Association between non-alcoholic fatty liver disease and arterial stiffness in the non-obese, non-hypertensive, and non-diabetic young and middle-aged Chinese population

Predictors of High Cardiovascular Risk Among Nonobese Patients with Type 2 Diabetes and Non-Alcoholic Fatty Liver Disease in a Chinese Population

Purpose

This study aims to investigate cardiovascular risk factors in nonobese patients with type 2 diabetes (T2DM) and non-alcoholic fatty liver disease (NAFLD) and to determine whether they might be used to predict high-risk individuals effectively.

Patients and Methods

This cross-sectional study included 245 nonobese patients with T2DM who underwent FibroTouch in the National Metabolic Management Center of the Affiliated Changzhou No. 2 People's Hospital of Nanjing Medical University from January 2021 to December 2022. All individuals were divided into NAFLD and non-NAFLD groups. Patients with NAFLD were further grouped by UAP tertiles (T1, T2 and T3). We created a Cardiovascular Score (total scale: 0-5 points; ≥3 points was defined as high-risk individual) based on baPWV, carotid ultrasound, and urinary microalbumin creatinine ratio (UA/CR) to assess the risk of cardiovascular disease in non-obese T2DM patients with NAFLD. Risk factors were evaluated using univariate and multivariate analysis. The performance of risk factors was compared according to the area under the receiver operating characteristic (ROC) curve.

Results

Atherogenic index of plasma (AIP), atherosclerosis index (AI), prevalence of hypertension, body mass index (BMI) and homeostatic model assessment of insulin resistance (HOMA-IR) were higher in the NAFLD group compared to the non-NAFLD group. In T3 group, AIP, AI, BMI and HOMA-IR were higher than those of T1 group. Multivariate logistic regression showed that age, systolic blood pressure, low-density lipoprotein-cholesterol (LDL-C) and AIP were risk factors for cardiovascular disease among nonobese patients with T2DM and NAFLD. The area under the ROC curve for age, systolic blood pressure, LDL-C and AIP were 0.705, 0.688, 0.738 and 0.642, respectively. The area under the ROC curve was 0.895 when combining them.

Conclusion

Age, systolic blood pressure, AIP and LDL-C are all independent risk factors for cardiovascular disease in non-obese individuals with T2DM and NAFLD, which can be combined to identify high-risk populations and carry out intervention.

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.

Usefulness of controlled attenuation parameter and liver stiffness measurement for detecting increased arterial stiffness in asymptomatic populations in China

In recent studies, vibration-controlled transient elastography (FibroScan) has been reported as an alternative noninvasive approach for measuring liver steatosis and fibrosis. The present study aimed to investigate the feasibility of FibroScan controlled attenuation parameter (CAP) and liver stiffness measurement (LSM) in the detection of increased arterial stiffness in asymptomatic populations in China.A retrospective cohort recruiting 4747 asymptomatic patients with no underlying causes of liver disease and having FibroScan and brachial-ankle pulse wave velocity (baPWV) during wellness check-up was covered. Nonalcoholic fatty liver disease (NAFLD) was defined as a CAP ≥238 dB/m. NAFLD with significant fibrosis was defined as an LSM ≥7.3 kPa in the presence of NAFLD. Increased arterial stiffness was determined as a BaPWV ≥1.4m/second.Among the 4747 study participants, 1596 subjects (33.6%) suffered from increased arterial stiffness. The prevalence of increased arterial stiffness progressively increased across CAP quartiles and LSM quartiles in NAFLD (23.5%, 30.8%, 38.3%, 43.7%, P < .001 and 33.1%, 36.8%, 40.4%, 48.2%, P < .001, respectively). After conventional cardiovascular risk factors were adjusted (age, sex, overweight, diabetes mellitus, hypertension, hypercholesterolemia, and current smoking habits), multivariate logistic regression analysis revealed that CAP (odd ratio [OR] = 1.005; 95% confidence interval [CI]: 1.003-1.006; P < .001), NAFLD (OR = 1.427; 95% CI: 1.212-1.681; P < .001), LSM in NAFLD (OR = 1.073; 95% CI: 1.023-1.125; P = .003), and significant fibrosis in NAFLD (OR = 1.480; 95% CI: 1.090-2.010; P = .012) were independently associated with increased arterial stiffness. Furthermore, in a multivariate logistic regression analysis, OR (95% CI) for the maximal vs. the minimal quartile of CAP was 1.602 (1.268-2.024), and that of LSM in NAFLD was 1.362 (1.034-1.792) after adjustment for the above-mentioned risk factors. Notably, NAFLD and significant fibrosis in NAFLD were significantly correlated only with increased arterial stiffness in subjects without hypertension or diabetes mellitus after adjustment for the above-mentioned risk factors.CAP-defined NAFLD and LSM-defined significant fibrosis in NAFLD showed significant and independent relationships with increased arterial stiffness even after adjustment for conventional cardiovascular risk factors, which can be conducive to stratifying relative risk of subjects having undergone screening assessment for cardiovascular disease.

Nonalcoholic fatty liver disease in lean subjects: Prognosis, outcomes and management

Nonalcoholic fatty liver disease (NAFLD) accounts for most cases of chronic liver disease worldwide, with an estimated global prevalence of approximately 25% and ranges from simple steatosis to nonalcoholic steatohepatitis and cirrhosis. NAFLD is strongly connected to metabolic syndrome, and for many years, fatty liver was considered to be an exclusive feature of obese patients. However, recent studies have highlighted the presence of NAFLD in non-obese subjects, with or without increased visceral fat or even in lean subjects without increased waist circumference. “Lean NAFLD” is a relatively new concept and there is significant scientific interest in understanding the differences in pathophysiology, prognosis and management compared with NAFLD in overweight/obese patients. In the present editorial, we discuss the clinical and metabolic profiles and outcomes of lean NAFLD compared with both obese NAFLD and lean healthy individuals from Asian and Western countries. Moreover, we shed light to the challenging topic of management of NAFLD in lean subjects since there are no specific guidelines for this population. Finally, we discuss open questions and issues to be addressed in the future in order to categorize NAFLD patients into lean and non-lean cohorts.

About 1/3rd of north Indian patients less than 50 years of age with type 2 diabetes have high pulse wave velocity indicating high risk of atherosclerosis

BACKGROUND AND AIMS

Asian Indian patients with type 2 diabetes mellitus (T2DM) have a high cardiovascular risk even at young age. There is a need to assess this increased risk and identify atherosclerosis early so that appropriate measures for risk reduction can be taken. We aimed to study carotid-femoral pulse wave velocity (Cf-PWV), a non-invasive indicator of atherosclerosis, in patients with diabetes below 50 years of age and its correlation with markers of obesity and other cardiovascular risk factors.

METHODS

Patients (n, 299) with T2DM below 50 years of age underwent measurement of Cf-PWV by applanation tonometry. Anthropometric parameters, blood pressure, liver span, glycosylated hemoglobin, serum lipid profile, urinary microalbumin, ankle brachial index and carotid intima media thickness were measured.

RESULTS

Data show that 32.4% of patients had high Cf-PWV, with mean values higher in males than females. On stepwise multiple linear regression analysis, the significant independent determinants of PWV were age, systolic blood pressure, waist circumference, microalbumin and liver span.

CONCLUSION

About one third patients with T2DM less than 50 years of age, in north India have increased arterial stiffness which correlates with blood pressure, abdominal obesity, liver size and microalbumin, indicating increased risk for coronary artery disease.

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.

Nonalcoholic Fatty Liver Disease and Coronary Artery Disease: Big Brothers in Patients with Acute Coronary Syndrome

Background

The prevalence of nonalcoholic fatty liver disease (NAFLD) has been increasing. This study aimed to evaluate the prevalence of NAFLD, as diagnosed by ultrasound, in patients with acute coronary syndrome (ACS) and to assess whether NAFLD is associated with the severity of coronary obstruction as diagnosed by coronary angiography.

Methods

We performed a prospective single-center study in patients hospitalized due to acute coronary syndrome who underwent diagnostic coronary angiography. Consecutive patients who presented to the emergency room were diagnosed with acute coronary syndrome and were included. All patients underwent ultrasonography of the upper abdomen to determine the presence or absence of NAFLD; NAFLD severity was graded from 0 to 3 based on a previously validated scale. All patients underwent diagnostic coronary angiography in the same hospital, with the same team of interventional cardiologists, who were blinded to the patients' clinical and ultrasonographic data. CAD was then angiographically graded from none to severe based on well-established angiographic criteria.

Results

This study included 139 patients, of whom 83 (59.7%) were male, with a mean age of 59.7 years. Of the included patients, 107 (77%) patients had CAD, 63 (45%) with serious injury. Regarding the presence of NAFLD, 76 (55.2%) had NAFLD including 18 (23.6%) with grade III disease. In severe CAD, 47 (60.5%) are associated with NAFLD, and 15 (83.3%) of the patients had severe CAD and NAFLD grade III.

Conclusions

NAFLD is common in patients with ACS. The intensity of NAFLD detected by ultrasonography is strongly associated with the severity of coronary artery obstruction on angiography.

The Prevalence of Lean/Nonobese Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis

BACKGROUND AND AIM

The prevalence of lean/nonobese nonalcoholic fatty liver disease (NAFLD) ranges widely in studies. Thus, here, we aimed to perform a meta-analysis on NAFLD prevalence in the lean or nonobese population to give clarity.

MATERIALS AND METHODS

PubMed, Embase, and the Cochrane Library databases were systematically searched to identify studies reporting NAFLD prevalence in the lean/nonobese population. Lean or nonobese was defined by body mass index cutoffs reported by authors in original studies. NAFLD prevalence based on community, population, or health checkups was combined with random-effect model after logit transformation. Subgroup analysis and meta-regression were further performed to investigate the heterogenicity.

RESULTS

A total of 45 studies were enrolled in the final analysis, with 55,936 lean/nonobese subjects included, among whom 7351 NAFLD patients were diagnosed. Overall, the pooled NAFLD prevalence of the lean or nonobese population was 10.2% (95% confidence interval: 7.6%-13.6%) and 15.7% (95% confidence interval: 12.5%-19.6%), respectively. Compared with western studies, the NAFLD prevalence in the lean or nonobese population was lower in eastern studies. In addition, the NAFLD prevalence in both the lean and nonobese population showed a general upward trend during recent years. The prevalence was similar in community-based and health checkup-based studies. Lean/nonobese NAFLD patients had significantly lower rates of hypertension, lower uric acid and fasting plasma glucose, and a higher level of high-density lipoprotein than nonlean/obese patients.

CONCLUSIONS

The prevalence of NAFLD in the lean/nonobese population is not rare in either the western or eastern regions of the world. This meta-analysis of prevalence assessment and clinical characteristics should enable higher confidence in more specific interventions and health care standards for these patients.

Non-alcoholic fatty liver disease-From the cardiologist perspective

Non-alcoholic fatty liver disease (NAFLD) includes a range of disorders characterized by excess accumulation of triglycerides within the liver. While simple steatosis may be clinically stable, non-alcoholic steatohepatitis (NASH) can be progressive. Inflammation is believed to be the driving force behind NASH and the progression to fibrosis and subsequent cirrhosis. NAFLD is globally considered a significant health concern not only because of its incidence but also because of its economic impact. The fact that NAFLD is associated with cardiovascular disease is widely recognized, as well as the fact that NAFLD patient mortality rises when such an association is present. In particular, NAFLD is associated with coronary and carotid atherosclerosis, endothelial dysfunction and arterial rigidity, ventricles function, valves morphology, congestive heart failure, and arrhythmias (especially atrial fibrillation). Additionally, the hypercoagulability status in NAFLD patient may be suggested by the presence of inflammatory and coagulation markers. In order to differentiate between milder forms and the more severe ones that necessitate aggressive therapy, individualized risk scores may be used. This narrative review will analyze and interpret the papers published in PubMed in the last 16 years, in an attempt to expand our understanding of the NASH as a possible cardiovascular risk factor.

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.

Non-alcoholic fatty liver disease and hypertension: coprevalent or correlated?

OBJECTIVE

To provide a comprehensive review summarizing the existing evidence on the association between nonalcoholic fatty liver disease (NAFLD) and hypertension (HT) independent of other components of metabolic syndrome.

METHODS

We searched the literature through Medline and the Cochrane Library for studies evaluating the relationship between hypertension and fatty liver disease.

RESULTS

Studies testing this association are limited, but agree that HT and fatty liver disease are inter-related independent of other components of the metabolic syndrome such as obesity and diabetes mellitus. Clinical evidence shows that NAFLD is associated with new-onset HT, whereas increased blood pressure is related to the development of fatty liver disease and the possible subsequent progression to liver fibrosis. Insulin resistance and activation of the renin-angiotensin-aldosterone system (RAAS) might provide potential pathophysiologic links between these clinical entities. Until further evidence is available, patients with HT should be meticulously evaluated and treated for fatty liver disease and vice versa. RAAS inhibitors have been tested in NAFLD, presenting a favorable profile by decreasing insulin resistance and fibrosis progression.

CONCLUSION

NAFLD and HT are associated independent of traditional cardiovascular risk factors. Insulin resistance appears to be the main linking mechanism. Although RAAS inhibitors are the most beneficial treatment option for HT in patients with NAFLD, randomized studies on the administration of these agents in HT patients with NAFDL are warranted to provide optimal treatment options in these high cardiovascular risk individuals.

Fatty liver index is associated to pulse wave velocity in healthy subjects: Data from the Brisighella Heart Study

BACKGROUND

Non-Alcoholic Fatty Liver Disease (NAFLD) is associated to increased risk of cardiovascular disease. Our aim was to evaluate association of indexes of fatty liver with arterial stiffness (AS).

METHODS

We analyzed data of adult volunteers visited during the last Brisighella survey. We evaluated the Pulse Wave Velocity (PWV) and the following non-invasive indexes of liver steatosis: Fatty Liver Index (FLI), Lipid Accumulation Product (LAP), Hepatic Steatosis Index (HSI). We compared patients according to the risk of Non-Alcoholic Steatohepatitis (NASH): low-risk (BMI < 28 and no diabetes), intermediate-risk (BMI ≥ 28 or diabetes), high-risk (BMI ≥ 28 and diabetes). Multiple Linear Regression analysis was assessed for predictors of AS.

RESULTS

We studied 1731 volunteers. In subjects with low metabolic risk, HSI (RR = 0.138, 95%CI 0.105-0.170, p < 0.001), FLI (RR = 0.024, 95%CI 0.016-0.032, p < 0.001), LAP (RR = 0.014, 95%CI 0.008-0.020, p < 0.001) and Serum Uric Acid (RR = 0.150, 95%CI 0.024-0.275, p = 0.019) were significant predictors of AS. HSI and FLI emerged as predictors of PWV in intermediate risk group (RR = 0.116, 95%CI 0.071-0.160, p < 0.001; RR = 0.010, 95%CI 0.001-0.020, p = 0.041). In volunteers with high risk, FLI and Uric Acid were related to PWV (RR = 0.049, 95%CI 0.011-0.087, p = 0.013; RR = 0.632, 95% CI 0.222-1.041, p = 0.003).

CONCLUSION

Fatty liver indirect indexes were associated to AS in subjects with different metabolic risk profiles.

Increased arterial stiffness in nonalcoholic fatty liver disease: a systematic review and meta-analysis

BACKGROUND

Arterial function is a marker of early atherosclerotic changes and cardiovascular disease. Several studies have suggested the possible association between nonalcoholic fatty liver disease (NAFLD) and increased arterial stiffness. Thus, we conducted a systematic review and meta-analysis to better characterize this association.

PATIENTS AND METHODS

A comprehensive search of the databases of the MEDLINE and EMBASE was carried out from inception through September 2016. All observational studies that compared arterial stiffness between NAFLD patients and healthy controls were included. Arterial stiffness was measured by pulse wave velocity (PWV) and augmentation index. We calculated pooled mean difference (MD) with 95% confidence intervals (CIs) using the random-effects model.

RESULTS

Data were extracted from 12 studies involving 9351 NAFLD patients and 17 684 controls. NAFLD is significantly associated with increased arterial stiffness as determined by carotid-femoral PWV (MD=0.75 m/s, 95% CI: 0.43-1.07, I=88%), brachial-ankle PWV (MD=0.82 m/s, 95% CI: 0.57-1.07, I=92%), and augmentation index (pooled MD=2.54%, 95% CI: 0.07-5.01, I=73%) compared with healthy controls.

CONCLUSION

In conclusion, our study demonstrated a higher degree of arterial stiffness in NAFLD patients compared with controls. However, this association might be related to the higher prevalence of cardiometabolic risk factors in NAFLD patients. Further studies are needed to determine an independent association between NAFLD and arterial stiffness adjusting to cardiometabolic risks.

Hypertension and non-alcoholic fatty liver disease proven by transient elastography

AIM

The relationship between non-alcoholic fatty liver disease (NAFLD) and hypertension is poorly understood. In the present study, we aimed to assess the relationship between essential hypertension and NAFLD, by using a new diagnostic tool, transient elastography (TE).

METHODS

We enrolled 836 subjects in this study. All subjects underwent a comprehensive questionnaire survey and blood test. Each patient had undergone TE to detect the controlled attenuation parameter, which was used to and quantify liver steatosis with the help of TE.

RESULTS

Participants with hypertension showed a higher prevalence of NAFLD defined by TE (P < 0.05). After adjusting for body mass index (BMI), aspartate aminotransferase (AST), alanine aminotransferase, triglycerides, total cholesterol, and high-density lipoprotein cholesterol, the odds ratio for NAFLD, comparing the grade 3 group (systolic blood pressure level ≥ 180 mmHg and/or diastolic blood pressure level ≥ 110 mmHg) with the normal group, was 1.476 (95% confidence interval, 1.166-2.551). A stepwise multivariate linear regression analysis (R²  = 0.084, P = 0.043) retained NAFLD, BMI, and AST as significant predictors of the systolic blood pressure levels. Additionally, stepwise multivariate linear regression analysis (R²  = 0.199, P = 0.037) retained NAFLD, controlled attenuation parameter, BMI, triglycerides, and high-density lipoprotein cholesterol as significant predictors of diastolic blood pressure levels. In addition, BMI, AST, and alanine aminotransferase were associated with systolic blood pressure levels among individuals with NAFLD; BMI, AST, and total cholesterol were associated with diastolic blood pressure levels among individuals with NAFLD.

CONCLUSION

The main finding of our study is that hypertensive patients have a higher prevalence of NAFLD defined by TE, and NAFLD is independently associated with hypertension and blood pressure category.

Large artery stiffness is associated with gamma-glutamyltransferase in young, healthy adults: The African-PREDICT study

Increased arterial stiffness is linked to cardiovascular disease development, particularly in black populations. Since detrimental health behaviors in young adults may affect arterial stiffness, we determined whether arterial stiffness associates with specific health behaviors, and whether it is more pronounced in young healthy black compared to white adults. We included 373 participants (49% black, 42% men) aged 20-30 years. Mean arterial pressure was higher for blacks than whites (P < .001), but carotid-femoral pulse wave velocity was similar (6.37 vs. 6.36 m/s; P = .89) after adjustment for mean arterial pressure. The black group had higher gamma-glutamyltransferase (GGT) (P < .001), cotinine, reactive oxygen species, interleukin-6, and monocyte-chemoattractant protein-1 (all P ≤ .017). Pulse wave velocity related positively and independently to GGT in both groups before and after multiple adjustments (both β = 0.15; P ≤ .049). Blacks had an unfavorable vascular profile and higher GGT, possibly indicating a higher vulnerability to cardiovascular disease development, including changes in arterial stiffness. However, this observation needs confirmation.

Increasing aortic stiffness is predictive of advanced liver fibrosis in patients with type 2 diabetes: the Rio-T2DM cohort study

BACKGROUND & AIMS

Type 2 diabetes mellitus (T2DM) is a risk factor for cardiovascular disease (CVD) and advanced stages of non-alcoholic fatty liver disease (NAFLD). The aim was to evaluate the association between aortic stiffness, a preclinical CVD marker, with advanced liver fibrosis identified by transient elastography (TE) in T2DM outpatients with NAFLD.

METHODS

This longitudinal study included 291 T2DM patients with NAFLD detected by ultrasonography, who had two carotid-femoral pulse wave velocity (cf-PWV) measurements and a TE examination (Fibroscan(®) ) performed over a median follow-up of 7 years. Advanced liver fibrosis (corresponding to ≥ F3 stage) was considered as median values >7.9 kPa (M probe) or >7.2 kPa (XL probe). Increased aortic stiffness was defined as cf-PWV >10 m/s.

RESULTS

Eighty patients (27.5%) had advanced liver fibrosis. Overall, there was an increase in cf-PWV of 0.1 m/s/year (1% per year). Both a high aortic stiffness at the 2nd cf-PWV examination [odds ratios (OR): 3.0; 95% CI: 1.3-7.2; P = 0.011] and a serial increase in aortic stiffness (OR: 2.1; 95% CI: 1.0-4.3; P = 0.046) were associated with increased odds of having advanced liver fibrosis. Patients who presented either an increase in aortic stiffness or persisted with high values had significantly higher mean liver stiffness than those who either decreased aortic stiffness or persisted with normal cf-PWV values (mean difference: 2.1 kPa, 95% CI: 0.5-3.7 kPa, P = 0.012), after adjustments for anthropometric-demographic and clinical laboratory covariates.

CONCLUSIONS

In T2DM patients with NAFLD, a high or increasing aortic stiffness predicted development of advanced liver fibrosis on TE.

NAFLD and Increased Aortic Stiffness: Parallel or Common Physiopathological Mechanisms?

Non-alcoholic fatty liver disease (NAFLD) has become the leading cause of chronic liver diseases worldwide. Liver inflammation and fibrosis related to NAFLD contribute to disease progression and increasing liver-related mortality and morbidity. Increasing data suggest that NAFLD may be linked to atherosclerotic vascular disease independent of other established cardiovascular risk factors. Central arterial stiffness has been recognized as a measure of cumulative cardiovascular risk marker load, and the measure of carotid-femoral pulse wave velocity (cf-PWV) is regarded as the gold standard assessment of aortic stiffness. It has been shown that increased aortic stiffness predicts cardiovascular morbidity and mortality in several clinical settings, including type 2 diabetes mellitus, a well-known condition associated with advanced stages of NAFLD. Furthermore, recently-published studies reported a strong association between NAFLD and increased arterial stiffness, suggesting a possible link in the pathogenesis of atherosclerosis and NAFLD. We sought to review the published data on the associations between NAFLD and aortic stiffness, in order to better understand the interplay between these two conditions and identify possible common physiopathological mechanisms.

Pitavastatin calcium improves endothelial function and delays the progress of atherosclerosis in patients with hypercholesterolemia

BACKGROUND

Statins have proven efficacy in inhibiting the onset and progress of atherosclerosis. The effectiveness of pitavastatin in reversing carotid atherosclerosis associated with hypercholesterolemia (HC) is unknown.

OBJECTIVES

To explore the simultaneous effects of pitavastatin calcium on brachial arterial flow-mediated vasodilatation (FMD), carotid intima-media thickness (IMT), and arterial stiffness (β), three surrogate markers of atherosclerosis were studied in HC patients.

METHODS

A randomized, double-blind trial was performed with 40 HC subjects who fulfilled the inclusion/exclusion criteria. Patients were given pitavastatin calcium 1 mg/d (Group 1) or 2 mg/d (Group 2) for 8 weeks. There were 20 patients in each group, and 30 gender- and age-matched healthy subjects as controls were recruited. FMD of the brachial artery, carotid IMT, and arterial stiffness indicated by β were measured at baseline and at 8 weeks after starting pitavastatin calcium therapy using ultrasound techniques. Biochemical tests were also made on all subjects.

RESULTS

At baseline, higher total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C), reduced FMD, and increased β and IMT were observed in HC patients (P<0.001 for all) compared with controls. After 8 weeks, TC was decreased by 20.59%/27.56% and LDL-C 30.92%/35.64%, respectively, in comparison to baseline groups; the HC groups had reduced β and improved endothelial function over the 8-week follow-up (P<0.05-0.001); nonetheless, no significant alterations of IMT were found (P>0.05). Significant negative interactions between TC/LDL and FMD (P<0.05-0.001), positive interactions between TC and IMT (P=0.003) and between TC/LDL and β (P<0.001-0.000) were found.

CONCLUSIONS

Treatment with pitavastatin calcium exerted favorable effects on endothelial function and arterial stiffness. It also improved carotid atherosclerosis in patients with HC.

Normal weight dyslipidemia: Is it all about the liver?

OBJECTIVE

The liver coordinates lipid metabolism and may play a vital role in the development of dyslipidemia, even in the absence of obesity. Normal weight dyslipidemia (NWD) and patients with nonalcoholic fatty liver disease (NAFLD) who do not have obesity constitute a unique subset of individuals characterized by dyslipidemia and metabolic deterioration. This review examined the available literature on the role of the liver in dyslipidemia and the metabolic characteristics of patients with NAFLD who do not have obesity.

METHODS

PubMed was searched using the following keywords: nonobese, dyslipidemia, NAFLD, NWD, liver, and metabolically obese/unhealthy normal weight. Additionally, article bibliographies were screened, and relevant citations were retrieved. Studies were excluded if they had not measured relevant biomarkers of dyslipidemia.

RESULTS

NWD and NAFLD without obesity share a similar abnormal metabolic profile. When compared with patients with NAFLD who have obesity, the metabolic abnormalities of NAFLD without obesity are similar or less severe. Furthermore, hepatic lesions develop independent of obesity, and the extent of dyslipidemia seems comparable.

CONCLUSIONS

NAFLD may impair hepatic lipid handling, causing faulty lipid homeostasis, and serves as a likely starting point for initiation and propagation of dyslipidemia along with associated comorbidities in patients without obesity.

Cardiovascular risk across the histological spectrum and the clinical manifestations of non-alcoholic fatty liver disease: An update

Non-alcoholic fatty liver disease (NAFLD) is considered to be an independent cardiovascular disease (CVD) risk factor. However, simple steatosis has a benign clinical course without excess mortality. In contrast, the advanced form of NAFLD, non-alcoholic steatohepatitis (NASH) with liver fibrosis increases mortality by approximately 70%, due to an increase in CVD mortality by approximately 300%. Chronic kidney disease (CKD) may be caused by NAFLD/NASH and it substantially increases CVD risk, especially in the presence of type 2 diabetes mellitus. Moreover, CKD may trigger NAFLD/NASH deterioration in a vicious cycle. NAFLD/NASH is also related to increased arterial stiffness (AS), an independent CVD risk factor that further raises CVD risk. Diagnosis of advanced liver fibrosis (mainly by simple non-invasive tests), CKD, and increased AS should be made early in the course of NAFLD and treated appropriately. Lifestyle measures and statin treatment may help resolve NAFLD/NASH and beneficially affect the CVD risk factors mentioned above.

Nonalcoholic fatty liver disease as a risk factor of arterial stiffness measured by the cardioankle vascular index

Nonalcoholic fatty liver disease (NAFLD) is associated with risk factors for cardiovascular disease. The cardioankle vascular index (CAVI), a new measure of arterial stiffness, was recently developed and is independent of blood pressure. We investigated whether NAFLD is associated with arterial stiffness as measured using the CAVI in an apparently healthy population.A total of 2954 subjects without any known liver diseases were enrolled. NAFLD was diagnosed via typical ultrasonography. The clinical characteristics examined included age, sex, body mass index (BMI), waist circumference (WC), and the levels of aspartate aminotransferase, alanine aminotransferase, total cholesterol, high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol triglycerides, and glucose. Arterial stiffness was defined using an age- and sex-specific threshold of the upper quartile of the CAVI.NAFLD was found in 1249 (42.3%) of the analyzed subjects. Using an age-, sex-, and BMI-adjusted model, NAFLD was associated with a 42% increase in the risk for arterial stiffness (highest quartile of the CAVI). The risk for arterial stiffness increased according to the severity of NAFLD (adjusted odds ratio [95% confidence interval], 1.27 [1.02 - 1.57] vs 1.78 [1.37 - 2.31], mild vs moderate-to-severe, respectively). When adjusted for other risk factors, including BMI, WC, smoking status, diabetes, and hypertension, these relationships remained statistically significant.Patients with NAFLD are at a high risk for arterial stiffness regardless of classical risk factors. The presence of cardiometabolic risk factors may attenuate the prediction of arterial stiffness by means of NAFLD presence. Thus, physicians should carefully assess subjects with NAFLD for atherosclerosis and associated comorbidities.