A novel method of measuring intra-abdominal fat volume using helical computed tomography

An Evaluation of Renal Sinus Fat Accumulation Using the Anteroposterior Diameter of the Renal Sinus on a Computed Tomography Axial Image

Backgrounds and objectives Renal sinus fat (RSF) is an indicator of obesity-related complications. However, the measurement and imaging process are complicated. For a simple measurement of RSF, we focused on the kidney's shape change caused by RSF accumulation. Thus, this study aimed to investigate whether the anteroposterior diameter of the renal sinus (APDRS) on a computed tomography (CT) axial image is useful for evaluating RSF accumulation. Materials and methods The correlation between APDRS and RSF was investigated in 98 outpatients who underwent abdominal CT. In addition, the correlation between APDRS or RSF and obesity indicators (estimated glomerular filtration rate from serum creatinine levels (eGFRcreat), body mass index (BMI), and visceral adipose tissue (VAT)) was also investigated. We classified patients based on the presence or absence of at least one underlying disease (chronic kidney disease (CKD), cardiovascular diseases (CVD), hypertension, and type 2 diabetes (T2D)) and investigated significant differences between the two groups at APDRS and RSF. The intraclass correlation coefficient (ICC) was also calculated for APDRS. Results There was a strong positive correlation between RSF and APDRS (r = 0.802, P < 0.01). The obesity indicators (eGFRcreat, BMI, and VAT) were correlated with RSF and APDRS (P < 0.01). Out of 98 outpatients, 48 had at least one underlying disease. There were statistically significant differences in APDRS and RSF between the patients with and without at least one of the underlying diseases caused by obesity (P < 0.01). The inter-reader ICC for the measurement of the APDRS was 0.98. Conclusions APDRS on a CT axial image may be useful for the evaluation of RSF accumulation.

Association of Anthropometric and CT-Based Obesity Indices with Subclinical Atherosclerosis

AIM

Few studies have compared the strength in the associations of anthropometric and computed tomography (CT)-based obesity indices with coronary artery calcification (CAC), aortic artery calcification (AoAC), and aortic valve calcification (AVC).

METHODS

We assessed cross-sectcional associations of anthropometric and CT-based obesity indices with CAC, AoAC, and AVC. Anthropometric measures included body mass index (BMI), waist circumference, hip ircumference, waist-to-hip circumference ratio, and waist-to-height ratio in 931 men (mean age, 63.7 years) from a population-based cohort. CT images at the L4/5 level were obtained to calculate the areas of abdominal visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), total adipose tissue (TAT), VAT-to-SAT ratio (VSR), and VAT-to-TAT ratio (VTR). CAC, AoAC, and AVC were quantified using the Agatston score based on CT scanning.

RESULTS

CAC, AVC, and AoAC were present in 348 (62.6%), 173 (18.6%), and 769 (82.6%) participants, respectively. In multivariable models adjusting for age, lifestyle factors, and CT types (electron beam CT and multidetector row CT), anthropometric and CT-based obesity indices were positively associated with CAC (p＜0.01). Conversely, VAT-to-SAT ratio and VAT-to-TAT ratio were positively associated with AoAC (p＜0.01). Any obesity indices were not associated with AVC.

CONCLUSIONS

The strength of the associations of obesity indices with subclinical atherosclerosis varied according to the anatomically distinct atherosclerotic lesions, among men.

Impact of Sex-Specific Preoperative Fat Mass Assessment on Long-Term Prognosis after Gastrectomy for Gastric Cancer

We investigated the impact of the difference in fat distribution between men and women on long-term prognosis after gastrectomy in patients with advanced gastric cancer. Patients with advanced gastric cancer deeper than p-T2 who underwent gastrectomy between April 2008 and June 2018 were included. Visceral fat mass index (VFI) and subcutaneous fat mass index (SFI) were calculated by dividing the cross-sectional area at the umbilical level by the height squared. The medians of VFI and SFI by sex were defined as cut-off values, below which values were defined as low VFI and low SFI. Of the 485 patients, 323 (66.6%) were men and 162 (33.4%) were women. Men with a low VFI had a significantly worse overall survival (OS) (p = 0.004) and women with a low SFI had a significantly worse OS (p = 0.007). Patients with a low VFI and low SFI had the worst prognosis. Multivariate analysis showed that a low VFI was an independent poor prognostic factor in men, while a low SFI was an independent poor prognostic factor in women. In conclusion, a low visceral fat mass in men and a low subcutaneous fat mass in women were independent poor prognostic factors after radical gastrectomy for advanced gastric cancer.

Conditioned Media from Head and Neck Cancer Cell Lines and Serum Samples from Head and Neck Cancer Patients Drive Catabolic Pathways in Cultured Muscle Cells

BACKGROUND

The role of secreted factors from the tumor cells in driving cancer cachexia and especially muscle loss is unknown. We wanted to study both the action of secreted factors from head and neck cancer (HNC) cell lines and circulating factors in HNC patients on skeletal muscle protein catabolism.

METHODS

Conditioned media (CM) made from head and neck cancer cell lines and mix of sera from head and neck cancer (HNC) patients were incubated for 48 h with human myotubes. The atrophy and the catabolic pathway were monitored in myotubes. The patients were classified regarding their skeletal muscle loss observed at the outset of management.

RESULTS

Tumor CM (TCM) was able to produce atrophy on myotubes as compared with control CM (CCM). However, a mix of sera from HNC patients was not able to produce atrophy in myotubes. Despite this discrepancy on atrophy, we observed a similar regulation of the catabolic pathways by the tumor-conditioned media and mix of sera from cancer patients. The catabolic response after incubation with the mix of sera seemed to depend on the muscle loss seen in patients.

CONCLUSION

This study found evidence that the atrophy observed in HNC patients cannot be solely explained by a deficit in food intake.

Automated volume measurement of abdominal adipose tissue from entire abdominal cavity in Dixon MR images using deep learning

The purpose of this study was to realize an automated volume measurement of abdominal adipose tissue from the entire abdominal cavity in Dixon magnetic resonance (MR) images using deep learning. Our algorithm involves a combination of extraction of the abdominal cavity and body trunk regions using deep learning and extraction of a fat region based on automatic thresholding. To evaluate the proposed method, we calculated the Dice coefficient (DC) between the extracted regions using deep learning and labeled images. We also compared the visceral adipose tissue (VAT) and subcutaneous adipose tissue volumes calculated by employing the proposed method with those calculated from computed tomography (CT) images scanned on the same day using the automatic calculation method previously developed by our group. We implemented our method as a plug-in in a web-based medical image processing platform. The DCs of the abdominal cavity and body trunk regions were 0.952 ± 0.014 and 0.995 ± 0.002, respectively. The VAT volume measured from MR images using the proposed method was almost equivalent to that measured from CT images. The time required for our plug-in to process the test set was 118.9 ± 28.0 s. Using our proposed method, the VAT volume measured from MR images can be an alternative to that measured from CT images.

Effect of malnutrition as defined by the Global Leadership Initiative on Malnutrition criteria on compliance of adjuvant chemotherapy and relapse-free survival for advanced gastric cancer

OBJECTIVES

The aim of the present study was to clarify the effect of malnutrition as defined by the Global Leadership Initiative on Malnutrition (GLIM) criteria on compliance with postoperative adjuvant chemotherapy and relapse-free survival (RFS) in patients with gastric cancer.

METHODS

This single-center, retrospective cohort study included 281 consecutive patients with gastric cancer who underwent radical gastrectomy for pathologic stages II and III and received postoperative S-1 adjuvant chemotherapy between April 2008 and June 2018. Treatment failure was defined as discontinuation of adjuvant chemotherapy ≤1 y. Nutritional assessment was preoperatively performed according to the GLIM criteria for all patients. We analyzed risk factors for treatment failure and poor prognostic factors for RFS using multivariate analyses.

RESULTS

Treatment failure and recurrence were observed in 50 (17.8%) and 97 (34.5%) of the 281 patients, respectively. The median follow-up period was 52 mo. The treatment failure rate was higher (P = 0.032) and RFS was worse (P = 0.017) in the malnutrition group. In multivariate analyses, GLIM criteria-defined malnutrition was an independent risk factor for treatment failure (odds ratio = 3.110; 95% confidence interval [CI], 1.020-9.470; P = 0.046). Furthermore, severe malnutrition was an independent poor prognostic factor for RFS (hazard ratio = 1.767; 95% CI, 1.132-2.759; P = 0.012).

CONCLUSIONS

Preoperative malnutrition as defined by the GLIM criteria was an independent risk factor for poor compliance with adjuvant S-1 chemotherapy and a poor prognostic factor for RFS after radical gastrectomy in patients with advanced gastric cancer. <END ABSTRACT>.

A simple and reproducible measure of adipose depots with non-contrast post-mortem computed tomography

Background and aim

Obesity is associated with an increase in different adipose depots. The anatomic distribution of internal adipose confers different risks. Recently, significant interest has emerged in the expansion of epicardial adipose tissue (EAT) as a mediator of adverse cardiovascular events. Often, post-mortem examination remains the best method of investigating morphological changes in health and disease. This study aimed to develop a simple, reproducible, and non-invasive protocol for the measurement of internal adiposity using post-mortem computed tomography (PMCT).

Patients and methods

101 consecutive post-mortem subjects underwent non-contrast computed tomography scans. Measurements were performed using the open-source software 3D Slicer by a non-expert researcher. An expert radiologist and cardiologist verified the abdominal and cardiac sites of adiposity, respectively. We aimed to develop a protocol to measure total EAT, sub-depots of EAT, extra-pericardial adipose, visceral and subcutaneous adipose, and suprasternal adipose.

Results

We found excellent reproducibility for our measures of total EAT, anterior right atrial EAT, extra-pericardial adipose, and visceral adipose tissue, with intraclass correlations between 0.82 and 0.99 for each measure. Due to a lack of suitable anatomical boundaries, other sub-depots of EAT, including in the interventricular groove, were not reproducible.

Conclusions

Quantification of total EAT and anterior right atrial EAT are readily reproducible using 3D Slicer on post-mortem CT. They can be reliably measured by non-expert researchers with a small amount of training, and therefore be used to investigate morphological changes in adiposity in health and disease.

Preoperative High Visceral Fat Increases Severe Complications but Improves Long-Term Prognosis after Gastrectomy for Patients with Advanced Gastric Cancer: A Propensity Score Matching Analysis

This study investigated the paradox of high visceral fat mass increasing severe complications but improving long-term prognosis after radical gastrectomy for gastric cancer. This was a retrospective cohort study of consecutive patients with primary stage I–III gastric cancer who underwent gastrectomy between April 2008 and June 2018. The visceral adipose tissue index (VAI) was calculated by dividing the visceral fat mass preoperatively measured on computed tomography by the square of the height. Patients with VAIs below the median cut-off value were classified as low-VAI, while those above it were classified as high-VAI. We compared the postoperative complication rate and overall survival (OS) in the low- and high-VAI groups after adjusting patient characteristics using propensity score matching (PSM). There were 155 patients in both groups after PSM. After matching, there was no significant difference in factors other than BMI and VAI that were not adjusted. The high-VAI group had more severe postoperative complications (p = 0.018), but the OS was significantly better in the high-VAI group (hazard ratio 0.611, 95%CI 0.403–0.928, p = 0.021). Preoperative high visceral fat mass not only increased severe complications, but also improved OS after gastrectomy in patients with advanced gastric cancer.

Effect of High-Intensity Interval Training Combined with Blood Flow Restriction at Different Phases on Abdominal Visceral Fat among Obese Adults: A Randomized Controlled Trial

BACKGROUND

High-intensity interval training (HIIT) and blood flow restriction (BFR) represent a critical nonpharmacological strategy to reduce the excess deposition of visceral fat, as well as relevant complications, among obese populations. Applying BFR at diverse phases may have different effects. Therefore, the exercise program of this study combined HIIT with BFR, so as to explore the effect of BFR on abdominal visceral fat area and its mechanism in different periods of HIIT. The aim is to provide a more effective exercise prescription for obese people who want to reduce visceral fat quickly.

METHODS

This study was a randomized controlled trial involving 72 obese adults. One week before intervention, both regional and whole-body fat masses, abdominal subcutaneous and visceral fat areas, variables of blood metabolism, and VO_2max were recorded. Additionally, subjects with a matched fat percentage were randomized as a no-training control (C), HIIT (H), HIIT with BFR during interval (I), and HIIT with BFR during exercise (E) groups for 24 sessions within a 12-week period, using a cycle ergometer. During session one, this study recorded blood lactate, specific serum lipolytic hormones, rating of perceived exertion (RPE), and exercise heart rate (HR) and compared them among three groups. The baseline tests were repeated at 1 week after intervention.

RESULTS

There was no significant statistical difference in the indicators of each group at baseline (p > 0.05). The improvement of trunk fat mass and fat percentage of the I and E groups markedly increased relative to the H group (p < 0.05). Meanwhile, the I group had improved android fat mass and whole-body fat mass relative to group H (p < 0.05). Those exercise groups had markedly improved indices compared with the C group (p < 0.05). Additionally, the reduction in the I group had remarkably superior abdominal visceral fat areas (AVFA) to the H and E groups (p < 0.05). Immediately and 30 min following exercise, the E and I groups had remarkably increased growth hormone (GH) compared with the H group (p < 0.05). After exercise, the I group showed markedly increased epinephrine (EPI) compared with the H group (p < 0.05). The LA level in the I group evidently increased relative to the E group (p < 0.05), while that in the E group evidently increased compared with the H group (p < 0.05).

CONCLUSION

Compared with HIIT alone, HIIT with BFR can better improve the body-fat level and glucose metabolism. HIIT with BFR in the interval phase better reduces the abdominal visceral-fat level than in the exercise phase, which may be due to the increase in lipolytic hormone level caused by the higher physiological load.

A low subcutaneous fat mass is a risk factor for the development of inguinal hernia after radical prostatectomy

PURPOSE

Inguinal hernia (IH) after radical prostatectomy (RP) is a complication that impairs quality of life; however, the factors contributing to IH after RP remain unclear. Therefore, we herein attempted to identify the factors responsible for the development of IH after RP.

METHODS

We reviewed 622 patients who underwent laparoscopic or robot-assisted laparoscopic RP at our hospital between December 2011 and April 2020. The total fat area and visceral fat area were calculated at the level of the umbilicus using computed tomography, and the subcutaneous fat area (SFA) was calculated by subtracting the visceral fat area from the total fat area. The psoas muscle area was measured at the third lumbar vertebrae level using computed tomography to calculate the psoas muscle mass index, which is used in sarcopenia as an index of muscle mass. We investigated the risk factors for IH after laparoscopic or robot-assisted laparoscopic RP.

RESULTS

IH developed in 88 patients (16.7%). Fifty-seven of these patients underwent hernia repair at our hospital, and 56 (98.2%) had indirect hernias. A multivariate analysis identified SFA (odds ratios: 0.383, p < 0.001) as an independent predictor for the development of IH. Two-year IH-free survival rates were 77.3% in the small SFA group (SFA < 123 cm²) and 88.7% in the large SFA group (SFA ≥ 123 cm²) (p < 0.001).

CONCLUSION

Subcutaneous fat was associated with the development of IH, particularly indirect IH, after laparoscopic or robot-assisted laparoscopic RP. An indirect IH prevention technique needs to be considered, particularly for patients with less subcutaneous fat.

Evaluation of the Value of Waist Circumference and Metabolomics in the Estimation of Visceral Adipose Tissue

Visceral adipose tissue (VAT) is a strong prognostic factor for cardiovascular disease and a potential target for cardiovascular risk stratification. Because VAT is difficult to measure in clinical practice, we estimated prediction models with predictors routinely measured in general practice and VAT as outcome using ridge regression in 2,501 middle-aged participants from the Netherlands Epidemiology of Obesity study, 2008-2012. Adding waist circumference and other anthropometric measurements on top of the routinely measured variables improved the optimism-adjusted R2 from 0.50 to 0.58 with a decrease in the root-mean-square error (RMSE) from 45.6 to 41.5 cm2 and with overall good calibration. Further addition of predominantly lipoprotein-related metabolites from the Nightingale platform did not improve the optimism-corrected R2 and RMSE. The models were externally validated in 370 participants from the Prospective Investigation of Vasculature in Uppsala Seniors (PIVUS, 2006-2009) and 1,901 participants from the Multi-Ethnic Study of Atherosclerosis (MESA, 2000-2007). Performance was comparable to the development setting in PIVUS (R2 = 0.63, RMSE = 42.4 cm2, calibration slope = 0.94) but lower in MESA (R2 = 0.44, RMSE = 60.7 cm2, calibration slope = 0.75). Our findings indicate that the estimation of VAT with routine clinical measurements can be substantially improved by incorporating waist circumference but not by metabolite measurements.

HELICAL COMPUTERIZED TOMOGRAPHY CAN MEASURE SUBCUTANEOUS, VISCERAL AND TOTAL FAT AREAS?

Background:

Abdominal obesity or android obesity, that is, the increase in adipose tissue in the abdominal region, is considered a risk factor for several morbidities. Different ways of quantifying it have been proposed, one method is the measurement of the abdominal fat area by computed tomography.

Aim:

To establish correspondence between the groups defined by degree of obesity in relation to the total, subcutaneous and visceral fat area.

Methods:

Cross-sectional observational study carried out through the analysis of tomographic examinations. Horos v3.3.5 medical image visualization software was used, with abdominal tomography in a single cut including the L4 vertebral body and the umbilical scar, to obtain the areas of total, visceral and subcutaneous fat.

Results:

Of the 40 patients, 10 had grade II obesity, 23 grade III and 7 superobese. The amount of total fat showed an increase in relation to the degree of obesity. Visceral fat did not show significant differences between the degrees of obesity, but the data showed a lower average in the group of obesity grade II. The area of subcutaneous fat, as well as total fat, showed an increase in its measurements, according to the progression of the patients’ BMI, but there was no statistical significance in this difference between the groups of grade II and super-obese individuals.

Conclusion:

The area of total and subcutaneous fat showed an increase in its measurements according to the progression of the BMI groups, which did not happen with visceral fat.

Computed Tomography and Magnetic Resonance Correlation and Agreement for Foot Muscle and Adipose Tissue Measurements

BACKGROUND

Volumetric measures of intrinsic foot muscle and intermuscular adipose tissue (IMAT) infiltration are important in understanding foot injury and disease. We questioned whether measures of muscle and fat derived from computed tomography (CT) and magnetic resonance (MR) would be comparable.

METHODS

This study determined the correlation and level of agreement between CT and MR measurements of foot muscle and IMAT from 32 subjects with diabetes and peripheral neuropathy. Volumetric CT and DIXON 3T MR scans were obtained. Intermuscular adipose tissue and muscle volumes used to create the IMAT to muscle ratio were obtained by segmenting the forefoot muscle compartment from each modality.

RESULTS

Computed tomography IMAT ratios were significantly correlated (r = 0.85, P < 0.0001) with MR IMAT ratios. Computed tomography and MR IMAT ratio mean difference between CT and MR was small (0.044 unit, Bland-Altman plots).

CONCLUSIONS

The CT and MR IMAT ratio measurements were highly correlated, indicating both modalities represent tissue quantification similarly.Level of Evidence: 2Technical Efficacy: 1.

The Effect of Abdominal Anatomy on the Measurement of Bone Mineral Density With Dual-Energy X-Ray Absorptiometry

OBJECTIVE

This study aimed to assess the effects of abdominal fat content and anatomical changes on the measurement of bone mineral density using dual-energy X-ray absorptiometry (DXA).

MATERIALS AND METHODS

The bone mineral density measurements were performed with quantitative computed tomography for patients who underwent DXA and abdominal CT on the same day. The effects of abdominal fat content and anatomic changes on the results of DXA were assessed.

RESULTS

Of the 43 patients, 88.3% were women, 11.7% were men, and the mean age was 55.6 years (range, 32-72). There was a significant relationship between the error in the measurement of T-scores with DXA and osteophytic new bone formation (P = 0.011). There were significant relationships between the error in detecting osteoporosis with DXA and osteophytic new bone formation, facet joint degeneration, and aortic calcification (P < 0.05).

CONCLUSIONS

Abdominal fat content does not significantly affect T-scores. However, DXA can give false-negative results in detecting osteoporosis, especially in patients with osteophyte new bone formation, facet joint degeneration, and aortic calcifications, all conditions primarily in elderly patients. In these cases, it is more appropriate to use quantitative computed tomography instead of DXA.

Bioelectrical impedance analysis versus quantitative computer tomography and anthropometry for the assessment of body composition parameters in China

Obesity, especially abdominal obesity, is correlated to increased risk of cardiovascular morbidity and mortality. It is urgent to search a simply method to predict visceral fat area (VFA). Herein, we evaluated the correlation of waist circumference (WC) measured by anthropometry and bioelectrical impedance analysis (BIA), and VFA estimated by BIA or measured by quantitative computed tomography (QCT) in China. The mean body mass index (BMI) was 25.09 ± 3.31 kg/m² and the mean age was 49.16 ± 9.19 years in 2754 subjects. VFA-BIA were significantly smaller than VFA-QCT in both BMI and age subgroups between male and female (p < 0.001). High correlation was observed for WC between BIA and manually (r = 0.874 for all, r = 0.865 for male and r = 0.806 for female) and for VFA between BIA and QCT (r = 0.512 for all). The intraclass correlation coefficient (ICC) showed the perfect agreement between BIA and manually to measure WC (ICC = 0.832 for all, 0.845 for male and 0.697 for female) and implied a good reliability for VFA between BIA and QCT with women among subgroups (ICC = 0.623 for all, ICC = 0.634 for age < 50 years and ICC = 0.432 for BMI > 24 kg/m²), whereas the good reliability was lost in men (ICC = 0.174). The kappa analysis showed a moderate consistency for VFA measured by BIA and QCT (Kappa = 0.522 with age < 50 years, 0.565 with age ≥ 50 years in male; Kappa = 0.472 with age < 50 years, 0.486 with age ≥ 50 years in female). In addition, BIA to estimate VFA (r = 0.758 in male, r = 0.727 in female, P < 0.001) has a stronger correlation with VFA measured by QCT than BMI and WC according to gender categories. Furthermore, ROC analysis showed the cut-off point of VFA measured by BIA for predicting visceral obesity was: 101.90 cm², 119.96 cm² and 118.83 cm² and the Youden’s index was 0.577, 0.577 and 0.651, respectively and the Kappa value was 0.532, 0.536 and 0.611 in unadjusted model, model 1 and model 2. In conclusion, being non-invasive and free of radiation, BIA can be used as a safe and convenient tool to estimate VFA in female; especially for monitoring the VFA of the same person, the BIA has superiority to a certain extent. However, the consistency is not most ideal between BIA and QCT. When using BIA to assess whether a person is visceral obesity, we must take into consideration age, BMI and WC. Therefore, we established a regression formula to reflect VFA-QCT by VFA-BIA, age, BMI, and WC. In addition, a more accurate formula is needed to match the CT data in China.

Impact of visceral adipose tissue on compliance of adjuvant chemotherapy and relapse-free survival after gastrectomy for gastric cancer: A propensity score matching analysis

BACKGROUND & AIMS

It has been reported that skeletal muscle mass loss during adjuvant chemotherapy and preoperative reduced skeletal muscle mass are associated with discontinuation of adjuvant chemotherapy. However, the relationship between visceral fat mass and compliance has not yet been investigated. In this study, we clarified the impact of low preoperative visceral fat mass on compliance and relapse-free survival (RFS) in gastric cancer patients.

METHODS

This was a retrospective cohort study of consecutive patients with gastric cancer who underwent radical gastrectomy for pathological stages II and III, and who received postoperative S-1 adjuvant chemotherapy between April 2008 and April 2017. Treatment failure was defined as discontinuation of adjuvant chemotherapy within 1 year. Visceral fat mass was measured preoperatively at the umbilical level on computed tomography, which was divided by height (m²⁾ to obtain the visceral adipose tissue index (VAI). Patients with a VAI below the median cut-off value were categorized as low-VAI, while those above the cut-off value were classified as high-VAI. We compared the treatment failure rate and RFS in the low-VAI and high-VAI groups after adjusting for group differences with propensity score matching. In addition, risk factors related to treatment failure and poor prognostic factors for RFS were analyzed in multivariate analyses that included all cases.

RESULTS

Among all 263 patients, treatment failure and recurrence were observed in 44 patients (16.7%) and 90 patients (34.2%), respectively. The median follow-up period was 52 months. After propensity matching, there were 101 patients in both low -and high-VAI groups. Treatment failure rate was higher (P = 0.037) and RFS was worse (P = 0.025) in the low-VAI group. In multivariate analyses, low-VAI was an independent risk factor associated with treatment failure (odds ratio (OR): 2.360, 95% CI: 1.120-5.000, P = 0.025), and was a poor prognostic factor for RFS (hazards ratio (HR):1.652, 95% CI: 1.057-2.582, P = 0.028).

CONCLUSIONS

Preoperative low visceral fat mass was an independent risk factor for poor compliance with adjuvant chemotherapy and a poor prognostic factor for RFS after radical gastrectomy in gastric cancer patients. Preoperative evaluation using body composition may be useful for post-treatment and prognosis prediction.

Excessive accumulation of visceral fat is associated with lower urinary symptoms including overactive bladder in female patients

Objective

To assess the relationship between visceral fat accumulation and lower urinary tract symptoms in female patients.

Methods

In this single‐center study, we enrolled all women who underwent screening abdominal computed tomography 3 months before the study, irrespective of whether they experienced lower urinary tract symptoms. The Overactive Bladder Symptom Score was used to assess subjective symptoms. Uroflowmetry and ultrasound assessment of post‐void residual urine were carried out to assess objective signs. We analyzed the relationship between lower urinary tract symptoms and various body fat accumulation parameters, including visceral fat area, visceral fat volume and total abdominal fat volume, assessed using computed tomography scans.

Results

A total of 182 patients were divided into the overactive bladder (n = 71, 39.0%) and the non‐overactive bladder (n = 111, 61.0%) groups. The visceral fat area, visceral fat volume and visceral fat volume/total abdominal fat volume values were all significantly higher in the overactive bladder group than in the non‐overactive bladder group (P < 0.001). Of these parameters, the visceral fat volume/total abdominal fat volume ratio showed the strongest correlation with the total Overactive Bladder Symptom Score (r = 0.394, P < 0.001). The maximum urine flow rate correlated negatively with the visceral fat volume/total abdominal fat volume value (visceral fat volume/total abdominal fat volume r = –0.289, P < 0.001). Subsequent multivariate analysis showed that a high visceral fat volume/total abdominal fat volume value, age and metabolic syndrome‐related diseases were independent risk factors for the presence of overactive bladder.

Conclusions

Excessive accumulation of visceral fat is independently associated with overactive bladder in females.

Exercise training-induced visceral fat loss in obese women: The role of training intensity and modality

Visceral fat loss in response to four-cycle ergometer training regimens with explicit differences in exercise intensity and modality was compared. Fifty-nine obese young women (body fat percentage ≥ 30%) were randomized to a 12-week intervention consisting of either all-out sprint interval training (SIT_all-out , n = 11); supramaximal SIT (SIT₁₂₀ , 120% V ˙ O_2peak , n = 12); high-intensity interval training (HIIT₉₀ , 90% V ˙ O_2peak , n = 12), moderate-intensity continuous training (MICT, 60% V ˙ O_2peak , n = 11), or no training (CON, n = 13). The total work done per training session in SIT₁₂₀ , HIIT₉₀ , and MICT was confined to 200 kJ, while it was deliberately lower in SIT_all-out . The abdominal visceral fat area (AVFA) was measured through computed tomography scans. The whole-body and regional fat mass were assessed through dual-energy X-ray absorptiometry. Pre-, post-, and 3-hour post-exercise serum growth hormone (GH), and epinephrine (EPI) were measured during selected training sessions. Following the intervention, similar reductions in whole-body and regional fat mass were found in all intervention groups, while the reductions in AVFA resulting from SIT_all-out , SIT₁₂₀ , and HIIT₉₀ (>15 cm² ) were greater in comparison with MICT (<3.5 cm² , P < .05). The AVFA reductions among the SITs and HIIT groups were similar, and it was concomitant with the similar exercise-induced releases of serum GH and EPI. CON variables were unchanged. These findings suggest that visceral fat loss induced by interval training at or above 90% V ˙ O_2peak appeared unresponsive to the change in training intensity. Nonetheless, SIT_all-out is still the most time-efficient strategy among the four exercise-training regimes for controlling visceral obesity.

Fat-modified computed tomography severity index (CTSI) is a better predictor of severity and outcome in patients with acute pancreatitis compared with modified CTSI

BACKGROUND

The amount of intra-abdominal fat on CT correlates positively with the severity of acute pancreatitis (AP). The objective of the study was to evaluate a fat-modified CT severity index (FMCTSI) and compare its performance with MCTSI.

MATERIALS AND METHODS

For this retrospective study, 99 patients with AP who underwent contrast-enhanced CT between 3 and 7 days after pain onset were divided into a training cohort (n = 75) and a validation cohort (n = 24). MCTSI was calculated. The total adipose tissue (TAT), visceral adipose tissue (VAT), and total to visceral fat ratio (TVFR) were computed using semi-automatic software. These parameters were given a score of 1-3. FMCTSI was calculated by adding the fat score to MCTSI. Concordance for diagnosing the severity of AP was assessed. Areas under receiver operating characteristic curves (AUC) for predicting clinical outcomes were compared between FMCTSI and MCTSI. The diagnostic performance of the FMCTSI in the validation cohort was also evaluated.

RESULTS

In the training cohort, our proposed FMCTSI performed better than MCTSI for all the outcome parameters. The highest concordance for the severity of AP was achieved for VAT-MCTSI. For all outcome parameters, the highest AUC was seen for TVFR-MCTSI. In the validation cohort, the FMCTSI achieved diagnostic performance similar to the training cohort with the highest AUC for TVFR-MCTSI.

CONCLUSION

FMCTSI is a better CT index than MCTSI for predicting the severity and clinical outcomes of AP. Among the various FMCTSI parameters, TVFR-MCTSI is the best performer.

The Prognostic Value of Body Fat Components in Metastasis Renal Cell Carcinoma Patients Treated with TKIs

Purpose

To assess the association between body fat components and survival status and tumor response for metastatic renal cell carcinoma (mRCC) patients treated with tyrosine kinase inhibitors (TKIs).

Patients and Methods

Patients with pathologically diagnosed and radiologically indicated mRCC were enrolled into the retrospective study. Three body fat components: total fat accumulation (TFA), visceral fat accumulation (VFA) and subcutaneous fat accumulation (SFA) were measured using standard CT scans. The clinical outcomes included progression-free survival (PFS), overall survival (OS), and tumor response rates. Univariate analysis and multivariate Cox proportion hazard regression models were used to find associated parameters and to calculate the adjusted hazard ratio (HR).

Results

A total of 146 patients were enrolled and the average age of patients was 56.5 years old. According to the univariate analysis, patients with an increased SFA and TFA had a longer PFS and OS. A similar phenomenon was observed among patients with ≥2 increasing body fat components about PFS and OS. As for multivariate analysis, SFA change (p=0.014) or the number of increasing body fat components (p=0.040) were independent indicators to predict PFS. In addition, SFA change (p=0.022) or the number of increasing body fat components (p=0.008) could independently predict OS. Moreover, a better disease control rate (p=0.028) was founded in patients with ≥2 increasing components. In the subgroup of patients with ≥2 metastasis sites, improved OS (p=0.017) and PFS (p=0.027) were found compared to those with <2 increasing components. Further multivariate analysis identified the number of increasing body fat components was an independent factor in predicting PFS (p=0.018) and OS (p=0.029).

Conclusion

Body fat accumulation, such as high SFA or TFA at progression, could improve the survival of patients with mRCC treated with TKIs, especially patients with higher tumor burden. It should be considered as an important parameter to predict the survival status of patients with mRCC.

Body Fat Area as a Predictive Marker of New-Onset Diabetes Mellitus After Kidney Transplantation

BACKGROUND

New-onset diabetes after kidney transplantation (NODAT) adversely affects patient survival. Excessive fat accumulation is generally considered a risk factor of NODAT. Body mass index (BMI) and abdominal circumference (AC) are frequently used to assess fat accumulation but cannot directly measure it. This study measured body fat area (BFA) via computed tomography and aimed to clarify whether preoperative BFA can predict the development of NODAT more accurately than BMI and AC.

METHODS

This retrospective study included 62 patients without diabetes mellitus who received living-donor kidney transplantation at our institute between July 2005 and April 2016. We investigated the association between preoperative BMI, AC, and BFA and the development of NODAT.

RESULTS

Eight patients (12.9%) developed NODAT during a mean follow-up period of 78.1 months. The preoperative BMI, AC, and BFA were markedly higher in NODAT patients than in patients without NODAT (P = .05, P = .02, P < .01, respectively). Correlation analyses revealed that BFA had a strong relationship with BMI (r = 0.68, P < .01) and AC (r = 0.77, P < .01). Receiver operating characteristic curve analyses demonstrated that BFA, compared to BMI and AC, had considerable predictive accuracy for the development of NODAT, with an area under the curve of 0.803 (sensitivity 75%, specificity 87%).

CONCLUSIONS

Preoperative BFA could be a predictive marker of NODAT in renal graft recipients. Our findings underline the importance of routine preoperative BFA measurements in clinical practice.

Arachidonic acid exacerbates diet-induced obesity and reduces bone mineral content without impacting bone strength in growing male rats

Long-chain polyunsaturated fatty acids modulate bone mass and adipocyte metabolism. Arachidonic acid (AA, C20:4 n-6) is elevated in obesity and postulated to stimulate bone resorption. This study aimed to determine the effect of AA on bone mass, quality, and adiposity in diet-induced obesity during growth. Male Sprague-Dawley rats (n=42, 4-week) were randomized into groups fed a control diet (CTRL, AIN-93G), high-fat diet (HFD, 35% kcal fat) or HFD + AA (1% w/w diet) for 6 weeks. Body composition, bone mineral density and microarchitecture were measured using dual-energy X-ray absorptiometry and micro-computed tomography. Red blood cell fatty acid profile was measured with gas chromatography. Group differences were evaluated using repeated measures two-way analysis of variance with Tukey-Kramer post hoc testing. Total energy intake did not differ among diet groups. At week 6, HFD + AA had significantly greater body fat % (12%), body weight (6%) and serum leptin concentrations (125%) than CTRL, whereas visceral fat (mass and %, assessed with micro-computed tomography) was increased in both HFD and HFD + AA groups. HFD + AA showed reduced whole body bone mineral content and femur mid-diaphyseal cortical bone cross-sectional area than HFD and CTRL, without impairment in bone strength. Contrarily, HFD + AA had greater femur metaphyseal trabecular vBMD (35%) and bone volume fraction (5%) compared to controls. Inclusion of AA elevated leptin concentrations in male rats. The early manifestations of diet-induced obesity on bone mass were accelerated with AA. Studies of longer duration are needed to clarify the effect of AA on peak bone mass following growth cessation.

Relationships between computed tomography-assessed density, abdominal fat volume, and glucose metabolism after sleeve gastrectomy in Japanese patients with obesity

In this study, we investigated the relationships between body weight (BW), computed tomography (CT)-assessed abdominal adipose tissue, and the glycemic metabolic profile in obese Japanese patients following laparoscopic sleeve gastrectomy (LSG). This study analyzed adipose tissue compartments using CT methods before and 1 year after LSG. Thirty obese patients were studied, and variables measured included visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), density of VAT (VAT-D), and density of SAT (SAT-D). We also examined the parameters in patients according to whether they had type-2 diabetes (T2DM). LSG induced significant losses in BW, SAT, and VAT after LSG. Additionally, SAT-D and VAT-D both increased and fasting plasma glucose (FPG) and HbA1c, but not C-peptide, decreased after surgery. ΔSAT and ΔVAT were positively related, and ΔSAT-D and ΔVAT-D were negatively related to ΔBW and/or FPG. Furthermore, a multivariate regression model showed that total BW loss (TBWL) was closely related to ΔSAT (β = 0.84; p < 0.001) and ΔVAT-D (β = -0.45; p < 0.05) and improvement of FPG was related to ΔVAT (β = 0.61; p < 0.05) after LSG. Finally, ΔFPG was correlated with ΔVAT in 16 T2DM patients (r = 0.58; p < 0.05) but not in non-T2DM patients. TBWL was related to ΔSAT and ΔVAT-D, and improvement of FPG was related to ΔVAT in obese Japanese patients after LSG.

Effect of Sodium Glucose Co-Transporter 2 Inhibitors on Liver Fat Mass and Body Composition in Patients with Nonalcoholic Fatty Liver Disease and Type 2 Diabetes Mellitus

BACKGROUND AND OBJECTIVE

Sodium glucose co-transporter 2 inhibitors increase urinary glucose excretion and reduce visceral adiposity and body weight, but their efficacy on patients with nonalcoholic fatty liver disease has not been sufficiently investigated. The aim of this study was to assess the effect of sodium glucose co-transporter 2 inhibitors on liver fat mass and body composition in patients with nonalcoholic fatty liver disease and type 2 diabetes mellitus.

METHODS

We retrospectively analyzed 17 patients with nonalcoholic fatty liver disease and type 2 diabetes who received sodium glucose co-transporter 2 inhibitors between November 2016 and July 2017. Changes in liver fat, subcutaneous and visceral fat, body composition, and liver function-related parameters were assessed after 24 weeks of sodium glucose co-transporter 2 inhibitor treatment and compared to baseline values.

RESULTS

Ten patients received dapagliflozin at 5 mg/day and seven patients received canagliflozin at 100 mg/day for 24 weeks. All patients completed the study without any serious adverse effects and achieved body weight loss and improved glycated hemoglobin levels. Liver fat mass evaluated by proton magnetic resonance spectroscopy was significantly reduced (19.1% vs. 9.2%, p < 0.01), and so were both subcutaneous and visceral fat mass. The body fat/body weight ratio decreased, whereas the skeletal muscle mass/body weight ratio increased. Liver function (aspartate aminotransferase, alanine aminotransferase, and γ-glutamyl transpeptidase) improved significantly.

CONCLUSIONS

Sodium glucose co-transporter 2 inhibitor treatment not only improved glycemic control but also reduced liver fat mass in patients with nonalcoholic fatty liver disease and type 2 diabetes. Body weight loss was primarily attributable to a reduction in fat mass, especially visceral fat. Thus, sodium glucose co-transporter 2 inhibitors could potentially serve as a therapeutic agent for patients with nonalcoholic fatty liver disease and type 2 diabetes.

Anthropometric Obesity Indices were Stronger than CT-Based Indices in Associations with Carotid Intima-Media Thickness in Japanese Men

AIM

Computed tomography (CT) can directly provide information on body compositions and distributions, compared to anthropometric indices. It has been shown that various obesity indices are associated with carotid intima-media thickness (IMT). However, whether CT-based obesity indices are stronger than anthropometric indices in association with atherosclerosis remains to be determined in a general population.

METHODS

We cross-sectionally assessed carotid IMT using ultrasound in 944 community-dwelling Japanese men free of stroke and myocardial infarction. CT image at the L4-L5 level was obtained to compute areas of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT). Anthropometric measures assessed included body mass index (BMI), waist circumference, and waist-to-hip ratio. Using multivariable linear regression, slopes of IMT per 20^th to 80^th percentile of each index were compared. We also compared the slope of index with simultaneous adjustment for BMI in the same model.

RESULTS

Areas of VAT and SAT were positively associated with IMT, but not stronger than those of anthropometric indices in point estimates. Among all obesity indices, BMI was strongest in association with IMT after adjusting for age and lifestyle factors or further adjusting for metabolic factors. In simultaneous adjustment models, BMI, but not CT-based indices, remained significant and showed the strongest association.

CONCLUSIONS

In community-dwelling Japanese men, anthropometric obesity indices, BMI in particular, were more strongly associated with carotid atherosclerosis than CT-based obesity indices. The association of general obesity with carotid atherosclerosis was strong and adding CT-based obesity measure did not considerably influence in the association.

Visceral obesity and short-term outcomes after laparoscopic rectal cancer resection

BACKGROUND

Complications after rectal resection are frequent. Recently, methods to assess visceral obesity (VO) have become available as an alternative to measurement of body mass index (BMI). The aim of this study was to examine the association between visceral fat volume (VFV) and the short-term outcomes after laparoscopic low anterior resection (LLAR) in patients with rectal cancer.

METHODS

We studied a consecutive series of patients undergoing LLAR at Bispebjerg University Hospital from 01.01.2013 to 01.01.2016. Preoperative VFV was calculated from abdominal CT scans using an automatic segmentation tool. The primary outcome was anastomotic leakage (AL). Secondary outcomes included conversion to open surgery, number of lymph nodes harvested, the rates of 30-day complications as well as reoperations, and 1-year survival.

RESULTS

A total of 102 patients were included. VO was defined as a VFV above the 75 percentile. Thirteen (12.7%) patients developed AL, four (15.4%) of whom were in the VO group (p = 0.900). At least one postoperative complication developed in 38 (37.3%) patients, with no significant difference between the VO and non-VO patients after univariable analysis (42.3% vs. 35.4%, p = 0.702) or multivariable adjustment (OR 1.01, 95% CI 0.38-2.65, p = 0.984). VO was significantly associated with an increased incidence of conversion to open surgery (OR 4.30, 95% CI 1.29-14.86, p = 0.018). There was a significant difference in the number of harvested lymph nodes between the two groups (mean 23.5 vs. 29.1, p = 0.045).

CONCLUSIONS

In this study on patients undergoing laparoscopic rectal resection, VO was not associated with development of AL or other complications. However, we found that visceral obesity was associated with an increased risk of conversion to open surgery.

The Significance of the Effect of Visceral Adiposity on Left Ventricular Diastolic Function in the General Population

We evaluated the association between visceral adiposity and left ventricular (LV) diastolic function in association with plasma adiponectin levels in 213 subjects without overt cardiac diseases. Abdominal visceral fat area was quantified by computed tomography. Excessive visceral fat was significantly associated with impaired diastolic parameters including E/A, E′ and E/E′. Although serum adiponectin levels decreased with increased visceral adiposity, there was no independent association between serum adiponectin levels and diastolic parameters, which suggest that the role of adiponectin in this association might be indirect.

Visceral obesity in Asian living kidney donors significantly impacts early renal function after donor nephrectomy

INTRODUCTION

Obesity may be a risk factor for kidney donors to develop reduced renal function. The Framingham heart study suggested that visceral adipose tissue (VAT) confers a more adverse metabolic profile compared with subcutaneous adipose tissue (SAT). Asians tend to have a higher VAT composition and it is unclear if their kidney function is affected differently. We hypothesized that Asian living kidney donors who have visceral obesity are at a higher risk of renal function deterioration 1 year after donation.

METHODS

Between 2011 and 2014, we retrospectively evaluated data from 73 consecutive patients (52% male; mean age 44.9 ± 11.7 years) before they underwent donor nephrectomy and at their 1 year routine follow-up. VAT and SAT were measured at the level of the umbilicus on pre-operative computerized tomography (CT). Visceral obesity (VO) was defined as a VAT > 100 cm [2] and patients were then further divided and compared in two subgroups: VAT > 100 and < 100 cm [2]. Estimated glomerular filtration rate (eGFR, mL/min per 1.73 m [2]) was calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation pre-operatively and 1 year post-operatively.

RESULTS

Both subgroups had similar baseline kidney function (P = NS) pre-operatively. At the 1 year follow-up, patients with VO experienced a more significant decline of renal function (109 ± 9 to 89 ± 8 mL/min per 1.73 m²), compared to those without VO (111 ± 12 to 96 ± 11 mL/min per 1.73 m², P = 0.013). VO was associated with a body mass index (BMI) > 25 kg/m² (P < 0.001), male gender (P < 0.001) and older age at the time of donor nephrectomy (48.0 vs 39.5 years, P = 0.01). The presence of hypertension or hyperlipidaemia pre-operatively, choice of surgical approach, and post-operative complication rates, did not differ significantly between the subgroups.

CONCLUSIONS

Visceral obesity as defined by VAT > 100 cm² at the level of the umbilicus on cross-sectional imaging, may have a significant impact on early renal function after donor nephrectomy. Adiposity markers, as measured by cross-sectional CT imaging, may be incorporated into routine pre-operative kidney donor workup.

Relationship Between Visceral Obesity and Postoperative Inflammatory Response Following Minimally Invasive Esophagectomy

BACKGROUND

Esophagectomy for esophageal cancer is one of the most invasive surgeries. However, the factors influencing postoperative systemic inflammatory response following esophagectomy have not been elucidated. Recently, visceral fat has been shown to play an important role in both chronic and acute inflammation. In this study, we assessed the relationship between visceral obesity and postoperative inflammatory response following minimally invasive esophagectomy (MIE).

METHODS

Visceral fat area (VFA) was measured using computed tomography in 152 patients undergoing MIE for esophageal cancer. We assessed perioperative serum C-reactive protein (CRP) levels preoperatively and on postoperative days (PODs) 1-5 and analyzed the relationship between VFA and perioperative serum CRP levels.

RESULTS

VFA was positively associated with preoperative serum CRP level (P < 0.001). Univariate analysis revealed that VFA was significantly associated with increased serum CRP levels on PODs 1-5 (P < 0.001 for each day), whereas multivariate analysis revealed that it was independently associated with increased serum CRP levels on PODs 1-4 (P = 0.033, 0.035, 0.001, and 0.006, respectively). Similar results were observed in patients who did not have postoperative infectious complications, such as pneumonia, anastomotic leak, and surgical site infection. VFA was not an independent risk factor for the occurrence of these postoperative infectious complications.

CONCLUSIONS

Visceral obesity might be associated with chronic inflammation in patients with esophageal cancer and promote postoperative inflammatory response following MIE.

Correlation between DXA and laboratory parameters in normal weight, overweight, and obese patients

OBJECTIVE

The aim of this study was to review the existence and types of correlations between body composition densitometric parameters and laboratory values associated to cardiometabolic risk.

METHODS

We retrospectively analyzed data from 316 individuals in the weight range from normality to super-obesity, submitted to total body dual-energy x-ray absorptiometry (DXA) scans and routine biochemistry at S.Orsola-Malpighi Hospital from June 2010 to March 2014. The study included 182 women, 45.8 ± 13.4 y of age, with a body mass index (BMI) of 31.5 (± 11) kg/m² (group F) and 134 men, 45.4 ± 13.6 y of age, with a BMI of 27.6 (± 7.8) kg/m² (group M). All patients underwent whole-body scan (Lunar iDXA, GE Healthcare, Madison, WI, USA) and laboratory analysis (blood fasting glucose, total cholesterol, high-density lipoprotein cholesterol, tricylglycerides [TGs], aspartate aminotransferase, and alanine aminotransferase). Correlation between laboratory values and total body and regional fat mass (including visceral adipose tissue [VAT] and subcutaneous adipose tissue in the android region), and lean mass parameters were analyzed with linear and stepwise regressions analysis (significance limit, P < 0.05). Receiver operating characteristic curves were performed to assess the accuracy of the best-fit DXA parameter (VAT) to identify at least one laboratory risk factor.

RESULTS

In both groups, BMI and densitometric parameters showed a linear correlation with fasting blood glucose and TG levels and an inverse correlation with high-density lipoprotein cholesterol (P < 0.05), whereas no correlation was observed with total cholesterol levels. The only densitometric parameter retained in the final model of stepwise multiple regression was VAT for fasting blood glucose (group F: β = 0.4627, P < 0.0001; group M: β = 0.6221, P < 0.0001) and TG levels (group F: β = 0.4931, P < 0.0001; group M: β = 0.1990, P < 0.0261) independently of BMI. The optimal cutoff points of VAT to identify the presence of at least one laboratory risk factor were >1395 g and >1479 cm³ for men and >1281 g and >1357 cm³ for women.

CONCLUSIONS

DXA analysis of VAT is associated with selected laboratory parameters used for the evaluation of cardiometabolic risk and could be per se a helpful parameter in the assessment of clinical risk.

Hepatic steatosis is highly prevalent across the paediatric age spectrum, including in pre-school age children

BACKGROUND

The prevalence of non-alcoholic fatty liver disease (NAFLD) in children is 8% in the general population, and 34% in the context of obesity. There is a paucity of data on the prevalence of hepatic steatosis in healthy children in Ontario.

AIMS

To determine the prevalence of hepatic steatosis using abdominal computed tomography (CT) scans in a cohort of previously healthy children across the paediatric age spectrum in Ontario, Canada, and to determine any association between measures of abdominal adiposity and hepatic steatosis.

METHODS

Retrospective review of the SickKids Trauma Database from 2004-2015. Previously healthy children ages 1-17 years having undergone an abdominal CT scan as a part of routine trauma assessment were included, and those with an intra-abdominal injury excluded. Steatosis was defined as a difference between liver and spleen attenuation ≤-25HU. The percentage of the total area occupied by abdominal subcutaneous adipose and visceral adipose tissue was measured. Anthropometrics and baseline demographics were collected.

RESULTS

A total of 503 (51% male) children with mean (±SD) age 9.5 ± 4.5 years and weight z-score of 0.37 ± 1.05 were studied. Seventy-seven (15%, 95% CI [12%-18%]) had hepatic steatosis; no differences found between sexes or across age quartiles. The abdominal subcutaneous adipose tissue area was greater in those with hepatic steatosis compared to those without (32% [22-42] vs 24% [17-36], P = 0.003). The visceral adipose tissue area was significantly greater in older children ≥9.8 years with hepatic steatosis (7.7% [5.1-10] vs 6.6% (4.9-8.5), P = 0.04).

CONCLUSION

Hepatic steatosis was highly prevalent in previously healthy children in Ontario, including children of pre-school age. We found an association between hepatic steatosis and abdominal subcutaneous adipose tissue, and in older children with visceral adipose tissue.

Correlation between Non-Alcoholic Fatty Liver Disease and Visceral Adipose Tissue in Non-Obese Chinese Adults: A CT Evaluation

Objective

To investigate the correlation between non-alcoholic fatty liver disease and visceral adipose tissue in non-obese Chinese adults using computed tomography (CT).

Materials and Methods

The study included 454 subjects undergoing abdominal CT scan. Degree of CT attenuation in liver and spleen, and the degree of fat infiltration in liver were evaluated according to three indices: the attenuation value of liver parenchyma (CT_LP), the attenuation ratio of liver and spleen (LS_ratio) and the attenuation difference between liver and spleen (LS_dif). Visceral fat area (VFA) and total fat area (TFA) at L2/3 and L4/5 levels were measured, and the abdominal subcutaneous fat area (SFA) was calculated. Bivariate correlation analysis was carried out to determine the correlation among these factors.

Results

In men, VFA, SFA and TFA at L2/3 and L4/5 levels showed significant differences in terms of the three indices to distinguish fatty liver from non-fatty liver (all, p < 0.001). In men, all the three indices showed negative correlation with TFA, SFA and VFA (all, p < 0.001). The negative correlation between the three indices and VFA at the L2/3 level was higher than at L4/5 level (r = −0.476 vs. r = −0.340 for CT_LP, r = −0.502 vs. r = −0.413 for LS_ratio, r = −0.543 vs. r = −0.422 for LS_dif, p < 0.001, respectively). The negative correlation between LS_ratio, LS_dif and VFA at L2/3 and L4/5 levels was higher than SFA at the corresponding level. In women, all the three indices showed negative correlation with VFA and TFA at L2/3 and L4/5 levels, and the negative correlation between CT_LP and VFA was higher at L2/3 level than at L4/5 level (r = −0.294 vs. r = −0.254, p < 0.001).

Conclusion

In non-obese Chinese adults, the degree of hepatic fatty infiltration showed a strong correlation with abdominal fat on CT. VFA at L2/3 level was more closely related to fatty liver compared with VFA at L4/5 level.

Abdominal fat distribution in diffuse idiopathic skeletal hyperostosis and ankylosing spondylitis patients compared to controls

AIM

To evaluate abdominal fat distribution (subcutaneous adipose tissue [SAT] and visceral adipose tissue [VAT]) in two enthesopathy-related diseases with known correlation to metabolic syndrome (MS): diffuse idiopathic skeletal hyperostosis (DISH) and ankylosing spondylitis (AS) compared with controls.

MATERIALS AND METHODS

Abdominal computed tomography (CT) examinations of 43 DISH (Resnick radiographic criteria) patients, 31 AS (Modified New York Criteria) patients and 42 age- and gender-matched (to DISH) controls (males: 29; 29; 27 and mean age: 71.7±7; 56.1±16; 72.7±8 years, respectively) were evaluated and compared for VAT and SAT surface areas on mid L3, L4, L5 levels.

RESULTS

AS patients were significantly younger compared to DISH patients and controls. No significant differences were observed between VAT and SAT of DISH and AS patients or between SAT values in all groups even after correction for age. VAT was higher in DISH and AS patients compared to controls on all three levels, but reached significance (p<0.05) only for DISH patients (L3: 24.34/23.6/18.43; L4: 23.85/22.21/18.05; L5: 19.09/18.94/14.24 mm², respectively). This did not change after correction for age. The VAT/SAT ratio was significantly larger in DISH and AS patients on all levels compared to controls.

CONCLUSION

The higher VAT surface area, a known marker for MS, which by itself is associated with bone proliferation, in DISH and AS patients compared to controls substantiates its role as a potential surrogate marker for MS as well as suggests a potential shared pathogenic pathway for enthesopathic excessive bone production in DISH and AS.

Obesity does not affect peri- and postoperative outcomes of transabdominal laparoscopic adrenalectomy

Laparoscopic adrenalectomy is the gold standard procedure for most adrenal tumors. Obesity is considered as a risk factor for surgical complications. This study aimed to evaluate whether obesity affects peri- and postoperative outcomes of transabdominal laparoscopic adrenalectomy using body mass index (BMI). This retrospective study included 98 patients who underwent transabdominal laparoscopic adrenalectomy between January 2011 and December 2016. We divided the patients into 2 groups: non-obese group (BMI < 25 kg/m2) and obese group (BMI ≥ 25 kg/m2). We assessed perioperative outcomes and postoperative complications between the groups. A total of 98 patients were analyzed (70 without obesity and 28 with obesity). There were no significant differences between the non-obese and obese groups regarding operative time (111 vs 107 min; p = 0.795), blood loss (3.5 vs 3.5 ml; p = 0.740), rate of placement of additional trocars (14.3% vs 17.9%; p = 0.657), rate of open conversion (2.6% vs 3.6%; p = 0.853), and postoperative length of hospital stay (6 vs 5 days; p = 0.237). Furthermore, obesity was not a significant risk factor for postoperative complications (postoperative bleeding, wound infection, and pneumonia). There are no significant differences in peri- and postoperative outcomes of transabdominal laparoscopic adrenalectomy in patients with obesity compared with those without obesity. Transabdominal laparoscopic adrenalectomy is feasible and safe for patients with obesity.

Adipose tissue location and contribution to postinjury hypercoagulability

OBJECTIVES

Obesity is associated with a hypercoagulable state at baseline and following injury. The anatomic location of adipose deposition may influence the type of thrombotic event, with visceral adipose tissue (VAT) associated with arterial thrombosis and subcutaneous adipose tissue (SAT) predisposing to venous thrombosis. We sought to determine whether adipose tissue amount and location correlated with measures of coagulation.

METHODS

All adult Level I trauma activations at our institution between January 2013 and August 2014 who underwent admission abdominal computed tomography scan and had admission rotational thromboelastometry measurements were included. Patients were excluded for history of anticoagulant use and known coagulopathy/hypercoagulable state. Admission computed tomography was used to obtain cross-sectional VAT and SAT areas at the umbilicus utilizing a novel software system; VAT and SAT measurements were associated with markers of coagulation utilizing Spearman correlation and stepwise linear regression with significance set at p < 0.05.

RESULTS

Two hundred forty-two patients met inclusion and exclusion criteria. Sixty-nine percent of patients sustained blunt injury, 79% were male, mean age was 40 years, 25% were obese or morbidly obese, and mean Injury Severity Scale score was 17. Seventeen percent of patients had acute deep venous thrombosis or pulmonary embolism during hospitalization. Neither SAT nor VAT correlated with prothrombin time, international normalized ratio, or partial thromboplastin time. Subcutaneous adipose tissue correlated positively with platelet count. Visceral adipose tissue and SAT correlated negatively with clot formation time and positively with TEM fibrinogen, α angle, maximum clot firmness, and lysis at 30 minutes; stronger correlations and greater significance were seen between SAT and these measures except for lysis at 30 minutes. Stepwise linear regression confirmed significant relationships between SAT and clot formation time, AA, and maximum clot firmness; VAT showed a significant relationship with TEM fibrinogen.

CONCLUSIONS

Increased adipose tissue correlates with relative hypercoagulability following trauma. Subcutaneous adipose tissue shows a stronger relationship with functional measures of coagulation, suggesting that SAT may be associated with hemorrhage resistance and hypercoagulability after injury.

LEVEL OF EVIDENCE

Prognostic study, level IV.

Pancreas volume reduction and metabolic effects in Japanese patients with severe obesity following laparoscopic sleeve gastrectomy

This study aimed to assess the relationship between the metabolic effect after laparoscopic sleeve gastrectomy (LSG) in morbidly obese Japanese patients, with or without type 2 diabetes mellitus (T2DM), and improved pancreatic steatosis (PS). The study enrolled 27 morbidly obese Japanese patients who were undergoing LSG. Their clinical and metabolic effects were evaluated at baseline and six months after LSG. Pancreas volume (PV), pancreatic attenuation (PA), and splenic attenuation (SA) were measured using a 64-row computed tomography (CT). Changes in PV, PA-SA, and PA/SA were evaluated. The mean body-weight loss, body mass index loss, and percentage of excess weight loss (%EWL) were -34.4 kg (p < 0.001), -11.0 kg/m² (p < 0.001), and 43.7%, respectively. The mean PV was 96.7 mL at baseline, and it decreased six months after LSG (-16.3mL, p < 0.001). The mean PA significantly increased six months after LSG (9.5 HU, p < 0.001). PA-SA (-23.2 HU vs. -13.3 HU, p = 0.003), and PA/SA (0.54 vs. 0.73, p < 0.001) also significantly increased six months after LSG. In T2DM patients, decreased PV correlated with decreased fasting blood sugar, decreased insulin, and reduced liver volume. In conclusion, PV significantly decreased after LSG in morbidly obese Japanese patients, and that decrease correlated with improvements in PS. In addition, PS plays an important role of development and progression of insulin resistance and T2DM.

Comparison of Visceral Fat Accumulation and Metabolome Markers among Cats of Varying BCS and Novel Classification of Feline Obesity and Metabolic Syndrome

As in humans, obesity and its associated diseases represent the most significant threat to the health of veterinary populations. Previous human studies have provided insights into the risk factors of obesity, complex pathogenesis of obesity-associated diseases, and their life-threatening consequences. In humans, the “metabolic syndrome” represents a cluster of metabolic risk factors associated with the development of cardiovascular disease. Risk factors for metabolic syndrome, such as diabetes, obesity, high blood pressure, and its complications increase health-care utilization and medical expenses. Early diagnosis and intervention through preemptive approach is in need, and the new International Diabetes Federation definition of MS serves as the universally accepted diagnostic tool that is accessible in clinical settings. In veterinary populations, especially in cats, similar pathophysiological path and disease progression to the development of MS, such as adipokine dysregulations, chronic inflammation, lipotoxicity, are expected. The aim of this manuscript is twofold. First of all, it presents our preliminary feline obesity study that serves as the basis for discussion of obesity and its metabolic impact on feline population. In this study, we observed the effects of weight gain on energy metabolism using metabolome markers, such as adiponectin (ADN) and proinflammatory cytokines, in correlation with other common biochemical parameters in 14 clinically healthy cats of varying weight status. Further, we evaluated the visceral fat accumulation in three subjects of varying Body Condition Scores via computed tomography imaging and laparoscopic examination, and assessed the adipocyte type and size histologically. Mutually antagonizing changes in ADN and visceral adipose tissue (VAT) reflected the pathophysiological derangements leading to MS earlier than the common biochemical predictors such as glucose, liver values, and lipid markers. Second, it proposes the novel diagnostic and classification method of feline obesity and MS, based on the established diagnostic criteria of human MS and the presented study results. The results supported our novel “classification of feline obesity” and “Feline MS diagnostic criteria,” suggesting the need to complement ADN measurement with VAT volume to better understand the pathogenesis of metabolic disturbances in the feline population.

Visceral adiposity and cancer survival: a review of imaging studies

Although obesity is a well-known risk factor for cancer, the association between obesity and cancer survival remains controversial. This is partially due to the inability of conventional obesity measures to directly assess adiposity or adipose tissue distribution. As a metabolic organ, visceral adipose tissue (VAT) secrets a variety of cytokines and cytokine-like factors, potentially affecting cancer survival. The objective of this review was to investigate the influence of imaging-assessed VAT on cancer survival. A total of 22 studies assessing the impact of visceral adiposity on survival were included. Negative associations between VAT and survival were more frequently observed among patients with colorectal (four of six studies) and pancreatic (three of five studies) cancers, compared to higher VAT predicting longer survival in most studies of renal cell carcinoma patients (four of five studies). Methodological limitations, including unstandardised VAT measurement methods, lack of other body composition measurement (i.e. muscle mass), small sample size and heterogeneous cohort characteristics, may explain controversial findings related to the impact of VAT on cancer survival.

Utility of skinfold thickness measurement in non-ambulatory patients with Duchenne muscular dystrophy

Nutritional disorders in Duchenne muscular dystrophy (DMD) worsen the medical condition. In particular, obesity is a serious problem that increases the risk of cardiomyopathy and affects nursing care. However, it is often difficult to evaluate body fatness in the advanced stages of DMD. Skinfold thickness measurement is a classical method to evaluate body fatness and is easily performed, even for bed-bound patients at home. We aimed to investigate the utility of skinfold thickness measurement in non-ambulatory DMD patients. Twenty-two patients with non-ambulatory, steroid-naive DMD ranging in age of 12-47 years were evaluated by body mass index (BMI), blood tests, measurement of triceps skinfold thickness (TSF), and abdominal computed tomography (CT) measurement of the areas of both subcutaneous and visceral fat. TSF showed good correlation with BMI (r = 0.80; p < 0.001), serum triglycerides (r = 0.67; p < 0.01), area of subcutaneous fat (r = 0.85; p < 0.0001), and area of visceral fat (r = 0.76; p < 0.0001). These results indicate the skinfold thickness measurement may be applicable as a screening tool in clinical practice where CT and magnetic resonance imaging assessment is often difficult in patients with advanced DMD.

Visceral Obesity is Associated with Poor Prognosis in Pancreatic Adenocarcinoma

An association between obesity and unfavorable outcomes for various types of malignancy has been established. Nevertheless, the impact of visceral obesity (VO) on outcomes in pancreatic cancer is still unknown and controversial. The aim of this study was to uncover an association between VO and pancreatic cancer outcomes. We retrospectively reviewed 499 patients with pancreatic cancer who were diagnosed and treated in Severance Hospital from January 2006 to December 2011. Compared to the low-VO group (n = 260), the high-VO group (n = 239) was mostly male (68.2% vs. 31.8%, P < 0.001) and was more likely to have current smoking status (29.7% vs. 17.7%, P < 0.001), current alcohol intake status (52.3% vs. 26.4%, P < 0.001) and diabetes mellitus (54.4% vs. 31.9%, P = 0.028). The progression free survival (PFS) and overall survival (OS) were found to be significantly shorter by the Kaplan-Meier method in the high-VO group than in the low-VO group (PFS; P = 0.044, OS: P = 0.013). In addition, the higher percentage of visceral fat was correlated with more lymph node metastasis and shorter OS (P = 0.011 and P = 0.017, respectively). In patients with pancreatic cancer, VO at the time of diagnosis is associated with negative outcomes, such as shorter PFS and OS.

Feasibility of simultaneous 18F-FDG PET/MRI for the quantitative volumetric and metabolic measurements of abdominal fat tissues using fat segmentation

BACKGROUND

Quantification of volume and inflammatory activity in the fat tissue is important because these are closely related to type 2 diabetes mellitus and cardiovascular disease. Fluorine-18 fluorodeoxyglucose (F-FDG) PET/computed tomography (CT) has been utilized to measure the metabolic activity of fat tissue. In this study, we assessed the feasibility of simultaneous PET/magnetic resonance (MR) in metabolic and volumetric measurements of fat tissue and the potential advantage over PET/CT.

METHODS

Twenty-four healthy individuals were enrolled, who underwent simultaneous F-FDG PET/MRI. Twenty-five F-FDG PET/CT scans were selected. Isocontour volumes of interest (VOIs) were used to segment and separate visceral fat (VF) and abdominal subcutaneous fat (SF) in using the MR image (T1 DIXON VIBE sequence) of PET/MR and the CT image of PET/CT. Volume, mean standardized uptake value of VF, and SF VOIs were calculated.

RESULTS

Overlap between F-FDG PET and VF VOI was better in F-FDG PET/MR than PET/CT. The mean standardized uptake value of VF was associated with the degree of intestinal uptake on F-FDG PET/CT, but not on F-FDG PET/MR. Volumetric and metabolic measurements using F-FDG PET/MR showed an excellent reproducibility, with a high intraclass correlation coefficient between different observers (0.951-0.997). The measured metabolic activity was higher in VF than SF.

CONCLUSION

We established a method for the quantitative measurement of volume and metabolic status of abdominal VF and SF using simultaneous F-FDG PET/MR. F-FDG PET/MR has an advantage over F-FDG PET/CT in terms of being less confounded by intestinal uptake. This method could be used to assess the inflammatory activity of fat tissue, which is a major risk factor for type 2 diabetes mellitus and cardiovascular disease.

Fully automatic and nonparametric quantification of adipose tissue in fat-water separation MR imaging

Despite increasing demand and research efforts, currently there is no consensus on the protocol for automated and reliable quantification of adipose tissue (AT) and visceral adipose tissue (VAT) using MRI. The purpose of this study was to propose a novel computational method with enhanced objectiveness for the quantification of AT and VAT in fat-water separation MRI. 3T data from IDEAL were acquired for the fat-water separation. Fat tissues were separated from nonfat regions (background air, bone, water, and other nonfat tissues) using K-means clustering (K = 2). From the binary fat mask, arm regions were separated from body based on the relative size of connected component. AT was obtained from the binary body fat mask. With the initial contour as the outer boundary of body fat, the subcutaneous adipose tissue (SAT) and VAT were separated using deformable model driven by a specifically generated deformation field pointing to the inner boundary of SAT. The proposed method was tested on 16 patients with dyslipidemia and evaluated by comparing the correlation with semi-automatic segmentation results. Good robustness was also observed in the proposed method from the Bland-Altman plots. Compared to other established fat segmentation methods, the proposed method is highly objective for fat-water separation MRI with minimal variability induced by subjective parameter settings.

Visceral to total obesity ratio and severe hydronephrosis are independently associated with prolonged pneumoperitoneum operative time in patients undergoing laparoscopic radical nephroureterectomy for upper tract urothelial carcinoma

BACKGROUND

Our aim was to evaluate the effect of visceral obesity and impact of severe hydronephrosis on surgical complexity in patients undergoing laparoscopic radical nephroureterectomy (LRNU).

METHODS

From January 2000 to December 2013, 169 patients underwent radical nephroureterectomy at our institution. We retrospectively reviewed the medical records of 70 patients who underwent LRNU. We measured total fat area (TFA) and visceral fat area (VFA) at the level of the umbilicus using computed tomography. We defined accumulated visceral fat distribution as a VFA/TFA ratio ≥0.45. Ipsilateral hydronephrosis was graded from 0 to 4 by two uro-radiologists blinded to the clinical outcomes.

RESULTS

Among the 70 patients, VFA/TFA ratio was ≥0.45 in 40 patients (57.1%) and 28 (40.0%) had severe hydronephrosis (grade 3 or greater). Patients with a VFA/TFA ratio ≥0.45 had significantly longer pneumoperitoneum and total operation times compared to their counterparts (p = 0.047 and p = 0.002, respectively). Patients with severe hydronephrosis had significantly longer pneumoperitoneum and total operative times compared to their counterparts (p = 0.006 and p = 0.002, respectively). Multivariate logistic regression analysis showed that a high VFA/TFA and severe hydronephrosis were independent predictive factors for prolonged pneumoperitoneum (p = 0.048, HR = 2.90; p = 0.015, HR = 3.82, respectively) and total operative times (p < 0.001, HR = 18.7; p = 0.003, HR = 10.7; respectively). Other pre-clinical factors such as age, gender, BMI, clinical stage, tumor size, location, laterality, degree of perinephric stranding, and surgical procedure did not affect the operation times.

CONCLUSION

The present data indicated that the visceral type of adipose accumulation and presence of severe hydronephrosis could provide preoperative information on the degree of technical difficulty associated with LRNU.