Relation of nonalcoholic fatty liver disease and Framingham Risk Score to flow-mediated dilation in patients with cardiometabolic risk factors

Rising Influence of Nanotechnology in Addressing Oxidative Stress-Related Liver Disorders

Reactive oxygen species (ROS) play a significant role in the survival and decline of various biological systems. In liver-related metabolic disorders such as steatohepatitis, ROS can act as both a cause and a consequence. Alcoholic steatohepatitis (ASH) and non-alcoholic steatohepatitis (NASH) are two distinct types of steatohepatitis. Recently, there has been growing interest in using medications that target ROS formation and reduce ROS levels as a therapeutic approach for oxidative stress-related liver disorders. Mammalian systems have developed various antioxidant defenses to protect against excessive ROS generation. These defenses modulate ROS through a series of reactions, limiting their potential impact. However, as the condition worsens, exogenous antioxidants become necessary to control ROS levels. Nanotechnology has emerged as a promising avenue, utilizing nanocomplex systems as efficient nano-antioxidants. These systems demonstrate enhanced delivery of antioxidants to the target site, minimizing leakage and improving targeting accuracy. Therefore, it is essential to explore the evolving field of nanotechnology as an effective means to lower ROS levels and establish efficient therapeutic interventions for oxidative stress-related liver disorders.

Rising Influence of Nanotechnology in Addressing Oxidative Stress-Related Liver Disorders

Reactive oxygen species (ROS) play a significant role in the survival and decline of various biological systems. In liver-related metabolic disorders such as steatohepatitis, ROS can act as both a cause and a consequence. Alcoholic steatohepatitis (ASH) and non-alcoholic steatohepatitis (NASH) are two distinct types of steatohepatitis. Recently, there has been growing interest in using medications that target ROS formation and reduce ROS levels as a therapeutic approach for oxidative stress-related liver disorders. Mammalian systems have developed various antioxidant defenses to protect against excessive ROS generation. These defenses modulate ROS through a series of reactions, limiting their potential impact. However, as the condition worsens, exogenous antioxidants become necessary to control ROS levels. Nanotechnology has emerged as a promising avenue, utilizing nanocomplex systems as efficient nano-antioxidants. These systems demonstrate enhanced delivery of antioxidants to the target site, minimizing leakage and improving targeting accuracy. Therefore, it is essential to explore the evolving field of nanotechnology as an effective means to lower ROS levels and establish efficient therapeutic interventions for oxidative stress-related liver disorders.

Challenges in Improving Adherence to Diet and Drug Treatment in Hypercholesterolemia Patients

Poor adherence to chronic disease treatment may seriously compromise the effectiveness of therapy, characterizing itself as a critical element for the population's health, both from the point of view of quality of life and health economics. The causes of low adherence are many and can depend on the patient, the physician and the healthcare system. Low adherence to dietary recommendations and lipid-lowering drug therapy for hypercholesterolemia is a widespread phenomenon that may strongly limit the great advantages of serum lipid reduction strategies in primary and secondary cardiovascular prevention. Many patients discontinue treatment, and adherence decreases with time. Increasing therapeutic adherence can have a much greater impact on the health of the population than any other therapeutic advance. There are numerous strategies to increase therapy adherence according to behavior change theories. They concern the doctor and the patient. Some must be implemented at the time of prescription, others later during the follow-up. The active role of the patient in the therapeutic decision and the shared definition of LDL cholesterol targets are of paramount importance. The aim of this narrative review is to summarize evidence on current levels of adherence to lipid-lowering strategies, the causes of the lack of adequate adherence and possible physician-applicable strategies to improve it.

Endothelial Dysfunction in Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis

Individuals with nonalcoholic fatty liver disease (NAFLD) are characterized by increased cardiovascular risk. Endothelial dysfunction, a mechanism implicated in those processes, may constitute the missing link in this interaction. Therefore, this systematic review and meta-analysis aims to evaluate the association of endothelial dysfunction, assessed by flow-mediated dilation (FMD) of the brachial artery, with NAFLD. We conducted a systematic literature search for studies assessing the difference in FMD between patients with NAFLD and controls. Exclusion criteria consisted of preclinical studies, studies in children/adolescents, no FMD assessment, and the absence of an NAFLD/control group. The database search identified 96 studies. Following the application of the exclusion criteria, 22 studies were included in the meta-analysis (NAFLD: 2164 subjects; control: 3322 subjects). Compared with controls, patients with NAFLD had significantly lower FMD% values (SMD: −1.37, 95% CI −1.91 to −0.83, p < 0.001, I2: 98%). Results remained unaffected after exclusion of any single study. Subgroup analysis revealed significantly decreased FMD in NAFLD subjects diagnosed with liver ultrasound or liver biopsy compared with method combination or other methods, while no differences were observed according to the chosen cuff inflation threshold, the presence of a significant difference in obesity measures between the groups, or the type of the control group (age- and sex-matched vs. other). Funnel plot asymmetry was not observed. Finally, compared with patients with pure steatosis, individuals with nonalcoholic steatohepatitis had significantly lower FMD (SMD: −0.81, 95% CI −1.51 to −0.31, p = 0.003, I2: 81%). In conclusion, FMD of the brachial artery, indicative of endothelial dysfunction, was significantly reduced in subjects with nonalcoholic fatty liver disease. Patients with nonalcoholic steatohepatitis might be facing a more pronounced endothelial impairment.

Atherosclerosis and Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a common disease defined by excess fat deposition in the liver. The course of NAFLD is not fully understood, however, some pathogenic mechanisms have been identified. Accumulation of fat in liver cells is associated with insulin resistance, central obesity, triglyceride accumulation in the liver and hepatic fatty acid metabolism dysregulation that cause steatosis. The other process leads to hepatocyte inflammation and necrosis, which leads to severe hepatic disease; non-alcoholic steatohepatitis. Many clinical studies have underlined the link between NAFLD and atherosclerosis. NAFLD may alter the balance lipid-glucose metabolism as well as increase the risk of hypertension and systemic inflammation. This results in a greater risk of vascular events. The present review considers the link between NAFLD and atherosclerosis.

High Compliance to Mediterranean Diet Associates with Lower Platelet Activation and Liver Collagen Deposition in Patients with Nonalcoholic Fatty Liver Disease

The Mediterranean diet (Med-Diet) is considered the most effective dietary patterns to obtain weight loss in NAFLD patients. Previous evidence suggested that Med-Diet adherence could reduce cardiovascular risk and have a beneficial effect on NAFLD severity. Aim of the study was to investigate the relationship between Med-Diet adherence, platelet activation (PA), and liver collagen deposition. The study was performed in 655 consecutive NAFLD outpatients from the PLINIO study, a prospective observational cohort study aimed to identify non-conventional predictors of liver fibrosis progression in NAFLD. PA was measured by the serum thromboxane B2 (TxB2), and liver collagen deposition by N-terminal propeptide of type III collagen (Pro-C3). Adherence to the Med-diet was investigated by a short nine-item validated dietary questionnaire. Patients with high Med-Diet adherence were older and had less metabolic syndrome and lower serum triglycerides, GGT, TxB2, and Pro-C3. At multivariate regression analyses, in the linear model, the Med-Diet score negatively correlated with both TxB2 (Beta = −0.106; p = 0.009) and Pro-C3 (Beta = −0.121; p = 0.002) and in the logistic model high adherence inversely correlated with higher TxB2 tertiles (II tertile: OR = 0.576, p = 0.044; III tertile: OR = 0.556, p = 0.026) and Pro-C3 tertile (III tertile: OR = 0.488, p = 0.013). Low consumption of red meat inversely correlated with higher TxB2 tertile (II tertile: OR = 0.448, p < 0.001, III tertile: OR = 0.567, p = 0.004). In conclusion, NAFLD patients with high adherence to the Med-Diet show lower PA and liver collagen deposition, suggesting a protective role of the Med-Diet against NAFLD progression and cardiovascular risk. In addition, the correlation between TxB2 and Pro-C3 suggests a link between NAFLD severity and cardiovascular risk.

Oxidative Stress in Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a challenging disease caused by multiple factors, which may partly explain why it still remains an orphan of adequate therapies. This review highlights the interaction between oxidative stress (OS) and disturbed lipid metabolism. Several reactive oxygen species generators, including those produced in the gastrointestinal tract, contribute to the lipotoxic hepatic (and extrahepatic) damage by fatty acids and a great variety of their biologically active metabolites in a “multiple parallel-hit model”. This leads to inflammation and fibrogenesis and contributes to NAFLD progression. The alterations of the oxidant/antioxidant balance affect also metabolism-related organelles, leading to lipid peroxidation, mitochondrial dysfunction, and endoplasmic reticulum stress. This OS-induced damage is at least partially counteracted by the physiological antioxidant response. Therefore, modulation of this defense system emerges as an interesting target to prevent NAFLD development and progression. For instance, probiotics, prebiotics, diet, and fecal microbiota transplantation represent new therapeutic approaches targeting the gut microbiota dysbiosis. The OS and its counter-regulation are under the influence of individual genetic and epigenetic factors as well. In the near future, precision medicine taking into consideration genetic or environmental epigenetic risk factors, coupled with new OS biomarkers, will likely assist in noninvasive diagnosis and monitoring of NAFLD progression and in further personalizing treatments.

National digestive disease specialists survey on cardiovascular risk management in non-alcoholic fatty liver disease in spanish hospitals

BACKGROUND & AIMS

Cardiovascular disease (CVD) is the main cause of mortality among non-alcoholic fatty liver disease (NAFLD) patients. The aim was to explore the level of knowledge and clinical management of cardiovascular risk (CVR) in NAFLD patients by Digestive Disease specialists.

METHODS

An anonymous web-based survey was designed with 44 close-ended questions, divided into five sections, that were based on current guidelines on CVD prevention. Between November 2019 and January 2020, Digestive Disease specialists from Spanish hospitals were invited to participate in this survey via email and Twitter. Student's t, chi-square and Fishers' exact tests, and logistic regression were used for data analysis.

RESULTS

208 clinicians completed the survey. Most respondents (83.2%) believe that NAFLD is an independent risk factor for CVD, especially in the presence of NASH and fibrosis. Personal history of CVDs and cardiovascular risk-related comorbidities are collected by more than 75% of respondents. However, less than 17% perform an elementary physical examination to address the CVR, except weight which is evaluated by 69.8%. Over 54% of respondents do not perform or request any supplementary tests for CVR assessment, and only 10.2% use specific calculators. Furthermore, 54.3% spend less than 5 minutes giving lifestyle advice, and more than 52% do not start drug treatment after a recent diagnosis of any cardiovascular comorbidity. Only 25.6% have a multidisciplinary Unit for metabolic comorbidities in their hospitals, although 89% of the respondents would support the implementation of this Unit.

CONCLUSIONS

Cardiovascular risk management in daily clinical practice by Digestive Disease specialists in Spain remains suboptimal.

New Insights into the Pathogenesis of Non-Alcoholic Fatty Liver Disease: Gut-Derived Lipopolysaccharides and Oxidative Stress

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide. The intricate NAFLD pathogenesis is summarized by the multiple-hits hypothesis, which combines all the environmental and genetic factors that promote the development of NAFLD into a single scenario. Among these, bacterial lipopolysaccharides (LPS) are derived from the overgrowth of Gram-negative bacteria and translocated mainly as a consequence of enhanced intestinal permeability. Furthermore, oxidative stress is increased in NAFLD as a consequence of reactive oxygen species (ROS) overproduction and a shortage of endogenous antioxidant molecules, and it is promoted by the interaction between LPS and the Toll-like receptor 4 system. Interestingly, oxidative stress, which has previously been described as being overexpressed in cardiovascular disease, could represent the link between LPS and the increased cardiovascular risk in NAFLD subjects. To date, the only effective strategy for the treatment of NAFLD and non-alcoholic steatohepatitis (NASH) is the loss of at least 5% body weight in overweight and/or obese subjects. However, the dose-dependent effects of multispecies probiotic supplementation on the serum LPS level and cardiometabolic profile in obese postmenopausal women were demonstrated. In addition, many antibiotics have regulatory effects on intestinal microbiota and were able to reduce serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and tumor necrosis factor alpha (TNF-α) in NASH animal models. Regarding the oxidant status, a Mediterranean diet has been reported to reduce oxidant stress, while vitamin E at high daily dosages induced the resolution of NASH in 36% of treated patients. Silymarin had the positive effect of reducing transaminase levels in NAFLD patients and long-term treatment may also decrease fibrosis and slow liver disease progression in NASH. Finally, the influence of nutraceuticals on gut microbiota and oxidant stress in NAFLD patients has not yet been well elucidated and there are insufficient data either to support or refuse their use in these subjects.

Clinical considerations in the management of non-alcoholic steatohepatitis cirrhosis pre- and post-transplant: A multi-system challenge

Non-alcoholic steatohepatitis (NASH) is the most common chronic liver disease worldwide, and the fastest growing indication for liver transplantation in the United States. NASH is now the leading etiology for liver transplantation in women, the second leading indication for men, and the most common cause amongst recipients aged 65 years and older. Patients with end-stage liver disease related to NASH represent a unique and challenging patient population due the high incidence of associated comorbid diseases, including obesity, type 2 diabetes (T2D), and hypertension. These challenges manifest in the pre-liver transplantation period with increased waitlist times and waitlist mortality. Furthermore, these patients carry considerable risk of morbidity and mortality both before after liver transplantation, with high rates of T2D, cardiovascular disease, chronic kidney disease, poor nutrition, and disease recurrence. Successful transplantation for these patients requires identification and management of their comorbidities in the face of liver failure. Multidisciplinary evaluations include a thorough pre-transplant workup with a complete cardiac evaluation, control of diabetes, nutritional support, and even, potentially, consultation with a bariatric surgeon. This article provides a comprehensive review of the conditions and challenges facing patients with NASH cirrhosis undergoing liver transplantation and provides recommendations for evaluation and management to optimize them before liver transplantation to produce successful outcomes.

Association between non-alcoholic fatty liver disease and obstructive sleep apnea

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is an emerging liver disease and currently the most common cause of incidental abnormal liver tests. The pathogenesis of NAFLD is multifactorial and many mechanisms that cause fatty liver infiltration, inflammation, oxidative stress and progressive fibrosis have been proposed. Obstructive sleep apnea (OSA) may be linked with the pathogenesis and the severity of NAFLD.

AIM

To study the association between NAFLD and OSA considering also the efficacy of continuous positive airway pressure (CPAP) treatment.

METHODS

A PubMed search was conducted using the terms “non-alcoholic fatty liver disease AND (obstructive sleep apnea OR obstructive sleep disorders OR sleep apnea)”. Research was limited to title/abstract of articles published in English in the last 5 years; animal and child studies, case reports, commentaries, letters, editorials and meeting abstracts were not considered. Data were extracted on a standardized data collection table which included: First author, publication year, country, study design, number of patients involved, diagnosis and severity of OSA, diagnosis of NAFLD, patient characteristics, results of the study.

RESULTS

In total, 132 articles were initially retrieved on PubMed search and 77 in the last five years. After removal of irrelevant studies, 13 articles were included in the qualitative analysis. There was a total of 2753 participants across all the studies with a mean age between 42 and 58 years. The proportion of males ranged from 21% to 87.9% and the mean body mass index ranged from 24.0 to 49.9 kg/m². The results of this review showed an increased prevalence of NAFLD in patients with diagnosis of OSA, even in the absence of coexisting comorbidities such as obesity or metabolic syndrome. Furthermore, the severity of NAFLD is associated with the increase in OSA severity. Effective CPAP treatment, although not always decisive, may stabilize or slow NAFLD progression with benefits on metabolic and cardiovascular functions.

CONCLUSION

In NAFLD patients, although asymptomatic, it is recommended to systematically perform polysomnography in order to early and better treat them before the development of potentially life threatening systemic dysfunctions.

Reduced lysosomal acid lipase activity: A new marker of liver disease severity across the clinical continuum of non-alcoholic fatty liver disease?

Lysosomal acid lipase (LAL) plays a key role in intracellular lipid metabolism. Reduced LAL activity promotes increased multi-organ lysosomal cholesterol ester storage, as observed in two recessive autosomal genetic diseases, Wolman disease and Cholesterol ester storage disease. Severe liver steatosis and accelerated liver fibrosis are common features in patients with genetic LAL deficiency. By contrast, few reliable data are available on the modulation of LAL activity in vivo and on the epigenetic and metabolic factors capable of regulating its activity in subjects without homozygous mutations of the Lipase A gene. In the last few years, a less severe and non-genetic reduction of LAL activity was reported in children and adults with non-alcoholic fatty liver disease (NAFLD), suggesting a possible role of LAL reduction in the pathogenesis and progression of the disease. Patients with NAFLD show a significant, progressive reduction of LAL activity from simple steatosis to non-alcoholic steatohepatitis and cryptogenic cirrhosis. Among cirrhosis of different etiologies, those with cryptogenic cirrhosis show the most significant reductions of LAL activity. These findings suggest that the modulation of LAL activity may become a possible new therapeutic target for patients with more advanced forms of NAFLD. Moreover, the measurement of LAL activity may represent a possible new marker of disease severity in this clinical setting.

Mortality Risk Detected by Atherosclerotic Cardiovascular Disease Score in Patients With Nonalcoholic Fatty Liver Disease

Cardiovascular diseases (CVDs) are the leading cause of mortality in patients with nonalcoholic fatty liver disease (NAFLD). Our aim was to assess the association of atherosclerotic cardiovascular disease (ASCVD) risk scores with overall and cardiac-specific mortality among patients with NAFLD. We used the National Health and Nutrition Examination Survey III with the National Death Index-linked mortality files. NAFLD was defined by ultrasound as presence of steatosis in the absence of secondary causes of liver disease. High risk for CVD was defined as a 10-year ASCVD score ≥7.5%. Hazard ratios (HRs) and population-attributable fractions (PAFs) of high risk for CVD were calculated. Among 1,262 subjects with NAFLD (47.9% men; 41.2% white; mean age, 56.3 years), the prevalence of high risk for CVD was 55.9% and 4.8% had advanced fibrosis. After a median follow-up of 17.7 years, 482 subjects (38.2%) died of overall causes, of whom 382 (79.3%) had a high risk for CVD. The unadjusted overall and cardiac-specific mortality were higher for patients with NAFLD who had a high risk for CVD compared to subjects with NAFLD with a low risk for CVD (57.3% vs. 16.8% for overall mortality; 16.4% vs. 3.5% for cardiovascular mortality). After controlling for risk factors associated with mortality, high risk for CVD was associated with a 42% higher overall mortality rate (adjusted HR [aHR], 1.42; 95% confidence interval [CI], 1.05-1.91) and twice the risk of cardiovascular mortality (aHR, 2.02; 95% CI, 1.12-3.65). Adjusted PAFs were 11.4% for overall mortality and 44.9% for cardiovascular mortality. Conclusion: Among patients with NAFLD, ASCVD score ≥7.5% was associated with a higher risk of overall and cardiac-specific mortality.

Remnant Lipoprotein Cholesterol and Cardiovascular and Cerebrovascular Events in Patients with Non-Alcoholic Fatty Liver Disease

: Non-alcoholic fatty liver disease (NAFLD) is characterized by an atherogenic dyslipidaemia and an increased cardiovascular risk. Remnant lipoprotein cholesterol (RLP-C) is emerging as a novel cardiovascular risk factor, but its predictive value in patients with NAFLD is unknown. We investigated factors affecting RLP-C levels, and the association with major adverse cardiovascular and cerebrovascular events (MACCE) in NAFLD. A prospective observational cohort study was carried out including 798 unselected patients with cardio-metabolic diseases screened by ultrasound for the presence of NAFLD. Fasting RLP-C (mg/dL) was calculated as total cholesterol-(HDL (high-density lipoprotein) + LDL (low-density-lipoprotein)). Primary endpoint of the follow-up study was a combined endpoint of MACCE. Patients with NAFLD (79.2%) had higher median fasting RLP-C in comparison to those without (27.0 vs. 20.0 mg/ dL, respectively p < 0.001). Metabolic syndrome, NAFLD, age above median, and female sex were independently associated to fasting RLP-C above the median. In patients with NAFLD, values of RLP-C were associated with liver disease severity, as shown by the increasing value of RLP-C across tertiles of aspartate aminotransferase (AST) (p = 0.002) and gamma-glutamyl transpeptidase (GGT) (p < 0.001). Furthermore, levels of RLP-C and Hamaguchi score, were significantly correlated (r = 0.193, p < 0.001). During a median follow-up of 32 months (interquartile range: 14.2⁻51.7, 1700 person-years), 41 MACCE (2.41%/year) were registered in 596 NAFLD patients. The rate of events was higher in NAFLD patients with RLP-C above the median compared to those below (log-rank test p = 0.040). Age (hazard ratio (HR) 1.039, 95% confidence interval (CI), 1.005⁻1.074, p = 0.024), previous cardiovascular events (HR 2.210, 95% CI, 1.052⁻4.643, p = 0.036), female sex (HR 0.454, 95% CI, 0.208⁻0.989, p = 0.047) and RLP-C above the median (HR 2.202, 95% CI, 1.132⁻4.285, p = 0.020) were associated with MACCE. In conclusion, we found that NAFLD was independently associated with higher circulating RLP-C, and that high RLP-C levels were predictive of MACCE in patients with NAFLD.

"Non alcoholic fatty liver disease and eNOS dysfunction in humans"

Background

NAFLD is associated to Insulin Resistance (IR). IR is responsible for Endothelial Dysfunction (ED) through the impairment of eNOS function. Although eNOS derangement has been demonstrated in experimental models, no studies have directly shown that eNOS dysfunction is associated with NAFLD in humans. The aim of this study is to investigate eNOS function in NAFLD patients.

Methods

Fifty-four NAFLD patients were consecutively enrolled. All patients underwent clinical and laboratory evaluation and liver biopsy. Patients were divided into two groups by the presence of NAFL or NASH. We measured vascular reactivity induced by patients’ platelets on isolated mice aorta rings. Immunoblot assays for platelet-derived phosphorylated-eNOS (p-eNOS) and immunohistochemistry for hepatic p-eNOS have been performed to evaluate eNOS function in platelets and liver specimens. Flow-mediated-dilation (FMD) was also performed. Data were compared with healthy controls.

Results

Twenty-one (38, 8%) patients had NAFL and 33 (61, 7%) NASH. No differences were found between groups and controls except for HOMA and insulin (p < 0.0001). Vascular reactivity demonstrated a reduced function induced from NAFLD platelets as compared with controls (p < 0.001), associated with an impaired p-eNOS in both platelets and liver (p < 0.001). NAFL showed a higher impairment of eNOS phosphorylation in comparison to NASH (p < 0.01). In contrast with what observed in vitro, the vascular response by FMD was worse in NASH as compared with NAFL.

Conclusions

Our data showed, for the first time in humans, that NAFLD patients show a marked eNOS dysfunction, which may contribute to a higher CV risk. eNOS dysfunction observed in platelets and liver tissue didn’t match with FMD.

Associations of central aortic pressure and brachial blood pressure with flow mediated dilatation in apparently healthy Japanese men: The Circulatory Risk in Communities Study (CIRCS)

BACKGROUND AND AIMS

Endothelial dysfunction is considered the first stage in the development of atherosclerosis and cardiovascular disease, and brachial flow-mediated dilation (FMD) is a measure of endothelial function. It is uncertain which of central systolic aortic pressure (CAP) or brachial systolic blood pressure (SBP) is more strongly associated with FMD. Therefore, we examined the correlations of CAP and SBP with FMD in Japanese men.

METHODS

The study subjects comprised 507 male volunteers aged 30-79 years that were residents in two communities under the Circulatory Risk in Communities Study (CIRCS) between 2013 and 2015. The low percent change of FMD (%FMD) ≤5.0%, after 5 min of reactive hyperemia evaluated by the brachial artery diameter, was used to assess endothelial dysfunction. Values of CAP and SBP were divided into tertiles, with the lowest tertile used as a reference.

RESULTS

After adjustment for cardiovascular risk factors, the multivariable odds ratio (95% CI) of low FMD for the highest versus lowest tertile of CAP was 1.5 (0.9-2.6) for total subjects and 1.4 (0.5-3.8) for those with, and 2.4 (1.2-4.8) for those without antihypertensive medication use. The corresponding odd ratios for the highest versus lowest tertile of SBP were 0.9 (0.5-1.5), 0.8 (0.3-2.2), and 1.3 (0.7-2.5), respectively.

CONCLUSIONS

Higher CAP levels were associated with low FMD for men without antihypertensive medication, but such an association was not found for SBP levels.

Under-prescription of statins in patients with non-alcoholic fatty liver disease

BACKGROUND AND AIM

Non-alcoholic fatty liver disease (NAFLD) is a common disease associated with high cardiovascular risk. Management of dyslipidaemia plays a pivotal role in the prevention of CV events and statins have proved to be safe in these patients. However, in everyday clinical practice statin prescription is sometimes limited because of the concern of physicians about side-effects. The aim of the study was to investigate if the presence of NAFLD affects the prescription of lipid-lowering treatment in a large series of patients with cardio-metabolic disorders.

METHODS AND RESULTS

Cardiovascular risk and LDL-C targets were defined according to ESC/EAS Guidelines in 605 consecutive adult subjects referred for screening of suspected metabolic diseases. Liver steatosis was assessed by ultrasound Hamaguchi criteria. In the whole cohort, 442 patients had indication for cholesterol-lowering treatment. Lack of statin prescription was present in 230 (52.0%) patients. Of these, 77 (33.5%) were very high-risk, 48 (20.8%) high-risk, and 105 (45.6%) moderate risk patients. Only 44% of the NAFLD patients with indication for statin treatment were on therapy. NAFLD patients on statin treatment had significantly lower ALT values as compared to those not on treatment (p < 0.05).

CONCLUSIONS

Our findings show that about 50% of patients with indication to statin treatment do not receive any cholesterol-lowering medication. Statin under-use was particularly high in subjects with NAFLD. Use of statin treatment should be encouraged in the context of NAFLD, as it may improve lipid profile and reduce the cardiovascular risk in this setting.

Nonalcoholic fatty liver disease as a multi-systemic disease

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease. NAFLD includes a wide spectrum of liver conditions ranging from simple steatosis to nonalcoholic steatohepatitis and advanced hepatic fibrosis. NAFLD has been recognized as a hepatic manifestation of metabolic syndrome linked with insulin resistance. NAFLD should be considered not only a liver specific disease but also an early mediator of systemic diseases. Therefore, NAFLD is usually associated with cardiovascular disease, chronic kidney disease, type 2 diabetes, obesity, and dyslipidemia. NAFLD is highly prevalent in the general population and is associated with increased cardiovascular morbidity and mortality. The underlying mechanisms and pathogenesis of NAFLD with regard to other medical disorders are not yet fully understood. This review focuses on pathogenesis of NAFLD and its relation with other systemic diseases.

Long-term clinical outcomes after fatty liver screening in patients undergoing coronary angiogram: A prospective cohort study

There is ongoing debate on whether screening for nonalcoholic fatty liver disease (NAFLD) is worthwhile in high-risk groups. Because of shared risk factors, NAFLD is highly prevalent in patients with coronary artery disease. We aimed to test the hypothesis that NAFLD screening in patients requiring coronary angiogram would identify high-risk patients and predict long-term clinical outcomes. This was a prospective cohort study. NAFLD screening was performed by abdominal ultrasonography before coronary angiogram in 612 consecutive patients. At baseline, 356 (58.2%) patients had NAFLD. NAFLD patients, compared with those without, were more likely to have >50% stenosis in one or more coronary arteries (84.6% vs. 64.1%; P < 0.001) and therefore require percutaneous coronary intervention (68.3% vs. 43.4%; P < 0.001). During 3,679 patient-years of follow-up, 47 (13.2%) NAFLD patients and 59 (23.0%) patients without NAFLD died (age- and sex-adjusted hazard ratio [aHR]: 0.36; 95% confidence interval [CI]: 0.18-0.70; P = 0.003). Composite cardiovascular outcomes (cardiovascular deaths, nonfatal myocardial infarction, heart failure, or secondary interventions) were similar between groups (36.5% vs. 37.1%; aHR, 0.90; 95% CI: 0.69-1.18). Older age and diabetes were the only independent factors associated with cardiovascular events. Only 2 patients, both in the NAFLD group, died of primary liver cancer. No other patients developed liver-related complications.

CONCLUSION

In patients with clinical indications for coronary angiogram, the presence of NAFLD is associated with coronary artery stenosis and need for coronary intervention, but not increased mortality or cardiovascular complications. Liver cancer and cirrhotic complications are rare. Our data do not support NAFLD screening in this patient group at present, but studies with a longer duration of follow-up are needed.

Research advances in the relationship between nonalcoholic fatty liver disease and atherosclerosis

Nonalcoholic fatty liver disease (NAFLD) is a metabolic stress-induced liver disease that is closely related not only to genetic susceptibility but also to insulin resistance and highly linked with metabolic syndrome. In recent years, the prevalence of NAFLD has increased rapidly, paralleling the epidemic of type 2 diabetes mellitus and obesity leading to cardiovascular disease. It has been demonstrated that NAFLD is highly associated with atherosclerosis. With recently gained knowledge, it appears that NAFLD may induce insulin resistance, dyslipidemia, oxidative stress, inflammation, and fluctuation of adipokines associated with atherosclerosis. In this review, we aimed to summarize recent discoveries related to both NAFLD and atherosclerosis, and to identify possible mechanisms linking them.

Does Lysosomial Acid Lipase Reduction Play a Role in Adult Non-Alcoholic Fatty Liver Disease?

Lysosomal Acid Lipase (LAL) is a key enzyme involved in lipid metabolism, responsible for hydrolysing the cholesteryl esters and triglycerides. Wolman Disease represents the early onset phenotype of LAL deficiency rapidly leading to death. Cholesterol Ester Storage Disease is a late onset phenotype that occurs with fatty liver, elevated aminotransferase levels, hepatomegaly and dyslipidaemia, the latter characterized by elevated LDL-C and low HDL-C. The natural history and the clinical manifestations of the LAL deficiency in adults are not well defined, and the diagnosis is often incidental. LAL deficiency has been suggested as an under-recognized cause of dyslipidaemia and fatty liver. Therefore, LAL activity may be reduced also in non-obese patients presenting non-alcoholic fatty liver disease (NAFLD), unexplained persistently elevated liver transaminases or with elevation in LDL cholesterol. In these patients, it could be indicated to test LAL activity. So far, very few studies have been performed to assess LAL activity in representative samples of normal subjects or patients with NAFLD. Moreover, no large study has been carried out in adult subjects with NAFLD or cryptogenic cirrhosis.

Similar Reduction of Cholesterol-Adjusted Vitamin E Serum Levels in Simple Steatosis and Non-Alcoholic Steatohepatitis

Objectives:

Reduced vitamin E levels have been reported in patients with non-alcoholic steatohepatitis (NASH), but no conclusive data on patients with simple steatosis (SS) are available. Aim of this study was to investigate the association between serum vitamin E levels and SS.

Methods:

A cohort of 312 patients with cardio-metabolic risk factors was screened for liver steatosis by ultrasonography (US). We reasonably classified as SS patients with US-fatty liver, normal liver function tests (LFTs) and with Cytokeratin 18 <246 mIU/ml. Liver biopsy was performed in 41 patients with US-fatty liver and persistent elevation of LFTs (>6 months). Serum cholesterol-adjusted vitamin E (Vit E/chol) levels were measured.

Results:

Mean age was 53.9±12.5 years and 38.4% were women. Non-alcoholic fatty liver disease (NAFLD) was detected at US in 244 patients; of those 39 had biopsy-proven NASH and 2 borderline NASH. Vit E/chol was reduced in both SS (3.4±2.0, P<0.001), and NASH (3.5±2.1, P=0.006) compared with non-NAFLD patients (4.8±2.0 μmol/mmol chol). No difference was found between SS and NASH (P=0.785). After excluding patients with NASH, a multivariable logistic regression analysis found that Vit E/chol (odds ratio (OR): 0.716, 95% confidence interval (CI) 0.602–0.851, P<0.001), alanine aminotransferase (ALT, OR: 1.093, 95% CI 1.029–1.161, P=0.004), body mass index (OR: 1.162, 95% CI 1.055–1.279, P=0.002) and metabolic syndrome (OR: 5.725, 95% CI 2.247–14.591, P<0.001) were factors independently associated with the presence of SS.

Conclusions:

Reduced vitamin E serum levels are associated with SS, with a similar reduction between patients with SS and NASH, compared with non-NAFLD patients. Our findings suggest that the potential benefit of vitamin E supplementation should be investigated also in patients with SS.

Reduced Lysosomal Acid Lipase Activity in Adult Patients With Non-alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is characterized by intra-hepatic fat accumulation and mechanisms involved in its pathogenesis are not fully explained. Lysosomal Acid Lipase (LAL) is a key enzyme in lipid metabolism. We investigated its activity in patients with fatty liver.

LAL activity (nmol/spot/h) was measured in 100 adult healthy subjects (HS) and in 240 NAFLD patients. A sub-analysis on 35 patients with biopsy-proven non-alcoholic steatohepatitis (NASH) was performed.

Median LAL activity was 1.15 (0.95–1.72) in HS. It was significantly reduced in NAFLD [0.78 (0.61–1.01), p < 0.001 vs. HS]. A further reduction was observed in the subgroup of NASH [0.67 (0.51–0.77), p < 0.001 vs. HS]. Patients with LAL activity below median had higher values of serum total cholesterol (p < 0.05) and LDL-c (p < 0.05), and increased serum liver enzymes (ALT, p < 0.001; AST, p < 0.01; GGT, p < 0.01). At multivariable logistic regression analysis, factors associated with LAL activity below median were ALT (OR: 1.018, 95% CI 1.004–1.032, p = 0.011) and metabolic syndrome (OR: 2.551, 95% CI 1.241–5.245, p = 0.011), whilst statin use predicted a better LAL function (OR: 0.464, 95% CI 0.248–0.866, p = 0.016).

Our findings suggest a strong association between impaired LAL activity and NAFLD. A better knowledge of the role of LAL may provide new insights in NAFLD pathogenesis.

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LAL activity is significantly reduced in adult patients with NAFLD, compared to healthy subjects.

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Patients with NASH disclose the lowest value of LAL activity.

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Patients with LAL activity below median have a significant elevation of serum liver enzymes and a worse lipid profile.

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Low LAL activity is associated with metabolic syndrome and lower statin use.