Relationship between serum adiponectin concentration, pulse wave velocity and nonalcoholic fatty liver disease

Association between De Ritis ratio and intraoperative blood transfusion in patients undergoing surgical clipping of unruptured intracranial aneurysms: a single center, retrospective, propensity score-matched study

BACKGROUND

Although elective surgery for unruptured intracranial aneurysms (UIA) has increased, few studies have evaluated the risk factors for transfusion during UIA surgery. We evaluated the association between the preoperative De Ritis ratio (aspartate transaminase/alanine transaminase) and the incidence of intraoperative transfusion in patients who had undergone surgical UIA clipping.

METHODS

Patients who underwent surgical clipping of UIA were stratified into two groups according to the preoperative De Ritis ratio cutoff levels (< 1.54 and ≥ 1.54), and the propensity score (PS)-matching analysis was performed to compare the incidence of intraoperative transfusion. Logistic regression analyses were performed to determine the risk factors for intraoperative transfusion. Net reclassification improvement (NRI) and integrated discrimination improvement (IDI) analyses were performed to verify the improvement in the intraoperative transfusion predictive model upon addition of the De Ritis ratio.

RESULTS

Intraoperative transfusion incidence was 15.4% (77/502). We observed significant differences in the incidence of intraoperative transfusion (16.2% vs. 39.7%, P = 0.004) between the groups after matching. In the logistic regression analyses, the De Ritis ratio ≥ 1.54 was an independent risk factor for transfusion (odds ratio [OR]: 3.04, 95% CI [1.53, 6.03], P = 0.002). Preoperative hemoglobin (Hb) value was a risk factor for transfusion (OR: 0.33, 95% CI [0.24, 0.47], P < 0.001). NRI and IDI analyses showed that the De Ritis ratio improved the intraoperative blood transfusion predictive models (P = 0.031 and P = 0.049, respectively).

CONCLUSIONS

De Ritis ratio maybe a significant risk factor for intraoperative transfusion in UIA surgery.

Inflammation and Bone Turnover Markers in Adult Obesity

Obesity is a condition of abnormally increased body fat resulting from increased energy intake relative to energy expenditure. Excess body weight is a risk factor for many somatic and psychological disorders, including cardiovascular disease, type 2 diabetes mellitus, osteoarthritis, and cancer types. Bone metabolism, bone turnover, and mineral content are altered in severe obesity. This review will focus on the relationship between inflammation and bone biomarkers in adult obesity.

AST to ALT ratio and arterial stiffness in non-fatty liver Japanese population:a secondary analysis based on a cross-sectional study

Background

Previous studies have revealed that triglyceride to high-density lipoprotein cholesterol (HDL-C) ratio (henceforth TG/HDL-C) is one of the major risk factors for cardiovascular disease, insulin resistance and metabolism syndrome. However, there are fewer investigations of the correlations between the aspartate aminotransferase (AST) to alanine aminotransferase (ALT) ratio and brachial ankle pulse wave velocity (baPWV). This study was undertaken to investigate the relationship between the AST to ALT ratio and brachial-ankle pulse wave velocity (baPWV) in a Japanese population.

Methods

The present study was a cross-sectional study. A total of 646 Japanese men and women without fatty liver, aged 24—84 years old, received a health medical check-up programme including the results from baPWV inspection and various standardized questionnaires in a health examination centre in Japan. Main outcome measures included AST/ALT ratio, baPWV, fatty liver and postmenopausal status. Abdominal ultrasonography was used to diagnose fatty liver. A postmenopausal state was defined as beginning 1 year following the cessation of menses.

Results

After adjusting for potential confounders (age, sex, BMI, SBP, DBP, AST, ALT, GGT, uric acid, fasting glucose, TC, LDL, eGFR, smoking and exercise statuses, fatty liver, alcohol consumption and ABI), a non-linear relationship was detected between AST/ALT and baPWV, which had an inflection point of 5.6. The effect sizes and the confidence intervals on the left and right sides of the inflection point were 12.7 (1.9 to 23.5) and − 16.7 (− 36.8 to 3.3), respectively. Subgroup analysis in participants with excessive alcohol consumption (more than 280 g/week) showed that AST/ALT had a negative correlation with baPWV (β = − 30.7, 95%CI (− 53.1, − 8.4)), and the P value for the interaction was less than 0.05.

Conclusion

The relationship between AST/ALT and baPWV is non-linear. AST/ALT was positively correlated with baPWV when AST/ALT was less than 5.6. In addition, the trend was the opposite in subjects who consumed excessive amounts of alcohol.

Effects of chronic hepatitis C infection on arterial stiffness

Nonalcoholic fatty liver disease (NAFLD) is associated with increased arterial stiffness. Although chronic hepatitis C virus (HCV) infection was shown to be associated with metabolic disorder and chronic inflammation, the effects of chronic HCV infection on arterial stiffness remain unclear. This study recruited 221 patients including 32 normal controls, 72 NAFLD patients, and 117 subjects with HCV infection. Arterial stiffness was assessed by peripheral arterial stiffness index, Compliance Index (CI), and central arterial stiffness index, Stiffness Index derived from digital volume pulse by photoplethysmography. Levels of oxidative stress marker and inflammatory markers were also measured. The HCV group had significantly lower CI (4.8 ± 3.1 units vs. 3.9 ± 2.1 units vs. 3.0 ± 1.7 units; P for trend <.001) and higher Stiffness Index (7.0 ± 1.6 m/s vs. 8.3 ± 2.3 m/s vs. 8.4 ± 2.3 m/s; P for trend = .001) compared with the normal controls and NAFLD groups. Multivariate linear regression analysis showed that CI was independently correlated with systolic blood pressure (beta = -0.202, P = .013) and HCV infection (beta = -0.216, P = .036). Chronic HCV infection was independently associated with peripheral arterial stiffness. Peripheral arterial stiffness in chronic HCV infection was not associated with a marker of general inflammation (high-sensitivity C-reactive protein); however, a role for more specific markers of inflammation cannot be ruled out.

The synergistic impact of nonalcoholic fatty liver disease and metabolic syndrome on subclinical atherosclerosis

OBJECTIVE

Nonalcoholic fatty liver disease (NAFLD) is a well-known contributor for the development of cardiovascular disease (CVD). We examined the influence of NAFLD and metabolic syndrome (MetS) on markers of subclinical atherosclerosis, including carotid intima-media thickness (CIMT), brachial-ankle pulse wave velocity (baPWV) and ankle-brachial pressure index (ABI), after adjusting for cardiometabolic risk factors.

DESIGN

A cross-sectional study.

PATIENTS AND MEASUREMENTS

The association between NAFLD, MetS and markers of subclinical atherosclerosis was assessed in 955 participants without CVD using multiple logistic regression analysis after adjusting for multiple cardiometabolic risk variables.

RESULTS

After adjusting for age and sex, CIMT and baPWV were found to be significantly correlated with multiple cardiometabolic risk variables, whereas ABI was only associated with obesity parameters. The prevalence of NAFLD differed significantly according to the presence of subclinical atherosclerosis as defined by both CIMT and baPWV (P = 0·004 and P = 0·007, respectively). After adjusting for potential confounding factors, NAFLD or MetS was not associated with subclinical atherosclerosis as defined by CIMT and baPWV. However, individuals with both NAFLD and MetS had a significantly higher risk of subclinical atherosclerosis as defined by CIMT (OR = 2·06, 95% CI = 1·13-3·74) or baPWV (OR = 2·64, 95% CI = 1·46-4·76) compared to normal subjects, even after adjusting for potential confounders.

CONCLUSIONS

The results show that NAFLD and MetS have a synergistic impact on the subclinical atherosclerosis, which suggests that individuals with both NAFLD and MetS should be strongly advised to engage in CVD prevention strategies.

Non-alcoholic fatty liver disease associated with increased arterial stiffness in subjects with normal glucose tolerance, but not pre-diabetes and diabetes

AIM

To evaluate the association between non-alcoholic fatty liver disease and arterial stiffness in adults with normal glucose tolerance, pre-diabetes and newly diagnosed diabetes after excluding known diabetes.

METHODS

A total of 4860 subjects were divided into normal glucose tolerance, pre-diabetes and newly diagnosed diabetes groups according to the American Diabetes Association 2011 diagnostic criteria. The severity of non-alcoholic fatty liver disease was divided into mild and moderate to severe. Increased arterial stiffness was defined as brachial-ankle pulse wave velocity (baPWV) ⩾ 1400 cm/s.

RESULTS

There was a significant difference in the prevalence of mild and moderate to severe non-alcoholic fatty liver disease between subjects with and without increased arterial stiffness. Mild (odds ratio (OR) = 2.02, 95% confidence interval (CI) = 1.43-2.84) and moderate to severe (OR = 2.15, 95% CI = 1.33-3.46) non-alcoholic fatty liver disease were independently associated with increased arterial stiffness in the normal glucose tolerance group. In the pre-diabetes and diabetes groups, neither mild nor moderate to severe non-alcoholic fatty liver disease was associated with increased arterial stiffness.

CONCLUSION

The effect of non-alcoholic fatty liver disease on arterial stiffness is apparent in subjects with normal glucose tolerance, but not in diabetes and pre-diabetes.

Adiponectin is better predictor of subclinical atherosclerosis than liver function tests in patients with nonalcoholic fatty liver disease

Adiponectin has recently been considered as a possible link between liver dysfunction and atherosclerosis in patients with nonalcoholic fatty liver disease (NAFLD). The present study was designed to evaluate the relation between circulating adiponectin and arterial stiffness parameters, such as pulse wave velocity (PWV) and aortic augmentation index (AI), in patients with hepatic steatosis. The study group consisted of 52 subjects with NAFLD. PWV and AI were performed using SphygmoCor (version 7.1, AtCor Medical, Sydney, Australia). Metabolic parameters, homeostasis model assessment-insulin resistance, and adiponectin levels were determined. Adiponectin was significantly, positively associated with AI (r = 0.467; P < .0001) and with PWV (r = 0.348; P = .011). No association between arterial stiffness parameters and liver function tests was observed. In a multiple linear regression analysis, adiponectin remained a significant predictor of PWV even after controlling for age, gender, and MAP. Serum adiponectin levels were significantly associated with indices of subclinical atherosclerosis, such as PWV and AI in patients with NAFLD. This association was independent of age, gender, and blood pressure level and suggests an active role of adiponectin in the pathophysiology of vascular disease in this particular population group.

Increased selenoprotein p levels in subjects with visceral obesity and nonalcoholic Fatty liver disease

BACKGROUND

Selenoprotein P (SeP) has recently been reported as a novel hepatokine that regulates insulin resistance and systemic energy metabolism in rodents and humans. We explored the associations among SeP, visceral obesity, and nonalcoholic fatty liver disease (NAFLD).

METHODS

We examined serum SeP concentrations in subjects with increased visceral fat area (VFA) or liver fat accumulation measured with computed tomography. Our study subjects included 120 nondiabetic individuals selected from participants of the Korean Sarcopenic Obesity Study. In addition, we evaluated the relationship between SeP and cardiometabolic risk factors, including homeostasis model of insulin resistance (HOMA-IR), high sensitivity C-reactive protein (hsCRP), adiponectin values, and brachial-ankle pulse wave velocity (baPWV).

RESULTS

Subjects with NAFLD showed increased levels of HOMA-IR, hsCRP, VFA, and several components of metabolic syndrome and decreased levels of adiponectin and high density lipoprotein cholesterol than those of controls. Serum SeP levels were positively correlated with VFA, hsCRP, and baPWV and negatively correlated with the liver attenuation index. Not only subjects with visceral obesity but also those with NAFLD exhibited significantly increased SeP levels (P<0.001). In multiple logistic regression analysis, the subjects in the highest SeP tertile showed a higher risk for NAFLD than those in the lowest SeP tertile, even after adjusting for potential confounding factors (odds ratio, 7.48; 95% confidence interval, 1.72 to 32.60; P=0.007).

CONCLUSION

Circulating SeP levels were increased in subjects with NAFLD as well as in those with visceral obesity and may be a novel biomarker for NAFLD.

How adiponectin, leptin, and ghrelin orchestrate together and correlate with the severity of nonalcoholic fatty liver disease

BACKGROUND

Adipose tissue contributes to nonalcoholic fatty liver disease (NAFLD), being a source of fatty acids and cytokines such as leptin and adiponectin, and regulating ghrelin production. Their role in NAFLD pathogenesis remains controversial. We aimed to study the influence of those cytokines on the severity of NAFLD.

METHODS

Morbidly obese individuals with biopsy-proven NAFLD were recruited. The NAFLD activity score was applied to liver histology. Serum concentrations of adiponectin, leptin, and ghrelin were determined.

RESULTS

Eighty-two patients were included, 13% with nonalcoholic steatohepatitis (NASH). Hypertriglyceridemia (P=0.018) and metabolic syndrome (P=0.040) were independent factors associated with NASH. Leptin associated positively and ghrelin associated negatively with BMI; adiponectin associated negatively with the waist to hip ratio. Adiponectin associated negatively with insulin resistance, hypertension, and metabolic syndrome; ghrelin associated positively with diabetes mellitus. Adiponectin below 23 ng/ml associated with NASH (odds ratio 12.95, P<0.001). Leptin increased progressively (P=0.032) and adiponectin decreased (P=0.004) with increasing severity of steatosis. Also, leptin increased progressively with more severe fibrosis (P=0.053). A formula incorporating the three cytokines yielded an AUROC of 0.789 (P=0.002), a sensitivity of 81.8%, and a specificity of 76.1% for NASH.

CONCLUSION

An imbalance in adiponectin, leptin, and ghrelin seems to be associated with more severe NAFLD. A formula combining the three cytokines showed good accuracy for NASH.

Relation between augmentation index and adiponectin during one-year metformin treatment for nonalcoholic steatohepatosis: effects beyond glucose lowering?

Background

Insulin resistance (IR) is the major driving force behind development and progression of atherosclerosis in patients with nonalcoholic fatty liver disease (NAFLD). Therefore, correction of IR is a relevant therapeutic target.

We performed the current trial to evaluate whether 12- month metformin therapy improves vascular stiffness in patients with NAFLD and to assess if this improvement is associated with change in glucose control, insulin resistance or circulating adiponectin.

Methods

In randomized, placebo controlled study, 63 patients with NAFLD were assigned to one of two groups: Group 1 received daily metformin; Group 2 received placebo. Central aortic augmentation index (AI) was performed using SphygmoCor (version 7.1, AtCor Medical, Sydney, Australia) at baseline, at 4-and 12-month treatment period. Metabolic parameters, insulin resistance markers and serum adiponectin levels were determined.

Results

In placebo group: AI did not improve during the treatment period. Liver function and adiponectin levels did not change during the study.

In multiple linear regression analysis, the independent predictors of arterial stiffness improvement were metformin treatment and increase in circulating adiponectin levels.

Among metformin treated patients: AI decreased significantly during the study. ALP and ALT decreased during initial 4-month treatment period, however raised to the pretreatment levels after 12 months. Serum adiponectin level tended to increase during treatment period with metformin.

Conclusions

Metformin treatment was associated with significant decrease in AI during one year treatment in NAFLD patients. These beneficial vascular effects was associated with exposure to metformin per se as well as change in adiponectin levels suggesting that metformin may mediate its vascular effects via glicemic control-independent mechanisms.

Trial registry

no: NCT01084486

Effects of increased systemic inflammation and central obesity on arterial stiffness in patients with nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is associated with increasing arterial stiffness. We studied the effects of inflammation on different measurements of arterial stiffness in NAFLD. We recruited 80 patients with NAFLD and 40 control subjects. Both compliance index (CI) and stiffness index (SI) were measured. Patients with NAFLD had significantly lower CI (3.8 ± 2.1 vs 4.9 ± 2.9 units; P < .05) and higher SI (8.5 ± 2.4 vs 7.1 ± 1.5 m/s; P < .05) than the controls. Patients with NAFLD were further divided into 2 groups according to the median level of high-sensitivity C-reactive protein (hs-CRP). The CI was significantly lower in patients with NAFLD with high hs-CRP than in those with low hs-CRP (3.2 ± 1.7 vs 4.4 ± 2.5 units; P < .05); however, SI was not statistically different. We further found that waist circumference (odds ratio, 1.06; 95% confidence interval, 1.01-1.13; P < .05) was the only independent factor that predicted low CI (<median value) in patients with NAFLD. Central obesity was an important determinant both for increased arterial stiffness and hs-CRP in Patients with NAFLD.

Association of coffee consumption with serum adiponectin, leptin, inflammation and metabolic markers in Japanese workers: a cross-sectional study

Background:

Mechanisms underlying coffee's beneficial actions against cardiovascular disease and glucose metabolism are not well understood. Little information is available regarding association between coffee consumption and adipocytokines.

Objective:

We investigated potential associations between coffee consumption and adiponectin, leptin, markers for subclinical inflammation, glucose metabolism, lipids and liver enzymes. We then investigated whether adipocytokines played a role in the association between coffee consumption and these markers.

Design and subjects:

This is a cross-sectional study comprising 2554 male and 763 female Japanese workers. Potential relations between coffee consumption and adipocytokines or other markers were evaluated using a multiple linear regression model adjusted for confounding factors. We evaluated whether adiponectin and leptin partly explain the associations between coffee consumption and each marker by multiple mediation analysis.

Results:

Coffee consumption showed significant positive associations with adiponectin and total and low-density lipoprotein cholesterol, and inverse associations with leptin, high sensitivity C-reactive protein (hs-CRP), triglycerides and liver enzymes (all P<0.05). An adjustment for adiponectin and leptin significantly attenuated the associations between coffee consumption and hs-CRP or triglycerides, but not for liver enzymes. No associations were observed between coffee consumption and glucose metabolism-related markers.

Conclusion:

Coffee consumption was associated with high adiponectin and low leptin levels. We speculated that adipocytokines mainly explain the associations of coffee consumption with lipids and hs-CRP. Factors other than adipocytokines may explain the association between coffee consumption and liver function.

Relation of adiponectin to glucose tolerance status, adiposity, and cardiovascular risk factor load

Objective. Adiponectin has anti-atherogenic and anti-inflammatory properties. We investigated the influence of adiponectin on glucose tolerance status, adiposity and cardiovascular risk factors (CVRFs). Design and Patients. Study consisted of 107 subjects: 55 with normal glucose tolerance (NGT) and 52 with impaired glucose regulation (IGR) who were divided into two groups: 24 subjects with impaired fasting glucose (IFG Group) and 28 patients with type 2 diabetes mellitus (DM Group). In additional analysis, study participants were divided into two groups, according to CVRFs: low and high risk. Measurements: Patients were evaluated for glucose, HbA1C, insulin, lipids, CRP, HOMA-IR and adiponectin. Measurements. Patients were evaluated for glucose, HbA1C, insulin, lipids, CRP, HOMA-IR and adiponectin. Results. Adiponectin was significantly higher in NGT group than in IFG (P = 0.003) and DM (P = 0.01) groups. Adiponectin was significantly, positively associated with HDL and inversely associated with glucose, HbA1c, ALT, AST, TG, HOMA-IR. Patients with higher CVRFs load have lesser adiponectin compared to patients with low cardiovascular risk P < 0.0001). Adiponectin was inversely associated with the number of risk factors (r = −0.430, P = 0.0001). Conclusions. Circulating adiponectin was significantly lower in subjects with different degree of IGR compared to subjects with normal glucose homeostasis. Adiponectin was significantly lower in high risk group than low risk group and decreased concurrently with increased number of CVRFs.

Treatment with insulin sensitizer metformin improves arterial properties, metabolic parameters, and liver function in patients with nonalcoholic fatty liver disease: a randomized, placebo-controlled trial

Insulin resistance has an important role in the development of nonalcoholic fatty liver disease (NAFLD) and is involved in both pathological processes: hepatic steatosis and atherosclerosis. Therefore, treatment of NAFLD with insulin sensitizers is likely to have a favorable effect toward hepatic steatosis and cardiovascular outcomes. The present study investigated the effect of metformin on arterial properties, metabolic parameters, and liver function in patients with NAFLD. In a randomized, placebo-controlled study, 63 patients with NAFLD were assigned to 1 of 2 groups: Group 1 received daily metformin; group 2 received placebo. Pulse wave velocity (PWV) and augmentation index (AI) were measured using SphygmoCor (version 7.1; AtCor Medical, Sydney, Australia) at baseline and at the end of the 4-month treatment period. Metabolic measures and serum adiponectin levels were determined. Among metformin-treated patients, PWV and AI decreased significantly during the study. Significant declines in fasting glucose, triglyceride, and alkaline phosphatase and a significant increase in high-density lipoprotein cholesterol were observed. Alanine aminotransferase decreased and serum adiponectin increased marginally. In the placebo group, neither PWV nor AI improved significantly during the treatment period. Alanine aminotransferase, aspartate aminotransferase, and adiponectin did not change in the placebo group. Metformin treatment was associated with significant decrease in PWV and AI in NAFLD patients. This beneficial vascular effect was accompanied by an improvement in glucose and lipid metabolism as well as liver enzymes.

Increased arterial stiffness and impaired endothelial function in nonalcoholic Fatty liver disease: a pilot study

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease both in the general and pediatric population and has been associated with increased cardiovascular risk. Arterial function and early atherosclerotic changes are markers of cardiovascular disease and independent predictors of the corresponding risk. Through a global approach, we investigated the relationships between NAFLD and functional arterial changes and early atherosclerosis.

METHODS

A total of 23 consecutive patients (mean age 55 ± 14 years, 11 males) with biopsy evidence of NAFLD and 28 control subjects matched for age, gender, body mass index, and other cardiovascular risk factors participated in the study.

RESULTS

Compared to controls, NAFLD subjects had significantly higher carotid-femoral pulse wave velocity (PWV; 8.2 ± 1.3 m/s vs. 6.9 ± 1.3 m/s, P = 0.001), higher carotid intima-media thickness (IMT; 0.79 ± 0.18 mm vs. 0.67 ± 0.13 mm, P = 0.01), and reduced flow-mediated dilatation (FMD; 1.92 ± 2.11% vs. 4.8 ± 2.43%, P < 0.001). In multivariable analysis, presence of NAFLD was an independent determinant of both PWV and FMD, whereas leptin was an independent determinant of PWV (B = 0.036, P < 0.05), and adiponectin was independently associated with FMD (B = 0.104, P < 0.05). In addition, histological activity of liver disease expressed by the global Brunt Grade was associated independently with FMD (B = -1.054, P < 0.05).

CONCLUSIONS

NAFLD is associated with arterial stiffness and endothelial dysfunction. Given the important independent prognostic role of these arterial indexes, these findings have important implications for increased cardiovascular risk in patients with NAFLD.

Identifying non-alcoholic fatty liver disease among asymptomatic overweight and obese individuals by clinical and biochemical characteristics

OBJECTIVE

To determine the prevalence of liver steatosis among asymptomatic individuals attending an out-patient clinic for a problem of overweight, and to define the discriminatory value of several characteristics for predicting liver steatosis among them.

DESIGN AND PARTICIPANTS

Consecutive patients Swith a body mass index (BMI) of > or =25 kg/m2 who consented to undergo liver ultrasound and blood tests were recruited for inclusion. Receiver operating characteristic (ROC) curves were generated and statistical indices of diagnostic performance and their corresponding 95% confidence intervals (95% CI) were computed. Logistic regression analyses were performed to determine whether a combination of characteristics could improve diagnostic accuracy.

RESULTS

We enrolled sixty-eight subjects (mean BMI, 37.5 kg/m2), of whom 39 (57.4%) had liver steatosis on ultrasound. Logistic regression analyses indicated that only 3 variables were significantly and independently correlated with liver steatosis: female gender, low adiponectin levels, and high insulin resistance index. A composite index for predicting liver steatosis was calculated by summing the risk factors of female gender, low adiponectin, and insulin resistance index (FAIR score). The accuracy of this score was determined by ROC analysis to be 0.85 (95% CI, 0.74-0.96; P < 0.001). The presence of two or more risk factors (FAIR score > or =2) had a sensitivity, specificity, positive predictive value, and negative predictive value of 77%, 91%, 92%, and 74%, respectively. The likelihood ratio for a positive result was 8.43.

CONCLUSIONS

Among asymptomatic overweight individuals attending an out-patient clinic, the prevalence of liver steatosis on ultrasound is 57%. Female gender, the insulin resistance index, and low adiponectin are significant and independent predictors of liver steatosis. A combination of these three factors allows sensitivity and specificity for non alcoholic fatty liver of 77% and 91%, respectively.

Correlates and heritability of nonalcoholic fatty liver disease in a minority cohort

Nonalcoholic fatty liver disease (NAFLD) is associated with obesity and insulin resistance. The condition disproportionately affects Hispanic Americans. The aims of this study were to examine the risk factors and heritability of NAFLD in 795 Hispanic American and 347 African-American adults participating in the Insulin Resistance Atherosclerosis Study (IRAS) Family Study. Computed tomography (CT) scans of the abdomen were evaluated centrally for measures of liver-spleen (LS) density ratio and abdominal fat distribution. Other measures included insulin sensitivity (SI) calculated from a frequently sampled intravenous glucose tolerance test and various laboratory measures. Statistical models which adjust for familial relationships were estimated separately for the two ethnic groups. Heritability was calculated using a variance components approach. The mean age of the cohort was 49 years (range 22-84); 66% were female. NAFLD (LS ratio<1) was more common in Hispanic Americans (24%) than African Americans (10%). NAFLD was independently associated with SI and visceral adipose tissue (VAT) area in both ethnic groups, although the proportion of explained variance was considerably higher in the Hispanic models. Adiponectin contributed significantly in the African-American models whereas triglycerides (TGs) and plasminogen activator inhibitor 1 (PAI-1) contributed only in the Hispanic models. Liver density was modestly heritable in both ethnic groups (h2 approximately 0.35). In summary, the prevalence of NAFLD was twofold greater in Hispanic than African Americans. Certain correlates of NAFLD were similar between the ethnic groups, whereas others were distinct. NAFLD was modestly heritable. These findings suggest that NAFLD may have a differing environmental and/or genetic basis in these ethnic groups.

Nonalcoholic fatty liver disease in asymptomatic Brazilian adolescents

AIM

To evaluate the prevalence and clinical characteristics of Nonalcoholic fatty liver disease (NAFLD) among asymptomatic Brazilian adolescents.

METHODS

Transversal observational study included asymptomatic adolescents with central obesity from private and public schools in Salvador-Bahia, northeastern Brazil. The children answered a questionnaire that included age, gender, race, and medical history, and were submitted to a complete physical exam and abdominal ultrasound. Biochemical exams included: ALT, AST, GGT, C reactive protein (CRP), fasting glucose, insulin, cholesterol and triglycerides. Criteria for NAFLD included: the presence of steatosis in ultrasound and/or high level of ALT, negative or occasional historic of intake of alcohol (<or= 140 g/wk), negative investigation for hepatitis A, B, C, auto-immune hepatitis, Wilson disease and hemochromatosis.

RESULTS

From October, 2005 to October, 2006, the study included 1801 subjects between 11 and 18 years of age and a mean age of 13.7+/-2.0 years. One hundred ninety-nine had central obesity. The prevalence of NAFLD was 2.3%, most of whom were male and white. Insulin resistance (IR) was observed in 22.9% of them and had positive correlations with ALT and GGT (P<0.05). Elevated CRP was observed in 6.9% of the cases; however, it was not associated with WC, IR or liver enzymes.

CONCLUSION

The prevalence of NAFLD in Brazilian adolescents was low. The ethnicity may have influence this frequency in the population studied, which had a large proportion of African descendents.

Association of adiponectin with procollagen type I carboxyterminal propeptide in non-diabetic essential hypertension

OBJECTIVE

The serum concentration of procollagen type I carboxyterminal propeptide (PICP) is a good marker for collagen deposition in hypertension. Increased collagen deposition was associated with myocardial fibrosis and increased arterial stiffness. A decreased adiponectin level is associated with increased atherosclerosis. The role of adiponectin and its relation to PICP in essential hypertension have rarely been studied before.

METHODS

We recruited 188 non-diabetic uncomplicated hypertensive patients (mean age: 41+/-7 years; 128 men). No patient had vascular complications or renal or liver diseases. Overnight fasting blood samples were collected to assess patient lipid profiles, blood sugar, insulin, high-sensitivity C-reactive protein (hsCRP), PICP and adiponectin. Carotid to radial pulse wave velocity (PWV) measured using tonometry was used as an index of arterial stiffness.

RESULTS

Adiponectin (r = -0.216, p = 0.003) and male gender (p<0.001) were independent determinants of PICP. Diastolic blood pressure (r = 0.422, p<0.001) and current smoking (p = 0.005) were independent determinants of PWV. PWV was significantly correlated with PICP (r = 0.156, p = 0.034). Adiponectin was significantly correlated with triglyceride (r = -0.276, p<0.001), high-density lipoprotein (r = 0.262, p<0.001), the homeostasis model assessment (HOMA) index (r = -0.220, p = 0.002), hsCRP (r = -0.207, p = 0.004) and the body mass index (BMI) (r = -0.202, p = 0.005). After compensation with possible confounding factors, adiponectin was still significantly correlated with PICP (beta = -0.196, p = 0.006).

CONCLUSION

Serum adiponectin may be a marker for metabolic syndrome in essential hypertension. Adiponectin was significantly negatively correlated with PICP. Metabolic syndrome probably plays an important role in increased collagen synthesis and arterial stiffness through the effects of decreased adiponectin in non-diabetic essential hypertension.

Association between plasma alkaline phosphatase and C-reactive protein in Hong Kong Chinese

BACKGROUND

Alkaline phosphatase (ALP) is a biomarker for hepatobiliary and skeletal diseases. It is also raised in sepsis. In atherosclerotic plaques, ALP is expressed. Similar to C-reactive protein (CRP), it may be another marker of systemic inflammation. Therefore, we investigated their association in a Hong Kong Chinese population.

METHODS

Plasma ALP and CRP were measured in 205 subjects (110 men, 95 women; age 55.2+/-11.6 years) in the Hong Kong Cardiovascular Risk Factor Prevalence Study-2 cohort.

RESULTS

The blood levels of ALP and CRP were significantly correlated (r=0.30, p<0.001), which was due to a significant correlation in women (r=0.43, p<0.001). In a multivariate model, CRP level was related to ALP (beta=0.18, p=0.008). After adjusting for confounding factors and other liver enzymes, the relationship between ALP and CRP remained significant in women (beta=0.28, p=0.019), but in men, ALP was not an independent determinant of CRP levels.

CONCLUSIONS

ALP may be another marker of systemic inflammation, especially in women. Whether it provides clinical information additional to CRP requires further study.

Serum retinol-binding protein 4 levels are elevated in non-alcoholic fatty liver disease

OBJECTIVE

Retinol-binding protein 4 (RBP4) is a recently identified adipokine that is elevated in the serum in several insulin-resistant states. We investigated the relationship between non-alcoholic fatty liver disease (NAFLD) and serum RBP4 in nondiabetic adults.

METHODS

One hundred and fifty-nine nondiabetic, non-alcoholic subjects (95 males and 64 females) participated in this study. Division of subjects into a NAFLD group (n = 73; 45 males and 28 females) or a normal group (n = 86; 50 males and 36 females) was based on the presence of fatty liver disease determined by sonography.

RESULTS

Serum RBP4 levels in the NAFLD group were significantly higher than those in the normal group (62.8 +/- 16.0 mg/l vs. 51.7 +/- 14.6 mg/l, P < 0.0001). Multiple logistic regression analysis revealed that the RBP4 level was an independent factor associated with NAFLD (P = 0.0042). In addition, serum RBP4 levels were positively correlated with serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyltranspeptidase (GGT) levels. The significant association between serum RBP4 and GGT levels remained even after adjusting for age, gender, body mass index, the homeostasis model of assessment (HOMA) value and the presence of NAFLD (r = 0.3097, P = 0.0002).

CONCLUSION

Serum RBP4 levels are significantly associated with NAFLD and liver enzymes.

Nonalcoholic fatty liver disease and carotid atherosclerosis in children

Nonalcoholic fatty liver disease (NAFLD) is closely associated with several metabolic syndrome features, including obesity, dyslipidemia, insulin resistance, and increased cardiovascular risk. The present study was undertaken to assess whether NAFLD in children is associated with increased carotid artery intima-media thickness (IMT), a marker of early-generalized atherosclerosis. We analyzed carotid IMT along with serum triglycerides, total, low-density lipoprotein and high-density lipoprotein cholesterol, glucose, insulin, insulin resistance index (as homeostasis model assessment of insulin resistance), aminotransferases, leptin, and adiponectin in 29 obese children with NAFLD, 33 obese children without liver involvement, and 30 control children. The diagnosis and severity of NAFLD was based on ultrasound scan, after exclusion of infectious and metabolic disorders. Obese children with NAFLD had significantly increased carotid IMT [mean 0.58 (95% confidence intervals 0.54-0.62 mm)] than obese children without liver involvement [0.49 (0.46-0.52) mm; p = 0.001] and control children [0.40 (0.36-0.43) mm; p < 0.0005]. In a stepwise multiple regression model, after adjusting for age, gender, Tanner stage, and cardiovascular risk factors, the severity of fatty liver was significantly associated with maximum IMT (b = 0.08; p < 0.0005). Our results suggest that NAFLD is strongly associated with carotid atherosclerosis even in childhood.

Total and high molecular weight but not trimeric or hexameric forms of adiponectin correlate with markers of the metabolic syndrome and liver injury in Thai subjects

CONTEXT/OBJECTIVE

Decreased total adiponectin has been associated with metabolic disorders, including obesity, diabetes, fatty liver, and the metabolic syndrome. Although circulating adiponectin is composed of trimers, hexamers, and high molecular weight (HMW) multimers, there has been limited study of the specific metabolic correlates of these isoforms in humans. Thus, our objective was to evaluate the associations of these adiponectin isoforms with metabolic and anthropometric parameters.

DESIGN/PARTICIPANTS/SETTING

A total of 53 diabetic and 68 nondiabetic subjects attending outpatient clinics underwent cross-sectional metabolic characterization. Circulating levels of HMW, hexameric, and trimeric adiponectin were measured using a multimeric adiponectin ELISA based upon selective protease-mediated digestion.

RESULTS

On Spearman univariate analysis, both total and HMW adiponectin levels were inversely associated with body mass index, fasting glucose, homeostasis model of assessment of insulin resistance, triglycerides, and alanine aminotransferase (ALT) (all |r| >or= 0.22; P < 0.05), with the HMW isoform also positively correlated with high-density lipoprotein cholesterol (r = 0.19; P = 0.036). In contrast, hexameric and trimeric adiponectin were significantly associated with only body mass index (r = -0.23; P = 0.0102) and mid-upper arm circumference (r = 0.21; P = 0.039), respectively. On separate forward stepwise multiple linear regression analyses, fasting glucose and ALT emerged as independent, negative covariates of both total and HMW adiponectin, whereas no independent covariates of hexameric and trimeric adiponectin were identified. Furthermore, after adjustment for age, gender, and diabetes, mean ALT was highest in subjects in the lowest tertile of HMW adiponectin, followed in turn by the middle and highest tertiles, respectively (trend P = 0.028).

CONCLUSIONS

HMW adiponectin, but not hexameric or trimeric, tracks with the metabolic correlates of total adiponectin. Furthermore, an independent inverse association exists between ALT and HMW adiponectin.

Prevalence of non-alcoholic fatty liver and characteristics in overweight adolescents in the general population

Overweight and obesity among children and adolescents are increasing. Fatty liver disease (FLD) is an emerging problem in this age group. We investigated prevalence of overweight and non-invasive FLD and associated clinical characteristics in a representative population-based sample of 378 children and adolescents aged 12-20 years who were randomly selected from the general population in Leutkirch, Southern Germany. Overweight was defined as having a body mass index above the 90th percentile for the respective age and sex. About 15% of female (29 out of 194) and 12% of male participants (22/182) were overweight. Among females, only one non-overweight individual showed signs of FLD but in more than one third of the overweight males (8/22) signs of FLD were present. Overweight subjects in general had an unfavourable lipid profile and abnormal concentrations of obesity-related hormones such as significantly lower concentrations of adiponectin and increased levels of inflammatory markers including C-reactive protein and fibrinogen. Overweight males with signs of FLD showed even more severe altered metabolic responses compared to those who were overweight without signs of liver injury. FLD was not explained by alcohol consumption or other chronic liver disease. In this sample of children and adolescents representative of the general population a high prevalence of non-alcoholic fatty liver disease (NAFLD) is found in overweight males. These individuals showed the most severe metabolic alterations compared to non-overweight and overweight individuals without NAFLD indicating even higher risk for future overweight and obesity-related diseases such as type 2 diabetes and cardiovascular disease.

Non-alcoholic fatty liver disease, the metabolic syndrome and the risk of cardiovascular disease: the plot thickens

Non-alcoholic fatty liver disease (NAFLD) affects a substantial proportion of the general population and is frequently associated with many features of the metabolic syndrome (MetS). Currently, the importance of NAFLD and its relationship with the MetS is being increasingly recognized, and this has stimulated an interest in the possible role of NAFLD in the development of atherosclerosis. Recent studies have reported the association of NAFLD with multiple classical and non-classical risk factors for cardiovascular disease (CVD). Moreover, there is a strong association between the severity of liver histopathology in NAFLD patients and greater carotid artery intima-media thickness and plaque, and lower endothelial flow-mediated vasodilation (as markers of subclinical atherosclerosis) independent of obesity and other MetS components. Finally, it has recently been demonstrated that NAFLD is associated with an increased risk of all-cause death and predicts future CVD events independently of other prognostic factors, including MetS components. Overall, therefore, the evidence from these recent studies strongly emphasizes the importance of assessing the global CVD risk in patients with NAFLD. Moreover, these novel findings suggest a more complex picture and raise the possibility that NAFLD, as a component of the MetS, might not only be a marker but also an early mediator of CVD.

Associations between plasma adiponectin concentrations and liver histology in patients with nonalcoholic fatty liver disease

OBJECTIVES

To explore associations between plasma adiponectin concentrations and liver histology in patients with nonalcoholic fatty liver disease (NAFLD).

DESIGN AND PATIENTS

In a cross-sectional study, we enrolled 60 consecutive NAFLD patients and 60 age-, sex- and body mass index (BMI)-matched healthy controls.

MEASUREMENTS

NAFLD (by liver biopsy), plasma adiponectin concentrations, insulin resistance (by homeostasis model assessment, HOMA-IR) and metabolic syndrome (MetS) features.

RESULTS

NAFLD patients had a marked decrease in plasma adiponectin concentration (6.1 +/- 2.8 vs. 13.6 +/- 3.8 microg/ml, P < 0.001) compared with matched controls. MetS, as defined by the Adult Treatment Panel III (ATP III) criteria, and its individual components were more frequent among NAFLD patients. The marked differences in adiponectin concentrations that were observed between the groups were little affected by adjustment for age, sex, BMI, HOMA-IR score and MetS components. Notably, decreased adiponectin levels were closely associated with the degree of hepatic steatosis, necroinflammation and fibrosis (P < 0.001 for all) among NAFLD patients. By logistic regression analysis, low adiponectin levels independently predicted hepatic steatosis [odds ratio (OR) 2.3, 95% confidence interval (CI) 1.5-5.8, P < 0.001] and necroinflammation (OR 3.1, 95% CI 1.9-7, P < 0.001), but not fibrosis (P = 0.07), after adjustment for age, sex, BMI, HOMA-IR and MetS components.

CONCLUSIONS

NAFLD patients have markedly lower plasma adiponectin concentrations than control subjects. Low adiponectin levels are strongly associated with the severity of liver histology, thus further supporting the hypothesis that adiponectin might be involved in the development of NAFLD.

Efficacy of rosiglitazone in treatment of nonalcoholic fatty liver disease and its relations with adiponectin

AIM: To explore an effective, safe and convenient method in the treatment of nonalcoholic fatty liver disease (NAFLD) and a marker in the pre-diction of the efficacy.

METHODS: One hundred and twenty-four patients diagnosed with NAFLD (except cirrhosis) were randomly divided into rosiglitazone (RSG) treatment group and placebo group (controls). After treatment with the corresponding methods, comparative analysis on the efficacy and serum adiponectin was performed between the two groups.

RESULTS: ESG significantly improved the liver function, levels of blood glucose, lipid and serum adiponectin, as well as insulin resistance (HOMA-IR) (P < 0.05). The total effective rates were markedly significantly between RSG group and placebo group (57/63 vs 37/61, P < 0.01). The levels of serum alanine aminotransferase (ALT) was significantly correlated with adiponectin level (r = -0.685, P < 0.01) and HOMA-IR (r = 0.447, P < 0.01). The safety was not notably different between the two groups (P > 0.05).

CONCLUSION: RSG is effective and safe in the treatment of NAFLD and serum adiponectin level can be used to predict its efficacy.