Gender-based differences in the relationship between fatty liver disease and atherosclerosis

The impact of insulin induced lipohypertrophy on carotid intima-media thickness in patients with type 2 diabetes mellitus

Lipohypertrophy (LH) is a major localized complication of insulin therapy. We aimed to investigate the association between insulin-induced LH and carotid intima-media thickness (CIMT) in patients with type 2 diabetes mellitus (DM). A total of 75 patients with DM treated with insulin were included in this study. The insulin injection sites of the patients were evaluated by inspection and palpation and then radiologically with ultrasound. The CIMT of the patients was evaluated using ultrasonography. According to the guideline recommendation, the CIMT cutoff value was taken as 0.9 mm, and the patients were categorized into 2 groups according to the CIMT value and evaluated statistically. The presence of LH (CI: 1.379-30.000; OR = 6.432; P < .05), age (CI: 1.036-1.149; OR = 1091; P < .05), BMI (CI: 1.003-1.262; OR = 1.125; P < .05) and duration of DM (CI: 1.001-1.300; OR = 1.141; P < .05) were independent risk factors for high-CIMT in patients with DM. The most interesting result of this study was that the presence of LH was an independent risk factor for increased CIMT. According to this result, we think that LH may increase the risk of cardiovascular disease as well as being a complication that disrupts the blood glucose regulation of patients with DM and increases the cost of treatment.

Gender Differences and Cardiometabolic Risk: The Importance of the Risk Factors

Metabolic syndrome (Mets) is a clinical condition characterized by a cluster of major risk factors for cardiovascular disease (CVD) and type 2 diabetes: proatherogenic dyslipidemia, elevated blood pressure, dysglycemia, and abdominal obesity. Each risk factor has an independent effect, but, when aggregated, they become synergistic, doubling the risk of developing cardiovascular diseases and causing a 1.5-fold increase in all-cause mortality. We will highlight gender differences in the epidemiology, etiology, pathophysiology, and clinical expression of the aforementioned Mets components. Moreover, we will discuss gender differences in new biochemical markers of metabolic syndrome and cardiovascular risk.

Shift work and nonalcoholic fatty liver disease incidence among Chinese rail workers: a 4-year longitudinal cohort study

PURPOSE

Occupational harmful factors, such as shift work, are attracting increasing attention as a potential cause of nonalcoholic fatty liver disease (NAFLD). In this study, we aimed to identify the association between shift work and NAFLD incidence in Chinese rail population.

METHODS

A cohort study was conducted among 14,112 rail workers for 4-year follow-up. Shift work frequency and other potential variables were recorded by questionnaires, including demographic, lifestyle, and occupation information. Besides, body mass index, blood pressure, fasting blood glucose, total cholesterol, triglyceride, alanine aminotransferase, and aspartate aminotransferase were measured by anthropometric measurement and blood test. Diagnosis of new NAFLD case was based on abdominal ultrasonography. Cox proportional hazards regression model was used to determine whether shift work has effect on occurrence of NAFLD.

RESULTS

The incidence of NAFLD was 30.43% in total subjects. After adjustment for possible confounders, the RRs of NAFLD were 1.069 (95% CI 0.998-1.146) and 1.179 (95% CI 1.059-1.312) in occasionally shift work group and frequently shift work group respectively, compared to the seldom shift work group. In stratified analyses, the RRs of NAFLD incidence linked to shift work exposure seems increase among female and elder. The results of three sensitivity analyses were similar with main analysis.

CONCLUSIONS

This research provided further evidence of positive harmful effect of shift work on NAFLD incidence in Chinese rail workers, particularly in frequently shift work population. The risk estimate of shift work on NAFLD was higher in female and elder.

Population-specific cut-off points of fatty liver index: a study based on the National Health and Nutrition Examination Survey data

BACKGROUND

Fatty liver index (FLI) is the most recognized blood biomarker for diagnosis of hepatic steatosis (HS), but lacks the reliable specific cut-off points (COPs). Therefore, we aim to investigate the population-specific COPs of FLI based on the results of liver ultrasound transient elastography (LUTE) and conventional ultrasonography in the National Health and Nutrition Examination Survey (NHANES).

METHODS

5948 participants who underwent LUTE from the NHANES 2017-2018 and 14,797 participants who underwent conventional ultrasonography from the Third NHANES (NHANES III) were recruited. FLI was calculated by using body mass index (BMI), waist circumference (WC), triglyceride, and gamma-glutamyl transferase, and its optimal COPs in a specific population (stratified by sex, BMI, and WC) were obtained from receiver operator characteristics (ROC) curve with ultrasonic-diagnosed HS as the reference standard.

RESULTS

Based on LUTE in NHANES 2017-2018, the prevalence of HS and metabolic dysfunction-associated fatty liver disease (MAFLD) were 58.7% and 56.2%, respectively, and the optimal COP of FLI for HS diagnosis in the overall population was 45.60, with an area under ROC curve (AUROC) of 0.833 (0.822-0.844). Based on conventional ultrasonography in NHANES III, the prevalence of HS and MAFLD were 34.4% and 27. 9%, respectively, and the optimal COP of FLI for HS was 59.5, with an AUROC of 0.681 (0.671-0.691). With the increase of BMI and WC, the COPs increased gradually with significant differences between different groups. Compared with conventional ultrasonography, the COPs of FLI based on LUTE were much more precise, with higher diagnostic ability. The population-specific COPs of FLI stratified by gender, WC, and BMI were tabulated.

CONCLUSION

In the United States, the incidences of HS and MAFLD were high, especially when assessed by LUTE. The FLI based on LUTE is well capable of predicting HS when stratified by gender, WC, and BMI.

Research status and progress of metabolic associated fatty liver disease

Metabolic associated fatty liver disease (MAFLD) is a more appropriate general predicate to describe non-alcoholic fatty liver disease. The new definition lists metabolic dysfunction as an important cause of liver disease, demonstrates the high heterogeneity of this condition, and speeds up the transformation path to new treatment. The incidence of extrahepatic complications and related diseases of MAFLD far exceed that of the liver disease itself, which seriously threatens human health. In view of the current insufficient understanding of its severity, and the imperfect understanding of the disease scope, pathogenesis, and diagnosis of extrahepatic complications, especially the lack of effective drug treatment, this paper introduces and reviews the research status and progress of extrahepatic complications of MAFLD.

Sex Differences in Nonalcoholic Fatty Liver Disease: Estrogen Influence on the Liver-Adipose Tissue Crosstalk

Significance: Nonalcoholic fatty liver disease (NAFLD) is a hepatic and systemic disorder with a complex multifactorial pathogenesis. Owing to the rising incidence of obesity and diabetes mellitus, the prevalence of NAFLD and its impact on global health care are expected to increase in the future. Differences in NAFLD exist between males and females, and among females depending on their reproductive status. Clinical and preclinical data show that females in the fertile age are more protected against NAFLD, and studies in postmenopausal women and ovariectomized animal models support a protective role for estrogens. Recent Advances: An efficient crosstalk between the liver and adipose tissue is necessary to regulate lipid and glucose metabolism, protecting the liver from steatosis and insulin resistance contributing to NALFD. New advances in the knowledge of sexual dimorphism in liver and adipose tissue are providing interesting clues about the sex differences in NAFLD pathogenesis that could inspire new therapeutic strategies. Critical Issues: Sex hormones influence key master regulators of lipid metabolism and oxidative stress in liver and adipose tissue. All these sex-biased metabolic adjustments shape the crosstalk between liver and adipose tissue, contributing to the higher protection of females to NAFLD. Future Directions: The development of novel drugs based on the protective action of estrogens, but without its feminizing or undesired side effects, might provide new therapeutic strategies for the management of NAFLD. Antioxid. Redox Signal. 35, 753-774.

The association between low-density lipoprotein cholesterol/high-density lipoprotein cholesterol ratio cholesterol ratio and thickened carotid intima-media thickness: A case-control study

BACKGROUND

It is indicated that Low-density lipoprotein cholesterol/high-density lipoprotein cholesterol ratio (LDL-C/HDL-C ratio) has greater predictive value for thickened carotid intima-media thickness (CIMT) comparing with classic lipid parameters. However, there have been few reports about their association in general Chinese population.

METHOD

We included a total of 1220 CIMT participants and 2440 matched controls, who had ultrasonography of carotid artery during 2009 and 2016. Univariate and multivariate logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for thickened CIMT risk associated with LDL-C/HDL-C ratio.

RESULT

In the univariate logistic regression model, there was significant association between LDL-C/HDL-C ratio and thickened CIMT (Q4 vs. Q1, OR = 1.94, 95% CI: 1.60-2.36; p_trend < 0.05). After adjusting for potential covariates, LDL-C/HDL-C ratio remained significantly associated with thickened CIMT (Q4 vs. Q1, OR = 1.81, 95% CI: 1.41-2.34, p_trend < 0.001; ≥3.05 v.s. <3.05, OR = 1.66, 95% CI: 1.37-2.02). In subgroup analyses, the association between LDL-C/HDL-C ratio and thickened CIMT remained significant in the subgroups stratified by sex, impaired fasting glucose (IFG), hypertension, and fatty liver disease but only remained significant in the subgroups of ≥45 years (OR = 2.01, 95% CI: 1.46-2.76; P_trend<0.05), BMI ≥24 (kg/m²) (OR = 2.22; 95% CI = 1.63-3.03; Ptrend < 0.05) and BMI ≥25 (kg/m²) (OR = 2.50, 95% CI: 1.76-3.54; P_trend < 0.05), dyslipidemia (OR = 3.28, 95% CI: 1.83-5,85; P_trend < 0.001), and without periodontitis (OR = 2.08, 95% CI: 1.54-2.81 ; Ptrend < 0.05) comparing Q4 to Q1. Similar results were observed in the subgroup analyses for LDL-C/HDL-C ratio ≥3.05 v.s. <3.05 except for the age stratification.

CONCLUSION

High LDL-C/HDL-C ratio could significantly increase the risk of thickened CIMT independent of gender, IFG, hypertension, and fatty liver disease in general Chinese population.

Cardiovascular involvement after liver transplantation: role of non-alcoholic fatty liver disease and non-alcoholic steatohepatitis

Patients submitted to liver transplantation (LT) are exposed to high risk of cardiovascular (CV) complications which are the main determinants of both short-term and long-term morbidity and mortality in LT. Non-alcoholic fatty liver disease (NAFLD) is a very frequent condition in general population and is associated with a high risk of cardiovascular disease (CVD) which represents the first cause of death of these patients. NAFLD is predicted to become the first indication to LT and nowadays is also frequently detected in patients submitted to LT for other indications. Thus, the risk of CVD in patients submitted to LT is forecasted to increase in the next years. In this review the extent of CV involvement in patients submitted to LT and the role of NAFLD, either recurring after transplantation or as de novo presentation, in increasing CV risk is analysed. The risk of developing metabolic alterations, including diabetes, hypertension, dyslipidemia and weight gain, all manifestations of metabolic syndrome, occurring in the first months after LT, is depicted. The different presentations of cardiac involvement, represented by early atherosclerosis, coronary artery disease, heart failure and arrhythmias in patients with NAFLD submitted to LT is described. In addition, the tools to detect cardiac alterations either before or after LT is reported providing the possibility for an early diagnosis of CVD and an early therapy able to reduce morbidity and mortality for these diseases. The need for long-term concerted multidisciplinary activity with dietary counseling and exercise combined with drug treatment of all manifestations of metabolic syndrome is emphasized.

Relationship between non-alcoholic fatty liver disease and cardiovascular disease

With the in-depth study of non-alcoholic fatty liver disease (NAFLD), it has been found in recent years that NAFLD is closely related to cardiovascular disease (CVD). It has been proved that NAFLD is not only an important risk factor for CVD, but it is also an important mechanism of atherosclerosis, coronary heart disease, and hypertension in young people. This article reviews the recent progress in the understanding of the relationship between NAFLD and CVD, with an aim to improve the knowledge of CVD physicians on liver disease and provide reference for prevention and treatment of these conditions.

Cardiovascular Risk in Fatty Liver Disease: The Liver-Heart Axis-Literature Review

According to the World Health Organization, cardiovascular disease (CVD) remains the leading cause of death worldwide, accounting for approximately 18 million deaths per year. Nevertheless, the worldwide prevalence of metabolic diseases, such as type 2 diabetes mellitus, obesity, and non-alcoholic fatty liver disease (NAFLD), also known to be common risk factors for CVD, have dramatically increased over the last decades. Chronic alcohol consumption is a major cause of chronic liver diseases (CLD) as well as being a major health care cost expenditure accounting for the spending of tremendous amounts of money annually. NAFLD has become one of the major diseases plaguing the world while standing as the most common cause of liver disease in the Western countries by representing about 75% of all CLD. Currently, the most common cause of death in NAFLD remains to be CVD. Several mechanisms have been suggested to be responsible for associating FLD with CVD through several mechanisms including low-grade systemic inflammation, oxidative stress, adipokines, endoplasmic reticulum stress, lipotoxicity and microbiota dysbiosis which may also be influenced by other factors such as genetic and epigenetic variations. Despite of all this evidence, the exact mechanisms of how FLD can causally contribute to CVD are not fully elucidated and much remains unknown. Moreover, the current literature supports the increasing evidence associating FLD with several cardiovascular (CV) adverse events including coronary artery disease, increased subclinical atherosclerosis risk, structural alterations mainly left ventricular hypertrophy, increased epicardial fat thickness, valvular calcifications including aortic valve sclerosis and mitral annular calcification and functional cardiac modifications mainly diastolic dysfunction in addition to cardiac arrhythmias such as atrial fibrillation and ventricular arrythmias and conduction defects including atrioventricular blocks and bundle branch blocks. Patients with FLD should be evaluated and managed accordingly in order to prevent further complications. Possible management methods include non-pharmacological strategies including life style modifications, pharmacological therapies as well as surgical management. This review aims to summarize the current state of knowledge regarding the pathophysiological mechanisms linking FLD with an increased CV risk, in addition to associated CV adverse events and current management modalities.

Clinical workup of fatty liver for the primary care provider

Nonalcoholic fatty liver disease (NAFLD) is quickly emerging as a global epidemic in parallel with the rise in obesity and the Metabolic Syndrome. NAFLD, once seen simply as a passive consequence of the Metabolic Syndrome (MetS), has been found to interact with other features of MetS to exacerbate insulin resistance, diabetes, and cardiovascular disease. NAFLD is also becoming the top indication for liver transplant and an important risk factor for hepatocellular carcinoma. Treatment of this disorder is limited mainly to lifestyle modifications to promote weight loss along with consideration for off-label use of certain medications, but recent progression in clinical trials means more effective treatments are on the horizon. Therefore, the primary care provider must be prepared to recognize and determine the severity of this disorder in order to optimize management. In this review, we will discuss risk factors for NAFLD, workup and differential, and finally, offer recommendations on screening.

Nonalcoholic Fatty Liver Disease and Coronary Artery Calcification in a Northern Chinese Population: a Cross Sectional Study

Nonalcoholic fatty liver disease (NAFLD) has become an emerging health issue with a high prevalence in general population. The cross-sectional study was performed to investigate the association between NAFLD and coronary artery calcification (CAC) in individuals from northern city of China. A total of 2345 participants aged ≥40 (1035 men and 1310 women) were selected from the Jidong community of Tangshan city. Liver ultrasonography was used to the diagnosis of NAFLD. A 64-slice CT scanner was used to determine coronary artery calcification score (CACS), with CACS > 0 defined to be the presence of CAC. The risk level of coronary heart disease (CHD) was graded by CACS according to the 4 commonly used thresholds in clinical practice (0, 10, 100, and 400 Agatston units). NAFLD was significantly associated with CAC (crude OR: 1.631, 95% CI: 1.295–2.053, adjusted OR: 1.348, 95% CI: 1.030–1.765). The association between NAFLD and increased risk level of CHD (Crude OR: 1.639 95% CI: 1.303–2.063; adjusted OR: 1.359 95% CI: 1.043–1.770) was observed. The associations between NAFLD and CAC or increased risk level of CHD were significant in female but not in male. Our finding further confirmed the association between NAFLD and CAC, especially in Asian population.

NAFLD as a Sexual Dimorphic Disease: Role of Gender and Reproductive Status in the Development and Progression of Nonalcoholic Fatty Liver Disease and Inherent Cardiovascular Risk

Nonalcoholic fatty liver disease (NAFLD) spans steatosis through nonalcoholic steatohepatis, cirrhosis, and hepatocellular carcinoma (HCC) associated with striking systemic features and excess cardiovascular and liver-related mortality. The pathogenesis of NAFLD is complex and multifactorial. Endocrine derangements are closely linked with dysmetabolic traits. For example, in animal and human studies, female sex is protected from dysmetabolism thanks to young individuals’ ability to partition fatty acids towards ketone body production rather than very low density lipoprotein (VLDL)-triacylglycerol, and to sex-specific browning of white adipose tissue. Ovarian senescence facilitates both the development of massive hepatic steatosis and the fibrotic progression of liver disease in an experimental overfed zebrafish model. Consistently, estrogen deficiency, by potentiating hepatic inflammatory changes, hastens the progression of disease in a dietary model of nonalcoholic steatohepatitis (NASH) developing in ovariectomized mice fed a high-fat diet. In humans, NAFLD more often affects men; and premenopausal women are equally protected from developing NAFLD as they are from cardiovascular disease. It would be expected that early menarche, definitely associated with estrogen activation, would produce protection against the risk of NAFLD. Nevertheless, it has been suggested that early menarche may confer an increased risk of NAFLD in adulthood, excess adiposity being the primary culprit of this association. Fertile age may be associated with more severe hepatocyte injury and inflammation, but also with a decreased risk of liver fibrosis compared to men and postmenopausal status. Later in life, ovarian senescence is strongly associated with severe steatosis and fibrosing NASH, which may occur in postmenopausal women. Estrogen deficiency is deemed to be responsible for these findings via the development of postmenopausal metabolic syndrome. Estrogen supplementation may at least theoretically protect from NAFLD development and progression, as suggested by some studies exploring the effect of hormonal replacement therapy on postmenopausal women, but the variable impact of different sex hormones in NAFLD (i.e., the pro-inflammatory effect of progesterone) should be carefully considered.