Effects of diet and physical activity on adiposity and body fat distribution: implications for the prevention of cardiovascular disease

Evaluation of visceral adipose tissue thresholds for elevated metabolic syndrome risk across diverse populations: A systematic review

Beyond obesity, excess levels of visceral adipose tissue (VAT) significantly contribute to the risk of developing metabolic syndrome (MetS), although thresholds for increased risk vary based on population, regions of interest, and units of measure employed. We sought to determine whether a common threshold exists that is indicative of heightened MetS risk across all populations, accounting for sex, age, BMI, and race/ethnicity. A systematic literature review was conducted in September 2023, presenting threshold values for elevated MetS risk. Standardization equations harmonized the results from DXA, CT, and MRI systems to facilitate a comparison of threshold variations across studies. A total of 52 papers were identified. No single threshold could accurately indicate elevated risk for both males and females across varying BMI, race/ethnicity, and age groups. Thresholds fluctuated from 70 to 165.9 cm2, with reported values consistently lower in females. Generally, premenopausal females and younger adults manifested elevated risks at lower VAT compared to their older counterparts. Notably, Asian populations exhibited elevated risks at lower VAT areas (70-136 cm2) compared to Caucasian populations (85.6-165.9 cm2). All considered studies reported associations of VAT without accommodating covariates. No single VAT area threshold for elevated MetS risk was discernible post-harmonization by technology, units of measure, and region of interest. This review summarizes available evidence for MetS risk assessment in clinical practice. Further exploration of demographic-specific interactions between VAT area and other risk factors is imperative to comprehensively delineate overarching MetS risk.

Is Metabolic Score for Visceral Fat (METS-VF) a Better Index Than Other Adiposity Indices for the Prediction of Visceral Adiposity

Background

Visceral adiposity is an important risk factor for cardiometabolic diseases.

Objective

To determine whether the Metabolic Score for Visceral Fat (METS-VF) is more effective than other adiposity indices in predicting visceral fat area (VFA).

Methods

In this single-center and cross-sectional study, we included patients aged 20-50 years, without diabetes and coronary artery disease, who underwent computed tomography (CT) including the third lumbar vertebra. Age, blood pressure, waist circumference (WC), hip circumference, fasting lipids, and glucose were assessed. VFA was measured by cross-sectional examination of CT. The correlation of WC, body mass index (BMI), waist-hip ratio (WHR), lipid accumulation product (LAP), visceral adiposity index (VAI), a body shape index (ABSI), body roundness index (BRI), and METS-VF with VFA was analyzed by correlation analysis. The cut-off values and area under the curve (AUC) for identifying increased VFA (>130 cm2) were determined.

Results

We included 185 individuals with mean age 38.2 ± 8 and female predominance (58.4%). There was a significant positive correlation between all indices and VFA (p<0.001). ROC analysis revealed that METS-VF and WC demonstrated the highest predictive value for identifying increased VFA. In both men (p=0.001) and women (p<0.001), METS-VF (AUC 0.922 and 0.939, respectively) showed a significant superiority over ABSI (AUC 0.702 and 0.658, respectively), and VAI (AUC 0.731 and 0.725, respectively). Additionally, in women, its superiority over WHR (AUC 0.807) was also statistically significant (p=0.003). We identified a METS-VF cut-off point >6.4 in males >6.5 in females and WC cut-off point >88 cm in males (AUC 0.922), >90.5 cm in females (AUC 0.938).

Conclusion

METS-VF is strongly associated with visceral adiposity and better to predict increased VFA. However, its superiority over WC, BMI, BRI, and LAP was not significant. The results emphasize that WC is more appealing as screening indicator for visceral adiposity considering its easy use.

Clinical Trial Registry Name

Clinicaltrials.gov (http://www.clinicaltrials.gov).

Clinical Trial Registry Url

https://clinicaltrials.gov/ct2/show/NCT05648409.

Clinical Trial Registry Number

NCT05648409.

Body composition parameters correlate with the endoscopic severity in Crohn's disease patients treated with infliximab

Background

The disease activity status and behavior of Crohn's disease (CD) can reflect the severity of the disease, and changes in body composition are common in CD patients.

Aims

The aim of this study was to investigate the relationship between body composition parameters and disease severity in CD patients treated with infliximab (IFX).

Methods

Patients with CD assessed with the simple endoscopic score (SES-CD) and were treated with IFX were retrospectively collected, and body composition parameters at the level of the 3rd lumbar vertebrae were calculated from computed tomography (CT) scans of the patients. The correlation of patients' body composition parameters with disease activity status and disease behavior was analyzed, and the diagnostic value of the relevant parameters was assessed using receiver operating characteristic (ROC) curves.

Results

A total of 106 patients were included in this study. There were significant differences in the subcutaneous adiposity index (SAI) (p = 0.010), the visceral adiposity index (VAI) (p < 0.001), the skeletal muscle mass index (SMI) (p < 0.001), and decreased skeletal muscle mass (p < 0.001) among patients with different activity status. After Spearman and multivariate regression analysis, SAI (p = 0.006 and p = 0.001), VAI (p < 0.001 and p < 0.001), and SMI (p < 0.001and p = 0.007) were identified as independent correlates of disease activity status (both disease activity and moderate-to-severe activity), with disease activity status independently positively correlated with SAI and SMI and independently negatively correlated with VAI. In determining the disease activity and moderate-to-severe activity status, SMI performed best relative to SAI and VAI, with areas under the ROC curve of 0.865 and 0.801, respectively. SAI (p = 0.015), SMI (p = 0.011) and decreased skeletal muscle mass (p = 0.027) were significantly different between different disease behavior groups (inflammatory disease behavior group, complex disease behavior group) but were not independent correlates (p > 0.05).

Conclusion

Body composition parameters of CD patients treated with IFX correlate with the endoscopic disease severity, and SMI can be used as a reliable indicator of disease activity status.

Association of Hypovitaminosis D with Sleep Parameters in Rotating Shift Worker Drivers

Objective  To evaluate the association between sleep parameters and hypovitaminosis D in rotating shift drivers. Material and Methods  We conducted a cross-sectional study on 82 male rotating shift workers (24-57 years old) with at least one cardiovascular risk factor (such as hyperglycemia, dyslipidemia, abdominal obesity, physical inactivity, hypertension, and smoking). Polysomnography was used to evaluate sleep parameters. Logistic regression was used to model the association between hypovitaminosis D and sleep parameters after adjustment for relevant covariates. Results  Hypovitaminosis D (< 20 ng/mL) was seen in 30.5% of the workers. Shift workers with hypovitaminosis D had lower sleep efficiency (odds ratio [OR]: 3.68; 95% confidence interval [CI]: 1.95-5.53), lower arterial oxygen saturation (OR: 5.35; 95% CI: 3.37-6.12), and increased microarousal index (OR: 3.85; 95% CI: 1.26-5.63) after adjusting. Conclusion  We suggest that hypovitaminosis D is associated with greater sleep disturbances in rotating shift workers.

Distance to Natural Environments, Physical Activity, Sleep, and Body Composition in Women: An Exploratory Analysis

A growing body of evidence indicates that living close to nature is associated with better health and well-being. However, the literature still lacks studies analyzing the benefits of this proximity for sleep and obesity, particularly in women. The purpose of this study was to explore how distance to natural spaces is reflected in women's physical activity, sleep, and adiposity levels. The sample consisted of 111 adult women (37.78 ± 14.70). Accessibility to green and blue spaces was assessed using a geographic-information-system-based method. Physical activity and sleep parameters were measured using ActiGraph accelerometers (wGT3X-BT), and body composition was assessed using octopolar bioimpedance (InBody 720). Nonlinear canonical correlation analysis was used to analyze the data. Our findings reveal that women living in green spaces close to their homes had lower levels of obesity and intra-abdominal adiposity. We also demonstrated that a shorter distance to green spaces seemed to correlate with better sleep onset latency. However, no relationship was found between physical activity and sleep duration. In relation to blue spaces, the distance to these environments was not related to any health indicator analyzed in this study.

Characterization and prevalence of obesity among normal weight college students

Normal weight obesity (NWO) describes individuals who have a normal weight body mass index (BMI), but have an unhealthy amount of body fat. Based on the life-long habits that develop during college, exploring NWO among a college-aged population may be essential in identifying and preventing obesity that develops in early adulthood. This study aimed to characterize NWO among young adults with normal weight BMI. 94 college students (Mean ± SD: Age: 19.6 ± 1.5 yrs; BMI: 21.9 ± 1.8 kg/m²) enrolled during the Fall semester (Aug-Oct) were assessed for body composition by dual energy X-ray absorptiometry to determine body fat percentage, fat mass, lean mass and trunk fat; lifestyle habits were characterized from validated questionnaires. Mean arterial pressure and metabolic biomarkers [total cholesterol, high density lipoproteins, non-high density lipoproteins, and glucose] were evaluated for cardiometabolic health. NWO was defined using data from the National Health and Nutrition Examination Survey (NHANES) for body fat percentage. Data was analyzed by group (NWO vs NWL) and sex. with independent t-tests to investigate continuous data, and chi-square test of independence for categorical data. Rates of NWO for the total sample were 13.8%. Males (n=30) had a higher rate of NWO (26.7%) compared to females (n=64; 7.8%). NWO individuals had higher fat mass (p=0.024), trunk fat (p<0.001), and larger waist to hip ratio (p<0.001) than normal weight lean. NWO also engaged in less vigorous physical activity (p=0.043). The occurrence of NWO among otherwise healthy college students is evident. Identification of these individuals may be an effective component for obesity prevention and treatment. Determining feasible methods to measure body fat in this population is essential, as BMI may mask obesity in a young adult population.

Sex-specific associations of fat mass and muscle mass with cardiovascular disease risk factors in adults with type 2 diabetes living with overweight and obesity: secondary analysis of the Look AHEAD trial

Background

Distinguishable sex differences exist in fat mass and muscle mass. High fat mass and low muscle mass are independently associated with cardiovascular disease (CVD) risk factors in people living with type 2 diabetes; however, it is unknown if the association between fat mass and CVD risk is modified by muscle mass, or vice versa. This study examined the sex-specific interplay between fat mass and muscle mass on CVD risk factors in adults with type 2 diabetes living with overweight and obesity.

Methods

Dual-energy X-ray absorptiometry (DXA) measures were used to compute fat mass index (FMI) and appendicular muscle mass index (ASMI), and participants were separated into high-fat mass vs. low-fat mass and high-muscle mass vs. low-muscle mass. A two-way analysis of covariance (ANCOVA: high-FMI vs. low-FMI by high-ASMI vs. low-ASMI) was performed on CVD risk factors (i.e., hemoglobin A1C [A1C]; high-density lipoprotein cholesterol; low-density lipoprotein cholesterol; triglycerides; systolic and diastolic blood pressure; cardiorespiratory fitness, depression and health related-quality of life [HR-QoL]) at baseline and following a 1-year intensive lifestyle intervention (ILI) for females and males separately, with a primary focus on the fat mass by muscle mass interaction effects.

Results

Data from 1,369 participants (62.7% females) who completed baseline DXA were analyzed. In females, there was a fat mass by muscle mass interaction effect on A1C (p = 0.016) at baseline. Post-hoc analysis showed that, in the low-FMI group, A1C was significantly higher in low-ASMI when compared to high-ASMI (60.3 ± 14.1 vs. 55.5 ± 13.5 mmol/mol, p = 0.023). In the high-FMI group, there was no difference between high-ASMI and low-ASMI (56.4 ± 12.5 vs. 56.5 ± 12.8 mmol/mol, p = 0.610). In males, only high-FMI was associated with higher A1C when compared to low-FMI (57.1 ± 14.4 vs. 54.2 ± 12.0 mmol/mol, p = 0.008) at baseline. Following ILI, there were significant fat mass by muscle mass interaction effects on changes in the mental component of HR-QoL in males.

Conclusion

Considering that A1C predicts future CVD, strategies to lower A1C may be especially important in females with low fat and low muscle mass living with type 2 diabetes. Our results highlight the complicated and sex-specific contribution of fat mass and muscle mass to CVD risk factors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01468-x.

Visceral Adiposity, Inflammation, and Testosterone Predict Skeletal Muscle Mitochondrial Mass and Activity in Chronic Spinal Cord Injury

Background

Mitochondrial health is an important predictor of several health-related comorbidities including obesity, type 2 diabetes mellitus, and cardiovascular disease. In persons with spinal cord injury (SCI), mitochondrial health has been linked to several important body composition and metabolic parameters. However, the complex interplay of how mitochondrial health is affected has yet to be determined in this population.

Objective

In this study, we examined the contribution of visceral adiposity, inflammatory biomarkers, testosterone and circulating serum growth factors as predictors of mitochondrial health in persons with chronic SCI.

Participants

Thirty-three individuals with chronic SCI (n = 27 Males, n = 6 Females, age: 40 ± 13.26 years, level of injury: C4-L1, BMI: 23 ± 5.57) participated in this cross-sectional study.

Methods

Visceral adipose tissue (VAT) was measured via magnetic resonance imaging (MRI). After an overnight fast, serum testosterone, inflammatory biomarkers [interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), c-reactive protein (CRP)], and anabolic growth factors [insulin-like growth factor 1 (IGF-1), insulin-like growth factor binding protein 3 (IGFBP-3)] were measured. Skeletal muscle biopsies were obtained from the vastus lateralis muscle to measure citrate synthase (CS) and Complex III activity. Regression analyses were used to examine predictors of mitochondrial mass and activity.

Results

CS activity was negatively associated with VAT (r² = 0.360, p < 0.001), CRP (r² = 0.168, p = 0.047), and positively associated with testosterone (r² = 0.145, p = 0.042). Complex III activity was negatively associated with VAT relative to total lean mass (VAT:TLM) (r² = 0.169, p = 0.033), trended for CRP (r² = 0.142, p = 0.069), and positively associated with testosterone (r² = 0.224, p = 0.010). Multiple regression showed CS activity was significantly associated with VAT + CRP (r² = 0.412, p = 0.008) and VAT + Testosterone (r² = 0.433, p = 0.001). Complex III activity was significantly associated with VAT relative to total trunk cross-sectional area (CSA) + CRP (VAT:total trunk CSA + CRP; r² = 0.286, p = 0.048) and VAT + Testosterone (r² = 0.277, p = 0.024).

Conclusion

Increased visceral adiposity and associated inflammatory signaling (CRP) along with reduced testosterone levels predict mitochondrial dysfunction following SCI. Specifically, lower VAT_CSA and higher testosterone levels or lower VAT_CSA and lower CRP levels positively predict mitochondrial mass and enzyme activity in persons with chronic SCI. Future research should investigate the efficacy of diet, exercise, and potentially testosterone replacement therapy on enhancing mitochondrial health in chronic SCI.

Clinical Trial Registration

[www.ClinicalTrials.gov], identifier: [NCT02660073].

Connectedness to Nature Does Not Explain the Variation in Physical Activity and Body Composition in Adults and Older People

Connectedness to nature (CN) is a significant predictor of pro-environmental behaviours, human health and well-being. However, research on how this connection to the natural world might promote a more active lifestyle and improve body mass composition according to gender is lacking. This study investigated the influence of CN on physical activity (PA) and body composition in adults and older people. We recruited a sample of 219 individuals (77 men and 142 women), and a self-administered questionnaire was used to measure CN and obtain demographic data. Body composition was assessed by bioimpedance, and PA was assessed by accelerometry. Correlations and stepwise multiple regressions were used in data analysis. CN's association with other variables was more pronounced in women than in men, and we only identified significant associations with steps/day and body composition. However, this variable would not be included in the regression models that we developed. Adiposity levels and muscle status were significant predictors of PA in women. In both genders, age, percentage of fat mass and fat-free mass were selected as regressors in the models developed for visceral fat area and muscle condition (R2 Adjusted ≥ 0.908).

Accuracy of dual-energy x-ray absorptiometry for assessing longitudinal change in visceral adipose tissue in patients with coronary artery disease

BACKGROUND/OBJECTIVE

Visceral adipose tissue (VAT) is a key target of interventions for obesity-related diseases. Dual-energy x-ray absorptiometry (DXA) can estimate VAT, however its accuracy to measure longitudinal change in VAT compared to gold-standard techniques such as magnetic resonance imaging (MRI), has not been studied in adults. This study aimed to determine the accuracy of DXA compared with gold-standard MRI for cross-sectional VAT assessment, and for detecting longitudinal change in VAT.

METHODS

Adults with coronary artery disease (64 ± 8 years; BMI 27.8 ± 3.5 kg/m²; 88% male) were assessed for VAT by DXA and MRI at baseline (n = 34) and during implementation of an exercise intervention study at 3- and 12-months (n = 29). To match the 5.2 cm DXA measurement site for Hologic software (InnerCore^TM), VAT cross-sectional area (CSA) was measured by MRI using a single slice at L4/L5 junction, and VAT volume measured by 10 × 5 mm slices over the L4/L5 junction. MRI slices were quantified for VAT using semi-automated specialised software. Relationships between DXA and MRI for cross-sectional VAT and longitudinal change in VAT were determined by linear regression. Accuracy between the methods was assessed by Bland-Altman analysis, with data presented as mean difference (95% confidence interval), lower and upper limits of agreement (LoA).

RESULTS

Strong correlations were found between DXA-VAT and MRI-VAT at baseline (r = 0.90; p < 0.001), and longitudinal change in DXA-VAT and MRI-VAT over 3- and 12-months (r = 0.67; p < 0.001). In contrast, Bland-Altman analysis revealed significant overestimation by DXA-VAT volume at baseline by 13% [-104 cm³ (-157, -52 cm³), p < 0.001; LoA (-398, 189 cm³)], and underestimation of change in DXA-VAT volume over 3-months by 33% [-41 cm³ (-77, -4 cm³), p = 0.030; LoA (-228, 147 cm³)] and 12-months by 47% [-65 cm³ (-114, -17 cm³), p = 0.010; LoA (-316, 185 cm³)]. Results were similar for VAT CSA.

CONCLUSIONS

Compared with MRI, DXA substantially underestimated longitudinal changes in VAT. Therefore, DXA is not currently a valid alternative to MRI for quantifying VAT changes and may under-represent the effectiveness of interventions for obesity management.

Role of exercise on visceral adiposity after spinal cord injury: a cardiometabolic risk factor

PURPOSE

Visceral adipose tissue (VAT) is associated with cardiometabolic disease risk in able-bodied (AB) populations. However, the underlying mechanisms of VAT-induced disease risk are unknown in persons with spinal cord injury (SCI). Potential mechanisms of VAT-induced cardiometabolic dysfunction in persons with SCI include systemic inflammation, liver adiposity, mitochondrial dysfunction, and anabolic deficiency. Moreover, how exercise interventions impact these mechanisms associated with VAT-induced cardiometabolic dysfunction are still being explored.

METHODS

A search for relevant scientific literature about the effects of exercise on VAT and cardiometabolic health was conducted on the PubMed database. Literature from reference lists was also included when appropriate.

RESULTS

Both aerobic and resistance exercise training beneficially impact health and VAT mass via improving mitochondrial function, glucose effectiveness, and inflammatory signaling in SCI and AB populations. Specifically, aerobic exercise appears to also modulate cellular senescence in AB populations and animal models, while resistance exercise seems to augment anabolic signaling in persons with SCI.

CONCLUSIONS

The current evidence supports regular engagement in exercise to reduce VAT mass and the adverse effects on cardiometabolic health in persons with SCI. Future research is needed to further elucidate the precise mechanisms by which VAT negatively impacts health following SCI. This will likely facilitate the development of rehabilitation protocols that target VAT reduction in persons with SCI.

Feasibility of quantifying change in immune white cells in abdominal adipose tissue in response to an immune modulator in clinical obesity

Background

Obesity is often associated with inflammation in adipose tissue (AT) with release of mediators of atherogenesis. We postulated that it would be feasible to collect sufficient abdominal AT to quantify changes in a broad array of adaptive and innate mononuclear white cells in obese non-diabetic adults in response to a dipeptidyl protease inhibitor (DPP4i), known to inhibit activation of immune white cells.

Methods

Adults 18–55 years-of-age were screened for abdominal obesity and insulin resistance or impaired glucose tolerance but without known inflammatory conditions. Twenty-one eligible participants consented for study and were randomized 3:1 to receive sitagliptin (DPP4i) at 100mg or matching placebo daily for 28 days. Abdominal AT collected by percutaneous biopsy and peripheral blood mononuclear cell fractions were evaluated before and after treatment; plasma was stored for batch testing.

Results

Highly sensitive C-reactive protein, a global marker of inflammation, was not elevated in the study population. Innate lymphoid cells (ILC) type 3 (ILC-3) in abdominal AT decreased with active treatment compared with placebo (p = 0.04). Other immune white cells in AT and peripheral blood mononuclear cell (PBMC) fractions did not change with treatment compared to placebo (p>0.05); although ILC-2 declined in PBMCs (p = 0.007) in the sitagliptin treatment group. Two circulating biomarkers of atherogenesis, interferon-inducible protein-10 (IP-10) and sCD40L declined in plasma (p = 0.02 and p = 0.07, respectively) in the active treatment group, providing indirect validation of a net reduction in inflammation.

Conclusions

In this pilot study, two cell types of the innate lymphoid system, ILC-3 in AT and ILC-2 PBMCs declined during treatment and as did circulating biomarkers of atherogenesis. Changes in other immune cells were not demonstrable. The study showed that sufficient abdominal AT could be obtained to quantify white cells of both innate and adaptive immunity and to demonstrate changes during therapy with an immune inhibitor.

Trial registration

ClinicalTrials.gov identifier (NCT number): NCT02576

Visceral adiposity and liver fat as mediators of the association between cardiorespiratory fitness and plasma glucose-insulin homeostasis

Cardiorespiratory fitness (CRF) is positively associated with insulin sensitivity, whereas excessive levels of visceral adipose tissue (AT) and liver fat (LF) are both associated with insulin resistance and impaired plasma glucose-insulin homeostasis. To what extent levels of visceral AT and LF content contribute to the relationship between CRF and indices of plasma glucose-insulin homeostasis is uncertain. Our objective was to explore the interactions among CRF, visceral AT, and LF with glucose tolerance/insulin levels in asymptomatic and apparently healthy individuals. CRF was measured in 135 women and 177 men with a maximal treadmill graded exercise test. Indices of plasma glucose-insulin homeostasis were derived from a 3-h oral glucose tolerance test (OGTT) performed in the morning after a 12-h fast. Visceral AT levels and LF content were measured using magnetic resonance imaging and spectroscopy. For any given CRF level, women presented significantly lower visceral AT and LF than men as well as lower homeostasis model assessment of insulin resistance (HOMA-IR) and plasma glucose-insulin levels during the OGTT compared with men. In both sexes, there were significant negative correlations between CRF and HOMA-IR as well as glucose and insulin levels measured during the OGTT. Both glucose and insulin levels during the OGTT correlated positively with visceral AT and LF. In women and men, being in the top CRF tertile was associated with low levels of visceral AT and LF. Multivariable linear regression analyses suggested that visceral AT and LF were plausible mediators of the association between CRF and indices of plasma glucose-insulin homeostasis.

HIV and antiretroviral therapy-related fat alterations

Early in the HIV epidemic, lipodystrophy, characterized by subcutaneous fat loss (lipoatrophy), with or without central fat accumulation (lipohypertrophy), was recognized as a frequent condition among people living with HIV (PLWH) receiving combination antiretroviral therapy. The subsequent identification of thymidine analogue nucleoside reverse transcriptase inhibitors as the cause of lipoatrophy led to the development of newer antiretroviral agents; however, studies have demonstrated continued abnormalities in fat and/or lipid storage in PLWH treated with newer drugs (including integrase inhibitor-based regimens), with fat gain due to restoration to health in antiretroviral therapy-naive PLWH, which is compounded by the rising rates of obesity. The mechanisms of fat alterations in PLWH are complex, multifactorial and not fully understood, although they are known to result in part from the direct effects of HIV proteins and antiretroviral agents on adipocyte health, genetic factors, increased microbial translocation, changes in the adaptive immune milieu after infection, increased tissue inflammation and accelerated fibrosis. Management includes classical lifestyle alterations with a role for pharmacological therapies and surgery in some patients. Continued fat alterations in PLWH will have an important effect on lifespan, healthspan and quality of life as patients age worldwide, highlighting the need to investigate the critical uncertainties regarding pathophysiology, risk factors and management.

Apolipoprotein B Levels Predict Future Development of Hypertension Independent of Visceral Adiposity and Insulin Sensitivity

BACKGROUND

High plasma apolipoprotein B (apoB) levels have been shown to be associated with hypertension, central obesity, and insulin resistance in cross-sectional research. However, it is unclear whether apoB levels predict future hypertension independent of body composition and insulin sensitivity. Therefore, we prospectively investigated whether plasma apoB concentrations independently predicted the risk of hypertension in a cohort of Japanese Americans.

METHODS

A total of 233 normotensive Japanese Americans (77 men, 156 women; mean age, 46.4±11.0 years) were followed over 10 years to monitor them for the development of hypertension. Fasting plasma concentrations of apoB, glucose, and insulin were measured at baseline. Insulin sensitivity was estimated using the homeostasis model assessment of insulin resistance (HOMA-IR). The abdominal visceral and subcutaneous fat areas were measured at baseline using computed tomography. Logistic regression analysis was used to estimate the association between apoB concentrations and the odds of incident hypertension.

RESULTS

The 10-year cumulative incidence of hypertension was 21.5%. The baseline apoB level was found to be positively associated with the odds of incident hypertension over 10 years after adjustment for age, sex, body mass index, systolic blood pressure, abdominal visceral fat area, abdominal subcutaneous fat area, total plasma cholesterol concentration, diabetes status, and HOMA-IR at baseline (odds ratio and 95% confidence interval for a 1-standard deviation increase, 1.89 [1.06 to 3.37]; P=0.030).

CONCLUSION

Higher apoB concentrations predicted greater risks of future hypertension independent of abdominal visceral fat area and insulin sensitivity in Japanese Americans.

Computerised tomography skeletal muscle and adipose surface area values in a healthy Caucasian population

BACKGROUND

The analysis of computerised tomography (CT) images to provide body composition data has grown exponentially. Despite this, there remains limited published data defining the normal range of skeletal muscle area and adipose tissue area using CT. The aim of this study was to determine age- and sex-specific body composition values using CT at the level of the third lumbar vertebrae, in a Caucasian population with a healthy body mass index (BMI). In addition, we sought to develop threshold values for low skeletal muscle mass using these data.

METHODS

We included 107 healthy Caucasian patients (46 males; 61 females) with a healthy BMI (18-25 kg/m²) for analysis. Body composition data were obtained from a single transverse CT image at the mid-third lumbar vertebrae using ImageJ software. Tissue segmentation was performed using Hounsfield unit thresholds of -29 to +150 for muscle and -190 to -30 for adipose tissue.

RESULTS

The mean age of the study cohort was 47.8 ± 11.0 years (range 21-73) with a median BMI of 23.7 kg/m² (interquartile range 22.3-24.8). Patients were sub-divided into age above or below 50 years. Cut-offs for low muscle quantity, representing two standard deviations below the young healthy population mean values, were 43.5 cm²/m² for males and 30.0 cm²/m² for females.

CONCLUSIONS

Our data provide an insight into the distribution of skeletal muscle and adipose tissue surface area values measured on CT from a healthy Caucasian population. Our CT-derived cut-offs for low muscle quantity, based on international guidelines, are much lower than those previously suggested.

Analysis of risk factors for carotid intima-media thickness in patients with type 2 diabetes mellitus in Western China assessed by logistic regression combined with a decision tree model

BACKGROUND

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in patients with type 2 diabetes (T2DM). Carotid intima-media thickness (CIMT) is considered a preclinical stage of atherosclerosis. Therefore, it is necessary to identify the related risk factors for CIMT to facilitate the early prevention of CVD. Previous studies have shown that visceral fat area (VFA) is a risk factor for T2DM and CVD. However, few studies have focused on the effects of VFA on CIMT associated with T2DM. Moreover, considering that the body fat distribution shows regional and racial heterogeneity, the purpose of this study was to investigate the predictive value of VFA and other risk factors for CIMT associated with T2DM in Western China.

METHODS

In a cross-sectional study, a total of 1372 patients with T2DM were divided into the CIMT (-) group (n = 965) and the CIMT (+) group (n = 407) based on CIMT values. In addition to the univariate analyses, logistic regression analysis and a decision tree model were simultaneously performed to establish a correlation factor model for CIMT.

RESULTS

Univariate analyses showed that sex, smoking status, age, heart rate, systolic blood pressure (SBP), diastolic blood pressure (DBP), height, weight, body mass index (BMI), waist circumference, hip circumference, waist-hip ratio, VFA, subcutaneous fat area, and the levels of 2-h C-peptide, serum creatinine, urea nitrogen and uric acid were significantly different between the two groups (all p < 0.05). Smoking, increased VFA, female sex and increased BMI were risk factors in the logistic regression analyses (OR = 5.759, OR = 1.364, OR = 2.239, OR = 1.186, respectively). In the decision tree model, smoking was the root node, followed by sex, waist circumference, VFA and chronic kidney disease (CKD) in order of importance.

CONCLUSIONS

In addition to smoking, sex and BMI, VFA has a significant effect on CIMT associated with T2DM in the Chinese Han population in Western China. In addition, the decision tree model could help clinicians make more effective decisions, with its simplicity and intuitiveness, making it worth promoting in future medical research.Trial registration ChiCTR, ChiCTR1900027739. Registered 24 November 2019-Retrospectively registered, http://www.chictr.org.cn/index.aspx.

Advantages and disadvantages of different methods for diagnosis of visceral obesity

This analytical review is devoted to the study of visceral obesity as a risk factor for the development and progression of cardiovascular diseases. The presented review discusses the evolution of methods for diagnosis of visceral obesity, their advantages and limitation for various ectopic fat depots.

Circulating glutamate concentration as a biomarker of visceral obesity and associated metabolic alterations

Background

Visceral adipose tissue (VAT) area is a strong predictor of obesity-related cardiometabolic alterations, but its measurement is costly, time consuming and, in some cases, involves radiation exposure. Glutamate, a by-product of branched-chain-amino-acid (BCAA) catabolism, has been shown to be increased in visceral obese individuals. In this follow-up data analysis, we aimed to investigate the ability of plasma glutamate to identify individuals with visceral obesity and concomitant metabolic alterations.

Methods

Measurements of adiposity, targeted blood metabolomics and cardiometabolic risk factors were performed in 59 healthy middle-aged women. Visceral and subcutaneous adipose tissue areas were measured by computed tomography (CT) whereas body fat and lean mass were assessed by dual-energy x-ray absorptiometry (DEXA).

Results

The univariate Pearson correlation coefficient between glutamate and VAT area was r = 0.46 (p < 0.001) and it was r = 0.36 (p = 0.006) when adjusted for total body fat mass. Glutamate allowed to identify individuals with VAT areas ≥100 cm² (ROC_AUC: 0.78, 95% CI: 0.66–0.91) and VAT ≥130 cm² (ROC_AUC: 0.71, 95% CI: 0.56–0.87). The optimal glutamate concentration threshold determined from the ROC curve (glutamate ≥34.6 μmol/L) had a greater sensitivity than the metabolic syndrome (MetS) and the hypertriglyceridemic waist (HTW) phenotype to identify individuals with VAT ≥100 cm² (83% for glutamate vs 52% for the MetS and 35% for the HTW). Variance analysis showed that women with a high circulating glutamate level (≥34.6 μmol/L) had an altered metabolic profile, particularly regarding total triglyceride levels and the amount of triglycerides and cholesterol in very-low-density lipoproteins (all p < 0.01).

Conclusion

Circulating glutamate is strongly associated with VAT area and may represent a potential screening tool for visceral obesity and alterations of the metabolic profile.

Exercise training and/or diet on reduction of intra-abdominal adipose tissue and risk factors for cardiovascular disease

BACKGROUND/OBJECTIVES

To test the effects of weight loss with and without exercise training (aerobic or resistance) on intra-abdominal adipose tissue (IAAT) and risk factors for cardiovascular disease (CVD). Additionally, CVD risk factors was evaluated before and after weight loss using previously established IAAT cut-points.

SUBJECTS/METHODS

One hundred twenty-two overweight premenopausal women were randomly assigned to one of three groups: (1) diet only (Diet); (2) diet and aerobic training (Diet + AT); or (3) diet and resistance training (Diet + RT); until a BMI of < 25 kg/m² was reached. Computerized tomography was used to measure IAAT and blood lipids were measured by assay. Evaluations were made before and after weight loss.

RESULTS

Though no group-by-time effects were found after weight loss, we observed significant time effects for: IAAT (-38.0%, P < 0.001), total cholesterol (TC) (-2.2%, P = 0.008), low-density lipoprotein cholesterol (LDL-C) (-4.8%, P < 0.001), high-density lipoprotein cholesterol (HDL-C) (+20.2%, P < 0.001), triglycerides (-18.7%, P < 0.001), TC/HDL-C (-16.3%, P < 0.001), and LDL-C/HDL-C (-18.0%, P < 0.001). Following weight loss, 40.2% of all participants reduced IAAT to < 40 cm² (IAAT associated with low CVD risk). Furthermore, only 2.5% of participants had an IAAT > 110 cm² (IAAT associated with high CVD risk) after weight loss. We also observed that decreases of IAAT were associated with decreased CVD risk factors after weight loss independent of race, changes in %fat mass and changes in maximal oxygen uptake.

CONCLUSIONS

Caloric restriction leading to significant weight loss with or without exercise training appears to be equally effective for reducing IAAT and CVD risk factors.

Low muscle quality in Japanese type 2 diabetic patients with visceral fat accumulation

Background

Although obesity-related type 2 diabetes mellitus (T2DM) and sarcopenia in the elderly have been increasing worldwide, the associations among visceral fat accumulation, skeletal muscle indices (mass, strength, and quality) and cardiovascular diseases in T2DM remain poorly investigated.

Methods

We enrolled 183 Japanese T2DM inpatients (126 men, 57 women; mean age 64.7 ± 12.6 years, ± SD). The estimated-visceral fat area (eVFA) and skeletal muscle mass were measured by each device using bioelectrical impedance analysis method. We also measured grip strength by dynamometer and motor nerve conduction velocity (MCV). We analyzed the difference in skeletal muscle indices between T2DM patients with and without visceral fat accumulation, and examined the impact of skeletal muscle indices on cardiovascular diseases in patients with visceral fat accumulation.

Results

The prevalence of sarcopenia defined by the Consensus of Asian Working Group for Sarcopenia and low skeletal muscle mass were both lower in the visceral fat accumulation (+) group than in (−) group. However, the prevalence of weak hand grip strength was similar in the visceral fat accumulation (−) and (+) groups, indicating that considerable patients with visceral fat accumulation had weak grip strength in spite of fair skeletal muscle mass. Muscle quality [grip strength (kg)/arm muscle mass (kg)] was significantly lower in patients with visceral fat accumulation. Multiple regression analysis identified eVFA, MCV and sex as significant and independent determinants of muscle quality. In visceral fat accumulation (+) group, the patients with low muscle quality had longer duration of diabetes, lower eGFR, higher serum adiponectin, lower MCV and higher prevalence of cardiovascular diseases, compared to the patients with high muscle quality. Finally, sex- and age-adjusted models showed significant association between low muscle quality and cardiovascular diseases in all subjects (odds ratio 2.28, p = 0.012), especially in patients with visceral fat accumulation (odds ratio 2.72, p = 0.018).

Conclusions

T2DM patients with visceral fat accumulation had low muscle quality, and patients with low muscle quality were more affected with cardiovascular diseases.

Electronic supplementary material

The online version of this article (10.1186/s12933-018-0755-3) contains supplementary material, which is available to authorized users.

Abdominal obesity, sarcopenia, and osteoporosis are associated with frailty in men living with and without HIV

OBJECTIVE

The relationships between frailty and body composition in older adults with HIV infection are poorly understood. We sought to describe associations between frailty and measures of body composition among adult men with HIV and without HIV.

DESIGN/METHODS

Men with and without HIV (age 50-69 years) in the Multicenter AIDS Cohort Study (MACS) Bone Strength Substudy were included if evaluated for frailty (by Fried phenotype) and body composition [BMI, waist circumference, abdominal visceral (VAT) and subcutaneous (SAT) adipose tissue, sarcopenia, and osteopenia/osteoporosis]. All participants with HIV infection were on antiretroviral therapy. Multivariate multinomial logistic regression models were used to determine associations of frailty with body composition.

RESULTS

A total of 399 men, including 199 men with HIV and 200 men without HIV, both with median age 60 years, constituted our study population. Frailty prevalence was 16% (men with HIV) vs. 8% (men without HIV). HIV serostatus was associated with a 2.43 times higher odds of frailty (P = 0.01). Higher waist circumference, VAT, sarcopenia, and femoral neck osteoporosis were associated with increased odds of frailty (aOR 4.18, 4.45, 4.15, and 13.6, respectively, and all P < 0.05); BMI and SAT were not. None of these measures presented a differential association with frailty by HIV serostatus (all P > 0.20).

CONCLUSION

Higher abdominal obesity and sarcopenia were associated with frailty among men with and without HIV. Assessment of these body composition parameters may help detect frailty in the clinical setting.

Impact of hypercortisolism on skeletal muscle mass and adipose tissue mass in patients with adrenal adenomas

CONTEXT

Abdominal visceral adiposity and central sarcopenia are markers of increased cardiovascular risk and mortality.

OBJECTIVE

To assess whether central sarcopenia and adiposity can serve as a marker of disease severity in patients with adrenal adenomas and glucocorticoid secretory autonomy.

DESIGN

Retrospective cohort study.

PATIENTS

Twenty-five patients with overt Cushing's syndrome (CS), 48 patients with mild autonomous cortisol excess (MACE) and 32 patients with a nonfunctioning adrenal tumour (NFAT) were included.

METHODS

Medical records were reviewed, and body composition measurements (visceral fat [VAT], subcutaneous fat [SAT], visceral/total fat [V/T], visceral/subcutaneous [V/S] and total abdominal muscle mass) were calculated based on abdominal computed tomography (CT).

RESULTS

In patients with overt CS, when compared to patients with NFAT, the V/T fat and the V/S ratio were increased by 0.08 (P < .001) and by 0.3 (P < .001); however, these measurements were decreased by 0.04 (P = .007) and 0.2 (P = .01), respectively, in patients with MACE. Total muscle mass was decreased by -10 cm² (P = .02) in patients with overt CS compared to patients with NFAT. Correlation with morning serum cortisol concentrations after dexamethasone suppression testing revealed that for every 28 nmol/L cortisol increase there was a 0.008 increase in V/T (P < .001), 0.02 increase in the V/S fat ratio (P < .001) and a 1.2 cm² decrease in mean total muscle mass (P = .002).

CONCLUSIONS

The severity of hypercortisolism was correlated with lower muscle mass and higher visceral adiposity. These CT-based markers may allow for a more reliable and objective assessment of glucocorticoid-related disease severity in patients with adrenal adenomas.

Osteoporosis, obesity, and sarcopenia on abdominal CT: a review of epidemiology, diagnostic criteria, and management strategies for the reporting radiologist

Abdominal computed tomography (CT) is a widely performed examination, with many indications. Assessment of bone, fat, and muscle on abdominal CT can be performed in a quantitative manner. Published studies have developed diagnostic cutoffs for osteoporosis, obesity, and sarcopenia, which are summarized with pictorial examples. The epidemiological and prognostic significance of these disease states are outlined. Further diagnostic steps and treatment strategies are outlined to inform both the managing clinician and reporting radiologist. This article summarizes an unglamorous yet information-rich field, which is ripe for assessment in the dawning era of personalized medicine, and one in which the radiologist is well placed to add value to patient care.

Obesity as predictor of postoperative outcomes in liver transplant candidates: Review of the literature and future perspectives

BACKGROUND

Current American and European guidelines consider a pre-transplant BMI ≥40kg/m² as a relative contraindication for liver transplantation but this recommendation is graded as uncertain and requires further research. Moreover, conflicting results are reported on the predictive value of BMI 30-39.9kg/m² on post-transplant complication and mortality risk.

AIM

This study analyzed the data of the literature on the effect of all three BMI classes of obesity on postoperative outcomes in liver transplantation.

MATERIALS AND METHODS

A PubMed and Cochrane Library search was conducted from inception to October 2015.

RESULTS

Analysis of the literature demonstrates that discrepancies among studies are mainly either due to limitations of BMI per se, the different BMI cut-offs used to select patients with obesity or reference group and the different outcomes considered. Moreover, the evaluation of visceral adipose tissue and the detrimental effect of muscle mass reduction in presence of obesity are never considered.

CONCLUSIONS

BMI assessment should be used as a preliminary method to evaluate obesity. Subsequently, the assessment of visceral adipose tissue and muscle mass should complete the preoperative evaluation of liver transplant candidates. This innovative approach could represent a new field of research in liver transplantation.

Cardiometabolic risk factors in type 2 diabetes with high fat and low muscle mass: At baseline and in response to exercise

OBJECTIVE

To examine the interplay between high fat and low muscle mass on cardiometabolic risk factors at baseline and in response to exercise in type 2 diabetes.

METHODS

Using baseline percent body fat and skeletal muscle mass index, 248 participants were divided into high fat versus low fat and low muscle versus high muscle. Linear mixed models were used to examine the main effects of fat mass and muscle mass and their interaction on baseline cardiometabolic risk factors and changes in risk factors in response to 6-month exercise training.

RESULTS

At baseline, there was a fat mass by muscle mass interaction effect on hemoglobin A_1c (HbA_1c ; P = 0.009), suggesting that low muscle was associated with elevated HbA_1c in those with high fat but not low fat. Significant interactions between baseline fat mass and muscle mass on the exercise-induced changes in visceral adipose tissue, insulin resistance, and triglyceride concentration indicated that low muscle attenuated the exercise responses in participants with high fat at baseline (all P < 0.05).

CONCLUSIONS

High fat and low muscle may be synergistically associated with higher HbA_1c in type 2 diabetes. In participants with high fat mass, low muscle mass may attenuate exercise-induced improvements in some cardiometabolic risk factors.

Increased risk of subclinical atherosclerosis associated with high visceral adiposity index in apparently healthy Korean adults: the Kangbuk Samsung Health Study

BACKGROUND

The visceral adiposity index (VAI) is a mathematical tool that reflects a patient's visceral adiposity and insulin resistance. Recent studies have noted an association between VAI and cardiovascular event. We analyzed the association between VAI and coronary artery calcium score (CACS) in Korean adults.

METHODS

For 33,468 participants (mean age 42 yrs) in a health screening program, VAI was calculated using the following formulae: [waist circumference (WC)/{39.68 + (1.88 * body mass index (BMI))}] * (triglyceride/1.03) * {1.31/high-density lipoprotein cholesterol (HDL-C)} for men and [WC/{36.58 + (1.89 * BMI)}] * (triglyceride/0.81) * (1.52/HDL-C) for women. Coronary artery calcium scores were measured with multi-detector computed tomography.

RESULTS

CACS was positively correlated with VAI (r = 0.027, p < 0.001). Subjects with 0 < CACS <100 and CACS ≥ 100 had significantly higher VAI compared to those with CACS = 0 (2.04 ± 1.97, 2.08 ± 1.67 vs. 1.68 ± 1.50, p < 0.001). In logistic regression analyses with CACS >0 as the dependent variable, subjects in the highest tertile of VAI (>1.777) had significantly increased odds ratio for CACS >0 compared to subjects in the lowest tertile (<0.967), even after adjusting for confounding variables, including BMI (OR 1.26, 95% CI 1.147-1.381).

CONCLUSIONS

Subjects with high VAI had increased risk for subclinical atherosclerosis, as assessed by CACS. Key messages Recent studies have noted an association between visceral adiposity index (VAI) and cardiovascular event. Subjects with coronary artery calcification (CAC) showed significantly higher VAI compared to those without CAC. The subjects with high VAI showed increased odds ratio for CAC as compared to subjects with low VAI, suggesting high VAI reflects increased risk for subclinical atherosclerosis.

Visceral Adiposity is a Risk Factor for Poor Prognosis in Colorectal Cancer Patients Receiving Adjuvant Chemotherapy

BACKGROUND

Studies utilizing body mass index (BMI) have failed to show a consistent relationship between obesity and survival following treatment for colorectal cancer (CRC). Computerized tomography (CT) offers a reliable alternative approach to quantify body adiposity. We hypothesized that visceral obesity may negatively impact survival in CRC patients.

AIMS AND METHODS

A retrospective review of CRC patients who received adjuvant chemotherapy at a single center during the period 2006-2009 identified from a prospectively maintained database. Visceral adiposity was determined by measuring visceral fat area (VFA) on preoperative staging CT. All patients were followed up to study completion or death.

RESULTS

Sixty-two CRC patients with a mean age of 63.2 years received adjuvant chemotherapy and had imaging available for analysis. Thirty-five patients (56.5 %) had node positive disease. Thirty-one patients (50 %) were classified viscerally obese based on staging CT. 85.4 % of the patients completed adjuvant chemotherapy and visceral obesity was not associated with increased toxicity or failure to complete treatment. After a median follow-up of 65.2 months, patients with visceral obesity had a significantly lower overall survival (OS) (54.8 % vs 87.1 %, p = 0.004) and disease-free survival (DFS) (48.4 vs 77.4 %, p = 0.007) compared with patients without visceral obesity. There was no relationship between BMI and survival. Multivariate analysis using Cox proportional hazards model showed that visceral obesity was independently associated with reduced OS (Hazard ratio = 7.0; 95 % CI 2.0-24.6; p = 0.002).

CONCLUSION

This study shows that visceral obesity increases the likelihood of a poor prognosis in CRC patients receiving adjuvant chemotherapy thus underlying the value of lifestyle interventions to minimize visceral obesity in this patient cohort.

Association between high visceral fat area and postoperative complications in patients with Crohn's disease following primary surgery

AIM

The aim of this study was to determine the association between visceral fat area (VFA) on CT and postoperative complications after primary surgery in patients with Crohn's disease (CD).

METHOD

Inclusion criteria were patients with a confirmed diagnosis of CD who had preoperative abdominal CT scan. The areas of total fat, subcutaneous fat and visceral fat were measured using an established image-analysis method at the lumbar 3 (L3) level on CT cross-sectional images. Visceral obesity was defined as a visceral fat area (VFA) of ≥ 130 cm(2) . Clinical variables, intra-operative outcomes and postoperative courses within 30 days were analysed.

RESULTS

A total of 164 patients met the inclusion criteria. Sixty-three (38.4%) patients had postoperative complications. The mean age of the patients with complications (the study group) was 40.4 ± 15.4 years and of those without complications (the control group) was 35.8 ± 12.9 years (P = 0.049). There were no differences in disease location and behaviour between patients with or without complications (P > 0.05). In multivariable analysis, VFA [odds ratio (OR) = 2.69; 95% confidence interval (CI): 1.09-6.62; P = 0.032] and corticosteroid use (OR = 2.86; 95% CI: 1.32-6.21; P = 0.008) were found to be associated with postoperative complications. Patients with visceral obesity had a significantly longer operative time (P = 0.012), more blood loss (P = 0.019), longer bowel resection length (P = 0.003), postoperative ileus (P = 0.039) and a greater number of complications overall (P < 0.001).

CONCLUSION

High VFA was found to be associated with an increased risk for 30-day postoperative complications in patients with CD undergoing primary surgery.

The Correlation between the Triglyceride to High Density Lipoprotein Cholesterol Ratio and Computed Tomography-Measured Visceral Fat and Cardiovascular Disease Risk Factors in Local Adult Male Subjects

Background

We studied the association between the triglyceride to high-density lipoprotein cholesterol ratio and computed tomography-measured visceral fat as well as cardiovascular risk factors among Korean male adults.

Methods

We measured triglycerides, high density lipoprotein cholesterol, body mass, waist circumference, fasting plasma glucose, hemoglobin A1c, systolic blood pressure, diastolic blood pressure, visceral fat, and subcutaneous fat among 372 Korean men. The visceral fat and subcutaneous fat areas were measured by computed tomography using a single computed tomography slice at the L4-5 lumbar level. We analyzed the association between the triglyceride to high density lipoprotein cholesterol ratio and visceral fat as well as cardiovascular risk factors.

Results

A positive correlation was found between the triglyceride to high density lipoprotein cholesterol ratio and variables such as body mass index, waist circumference, fasting plasma glucose, hemoglobin A1c, visceral fat, and the visceral-subcutaneous fat ratio. However, there was no significant correlation between the triglyceride to high density lipoprotein cholesterol ratio and subcutaneous fat or blood pressure. Multiple logistic regression analyses revealed significant associations between a triglyceride to high density lipoprotein cholesterol ratio ≥3 and diabetes, a body mass index ≥25 kg/m², a waist circumference ≥90 cm, and a visceral fat area ≥100 cm². The triglyceride to high density lipoprotein cholesterol ratio was not significantly associated with hypertension.

Conclusion

There were significant associations between the triglyceride to high density lipoprotein cholesterol ratio and body mass, waist circumference, diabetes, and visceral fat among a clinical sample of Korean men. In the clinical setting, the triglyceride to high density lipoprotein cholesterol ratio may be a simple and useful indicator for visceral obesity and cardiovascular disease.

Visceral obesity: A new risk factor for stone disease

INTRODUCTION

We examined the relationship between stone disease and the amount of visceral adipose tissue measured with unenhanced computed tomography (CT).

METHODS

We included 149 patients with complaints of flank pain and kidney stones detected by CT, from August 2012 to April 2013. In addition, as the control group we included 139 healthy individuals, with flank pain within the same time period, with no previous history of urological disease and no current kidney stones identified by CT. Patients were analyzed for age, gender, body mass index, amount of visceral and subcutaneous adipose tissue, and serum level of low-density lipoprotein and triglyceride.

RESULTS

There were no differences between groups in terms of gender and age (p = 0.27 and 0.06, respectively). Respective measurements for the stone and control groups for body mass index were 29.1 and 27.6 kg/m(2); for visceral fat measurement 186.0 and 120.2 cm(2); and for subcutaneous fat measurements 275.9 and 261.9 cm(2) (p = 0.01; 0.01 and 0.36, respectively). Using multivariate analysis, the following factors were identified as increasing the risk of kidney stone formation: hyperlipidemia (p = 0.003), hypertension (p = 0.001), and ratio of visceral fat tissue to subcutaneous fat tissue (p = 0.01). Our study has its limitations, including its retrospective nature, its small sample size, possible selection bias, and missing data. The lack of stone composition data is another major limitation of our study.

CONCLUSION

The ratio of visceral to subcutaneous adipose tissue, in addition to obesity, hyperlipidemia, and hypertension, was identified as an emerging factor in the formation of kidney stones.

Predictors of Treatment Response to Tesamorelin, a Growth Hormone-Releasing Factor Analog, in HIV-Infected Patients with Excess Abdominal Fat

BACKGROUND

Tesamorelin, a synthetic analog of human growth hormone-releasing factor, decreases visceral adipose tissue (VAT) in human immunodeficiency virus (HIV)-infected patients with lipodystrophy.

OBJECTIVES

1) To evaluate the utility of patient characteristics and validated disease-risk scores, namely indicator variables for the metabolic syndrome defined by the International Diabetes Federation (MetS-IDF) or the National Cholesterol Education Program (MetS-NCEP) and the Framingham Risk Score (FRS), as predictors of VAT reduction during tesamorelin therapy at 3 and 6 months, and 2) To explore the characteristics of patients who reached a threshold of VAT <140 cm2, a level associated with lower risk of adverse health outcomes, after 6 months of treatment with tesamorelin.

METHODS

Data were analyzed from two Phase 3 studies in which HIV-infected patients with excess abdominal fat were randomized in a 2:1 ratio to receive tesamorelin 2 mg (n = 543) or placebo (n = 263) subcutaneously daily for 6 months, using ANOVA and ANCOVA models.

RESULTS

Metabolic syndrome (MetS-IDF or MetS-NCEP) and FRS were significantly associated with VAT at baseline. Presence of metabolic syndrome ([MetS-NCEP), triglyceride levels >1.7 mmol/L, and white race had a significant impact on likelihood of response to tesamorelin after 6 months of therapy (interaction p-values 0.054, 0.063, and 0.025, respectively). No predictive factors were identified at 3 months. The odds of a VAT reduction to <140 cm2 for subjects treated with tesamorelin was 3.9 times greater than that of subjects randomized to placebo after controlling for study, gender, baseline body mass index (BMI) and baseline VAT (95% confidence interval [CI] 2.03; 7.44).

CONCLUSIONS

Individuals with baseline MetS-NCEP, elevated triglyceride levels, or white race were most likely to experience reductions in VAT after 6 months of tesamorelin treatment. The odds of response of VAT <140 cm2 was 3.9 times greater for tesamorelin-treated patients than that of patients receiving placebo.

Effects of Light Intensity Activity on CVD Risk Factors: A Systematic Review of Intervention Studies

The effects of light intensity physical activity (LIPA) on cardiovascular disease (CVD) risk factors remain to be established. This review summarizes the effects of LIPA on CVD risk factors and CVD-related markers in adults. A systematic search of four electronic databases (PubMed, Academic Search Complete, SPORTDiscus, and CINAHL) examining LIPA and CVD risk factors (body composition, blood pressure, glucose, insulin, glycosylated hemoglobin, and lipid profile) and CVD-related markers (maximal oxygen uptake, heart rate, C-reactive protein, interleukin-6, tumor necrosis factor-alpha, and tumor necrosis factor receptors 1 and 2) published between 1970 and 2015 was performed on 15 March 2015. A total of 33 intervention studies examining the effect of LIPA on CVD risk factors and markers were included in this review. Results indicated that LIPA did not improve CVD risk factors and CVD-related markers in healthy individuals. LIPA was found to improve systolic and diastolic blood pressure in physically inactive populations with a medical condition. Reviewed studies show little support for the role of LIPA to reduce CVD risk factors. Many of the included studies were of low to fair study quality and used low doses of LIPA. Further studies are needed to establish the value of LIPA in reducing CVD risk.

Intrahepatic triglyceride content is independently associated with chronic kidney disease in obese adults: A cross-sectional study

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) and chronic kidney disease (CKD) are associated with some common critical cardio-metabolic risk factors. The aim of this study was to explore the association between intrahepatic triglyceride (IHTG) content and CKD in obese subjects.

METHODS

A total of 1068 obese participants received anthropometric, biochemical measurements and hepatic ultrasonography. Of those, 485 participants received magnetic resonance spectroscopy ((1)H-MRS) for the determination of IHTG content. CKD was defined as a urinary albumin:creatinine ratio (UACR)≥30 mg/g and/or estimated glomerular filtration rate (eGFR)<60 mL/min per 1.73 m(2).

RESULTS

The prevalence of CKD was significantly higher in NAFLD subjects compared to subjects without NAFLD, while the prevalence of CKD was gradually increased as the IHTG content increased by quartiles (P for trend<0.001). After adjustment for multivariate metabolic factors, the risk of abnormal albuminuria and CKD was increased by 68% [OR (95% CI): 1.68 (1.21-2.33), P<0.01] and 54% [OR (95% CI): 1.54 (1.14-2.07), P<0.01] respectively per one standard deviation (SD) increase in IHTG content. The association between IHTG content and CKD was not changed by conventional risk factors, including age, BMI and hypertension (all P<0.05).

CONCLUSION

IHTG content is independently associated with CKD in obese adults.

Stochastic effects in adaptive reconstruction of body damage: implied the creativity of natural selection

After an injury occurs, mechanical/biochemical loads on muscles influence the composition and structure of recovering muscles; this effect likely occurs in other tissues, cells and biological molecules as well owing to the similarity, interassociation and interaction among biochemical reactions and molecules. The 'damage and reconstruction' model provides an explanation for how an ideal cytoarchitecture is created by reducing components not suitable for bearing loads; in this model, adaptive changes are induced by promoting the stochasticity of biochemical reactions. Biochemical and mechanical loads can direct the stochasticity of biochemical reactions, which can in turn induce cellular changes. Thus, mechanical and biochemical loads, under natural selection pressure, modify the direction of cell- and tissue-level changes and guide the formation of new structures and traits, thereby influencing microevolution. In summary, the 'damage and reconstruction' model accounts for the role of natural selection in the formation of new organisms, helps explain punctuated equilibrium, and illustrates how macroevolution arises from microevolution.

Systemic arteriosclerosis and eating behavior in Japanese type 2 diabetic patients with visceral fat accumulation

Background

Visceral fat accumulation is a major etiological factor in the progression of type 2 diabetes mellitus and atherosclerosis. We described previously visceral fat accumulation and multiple cardiovascular risk factors in a considerable number of Japanese non-obese subjects (BMI <25 kg/m²). Here, we investigated differences in systemic arteriosclerosis, serum adiponectin concentration, and eating behavior in type 2 diabetic patients with and without visceral fat accumulation.

Methods

The study subjects were 75 Japanese type 2 diabetes mellitus (age: 64.8 ± 11.5 years, mean ± SD). Visceral fat accumulation represented an estimated visceral fat area of 100 cm² using the bioelectrical impedance analysis method. Subjects were divided into two groups; with (n = 53) and without (n = 22) visceral fat accumulation. Systemic arteriosclerosis was scored for four arteries by ultrasonography. Eating behavior was assessed based on The Guideline for Obesity questionnaire issued by the Japan Society for the Study of Obesity.

Results

The visceral fat accumulation (+) group showed significantly higher systemic vascular scores and significantly lower serum adiponectin levels than the visceral fat accumulation (−) group. With respect to the eating behavior questionnaire items, (+) patients showed higher values for the total score and many of the major sub-scores than (−) patients.

Conclusions

Type 2 diabetic patients with visceral fat accumulation showed 1) progression of systemic arteriosclerosis, 2) low serum adiponectin levels, and 3) differences in eating behavior, compared to those without visceral fat accumulation. Taken together, the findings highlight the importance of evaluating visceral fat area in type 2 diabetic patients. Furthermore, those with visceral fat accumulation might need to undergo more intensive screening for systemic arteriosclerosis and consider modifying their eating behaviors.

Associação entre o nível de atividade física e a área de gordura visceral em mulheres pós-menopáusicas

INTRODUÇÃO: O aumento da gordura visceral abdominal está associado à redução dos níveis de atividade física habitual e gera na mulher pós-menopáusica, o surgimento da doença da inatividade física, caracterizada pela manifestação de um conjunto de patologias, entre as quais se incluem diabetes mellitus do tipo 2 e doenças cardiovasculares. Por outro lado, a atividade física regular parece ter impacto significativo na prevenção tanto da gordura intra-abdominal quanto das complicações metabólicas e cardiovasculares.OBJETIVO: Verificar a associação entre a caminhada e a atividade física de moderada intensidade com a área de gordura intra-abdominal em mulheres pós-menopáusicas.MÉTODOS: A amostra foi composta por 239 mulheres com média de idade de 57,4 ± 6,6 anos participantes do programa "Menopausa em Forma". Para análise da atividade física foi utilizado o IPAQ versão longa. Consideraram-se os valores de 1.601 kcal/semana na caminhada e 2.283 kcal/semana na atividade física de moderada intensidade como suficientes para prevenção do excesso de gordura intra-abdominal. Utilizou-se a análise de regressão logística para estimar a odds ratio (OR), com intervalo de confiança de 95%.RESULTADOS: Após análise multivariada observou-se que a caminhada ofereceu proteção contra o excesso de gordura intra-abdominal, principalmente nas mulheres com períodos menstruais regulares, OR = 0,22 (0,08-0,62) e que não fazem reposição hormonal, OR = 0,05 (0,01-0,49). Já o nível de atividade física de intensidade moderada ofereceu proteção contra a gordura intra-abdominal independentemente da reposição hormonal ou dos períodos menstruais regulares, OR = 0,37 (0,14-0,66).CONCLUSÃO: A caminhada e principalmente o nível de atividade física de moderada intensidade podem ser importantes para prevenção do excesso de gordura intra-abdominal e suas complicações metabólicas e cardiovasculares em mulheres pós-menopaúsicas.

Effects of garcinia cambogia (Hydroxycitric Acid) on visceral fat accumulation: a double-blind, randomized, placebo-controlled trial

BACKGROUND

(-)-Hydroxycitric acid (HCA) is an active ingredient extracted from the rind of the Indian fruit Garcinia cambogia. It inhibits adenosine triphosphate citrate lyase and has been used in the treatment of obesity.

OBJECTIVE

The primary end point of this study was the effects of 12 weeks of G cambogia extract administration on visceral fat accumulation. The secondary end points were body indices (including height, body weight, body mass index [BMI], waist and hip circumference, and waist-hip ratio) and laboratory values (including total cholesterol, triacylglycerol, and free fatty acid).

METHODS

This study was performed according to a double-blind, randomized, placebo-controlled, parallel-group design. Subjects aged 20 to 65 years with a visceral fat area >90 cm(2) were enrolled. Subjects were randomly assigned to receive treatment for 12 weeks with G cambogia (containing 1000 mg of HCA per day) or placebo. At the end of the treatment period, both groups were administered placebo for 4 weeks to assess any rebound effect. Each subject underwent a computed tomography scan at the umbilical level at -2, 0, 12, and 16 weeks.

RESULTS

Forty-four subjects were randomized at baseline, and 39 completed the study (G cambogia group, n = 18; placebo group, n = 21). At 16 weeks, the G cambogia group had significantly reduced visceral, subcutaneous, and total fat areas compared with the placebo group (all indices P<0.001). No severe adverse effect was observed at any time in the test period. There were no significant differences in BMI or body weight at week 12, but there were slight numeric decreases in body weight and BMI in men. There were no signs of a rebound effect from week 12 to week 16.

CONCLUSION

G cambogia reduced abdominal fat accumulation in subjects, regardless of sex, who had the visceral fat accumulation type of obesity. No rebound effect was observed. It is therefore expected that G cambogia may be useful for the prevention and reduction of accumulation of visceral fat.

Interrelationships between changes in anthropometric variables and computed tomography indices of abdominal fat distribution in response to a 1-year physical activity–healthy eating lifestyle modification program in abdominally obese men

The objectives were to (i) measure the effects of a 1-year lifestyle modification program on body fat distribution/anthropometric variables; (ii) determine the interrelationships between changes in all these variables; and (iii) investigate whether there is a selective reduction in deep (DSAT) vs. superficial subcutaneous adipose tissue (SSAT) at the abdominal level following a 1-year lifestyle modification program. Anthropometric variables, body composition and abdominal and midthigh fat distribution were assessed at baseline and after 1 year in 109 sedentary, dyslipidemic and abdominally obese men. Reductions in anthropometric variables, skinfold thicknesses (except the trunk/extremity ratio) and fat mass as well as an increase in fat-free mass were observed after 1 year (p < 0.0001). Decreases in abdominal adipose tissue volumes were also noted (–23%, –26%, –18%, –19%, –17%, p < 0.0001 for total adipose tissue, visceral adipose tissue, subcutaneous adipose tissue, DSAT and SSAT, respectively). Adipose tissue areas at midthigh also decreased (–18%, –18%, –17%, p < 0.0001 for total, deep, and subcutaneous adipose tissue, respectively). A reduction (–9%, p < 0.0001) in low-attenuation muscle area and an increase (+1%, p < 0.05) in normal-attenuation muscle area were also observed. There was a positive relationship between changes in visceral adipose tissue and changes in DSAT (r = 0.65, p < 0.0001) or SSAT (r = 0.63, p < 0.0001). Although absolute changes in DSAT were greater than changes in SSAT, relative changes in both depots were similar, independent of changes in visceral adipose tissue. The 1-year lifestyle modification program therefore improved the body fat distribution pattern and midthigh muscle quality in abdominally obese men.

Visceral fat level is an independent risk factor for cardiovascular mortality in hemodialysis patients

BACKGROUND

Obesity is an independent risk factor for morbidity and mortality in cardiovascular diseases not only in the general population, but also in hemodialysis (HD) patients. We previously reported that an increased visceral fat area (VFA) determined using computed tomography (CT) scans was associated with atherosclerosis in HD patients. However, whether a high VFA is associated with increased cardiovascular mortality in HD patients remains unknown. Therefore, we investigated the relationship between VFA and prognosis in HD patients.

METHODS

VFA was estimated in 126 patients on maintenance HD using CT scans. These patients were followed for 60 months.

RESULTS

Kaplan-Meier analysis revealed that the cardiovascular survival rate was significantly lower in the high-VFA group, with a VFA of 71.5 cm(2) or greater, than in the low-VFA group, with a VFA of less than 71.5cm(2). In univariate Cox proportional hazards analyses, age, albumin, low-density lipoprotein cholesterol, cardio-thoracic ratio and VFA above 71.5 cm(2) were significantly correlated with cardiovascular deaths. In multivariate analyses testing these factors as dependent variables, VFA above 71.5 cm(2) was estimated to be an independent predictor of cardiovascular deaths.

CONCLUSION

These results suggest that an increased VFA is a stronger risk factor for cardiovascular deaths in HD patients. Measuring VFA may be recommended for predicting the risk of cardiovascular diseases in HD patients.

Validation of ultrasound examination for assessment of the abdominal visceral fat in clinically serious obese patient

BACKGROUND

Computerized tomography is the gold-standard for measurement of abdominal visceral fat. However, it is costly and involves submitting patients to ionizing radiation.

AIM

To validate the use of ultrasonography in assessing abdominal visceral fat among clinically serious obese patients of both genders.

METHODS

The sample included adult patients with clinically serious obesity with body mass index of 40 kg/m2 or from 35 kg/m(2) to 40 kg/m2 with co-morbidities. Abdominal visceral fat thickness was measured using ultrasound and tomography. Two ultrasonographic exams were conducted to assess the interobserver reproducibility among a patient subsample. Validation was done by comparing these results with the tomographic findings.

RESULTS

The study included 13 patients (61.54% female) with an average BMI of 38.82 kg/m2. In terms of validation, the result obtained from applying the Pearson correlation coefficient was equal to 0.94 (p = 0.0005), showing a strong positive correlation between the two measurements. As for the results for reproducibility, the interobserver was equal to 0.822, with a confidence interval of 95% (-0.076 to 0.980), revealing good interobserver agreement. The average difference between the two ultrasound interobserver examination was equal to 0.10 ± 1.51 (p=0.8898) and so not significant. Interobserver bias was also not significant.

CONCLUSION

The validation of ultrasonographic examination to replace tomographic method in assessing abdominal visceral fat among clinically serious obese patients was effective. The ultrasound measurement is independent of the examiner.

Relationship between dual-energy X-ray absorptiometry volumetric assessment and X-ray computed tomography-derived single-slice measurement of visceral fat

To reduce radiation exposure and cost, visceral adipose tissue (VAT) measurement on X-ray computed tomography (CT) has been limited to a single slice. Recently, the US Food and Drug Administration has approved a dual-energy X-ray absorptiometry (DXA) application validated against CT to measure VAT volume. The purpose of this study was to develop an algorithm to compute single-slice area values on DXA at 2 common landmarks, L2/3 and L4/5, from an automated volumetrically derived measurement of VAT. Volumetric CT and total body DXA were measured in 55 males (age: 21-77 yr; body mass index [BMI]: 21.1-37.9) and 60 females (age: 21-85 yr; BMI: 20.0-39.7). Equations were developed by applying the relationship of CT single-slice area and volume measurements of VAT to the DXA VAT volume measure as well as validating these against the CT single-slice measurements. Correlation coefficients between DXA estimate of single-slice area and CT were 0.94 for L2/3 and 0.96 for L4/5. The mean difference between DXA estimate of single-slice area and CT was 5 cm(2) at L2/3 and 3.8 cm(2) at L4/5. Bland-Altman analysis showed a fairly constant difference across the single-slice range in this study, and the 95% limits of agreement for the 2 methods were -44.6 to +54.6 cm(2) for L2/3 and -47.3 to +54.9 cm(2) for L4/5. In conclusion, a volumetric measurement of VAT by DXA can be used to estimate single-slice measurements at the L2/3 and the L4/5 landmarks.

Measurement of visceral fat by abdominal bioelectrical impedance analysis is beneficial in medical checkup

SUMMARY

OBJECTIVE

In addition to the waist circumference (WC) measurement, an accurate measurement of visceral fat is very important in terms of the pathology associated with the metabolic syndrome. The only method available for an accurate measurement of a visceral fat area (VFA) is abdominal computed tomography (CT). To overcome this limitation, we estimated VFA using abdominal bioelectrical impedance analysis (BIA) with accuracy comparable to that of abdominal CT, and investigated the relationship between VFA and risk factors of the metabolic syndrome. Because abdominal BIA detects excess visceral fat accumulation that cannot be detected by a measurement of WC, the characteristics of the subjects who were identified as having excessive visceral fat using BIA, but not WC, were examined.

METHODS

Abdominal BIA was used to estimate VFA in male subjects (n = 1803) (age: 48 ± 10 years, body mass index: 23.9 ± 3.0 kg/m(2)) who provided informed consent.

RESULTS

The prevalence of the metabolic syndrome diagnosed based on the diagnostic criteria established by the Japanese Society of Internal Medicine was 18%. Among the risk factors of the metabolic syndrome, WC was significantly correlated with triglycerides (TG), but estimated VFA was correlated with blood pressure and HDL-cholesterol (HDL-C), in addition to TG. Abdominal BIA detected excess visceral fat accumulation in 3% of subjects for whom WC had detected none. Elevated blood pressure, TG, and fasting plasma glucose and decreased HDL-C were also noted in these subjects, and the values of these risk factors were comparable to those of subjects in whom visceral fat accumulation was detected using WC.

CONCLUSION

Abdominal BIA is a simple and safe method that is superior to WC for the detection of excessive visceral fat accumulation. Therefore, abdominal BIA will likely be used clinically to detect excessive accumulation of visceral fat, which is an important predictor of the metabolic syndrome.

Is visceral fat really a coronary risk factor? A multi-detector computed tomography study

Metabolic syndrome (MS) is currently considered to be a risk factor for arteriosclerotic disease. The accumulation of visceral fat leads to arteriosclerotic disease after other risk factors have developed and either direct or mutual effects occur. The aim of this study was to verify whether visceral fat serves as an independent coronary risk factor. A total of 3157 patients who had undergone multi-detector computed tomography (MDCT) were analyzed via computed tomographic angiography and the measurement of their visceral fat area. Coronary arteries with > 70% stenosis were considered to be significant. The visceral fat area was measured at the umbilical level, and an area of 100 cm2 or more was defined as visceral obesity. Coronary risk factors (ie, hypertension, dyslipidemia, diabetes mellitus, family history, and smoking) were obtained from the patient medical records. The patients were divided into two groups: a visceral obesity group, 1130 patients (137.0 ± 31.1 cm2) and a nonvisceral obesity group, 2027 patients (57.3 ± 25.8 cm2). A significant difference in the incidence of coronary stenosis between the two groups was observed. According to multivariable analysis, the factors affecting coronary stenosis were age, gender, dyslipidemia, diabetes mellitus, and the ratio of visceral to subcutaneous fat. Visceral obesity was not found to be an independent coronary risk factor. Visceral obesity demonstrated the predominant presence of coronary risk factors.

Clinical utility and reproducibility of visceral adipose tissue measurements derived from dual-energy X-ray absorptiometry in White and African American adults

OBJECTIVE

The purpose of this study was to determine reproducibility and clinical thresholds for DXA-derived visceral adipose tissue (VAT).

DESIGN AND METHODS

The sample included 2317 white and African American adults 18-74 years of age. VAT areas (cm(2) ) were measured using a Hologic DXA scanner equipped with APEX 4.0 software. Reproducibility was assessed using repeated measurements on 101 participants scanned 14 days apart. Receiver Operating Characteristic (ROC) curves were used to assess clinical utility and select thresholds that identified elevated cardiometabolic risk, defined as the presence of ≥2 risk factors.

RESULTS

Reproducibility of DXA-VAT was 8.1%. The areas under the ROC curves ranged from 0.754 in African American men to 0.807 in white women. The thresholds were higher in white men (154 cm(2) ) and women (143 cm(2) ) compared to African American men (101 cm(2) ) and women (114 cm(2) ).

CONCLUSION

The results demonstrated that DXA VAT is a useful clinical marker of cardiometabolic risk; however, further research is required to determine associations with health outcomes using longitudinal studies.

Visceral adiposity in young patients with coronary artery disease-a case control study

AIMS

Central obesity is associated with an increased cardiovascular risk. We carried out a hospital based case control study in young patients with coronary artery disease (CAD) to assess the importance of visceral fat

METHODS

Coronary artery disease was established by coronary angiogram in all cases. Controls were age- and sex-matched subjects with normal coronary angiogram. Computed tomography scan performed at the level of the umbilicus to measure subcutaneous and visceral fat area (VFA).

RESULTS

Cases and controls were well matched in height, weight, and body mass index (BMI). Visceral fat area was significantly higher (122.58 ± 37.59 vs. 88.4 ± 36.95 cm(2); P=0.003) in cases whereas subcutaneous fat area was similar in cases and controls. Visceral fat area was an excellent predictor of cardiovascular risk (area under receiver operating characteristics curve 0.915 cm(2)). Visceral fat area correlated with BMI, waist hip ratio, blood sugar, triglycerides, and C-reactive protein significantly.

CONCLUSION

Visceral adiposity is associated with an increased risk of CAD and it correlated with anthropometric, metabolic, and inflammatory markers.

The visceral adiposity index as a predictor of insulin resistance in young women with polycystic ovary syndrome

OBJECTIVE

Visceral fat accumulation is more strongly related to insulin resistance than to excess total adiposity. The visceral adiposity index (VAI) has recently been suggested as an indicator of the visceral adiposity measured by magnetic resonance imaging. To evaluate whether the VAI could replace visceral computed tomography (CT) scanning and predict insulin resistance in young women with polycystic ovary syndrome (PCOS) was presented.

DESIGN AND METHODS

One hundred and eighty Korean women aged 16-41 years who were diagnosed with PCOS using the Rotterdam criteria were included. The VAI was derived from a formula using body mass index, waist circumference, triglycerides, and high-density lipoprotein cholesterol. Visceral adiposity was defined as a visceral fat area (VFA) measuring > 100 cm(2) by CT scanning. Insulin sensitivity was evaluated by insulin-mediated glucose utilization (M value), which was obtained using a euglycemic hyperinsulinemic clamp.

RESULTS

The VAI positively correlated with VFA, the visceral-to-subcutaneous fat ratio, and systolic and diastolic blood pressure, and negatively correlated with the M value. In a linear regression analysis, the VAI was an independent determinant of the insulin sensitivity after controlling for age, systolic blood pressure, fasting glucose, fasting insulin, and testosterone levels. In a logistic regression analysis, the VAI odds ratio was 3.5 (95% CI 1.2-9.8) for predicting visceral adiposity after controlling for the various metabolic parameters and testosterone.

CONCLUSION

The VAI can replace visceral CT scanning as a marker for visceral adiposity, and it predicts insulin resistance in young women with PCOS.

Effects of visceral fat area and other metabolic parameters on stone composition in patients undergoing percutaneous nephrolithotomy

PURPOSE

Obesity is a risk factor for metabolic syndrome and urolithiasis, particularly uric acid stones. As estimated by visceral fat area, visceral obesity is a more specific measure of the risk of metabolic syndrome than body mass index. We investigated the effects of visceral fat area and other metabolic factors on uric acid stone formation in patients treated with percutaneous nephrolithotomy.

MATERIALS AND METHODS

We retrospectively reviewed the records of 269 patients who underwent percutaneous nephrolithotomy. Visceral fat area was measured in each patient on a CT axial slice at the umbilical level using the Aquarius iNtuition fat analysis tool. Analysis was performed to determine the effect of visceral fat area and other comorbidities on uric acid stone formation.

RESULTS

Of the 269 patients analyzed there was no difference in baseline comorbidities between uric acid and nonuric acid stone formers. Patients with uric acid stones had a significantly higher mean visceral fat area (209.3 vs 161.9 cm², p = 0.001), and rates of hypertension (67.4% vs 47.3%) and coronary artery disease (14.3% vs 4.6%, each p = 0.011). On logistic regression analysis hypertension (OR 2.16, 95% CI 1.05-4.45, p = 0.04) and a high visceral fat area (OR 3.64, 95% CI 1.22-10.85, p = 0.02) were independent risk factors for uric acid stones.

CONCLUSIONS

As a marker of visceral obesity, visceral fat area contributes to the risk of metabolic syndrome and urolithiasis. Uric acid stone formers showed a significantly higher hypertension rate and mean visceral fat area, which were independent risk factors for uric acid urolithiasis. Evaluating these characteristics in stone formers may facilitate a tailored metabolic assessment and treatment plan.