Comparison of anthropometric, area- and volume-based assessment of abdominal subcutaneous and visceral adipose tissue volumes using multi-detector computed tomography

Association of fat density with subclinical atherosclerosis

Background

Ectopic fat density is associated with cardiovascular disease (CVD) risk factors above and beyond fat volume. Volumetric measures of ectopic fat have been associated with CVD risk factors and subclinical atherosclerosis. The aim of this study was to investigate the association between fat density and subclinical atherosclerosis.

Methods and Results

Participants were drawn from the Multi‐Detector Computed Tomography (MDCT) substudy of the Framingham Heart Study (n=3079; mean age, 50.1 years; 49.2% women). Fat density was indirectly estimated by computed tomography attenuation (Hounsfield Units [HU]) on abdominal scan slices. Visceral fat (VAT), subcutaneous fat (SAT), and pericardial fat HU and volumes were quantified using standard protocols; coronary and abdominal aortic calcium (CAC and AAC, respectively) were measured radiographically. Multivariable‐adjusted logistic regression models were used to evaluate the association between adipose tissue HU and the presence of CAC and AAC. Overall, 17.1% of the participants had elevated CAC (Agatston score [AS]>100), and 23.3% had elevated AAC (AS>age‐/sex‐specific cutoffs). Per 5‐unit decrement in VAT HU, the odds ratio (OR) for elevated CAC was 0.76 (95% confidence interval [CI], 0.65 to 0.89; P=0.0005), even after adjustment for body mass index or VAT volume. Results were similar for SAT HU. With decreasing VAT HU, we also observed an OR of 0.79 (95% CI, 0.67 to 0.92; P=0.004) for elevated AAC after multivariable adjustment. We found no significant associations between SAT HU and AAC. There was no significant association between pericardial fat HU and either CAC or AAC.

Conclusions

Lower VAT and SAT HU, indirect estimates of fat quality, are associated with a lower risk of subclinical atherosclerosis.

Sugar-sweetened beverage consumption is associated with abdominal fat partitioning in healthy adults

Abdominal adiposity, particularly visceral adipose tissue (VAT), is independently linked to the pathogenesis of diabetes and cardiovascular diseases. Emerging evidence suggests that greater intake of sugar-sweetened beverages (SSBs) may be associated with abnormal fat accumulation in VAT. We examined whether habitual SSB consumption and diet soda intakes are differentially associated with deposition of body fat. We conducted a cross-sectional analysis using previously collected data in 2596 middle-aged adults (1306 men and 1290 women) from the Framingham Heart Study Offspring and Third Generation cohorts. VAT and abdominal subcutaneous adipose tissue (SAT) were measured using multidetector computed tomography. Habitual intake of SSBs and diet soda was assessed by a validated food frequency questionnaire. We observed that SSB consumption was positively associated with VAT after adjustment for SAT and other potential confounders (P-trend < 0.001). We observed an inverse association between SSB consumption and SAT (P-trend = 0.04) that persisted after additional adjustment for VAT (P-trend < 0.001). Higher SSB consumption was positively associated with the VAT-to-SAT ratio (P-trend < 0.001). No significant association was found between diet soda consumption and either VAT or the VAT-to-SAT ratio, but diet soda was positively associated with SAT (P-trend < 0.001). Daily consumers of SSBs had a 10% higher absolute VAT volume and a 15% greater VAT-to-SAT ratio compared with nonconsumers, whereas consumption of diet soda was not associated with either volume or distribution of VAT.

Visceral adiposity is not associated with abdominal aortic aneurysm presence and growth

Previous studies in rodent models and patients suggest that visceral adipose could play a direct role in the development and progression of abdominal aortic aneurysm (AAA). This study aimed to assess the association of visceral adiposity with AAA presence and growth. This study was a case-control investigation of patients that did (n=196) and did not (n=181) have an AAA who presented to The Townsville Hospital vascular clinic between 2003 and 2012. Cases were patients with AAA (infra-renal aortic diameter >30 mm) and controls were patients with intermittent claudication but no AAA (infra-renal aortic diameter <30 mm). All patients underwent computed tomography angiography (CTA). The visceral to total abdominal adipose volume ratio was estimated from CTAs by assessing total and visceral adipose deposits using an imaging software program. Measurements were assessed for reproducibility by repeat assessments on 15 patients. AAA risk factors were recorded at entry. Forty-five cases underwent two CTAs more than 6 months apart to assess AAA expansion. The association of visceral adiposity with AAA presence and growth was examined using logistic regression. Visceral adipose assessment by CTA was highly reproducible (mean coefficient of variation 1.0%). AAA was positively associated with older age and negatively associated with diabetes. The visceral to total abdominal adipose volume ratio was not significantly associated with AAA after adjustment for other risk factors. Patients with a visceral to total abdominal adipose volume ratio in quartile four had a 1.63-fold increased risk of AAA but with wide confidence intervals (95% CI 0.71-3.70; p=0.248). Visceral adiposity was not associated with AAA growth. In conclusion, this study suggests that visceral adiposity is not specifically associated with AAA presence or growth although larger studies are required to confirm these findings.

Laparoscopy-assisted pylorus-preserving gastrectomy is better than laparoscopy-assisted distal gastrectomy for middle-third early gastric cancer

OBJECTIVE

The purpose of this study is to compare the surgical, oncologic safety and the nutritional, functional benefit of laparoscopy-assisted pylorus-preserving gastrectomy (LAPPG) with laparoscopy-assisted distal gastrectomy (LADG) for middle-third early gastric cancers (EGC).

BACKGROUND

Of those patients with middle-third EGC, it is still difficult to determine which procedure is better between LADG and LAPPG despite alleged advantages of LAPPG.

METHODS

For middle-third EGC, a retrospective analysis was performed comparing those who underwent LADG and those who underwent LAPPG. To evaluate surgical and oncologic safety, clinicopathologic differences including the postoperative morbidity, the pattern of lymph node metastasis and recurrence were analyzed. Postoperative protein, albumin, quantification of abdominal fat area using abdomen computed tomography, and the incidence of postoperative gallstone were compared for the evaluation of functional advantages.

RESULTS

The overall postoperative morbidity rate was similar between LADG (n = 176) and LAPPG (n = 116). Delayed gastric emptying was less frequent in LADG than in LAPPG (1.7% vs 7.8%); however, the rates of all the other complications were significantly higher in LADG than in LAPPG (17.0% vs 7.8%). The number of examined lymph nodes and metastatic lymph nodes at each lymph node station was not significantly different and 3-year recurrence-free survival rates were also similar between LADG and LAPPG (98.8% vs 98.2%). Decreases in serum protein and albumin in postoperative 1 to 6 months and abdominal fat area in postoperative 1 year were significantly greater in LADG than in LAPPG. The 3-year cumulative incidence of gallstone was significantly higher in LADG than in LAPPG (6.5% vs 0.0%).

CONCLUSIONS

For middle-third EGC, LAPPG can be considered as a better treatment option than LADG in terms of nutritional advantage and lower incidence of gallstone.

The impact of visceral obesity on surgical outcomes of laparoscopic surgery for colon cancer

PURPOSE

Although obesity is considered as a risk factor for postoperative morbidity in abdominal surgery, its effect on the outcomes of laparoscopic-assisted colectomy (LAC) is still unclear. The technical difficulty and risk factor for postoperative complication in LAC are thought to be influenced by visceral obesity. The aim of this prospective study was to evaluate the impact of visceral fat on the surgical outcomes of LAC.

METHODS

Between April 2005 and December 2010, consecutive patients with preoperatively diagnosed colon cancer, excluding medium and low rectal cancer, who underwent LAC, were enrolled. Their visceral fat area (VFA) and body mass index (BMI) were prospectively collected. The VFA was assessed by Fat Scan software. The patients were classified into two groups as follows: VFA nonobese with VFA <100 cm(2) (VNO) and VFA obese with VFA ≧100 cm(2) (VO). The predictive factors for surgical complications of LAC were evaluated by univariate and logistic regression analyses.

RESULTS

A total of 338 consecutive patients were enrolled in this study. Of the 338 patients, 194 (57.4 %) and 138 (42.6 %) were classified into the VNO and VO groups, respectively. Logistic regression analysis showed that high BMI (≧25 kg/m(2)) and VO independently predicted the incidence of overall postoperative complications (p = 0.040 and 0.007, respectively). VO was more highly related to the incidence of overall postoperative complications, anastomotic leakage (p = 0.021), and surgical site infection (SSI) (p = 0.013) than high BMI.

CONCLUSIONS

VFA is a more useful parameter than BMI in predicting surgical outcomes after LAC.

The association of visceral adiposity with cardiovascular events in patients with peripheral artery disease

BACKGROUND

Previous studies have suggested that patients with peripheral artery disease (PAD) suffer from a high incidence of cardiovascular events (CVE). Visceral adiposity has been implicated in promoting CVEs. This study aimed to assess the association of relative visceral adipose volume with incident cardiovascular events in patients with peripheral artery disease.

METHODS

This was a prospective cohort study including 260 patients with PAD who presented between 2003 and 2012. Cases were patients with diagnosed PAD including symptomatic lower limb athero-thrombosis and asymptomatic abdominal aortic aneurysm. All patients underwent computed tomography angiography (CTA). Abdominal visceral to total adipose volume ratio (relative visceral adipose volume) was estimated from CTAs using a previously validated workstation protocol. Cardiovascular risk factors were recorded at entry. The association of visceral adiposity with major CVEs (death, non-fatal myocardial infarction or stroke) was examined using Kaplan Meier and Cox proportional hazard analyses.

RESULTS

A total of 92 major CVEs were recorded in 76 patients during a median follow-up of 2.8 (IQR 1.2 to 4.8) years, including myocardial infarction (n = 26), stroke (n = 10) and death (n = 56). At 3 years the incidence of major CVEs stratified by relative visceral adipose volume quartiles were 15% [Quartile (Q) 1], 17% (Q2), 11% (Q3) and 15% (Q4) (P = 0.517). Relative visceral adipose volume was not associated with major CVEs after adjustment for other risk factors.

CONCLUSION

This study suggests that visceral adiposity does not play a central role in the predisposition for major CVEs in patients with PAD.

Accurate detection of metabolically active "brown" and "white" adipose tissues with computed tomography

BACKGROUND

Adipose tissues (AT) are highly metabolically active complex endocrine organs and are classified into white (WAT) and brown AT (BAT) with proinflammatory and anti-inflammatory characteristics. The current study investigated the accuracy of computed tomography (CT) to quantitatively detect BAT and WAT based on Hounsfield unit (HU) threshold compared to standardized uptake values (SUVs) of corresponding AT with the use of positron emission tomography (PET).

METHODS

One hundred twenty-four patients who underwent whole-body (18)F-fluorodeoxyglucose ((18)F-FDG) PET/CT were studied. The SUVs and HUs of regions of BAT and WAT were measured and compared in these scans. The receiver operator characteristic (ROC) analysis was used to detect the HU threshold values for the detection of BAT and WAT.

RESULTS

The CT HU of BAT, with high (18)F-FDG uptake, was significantly higher compared to WAT (-67.1 ± 8.2 [-10 to -87] versus -93.5 ± 10.1 [-88 to -190], P = .0006). Generalized linear-regression models revealed that mean CT HU of BAT was 26.4 HU higher than that of WAT (P = .001). A strong agreement between CT HU and PET SUV in measuring metabolically active AT (r(2) = 0.81, P = .0001) was observed. The ROC curve showed that the optimal cutoff value of CT HU to detect BAT was HU ≥-87 with sensitivity of 83.3% and specificity of 100%, and the negative CT HU below -87 is highly specific for WAT.

CONCLUSION

In our study, CT can accurately and quantitatively detect BAT and WAT based on CT HU threshold, which is -10 to -87 for BAT and -88 to -190 for WAT.

Depressive symptoms are associated with visceral adiposity in a community-based sample of middle-aged women and men

OBJECTIVE

To examine the relation between measures of adiposity and depressive symptoms in a large well characterized community-based sample, we examined the relations of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) to depressive symptoms in 1,581 women (mean age 52.2 years) and 1,718 men (mean age 49.8 years) in the Framingham Heart Study.

DESIGN AND METHODS

Depressive symptoms were measured using the Center for Epidemiologic Studies Depression (CES-D) scale. Regression models were created to examine the association between each fat depot (exposure) and depressive symptoms (outcome). Sex-specific models were adjusted for age, body mass index, smoking, alcohol consumption, diabetes, hypertension, total and HDL cholesterol, lipid lowering treatment, CVD, menopause, C-reactive protein, and physical activity.

RESULTS

Mean CES-D scores were 6.8 and 5.6 in women and men. High levels of depressive symptoms were present in 22.5% of women and 12.3% of men. In women, one standard deviation increase in VAT was associated with a 1.3 point higher CES-D score after adjusting for age and BMI (P < 0.01) and remained significant in the fully adjusted model (P = 0.03). The odds ratio of depressive symptoms per 1 standard deviation increase in VAT in women was 1.33 (P = 0.015); results were attenuated in fully adjusted models (OR 1.29, P = 0.055). In men, the association between VAT and CES-D score and depressive symptoms was not significant. SAT was not associated with CES-D score or depressive symptoms.

CONCLUSIONS

This study supports an association between VAT and depressive symptoms in women. Further work is needed to uncover the complex biologic mechanisms mediating the association.

Vegetarianism as a protective factor for reflux esophagitis: a retrospective, cross-sectional study between Buddhist priests and general population

BACKGROUND/AIMS

Several risk factors for reflux esophagitis, such as smoking, alcohol consumption, obesity, and metabolic syndrome, are recognized. But vegetarianism as a protective factor for reflux esophagitis has not been reported. The aim of this study is to elucidate the protective effect of vegetarianism for reflux esophagitis.

METHODS

This is a cross-sectional study that compared the prevalence of reflux esophagitis of 148 Buddhist priests, who are obligatory vegetarians with that of age- and sex-matched controls who underwent health checkups in a health promotion center.

RESULTS

The prevalence of reflux esophagitis was higher in the control group than in the Buddhist priest group (21.6 vs 12.2 %). Weight, body mass index, waist circumference, waist-to-hip ratio, and abdominal adipose tissue area were higher and high density lipoprotein (HDL) cholesterol and total cholesterol were lower in the Buddhist priest group. The prevalence of metabolic syndrome was higher in the Buddhist priest group than the control group (30.4 vs 17.6 %). In univariate analysis, male sex (odds ratio [OR] = 3.325; 95 % confidence interval [CI], 1.659-6.666), current smoking (OR = 3.37; 95 % CI, 1.439-7.881), alcohol consumption (OR = 2.75; 95 % CI, 1.375-5.481), waist circumference (OR = 1.99; 95 % CI, 1.062-3.739), negative for Helicobacter pylori IgG antibody (OR = 1.89; 95 % CI, 1.018-3.491) and non-vegetarianism (OR = 1.99; 95 % CI, 1.062-3.739) were associated with reflux esophagitis. According to multivariate analysis, male sex (OR = 3.44; 95 % CI, 1.698-6.970), non-vegetarianism (OR = 2.08; 95 % CI, 1.086-3.974) and negative H. pylori IgG antibody (OR = 1.96; 95 % CI, 1.039-3.712) were significantly associated with reflux esophagitis.

CONCLUSIONS

A non-vegetarian diet is associated with reflux esophagitis.

Impact of being overweight on the surgical outcomes of patients with gastric cancer: A meta-analysis

AIM: To investigate the effect of being overweight on the surgical results of patients with gastric cancer.

METHODS: Comprehensive electronic searches of the PubMed, Web of Science, and Cochrane Library databases were conducted. Studies were identified that included patients with surgical complications from gastric cancer who were classified as normal weight [body mass index (BMI) < 25 kg/m²] or overweight (BMI ≥ 25 kg/m²). The operative time, retrieved lymph nodes, blood loss, and long-term survival were analyzed. A subgroup analysis was conducted based on whether patients received laparoscopic or open gastrectomy procedures. All statistical tests were performed using ReviewerManager 5.1.2 software.

RESULTS: This meta-analysis included 23 studies with 20678 patients (15781 with BMI < 25 kg/m²; 4897 with BMI ≥ 25 kg/m²). Overweight patients had significantly increased operation times [MD: -29.14; 95%CI: -38.14-(-20.21); P < 0.00001], blood loss [MD: -194.58; 95%CI: -314.21-(-74.95); P = 0.001], complications (RR: 0.75; 95%CI: 0.66-0.85; P < 0.00001), anastomosis leakages (RR: 0.59; 95%CI: 0.42-0.82; P = 0.002), and pancreatic fistulas (RR: 0.486; 95%CI: 0.34-0.63; P < 0.00001), whereas lymph node retrieval was decreased significantly in the overweight group (MD: 1.69; 95%CI: 0.75-2.62; P < 0.0001). In addition, overweight patients had poorer long-term survival (RR: 1.14; 95%CI: 1.07-1.20; P < 0.0001). No significant difference was detected for the mortality and length of hospital stay.

CONCLUSION: This meta-analysis demonstrates that a high BMI not only increases the surgical difficulty and complications but also impairs the long-term survival of patients with gastric cancer.

Impact of being overweight on the surgical outcomes of patients with gastric cancer: A meta-analysis

AIM: To investigate the effect of being overweight on the surgical results of patients with gastric cancer.

METHODS: Comprehensive electronic searches of the PubMed, Web of Science, and Cochrane Library databases were conducted. Studies were identified that included patients with surgical complications from gastric cancer who were classified as normal weight [body mass index (BMI) < 25 kg/m²] or overweight (BMI ≥ 25 kg/m²). The operative time, retrieved lymph nodes, blood loss, and long-term survival were analyzed. A subgroup analysis was conducted based on whether patients received laparoscopic or open gastrectomy procedures. All statistical tests were performed using ReviewerManager 5.1.2 software.

RESULTS: This meta-analysis included 23 studies with 20678 patients (15781 with BMI < 25 kg/m²; 4897 with BMI ≥ 25 kg/m²). Overweight patients had significantly increased operation times [MD: -29.14; 95%CI: -38.14-(-20.21); P < 0.00001], blood loss [MD: -194.58; 95%CI: -314.21-(-74.95); P = 0.001], complications (RR: 0.75; 95%CI: 0.66-0.85; P < 0.00001), anastomosis leakages (RR: 0.59; 95%CI: 0.42-0.82; P = 0.002), and pancreatic fistulas (RR: 0.486; 95%CI: 0.34-0.63; P < 0.00001), whereas lymph node retrieval was decreased significantly in the overweight group (MD: 1.69; 95%CI: 0.75-2.62; P < 0.0001). In addition, overweight patients had poorer long-term survival (RR: 1.14; 95%CI: 1.07-1.20; P < 0.0001). No significant difference was detected for the mortality and length of hospital stay.

CONCLUSION: This meta-analysis demonstrates that a high BMI not only increases the surgical difficulty and complications but also impairs the long-term survival of patients with gastric cancer.

Visceral and subcutaneous fat quality and cardiometabolic risk

OBJECTIVES

The aim of this study was to evaluate whether computed tomography (CT) attenuation, as a measure of fat quality, is associated with cardiometabolic risk factors above and beyond fat quantity.

BACKGROUND

Visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) are pathogenic fat depots associated with cardiometabolic risk. Adipose tissue attenuation in CT images is variable, similar to adipose tissue volume. However, whether the quality of abdominal fat attenuation is associated with cardiometabolic risk independent of the quantity is uncertain.

METHODS

Participants were drawn from the Framingham Heart Study CT substudy. The VAT and SAT volumes were acquired by semiquantitative assessment. Fat quality was measured by CT attenuation and recorded as mean Hounsfield unit (HU) within each fat depot. Sex-specific linear and logistic multivariable regression models were used to assess the association between standard deviation (SD) decrease in HU and each risk factor.

RESULTS

Lower CT attenuation of VAT and SAT was correlated with higher body mass index levels in both sexes. Risk factors were generally more adverse with decreasing HU values. For example, in women, per 1 SD decrease in VAT HU, the odds ratio (OR) was increased for hypertension (OR: 1.80), impaired fasting glucose (OR: 2.10), metabolic syndrome (OR: 3.65), and insulin resistance (OR: 3.36; all p < 0.0001). In models that further adjusted for VAT volume, impaired fasting glucose, metabolic syndrome, and insulin resistance remained significant. Trends were similar but less pronounced for SAT and for men. There was evidence of an interaction between HU and fat volume among both women and men.

CONCLUSIONS

Lower CT attenuation of VAT and SAT is associated with adverse cardiometabolic risk above and beyond total adipose tissue volume. Qualitative indices of abdominal fat depots may provide insight regarding cardiometabolic risk independent of fat quantity.

Thoracic periaortic and visceral adipose tissue and their cross-sectional associations with measures of vascular function

OBJECTIVE

Perivascular fat may have a local adverse effect on the vasculature. We evaluated whether thoracic periaortic adipose tissue (TAT), a type of perivascular fat, and visceral adipose tissue (VAT) were associated with vascular function.

DESIGN AND METHODS

TAT and VAT were quantified in Framingham Heart Study participants using multidetector-computed tomography; vascular function was assessed using brachial artery vasodilator function, peripheral arterial tone, and arterial tonometry (n = 2,735; 48% women; mean age, 50 years; mean body mass index [BMI], 27.7 kg/m(2) ). Using multiple linear regression, the relationships between TAT, VAT, and vascular measures was examined while adjusting for cardiovascular risk factors.

RESULTS

Mean TAT and VAT volumes were 13.2 and 1763 cm(3) . TAT and VAT were associated with multiple vascular function measures after multivariable adjustment. After BMI adjustment, TAT and VAT remained negatively associated with peripheral arterial tone and inverse carotid femoral pulse wave velocity (P < 0.02); TAT was negatively associated with hyperemic mean flow velocity (P = 0.03). Associations of TAT with vascular function were attenuated after VAT adjustment (all P > 0.06).

CONCLUSIONS

Thoracic periaortic and visceral fat are associated with microvascular function and large artery stiffness after BMI adjustment. These findings support the growing recognition of associations between ectopic fat and vascular function.

Distribution, determinants, and normal reference values of thoracic and abdominal aortic diameters by computed tomography (from the Framingham Heart Study)

Current screening and detection of asymptomatic aortic aneurysms is based largely on uniform cut-point diameters. The aims of this study were to define normal aortic diameters in asymptomatic men and women in a community-based cohort and to determine the association between aortic diameters and traditional risk factors for cardiovascular disease. Measurements of the diameters of the ascending thoracic aorta (AA), descending thoracic aorta (DTA), infrarenal abdominal aorta (IRA), and lower abdominal aorta (LAA) were acquired from 3,431 Framingham Heart Study (FHS) participants. Mean diameters were stratified by gender, age, and body surface area. Univariate associations with risk factor levels were examined, and multivariate linear regression analysis was used to assess the significance of covariate-adjusted relations with aortic diameters. For men, the average diameters were 34.1 mm for the AA, 25.8 mm for the DTA, 19.3 mm for the IRA, and 18.7 mm for the LAA. For women, the average diameters were 31.9 mm for the AA, 23.1 mm for the DTA, 16.7 mm for the IRA, and 16.0 mm for the LAA. The mean aortic diameters were strongly correlated (p <0.0001) with age and body surface area in age-adjusted analyses, and these relations remained significant in multivariate regression analyses. Positive associations of diastolic blood pressure with AA and DTA diameters in both genders and pack-years of cigarette smoking with DTA diameter in women and IRA diameter in men and women were observed. In conclusion, average diameters of the thoracic and abdominal aorta by computed tomography are larger in men compared with women, vary significantly with age and body surface area, and are associated with modifiable cardiovascular disease risk factors, including diastolic blood pressure and cigarette smoking.

Aged garlic extract with supplement is associated with increase in brown adipose, decrease in white adipose tissue and predict lack of progression in coronary atherosclerosis

BACKGROUND

Aged garlic extract with supplement (AGE-S) significantly reduces coronary artery calcium (CAC). We evaluated the effects of AGE-S on change in white (wEAT) and brown (bEAT) epicardial adipose tissue, homocysteine and CAC.

METHODS

Sixty subjects, randomized to a daily capsule of placebo vs. AGE-S inclusive of aged garlic-extract (250 mg) plus vitamin-B12 (100 μg), folic-acid (300 μg), vitamin-B6 (12.5mg) and L-arginine (100mg) underwent CAC, wEAT and bEAT measurements at baseline and 12 months. The postcuff deflation temperature-rebound index of vascular function was assessed using a reactive-hyperemia procedure. Vascular dysfunction was defined according to the tertiles of temperature-rebound at 1 year of follow-up. CAC progression was defined as an annual-increase in CAC>15%.

RESULTS

From baseline to 12 months, there was a strong correlation between increase in wEAT and CAC (r(2)=0.54, p=0.0001). At 1 year, the risks of CAC progression and increased wEAT and homocysteine were significantly lower in AGE-S to placebo (p<0.05). Similarly, bEAT and temperature-rebound were significantly higher in AGE-S as compared to placebo (p<0.05). Strong association between increase in temperature-rebound and bEAT/wEAT ratio (r(2)=0.80, p=0.001) was noted, which was more robust in AGE-S. Maximum beneficial effect of AGE-S was noted with increase in bEAT/wEAT ratio, temperature-rebound, and lack of progression of homocysteine and CAC.

CONCLUSIONS

AGE-S is associated with increase in bEAT/wEAT ratio, reduction of homocysteine and lack of progression of CAC. Increases in bEAT/wEAT ratio correlated strongly with increases in vascular function measured by temperature-rebound and predicted a lack of CAC progression and plaque stabilization in response to AGE-S.

Intramuscular fat and associations with metabolic risk factors in the Framingham Heart Study

OBJECTIVE

Intramuscular fat accumulates between muscle fibers or within muscle cells. We investigated the association of intramuscular fat with other ectopic fat deposits and metabolic risk factors.

APPROACH AND RESULTS

Participants (n=2945; 50.2% women; mean age 50.8 years) from the Framingham Heart Study underwent multidetector computed tomography scanning of the abdomen. Regions of interest were placed on the left and right paraspinous muscle, and the muscle attenuation (MA) in Hounsfield units was averaged. We examined the association between MA and metabolic risk factors in multivariable models, and additionally adjusted for body mass index (BMI) and visceral adipose tissue (VAT) in separate models. MA was associated with dysglycemia, dyslipidemia, and hypertension in both sexes. In women, per standard deviation decrease in MA, there was a 1.34 (95% confidence interval, 1.10-1.64) increase in the odds of diabetes mellitus, a 1.40 (95% confidence interval, 1.22-1.61) increase in the odds of high triglycerides, and a 1.29 (95% confidence interval, 1.12-1.48) increase in the odds of hypertension. However, none of these associations persisted after adjustment for BMI or VAT. In men, we observed similar patterns for most risk factors. The exception was metabolic syndrome, which retained association in women even after adjustment for BMI and VAT, and low high density lipoprotein and high triglycerides in men, whose associations also persisted after adjustment for BMI and VAT.

CONCLUSIONS

MA was associated with metabolic risk factors, but most of these associations were lost after adjustment for BMI or VAT. However, a unique association remained for metabolic syndrome in women and lipids in men.

Visceral obesity and colorectal cancer: are we missing the boat with BMI?

INTRODUCTION

Compared to subcutaneous fat, visceral fat is more metabolically active, leading to chronic inflammation and tumorigenesis. The aim of this study is to describe the effect of visceral obesity on colorectal cancer outcomes using computed tomography (CT) imaging to measure visceral fat.

MATERIALS AND METHODS

We conducted a retrospective chart review of patients who underwent surgical resection for colorectal cancer. Visceral fat volume was measured by preoperative CT scans. Final analysis was performed by stratifying patients based on oncologic stage.

RESULTS

Two hundred nineteen patients met the inclusion criteria, 111 viscerally obese and 108 nonobese. Body mass index (BMI) weakly correlated with visceral fat volume measurements (R (2) = 0.304). Whereas obese patients had no difference in survival when categorizing obesity by BMI, categorizing based on visceral fat volume resulted in significant differences in stage II and stage III patients. In stage II cancer, viscerally obese patients had a nearly threefold decrease in disease-free survival (hazard ratio (HR) = 2.72; 95 % confidence interval (CI) = 1.21, 6.10). In stage III cancer, viscerally obese patients had a longer time to recurrence (HR = 0.39; 95 % CI = 0.16, 0.99).

CONCLUSION

This study shows that viscerally obese patients with stage II colorectal cancer are at higher risk for poor outcomes and should be increasingly considered for adjuvant chemotherapy.

Association of female reproductive factors with body composition: the Framingham Heart Study

BACKGROUND

Identifying reproductive risk factors in women offers a life course approach to obesity and cardiovascular disease prevention. The association of female reproductive factors with measures of regional body fat distribution has not been comprehensively studied.

METHODS

We examined the association of female reproductive factors (age at menarche, parity, age at natural menopause, menopausal status) in association with body composition data from women who participated in the Offspring and the Third Generation Framingham Heart Study cohorts. Visceral adipose tissue (VAT) and sc adipose tissue (SAT) were measured volumetrically by multidetector computerized tomography. We modeled the relationship between each fat depot and female reproductive factors after adjusting for various factors such as age, smoking status, alcohol intake, physical activity index, hormone replacement therapy, and menopausal status.

RESULTS

Earlier age at menarche was associated with increased body mass index (BMI), waist circumference (WC), VAT, and SAT (P < 0.0001). This association of earlier menarche with adiposity measures was attenuated after adjusting for BMI (all P > 0.70). We observed no association between parity and all parameters of adiposity measurements (all P > 0.24). Similarly, age at natural menopause was not associated with measures of body composition. Despite higher mean BMI among the post- (BMI 27.3 kg/m(2)) compared with the premenopausal women (BMI 25.9 kg/m(2)) in an age-matched analysis, mean VAT was not different between the two groups (P = 0.30).

CONCLUSIONS

Earlier menarche is associated with overall obesity but not with VAT or SAT after accounting for measures of generalized adiposity. Parity and menopausal age were not associated with adiposity measures. Although postmenopausal women had increased BMI, VAT, and SAT, the association was predominantly due to age.

Prevalence, distribution, and risk factor correlates of high thoracic periaortic fat in the Framingham Heart Study

Background

Thoracic periaortic adipose tissue (TAT) is associated with atherosclerosis and cardiovascular disease (CVD) risk factors and may play a role in obesity‐mediated vascular disease. We sought to determine the prevalence, distribution, and risk factor correlates of high TAT.

Methods and Results

Participants from the Framingham Heart Study (n=3246, 48% women, mean age 51.1 years) underwent multidetector computed tomography; high TAT and visceral adipose tissue (VAT) were defined on the basis of sex‐specific 90th percentiles in a healthy referent sample. The prevalence of high TAT was 38.1% in women and 35.7% in men. Among individuals without high VAT, 10.1% had high TAT. After adjustment for age and VAT, both women and men with high TAT in the absence of high VAT were older and had a higher prevalence of CVD (P<0.0001) compared with those without high TAT. In addition, men in this group were more likely to be smokers (P=0.02), whereas women were more likely to have low high‐density lipoprotein cholesterol (P=0.005).

Conclusions

Individuals in our community‐based sample with high TAT in the absence of high VAT were characterized by an adverse cardiometabolic profile. This adipose tissue phenotype may identify a subset of individuals with distinct metabolic characteristics.

Periaortic adipose tissue and aortic dimensions in the Framingham Heart Study

Background

Periaortic fat, because of its contiguity with the aorta, may promote vascular remodeling and aortic dilatation. However, the relations between perioartic fat depots and aortic dimensions have not been previously described.

Methods and Results

A total of 3001 individuals (mean age 50±10 years, 49% women) from the Framingham Offspring and Third Generation cohorts underwent computed tomography for quantification of periaortic fat and aortic dimensions. We estimated the association between quantitative periaortic and visceral adipose tissue volumes (per standard deviation [SD] increment of volume) with aortic dimensions in both the thorax and abdomen. Thoracic periaortic fat was associated with higher thoracic aortic dimensions (β coefficient per SD of fat volume 0.67 mm, 95% confidence interval 0.58 to 0.76 mm; P<0.001). The association persisted after adjustment for age, sex, and cardiovascular risk factors including body mass index and visceral adipose tissue volume. Results for the association of periaortic fat and abdominal aortic dimensions were similar. Further adjustment for adipokines (resistin and adiponectin) had no significant impact on these associations.

Conclusions

Periaortic fat volume was associated with aortic dimensions in both the thorax and abdomen, supporting the notion that local fat depots may contribute to aortic remodeling. Further work to understand the mechanisms underlying this association is warranted.

Effects of abdominal fat distribution parameters on severity of acute pancreatitis

BACKGROUND

Obesity is a well-established risk factor for acute pancreatitis. Increased visceral fat has been shown to exacerbate the pro-inflammatory milieu experienced by patients. This study aimed to investigate the relationship between the severity of acute pancreatitis and abdominal fat distribution parameters measured on computed tomography (CT) scan.

METHODS

Consecutive patients admitted to Cork University Hospital with acute pancreatitis between January 2005 and December 2010 were evaluated for inclusion in the study. An open source image analysis software (Osirix, v 3.9) was used to calculate individual abdominal fat distribution parameters from CT scans by segmentation of abdominal tissues.

RESULTS

A total of 214 patients were admitted with pancreatitis between January 2005 and December 2010. Sixty-two of these patients underwent a CT scan and were thus eligible for inclusion. Visceral fat volume was the volumetric fat parameter that had the most significant association with severe acute pancreatitis (P = 0.003). There was a significant association between visceral fat volume and subsequent development of systemic complications of severe acute pancreatitis (P = 0.003). There was a strong association between mortality and visceral fat volume (P = 0.019). Multivariate regression analysis, adjusted for gender, did not identify any individual abdominal fat distribution index as an independent risk factor for severe acute pancreatitis.

CONCLUSIONS

Overall, estimation of abdominal fat distribution parameters from CT scans performed on patients with acute pancreatitis indicates a strong association between visceral fat, severe acute pancreatitis, and the subsequent development of systemic complications. These data suggest that visceral fat volume should be incorporated into future predictive scoring systems.

The ratio of visceral to subcutaneous fat, a metric of body fat distribution, is a unique correlate of cardiometabolic risk

AIMS/HYPOTHESIS

The anatomic location of excess body fat has an impact on associated cardiometabolic morbidity, and visceral adipose tissue (VAT) is more pathogenic than subcutaneous adipose tissue (SAT). However, VAT or SAT alone provides little information regarding the relative distribution of body fat. We hypothesised that the propensity to store energy in VAT relative to SAT depots may be a correlate of cardiometabolic risk, and tested this hypothesis using the VAT/SAT ratio as a metric of fat distribution.

METHODS

We investigated associations of the VAT/SAT ratio with cardiometabolic traits in 3,223 participants (48% women) from the Framingham Heart Study. Fat depots were quantified by multidetector computed tomography (CT) scanning.

RESULTS

In women and men, higher VAT/SAT ratio was associated (p < 0.05) with most assessed cardiovascular risk factors reflecting blood pressure, dyslipidaemia and insulin resistance. Additional adjustment for BMI did not materially change the findings in women, and generally strengthened associations in men. Further adjustment for VAT attenuated some associations in women, but those with lower HDL-cholesterol, higher triacylglycerol (both p < 0.0001) and higher prevalence of hypertension (p = 0.02), diabetes (p = 0.01) and the metabolic syndrome (p = 0.005) remained significant. Similarly, in men, associations with higher systolic (p = 0.006) and diastolic blood pressure (p = 0.03), higher fasting glucose (p = 0.0005), lower HDL-cholesterol and higher triacylglycerol (both p < 0.0001) and higher prevalence of diabetes (p = 0.006) remained significant.

CONCLUSIONS/INTERPRETATION

VAT/SAT ratio is a correlate of cardiometabolic risk, above and beyond BMI and VAT. The propensity to store fat viscerally versus subcutaneously may be a unique risk factor independent of absolute fat volumes.

The effect of visceral fat mass on pancreatic fistula after pancreaticoduodenectomy

BACKGROUND

Obesity is associated with perioperative complications and has been considered a risk factor for surgical outcomes of patients undergoing abdominal surgery. The aim of this study is to evaluate the impact of the amount of visceral fat on postoperative morbidity of patients who underwent pancreaticoduodenectomy (PD).

METHODS

We reviewed 181 patients who underwent surgery for periampullary lesions at the Department of Surgery, Gangnam Severance Hospital, Yonsei University Health System between January 2003 and June 2010. The visceral fat area (VFA) and subcutaneous fat area were calculated by computed tomography software.

RESULTS

The mean body mass index (BMI) was 23.4 kg/m(2) (±3.1 kg/m(2)), and the mean VFA was 94.4 cm(2) (±49.5 cm(2)). The mean intraoperative blood loss, and the incidence of clinically relevant pancreatic fistula (grade B/C) and clinically relevant delayed gastric emptying (grade B/C) were significantly higher in the high-VFA group (≥100 cm(2)). In univariate analysis, the incidence of clinically relevant pancreatic fistula (grade B/C) was significantly higher in the high-BMI group (≥25 kg/m(2)), the high-VFA group(≥100 cm(2)), the large intraoperative blood loss and transfusion group, and in patients with pathology of nonpancreatic origin (ampulla, bile duct, or duodenum). In multivariate analysis, the high-VFA group (≥100 cm(2)) and patients with pathology of nonpancreatic origin were identified as independent factors for clinically relevant pancreatic fistula.

CONCLUSION

VFA is a better indicator for the development of pancreatic fistula after PD than BMI. High VFA (≥100 cm(2)) is a risk factor for developing a pancreatic fistula after PD.

Waist circumference in children and adolescents correlate with metabolic syndrome and fat deposits in young adults

BACKGROUND & AIMS

To determine the relevance of waist circumference (WC) measurement and monitoring in children and adolescents as an early indicator of overweight, metabolic syndrome (MS) and cardiovascular problems in young adults in comparison with visceral and subcutaneous adiposity.

METHODS

A cohort study with 159 subjects (51.6% female) started in 1999 with an average age of 13.2 years. In 1999, 2006 and 2008 weight, height, and WC were evaluated. In 2006 blood samples for laboratory diagnosis of MS were added. In 2008 abdominal computed tomography (ACT) to quantify the fat deposits were also added.

RESULTS

The WC measured in children and adolescents was strongly correlated with body mass index (BMI) measured simultaneously. A strong correlation was established between WC in 1999 with measures of WC and BMI as young adults. WC strongly correlated with fat deposits in ACT. The WC in 1999 expressed more subcutaneous fat (SAT), while the WC when young adults expressed strong correlation with both visceral fat (VAT) and SAT. The correlation of WC with fat deposits was stronger in females. WC and not BMI in 1999 was significantly higher in the group that evolved to MS.

CONCLUSIONS

The WC in children and adolescents was useful in screening patients for MS. WC expressed the accumulation of abdominal fat; especially subcutaneous fat.

Impact of visceral fat on laparoscopy-assisted distal gastrectomy

BACKGROUND

Obesity is known to be a preoperative risk factor for gastric cancer surgery. However, the influence of obesity on laparoscopy-assisted distal gastrectomy (LADG) remains controversial. In the present study, we evaluated several obesity parameters and investigated the influence of obesity on the surgical outcomes of LADG for gastric cancer.

MATERIALS AND METHODS

Between January 2010 and July 2011, 84 patients who underwent LADG for gastric cancer were enrolled. Visceral fat area (VFA) and subcutaneous fat area (SFA) were measured in cross-sectional CT scan using SlimVision(®) software. Patients were classified into two groups by the degree of BMI or VFA. Surgery time and blood loss were compared between each two groups. Predictive factors for perioperative complications were assessed by univariate and multivariate analyses.

RESULTS

There were no significant differences in surgery time or blood loss between patients with high and low BMIs. In contrast, high VFA patients had significantly longer surgery times (p=0.0047) and higher estimated blood loss (p=0.0034) than low VFA patients. By univariate and multivariate analyses, only a high VFA significantly predicted perioperative complications (p=0.0162, p=0.0288).

CONCLUSIONS

We suggest that VFA is more accurate than BMI in predicting surgery time, blood loss, and perioperative complications associated with LADG for gastric cancer. The visceral fat area could be efficiently assessed before laparoscopic surgery for gastric cancer in obese patients.

Cachexia but not obesity worsens the postoperative outcome after pancreatoduodenectomy in pancreatic cancer

BACKGROUND

Prognosis after pancreatoduodenectomy for pancreatic cancer is determined by tumor characteristics, completeness of resection, and patient's comorbidity. Our aim was to assess the effects of body mass and fat distribution on the postoperative course after pancreatoduodenectomy.

METHODS

Of 2,968 pancreatic resections, 408 patients with primary pancreatic adenocarcinoma who underwent pancreatoduodenectomy and of whom cross sectional images were available were identified and followed-up in a prospective database. Preoperative computed tomographic or magnetic resonance imaging scans were analyzed for abdominal wall fat, hip girdle fat, visceral fat, and abdominal depth. Peri- and postoperative parameters, including preoperative unintentional weight loss, cachexia-associated serum parameters, nonoperative and operative complications, and mortality and long-term survival were evaluated and correlated with body mass index and fat distribution.

RESULTS

Patients with low body mass index had a greater 90-day mortality (P = .048) and a trend toward greater complication rates and in-hospital mortality, despite a greater comorbidity in obese patients with a higher body mass index. Accordingly, patients with large amounts of abdominal wall fat had fewer intra-abdominal abscesses (P = .047), lower in-hospital (P = .019) and 90-day mortality rates (P = .007), and better long-term survival (P = .016).

CONCLUSION

In pancreatic cancer, underweight but not obese patients have a poor outcome after pancreatoduodenectomy. This observation emphasizes the need for pre- and perioperative therapeutic improvements in the setting of pancreatic cancer-associated cachexia.

A low level of serum total testosterone is independently associated with nonalcoholic fatty liver disease

BACKGROUND

The association between low serum testosterone levels, visceral adipose tissue (VAT), and metabolic syndrome is now well known. However, the relationship between hepatic steatosis and serum testosterone levels has not been extensively studied. Our aim was to investigate the association of serum total testosterone levels with nonalcoholic fatty liver disease (NAFLD), adjusting for the influence of VAT and insulin resistance.

METHODS

This study is a retrospective observational cross-sectional one of healthy Korean men and was conducted at the Seoul National University Hospital Healthcare System Gangnam Center. We used data obtained from 495 men who were at least 20 years of age and who had undergone blood testing, abdominal computed tomography, and ultrasonography. Multiple logistic regression analysis was used to explore the association of serum total testosterone levels with NAFLD.

RESULTS

Men in the low serum testosterone quintile were at a higher risk for NAFLD than men in the highest serum testosterone quintile. After adjusting for age, smoking, diabetes, exercise, BMI, triglycerides, and high-density-lipoprotein cholesterol, subjects with serum testosterone levels in the lowest quintile had an odds ratio (OR) (95% confidence interval (CI)) of 5.12 (2.43-10.77) for NAFLD (p value, 0.0004). The inverse association between serum testosterone and NAFLD was attenuated by further adjustment for variables including VAT; however, it remained statistically significant (OR (95% CI): 4.52 (2.09-9.80) in the lowest quintile; p value=0.004).

CONCLUSIONS

A low serum total testosterone level was independently associated with NAFLD. This report is the first one suggesting the association remains unchanged even after controlling for VAT and insulin resistance.

Dual-energy X-ray absorptiometry for quantification of visceral fat

Obesity is the major risk factor for metabolic syndrome and through it diabetes as well as cardiovascular disease. Visceral fat (VF) rather than subcutaneous fat (SF) is the major predictor of adverse events. Currently, the reference standard for measuring VF is abdominal X-ray computed tomography (CT) or magnetic resonance imaging (MRI), requiring highly used clinical equipment. Dual-energy X-ray absorptiometry (DXA) can accurately measure body composition with high-precision, low X-ray exposure, and short-scanning time. The purpose of this study was to validate a new fully automated method whereby abdominal VF can be measured by DXA. Furthermore, we explored the association between DXA-derived abdominal VF and several other indices for obesity: BMI, waist circumference, waist-to-hip ratio, and DXA-derived total abdominal fat (AF), and SF. We studied 124 adult men and women, aged 18-90 years, representing a wide range of BMI values (18.5-40 kg/m(2)) measured with both DXA and CT in a fasting state within a one hour interval. The coefficient of determination (r(2)) for regression of CT on DXA values was 0.959 for females, 0.949 for males, and 0.957 combined. The 95% confidence interval for r was 0.968 to 0.985 for the combined data. The 95% confidence interval for the mean of the differences between CT and DXA VF volume was -96.0 to -16.3 cm(3). Bland-Altman bias was +67 cm(3) for females and +43 cm(3) for males. The 95% limits of agreement were -339 to +472 cm(3) for females and -379 to +465 cm(3) for males. Combined, the bias was +56 cm(3) with 95% limits of agreement of -355 to +468 cm(3). The correlations between DXA-derived VF and BMI, waist circumference, waist-to-hip ratio, and DXA-derived AF and SF ranged from poor to modest. We conclude that DXA can measure abdominal VF precisely in both men and women. This simple noninvasive method with virtually no radiation can therefore be used to measure VF in individual patients and help define diabetes and cardiovascular risk.

Genome-wide association for abdominal subcutaneous and visceral adipose reveals a novel locus for visceral fat in women

Body fat distribution, particularly centralized obesity, is associated with metabolic risk above and beyond total adiposity. We performed genome-wide association of abdominal adipose depots quantified using computed tomography (CT) to uncover novel loci for body fat distribution among participants of European ancestry. Subcutaneous and visceral fat were quantified in 5,560 women and 4,997 men from 4 population-based studies. Genome-wide genotyping was performed using standard arrays and imputed to ~2.5 million Hapmap SNPs. Each study performed a genome-wide association analysis of subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), VAT adjusted for body mass index, and VAT/SAT ratio (a metric of the propensity to store fat viscerally as compared to subcutaneously) in the overall sample and in women and men separately. A weighted z-score meta-analysis was conducted. For the VAT/SAT ratio, our most significant p-value was rs11118316 at LYPLAL1 gene (p = 3.1 × 10E-09), previously identified in association with waist-hip ratio. For SAT, the most significant SNP was in the FTO gene (p = 5.9 × 10E-08). Given the known gender differences in body fat distribution, we performed sex-specific analyses. Our most significant finding was for VAT in women, rs1659258 near THNSL2 (p = 1.6 × 10-08), but not men (p = 0.75). Validation of this SNP in the GIANT consortium data demonstrated a similar sex-specific pattern, with observed significance in women (p = 0.006) but not men (p = 0.24) for BMI and waist circumference (p = 0.04 [women], p = 0.49 [men]). Finally, we interrogated our data for the 14 recently published loci for body fat distribution (measured by waist-hip ratio adjusted for BMI); associations were observed at 7 of these loci. In contrast, we observed associations at only 7/32 loci previously identified in association with BMI; the majority of overlap was observed with SAT. Genome-wide association for visceral and subcutaneous fat revealed a SNP for VAT in women. More refined phenotypes for body composition and fat distribution can detect new loci not previously uncovered in large-scale GWAS of anthropometric traits.

Genome-wide association of pericardial fat identifies a unique locus for ectopic fat

Pericardial fat is a localized fat depot associated with coronary artery calcium and myocardial infarction. We hypothesized that genetic loci would be associated with pericardial fat independent of other body fat depots. Pericardial fat was quantified in 5,487 individuals of European ancestry from the Framingham Heart Study (FHS) and the Multi-Ethnic Study of Atherosclerosis (MESA). Genotyping was performed using standard arrays and imputed to ∼2.5 million Hapmap SNPs. Each study performed a genome-wide association analysis of pericardial fat adjusted for age, sex, weight, and height. A weighted z-score meta-analysis was conducted, and validation was obtained in an additional 3,602 multi-ethnic individuals from the MESA study. We identified a genome-wide significant signal in our primary meta-analysis at rs10198628 near TRIB2 (MAF 0.49, p = 2.7×10^-08). This SNP was not associated with visceral fat (p = 0.17) or body mass index (p = 0.38), although we observed direction-consistent, nominal significance with visceral fat adjusted for BMI (p = 0.01) in the Framingham Heart Study. Our findings were robust among African ancestry (n = 1,442, p = 0.001), Hispanic (n = 1,399, p = 0.004), and Chinese (n = 761, p = 0.007) participants from the MESA study, with a combined p-value of 5.4E-14. We observed TRIB2 gene expression in the pericardial fat of mice. rs10198628 near TRIB2 is associated with pericardial fat but not measures of generalized or visceral adiposity, reinforcing the concept that there are unique genetic underpinnings to ectopic fat distribution.

Pericardial fat is a localized fat depot associated with coronary artery calcium and myocardial infarction. To test whether genetic loci are associated with pericardial fat independent of other body fat depots, we measured pericardial fat in 5,487 individuals of European ancestry. After performing an unbiased screen using genome-wide association, we identified a genome-wide significant signal in our primary meta-analysis at rs10198628 near TRIB2 (MAF 0.49, p = 2.7×10^-08). This SNP was not associated with visceral fat (p = 0.17) or body mass index (p = 0.38). Our findings were robust among multi-ethnic participants from the MESA study, with a combined p-value of 5.4E-14. We observed TRIB2 gene expression in the pericardial fat of mice. rs10198628 near TRIB2 is associated with pericardial fat but not measures of generalized or visceral adiposity, reinforcing the concept that there are unique genetic underpinnings to ectopic fat distribution.

Inverse association between brown adipose tissue activation and white adipose tissue accumulation in successfully treated pediatric malignancy

BACKGROUND

Although the accumulation of white adipose tissue (WAT) is a risk factor for disease, brown adipose tissue (BAT) has been suggested to have a protective role against obesity.

OBJECTIVE

We studied whether changes in BAT were related to changes in the amounts of subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) in children treated for malignancy.

DESIGN

We examined the effect of BAT activity on weight, SAT, and VAT in 32 pediatric patients with cancer whose positron emission tomography-computed tomography (PET-CT) scans at diagnosis showed no BAT activity. Changes in weight, SAT, and VAT from diagnosis to remission for children with metabolically active BAT at disease-free follow-up (BAT+) were compared with those in children without visualized BAT when free of disease (BAT-).

RESULTS

Follow-up PET-CT studies (4.7 ± 2.4 mo later) after successful treatment of the cancer showed BAT+ in 19 patients but no active BAT (BAT-) in 13 patients. BAT+ patients, in comparison with BAT- patients, gained significantly less weight (3.3 ± 6.6% compared with 11.0 ± 11.6%; P = 0.02) and had significantly less SAT (18.2 ± 26.5% compared with 67.4 ± 71.7%; P = 0.01) and VAT (22.6 ± 33.5% compared with 131.6 ± 171.8%; P = 0.01) during treatment. Multiple regression analysis indicated that the inverse relations between BAT activation and measures of weight, SAT, and VAT persisted even after age, glucocorticoid treatment, and the season when the PET-CT scans were obtained were accounted for.

CONCLUSION

The activation of BAT in pediatric patients undergoing treatment of malignancy is associated with significantly less adipose accumulation. This trial was registered at clinicaltrials.gov as NCT01517581.

Correlation of renin angiotensin and aldosterone system activity with subcutaneous and visceral adiposity: the framingham heart study

BACKGROUND

Animal studies suggest that local adipocyte-mediated activity of the renin-angiotensin-aldosterone system (RAAS) contributes to circulating levels, and may promote the development of obesity-related hypertension in rodents.

METHODS

We examined relations of systemic RAAS activity, as assessed by circulating plasma renin activity (PRA), serum aldosterone level, and aldosterone:renin ratio (ARR), with specific regional adiposity measures in a large, community-based sample. Third Generation Framingham Heart Study participants underwent multidetector computed tomography assessment of SAT and VAT volumes during Exam 1 (2002 and 2005). PRA and serum aldosterone were measured after approximately 10 minutes of supine rest; results were log-transformed for analysis. Correlation coefficients between log-transformed RAAS measures and adiposity measurements were calculated, adjusted for age and sex. Partial correlations between log-transformed RAAS measures and adiposity measurements were also calculated, adjusted for standard CVD risk factors.

RESULTS

Overall, 992 women and 897 men were analyzed (mean age 40 years; 7% hypertension; 3% diabetes). No associations were observed with SAT (renin r = 0.04, p = 0.1; aldosterone r = -0.01, p = 0.6) or VAT (renin r = 0.03, p = 0.2; aldosterone r = -0.03, p = 0.2). Similar results were observed for ARR, in sex-stratified analyses, and for BMI and waist circumference. Non-significant partial correlations were also observed in models adjusted for standard cardiovascular risk factors.

CONCLUSIONS

Regional adiposity measures were not associated with circulating measures of RAAS activity in this large population-based study. Further studies are required to determine whether adipocyte-derived RAAS components contribute to systemic RAAS activity in humans.

Relation of vascular growth factors with CT-derived measures of body fat distribution: the Framingham Heart Study

BACKGROUND

Visceral adiposity is associated with metabolic risk. Given that angiogenesis is a key feature of adipogenesis, variation in the association of levels of circulating vascular growth factors (and their soluble receptors) with distinct body fat compartments may explain differences in the systemic pathogenicity of regional fat depots.

METHODS AND RESULTS

Four body fat compartments [visceral adipose tissue (VAT), sc adipose tissue (SAT), thoracic periaortic fat, and pericardial fat] derived from computed tomography were related to serum concentrations of vascular endothelial growth factor (VEGF), the soluble VEGF receptor (fms-like tyrosine kinase-1), hepatocyte growth factor (HGF), and angiopoietin-2 and its soluble receptor (soluble tyrosine kinase with immunoglobulin-like and EGF-like domains 2 sTie-2) in 1806 Framingham Heart Study participants (mean age 44.9 yr, 44.5% women). In multivariable models, we observed positive associations between several fat compartments and VEGF and HGF levels. The magnitude of the associations were similar for VAT, SAT, and periaortic fat. We observed effect modification by sex. A stronger association was observed between VAT and HGF levels in women; higher VAT and periaortic fat were jointly associated with higher HGF concentrations (P=0.02 and P=0.051, respectively). In women within the highest tertile of VAT, HGF levels significantly increased with higher periaortic fat (P=0.0005).

CONCLUSIONS

In our large community-based sample, greater adiposity was associated with higher circulating growth factor levels in general. Additional studies are warranted to confirm the stronger association of VAT and periaortic fat with HGF in women and to examine its potential contribution to the sex-related differences in cardiometabolic risk.

Development and reproducibility of a computed tomography-based measurement of renal sinus fat

Background

Renal sinus fat may mediate obesity-related vascular disease, although this fat depot has not been assessed in a community-based sample. We sought to develop a protocol to quantify renal sinus fat accumulation using multi-detector computed tomography (MDCT).

Methods

Protocol development was performed in participants in the Framingham Offspring cohort who underwent MDCT. Volumetric renal sinus fat was measured separately within the right and left kidneys, and renal sinus fat area within a single MDCT scan slice was measured in the right kidney. Due to the high correlation of volumetric and single-slice renal sinus fat in the right kidney (Pearson correlation [r] = 0.85, p < 0.0001), we optimized a single-slice protocol to capture renal sinus fat in the right kidney alone. Pearson correlation coefficients were used to compare to assess the correlation of volumetric and single-slice renal sinus fat in the right kidney with other measures of adiposity. Inter- and intra-reader reproducibility was assessed using intra-class correlation coefficients.

Results

Single-slice measurements were obtained in 92 participants (mean age 60 years, 49% women, median renal sinus fat 0.43 cm²). Intra- and inter-reader intra-class correlation coefficients were 0.93 and 0.86, respectively. Single-slice renal sinus fat was correlated with body mass index (r = 0.35, p = 0.0006), waist circumference (r = 0.31, p = 0.003), and abdominal visceral fat (r = 0.48, p < 0.0001). Similar correlations were observed for volumetric renal sinus fat in the right kidney.

Conclusions

Measuring renal sinus fat is feasible and reproducible using MDCT scans in a community-based sample.

Relation of visceral adiposity to circulating natriuretic peptides in ambulatory individuals

Natriuretic peptides have important roles in the regulation of vasomotor tone, salt homeostasis, and ventricular remodeling. Lower natriuretic peptide levels observed in obese individuals may underlie the greater cardiovascular risk associated with obesity. Thus the aim of this study was to determine whether lower natriuretic peptide levels in obesity are attributable to differences in regional fat distribution. We investigated the relation of plasma N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) to regional adiposity in 1,873 community-based individuals (46% women, mean age 45 years). Subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) volumes were measured by multidetector computed tomography. In gender-specific multivariable analyses adjusting for age and blood pressure, log NT-pro-BNP was inversely associated with VAT in men (beta -0.11 per standard deviation increment, p <0.001) and women (beta -0.19, p <0.001). Log NT-pro-BNP was inversely associated with SAT in women only (beta -0.14, p <0.001). In models containing VAT and SAT, only VAT was significantly associated with log NT-pro-BNP (men, beta -0.137, p <0.001; women, beta -0.184, p <0.001). VAT remained associated with log NT-pro-BNP even after adjustment for body mass index and waist circumference (beta -0.119, p <0.001) and in analyses restricted to nonobese patients (beta -0.165, p <0.001). Adjustment for insulin resistance attenuated the associations of NT-pro-BNP with VAT and SAT. In conclusion, this study demonstrates that circulating NT-pro-BNP is related to variations in regional and particularly visceral adiposity. These findings suggest that excess visceral adiposity and concomitant hyperinsulinemia may contribute to the natriuretic peptide "deficiency" observed in obesity.

[Identification and quantification of fat compartments with CT and MRI and their importance]

In addition to being overweight, as defined by the BMI, the distribution, composition and biological activity of adipose tissue are key elements in the cardiovascular risk stratification of patients. Several non-invasive techniques have been developed to quantify local fat depots, whereby computed tomography (CT) and magnetic resonance imaging (MRI) are the most important. In general adipose tissue is subdivided into subcutaneous and visceral compartments and although both are associated with cardiovascular risk factors and disease, visceral fat has on average a stronger association and a clearly higher biological activity independent of traditional risk factors. This maybe explained by the higher endocrine activity and secretion of pro-inflammatory cytokines by visceral fat. Especially pericardial adipose tissue, a local visceral fat depot surrounding the coronary arteries, is associated with the presence, extent and severity of coronary artery disease. However, several other local fat depots have been identified and associations with various diseases have been established. This article gives an overview over the current methods for the identification and quantification of local fat depots and summarizes the hypothesized and known associations. Furthermore, it gives an overview of the potential significance of individual local fat depots for cardiovascular risk stratification.

Influence of pericoronary adipose tissue on local coronary atherosclerosis as assessed by a novel MDCT volumetric method

OBJECTIVE

Pericoronary adipose tissue (PCAT) may create a pro-inflammatory state, contributing to the development of coronary artery disease (CAD). We sought to evaluate the feasibility of a novel volumetric PCAT quantification method using a novel threshold based computed tomography approach. In addition we determined the relation between PCAT volumes and CAD.

METHODS

In 51 patients (49.5±5.1 years, 64.8% male) who underwent 64-slice MDCT, we measured threshold-based PCAT volumes using distance and anatomic-based methods. Using the most reproducible method, we performed the proximal 40-mm distance measurement in three groups as stratified by coronary plaque and high-sensitivity C-reactive protein (hs-CRP) levels: Group 1 (presence of coronary plaque, hs-CRP >2.0 mg/L); an intermediate group (Group 2, no plaque, hs-CRP >2.0 mg/L); and Group 3 (no plaque, hs-CRP<1.0 mg/L). We compared PCAT volumes to the presence of coronary plaque on a patient (n=51) and vessel (n=153) basis. On a subsegment basis (n=1224), we compared PCAT volume to the presence of plaque as well as plaque morphology.

RESULTS

Distance-based PCAT volume measurements yielded excellent reproducibility with intra-observer intraclass correlation (ICC) of 0.997 and inter-observer ICC of 0.951. On a both a per-patient and per-vessel analysis, adjusted PCAT volume was greater in patients with plaque (Group 1) than without plaque (Groups 2 and 3, p<0.001). No difference in PCAT volume was seen between high and low hs-CRP groups without plaque (p=0.51). Adjusted PCAT volumes were higher in subsegments with plaque as compared without (p<0.001). Additionally, adjusted PCAT volume was greatest in subsegments with mixed plaque followed by non-calcified plaque, calcified plaque, and the lowest volume in segments with no plaque (p<0.001).

CONCLUSION

In this proof-of-concept study, threshold based PCAT volume assessment is feasible and highly reproducible. PCAT volume is increased in patients and vessels with coronary plaques. Surrounding vessel subsegments with coronary plaque, particularly mixed plaques, have greatest PCAT volume and highlight the effect of local PCAT in the development of coronary atherosclerosis.

Computed tomographic evaluation of abdominal fat in minipigs

Computed tomography (CT) exams were conducted to determine the distribution of abdominal fat identified based on the CT number measured in Hounsfield Units (HU) and to measure the volume of the abdominal visceral and subcutaneous fat in minipigs. The relationship between the CT-based fat volumes of several vertebral levels and the entire abdomen and anthropometric data including the sagittal abdominal diameter and waist circumference were evaluated. Moreover, the total fat volumes at the T11, T13, L3, and L5 levels were compared with the total fat volume of the entire abdomen to define the landmark of abdominal fat distribution. Using a single-detector CT, six 6-month-old male minipigs were scanned under general anesthesia. Three radiologists then assessed the HU value of visceral and subcutaneous abdominal fat by drawing the region of interest manually at the T11, T13, L1, L3, and L5 levels. The CT number and abdominal fat determined in this way by the three radiologists was found to be correlated (intra-class coefficient = 0.9). The overall HU ranges for the visceral and subcutaneous fat depots were -147.47 to -83.46 and -131.62 to -90.97, respectively. The total fat volume of the entire abdomen was highly correlated with the volume of abdominal fat at the T13 level (r = 0.97, p < 0.0001). These findings demonstrate that the volume of abdominal adipose tissue measured at the T13 level using CT is a strong and reliable predictor of total abdominal adipose volume.

Visceral abdominal adipose tissue and coronary atherosclerosis in asymptomatic diabetics

BACKGROUND

Visceral abdominal adipose tissue (VAT) may play an active role in the progression of coronary atherosclerosis. We examined the relation between VAT, non-alcoholic fatty liver disease and extent of coronary atheroma in patients with type 2 diabetes mellitus but no known coronary artery disease.

METHODS

Coronary artery calcium and area, distribution and thickness of upper abdominal fat were measured in selected axial cross-sections from non-enhanced computed tomography (CT) scans of the chest. Coronary atheroma was assessed visually on a per vessel basis from 64 slice CT angiography using axial views and multi-format reconstructions. Fatty liver was diagnosed when liver density was <40 Hounsfield units (HU) or ≥10 HU below spleen density.

RESULTS

The area of VAT was increased in patients with versus without multi-vessel coronary artery plaque (237.0 ± 101.4 vs 179.2 ± 79.4 mm(2), p<0.001). Waist circumference (101.6 ± 12.3 versus 95.3 ± 13.8 cm) and internal abdominal diameter (218.7 ± 33.0 vs 194.6 ± 25.7 mm) (both p<0.001) were increased in patients with multi-vessel plaque whereas subcutaneous fat was unrelated to coronary plaque. Presence of fatty liver (93/318 patients, 29.2%) did not correlate with presence or extent of coronary plaque. The correlation of VAT with multi-vessel plaque although nominally independent of the metabolic syndrome (p=0.04) was not independent of waist circumference.

CONCLUSION

In asymptomatic subjects with DM and no history of CAD area of VAT correlated with the presence and extent of coronary atheroma but as a risk predictor added little independent information to that obtained by more readily obtainable measures of adiposity-waist circumference and internal abdominal diameter.

Association of subcutaneous and visceral adiposity with albuminuria: the Framingham Heart Study

Microalbuminuria is a common condition associated with increased incidence of cardiovascular events and mortality. Abdominal obesity is associated with microalbuminuria, but studies linking visceral adipose tissue (VAT) and microalbuminuria are limited. Our objective was to determine the associations of albuminuria with VAT and subcutaneous adipose tissue (SAT). We performed a cross-sectional study in the Framingham Multi-Detector Computed Tomography (MDCT) cohort (n = 3099, 48.2% women, mean age 53 years). VAT and SAT volumes were measured using computed tomography. Urinary albumin-to-creatinine ratio (UACR) was calculated from spot urine samples. Microalbuminuria was defined as a UACR >25 mg/g in women or >17 mg/g in men. Overall, 7.9% (n = 244) of the sample had microalbuminuria. Among men, VAT (odds ratio (OR) 1.48 per s.d., P < 0.0001) and SAT (OR 1.37 per s.d., P = 0.0002) were associated with microalbuminuria in minimally adjusted models, which remained significant after multivariable adjustment (VAT OR 1.34 per s.d., P = 0.001; SAT OR 1.28 per s.d., P = 0.005). Additionally, when considered jointly, VAT (P = 0.002) but not SAT (P = 0.2) was associated with microalbuminuria. In women, VAT was associated with microalbuminuria after minimal adjustment (OR 1.28, P = 0.01), but not after multivariable adjustment (OR 1.03, P = 0.8). In multivariable models in women, SAT was associated with a decreased odds of having microalbuminuria (OR 0.75 per s.d., P = 0.03). In conclusion, VAT is associated with microalbuminuria in men but not women. Albuminuria may be a manifestation of visceral adiposity.

Computed tomography volumetric fat parameters versus body mass index for predicting short-term outcomes of colon surgery

BACKGROUND

At present, the impact of obesity on short-term outcomes of general surgery remains controversial, especially in the field of laparoscopy. Most studies on the subject have used the body mass index (BMI) to define obesity without distinguishing between visceral and subcutaneous storage. Computed tomography (CT) volumetric analysis permits accurate evaluation of site-specific volume of adipose tissue. The purpose of this study was to compare CT volumetric fat parameters and the BMI for predicting short-term outcomes of colon surgery.

METHODS

A retrospective analysis was conducted of 231 consecutive patients undergoing elective colon resection, with open or laparoscopic technique, from January 2007 to April 2009. CT volumetric quantification of abdominal visceral and subcutaneous adipose tissue was performed. Intraoperative and perioperative data were collected.

RESULTS

A total of 187 patients were enrolled. BMI showed a direct correlation with fat volumetric parameters but not with the visceral/subcutaneous fat ratio. Operating time was correlated with subcutaneous fat storage and BMI in the laparoscopic right colectomy subgroup. No associations were found with the conversion rate. Length of the hospital stay was correlated with the visceral/subcutaneous fat ratio in the laparoscopic left colectomy subgroup. Whereas the overall postoperative complication rate and mortality were not associated with fat parameters, the postoperative surgical complication rate was associated with visceral volumetric parameters in the laparoscopic left colectomy subgroup.

CONCLUSIONS

Short-term outcomes of colon surgery are better predicted by fat volumetric parameters than by the BMI. This study has provided new elements for discussion on the impact of visceral and subcutaneous adiposity in laparoscopic and traditional colon surgery.

Functional brown adipose tissue is related to muscle volume in children and adolescents

OBJECTIVE

We examined whether the depiction of brown adipose tissue (BAT) with positron emission tomography/computed tomography (PET/CT) in pediatric patients is associated with anthropometric measures.

STUDY DESIGN

We determined measures of body mass, adiposity, and musculature in 71 children and adolescents who underwent PET/CT examinations and compared patients with and without BAT. We used regression analyses to assess the relation between BAT and anthropometric measures.

RESULTS

A total of 30 patients (42%) had BAT depicted on PET/CT, 10 of 26 girls (38%) and 20 of 45 boys (44%). Compared with patients without functional BAT, patients with BAT had significantly greater neck musculature (1880 ± 908 cm(3) versus 1299 ± 806 cm(3); P = .028 for boys and 1295 ± 586 cm(3) versus 854 ± 392 cm(3); P = .030 for girls) and gluteus musculature (1359 ± 373 cm(3) versus 1061 ± 500 cm(3); P = .032 for boys and 1138 ± 425 cm(3) versus 827 ± 297 cm(3); P = .038 for girls), but no differences in age, body mass index, or measures of subcutaneous fat. With logistic regression analyses, neck and pelvic musculature predicted the presence of BAT independently of age, sex, body size, and season of scan (P = .018 and .009, respectively).

CONCLUSION

Pediatric patients with visualized BAT on PET/CT examinations had significantly greater muscle volume than patients with no visualized BAT.

[Whole-body MRI in the study of health in Pomerania]

Population-based whole-body MRI examinations have been evaluated for the first time within the Study of Health in Pomerania (SHIP). This ongoing cohort study investigates associations of overweight (57.9% of the female and 74.1% of the male population) and obesity (25.1% and 26.0%, respectively) with cardiovascular and metabolic diseases in a population with decreased life expectancy compared to the total German average. Whole-body MRI offers the possibility to evaluate parameters, such as the amount of visceral and liver fat and can contribute to further conclusions on these common diseases.

Appendicitis, Body Mass Index, and CT: Is CT More Valuable for Obese Patients than Thin Patients?

The purpose of our study is to determine whether body mass index (BMI = weight in kg/height in meters2) was related to the rate of negative appendectomy in patients who underwent preoperative CT. A surgical database search performed using the procedure code for appendectomy identified 925 patients at least 18 years of age who underwent urgent appendectomy between January 1998 and September 2007. BMI was computed for the 703 of these 925 patients for whom height and weight information was available. Patients were stratified based on body mass index (BMI 15-18.49 = underweight; 18.5-24.9 = normal weight; 25–29.9 = overweight; 30-39.9 = obese; > 40 = morbidly obese). Negative appendectomy rates were computed. Negative appendectomy rates for patients who did and did not undergo preoperative CT were 27 per cent and 50 per cent for underweight patients, 10 per cent and 15 per cent for normal weight patients, 12 per cent and 17 per cent for overweight patients, 7 per cent and 30 per cent for obese patients, and 10 per cent and 100 per cent for morbidly obese patients. The difference in negative appendectomy rates for overweight patients, obese patients, and morbidly obese patients who underwent preoperative CT as compared with patients in the same BMI category who did not undergo preoperative CT was statistically significant ( P ≤ 0.001). The negative appendectomy rates for overweight patients, obese patients, and morbidly obese patients who underwent preoperative CT were significantly lower than for patients in these same BMI categories who did not undergo preoperative CT.

Age-related changes in abdominal fat distribution in Japanese adults in the general population

OBJECTIVE

Early studies have indicated that body fat shifts from peripheral stores to central stores with aging. The objective of this study was to investigate age-related changes in abdominal fat distribution of Japanese men and women of the general population over a wide range of body mass indices (BMI).

METHODS

A total of 2,220 non-diabetic, apparently healthy Japanese adults (1,240 men and 980 women; age range 40-69 years) were included in the study sample. All subjects underwent a CT scan at the level of the umbilicus, and the areas of visceral adipose tissue (AT) and subcutaneous AT were quantified.

RESULTS

When the subjects were stratified by BMI into 18.5-23.0 kg/m(2), 23.0-27.5 kg/m(2), and 27.5 kg/m(2) or higher, visceral AT was positively correlated with age in all of the BMI strata in both genders (p<0.01). In contrast, subcutaneous AT was negatively correlated with age in men with BMIs in excess of 23.0 kg/m(2) (p<0.01) and not at all in women. The mean levels of subcutaneous AT were over 2-fold greater than visceral AT in women aged 60-69 years in any BMI stratum.

CONCLUSION

In Japanese men and women, visceral AT was increased with age in all BMI strata in both genders, whereas subcutaneous AT was decreased with age in men with BMIs in excess of 23.0 kg/m(2) and not at all in women. Even with these age-related changes in abdominal fat distribution, women retained the subcutaneous-dominant type of fat distribution up to 70 years.

Perivascular adipose tissue and vascular disease

Perivascular adipose tissue is a local deposit of adipose tissue surrounding the vasculature. Perivascular adipose tissue is present throughout the body and has been shown to have a local effect on blood vessels. The influence of perivascular adipose tissue on the vasculature changes with increasing adiposity. This article describes the anatomy and pathophysiology of perivascular adipose tissue and the experimental evidence supporting its local adverse effect on the vasculature. Methods for quantifying perivascular adipose tissue in free-living populations will be described. Finally, the epidemiological literature demonstrating an association between perivascular adipose tissue and cardiometabolic disease will be explored.

Epicardial fat: an additional measurement for subclinical atherosclerosis and cardiovascular risk stratification?

BACKGROUND

The value of epicardial adipose tissue (EAT) thickness as determined by echocardiography in cardiovascular risk assessment is not well understood. The aim of this study was to determine the associations between EAT thickness and Framingham risk score, carotid intima media thickness, carotid artery plaque, and computed tomographic coronary calcium score in a primary prevention population.

METHODS

Patients presenting for cardiovascular preventive care (n = 356) who underwent echocardiography as well as carotid artery ultrasound and/or coronary calcium scoring were included.

RESULTS

EAT thickness was weakly correlated with Framingham risk score. The prevalence of carotid plaque was significantly greater in those with EAT thickness ≥ 5.0 mm who either had low Framingham risk scores or had body mass indexes ≥ 25 kg/m(2), compared with those with EAT thickness <5.0 mm. No significant association between EAT thickness and carotid intima-media thickness or coronary calcium score existed.

CONCLUSION

EAT thickness ≥ 5.0 mm may identify an individual with a higher likelihood of having detectable carotid atherosclerosis.

Assessment of feline abdominal adipose tissue using computed tomography

Obesity is a common nutritional disorder in cats and it increases the risk factors for various diseases. The aim of this study is to suggest a method for the evaluation of feline obesity using computed tomography. The attenuation range from -156 to -106 was determined as the range of feline abdominal adipose tissue. With this range, total (TAT), visceral (VAT) and subcutaneous (SAT) adipose tissues were measured. The best correlation between the adipose tissue in cross-sectional image and entire abdomen volume was obtained at the L3 and L5 levels. The mean VAT/SAT ratio was 1.18±0.32, which was much higher than in humans. The cats with an overweight body condition had a significantly lower VAT/SAT ratio than cats with an ideal body condition. This technique may contribute to both the clinical diagnosis and the experimental study of feline obesity.