardiovascular disease and malignancies in those with steatohepatitis and those who have had liver transplants is exacerbated by smoking. We found that smoking cessation may increase treatment response and fibrosis regression rates, decrease hepatocellular carcinoma incidence, and improve liver transplant outcomes. In the last segment, we'll look at electronic cigarettes, a hot subject in public health right now, as well as additional repercussions of smoking.

The Triangle of Nonalcoholic Fatty Liver Disease, Metabolic Dysfunction, and Periodontitis: Analysis of the Dental, Oral, Medical and Epidemiological (DOME) Records-Based Nationwide Research

This study aimed to analyze the associations of nonalcoholic fatty liver disease (NAFLD) with dental parameters, while controlling for socio-demographics, health-related habits, and each of the metabolic syndrome (MetS) components, consequences, and related conditions among a nationally representative sample of young and middle-aged adults. To that end, we analyzed data from the dental, oral, medical epidemiological (DOME) cross-sectional records-based study that combined comprehensive socio-demographic, medical, and dental databases of a nationally representative sample of military personnel. Included were 132,529 subjects aged 18-50 who attended military dental clinics for one year. The prevalence of NAFLD in the study population was 0.7% (938/132,529). The following parameters maintained a statistically positive association with NAFLD in the multivariate analysis (from highest to lowest OR): male sex (OR = 3.91 (2.29-6.66)), hyperlipidemia (OR = 3.69 (2.75-4.95)), diabetes Type 2 (OR = 3.14 (2.21-4.46)), hypertension (OR = 1.67 (1.30-2.14)), periodontitis (OR = 1.42 (1.06-1.89)), body mass index (BMI) (OR = 1.15 (1.13-1.18)), and age (OR = 1.08 (1.06-1.09)). The multivariate analysis established a profile of the "patient vulnerable to NAFLD", including older age, male sex, and other MetS components, including diabetes type 2, hypertension, hyperlipidemia, BMI, and periodontitis. This profile aligns with the current new definition of metabolic dysfunction-associated fatty liver disease (MAFLD). We also analyzed the associations of the sum of the standard dental unit (SDU) scores of planned (SDU-P) and delivered (SDU-D) dental procedures per patient with NAFLD using receiver operating characteristic (ROC) analysis. The SDU-P (planned) score exhibited excellent discrimination for NAFLD (area under the curve (AUC) = 0.718 (0.703-0.734)). Overall, the results confirmed the hypothesis of this research, i.e., that NAFLD is associated with dental morbidity, particularly with periodontitis.

Longitudinal Associations of Risk Factors and Hepatocellular Carcinoma in Patients With Cured Hepatitis C Virus Infection

INTRODUCTION

There are limited data on the effect and evolution of risk factors for hepatocellular carcinoma (HCC) in patients with virologically cured hepatitis C virus (HCV) infection.

METHODS

We conducted a retrospective cohort study of patients with HCV who achieved sustained virological response with direct-acting antivirals from 130 Veterans Administration hospitals during 2014-2018, followed through 2021. Cox proportional hazards models were constructed at 3 landmark times (baseline and 12 and 24 months after sustained virological response) to examine associations between demographic, clinical, and behavioral factors and HCC risk, stratified by cirrhosis status.

RESULTS

Among 92,567 patients (32% cirrhosis), 3,247 cases of HCC were diagnosed during a mean follow-up of 2.5 years. In patients with cirrhosis, male sex (hazard ratios [HR]: 1.89, 1.93, and 1.99), cirrhosis duration ≥5 years (HR: 1.71, 1.79, and 1.34), varices (HR: 1.73, 1.60, and 1.56), baseline albumin (HR: 0.48, 0.47, and 0.49), and change in albumin (HR: 0.82 and 0.90) predicted HCC risk at each landmark time. HCV genotype 3, previous treatment, bilirubin, smoking, and race influenced HCC risk at baseline, but their effects attenuated over time. In patients without cirrhosis, diabetes (HR: 1.54, 1.42, and 1.47) and hypertension (HR: 1.59, 1.65, and 1.74) were associated with HCC risk at all landmark times. Changes in fibrosis-4 scores over time were associated with HCC risk both in patients with and without cirrhosis.

DISCUSSION

Risk factors for HCC were different in patients with and without cirrhosis and some also evolved during follow-up. These factors can help with risk stratification and HCC surveillance decisions in patients with cured HCV.

Effects of chemical mixtures on liver function biomarkers in the Korean adult population: thresholds and molecular mechanisms for non-alcoholic fatty liver disease involved

There is a scarcity of research on the effects of a mixture of chemicals on liver function biomarkers and non-alcoholic fatty liver disease (NAFLD) indices, including FSI, HIS, and FBI-4. Thus, we aimed to explore whether there is an association between chemical mixtures, including 26 chemicals found in blood and urine, liver function biomarkers, and non-alcoholic fatty liver disease (NAFLD) indices in Korean adults. The effects of exposure to chemical mixtures on liver function biomarkers and NAFLD indices were investigated using linear regression models, weighted quantile sum (WQS) regression, quantile g-computation (qgcomp), and Bayesian kernel machine regression (BKMR) among 3669 adults. In silico toxicogenomic data-mining, we evaluated molecular mechanisms associated with NAFLD, including pathways, diseases, genes, miRNAs, and biological processes. The linear regression models showed blood or urine Hg levels were the most important factors associated with AST, ALT, GGT, FSI, and HSI levels, and significant trends were observed for these chemical quartiles (p < 0.01). The WQS index was significantly associated with ALT, GGT, FSI, and HSI. The qgcomp index also found an association between chemicals and AST, ALT, GGT, and FSI. In the BKMR model, the overall effect of the mixture was significantly related to ALT, GGT, FSI, and HSI. In silico analysis, we found mixed chemicals interacted with the CYP1A2 gene and were associated with NAFLD. Seventy-eight percent of interactions were identified as physical interactions in the CYP1A2 gene related to NAFLD. Transcription factor regulation in adipogenesis and lipid metabolic processes are fundamental molecular mechanisms that could be influenced by NAFLD-related mixed chemicals. Cutoff thresholds for chemical exposure levels associated with liver function indicators and NAFLD indices were also reported. The strongest interactions and expression of miRNAs involved in NAFLD development were also identified.

Higher Adherence to Healthy Lifestyle Score Is Associated with Lower Odds of Non-Alcoholic Fatty Liver Disease

Growing evidence supports that individual lifestyle factors contribute to the development of non-alcoholic fatty liver disease (NAFLD) without considering the coexistence and synergistic effect of lifestyle factors. Our aim is to derive a healthy lifestyle score (HLS) and estimate its association with NAFLD. In this nationwide cross-sectional study, we derived a five-item HLS including dietary pattern, body mass index, physical activity, cigarette smoking, and sleep duration. NAFLD and clinically significant fibrosis (CSF) were assessed based on vibration-controlled transient elastography (VCTE). Liver function parameters were also tested. Multivariable logistic and linear regressions were applied to investigate the association between HLS and liver diseases. Of the 3893 participants with VCTE examination, approximately 14.1% of participants possessed zero or one healthy lifestyle, 62.5% possessed two or three healthy lifestyles, and 23.4% possessed four or five healthy lifestyles. Compared with participants with a low HLS (0−1 score), the adjusted odds ratios and 95% confidence intervals for those with a high HLS (4−5 score) were 0.25 (0.19~0.33, Ptrend < 0.001) for NAFLD and 0.30 (0.18~0.50, Ptrend < 0.001) for CSF. HLS was positively associated with albumin, total protein, and total bilirubin (all Ptrend ≤ 0.001), and was inversely associated with globulin, alanine aminotransferase, and gamma-glutamyl transaminase (all Ptrend ≤ 0.003). Higher adherence to HLS is associated with lower odds of NAFLD and CSF and may improve liver function. Strategies for the promotion of a healthy lifestyle should be considered as part of NAFLD prevention.

The impact of health status, diet and lifestyle on non-alcoholic fatty liver disease: Narrative review

Non-alcoholic fatty liver disease (NAFLD) is defined as the abnormal accumulation of triglycerides in the liver. NAFLD has a global prevalence of almost 30%, while incidence is rising with increasing levels of obesity, type 2 diabetes mellitus (T2DM) and metabolic syndrome. Nutrition plays a significant role in both the prevention and treatment of NAFLD. Therefore, the aim of this literature review is to explore the associations between dietary, lifestyle and other risk factors and the risk for developing NAFLD. Dietary patterns, lifestyle behaviours, comorbidities, or a combination of any may contribute to either the progression or prevention of NAFLD. Having diabetes, hypertension, or having obesity might increase the progression of NAFLD if not well treated and controlled. Diet influences the progression of NAFLD; following a western diet or simply a high-fat diet may contribute to the worsening of NAFLD and further progression to non-alcoholic steatohepatitis (NASH) and cirrhosis in later stages. On the other hand, the Mediterranean diet is the gold standard for both the treatment and prevention of NAFLD. Social behaviours, such as smoking, caffeine consumption and physical activity also play a role in the pathophysiology of NAFLD. Nutrition contributes significantly to the prevention or treatment of NAFLD, since this disease can be managed by diet and physical activity. However, further studies are still needed for a better understanding of the mechanisms of action. Randomized control trials are also needed to confirm findings in observational studies.

Association of the Metabolic Dysfunction-Associated Fatty Liver Disease with Serum Uric Acid-to-Creatinine Ratio

Background: No study has examined whether serum uric acid/creatinine (sUA/Cr) is associated with the newly defined metabolic-associated fatty liver disease (MAFLDs). Furthermore, studies on other factors influencing their relationship have not been conducted. Aim: To investigate the relationship between sUA/Cr and newly defined MAFLD, and to identify any factors that affect this relationship. Methods: We retrospectively reviewed the data of patients who underwent abdominal computed tomography (CT) at the Hospital Health Promotion Center. Participants were divided into the healthy (no evidence of liver disease; n = 707), MAFLD+non-heavy drinking (steatosis diagnosed by CT and drinking <140 and 70 grams/week for men and women, respectively; n = 291), and MAFLD+heavy drinking (fatty liver diagnosed by CT and drinking >140 and 70 grams/week for men and women, respectively; n = 61) groups. The relationship between sUA/Cr and MAFLD among the three groups were compared using multivariate logistic regression. Results: After adjusting for age, it was observed that when the sUA/Cr ratio increased by 1, the risk of MAFLD increased by 1.205 times the risk in the normal group. After adjusting for age, an increase by 1 in the sUA/Cr ratio increased the probability of non-heavy drinking+MAFLD and heavy drinking+MAFLD by 1.302 and 1.556 times, respectively, compared with healthy individuals. For those who smoked, the probability of heavy drinking+MAFLD was 9.901 times higher compared with healthy individuals. Conclusion: The newly defined MAFLD is related to sUA/Cr. The amount of alcohol consumption and smoking influenced the association between sUA/Cr and MAFLD.

Nonalcoholic Fatty Liver Disease and Cardiovascular Disease: a Review of Shared Cardiometabolic Risk Factors

The prevalence of nonalcoholic fatty liver disease (NAFLD) is rising. NAFLD/nonalcoholic steatohepatitis (NASH) is associated not only with hepatic morbidity and mortality but also with an increased cardiovascular risk. NAFLD and cardiovascular disease (CVD) share several risk factors, such as obesity, metabolic syndrome, hypertension, dyslipidemia, type 2 diabetes, and chronic kidney disease. This review summarizes the evidence linking cardiometabolic risk factors and NAFLD in the context of risk for CVD. The cause of NAFLD/NASH is complex, involving a range of factors from genetics to lifestyle and energy balance. Genetically driven high liver fat content does not appear to be causally associated with increased CVD risk. In contrast, metabolic dysfunction not only predisposes to liver pathology but also leads to a significantly higher CVD risk. Given that NAFLD pathophysiology is influenced by multiple factors, each patient is unique as to their risk of developing CVD and liver pathology. At the same time, the rising burden of NAFLD/NASH is closely linked with the global increase in metabolic disorders, including obesity and type 2 diabetes. Therefore, both personalized therapeutic approaches that recognize individual pathophysiology, as well as public health policies that address the root causes of cardiometabolic risk factors for NAFLD may be needed to effectively address the NAFLD/NASH epidemic.

Growth of exclusively breastfed small for gestational age term infants in the first six months of life: a prospective cohort study

BACKGROUND

Compared to their appropriate-for-gestational-age (AGA) peers, small-for-gestational-age (SGA) infants are prone to growth deficits. As the first 6 months of exclusive breastfeeding is generally recommended, it is essential to understand how this intervention might impact SGA infants' growth. This study aims to assess growth of exclusively breastfed SGA term infants in the first 6 months of life.

METHODS

A prospective cohort study was conducted on term infants born in Dr. Sardjito General Hospital and two private hospitals in Yogyakarta, Indonesia. SGA was defined as birth weight less than the 10th percentile according to Fenton criteria. Weight, length, and head circumference (HC) were measured at birth and monthly until 6 months old.

RESULTS

A total of 39 AGA and 17 SGA term infants who were exclusively breastfed in their first 6 months were included and followed. In SGA compared to AGA, birth weight, length, and HC (mean ± SD) were significantly lower (p < 0.001). During the first 6 months, the SGAs grew in weight and length in parallel with the AGAs. At sixth months of age, the weight and length (mean ± SD) of the SGAs were significantly lower compared to the AGAs (p < 0.001). However, HC (mean ± SD) of SGAs grew significantly faster than the AGAs (p < 0.005). At sixth months of age, there were no significant differences in HC between the two groups (p = 0.824).

CONCLUSIONS

In the first 6 months, exclusively breastfed SGA term infants, in contrast to weight and length, only show catch up growth in HC, leading to HC comparable to their AGA peers at the age of 6 months.

A Cross-Sectional Study of the Correlation Between the Atherogenic Index of Plasma and Nonalcoholic Fatty Liver Disease in Patients with Type 2 Diabetes

PURPOSE

The main objective of this study was to examine the possible association between the atherogenic index of plasma (AIP) and the prevalence of nonalcoholic fatty liver disease (NAFLD) in Chinese individuals with type 2 diabetes mellitus (T2DM).

PATIENTS AND METHODS

In this survey, data from 1074 patients with T2DM were retrospectively extracted. The correlations between each variable and NAFLD were determined by univariate analysis, and then, the statistically significant variables were evaluated for their association with AIP and NAFLD by multivariate regression analysis.

RESULTS

AIP levels were significantly higher in all males and females with NAFLD than those without NAFLD (p<0.001). The prevalence of NAFLD increased progressively throughout the AIP quartiles (trend P < 0.001) and accounted for possible variables in Model 3 of the multivariate logistic regression analysis (OR: 2244.984). In terms of sensitivity and specificity, the AIP index was found to be 65.0% and 90.1% accurate, respectively, with a 95% CI of 0.804-0.893. According to a stratified analysis, females, patients over the age of 56 and current nonsmokers were found to have a higher chance of developing NAFLD.

CONCLUSION

T2DM individuals with NAFLD were found to have a higher AIP index than those without NAFLD. The prevalence and progression of NAFLD in T2DM patients may be influenced by the AIP index.

Synergistic Interaction of Dietary Pattern and Concordance Lifestyle with Abnormal Liver Function among Young Adults in Taiwan: A Population-Based Longitudinal Study

While diet and lifestyle are independently implicated in the etiology of liver disease, the interaction of diet and lifestyle may be more helpful for determining the risk of liver abnormality. Thus, our study aimed to evaluate the interaction between the dietary pattern associated with liver biomarkers and lifestyle factors among Taiwanese adults with abnormal liver enzymes. A liver-associated dietary pattern, generated using reduced rank regression, was characterized by high intake of soy sauce or other dips, sugar sweetened beverages, and preserved and processed foods, but low intake of seafood, fruits, eggs, and dark-colored vegetables. In the fully adjusted model, liver-associated dietary patterns or unhealthy concordance lifestyle factors were associated with an increased risk of having liver function abnormality (OR = 1.08, 95% CI: 1.04, 1.12 and OR = 1.42, 95% CI: 1.31, 1.53, respectively). Moreover, the interaction between liver-associated dietary pattern and unhealthy concordance lifestyle factors showed more significant correlation, with an elevated risk of abnormal liver function (OR = 2.14, 95% CI: 2.02, 2.26). Therefore, our study suggests that participants who have a strong liver-associated dietary pattern along with unhealthy concordance lifestyles are likely to have increased odds of abnormal liver function.

Higher Healthy Lifestyle Score is associated with lower presence of non-alcoholic fatty liver disease in middle-aged and older Chinese adults: a community-based cross-sectional study

OBJECTIVE

Previous studies have reported inverse associations between certain healthy lifestyle factors and non-alcoholic fatty liver disease (NAFLD), but limited evidence showed the synergistic effect of those lifestyles. This study examined the relationship of a combination of lifestyles, expressed as Healthy Lifestyle Score (HLS), with NAFLD.

DESIGN

A community-based cross-sectional study. Questionnaires and body assessments were used to collect data on the six-item HLS (ranging from 0 to 6, where higher scores indicate better health). The HLS consists of non-smoking (no active or passive smoking), normal BMI (18·5-23·9 kg/m2), physical activity (moderate or vigorous physical activity ≥ 150 min/week), healthy diet pattern, good sleep (no insomnia or <6 months) and no anxiety (Self-rating Anxiety Scale < 50), one point each. NAFLD was diagnosed by ultrasonography.

SETTING

Guangzhou, China.

PARTICIPANTS

Two thousand nine hundred and eighty-one participants aged 40-75 years.

RESULTS

The overall prevalence of NAFLD was 50·8 %. After adjusting for potential covariates, HLS was associated with lower presence of NAFLD. The OR of NAFLD for subjects with higher HLS (3, 4, 5-6 v. 0-1 points) were 0·68 (95 % CI 0·51, 0·91), 0·58 (95 % CI 0·43, 0·78) and 0·35 (95 % CI 0·25, 0·51), respectively (P-values < 0·05). Among the six items, BMI and physical activity were the strongest contributors. Sensitivity analyses showed that the association was more significant after weighting the HLS. The beneficial association remained after excluding any one of the six components or replacing BMI with waist circumference.

CONCLUSIONS

Higher HLS was associated with lower presence of NAFLD, suggesting that a healthy lifestyle pattern might be beneficial to liver health.

Exposure to cigarette smoke precipitates simple hepatosteatosis to NASH in high-fat diet fed mice by inducing oxidative stress

Consumption of diet rich in fat and cigarette smoking (CS) are independent risk factors of non-alcoholic steatohepatitis (NASH), and they often occur together in some populations. The present study investigated the mechanisms of high-fat diet (HFD) and CS, individually and in combination, on the pathogenesis of NASH in mice. C57BL/6 male mice were subjected to either a low-fat chow (CH) or HFD with or without mainstream CS-exposure (4 cigarettes/day, 5 days/ week for 14 weeks). HFD alone caused hepatosteatosis (2.5-fold increase in TG content) and a significant increase in 3-nitrotyrisine (by ∼40-fold) but without an indication of liver injury, inflammation or fibrosis. CS alone in CH-fed mice increased in Tnfα expression and macrophage infiltration by 2-fold and relatively less increase in 3-nitrotyrosine (18-fold). Combination of HFD and CS precipitated hepatosteatosis to NASH reflected by exacerbated makers of liver inflammation and fibrosis which were associated with much severe liver oxidative stress (90-fold increase in 3-nitrotyrisine along with 6-fold increase in carbonylated proteins and 56% increase in lipid oxidations). Further studies were performed to administer the antioxidant tempol to CS exposed HFD mice and the results showed that the inhibition of liver oxidative stress prevented inflammatory and fibrotic changes in liver despite persisting hepatosteatosis. Our findings suggest that oxidative stress is a key mechanism underlying CS-promoted progression of simple hepatosteatosis to NASH. Targeting hepatic oxidative stress may be a viable strategy in halting the progression of metabolic associated fatty liver disease.

Relationship between childhood secondhand smoke exposure and the occurrence of hyperlipidaemia and coronary heart disease among Chinese non-smoking women: a cross-sectional study

OBJECTIVE

The objective of this study was to evaluate the influence of secondhand smoke (SHS) exposure during childhood on type 2 diabetes mellitus, hypertension, hyperlipidaemia and coronary heart disease among Chinese non-smoking women.

METHODS

In this cross-sectional study, the SHS exposure data in childhood were obtained using a questionnaire survey. Self-reported childhood SHS exposure was defined as the presence of at least one parent who smoked during childhood.

RESULTS

Of the 6522 eligible participants, 2120 Chinese women who had never smoked were assessed. The prevalence of SHS exposure in the entire population was 28.1% (596). SHS exposure during childhood was not significant for the standard risk factors of type 2 diabetes mellitus (p=0.628) and hypertension (p=0.691). However, SHS was positively associated with hyperlipidaemia (p=0.037) after adjusting for age, obesity, education status, physical activity, alcohol consumption, current SHS exposure status, diabetes mellitus and hypertension. In addition, childhood SHS increased the occurrence of coronary heart disease (p=0.045) among non-smokers after further adjusting for hyperlipidaemia.

CONCLUSION

SHS exposure during childhood is associated with prevalent hyperlipidaemia and coronary heart disease in adulthood among non-smoking Chinese women.

The Effect of Passive Smoking on Early Clinical Outcomes After Total Knee Arthroplasty Among Female Patients

PURPOSE

The aim of this study was to assess whether passive smoking affects clinical outcomes among female patients with knee osteoarthritis after being treated with total knee arthroplasty (TKA).

METHODS

The study prospectively enrolled 216 female patients who did not smoke and those patients were classified into three groups in terms of the severity of exposure to environmental tobacco smoke. A three-month follow-up was conducted to assess the physical and mental outcomes between the three groups. The physical outcomes were evaluated by the visual analogue score (VAS), range of motion (ROM), hospital for special surgery (HSS) knee score, and postoperative complications. The mental outcomes were assessed by the anxiety and depression scale (HADS) and medical outcome study short form 36 (SF-36). Subgroup analysis of patients with and without surgical site infection (SSI) was also calculated.

RESULTS

Baseline characteristics were similarly distributed between the three groups (P>0.05). Patients in the heavy passive smoking group had a higher VAS and a lower ROM score as compared with patients in the no and mild passive smoking group at discharge (P<0.01), 1 month (P<0.01), and 3 months (P<0.01) after surgery. Patients in the heavy passive smoking group also had a higher rate of HADS more than 8 at postoperative 1 month (P=0.01) and 3 months (P=0.03) and lower SF-36 summary (P<0.01) and HSS score (P<0.01) at postoperative 3 months. Forty-five postoperative complication events were observed during follow-up. Patients in the heavy passive smoking group (8.51%) had the highest SSI rate, followed by patients in the mild (1.82%) and no passive smoking group (0.88%) at discharge (P=0.02) and postoperative 1 month (P=0.03).

CONCLUSION

Passive smoking negatively affects TKA among female patients. It may trigger poor pain and functional outcomes, aggravate depression and anxiety, and deteriorate quality of life after discharge from hospital. Avoiding exposure to smoking environment may be beneficial among TKA female patients before and after surgery.

Childhood and Adulthood Passive Smoking and Nonalcoholic Fatty Liver in Midlife: A 31-year Cohort Study

INTRODUCTION

Identifying early life risk factors remains key to the prevention of nonalcoholic fatty liver (hereinafter "fatty liver") in adulthood. However, the longitudinal association of childhood passive smoking with adult fatty liver is not studied. We examined the association of childhood and adulthood passive smoking with fatty liver in midlife.

METHODS

This was a 31-year prospective cohort study of 1,315 participants. Information on childhood passive smoking (parental smoking) was collected in 1980 (aged 3-18 years) and 1983 and adulthood passive smoking in 2001, 2007, and 2011. Fatty liver was determined by ultrasound in 2011 (aged 34-49 years).

RESULTS

The prevalence of fatty liver was 16.3%. Both childhood and adulthood passive smoking were associated with higher risk of fatty liver, adjusting for potential confounders such as age, sex, childhood socioeconomic status, and adulthood physical activity and alcohol consumption (relative risk = 1.41, 95% confidence interval: 1.01-1.97 for childhood; 1.35, 1.01-1.82 for adulthood). Individuals with persistent exposure to passive smoking between childhood and adulthood had the highest risk (relative risk = 1.99, 95% confidence interval: 1.14-3.45) compared with those without passive smoking in either childhood or adulthood.

DISCUSSION

Passive smoking in both child and adult lives are associated with increased risk of adult fatty liver, suggesting that the prevention of passive smoking should start as early as possible and maintain throughout lifetime.

Hepatic and renal damage by alcohol and cigarette smoking in rats

Chronic use of alcohol and tobacco cigarettes is associated to millions of deaths per year, either by direct or indirect causes. However, few studies have explored the additional risks of the combined use of these drugs. Here we assessed the effect of the combined use of alcohol and cigarette smoke on liver or kidney morphology, and on biochemical parameters in chronically treated rats. Male Wistar rats were allocated to receive 2 g/kg alcohol orally, which was followed by the inhalation of smoke from six cigarettes during 2 h (ALTB group) for 28 days. Other groups received alcohol alone (AL) or were exposed to cigarette smoke (TB) alone and were compared to control (CT) rats, which received water followed by ambient air. On day 29, rats were euthanized and blood samples were collected for aminotransferase enzymes (AST and ALT), creatinine, and urea analysis. Liver and kidney were weighted, dissected, fixed, and stained with hematoxylin and eosin for morphological analysis. Our results showed that necrosis was elevated in the AL, TB, and mainly the ALTB group in both liver and kidney of rats. Serum levels of AST and ALT were reduced by cigarette smoke exposure, independently of alcohol use. Serum creatinine levels increased after tobacco smoke exposure. On the other hand, TB and AL groups decreased serum urea levels, and their association restored that decrease. Absolute liver and kidney weights were lower in the cigarette smoke exposure rats. Lastly, body weight gain was lower in TB group and combined use restored it. Thus, we may infer that the use of alcohol, exposure to tobacco cigarette smoke or, mainly, their association promotes liver and kidney injuries, and this damage is related with biochemical changes in rats.

Cigarette smoking exposure breaks the homeostasis of cholesterol and bile acid metabolism and induces gut microbiota dysbiosis in mice with different diets

Exposure of humans to second-hand smoking (SHS) increases glucose and lipid metabolic disorders. The link of hepatic metabolic dysfunction to environmental cigarette smoking has been noticed, but the related mechanism is still unclear. C57BL/6 mice with normal food diet (NFD) or high fat diet (HFD) were exposed to 15 min cigarette smoking twice a day in a 0.038 m³ box for 4 weeks, and the concentration of nicotine in the air of the box was 21.05 mg/m³ during the smoke exposure. Liver tissues and serum were collected for gene expression and biochemistry test. The fecal microbiota was also checked through 16S rDNA sequences. Cigarette smoking exposure increased the accumulation of total cholesterol (TC) in liver, and the expression of cholesterol synthesis-related genes was upregulated. The expression of CYP8B1 protein was significantly down-regulated, and the ratio of cholic acid (CA) to chenodeoxycholic acid (CDCA) was significantly reduced in the liver of mice exposed to cigarette smoking especially for HFD group. Cigarette smoking exposure caused insulin resistance in the liver of mice with HFD. The composition of the gut microbiota was altered with the exposure of cigarette smoking, and the change of the distribution of primary bile acids might be one of the reasons. It was concluded that cigarette smoking would break the homeostasis of cholesterol and bile acids metabolism and changed the composition of gut microbiota. Our discoveries confirmed that smoking bans are important for the public health.

Unravelling the metabolic alterations of liver damage induced by thirdhand smoke

BACKGROUND

Thirdhand smoke (THS) is the accumulation of tobacco smoke gases and particles that become embedded in materials. Previous studies concluded that THS exposure induces oxidative stress and hepatic steatosis in liver. Despite the knowledge of the increasing danger of THS exposure, the metabolic disorders caused in liver are still not well defined.

OBJECTIVES

The aim of this study is to investigate the metabolic disorders caused by THS exposure in liver of male mice and to evaluate the effects of an antioxidant treatment in the exposed mice.

METHODS

We investigated liver from three mice groups: non-exposed mice, exposed to THS in conditions that mimic human exposure and THS-exposed treated with antioxidants. Liver samples were analyzed using a multiplatform untargeted metabolomics approach including nuclear magnetic resonance (1H NMR), liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS) and laser desorption/ionization mass spectrometry imaging (MSI), able to map lipids in liver tissues.

RESULTS

Our multiplatform approach allowed the annotation of eighty-eight metabolites altered by THS exposure, including amino acids, nucleotides and several types of lipids. The main dysregulated pathways by THS exposure were D-glutamine and D-glutamate metabolism, glycerophospholipid metabolism and oxidative phosphorylation and glutathione metabolism, being the last two related to oxidative stress. THS-exposed mice also presented higher lipid accumulation and decrease of metabolites involved in the phosphocholine synthesis, as well as choline deficiency, which is related to Non-Alcoholic Fatty Liver Disease and steatohepatitis. Interestingly, the antioxidant treatment of THS-exposed mice reduced the accumulation of some lipids, but could not revert all the metabolic alterations, including some related to the impairment of the mitochondrial function.

CONCLUSIONS

THS alters liver function at a molecular level, dysregulating many metabolic pathways. The molecular evidences provided here confirm that THS is a new factor for liver steatosis and provide the basis for future research in this respect.

Autonomic Imbalance Increases the Risk for Non-alcoholic Fatty Liver Disease

BACKGROUND

Although autonomic imbalance is associated with an increased risk for metabolic disease, its effects on nonalcoholic fatty liver disease (NAFLD) remains unclear. We aimed to evaluate whether autonomic dysfunction predicts the risk for nonalcoholic fatty liver disease (NAFLD).

METHODS

A total of 33,899 participants without NAFLD who underwent health screening programs between 2011 and 2018 were enrolled. NAFLD was identified by ultrasonography. Autonomic activity was estimated using heart rate variability (HRV). Time domain [standard deviation of the normal-to-normal interval (SDNN) and root mean square difference (RMSSD)]; frequency domain [total power (TP), low frequency (LF), and high frequency (HF), and LF/HF ratio were analyzed.

FINDINGS

A total 6,466 participants developed NAFLD within a median of 5.7 years. Subjects with incident NAFLD showed decreased overall autonomic modulation and vagal activity with lowered SDNN, RMSSD, HF, normalized HF, compared to those without NAFLD. As the SDNN, RMSSD, TP, LF, and HF tertiles increased, the risk of NAFLD decreased with tertile 1 being the reference group [the hazard ratios (95% confidence intervals) of tertile 3 were 0.90 (0.85-0.96), 0.83 (0.78-0.88), 0.91 (0.86-0.97), 0.93 (0.87-0.99) and 0.89 (0.83-0.94), respectively] after adjusting for potential confounders. The risk for NAFLD was significantly higher in subjects in whom sustained elevated heart rate, normalized LF, and LF/HF ratio values than in those with sustained decrease in these parameters during follow-up.

CONCLUSIONS

Overall autonomic imbalance, decreased parasympathetic activity, and recently increased sympathetic activity might increase the risk of NAFLD.

Association Between the Triglyceride-Glucose Index and Outcomes of Nonalcoholic Fatty Liver Disease: A Large-Scale Health Management Cohort Study

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is increasingly becoming a major health burden. Due to the difficulty of liver biopsy, there is no reliable indicator to evaluate the outcomes of NAFLD. The triglyceride-glucose (TyG) index is a simple and convenient marker of insulin resistance for use in medical practice. Whether the TyG index is predictive of later risk of NAFLD remains unknown.

OBJECTIVE

To evaluate the relationship between TyG index with NAFLD progression and improvement during a median follow-up period of 21 months.

MATERIAL AND METHODS

A total of 11,424 subjects (9327 men) diagnosed with NAFLD were included. The TyG index was calculated as follows: ln [fasting triglycerides (mg/dL) * fasting glucose (mg/dL)/2]. Multivariable Cox regression analysis was applied to analyze the data.

RESULTS

In this study, the severity of NAFLD remained the same in 38.8% of subjects, worsened in 17.4% of subjects, and improved in 43.8% of subjects. Compared with the lowest quartile of the TyG index, the adjusted HR of NAFLD progression in the highest quartile (TyG≥9.34) was 1.448 (1.229 to 1.706), and the adjusted HR of NAFLD improvement was 0.817 (0.723 to 0.923). Subgroup analysis found that smoking increased the correlation between the TyG index and the risk of NAFLD progression, while female, vegan diet, and weight control enhanced the correlation between the TyG index and the risk of NAFLD improvement.

CONCLUSION

The TyG index may be a simple and helpful indicator for further risk appraisal of NAFLD in daily clinical practice.

Non-Alcoholic Fatty Liver Disease Is Strongly Associated with Smoking Status and Is Improved by Smoking Cessation in Japanese Males: A Retrospective Study

BACKGROUND

Cigarette smoking is known to be a significant risk factor associated with non-alcoholic fatty liver disease (NAFLD). We aimed to examine the association between smoking status and the severity of fatty liver with regard to sex and smoking cessation.

METHODS

In total, 13,466 subjects (6,642 males and 6,824 females) who had undergone abdominal ultrasonography for health check-up, multivariable logistic regression analysis was retrospectively conducted to assess the association between smoking status and the prevalence of NAFLD stratified by sex after adjusting for other potential confounders.

RESULTS

Male sex (odds ratio [OR] 3.27, 95% confidence interval [CI] 3.00-3.57) and smoking history (former smoker: OR 1.23, 95% CI 1.10-1.38, current smoker: OR 1.31, 95% CI 1.17-1.47) were significantly associated with NAFLD. In males with a smoking history, an increased pack-year was strongly associated with the prevalence and severity of NAFLD (prevalence of moderate to severe fatty liver: Pack-year from 0.01 to 9.99, 21.3%; Pack-year from 10.00 to 19.99, 27.2%; Pack-year ≥20.00, 33.7%; P<0.0001), although the prevalence of moderate to severe fatty liver was inversely associated with the duration of smoking cessation (more than 10 years vs. within 5 years, OR 0.71, 95% CI 0.53-0.96). In female subjects, light current smoking was negatively associated with NAFLD (current smoker with a pack-year from 0.01 to 9.99 vs. never smoker, OR 0.41, 95% CI 0.19-0.76).

CONCLUSIONS

Smoking status and pack-year were strongly associated with the prevalence and severity of NAFLD, especially in Japanese males. However, smoking cessation improved NAFLD in this population.

Prenatal Exposure to Gutkha, a Globally Relevant Smokeless Tobacco Product, Induces Hepatic Changes in Adult Mice

Maternal exposures during pregnancy affect the onset and progression of adult diseases in the offspring. A prior mouse study indicated that maternal tobacco smoke exposure affects hepatic fibrosis in adult offspring. Gutkha, a broadly used smokeless tobacco (ST) product, is widely used by pregnant woman in many countries. The objective of this murine study was to evaluate whether oral maternal exposure to gutkha during pregnancy alters non-alcoholic fatty liver disease (NAFLD) in adult offspring: risk factors for the progression of NAFLD to cirrhosis in adults remain elusive. Buccal cavity 'painting' of pregnant mice with gutkha began on gestational days (GD) 2-4 and continued until parturition. Beginning at 12 weeks of age, a subset of offspring were transitioned to a high-fat diet (HFD). Results demonstrated that prenatal exposure to gutkha followed by an HFD in adulthood significantly increased the histologic evidence of fatty liver disease only in adult male offspring. Changes in hepatic fibrosis-related cytokines (interleukin (IL)-1b and IL-6) and in hepatic collagen mRNA expression were observed when comparing adult male offspring exposed to gutkha in utero to those not exposed. These findings indicate that maternal use of gutkha during pregnancy affects NAFLD in adult offspring in a sex-dependent manner.

Farnesoid X receptor mediates hepatic steatosis induced by PM2.5

Ambient particulate matter (PM) newly has been regarded as a conceivable hazard for public health. A large number of studies have described that PM, exceptionally PM2.5, is correlated with respiratory, cardiovascular, and metabolic diseases, etc. PM2.5-induced hepatocyte steatosis previously has been uncovered both in cellular and murine models. Nevertheless, less is known about the underlying mechanism. Here, we found that PM2.5 could cause the downregulation of farnesoid X receptor (FXR), a key transcription factor for lipid metabolism. FXR could regulate the accumulation of lipid droplets induced by PM2.5 in vitro. Moreover, FXR-/- mice were exposed to PM2.5 for 2 months to investigate the role of FXR in pathogenesis of PM2.5-induced hepatic steatosis in vivo. The results showed that exposure of wild-type (WT) mice to PM2.5 caused mild liver steatosis compared with the mice exposure to filtered air (FA). Furthermore, the content of triglyceride (TG) and total cholesterol (TC) was elevated in WT mice liver triggered by the inhalation of PM2.5. However, there was no statistical difference in TG and TC content between FXR-/- mice with and without PM2.5 exposure. Overall, our finding suggested FXR mediated PM2.5-induced hepatic steatosis.

Serum Soluble Receptor for AGE (sRAGE) Levels Are Associated With Unhealthy Lifestyle and Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) has been demonstrated to be positively associated with serum advanced glycation end products (AGEs) and negatively with soluble receptor for AGE (sRAGE) in a few small studies. We aimed to test the association between lifestyle and sRAGE levels and the association between sRAGE levels or AGEs intake and NAFLD, insulin resistance (IR), and elevated alanine aminotransferase (ALT).

Non-Alcoholic Fatty Liver Disease Modifies Serum Gamma-Glutamyl Transferase in Cigarette Smokers

Background

Serum gamma-glutamyl transferase (GGT) is a marker of oxidative stress, associated with increased cardiovascular (CV) risk. The impact of smoking on oxidative stress may be aggravated in individuals with non-alcoholic fatty liver disease (NAFLD). We aimed to ascertain the association of smoking on GGT levels in the presence or absence of NAFLD.

Methods

We evaluated 6,354 healthy subjects (43 ± 10 years, 79% males) without clinical cardiovascular disease (CVD) undergoing an employer-sponsored physical between December 2008 and December 2010. NAFLD was diagnosed by ultrasound and participants were categorized as current or non-smokers by self report. A multivariate linear regression of the cross-sectional association between smoking and GGT was conducted based on NAFLD status.

Results

The prevalence of NAFLD was 36% (n = 2,299) and 564 (9%) were current smokers. Smokers had significantly higher GGT levels in the presence of NAFLD (P < 0.001). After multivariable adjustment, current smoking was associated with 4.65 IU/L higher GGT level, P < 0.001, compared to non-smokers. When stratified by NAFLD, the magnitude of this association was higher in subjects with NAFLD (β-coefficient: 11.12; 95% confidence interval (CI): 5.76 - 16.48; P < 0.001); however, no such relationship was observed in those without NAFLD (β: -0.02; 95% CI: -3.59, 3.56; P = 0.992). Overall the interaction of NAFLD and smoking with GGT levels as markers of oxidative stress was statistically significant.

Conclusions

Smoking is independently associated with significantly increased oxidative stress as measured by GGT level. This association demonstrates effect modification by NAFLD status, suggesting that smoking may intensify CV risk in individuals with NAFLD.

Obesity and metabolic outcomes in a safety-net health system

In the United States, obesity has increased in prevalence over time and is strongly associated with subsequent outcomes such as diabetes mellitus (DM) and nonalcoholic fatty liver disease (NAFLD). It is unclear, however, as to how the magnitude of NAFLD risk from obesity and DM is increased in safety-net health system settings. Among the San Francisco Health Network (SFHN) patients (N = 47,211), we examined the association between Body Mass Index (BMI) and elevated liver enzyme levels, including interaction by DM status. Our findings revealed that 32.2 percent of SFHN patients were obese, and Pacific Islanders in the safety-net had the highest rates of obesity compared to other racial groups, even after using higher race-specific BMI cutoffs. In SFHN, obesity was associated with elevated liver enzymes, with the relationship stronger among those without DM. Our findings highlight how obesity is a stronger factor of NAFLD in the absence of DM, suggesting that practitioners consider screening for NAFLD among safety-net patients with obesity even if DM has not developed. These results highlight the importance of directing efforts to reduce obesity in safety-net health systems and encourage researchers to further examine effect modification between health outcomes in such populations.

Validation of a Non-Laboratory Based Screening Tool for Predicting Non-Alcoholic Fatty Liver Disease in an Egyptian Setting

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disorder in more than 20% of the general population worldwide.  Several combinations of non-invasive factors and scoring models were investigated as indicators of NAFLD. This study aimed to validate and adapt an established fatty liver score, which allows the identification of NAFLD based on routinely available clinical and laboratory data.

MATERIALS AND METHODS

The study cohort comprised 190 adults seeking health check-up at the out-patient clinic of a tertiary care hospital in Alexandria, Egypt. Anthropometric, clinical, and laboratory data were recorded and the status of fatty liver was diagnosed by abdominal ultrasound. A logistic regression model was built to determine the predictors of NAFLD. The performance of the derived risk scores was compared to other existing models.

RESULTS

Obesity (60.0%), metabolic syndrome (42.6%), and NAFLD (56.8%) were predominant features among the study population. Smoking [OR (95% CI) = 4.4 (0.9-21.4)], obesity [OR (95% CI) = 4.0 (1.7-9.7)], hypertension [OR (95% CI) = 2.4 (1.03-5.5)], elevated serum total cholesterol [OR (95% CI) = 4.8 (1.8-13.1)], triglycerides [OR (95% CI) = 11.8 (2.3-661.02)], and ALT [OR (95% CI) = 4.8 (1.8-13.1)] were multivariate predictors of NAFLD. A NAFLD screening questionnaire with values applicable for Egyptians was adapted from an existing model after validation. A total score ≥7 was suggestive of NAFLD [AUC = 0.810 (0.749-0.871); sensitivity = 87.0%; specificity = 62.2%; PPV = 75.2%; NPV = 78.5%].

CONCLUSIONS

NAFLD can be sufficiently predicted among apparently healthy Egyptians by a tempted simple and non-invasive scoring index although external validation is warranted.

Decreased Vagal Activity and Deviation in Sympathetic Activity Precedes Development of Diabetes

OBJECTIVE

The objective of this study was to examine whether altered heart rate variability (HRV) could predict the risk of diabetes in Asians.

RESEARCH DESIGN AND METHODS

A cohort study was conducted in 54,075 adults without diabetes who underwent 3-min HRV measurement during health checkups between 2011 and 2014 at Kangbuk Samsung Hospital. We analyzed the time domain (SD of the normal-to-normal interval [SDNN] and root mean square differences of successive normal-to-normal intervals [RMSSD]) and the frequency domain (total power, normalized low-frequency power [LF], and normalized high-frequency power [HF] and LF/HF ratio). We compared the risk of diabetes until 2017 according to tertiles of heart rate and HRV variables, with tertile 1 serving as the reference group.

RESULTS

During 243,758.2 person-years, 1,369 subjects were diagnosed with diabetes. Both time and frequency domain variables were lower in the group with diabetes, with the exception of those with normalized LF and LF/HF ratio. In Cox analysis, as SDNN, RMSSD, and normalized HF tertiles increased, the risk of diabetes decreased (hazard ratios [95% CIs] of tertile 3: 0.81 [0.70-0.95], 0.76 [0.65-0.90], and 0.78 [0.67-0.91], respectively), whereas the risk of diabetes increased in the case of heart rate, normalized LF, and LF/HF ratio (hazard ratios [95% CIs] of tertile 3: 1.41 [1.21-1.65], 1.32 [1.13-1.53], and 1.31 [1.13-1.53), respectively) after adjusting for age, sex, BMI, smoking, drinking, systolic blood pressure, lipid level, CRP, and HOMA of insulin resistance.

CONCLUSIONS

Abnormal HRV, especially decreased vagal activity and deviation in sympathovagal imbalance to sympathetic activity, might precede incident diabetes.

AGA Clinical Practice Update on Screening and Surveillance for Hepatocellular Carcinoma in Patients With Nonalcoholic Fatty Liver Disease: Expert Review

Nonalcoholic fatty liver disease (NAFLD) is a leading etiology for chronic liver disease with an immense public health impact and affects >25% of the US and global population. Up to 1 in 4 NAFLD patients may have nonalcoholic steatohepatitis (NASH). NASH is associated with significant morbidity and mortality due to complications of liver cirrhosis, hepatic decompensation, and hepatocellular carcinoma (HCC). Recent data confirm that HCC represents the fifth most common cancer and is the second leading cause of cancer-related death worldwide, and NAFLD has been identified as a rapidly emerging risk factor for this malignancy. NAFLD-associated liver complications are projected to become the leading indication for liver transplantation in the next decade. Despite evidence that NAFLD-associated HCC may arise in the absence of cirrhosis, is often diagnosed at advanced stages, and is associated with lower receipt of curative therapy and with poorer survival, current society guidelines provide limited guidance/recommendations addressing HCC surveillance in patients with NAFLD outside the context of established cirrhosis. Limited data are presently available to guide clinicians with respect to which patients with NAFLD should undergo HCC surveillance, optimal screening tools, frequency of monitoring, and the influence of coexisting host- and disease-related risk factors. Herein we present an evidence-based review addressing HCC risk in patients with NAFLD and provide Best Practice Advice statements to address key issues in clinical management.

Secondhand Smoke Induces Liver Steatosis through Deregulation of Genes Involved in Hepatic Lipid Metabolism

We investigated the role of secondhand smoke (SHS) exposure, independently of diet, in the development of chronic liver disease. Standard diet-fed mice were exposed to SHS (5 h/day, 5 days/week for 4 months). Genome-wide gene expression analysis, together with molecular pathways and gene network analyses, and histological examination for lipid accumulation, inflammation, fibrosis, and glycogen deposition were performed on the liver of SHS-exposed mice and controls, upon termination of exposure and after one-month recovery in clean air. Aberrantly expressed transcripts were found in the liver of SHS-exposed mice both pre- and post-recovery in clean air (n = 473 vs. 222). The persistent deregulated transcripts (n = 210) predominantly affected genes and functional networks involved in lipid metabolism as well as in the regulation of the endoplasmic reticulum where manufacturing of lipids occurs. Significant hepatic fat accumulation (steatosis) was observed in the SHS-exposed mice, which progressively increased as the animals underwent recovery in clean air. Moderate increases in lobular inflammation infiltrates and collagen deposition as well as loss of glycogen were also detectable in the liver of SHS-exposed mice. A more pronounced phenotype, manifested as a disrupted cord-like architecture with foci of necrosis, apoptosis, inflammation, and macrovesicular steatosis, was observed in the liver of SHS-exposed mice post-recovery. The progressive accumulation of hepatic fat and other adverse histological changes in the SHS-exposed mice are highly consistent with the perturbation of key lipid genes and associated pathways in the corresponding animals. Our data support a role for SHS in the genesis and progression of metabolic liver disease through deregulation of genes and molecular pathways and functional networks involved in lipid homeostasis.

Solid fuels for cooking and tobacco use and risk of major chronic liver disease mortality: a prospective cohort study of 0.5 million Chinese adults

BACKGROUND

Harmful substances in solid fuel and tobacco smoke are believed to enter the bloodstream via inhalation and to be metabolized in the liver, leading to chronic liver damage. However, little is known about the independent and joint effects of solid fuel use and smoking on risks of chronic liver disease (CLD) mortality.

METHODS

During 2004-08, ∼0.5 million adults aged 30-79 years were recruited from 10 areas across China. During a 10-year median follow-up, 2461 CLD deaths were recorded. Multivariable Cox regression yielded adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for the individual associations of self-reported long-term cooking fuel and tobacco use with major CLD death.

RESULTS

Overall, 49% reported solid fuel use and 26% smoked regularly. Long-term solid fuel use for cooking and current smoking were associated with higher risks of CLD deaths, with adjusted HRs of 1.26 (95% CI, 1.02-1.56) and 1.28 (1.13-1.44), respectively. Compared with never-smoking clean fuel users, the HRs were 1.41 (1.10-1.82) in never-smoking solid fuel users, 1.55 (1.17-2.06) in regular-smoking clean fuel users and 1.71 (1.32-2.20) in regular-smoking solid fuels users. Individuals who had switched from solid to clean fuels (1.07, 0.90-1.29; for median 14 years) and ex-regular smokers who stopped for non-medical reasons (1.16, 0.95-1.43; for median 10 years) had no evidence of excess risk of CLD deaths compared with clean fuel users and never-regular smokers, respectively.

CONCLUSIONS

Among Chinese adults, long-term solid fuel use for cooking and smoking were each independently associated with higher risks of CLD deaths. Individuals who had stopped using solid fuels or smoking had lower risks.

Risk Factors For Hyperuricemia In Chinese Centenarians And Near-Centenarians

Purpose

Hyperuricemia is an important potential pathogenic factor for hypertension, cardiovascular disease and stroke. The current study aimed to investigate the prevalence of hyperuricemia and its relationship to lifestyle characteristics and dietary habits in centenarians and near-centenarians.

Patients and methods

In total, 966 centenarians and 788 near-centenarians were included. Community-based surveys were conducted to collect information about lifestyle. Blood examinations were performed using enzymatic assays. T-tests and χ2 tests were used to investigate significant indicators of hyperuricemia, and multivariate logistic regression was used to analyze the related risk factors. A comprehensive analysis of nineteen modifiable factors, including lifestyle characteristics, dietary habits, general characteristics and blood test indexes, was conducted.

Results

The prevalence of hyperuricemia was 29.02%. The percentage of men, waist circumference (WC), waist-hip ratio, estimated glomerular filtration rate (eGFR), levels of total protein (TP), alanine aminotransferase, aspartate aminotransferase, triglycerides, high-density lipoprotein cholesterol, serum homocysteine, serum uric acid, serum urea and serum creatinine, passive smoking, alcohol consumption, snoring, preference for fried flavors, and meat, seafood and vegetable consumption were significantly different between the hyperuricemia group and the normouricemia group (p<0.05). Multivariate logistic regression analysis showed that WC (OR=1.020), eGFR (OR=0.960), TP level (OR=1.038), serum urea level (OR=1.154), passive smoking (OR=2.589), snoring (OR=2.003), meat consumption (OR=2.506), seafood consumption (OR=1.422) and vegetable consumption (OR=0.521) were significantly associated with the risk of hyperuricemia (p<0.05).

Conclusion

Low eGFR and vegetable consumption, high WC, TP, and serum urea levels, passive smoking, snoring, and high meat and seafood consumption were independent risk factors for hyperuricemia. It is recommended that people at high risk for hyperuricemia should actively limit their intake of fried food, alcohol and purine-rich food, increase their intake of fresh vegetables, actively treat sleep apnea syndrome, avoid passive smoking, maintain a healthy WC and seek to improve their kidney and liver function.

Elevated prevalence of moderate-to-severe hepatic steatosis in World Trade Center General Responder Cohort in a program of CT lung screening

BACKGROUND AND AIMS

To determine the prevalence of moderate-to-severe hepatic steatosis (HS) and associated risk factors in members of the World Trade Center (WTC) General Responder Cohort (GRC) who qualify for low-dose non-contrast computed tomography for lung cancer screening and compare them to non-WTC participants in the same screening program.

METHODS

All participants gave written informed consent before participating in this IRB-approved study. Clinical variables and laboratory values were recorded. Hepatic attenuation measurement (Hounsfield unit; HU) was measured on low-dose computed tomography (LDCT) and a threshold attenuation value <40HU indicated moderate-to-severe HS. Bivariate and multivariable linear and logistic regression analyses were performed. Propensity scores (PS) were calculated and inverse probability weighting (IPW) was used to adjust for potential confounders when comparing the WTC with non-WTC participants.

RESULTS

The prevalence of moderate-to-severe HS was 16.2% among 154 WTC participants compared to 5.3% among 170 non-WTC participants. In WTC members, moderate-to-severe HS was associated with higher BMI, higher laboratory liver function tests, and former smoking status. Using PS analysis and IPW to account for potential confounders, the odds ratio for moderate-to-severe HS was 3.4-fold higher (95% confidence interval: 1.7-6.7) in the WTC participants compared with non-WTC participants. Moderate-to-severe HS was also associated with higher BMI and former smoker status.

CONCLUSION

Prevalence of moderate-to-severe HS was >3-fold higher in the WTC-GRC group than in other participants.

Cigarette smoking differentially regulates inflammatory responses in a mouse model of nonalcoholic steatohepatitis depending on exposure time point

Cigarette smoke (CS) is a risk factor for the development of nonalcoholic fatty liver disease. However, the role of mainstream CS (MSCS) in the pathogenesis of nonalcoholic steatohepatitis (NASH) remains unclear. During the first (early exposure) or last (late exposure) three weeks of methionine-choline deficient with high fat diet feeding (6 weeks), each diet group was exposed to MSCS (300 or 600 μg/L). Hepatic or serum biochemical analysis showed that MSCS differentially modulated hepatic injury in NASH milieu, depending on exposure time points. Consistently, NASH-related hepatocellular apoptosis and fibrosis were increased in the early exposure group, but decreased in the late exposure group, except for steatosis. Ex vivo experiments showed that CS extract differentially regulated inflammatory responses in co-cultured hepatocytes and macrophages isolated from steatohepatitic livers after 10 days or 3 weeks of diet feeding. Furthermore, CS differentially up- and down-regulated the expression levels of M1/M2 polarization markers and peroxisome proliferator-activated receptor-gamma (PPARγ) in livers (29% and 38%, respectively) or co-cultured macrophages (2 and 2.5 fold, respectively). Collectively, our findings indicate that opposite effects of MSCS on NASH progression are mediated by differential modulation of PPARγ and its-associated M1/M2 polarization in hepatic macrophages, depending on exposure time points.