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Background: Coronary artery calcium (CAC) improves cardiovascular event prediction. Visceral adipose tissue (VAT) is a cardiometabolic risk factor that may directly or through its related comorbidities determine the obesity-related risk. A clinical VAT estimator could allow an efficient evaluation of obesity-related risk. We aimed to analyze the effect of VAT and its related cardiometabolic risk factors on CAC progression. Methods: CAC was quantified at baseline and after 5 years by computed tomography (CT), determining its progression. VAT and pericardial fat were measured by CT and estimated by a clinical surrogate (METS-VF). Considered cardiometabolic risk factors were: peripheral insulin resistance (IR), HOMA-IR, adipose tissue IR (ADIPO-IR), and adiponectin. Factors independently associated to CAC progression were analyzed by adjusted Cox proportional hazard models, including statin use and ASCVD risk score as covariates. We performed interaction and mediation models to propose possible pathways for CAC progression. Results: The study included 862 adults (53 ± 9 years, 53% women), incidence CAC progression rate: 30.2 (95% CI 25.3–35.8)/1000 person-years. VAT (HR: 1.004, 95% CI 1.001–1.007, p < 0.01) and METS-VF (HR: 1.001, 95% CI 1.0–1.001, p < 0.05) independently predicted CAC progression. VAT-associated CAC progression risk was evident among low-risk ASCVD subjects, and attenuated among medium–high-risk subjects, suggesting that traditional risk factors overcome adiposity in the latter. VAT mediates 51.8% (95% CI 44.5–58.8%) of the effect attributable to IR together with adipose tissue dysfunction on CAC progression. Conclusions: This study supports the hypothesis that VAT is a mediator of the risk conferred by subcutaneous adipose tissue dysfunction. METS-VF is an efficient clinical surrogate that could facilitate the identification of at-risk adiposity subjects in daily clinical practice. [ABSTRACT FROM AUTHOR]

Background: Non-alcoholic fatty liver disease (NAFLD) is a public health problem lacking an approved pharmacological treatment. Omega-3 fatty acids have shown to reverse NAFLD. Chia is a seed rich in α-linolenic acid (ALA), antioxidants, and fiber; therefore, it could be useful to treat NAFLD. Methods: In a single arm experimental design study, the effect of 25 g/day of milled chia was assessed in 25 patients with NAFLD. After two weeks of dietary stabilization (basal condition) and eight weeks of a chia-supplemented isocaloric diet, liver:spleen attenuation index and visceral abdominal fat (VAF) were measured by computed tomography. Lipids, lipoproteins, free fatty acids (FFA), and ALA plasma concentrations were also determined. Results: Dietary chia supplementation induced an increase in plasma ALA concentration (75%) and dietary fiber (55%) consumption. After chia supplementation, VAF (9%), body weight (1.4%), total cholesterol (2.5%), non-high density lipoprotein cholesterol (3.2%), and circulating FFA (8%) decreased. Furthermore, NAFLD regressed in 52% of the treated patients (P < 0.05 for all). Conclusions: The results of the present study show that 25 g/day of milled chia ameliorates NAFLD. Chia is an accessible vegetal source of omega-3 fatty acids, antioxidants, and fiber, which could have the potential to prevent metabolic abnormalities in NAFLD patients. Considering that there is no pharmacological treatment approved for NAFLD, the findings of the present study suggest that a chia-supplemented diet could be an innovative alternative to control this disease. Retrospectively registered: https://clinicaltrials.gov/show/NCT03942822 [ABSTRACT FROM AUTHOR]

Background: Previous studies showed that metabolic syndrome is associated with aortic valve calcification (AVC) and poor outcomes in aortic stenosis (AS). However, if these associations change and how body fat impacts the prognosis of patients in late stage of the disease have been not yet explored. Aims: To determine the association of body mass index (BMI) and visceral fat with AVC and mortality after transcatheter aortic valve replacement (TAVR). Methods: This was a prospective cohort of 170 severe AS patients referred to TAVR. We quantified AVC mass score and fat depots including epicardial adipose tissue, intrathoracic fat, and abdominal visceral (VAF) and subcutaneous fats by computed tomography. Fat depots were indexed to body surface area. All-cause and cardiovascular-related deaths after TAVR were recorded over a median follow-up of 1.2 years. Results: Higher AVC mass was independently associated with low BMI and low VAF. All-cause mortality risk increased with the decrease of BMI and increment of VAF. A stratified analysis by obesity showed that in non-obese, VAF was inversely associated with mortality, whereas in obese, high VAF was associated with higher mortality (p value for interaction < 0.05). At long-term, hazard ratio [HR] with non-obese/low VAF was 2.3 (95% confidence interval [CI] 1.1-4.9; p = 0.021) and HR with obese/high VAF was 2.5 (95% CI 1.1-5.8; p = 0.031) compared with obese/low VAF patients. Conclusions: In AS patients submitted to TAVR, BMI and VAF were inversely associated with AVC. Pre-intervention assessment of VAF by computed tomography may provide a better discrimination of mortality than BMI alone. [ABSTRACT FROM AUTHOR]

Background: Biomarkers for cardiometabolic risk (CMR) factors would be important tools to maximize the effectiveness of dietary interventions to prevent cardiovascular diseases. Thus, the aim of this work was to analyze stearoyl-CoA desaturase (SCD) indexes and n-6/n-3 fatty acids (FA) ratio as biomarkers of CMR induced by feeding rabbits on high fat diets (HFDs). Methods: Rabbits were fed either regular diet or 18 % fat in regular diet (HFD) or 1 % cholesterol diet (HD) or diet containing 1 % cholesterol and 18 % fat (HFD-HD) during 6 weeks. Body weights (BW), blood pressure, visceral abdominal fat (VAF) and glucose tolerance test were determined. Total cholesterol (TC), low density lipoprotein-cholesterol (LDL-C), high density lipoprotein-cholesterol (HDL-C), triglycerides (TG), fasting glucose (FG), and FA levels from plasma were measured. SCD indexes were calculated as product/precursor ratios of individual FA. Results: BW was similar in all diet groups. HD increased TC, LDL-C, HDL-C, and TG. HFD increased TG, VAF and FG, and decreased HDL-C. The addition of HFD to HD joined to dyslipidemia increased VAF and FG. SCD indexes were increased and n-6/n-3 was unchanged in HD. SCD indexes were reduced and n-6/n-3 FA ratio was increased in HFD and HFD-HD. CMR factors were correlated positively with n-6/n-3 FA ratio. Although VAF had a stronger correlation with n-6/n-3 FA ratio than with SCD indexes, VAF was associated independently to both markers. Conclusions: HFD simulating lipid composition of the average Western-style diet induced experimental rabbit models of normal-weight metabolic syndrome (MS). SCD indexes and n-6/n-3 were modified according to the type of dietary fat. Considering that VAF and CMR factors appear to be stronger associated to n-6/n-3 FA ratio than to SCD indexes, n-6/n-3 FA ratio may be a better biomarker of MS and CMR in normal-weight subjects than SCD indexes. [ABSTRACT FROM AUTHOR]

Background: High serum Retinol Binding Protein 4 (RBP4) levels were associated with insulin-resistant states in humans. To determine which fat compartments are associated with elevated RBP4 levels in humans, we measured serum RBP4 and hepatic fat content (HFC), visceral (VFA) and subcutaneous abdominal fat area (SFA) in 106 subjects with non-alcoholic fatty liver disease (NAFLD) without known diabetes. Methods: 106 patients with NAFLD (M/F: 61/45, aged 47.44 ± 14.16 years) were enrolled. Subjects with known diabetes, chronic virus hepatitis, and those with alcohol consumption ≥30 g/d in man and ≥20 g/d in woman were excluded. Anthropometrics and laboratory tests, including lipid profile, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and γ-glutamyltransferase (γ-GT) were conducted. HFC, VFA and SFA were determined by CT scan. Serum RBP4 was detected by an enzyme immunoassay kit and validated by quantitative Western blotting. Results: Circulating RBP4 was negatively associated with high-density lipoprotein cholesterol (HDL-c) (r = -0.392, p < 0.001), but positively with waist-to-hip ratio (WHR) (r = 0.343, p = 0.001), triglyceride (r = 0.330, p = 0.002), VFA (r = 0.298, p = 0.027), systolic blood pressure (r = 0.247, p = 0.020), diastolic blood pressure (r = 0.241, p = 0.023), γ-GT (r = 0.239, p = 0.034), waist circumference (r = 0.218, p = 0.040). Differently, serum RBP4 levels were not associated with HFC (r = 0.199, p = 0.071), SFA, age, BMI, total cholesterol, low-density lipoprotein cholesterol (LDL-c), ALT or AST (all p > 0.05). Multiple linear regression analysis revealed that RBP4 correlated independently with VFA (Standard β = 0.357, p = 0.019) and HDL-c (Standard β = -0.345, p = 0.023) in all subjects, HDL-c (Standard β = -0.315, p = 0.040) in men, VFA/SFA in women (Standard β = 0.471, p = 0.049), not with HFC. However, serum RBP4 was positively correlated with HFC when HFC below 6.34% (r = 0.574, p = 0.001). Conclusions: RBP4 could be a marker of abdominal obesity, however, the role of RBP4 in the pathogenesis of NAFLD is not sufficiently elucidated. [ABSTRACT FROM AUTHOR]

Objectives: This study investigated the effect of bariatric surgery (BS)–induced weight loss on cardiac ectopic fat using 3T magnetic resonance imaging in morbid obesity. Background: Heart disease is one of the leading causes of mortality and morbidity in obese patients. Deposition of cardiac ectopic fat has been related to increased heart risk. Whether sustained weight loss can modulate epicardial fat or myocardial fat is unknown. Methods: Twenty-three morbidly obese patients underwent 1H-magnetic resonance spectroscopy to determine myocardial triglyceride content (MTGC), magnetic resonance imaging to assess epicardial fat volume (EFV), cardiac function, and computed tomography visceral abdominal fat (VAF) measurements at baseline and 6 months after BS. Results: The BS reduced body mass index significantly, from 43.1 ± 4.5 kg/m2 to 32.3 ± 4.0 kg/m2, subcutaneous fat from 649 ± 162 cm2 to 442 ± 127 cm2, VAF from 190 ± 83 cm2 to 107 ± 44 cm2, and EFV from 137 ± 37 ml to 98 ± 25 ml (all p < 0.0001). There was no significant change in MTGC: 1.03 ± 0.2% versus 1.1 ± 0.2% (p = 0.85). A significant reduction in left ventricular mass (118 ± 24 g vs. 101 ± 18 g) and cardiac output (7.1 ± 1.6 l/min vs. 5.4 ± 1.0 l/min) was observed and was statistically associated with weight loss (p < 0.05). The loss in EFV was limited (−27 ± 11%) compared to VAF diminution (−40 ± 19%). The EFV variation was not correlated with percentage of body mass index or VAF loss (p = 0.007). The ratio of %EFV to %VAF loss decreased with sleep apnea syndrome (1.34 ± 0.3 vs. 0.52 ± 0.08, p < 0.05). Conclusions: Six-month BS modulates differently cardiac ectopic fat deposition, with a significant decrease in epicardial fat and no change in myocardial fat. Epicardial fat volume loss was limited in patients with sleep apnea. (Impact of Bariatric Surgery on Epicardial Adipose Tissue and on Myocardial Function; NCT01284816) [Copyright &y& Elsevier]

Abstract: Background: Excess visceral abdominal tissue (VAT) is more strongly associated with risk factors of coronary artery disease (CAD) than body mass index (BMI) or waist circumference. However, whether adding VAT measurements to CAD risk factors provides better risk assessment for CAD progression has not been fully evaluated. Methods and results: This prospective cohort study comprised 553 CAD patients with coronary plaque with ≤50% coronary stenosis as assessed by computed tomography (CT) angiography. Quantification of VAT area was performed together with CT angiography using abdominal CT scanning. After a mean 38±8months follow-up, 320 patients underwent repeated CT scans for worsening angina symptoms without findings of positive ischemia. Increased segments of noncalcified plaque were seen in 152 (48%) and an increased calcium score was seen in 261 (82%) patients. The risk for progression of noncalcified plaque increased steadily with higher VAT quartiles, independent of CAD risk factors. Patients in the higher quartiles were at increased risk of progression of noncalcified plaque (quartiles IV OR 4.7; 95% CI 2.3–9.4, p-value<0.001). In contrast, increases above the median calcium score showed no independent correlation to VAT. Compared to VAT, progression of noncalcified plaque showed no phased increase with higher waist circumference and weaker increase with higher BMI quartiles. Conclusion: VAT accumulation was positively associated with progression of coronary noncalcified plaque, but not of calcified plaque. This suggests that risk assessment of progression of noncalcified plaque can be improved by combining VAT measurements and CAD risk factors. [Copyright &y& Elsevier]

Objectives:It is generally agreed that excess abdominal fat, in particular visceral abdominal fat (VAF), is related to an increased risk for obesity-related complications. We examined the association between metabolic risk factors and maintaining VAF after weight loss intervention.Methods:A total of 54 postmenopausal, obese women who achieved a VAF loss of at least 10% from their baseline values during a 14-week intervention were enrolled as subjects. Body weight, VAF assessed by CT scans, and metabolic risk factors (that is, blood pressure, lipids and glucose) were measured at baseline (week 0), post-intervention (week 15), and at a 2-year follow-up (week 105). The subjects were divided into two groups according to their changes in VAF between weeks 15 and 105 (follow-up period): (1) VAF gainers (VAF changes >0 cm2, n=28) or (2) VAF maintainers (VAF changes 0 cm2, n=26).Results:The mean change in VAF of all subjects during the 14-week intervention was −34±16 cm2 (−29.7±12.3%) (P<0.01). Along with this change, improvements (P<0.05) were observed in all metabolic risk factors except for high-density lipoprotein cholesterol (HDLC). During the follow-up period, there were interactions between the two VAF groups in HDLC, triglycerides (TG) and total cholesterol (TC)/HDLC ratio (all P<0.01). In particular, the HDLC of VAF maintainers improved, and the value at week 105 exceeded baseline level (P<0.01). However, systolic and diastolic blood pressure, TC and low-density lipoprotein cholesterol in the VAF maintainers increased (all P<0.05) back to their mean baseline level despite a further decrease in their VAF during the follow-up period (P<0.01).Conclusions:This study shows that long-term maintenance of VAF after weight loss intervention is associated with improvements in HDLC and TG among obese, postmenopausal women. [ABSTRACT FROM AUTHOR]

To assess whether there is any clinical significance for determining the normal range of subcutaneous abdominal fat area, we compared fat area with insulin sensitivity. Visceral and subcutaneous abdominal fat area the L4-L5 thoracic level was determined by computed tomography (CT). Plasma glucose and insulin levels were determined after an overnight fast and calculated by the homeostatic model assessment of insulin resistance (HOMA-IR). We analyzed 350 (180 male and 170 female) subjects whose BMI was 18.5≤BMI<25. The subcutaneous abdominal fat area of the female subjects was 124.7 ± 46.13 cm2 and that of male subjects was 77.53 ± 37.53 cm2 (mean ± SD). We compared HOMA-IR between subjects whose visceral abdominal fat area was above 100 cm2 and subcutaneous abdominal fat area below the mean + 2SD (15 subjects, 6 male and 9 female) with subjects whose visceral abdominal fat area was also above 100 cm2 but whose subcutaneous abdominal fat area was above the mean + 2SD (20 subjects, 7 male and 13 female). The HOMA-IR of the former subjects group was 8.17+/−6.22 and that of the latter subjects group was 3.37+/−2.07 (p = 0.0486). Subjects with increased subcutaneous abdominal fat area displayed lower HOMA-IR values, demonstrating a protective effect of subcutaneous fat for individuals with visceral fat area above 1002 cm. [ABSTRACT FROM AUTHOR]