Low- and high-density lipoprotein subclasses in subjects with nonalcoholic fatty liver disease

Elevated small dense low-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio is associated with an increased risk of metabolic dysfunction associated fatty liver disease in Chinese patients with type 2 diabetes mellitus

INTRODUCTION

It is demonstrated that elevated small dense low-density lipoprotein cholesterol (sdLDL-C), and reduced high-density lipoprotein cholesterol (HDL-C) is associated with Metabolic dysfunction-associated fatty liver disease (MAFLD). This study aims to explore the relationship between sdLDL-C to HDL-C ratio (SHR) and MAFLD in Chinese patients with type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

A cross-sectional study was performed among 1904 patients with T2DM. Weighted multivariable logistic regression analysis was conducted to explore the relationship between the SHR and the risk of MAFLD. In addition, this study used a two-part linear regression model to identify threshold effects. Subgroup analysis, interaction tests and receiver operating characteristic (ROC) curve analysis were also carried out.

RESULTS

The overall MAFLD prevalence reached 48.1%. Multiple logistic regression analysis showed that SHR was positively correlated with the risk of MAFLD (OR = 2.37, 95% CI = 1.80-3.12). Subgroup analysis stratified by age, gender, hypertension and BMI showed that there was a consistent positive correlation. A non-linear relationship and saturation effect between SHR and MAFLD risk were identified, with an inverted L shaped curve and an inflection point at 1.02. The area under the curve (AUC) for SHR in the ROC analysis was significantly greater than sdLDL-C and HDL-C, with a sensitivity of 71.2% and a specificity of 62.1%.

CONCLUSIONS

Elevated levels of SHR is independently associated with an increased risk of MAFLD in patients with T2DM. SHR may be taken as practical indicators to assess the risk of MAFLD in T2DM patients.

Estimated small dense low-density lipoprotein cholesterol and nonalcoholic fatty liver disease in nonobese populations

AIMS/INTRODUCTION

To explore the association between estimated small dense low-density lipoprotein cholesterol (sdLDL-C) and the risk of incident nonalcoholic fatty liver disease (NAFLD) in nonobese populations.

MATERIALS AND METHODS

This study included participants who underwent health checkups in 2014 and were followed up until 2019. We carried out Cox proportional hazards regression analyses to evaluate the association of estimated sdLDL-C with NAFLD. Discordance analyses were carried out to estimate the relative NAFLD risk in estimated sdLDL-C versus low-density lipoprotein cholesterol (LDL-C) discordant/concordant groups. Estimated sdLDL-C was calculated by equations based on LDL-C and triglycerides. The diagnosis of NAFLD was based on the presence of abdominal ultrasonography after excluding other causes of chronic liver disease.

RESULTS

Over a mean follow-up period of 26,694 person-years, 844 incident NAFLD cases were recorded. Compared with the first quartile of estimated sdLDL-C, the fourth quartile was associated with a 2.933-fold increased risk of NAFLD (95% confidence interval 2.095-4.107). With the increase in estimated sdLDL-C, the risk of NAFLD gradually increased both in participants within the normal range of LDL-C (hazard ratio 2.854, 95% confidence interval 1.650-5.617) and beyond the normal range of LDL-C (hazard ratio 2.636, 95% confidence interval 1.263-5.502). In addition, the inconsistent high estimated sdLDL-C/low LDL-C group was associated with an increased risk of NAFLD, but not the low estimated sdLDL-C/high LDL-C group.

CONCLUSIONS

Estimated sdLDL-C was positively associated with the risk of incident NAFLD in a nonobese population, independent of LDL-C.

Specific Increase in Small Dense Low-Density Lipoprotein-Cholesterol Levels beyond Triglycerides in Patients with Diabetes: Implications for Cardiovascular Risk of MAFLD

AIMS

Small dense (sd) low-density lipoprotein (LDL)-cholesterol (C) is the most powerful predictor of cardiovascular (CV) disease among lipid biomarkers and is generated by hypertriglyceridemia and insulin resistance. Metabolic dysfunction-associated fatty liver disease (MAFLD) is a newly proposed liver disease with a high CV risk. We investigated the specific association of sdLDL-C with MAFLD beyond triglycerides (TG) and obesityMethods: Participants were 839 non-alcoholic drinkers with type 2 diabetes enrolled in a regional diabetes cohort. Fatty liver (FL) and visceral fat area (VFA) was detected by computed tomography scan. sdLDL-C and LDL-TG were measured by our established homogeneous assay. TG rich lipoprotein (TRL) was calculated by subtracting LDL-C plus HDL-C from total-C. Grade of sdLDL-C (≤ 24, 25-34, 35-44, and ≥ 45 mg/dL) was classified according to the Hisayama study.

RESULTS

Compared to non-FL counterparts, FL subjects were younger, predominantly male and smokers; and had higher body mass index (BMI), VFA, hemoglobin A1c, C-peptide, TG, and sdLDL-C, while had similar levels of LDL-C, LDL-TG, and TRL-C. Multivariate logistic analysis revealed that sdLDL-C was the most powerful lipid parameter for identifying FL, independent of TG, HDL-C, BMI, and VFA. The independent association between TG and FL was lost when sdLDL-C was added to the analysis. These results remained the same when lipid-lowering drug users were excluded. After adjustment for confounders, the odds ratio for FL was 2.4-2.7 at sdLDL ≥ 35 mg/dL based on sdLDL ≤ 24 mg/dL.

CONCLUSIONS

sdLDL-C levels are specifically elevated in patients with diabetes and MAFLD, independent of TG and VFA, suggesting liver-centered metabolic abnormalities.

The roles of nuclear receptors in cholesterol metabolism and reverse cholesterol transport in nonalcoholic fatty liver disease

As the most prevalent chronic liver disease globally, NAFLD encompasses a pathological process that ranges from simple steatosis to NASH, fibrosis, cirrhosis, and HCC, closely associated with numerous extrahepatic diseases. While the initial etiology was believed to be hepatocyte injury caused by lipid toxicity from accumulated triglycerides, recent studies suggest that an imbalance of cholesterol homeostasis is of greater significance. The role of nuclear receptors in regulating liver cholesterol homeostasis has been demonstrated to be crucial. This review summarizes the roles and regulatory mechanisms of nuclear receptors in the 3 main aspects of cholesterol production, excretion, and storage in the liver, as well as their cross talk in reverse cholesterol transport. It is hoped that this review will offer new insights and theoretical foundations for the study of the pathogenesis and progression of NAFLD and provide new research directions for extrahepatic diseases associated with NAFLD.

The role of atherogenic lipoproteins in diabetes: Molecular aspects and clinical significance

Dyslipidaemia plays a prominent role in the genesis of atherosclerotic plaque and the increased cardiovascular risk in diabetes. Macrophages readily take up atherogenic lipoproteins, transforming into foam cells and amplifying vascular damage in the presence of endothelial dysfunction. We discuss the importance of distinct lipoprotein subclasses in atherogenic diabetic dyslipidaemia as well as the effects of novel anti-diabetic agents on lipoprotein fractions and ultimately on cardiovascular risk prevention. In patients with diabetes, lipid abnormalities should be aggressively identified and treated in conjunction with therapeutical agents used to prevent cardiovascular disease. The use of drugs that improve diabetic dyslipidaemia plays a prominent role in conferring cardiovascular benefit in individuals with diabetes.

Immune and metabolic cross-links in the pathogenesis of comorbid non-alcoholic fatty liver disease

In recent years, there has been a steady growth of interest in non-alcoholic fatty liver disease (NAFLD), which is associated with negative epidemiological data on the prevalence of the disease and its clinical significance. NAFLD is closely related to the metabolic syndrome and these relationships are the subject of active research. A growing body of evidence shows cross-linkages between metabolic abnormalities and the innate immune system in the development and progression of NAFLD. These links are bidirectional and largely still unclear, but a better understanding of them will improve the quality of diagnosis and management of patients. In addition, lipid metabolic disorders and the innate immune system link NAFLD with other diseases, such as atherosclerosis, which is of great clinical importance.

Differences in HDL-Bound Apolipoproteins in Patients With Advanced Liver Fibrosis Due to Nonalcoholic Fatty Liver Disease

CONTEXT

The mechanisms leading to increased cardiovascular disease in patients with nonalcoholic fatty liver disease (NAFLD) and advanced liver fibrosis remain incompletely understood.

OBJECTIVE

This study assessed HDL-bound proteins in patients with NAFLD with or without advanced fibrosis.

METHODS

This cross-sectional study at a university hospital included 185 patients with or without type 2 diabetes (T2D). Patients underwent liver proton magnetic resonance spectroscopy to measure intrahepatic triglyceride accumulation and those with NAFLD underwent a percutaneous liver biopsy. Advanced lipid testing with lipoprotein subfraction measurements and targeted proteomics of HDL-bound proteins was performed.

RESULTS

Patients with and without advanced fibrosis had similar clinical characteristics, except for lower HDL-C (34 ± 8 vs 38 ± 9 mg/dL, P = 0.024) and higher prevalence of T2D in advanced fibrosis. Patients with advanced fibrosis had lower HDL particle number. A panel of 28 HDL-bound proteins were targeted and quantified by multiple reaction monitoring liquid chromatography-tandem mass spectrometry. Five proteins were found to be decreased in patients with advanced fibrosis (ApoC-I [P < 0.001], ApoC-IV [P = 0.012], ApoM [P = 0.008], LCAT [P = 0.014], and SAA4 [P = 0.016]). No differences were observed in these proteins in patients with vs without NAFLD or steatohepatitis. The pCAD index, associated with coronary artery disease and cardiovascular mortality, was significantly higher in patients with advanced fibrosis (97 ± 5 vs 86 ± 25, P = 0.04).

CONCLUSION

Patients with NAFLD with advanced fibrosis showed significant differences in HDL-bound protein levels; this translated into increased cardiovascular risk based on pCAD index. Different lipoprotein composition and function may explain the link between liver disease and increased cardiovascular mortality in these patients.

A cross-sectional study assessing the relationship between non-alcoholic fatty liver disease and periodontal disease

The risk factors for non-alcoholic fatty liver disease (NAFLD) progression are not completely known. Porphyromonas gingivalis infection is a risk factor for systemic diseases. We investigated the association of P. gingivalis infection with the risk of non-alcoholic steatohepatitis progression. Here, hematological tests, periodontal examination, and saliva collection were performed for 164 patients with NAFLD. P. gingivalis was identified in saliva using polymerase chain reaction. Hepatic steatosis and stiffness were evaluated using vibration-controlled transient elastography (VCTE) and magnetic resonance imaging. In patients with NAFLD, P. gingivalis positivity (P. gingivalis ratio ≥ 0.01%) in saliva correlated with liver stiffness determined using magnetic resonance elastography (MRE; p < 0.0001). A P. gingivalis ratio of 0.01% corresponds to 100,000 cells/mL and indicates the proportion of P. gingivalis in the total number of bacteria in the oral cavity. Patients with NAFLD and advanced fibrosis on MRE showed significantly elevated endotoxin activity; those who had > 10 periodontal pockets with depths ≥ 4 mm had significantly increased hepatic stiffness on both VCTE and MRE.

Risk for hepatic and extra-hepatic outcomes in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is defined by presence of steatosis in more than 5% of liver cells. The gold standard for diagnosis is liver biopsy, but this is seldom achieved due to costs and risk for side effects, and that is why the diagnosis is mostly made based on a combination of radiology and exclusion of other liver diseases. Disease severity staging can be noninvasively achieved with radiological exams such as elastography or blood-based markers that usually have lower sensitivity and specificity. NAFLD is today the most common chronic liver disease globally with a prevalence estimated to be 25%. Fortunately, for many persons NAFLD is an incidental finding with a good prognosis. Whilst a major focus has been on liver-related outcomes in NAFLD, there has recently been an increased interest in extrahepatic consequences of NAFLD. The most commonly studied outcomes include cardiovascular disease and cancer. The risk of adverse outcomes generally differs according to the baseline fibrosis stage. There is a five-time higher risk of liver-related events in NAFLD patients with fibrosis stage 3 as compared to those with no or little fibrosis. Meanwhile, the presence of nonalcoholic steatohepatitis (NASH) does not seem to influence prognosis in addition to fibrosis stage. Patients with NAFLD clearly have a higher risk for cardiovascular outcomes compared to the general population, with a recent meta-analysis indicating a 37% increased hazard for cardiovascular events as opposed to individuals without NAFLD. The risk of liver cancer is increased, which is mostly driven by presence of cirrhosis, but the increased risk is present also in patients without cirrhosis, and to a greater extent than for other chronic liver disease. Around one-third of patients with NAFLD and liver cancer do not have cirrhosis. Additionally, the risk of extrahepatic malignancies is thought to be moderately increased, with most evidence for a link between NAFLD and colorectal cancer where the risk is approximately 50% higher compared to patients without NAFLD. A particularly salient point is if NAFLD can be considered an independent risk factor for outcomes. Many studies have not been able to adjust for key confounders, or suffer from different forms of bias. The clinical problem is nevertheless to identify persons with an increased risk for adverse hepatic and extrahepatic outcomes. We here discuss the evidence linking NAFLD to severe hepatic and extrahepatic outcomes.

Ultrasonographic index for the diagnosis of non-alcoholic steatohepatitis in patients with non-alcoholic fatty liver disease

BACKGROUND

Liver biopsy is a gold standard for the diagnosis of non-alcoholic steatohepatitis (NASH), but has several disadvantages including invasiveness, high cost, and sampling error. Ultrasonography (US) is a noninvasive imaging modality widely used in non-alcoholic fatty liver disease (NAFLD) patients. This study aimed: (I) to assess the feasibility of US in the prediction of NASH and (II) to develop various US indices combining US parameters and laboratory data for the detection of NASH in NAFLD patients and to compare the diagnostic performance of them.

METHODS

Sixty patients who underwent liver biopsy, gray-scale US [hepatorenal index (HRI) and shear-wave elastography (SWE)], and Fibroscan [controlled attenuation parameter (CAP) and transient elastography (TE)] for the evaluation of NASH were included. Patients were classified according to the NAFLD Activity Score (NAS) into the NASH (NAS ≥5) and non-NASH (NAS <5) groups. The diagnostic performance of HRI, CAP, SWE, TE, and laboratory data for grading steatosis, lobular inflammation, ballooning degeneration, and fibrosis was evaluated. After the identification of laboratory data that were independently associated with NASH through univariable and multivariable logistic regression analyses, various US indices were developed by combining US parameters with or without these laboratory data. The diagnostic performance of the US indices was assessed with obtaining area under the curve (AUC) and compared using DeLong test.

RESULTS

Twenty-five NASH and 35 non-NASH patients were included. The mean AUCs for grading steatosis were 0.871 using HRI and 0.583 using CAP. The mean AUCs for grading fibrosis and ballooning degeneration were 0.777 and 0.729 using SWE and 0.830 and 0.708 using TE, respectively. Aspartate aminotransferase (AST) was the only significant laboratory data associated with NASH (OR, 1.019; P=0.032). Using AST, the mean AUCs for grading lobular inflammation and ballooning degeneration were 0.712 and 0.775, respectively. Among various US indices, the index consisting of gray-scale US parameters (SWE and HRI) and AST showed the best diagnostic performance for the detection of NASH in NAFLD patients (AUC =0.806).

CONCLUSIONS

The index combining gray-scale US parameters and AST is useful for the detection of NASH and may be used to exclude the need for liver biopsy in NAFLD patients.

A New Look at Novel Cardiovascular Risk Biomarkers: The Role of Atherogenic Lipoproteins and Innovative Antidiabetic Therapies

The presence of residual cardiovascular disease (CVD) risk is a current dilemma in clinical practice; indeed, despite optimal management and treatment, a considerable proportion of patients still undergo major CV events. Novel lipoprotein biomarkers are suggested as possible targets for improving the outcomes of patients at higher risk for CVD, and their impact on major CV events and mortality have previously been investigated. Innovative antidiabetic therapies have recently shown a significant reduction in atherogenic lipoproteins, beyond their effects on glucose parameters; it has also been suggested that such anti-atherogenic effect may represent a valuable mechanistic explanation for the cardiovascular benefit of, at least, some of the novel antidiabetic agents, such as glucagon-like peptide-1 receptor agonists. This emphasizes the need for further research in the field in order to clearly assess the effects of innovative treatments on different novel biomarkers, including atherogenic lipoproteins, such as small dense low-density lipoprotein (LDL), lipoprotein(a) (Lp(a)) and dysfunctional high-density lipoprotein (HDL). The current article discusses the clinical importance of novel lipid biomarkers for better management of patients in order to overcome residual cardiovascular risk.

Associations between the lipid profile and the development of hypertension in young individuals - the preliminary study

INTRODUCTION

Hypertension is the leading direct cause of death in the world and one of the most important risk factors for cardiovascular disease (CVD). Elevated blood pressure (BP) often coexists with lipid disorders and is an additional factor that increases CV risk. Nowadays, we are able to distinguish low density lipoproteins (LDL) and high density lipoproteins (HDL) subfractions. Except LDL also HDL small subfractions can increase the risk of CV events. Therefore, we aimed to investigate the associations between changes of lipoprotein subfractions and the risk of hypertension development.

MATERIAL AND METHODS

In 2-year long study 200 volunteers with normal blood pressure at the age of 19-32 years were included. Each volunteer underwent detailed medical examination, 12-lead electrocardiogram was taken at rest, echocardiogram, lipid subfraction assessment (using Lipoprint^®) and two 24-hour BP measurements.

RESULTS

Mean total cholesterol concentration was 189 mg/dl (4.89 mmol/l), with mean LDL concentration of 107 mg/dl (2.77 mmol/l), HDL of 63 mg/dl (1.63 mmo/l), very low-density lipoprotein (VLDL) of 40 mg/dl (1.04 mmol/l) and triglycerides (TG) of 89 mg/dl (1.00 mmol/l). Subfractions LDL 1-3 were most abundant, LDL 4-5 making up a marginal portion and LDL 6-7 were not observed. Whereas, subfractions HDL 4-6 were most abundant, in lower concentration was present HDL 1-3 and HDL 8-10. We showed that increased systolic blood pressure coreclated significantly with HDL cholesterol concentrations (p = 0.0078), HDL intermediate subgractions (p = 0.0451), with HDL-3 subfraction (p = 0.0229), and intermediate density lipoprotein-A (IDL-A) (p = 0.038). A significant correlation between increased diastolic blood pressure and HDL lipoprotein levels (p = 0.0454) was only observed.

CONCLUSIONS

Obtained results indicating correlation between total HDL levels and HDL-3 subfraction concentration (for systolic BP) and the tendency to develop hypertension.

Risk of cardiovascular events in patients with non-alcoholic fatty liver disease: a systematic review and meta-analysis

AIMS 

Non-alcoholic fatty liver disease (NAFLD) is a highly prevalent disease and has been repeatedly associated with an increased risk of cardiovascular disease. However, the extent of such association is unclear. We conducted a systematic review and meta-analysis of the literature to evaluate the risk of myocardial infarction (MI), ischaemic stroke (IS), atrial fibrillation (AF), and heart failure (HF) in NAFLD patients.

METHODS AND RESULTS 

According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we systematically searched PubMed and EMBASE, from inception to 6 March 2021, and included all studies reporting the incidence of MI, IS, AF, and HF in patients with and without NAFLD. Random-effect fmodels were used to estimate pooled odds ratio (OR), 95% confidence intervals (CI), and 95% prediction intervals (PI); subgroup analyses, meta-regressions, and sensitivity analyses were additionally performed. Among 3254 records retrieved from literature, 20 studies were included. Non-alcoholic fatty liver disease was associated with an increased risk of MI (OR: 1.66, 95% CI: 1.39-1.99, 95% PI: 0.84-3.30), IS (OR: 1.41, 95% CI: 1.29-1.55, 95% PI 1.03-1.93), AF (OR: 1.27, 95% CI: 1.18-1.37, 95% PI: 1.07-1.52), and HF (OR: 1.62, 95% CI: 1.43-1.84, 95% CI: 1.04-2.51). We identified significant subgroup differences according to geographical location, study design, NAFLD definition, and risk of bias; meta-regressions identified mean age, male sex, and study-level characteristics as potential moderators of the risk of MI and IS.

CONCLUSIONS 

Non-alcoholic fatty liver disease was associated with increased risk of MI, IS, AF, and HF. Age, sex, and study characteristics may moderate the strength of this association. Further studies are required to evaluate specific cardiovascular prevention strategies in patients with NAFLD.

Pathophysiological Molecular Mechanisms of Obesity: A Link between MAFLD and NASH with Cardiovascular Diseases

Obesity is now a worldwide epidemic ensuing an increase in comorbidities’ prevalence, such as insulin resistance, type 2 diabetes (T2D), metabolic dysfunction-associated fatty liver disease (MAFLD), nonalcoholic steatohepatitis (NASH), hypertension, cardiovascular disease (CVD), autoimmune diseases, and some cancers, CVD being one of the main causes of death in the world. Several studies provide evidence for an association between MAFLD and atherosclerosis and cardio-metabolic disorders, including CVDs such as coronary heart disease and stroke. Therefore, the combination of MAFLD/NASH is associated with vascular risk and CVD progression, but the underlying mechanisms linking MAFLD/NASH and CVD are still under investigation. Several underlying mechanisms may probably be involved, including hepatic/systemic insulin resistance, atherogenic dyslipidemia, hypertension, as well as pro-atherogenic, pro-coagulant, and pro-inflammatory mediators released from the steatotic/inflamed liver. MAFLD is strongly associated with insulin resistance, which is involved in its pathogenesis and progression to NASH. Insulin resistance is a major cardiovascular risk factor in subjects without diabetes. However, T2D has been considered the most common link between MAFLD/NASH and CVD. This review summarizes the evidence linking obesity with MAFLD, NASH, and CVD, considering the pathophysiological molecular mechanisms involved in these diseases. We also discuss the association of MAFLD and NASH with the development and progression of CVD, including structural and functional cardiac alterations, and pharmacological strategies to treat MAFLD/NASH and cardiovascular prevention.

Evolution of Fatty Liver Disease and Relationship With Lipoproteins and Clinical Outcomes in Hepatitis B/Human Immunodeficiency Virus Coinfection

BACKGROUND

Fatty liver disease (FLD) and hepatitis B virus (HBV) infection occur commonly in human immunodeficiency virus (HIV). FLD resolution is associated with improvement in lipoproteins in HIV-uninfected patients. We evaluated changes in FLD in an HBV/HIV-coinfected cohort.

METHODS

One hundred eight HBV/HIV-coinfected adults with baseline liver biopsies were followed every 24 weeks (median, 166 weeks) and 60 had follow-up biopsies. Baseline FLD categories (none, ≥5% steatosis, steatohepatitis), their change, and relationships with clinical and lipid/lipoprotein parameters were explored using multivariable modeling.

RESULTS

Median age was 50 years, and 93% were male. At baseline 30% had FLD. With control for lipid-lowering medications and body mass index, low-density lipoprotein (LDL) cholesterol (LDL-C), LDL particle concentration (LDL-P), and apolipoprotein B (apoB) decreased and adiponectin increased over time (all P < .05); On follow-up (vs baseline), there was no significant difference in FLD category (P = .85); 60% remained without FLD, 17% had unchanged, 12% worsening, and 12% improved FLD. Baseline low-density lipoproteins (LDL-C, LDL-P, small LDL-P) and apoB appeared highest in those with unchanged FLD status (all P < .05). No associations between changes in FLD across follow-up (worsening/improvement vs unchanged) and lipid/lipoproteins changes were identified.

CONCLUSIONS

In this cohort, there was no significant change in FLD prevalence over a relatively short timeframe. Baseline atherogenic lipids appeared highest in those with persistent steatosis or steatohepatitis, suggesting potentially increased cardiovascular risk in this group, but an independent relationship between individual-level change in FLD status and lipid/lipoprotein levels across follow-up was not observed.

Interplay between Heart Disease and Metabolic Steatosis: A Contemporary Perspective

The liver-heart axis is a growing field of interest owing to rising evidence of complex bidirectional interplay between the two organs. Recent data suggest non-alcoholic fatty liver disease (NAFLD) has a significant, independent association with a wide spectrum of structural and functional cardiac diseases, and seems to worsen cardiovascular disease (CVD) prognosis. Conversely, the effect of cardiac disease on NAFLD is not well studied and data are mostly limited to cardiogenic liver disease. We believe it is important to further investigate the heart-liver relationship because of the tremendous global health and economic burden the two diseases pose, and the impact of such investigations on clinical decision making and management guidelines for both diseases. In this review, we summarize the current knowledge on NAFLD diagnosis, its systemic manifestations, and associations with CVD. More specifically, we review the pathophysiological mechanisms that govern the interplay between NAFLD and CVD and evaluate the relationship between different CVD treatments and NAFLD progression.

Pasta Supplemented with Opuntia ficus-indica Extract Improves Metabolic Parameters and Reduces Atherogenic Small Dense Low-Density Lipoproteins in Patients with Risk Factors for the Metabolic Syndrome: A Four-Week Intervention Study

Food supplementation with Opuntia ficus-indica (OFI) has been associated with a significant reduction in total cholesterol, body fat, hyperglycemia and blood pressure. Since OFI may also have antioxidant and anti-atherogenic properties, we hypothesized that its supplementation might reduce atherogenic lipoproteins, including small, dense low-density lipoproteins (sdLDL). Forty-nine patients (13 men and 36 women, mean age: 56 ± 5 years) with one or two criteria for the metabolic syndrome weekly consumed 500 g of pasta supplemented with 3% OFI extract (30% of insoluble polysaccharides with high antioxidant power) for 1 month. The full LDL subclass profile was assessed by gel electrophoresis (Lipoprint, Quantimetrix, Redondo Beach, CA, USA). After 1 month of pasta supplementation, waist circumference (p = 0.0297), plasma glucose (p < 0.0001), triglycerides (p = 0.0137), plasma creatinine (p = 0.0244), urea and aspartate transaminase (p < 0.0001 for each) significantly decreased. A percentage increase in larger, less atherogenic LDL-1 (p = 0.0002), with a concomitant reduction in smaller, denser LDL-2 (p < 0.0001) and LDL-3 (p = 0.0004), were found. LDL-4 and-5 decreased, although not significantly. This is the first intervention study suggesting that pasta enriched with an OFI extract may have beneficial effects on some metabolic parameters and the LDL particle sizes, reducing atherogenic sdLDL. Future studies will help to establish if these findings impact cardiovascular outcomes.

Daily Use of Extra Virgin Olive Oil with High Oleocanthal Concentration Reduced Body Weight, Waist Circumference, Alanine Transaminase, Inflammatory Cytokines and Hepatic Steatosis in Subjects with the Metabolic Syndrome: A 2-Month Intervention Study

Extra virgin olive oil (EVOO) intake is associated with reduced cardiovascular risk, and its phenolic compound oleocanthal (OC) has anti-oxidant and anti-inflammatory properties. The cardiometabolic effects of EVOO with a high OC concentration have not been fully elucidated. We administered EVOO with a high OC concentration daily to 23 subjects with the metabolic syndrome (MetS) and hepatic steatosis (15 men and 8 women, age: 60 ± 11 years) for 2 months. Anthropometric data, metabolic parameters, hepatic steatosis (by fatty liver index, FLI), abdominal fat distribution (by ultrasound), and pro- and anti-inflammatory cytokines were assessed before and after the intervention. EVOO supplementation was associated with a reduction in body weight, waist circumference, body mass index (BMI), alanine transaminase and FLI, as well as interleukin (IL)-6, IL-17A, tumor necrosis factor-α and IL-1B, while IL-10 increased. Maximum subcutaneous fat thickness (SFT max) also increased, with a concomitant decrease in the ratio of visceral fat layer thickness/SFT max. Correlation analysis revealed positive associations between changes in body weight and BMI and those in SFT max, along with an inverse association between changes in IL-6 and those in SFT max. In conclusion, ingestion of EVOO with a high OC concentration had beneficial effects on metabolic parameters, inflammatory cytokines and abdominal fat distribution in MetS subjects with hepatic steatosis, a category of patients at high cardiometabolic risk.

Correlation between the small dense LDL level and nonalcoholic fatty liver disease: Possibility of a new biomarker

Small dense low-density lipoprotein (sdLDL) is a distinct low-density lipoprotein (LDL) cholesterol subclass that has been reported to be associated with metabolic disease. On the other hand, the relationship between the sdLDL level and the nonalcoholic fatty liver disease (NAFLD) severity is unclear. In this study, the sdLDL level was measured in patients with NAFLD to assess its potential as a biomarker for evaluating NAFLD. One hundred and twenty-six patients diagnosed with NAFLD at a single referral hospital from January 2018 to August 2019 were enrolled. The lipoprotein profile was analyzed from a blood test of NAFLD patients, and transient elastography (TE, Fibroscan) was performed to evaluate the degree of NAFLD. Among the 126 patients, 83 patients that could confirm the lipoprotein profile and TE results were finally enrolled in the study. The controlled attenuation parameter (CAP) value obtained from TE did not show any correlation with the total cholesterol, LDL. But, the sdLDL level showed a significant positive correlation with the CAP value (r = 0.237, P = .031), and the sdLDL/LDL ratio also showed a significant positive correlation with the CAP value (r = 0.235, P = .032). The liver stiffness (LS) measured by TE and the sdLDL level were positively correlated in patients with NAFLD (rho = 0.217, P = .049). The sdLDL/LDL ratio also showed a significant positive correlation with the LS value (rho = 0.228, P = .038). In addition, the fatty liver index also showed a significant positive correlation with the sdLDL/LDL ratio (r = 0.448, P = .000). In this study, the sdLDL level measured by a blood test of NAFLD patients showed a positive correlation with the CAP value and LS, which indicate the degree of hepatic steatosis and fibrosis. These results suggest the possibility of the sdLDL level as a new biomarker of NAFLD, but further studies will be needed to support these results.

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.

Gamma-glutamyl transferase and cardiovascular risk in nonalcoholic fatty liver disease: The Gut and Obesity Asia initiative

BACKGROUND

Gamma-glutamyl transferase (GGT) is associated with the risk of cardiovascular disease (CVD) in the general population.

AIM

To identify the association of baseline GGT level and QRISK2 score among patients with biopsy-proven nonalcoholic fatty liver disease (NAFLD).

METHODS

This was a retrospective study involving 1535 biopsy-proven NAFLD patients from 10 Asian centers in 8 countries using data collected by the Gut and Obesity in Asia (referred to as "GO ASIA") workgroup. All patients with available baseline GGT levels and all 16 variables for the QRISK2 calculation (QRISK2-2017; developed by researchers at the United Kingdom National Health Service; https://qrisk.org/2017/; 10-year cardiovascular risk estimation) were included and compared to healthy controls with the same age, sex, and ethnicity. Relative risk was reported. QRISK2 score > 10% was defined as the high-CVD-risk group. Fibrosis stages 3 and 4 (F3 and F4) were considered advanced fibrosis.

RESULTS

A total of 1122 patients (73%) had complete data and were included in the final analysis; 314 (28%) had advanced fibrosis. The median age (interquartile range [IQR]) of the study population was 53 (44-60) years, 532 (47.4%) were females, and 492 (43.9%) were of Chinese ethnicity. The median 10-year CVD risk (IQR) was 5.9% (2.6-10.9), and the median relative risk of CVD over 10 years (IQR) was 1.65 (1.13-2.2) compared to healthy individuals with the same age, sex, and ethnicity. The high-CVD-risk group was significantly older than the low-risk group (median [IQR]: 63 [59-67] vs 49 [41-55] years; P < 0.001). Higher fibrosis stages in biopsy-proven NAFLD patients brought a significantly higher CVD risk (P < 0.001). Median GGT level was not different between the two groups (GGT [U/L]: Median [IQR], high risk 60 [37-113] vs low risk 66 [38-103], P = 0.56). There was no correlation between baseline GGT level and 10-year CVD risk based on the QRISK2 score (r = 0.02).

CONCLUSION

The CVD risk of NAFLD patients is higher than that of healthy individuals. Baseline GGT level cannot predict CVD risk in NAFLD patients. However, advanced fibrosis is a predictor of a high CVD risk.

Metabolic Inflammation-A Role for Hepatic Inflammatory Pathways as Drivers of Comorbidities in Nonalcoholic Fatty Liver Disease?

Nonalcoholic fatty liver disease (NAFLD) is a global and growing health concern. Emerging evidence points toward metabolic inflammation as a key process in the fatty liver that contributes to multiorgan morbidity. Key extrahepatic comorbidities that are influenced by NAFLD are type 2 diabetes, cardiovascular disease, and impaired neurocognitive function. Importantly, the presence of nonalcoholic steatohepatitis and advanced hepatic fibrosis increase the risk for systemic comorbidity in NAFLD. Although the precise nature of the crosstalk between the liver and other organs has not yet been fully elucidated, there is emerging evidence that metabolic inflammation-in part, emanating from the fatty liver-is the engine that drives cellular dysfunction, cell death, and deleterious remodeling within various body tissues. This review describes several inflammatory pathways and mediators that have been implicated as links between NAFLD and type 2 diabetes, cardiovascular disease, and neurocognitive decline.

Fetuin-A and Fetuin-B in Non-Alcoholic Fatty Liver Disease: A Meta-Analysis and Meta-Regression

The magnitude of the effect of fetuin-A and fetuin-B on non-alcoholic fatty liver disease (NAFLD) remains undefined. Therefore, the aim of this study was to synthesize previous findings to obtain a reliable estimation of this relationship. This study was registered in PROSPERO with the number CRD42019126314. Studies published not later than March 2019, examining the relationship between fetuin-A, fetuin-B, and NAFLD, were identified by a systematic search in the electronic databases of the Web of Science, PubMed, Embase, and Cochrane Library. Pooled estimates of standardized mean difference (SMD), calculated using the random-effects model in a meta-analysis, were applied to estimate the strength of the association between fetuin-A, fetuin-B, and NAFLD. Thirty publications were identified and analyzed based on specified inclusion criteria. Collectively, they consisted of 3800 NAFLD participants and 3614 controls. Compared with the controls, significant higher values of the fetuin-A (SMD = 0.83, 95% CI: 0.59 to 1.07, Z = 6.82, p < 0.001) and fetuin-B (SMD = 0.18, 95% CI: 0.02 to 0.33, Z = 2.27, p = 0.023) were observed in NAFLD patients. Meanwhile, in the subgroup analysis, the effect value of fetuin-A in the NASH group was significantly higher than that in the NAFL group (p = 0.036). The findings of this study suggest that elevated fetuin-A and fetuin-B may independently indicate the occurrence of NAFLD. Nevertheless, further research is needed to confirm these results.

Nonalcoholic Fatty Liver Disease and the Heart: JACC State-of-the-Art Review

Nonalcoholic fatty liver disease (NAFLD) and cardiovascular disease (CVD) are both manifestations of end-organ damage of the metabolic syndrome. Through multiple pathophysiological mechanisms, CVD and NAFLD are associated with each other. Systemic inflammation, endothelial dysfunction, hepatic insulin resistance, oxidative stress, and altered lipid metabolism are some of the mechanisms by which NAFLD increases the risk of CVD. Patients with NAFLD develop increased atherosclerosis, cardiomyopathy, and arrhythmia, which clinically result in cardiovascular morbidity and mortality. Defining the mechanisms linking these 2 diseases offers the opportunity to further develop targeted therapies. The aim of this comprehensive review is to examine the association between CVD and NAFLD and discuss the overlapping management approaches.

Loss of hepatic PPARα promotes inflammation and serum hyperlipidemia in diet-induced obesity

Agonists for PPARα are used clinically to reduce triglycerides and improve high-density lipoprotein (HDL) cholesterol levels in patients with hyperlipidemia. Whether the mechanism of PPARα activation to lower serum lipids occurs in the liver or other tissues is unknown. To determine the function of hepatic PPARα on lipid profiles in diet-induced obese mice, we placed hepatocyte-specific peroxisome proliferator-activated receptor-α (PPARα) knockout (Ppara^HepKO) and wild-type (Ppara^fl/fl) mice on high-fat diet (HFD) or normal fat diet (NFD) for 12 wk. There was no significant difference in weight gain, percent body fat mass, or percent body lean mass between the groups of mice in response to HFD or NFD. Interestingly, the Ppara^HepKO mice on HFD had worsened hepatic inflammation and a significant shift in the proinflammatory M1 macrophage population. These changes were associated with higher hepatic fat mass and decreased hepatic lean mass in the Pparα^HepKO on HFD but not in NFD as measured by Oil Red O and noninvasive EchoMRI analysis (31.1 ± 2.8 vs. 20.2 ± 1.5, 66.6 ± 2.5 vs. 76.4 ± 1.5%, P < 0.05). We did find that this was related to significantly reduced peroxisomal gene function and lower plasma β-hydroxybutyrate in the Ppara^HepKO on HFD, indicative of reduced metabolism of fats in the liver. Together, these provoked higher plasma triglyceride and apolipoprotein B100 levels in the Ppara^HepKO mice compared with Ppara^fl/fl on HFD. These data indicate that hepatic PPARα functions to control inflammation and liver triglyceride accumulation that prevent hyperlipidemia.

The hepatokine Tsukushi is released in response to NAFLD and impacts cholesterol homeostasis

Nonalcoholic fatty liver disease (NAFLD) prevails in obesity and is linked to several health complications including dyslipidemia and atherosclerosis. How exactly NAFLD induces atherogenic dyslipidemia to promote cardiovascular diseases is still elusive. Here, we identify Tsukushi (TSK) as a hepatokine induced in response to NAFLD. We show that both endoplasmic reticulum stress and inflammation promote the expression and release of TSK in mice. In humans, hepatic TSK expression is also associated with steatosis, and its circulating levels are markedly increased in patients suffering from acetaminophen-induced acute liver failure (ALF), a condition linked to severe hepatic inflammation. In these patients, elevated blood TSK levels were associated with decreased transplant-free survival at hospital discharge, suggesting that TSK could have a prognostic significance. Gain- and loss-of-function studies in mice revealed that TSK impacts systemic cholesterol homeostasis. TSK reduces circulating HDL cholesterol, lowers cholesterol efflux capacity, and decreases cholesterol-to-bile acid conversion in the liver. Our data identify the hepatokine TSK as a blood biomarker of liver stress that could link NAFLD to the development of atherogenic dyslipidemia and atherosclerosis.

Adiposity May Moderate the Link Between Choline Intake and Non-alcoholic Fatty Liver Disease

Background: In animal models, histological and biochemical changes are observed in response to choline deficiency. It is unclear whether dietary choline is linked to non-alcoholic fatty liver disease (NAFLD). Objective: We examined the link among liver tests, fatty liver index (FLI), and choline consumption. Furthermore, we evaluated the impact of adiposity on this association. Method: The National Health and Nutrition Examination Survey (NHANES) was used to obtain data on choline intake and liver function biomarkers. Masked variance and weighting methodology were performed to account for the complex NHANES data. Results: Of the 20,643 participants, 46.8% were men and 45.6% had NAFLD (defined as United States FLI ≥30). In a fully adjusted model (for demographic, dietary, and clinical factors), a significant negative association was found between FLI and choline consumption (β = -0.206, p < 0.001). Participants in the highest quartile (Q4) of choline intake had a 14% lower risk of NAFLD compared with those in the first quartile (Q1). This link was stronger for postmenopausal women; women in Q4 had a 26% lower risk of NAFLD compared with those in Q1. Body mass index (BMI) strongly moderated the link between FLI and choline intake. For example, when choline consumption increased from low (272 mg/d) to high (356 mg/d), FLI decreased from 79.3 to 74.1 in the low BMI category (mean BMI = 22.1 kg/m²) and from 32.1 to 20.6 in the high BMI category (mean BMI =35.9 kg/m²). Conclusions: Our results suggest the presence of a reverse significant association between choline intake and risk of NAFLD. Furthermore, BMI was shown to mediate this relationship since changes in FLI, in relation to choline consumption, were more pronounced in participants with a higher BMI.

Bacterial infections are associated with cardiovascular disease in Iran: a meta-analysis

INTRODUCTION

The present study aimed to assess the prevalence and association of various bacterial infections with cardiovascular disease (CVD) in Iran.

MATERIAL AND METHODS

An electronic search was performed using related keywords in the national and international databases up to June 30, 2017. Out of the 1807 articles found on the associations between bacterial infections and CVD, 20 relevant studies were selected for the meta-analysis.

RESULTS

The prevalence of bacterial infections was higher in case groups compared with the control groups. Odds ratios for assessing the association between Chlamydia pneumonia infection and CVD based on PCR, IgG and IgA tests were 7.420 (95% CI: 3.088-17.827), 3.710 (95% CI: 1.361-10.115) and 2.492 (95% CI: 1.305-4.756), respectively. Moreover, the calculated odds ratio for Mycoplasma pneumonia infection was 1.815 (95% CI: 0.973-3.386). For Helicobacter pylori infection, odds ratios based on IgG and IgA tests were 3.160 (95% CI: 1.957-5.102) and 0.643 (95% CI: 0.414-0.999), respectively.

CONCLUSIONS

The present meta-analysis suggested that there was a significant association between H. pylori, C. pneumonia and M. pneumonia infections and CVD in Iran. These findings confirm the potential role of bacterial infections as predisposing factors for CVD.

Cardio-Metabolic Disorders in Non-Alcoholic Fatty Liver Disease

With the progressive epidemics of obesity, non-alcoholic fatty liver disease (NAFLD) has become the most common cause of chronic liver disease in adults and children. The increasing prevalence and incidence of NAFLD with advanced fibrosis is concerning because patients appear to experience higher non-liver-related morbidity and mortality than the general population. Recent clinical evidence suggests that NAFLD is directly associated with an increased risk of cardio-metabolic disorders. This mini review describes briefly the current understanding of the pathogenesis of NAFLD, summarizing the link between NAFLD and cardio-metabolic complications, focusing mainly upon ischemic stroke, type 2 diabetes mellitus (DM), hypertension, chronic kidney disease (CKD) and cardiac arrhythmias. In addition, it describes briefly the current understanding of the pathogenesis of NAFLD.

Relationship between resolution of non-alcoholic steatohepatitis and changes in lipoprotein sub-fractions: a post-hoc analysis of the PIVENS trial

BACKGROUND

Dyslipidaemia is frequent in non-alcoholic steatohepatitis (NASH); however, it is unclear if improvement in liver histology is associated with favourable changes in cardiovascular disease (CVD) risk.

AIMS

To evaluate the relationship of NASH resolution and lipoprotein subfraction levels, markers of endothelial dysfunction, and macrophage activation.

METHODS

One hundred and seventeen individuals with NASH who participated in the Pioglitazone vs Vitamin E vs Placebo for the Treatment of Nondiabetic Patients with NASH (PIVENS) trial with paired liver biopsies and serum samples available at baseline and after 96 weeks of treatment were included. Participants in the PIVENS trials received vitamin E, pioglitazone, or placebo for 96 weeks. Lipoprotein subfraction levels, intracellular adhesion molecule 1 (ICAM-1), vascular cellular adhesion molecule 1 (VCAM-1), E-selectin, and sCD163 levels were assessed at baseline and week 96 and their relationship with NASH resolution was examined.

RESULTS

Fifty-seven individuals had NASH resolution and 60 individuals did not have resolution of NASH. NASH resolution was associated with favourable changes in lipoprotein subfraction levels compared to those without NASH resolution. Individuals with resolution of NASH had a significantly increased mean peak LDL diameter (ratio of geometric means [96 weeks vs baseline] 1.007 vs 0.996, P = 0.004), and higher frequency of LDL phenotype A (58% vs 33%, P = 0.003) at week 96, after adjustment for relevant co-variates including treatment group. No differences in VCAM, ICAM, E-selectin, or sCD163 levels by NASH resolution were found.

CONCLUSIONS

NASH resolution is associated with favourable changes in a subset of serum lipoprotein levels. More studies are warranted to understand if these favourable changes are associated with decreased risk of CVD.

Multifocal fatty liver disease, insulin resistance and carotid atherosclerosis: exploring the interrelated relationship

Introduction: Multifocal fatty liver infiltrations are not uncommon ultrasonographic finding; they are explained by the presence of aberrant vascular supply independent of the portal circulation or insulin resistance. Aim: To study the significance of this ultrasonographic finding. Methods: A study group (n = 96) with multifocal fatty liver and two control groups: healthy subjects (n = 100) and patients with diffuse fatty liver disease (n = 100) were enrolled. They were tested for fasting blood glucose, lipid profile, transaminases, serum insulin, glycated hemoglobin, Homeostatic Model Assessment of Insulin Resistance, high-sensitivity C-reactive protein and liver stiffness in Fibroscan. Results: Patients with multifocal fatty liver showed a statistically significant higher values of serum transaminases, markers of insulin resistance, high-sensitivity C-reactive protein, and neutrophil lymphocyte ratio (p <0.05). Lipid profile parameters were significantly higher (p <0.05). Mean liver stiffness (9.8 ± 1.2 kPa) and carotid intima media thickness (1.16 ± 0.2 mm) were significantly higher when compared to healthy subjects and patients with diffuse fatty liver disease. Independent predictors of insulin resistance and premature carotid atherosclerosis in patients with multifocal fatty liver disease were: serum gamma-glutamyl transferase (odds ratio 1.69), high-sensitivity C-reactive protein (odds ratio 1.62), uric acid (odds ratio 1.55), very low-density lipoprotein (odds ratio 1.74), total cholesterol/high-density lipoprotein (odds ratio 1.58) and severity of liver stiffness measured by Fibroscan (odds ratio 1.9). Conclusions: Multifocal fatty liver is an aggressive form of nonalcoholic fatty liver disease and should be considered a radiological sign of insulin resistance that needs special attention and management.

Introduction: Multifocal fatty liver infiltrations are not uncommon ultrasonographic finding; they are explained by the presence of aberrant vascular supply independent of the portal circulation or insulin resistance. Aim: To study the significance of this ultrasonographic finding. Methods: A study group (n = 96) with multifocal fatty liver and two control groups: healthy subjects (n = 100) and patients with diffuse fatty liver disease (n = 100) were enrolled. They were tested for fasting blood glucose, lipid profile, transaminases, serum insulin, glycated hemoglobin, Homeostatic Model Assessment of Insulin Resistance, high-sensitivity C-reactive protein and liver stiffness in Fibroscan. Results: Patients with multifocal fatty liver showed a statistically significant higher values of serum transaminases, markers of insulin resistance, high-sensitivity C-reactive protein, and neutrophil lymphocyte ratio (p <0.05). Lipid profile parameters were significantly higher (p <0.05). Mean liver stiffness (9.8 ± 1.2 kPa) and carotid intima media thickness (1.16 ± 0.2 mm) were significantly higher when compared to healthy subjects and patients with diffuse fatty liver disease. Independent predictors of insulin resistance and premature carotid atherosclerosis in patients with multifocal fatty liver disease were: serum gamma-glutamyl transferase (odds ratio 1.69), high-sensitivity C-reactive protein (odds ratio 1.62), uric acid (odds ratio 1.55), very low-density lipoprotein (odds ratio 1.74), total cholesterol/high-density lipoprotein (odds ratio 1.58) and severity of liver stiffness measured by Fibroscan (odds ratio 1.9). Conclusions: Multifocal fatty liver is an aggressive form of nonalcoholic fatty liver disease and should be considered a radiological sign of insulin resistance that needs special attention and management.

Ideal cardiovascular health associated with fatty liver: Results from a multi-ethnic survey

BACKGROUND AND AIMS

Little is known about the role of liver enzymes as predictors of non-liver-related morbidity and mortality. The ideal cardiovascular health (CVH) score proposed by the American Heart Association (AHA) can be used to predict mortality and morbidity. We investigated the association of the CVH score with liver enzymes and the risk of non-alcoholic fatty liver disease (NAFLD) among US adults.

METHODS

By using the National Health and Nutrition Examination Survey database (cross-sectional), the CVH score was calculated as meeting ideal levels of the following components: 4 behaviors (smoking, body mass index, physical activity and diet adherence) and 3 factors (total cholesterol, blood pressure and fasting glucose).

RESULTS

Individuals with a higher CVH score ("better CVH") had a more favorable profile of liver biomarkers. Adjusted (for age, gender, race, poverty to income ratio, education, marital status and alcohol intake) linear regression indicated significant and negative associations between liver biomarkers and CVH score: (β = -0.069, p < 0.001) for alanine aminotransferase, (β = -0.095, p < 0.001), aspartate aminotransferase, (β = -0.067, p < 0.001), alkaline phosphatase and (β = -0.125, p < 0.001) and fatty liver index. In the logistic regression, with the same confounders, individuals with a higher CVH score had 12% less likelihood of NAFLD compared with those with a lower score. Furthermore, each CVH metric separately was inversely linked to the risk of NAFLD.

CONCLUSIONS

For the first time among US adults, our findings shed light on the role CVH on liver biomarkers.

A higher flavonoid intake is associated with less likelihood of nonalcoholic fatty liver disease: results from a multiethnic study

Limited information exists on the impact of flavonoid intake on nonalcoholic fatty liver disease (NAFLD). We evaluated the link between flavonoid intake, liver tests and risk of NAFLD in a randomly selected sample of US adults (from the National Health and Nutrition Examination Survey, NHANES, 2005-2010). Of the 17,685 participants, 46.9% were men and 45.4% had NAFLD. NAFLD patients had a significantly lower mean flavonoid intake than healthy individuals (111.3±3.6 vs. 201.3±2.3 mg/d, respectively; P<.001). Fatty liver index (FLI) and serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were significantly higher in the first tertile (T1) of flavonoid intake compared with the highest tertile (T3: with the highest flavonoid intake) (FLI: 67.1 vs. 36.2, AST: 31.2 VS 26.8 U/L and, ALT: 34.2 vs. 24.2 U/L, respectively; P<.001 for all comparisons). Adjusted linear regression displayed significant and negative associations between FLI, AST, ALT and flavonoid intake (P<.001 for all comparisons). Multivariable logistic regression showed that the risk for NAFLD significantly decreased as flavonoid intake tertiles increased in a stepwise manner (odds ratio: 0.81, 95% confidence interval: 0.78-0.86). Moderation analysis revealed that C-reactive protein (CRP) strongly modulated the impact of flavonoid intake on FLI; participants with higher CRP levels benefited less from flavonoid intake compared with those with lower CRP concentrations. In conclusions, our results suggest a reverse significant association between flavonoid consumption, liver tests and the risk for NAFLD. Furthermore, CRP was shown to essentially moderate this relationship. These findings support recommendations for consumption of flavonoid-rich foods to prevent cardiometabolic diseases.

Association of non-alcoholic fatty liver disease with cardiovascular disease and subclinical atherosclerosis

Non-alcoholic fatty liver disease (NAFLD) refers to fatty infiltration of liver in the absence of significant alcohol intake, use of steatogenic medication, or hereditary disorders. It is a common cause of chronic liver disease with a worldwide estimated prevalence ranging from 6.3% to 33%. The NAFLD is considered a hepatic manifestation of the metabolic syndrome. Insulin resistance and increased oxidative stress are central to pathogenesis of NAFLD, and risk factors include metabolic syndrome, diabetes mellitus, obesity, lack of physical activity, smoking, and high fat diet. NAFLD is associated with higher mortality as compared to the general population with cardiovascular disease being the most common cause of death. The NAFLD is associated with a higher prevalence of subclinical atherosclerosis as evidenced by odds of higher coronary artery calcification, higher average and maximum carotid intima-media thickness. It is also associated with stiff arteries as evidenced by higher cardio-ankle vascular index and higher brachial-ankle pulse wave velocity. Increasing evidence has linked NAFLD with atherosclerotic cardiovascular diseases. The NAFLD is associated with a higher prevalence of coronary artery disease (CAD), more severe CAD, poor coronary collateral development, and higher incidence of coronary events. The NAFLD is also associated with ischemic stroke. Studies have shown that the association between NAFLD and atherosclerotic cardiovascular diseases is independent of shared risk factors.

The impact of non-alcoholic fatty liver disease and metabolic syndrome on the progression of coronary artery calcification

It is unclear whether non-alcoholic fatty liver disease (NAFLD) is an independent risk factor for cardiovascular disease. We examined the independent impact of NAFLD on the progression of the coronary artery calcification (CAC) score, a well-known marker of atherosclerosis progression. We examined 1,173 asymptomatic participants who underwent repeated CAC score measurement during routine health examinations. The subjects were categorised into four groups based on the presence (+) or absence (−) of NAFLD and metabolic syndrome (MetS). The progression of CAC score was defined as either incident CAC in a CAC-free population at baseline or an increase of ≥2.5 units between the baseline and the final square roots of the CAC scores of participants with detectable CAC at baseline. CAC progression was seen in 18.6% (98/526), 28.3% (77/272), 29.1% (30/103) and 32.0% (87/272) of the subjects with NAFLD(−)/MetS(−), NAFLD(+)/MetS(−), NAFLD(−)/MetS(+) and NAFLD(+)/MetS(+), respectively. The subjects with NAFLD(+)/MetS(+) and NAFLD(+)/MetS(−) had a significantly higher risk of CAC progression than those with NAFLD(−)/MetS(−) (multivariate-adjusted odds ratio [OR]: 1.76; 95% confidence interval [CI]: 1.18–2.62 and multivariate-adjusted OR: 1.53, 95% CI: 1.05–2.23, respectively). NAFLD is an independent risk factor for CAC progression, irrespective of the presence of MetS.

Impaired HDL cholesterol efflux capacity in patients with non-alcoholic fatty liver disease is associated with subclinical atherosclerosis

Non-alcoholic fatty liver disease (NAFLD) is associated with a substantial increased risk of atherosclerotic cardiovascular disease (ASCVD), which is partly related to dyslipidemia and low HDL-C level. The cardioprotective activity of HDL in the body is closely connected to its role in promoting cholesterol efflux, which is determined by cholesterol efflux capacity (CEC). Hitherto, the role of HDL, as defined by CEC has not been assessed in NAFLD patients. In this research study, we present the results of a study of cAMP-treated J774 CEC and THP-1 macrophage CEC in ApoB-depleted plasma of 55 newly diagnosed NAFLD patients and 30 controls. Circulating levels of ApoA-I, ApoB, preβ-HDL, plasma activity of CETP, PLTP, LCAT and carotid intima-media thickness (cIMT) were estimated. cAMP-treated J774 and THP-1 macrophage CEC were found to be significantly lower in NAFLD patients compared to controls (P < 0.001 and P = 0.003, respectively). In addition, it was discovered that both ApoA-I and preβ1-HDL were significantly lower in NAFLD patients (P < 0.001). Furthermore, cAMP-treated J774 CEC showed independent negative correlation with cIMT, as well as the presence of atherosclerotic plaque in NAFLD patients. In conclusion, our findings showed that HDL CEC was suppressed in NAFLD patients, and impaired cAMP-treated J774 CEC was an independent risk factor for subclinical atherosclerosis in NAFLD patients, suggesting that impaired HDL functions as an independent risk factor for atherosclerosis in NAFLD.

Small, dense LDL: an update

PURPOSE OF REVIEW

In this review, we summarize the latest findings on small, dense LDL (sdLDL) atherogenic particles, including their associations with other biomarkers.

RECENT FINDINGS

Increased sdLDL levels have been reported not only in different metabolic disorders such as diabetes, obesity and metabolic syndrome, but also in patients with rheumatoid and psoriatic arthritis as well as hypothyroidism. A wide range of lipid-lowering, as well as other drug classes, including novel antidiabetic agents and nutraceuticals, exert favourable effects on these atherogenic particles. The 'gold standard' methodology for the assessment of sdLDL has not been established yet. However, the association between sdLDL and several biomarkers could facilitate their assessment.

SUMMARY

Estimation of sdLDL in daily clinical practice may help with the identification of patients at high cardiovascular risk and further contribute in directing specific interventions to prevent and/or decrease such risk.

Correlation between ultrasound-diagnosed non-alcoholic fatty liver and periodontal condition in a cross-sectional study in Japan

This cross-sectional study investigated the relationship between periodontal condition and ultrasound-diagnosed non-alcoholic fatty liver disease (NAFLD) in a Japanese oral health check population. A total of 1226 consecutive participant were enrolled in the study. Abdominal ultrasonography was applied to diagnose NAFLD. Of the study participants, 339 (27.7%) had ultrasonography-diagnosed NAFLD. The participants with NAFLD had a significantly higher prevalence of probing pocket depth (PPD) ≥ 4 mm (86.7%) than those without NAFLD (72.9%) (p < 0.05). After adjusting for gender, age, Brinkman index, regular exercise habits, body mass index, number of teeth present, presence of periodontitis, blood pressure, and serum parameters, there was a statistically significant difference in the adjusted odds ratios of having PPD ≥ 4 mm for NAFLD (Odds ratio = 1.881, 95% confidence interval 1.184–2.987, p < 0.01). Having PPD ≥ 4 mm may be a risk factor for ultrasound-diagnosed NAFLD in this cross-sectional study of a Japanese oral health check population.

Implication of liver enzymes on incident cardiovascular diseases and mortality: A nationwide population-based cohort study

Although liver enzymes, such as γ-glutamyltransferase (GGT), alanine aminotransferase (ALT), and aspartate aminotransferase (AST), have recently been suggested as risk factors for cardiovascular diseases (CVD), impact on mortality after myocardial infarction (MI) or ischemic stroke (IS) was not previously examined. Using a population-based, nationwide cohort database, we explored the implication of GGT and aminotransferases on the development of CVD and all-cause mortality during a median 9.1 years of follow-up. Among 16,624,006 Korean adults, both GGT and aminotransferases exhibited a positive relationship with MI, IS, and mortality in a multivariate adjusted model. ALT and AST showed U-shaped associations with mortality, whereas GGT showed a positive linear relationship with mortality. The risk of 1-year mortality after MI or IS was significantly higher in the highest quartile of GGT compared to the lowest quartile (HR, 1.46; 95% CI, 1.40-1.52). The implication of GGT on MI, IS, and mortality persisted regardless of traditional cardiovascular risk parameters. This study demonstrated the unique pattern of association of ALT, AST, and GGT with the development of CVD and all-cause mortality in the Korean population. In particular, GGT showed the most robust linear relationship with mortality before and after cardiovascular events independent of risk factors.

Increased levels of low-density lipoprotein cholesterol within the normal range as a risk factor for nonalcoholic fatty liver disease

Objectives

Dyslipidemia exists within the setting of NAFLD and the relationship of a normal level of low-density lipoprotein cholesterol (LDL-c) with NAFLD is largely unknown. This large population-based study aimed to investigate the association between LDL-c levels within the normal range and the incidence of NAFLD.

Methods

A total of 60527 subjects from 2 medical centers who had undergone liver ultrasonography were initially enrolled into this study. NAFLD was defined by ultrasonographic detection of steatosis in the absence of other liver disease. Subjects were divided into 4 groups (Q1 to Q4) by normal LDL-c quartiles : Q1: ≤ 2.00, Q2: 2.10-2.35, Q3: 2.36-2.68 and Q4: 2.69-3.12 mmol/L. The odds ratios (OR), hazard ratio (HR) and 95% confidence intervals (CIs) for NAFLD were calculated across each quartile of LDL-c, using the Q1 as reference.

Results

The prevalence rates of NAFLD in a cross-sectional population from Q1 to Q4 were 19.34%, 25.86%, 35.65% and 42.08%, respectively. The OR for NAFLD in the cross-sectional population were 1.31 (95% CI 1.14-1.54), 1.73 (95% CI 1.46-2.04), and 1.82 (95% CI 1.49-2.23), respectively, after adjusting for known confounding variables. The HR for NAFLD in the longitudinal population were 1.23 (95% CI 1.12-1.35), 1.57 (95% CI 1.44-1.72) and 2.02 (95% CI 1.86-2.21), compared with Q1. Subjects with higher LDL-c level within the normal range had an increased cumulative incidence rate of NAFLD.

Conclusions

Increased levels of LDL-c within the normal range may play a significant role in the prevalence and incidence of NAFLD, independent of other confounding factors.

Non-alcoholic fatty liver disease and cardiovascular risk: Pathophysiological mechanisms and implications

Non-alcoholic fatty liver disease (NAFLD) has become one of the most frequent chronic liver diseases in the Western society and its prevalence is likely to rise even further. An increasing body of evidence shows that NAFLD is not only a potentially progressive liver disease, but also has systemic consequences. More specifically, evidence points out that NAFLD has to be considered as a significant independent risk factor for subclinical and clinical cardiovascular disease (CVD). Long-term follow-up studies demonstrate cardiovascular mortality to be the most important cause of death in NAFLD patients. Moreover, ample evidence associates NAFLD with endothelial dysfunction, increased pulse wave velocity, increased coronary arterial calcifications and increased carotid intima media thickness, all established markers for CVD. Despite of all this evidence, the mechanisms by which NAFLD causally contributes to CVD are not fully elucidated. Furthermore, an extensive overview of all potential pathophysiological mechanisms and the corresponding current data are lacking. In this review we summarise current knowledge, originating from fundamental and clinical research, that mechanistically links NAFLD to CVD. Subsequently, the impact of CVD on current clinical practice and future research in the area of NALFD are discussed.

Non-alcoholic fatty liver disease and dyslipidemia: An update

Non-alcoholic fatty liver (NAFLD) is the most common liver disease worldwide, progressing from simple steatosis to necroinflammation and fibrosis (leading to non-alcoholic steatohepatitis, NASH), and in some cases to cirrhosis and hepatocellular carcinoma. Inflammation, oxidative stress and insulin resistance are involved in NAFLD development and progression. NAFLD has been associated with several cardiovascular (CV) risk factors including obesity, dyslipidemia, hyperglycemia, hypertension and smoking. NAFLD is also characterized by atherogenic dyslipidemia, postprandial lipemia and high-density lipoprotein (HDL) dysfunction. Most importantly, NAFLD patients have an increased risk for both liver and CV disease (CVD) morbidity and mortality. In this narrative review, the associations between NAFLD, dyslipidemia and vascular disease in NAFLD patients are discussed. NAFLD treatment is also reviewed with a focus on lipid-lowering drugs. Finally, future perspectives in terms of both NAFLD diagnostic biomarkers and therapeutic targets are considered.

Nonalcoholic fatty liver disease severity is associated with the ratios of total cholesterol and triglycerides to high-density lipoprotein cholesterol

BACKGROUND

Limited data support the notion that lipid ratios are risk factors for nonalcoholic fatty liver disease (NAFLD). We evaluated the association between lipid ratios and NAFLD.

METHODS

This was a large population, cross-sectional, retrospective study. Data on NAFLD severity, blood pressure, fasting glucose, total cholesterol (TC), triglyceride (TG), and high-density lipoprotein cholesterol (HDL-C) levels were obtained from 44,767 examinees at single health checkup center. The enrollees were stratified into four subgroups based on their TC/HDL-C and TG/HDL-C ratios. We used multivariate analyses to evaluate the odds between lipid ratios and NAFLD.

RESULTS

The prevalence rate of fatty liver in this study was 53.76%. In the baseline subgroup with the lowest TC/HDL-C and TG/HDL-C ratios, the prevalence of NAFLD, hypertension, and diabetes was lower than that of the other three subgroups. Patients with higher lipid ratios had a significantly greater risk for advanced NAFLD.

CONCLUSIONS

Adults with high TC/HDL-C or TG/HDL-C ratios, or both, have a greater risk for NAFLD, especially advanced NAFLD.