Visceral Adipose Tissue Volume Research Articles

Long-Term Improvement in Cardiorespiratory Fitness Ameliorates Insulin Sensitivity beyond Changes in Visceral/Ectopic Fat among Men with Visceral Obesity.

The SYNERGIE study documented the effects on cardiometabolic risk (CMR) indices of a 1-year lifestyle intervention targeting physical activity (PA) and diet followed by a 2-year maintenance period in men with visceral obesity. Improvements in CMR markers and a decrease in low-attenuation muscle (LAM) area were observed after 1 year. Despite a rebound in visceral adipose tissue (VAT) during the maintenance period, insulin resistance (IR) improved. We tested the hypothesis that variations in cardiorespiratory fitness (CRF) and LAM could explain the long-term improvement in IR. A health (n = 88; mean age 49.0 ± 8.2 years) and fitness (n = 72) evaluation was performed at 0, 1, and 3 years. Participants were classified into two groups based on their CRF response over the maintenance period (worsening: CRF- vs. maintenance/improvement: CRF+). During the maintenance period, changes in the psoas and core LAM areas correlated with changes in IR (r = 0.27; p < 0.05 and r = 0.34; p < 0.005) and changes in CRF (r = -0.31; p < 0.01 and r = -0.30; p < 0.05). IR improved in the CRF+ group (p < 0.05) but remained stable in the CRF- group. Men in the CRF+ group regained half of the changes in VAT volume and LAM at the psoas and mid-thigh compared to the CRF- group (p < 0.05). These results support the importance of targeting VAT and CRF/PA for the long-term management of CMR in men with visceral obesity.

DETERMINANTS OF PHYSIOLOGICAL RESPONSE TO EXERTIONAL HEAT STRESS IN HUMANS

INTRODUCTION AND AIMS Previous field studies of exercise undertaken in hot conditions reported dissociation between heat-related symptoms and body core temperature (Tc) elevation. This prompted us to examine physiological mechanisms underpinning responses to exertional heat exposure in a controlled laboratory experiment. METHODS Thirty-eight apparently healthy participants had body composition (DEXA) and fitness (V̇O2peak) measured in a preliminary visit. Tc, heart rate (HR), exercise intensity (V̇O2) and echocardiographic measures of end-diastolic volume (EDV), stroke volume (SV) and cardiac output (Q̇) were measured at rest and at 30-minute intervals throughout a two-hour walk (5km/h and 2% gradient) in a climate-controlled chamber (40⸰C and 50% relative-humidity). RESULTS Twenty-seven participants completed the experiment (Completers; Com), 7 were stopped due to Tc exceeding 39⸰C (Hyperthermics; Hyp). Four participants did not complete the protocol due to adverse symptoms and were excluded from this analysis. Hyp had significantly greater Tc at 60-minutes (38.6±0.5⸰C vs. 38.0±0.3⸰C; P=&amp;lt;0.001) and 90-minutes (39.0±0.3⸰C vs. 38.3±0.3⸰C; P=&amp;lt;0.001) than Com. Baseline V̇O2peak (ml.kg-1.min-1) did not differ between Hyp and Com (P=0.248). Whilst body weight and lean body mass did not significantly differ between Hyp and Com, visceral adipose tissue (VAT) volume (463.2±194.3cm3 vs. 259.9±284.4cm3 P=0.014) and mass (437.0±183.1g vs. 245.2±268.2g P=0.013) were significantly greater in Hyp vs Com. In Hyp, HR change from baseline was greater at 60-minutes (Δ57±15bpm vs. Δ36±18bpm; P=0.01) and 90-minutes (Δ63±20bpm vs. Δ42±19bpm; P=0.017), whilst change in EDV (Δ-22.7±11.4ml vs. Δ-6.92±11.2ml; P=0.016) and SV (Δ-19.4±6.1ml vs. Δ-0.7±7.5ml; P=&amp;lt;0.001) were significantly reduced in Hyp compared to Com. CONCLUSION During walking in the heat, subjects who became hyperthermic had significantly higher baseline visceral fat mass and early signs of exaggerated haemodynamic burden during exertional heat exposure. This study has implications for the identification of appropriate variables for establishing safe work limits during heat exposure in military and work-related contexts.

Visceral adipose tissue reduction measured by deep neural network architecture improved reflux esophagitis endoscopic grade.

Visceral obesity is a risk factor for reflux esophagitis (RE). We investigated the risk of RE according to visceral adipose tissue (VAT) measured by deep neural network architecture using computed tomography and evaluated the longitudinal association between abdominal adipose tissue changes and the disease course of RE. Individuals receiving health checkups who underwent esophagogastroduodenoscopy (EGD) and abdominal computed tomography (CT) at Seoul National University Healthcare System Gangnam Center between 2015 and 2016 were included. Visceral and subcutaneous adipose tissue areas and volumes were measured using a deep neural network architecture and CT. The association between the abdominal adipose tissue area and volume and the risk of RE was evaluated. Participants who underwent follow-up EGD and abdominal CT were selected; the effects of changes in abdominal adipose tissue area and volume on RE endoscopic grade were investigated using Cox proportional hazards regression. We enrolled 6570 patients who underwent EGD and abdomen CT on the same day. RE was associated with male sex, hypertension, diabetes, excessive alcohol intake, current smoking status, and levels of physical activity. The VAT area and volume increased the risk of RE dose-dependently. A decreasing VAT volume was significantly associated with improvement in RE endoscopic grade (HR:3.22, 95%CI:1.82-5.71). Changes in subcutaneous adipose tissue volume and the disease course of RE were not significantly correlated. Visceral obesity is strongly associated with RE. VAT volume reduction was prospectively associated with improvement in RE endoscopic grade dose-dependently. Visceral obesity is a potential target for RE treatment.

Breastfeeding duration is associated with favorable body composition and lower glycoprotein acetyls in later life.

The aim of the present study was to investigate associations between lifetime breastfeeding behaviors and cardiovascular risk in later reproductive years. This was a prospective 10-year longitudinal cohort study of 168 parous women. Health, lifestyle and infant feeding questionnaires, blood samples, anthropometry and body composition were collected. Cardiovascular risk was estimated using QRISK®3 and hierarchical multiple linear regression analysis performed. Mean age was 42.4 years (SD 3.8; range 31-50) and 98.7% (n = 156/158) were premenopausal. Ever breastfeeding rates were 72.6% (n = 122/168) and 37.5% (n = 63/168) lifetime ≥12 months breastfeeding duration. Median durations were 5.5 weeks for exclusive breastfeeding (IQR 35.8; range 0-190) and 30.5 weeks for any breastfeeding (IQR 84.0; range 0-488). Breastfeeding duration was not associated with QRISK®3 scores in adjusted models. Lower glycoprotein acetyls were associated with ever breastfeeding (P = 0.03), and lifetime breastfeeding ≥12 months (P = 0.001). Lifetime breastfeeding ≥12 months and longer exclusive breastfeeding were associated with lower fat mass index (P = 0.03, P = 0.01), tissue percentage fat (P = 0.02, P = 0.009) and visceral adipose tissue volume (P = 0.04, P = 0.025) after correcting for confounders including body mass index. Longer breastfeeding is associated with favorable body composition and lower glycoprotein acetyls, a novel inflammatory biomarker associated with cardiometabolic risk. Breastfeeding is a low-cost, health promoting behavior for women and infants. Pregnant women, especially those at higher risk of cardiovascular disease, should be counseled about the potential benefits of exclusive and longer breastfeeding duration.

Pre-operative visceral adipose tissue radiodensity is a potentially novel prognostic biomarker for early endoscopic post-operative recurrence in Crohn's disease.

Evidence suggests inflammatory mesenteric fat is involved in post-operative recurrence (POR) of Crohn's disease (CD). However, its prognostic value is uncertain, in part, due to difficulties studying it non-invasively. To evaluate the prognostic value of pre-operative radiographic mesenteric parameters for early endoscopic POR (ePOR). We conducted a retrospective cohort study of CD subjects ≥ 12 years who underwent ileocecal or small bowel resection between 1/1/2007 to 12/31/2021 with computerized tomography abdomen/pelvis ≤ 6 months pre-operatively and underwent ileocolonoscopy ≤ 15 months post-operatively. Visceral adipose tissue (VAT) volume (cm3), ratio of VAT:subcutaneous adipose tissue (SAT) volume, VAT radiodensity, and ratio of VAT:SAT radiodensity were generated semiautomatically. Mesenteric lymphadenopathy (LAD, largest lymph node > 10 mm) and severe vasa recta (VR) engorgement (diameter of the VR supplying diseased bowel ≥ 2 × VR supplying healthy bowel) were derived manually. The primary outcome was early ePOR (Rutgeert's score ≥ i2 on first endoscopy ≤ 15 months post-operatively) and the secondary outcome was ePOR severity (Rutgeert's score i0-4). Regression analyses were performed adjusting for demographic and disease-related characteristics to calculate adjusted odds ratio (aOR) and 95% confidence interval (CI). Of the 139 subjects included, 45% of subjects developed early ePOR (n = 63). VAT radiodensity (aOR 0.59, 95%CI: 0.38-0.90) and VAT:SAT radiodensity (aOR 8.54, 95%CI: 1.48-49.28) were associated with early ePOR, whereas, VAT volume (aOR 1.23, 95%CI: 0.78-1.95), VAT:SAT volume (aOR 0.80, 95%CI: 0.53-1.20), severe VR engorgement (aOR 1.53, 95%CI: 0.64-3.66), and mesenteric LAD (aOR 1.59, 95%CI: 0.67-3.79) were not. Similar results were observed for severity of ePOR. VAT radiodensity is potentially a novel non-invasive prognostic imaging marker to help risk stratify CD patients for POR.

Associations of MRI-derived kidney volume, kidney function, body composition and physical performance in ≈38000 UK Biobank participants: a population-based observational study.

Kidney volume is used as a predictive and therapeutic marker for several clinical conditions. However, there is a lack of large-scale studies examining the relationship between kidney volume and various clinicodemographic factors, including kidney function, body composition and physical performance. In this observational study, MRI-derived kidney volume measurements from 38526 UK Biobank participants were analysed. Major kidney volume-related measures included body surface area (BSA)-adjusted total kidney volume (TKV) and the difference in bilateral kidneys. Multivariable-adjusted linear regression and cubic spline analyses were used to explore the association between kidney volume-related measures and clinicodemographic factors. Cox or logistic regression was used to identify the risks of death, non-kidney cancer, myocardial infarction, ischaemic stroke and chronic kidney disease (CKD). The median of BSA-adjusted TKV and the difference in kidney volume were 141.9ml/m2 [interquartile range (IQR) 128.1-156.9] and 1.08-fold (IQR 1.04-1.15), respectively. Higher BSA-adjusted TKV was significantly associated with higher estimated glomerular filtration rate {eGFR; β=0.43 [95% confidence interval (CI) 0.42-0.44]; P<.001}, greater muscle volume [β=0.50 (95% CI 0.48-0.51); P<.001] and greater mean handgrip strength [β=0.15 (95% CI 0.13-0.16); P<.001] but lower visceral adipose tissue volume [VAT; β=-0.09 (95% CI -0.11 to -0.07); P<.001] in adjusted models. A greater difference in bilateral kidney volumes was associated with lower eGFR, muscle volume and physical performance but with higher proteinuria and VAT. Higher BSA-adjusted TKV was significantly associated with a reduced risk of CKD [odds ratio (OR) 0.7 (95% CI 0.63-0.77); P<.001], while a greater difference in kidney volume was significantly associated with an increased risk of CKD [OR 1.13 (95% CI 1.07-1.20); P<.001]. Higher BSA-adjusted TKV and lower differences in bilateral kidney volumes are associated with higher kidney function, muscle volume and physical performance and a reduced risk of CKD.

Cardiovascular Significance and Genetics of Epicardial and Pericardial Adiposity

Epicardial and pericardial adipose tissue (EPAT) has been associated with cardiovascular diseases such as atrial fibrillation or flutter (AF) and coronary artery disease (CAD), but studies have been limited in sample size or drawn from selected populations. It has been suggested that the association between EPAT and cardiovascular disease could be mediated by local or paracrine effects. To evaluate the association of EPAT with prevalent and incident cardiovascular disease and to elucidate the genetic basis of EPAT in a large population cohort. A deep learning model was trained to quantify EPAT area from 4-chamber magnetic resonance images using semantic segmentation. Cross-sectional and prospective cardiovascular disease associations were evaluated, controlling for sex and age. Prospective associations were additionally controlled for abdominal visceral adipose tissue (VAT) volumes. A genome-wide association study was performed, and a polygenic score (PGS) for EPAT was examined in independent FinnGen cohort study participants. Data analyses were conducted from March 2022 to December 2023. The primary exposures were magnetic resonance imaging-derived continuous measurements of epicardial and pericardial adipose tissue area and visceral adipose tissue volume. Prevalent and incident CAD, AF, heart failure (HF), stroke, and type 2 diabetes (T2D). After exclusions, this study included 44 475 participants (mean [SD] age, 64.1 [7.7] years; 22 972 female [51.7%]) from the UK Biobank. Cross-sectional and prospective cardiovascular disease associations were evaluated for a mean (SD) of 3.2 (1.5) years of follow-up. Prospective associations were additionally controlled for abdominal VAT volumes for 38 527 participants. A PGS for EPAT was examined in 453 733 independent FinnGen cohort study participants. EPAT was positively associated with male sex (β = +0.78 SD in EPAT; P < 3 × 10-324), age (Pearson r = 0.15; P = 9.3 × 10-229), body mass index (Pearson r = 0.47; P < 3 × 10-324), and VAT (Pearson r = 0.72; P < 3 × 10-324). EPAT was more elevated in prevalent HF (β = +0.46 SD units) and T2D (β = +0.56) than in CAD (β = +0.23) or AF (β = +0.18). EPAT was associated with incident HF (hazard ratio [HR], 1.29 per +1 SD in EPAT; 95% CI, 1.17-1.43), T2D (HR, 1.63; 95% CI, 1.51-1.76), and CAD (HR, 1.19; 95% CI, 1.11-1.28). However, the associations were no longer significant when controlling for VAT. Seven genetic loci were identified for EPAT, implicating transcriptional regulators of adipocyte morphology and brown adipogenesis (EBF1, EBF2, and CEBPA) and regulators of visceral adiposity (WARS2 and TRIB2). The EPAT PGS was associated with T2D (odds ratio [OR], 1.06; 95% CI, 1.05-1.07; P =3.6 × 10-44), HF (OR, 1.05; 95% CI, 1.04-1.06; P =4.8 × 10-15), CAD (OR, 1.04; 95% CI, 1.03-1.05; P =1.4 × 10-17), AF (OR, 1.04; 95% CI, 1.03-1.06; P =7.6 × 10-12), and stroke in FinnGen (OR, 1.02; 95% CI, 1.01-1.03; P =3.5 × 10-3) per 1 SD in PGS. Results of this cohort study suggest that epicardial and pericardial adiposity was associated with incident cardiovascular diseases, but this may largely reflect a metabolically unhealthy adiposity phenotype similar to abdominal visceral adiposity.

Radiological biomarkers reflecting visceral fat distribution help distinguish inflammatory bowel disease subtypes: a multicenter cross-sectional study

ObjectivesTo achieve automated quantification of visceral adipose tissue (VAT) distribution in CT images and screen out parameters with discriminative value for inflammatory bowel disease (IBD) subtypes.MethodsThis retrospective multicenter study included Crohn’s disease (CD) and ulcerative colitis (UC) patients from three institutions between 2012 and 2021, with patients with acute appendicitis as controls. An automatic VAT segmentation algorithm was developed using abdominal CT scans. The VAT volume, as well as the coefficient of variation (CV) of areas within the lumbar region, was calculated. Binary logistic regression and receiver operating characteristic analysis was performed to evaluate the potential of indicators to distinguish between IBD subtypes.ResultsThe study included 772 patients (365 CDs, median age [inter-quartile range] = 31.0. (25.0, 42.0) years, 255 males; 241 UCs, 46.0 (34.0, 55.5) years, 138 males; 166 controls, 40.0 (29.0, 53.0) years, 80 males). CD patients had lower VAT volume (CD = 1584.95 ± 1128.31 cm3, UC = 1855.30 ± 1326.12 cm3, controls = 2470.91 ± 1646.42 cm3) but a higher CV (CD = 29.42 ± 15.54 %, p = 0.006 and p ˂ 0.001) compared to UC and controls (25.69 ± 12.61 % vs. 23.42 ± 15.62 %, p = 0.11). Multivariate analysis showed CV was a significant predictor for CD (odds ratio = 6.05 (1.17, 31.12), p = 0.03). The inclusion of CV improved diagnostic efficiency (AUC = 0.811 (0.774, 0.844) vs. 0.803 (0.766, 0.836), p = 0.08).ConclusionCT-based VAT distribution can serve as a potential biomarker for distinguishing IBD subtypes.Critical relevance statementVisceral fat distribution features extracted from CT images using an automated segmentation algorithm (1.14 min) show differences between Crohn’s disease and ulcerative colitis and are promising for practical radiological screening.Key points• Radiological parameters reflecting visceral fat distribution were extracted for the discrimination of Crohn’s disease (CD) and ulcerative colitis (UC).• In CD, visceral fat was concentrated in the lower lumbar vertebrae, and the coefficient of variation was a significant predictor (OR = 6.05 (1.17, 31.12), p = 0.03).• The differences between CD, UC, and controls are promising for practical radiological screening.Graphical

Clinical and imaging features of women with polygenic partial lipodystrophy: a case series.

Familial partial lipodystrophy (FPLD) is an inherited disorder of white adipose tissue that causes premature cardiometabolic disease. There is no clear diagnostic criteria for FPLD, and this may explain the under-detection of this condition. This pilot study aimed to describe the clinical features of women with FPLD and to explore the value of adipose tissue measurements that could be useful in diagnosis. In 8 women with FPLD and 4 controls, skinfold measurements, DXA and whole-body MRI were undertaken. Whole genome sequencing was negative for monogenic metabolic causes, but polygenic scores for partial lipodystrophy were elevated in keeping with FPLD type 1. The mean age of diagnosis of DM was 31 years in the FPLD group. Compared with controls, the FPLD group had increased HOMA-IR (10.3 vs 2.9, p = 0.028) and lower mean thigh skinfold thickness (19.5 mm vs 48.2 mm, p = 0.008). The FPLD group had lower percentage of leg fat and an increased ratio of trunk to leg fat percentage on DXA. By MRI, the FPLD group had decreased subcutaneous adipose tissue (SAT) volume in the femoral and calf regions (p < 0.01); abdominal SAT, visceral adipose tissue, and femoral and calf muscle volumes were not different from controls. Women with FPLD1 in Singapore have significant loss of adipose but not muscle tissue in lower limbs and have early onset of diabetes. Reduced thigh skinfold, and increased ratio of trunk to leg fat percentage on DXA are potentially clinically useful markers to identify FPLD1.

Epicardial and pericoronary adipose tissue and coronary plaque burden in patients with Cushing's syndrome: a propensity score-matched study.

To assess coronary inflammation by measuring the volume and density of the epicardial adipose tissue (EAT), perivascular fat attenuation index (FAI) and coronary plaque burden in patients with Cushing's syndrome (CS) based on coronary computed tomography angiography (CCTA). This study included 29 patients with CS and 58 matched patients without CS who underwent CCTA. The EAT volume, EAT density, FAI and coronary plaque burden were measured. The high-risk plaque (HRP) was also evaluated. CS duration from diagnosis, 24-h urinary free cortisol (UFC), and abdominal visceral adipose tissue volume (VAT) of CS patients were recorded. The CS group had higher EAT volume (146.9 [115.4, 184.2] vs. 119.6 [69.0, 147.1] mL, P = 0.006), lower EAT density (- 78.79 ± 5.89 vs. - 75.98 ± 6.03 HU, P = 0.042), lower FAI (- 84.0 ± 8.92 vs. - 79.40 ± 10.04 HU, P = 0.038), higher total plaque volume (88.81 [36.26, 522.5] vs. 44.45 [0, 198.16] mL, P = 0.010) and more HRP plaques (7.3% vs. 1.8%, P = 0.026) than the controls. The multivariate analysis suggested that CS itself (β [95% CI], 29.233 [10.436, 48.03], P = 0.014), CS duration (β [95% CI], 0.176 [0.185, 4.242], P = 0.033), and UFC (β [95% CI], 0.197 [1.803, 19.719], P = 0.019) were strongly associated with EAT volume but not EAT density, and EAT volume (β [95% CI] - 0.037[- 0.058, - 0.016], P = 0.001) not CS was strongly associated with EAT density. EAT volume, FAI and plaque burden increased (all P < 0.05) in 6 CS patients with follow-up CCTA. The EAT volume had a moderate correlation with abdominal VAT volume (r = 0.526, P = 0.008) in CS patients. Patients with CS have higher EAT volume and coronary plaque burden but less inflammation as detected by EAT density and FAI. The EAT density is associated with EAT volume but not CS itself.

Automated abdominal adipose tissue segmentation and volume quantification on longitudinal MRI using 3D convolutional neural networks with multi-contrast inputs.

Increased subcutaneous and visceral adipose tissue (SAT/VAT) volume is associated with risk for cardiometabolic diseases. This work aimed to develop and evaluate automated abdominal SAT/VAT segmentation on longitudinal MRI in adults with overweight/obesity using attention-based competitive dense (ACD) 3D U-Net and 3D nnU-Net with full field-of-view volumetric multi-contrast inputs. 920 adults with overweight/obesity were scanned twice at multiple 3T MRI scanners and institutions. The first scan was divided into training/validation/testing sets (n = 646/92/182). The second scan from the subjects in the testing set was used to evaluate the generalizability for longitudinal analysis. Segmentation performance was assessed by measuring Dice scores (DICE-SAT, DICE-VAT), false negatives (FN), and false positives (FP). Volume agreement was assessed using the intraclass correlation coefficient (ICC). ACD 3D U-Net achieved rapid (< 4.8s/subject) segmentation with high DICE-SAT (median ≥ 0.994) and DICE-VAT (median ≥ 0.976), small FN (median ≤ 0.7%), and FP (median ≤ 1.1%). 3D nnU-Net yielded rapid (< 2.5s/subject) segmentation with similar DICE-SAT (median ≥ 0.992), DICE-VAT (median ≥ 0.979), FN (median ≤ 1.1%) and FP (median ≤ 1.2%). Both models yielded excellent agreement in SAT/VAT volume versus reference measurements (ICC > 0.997) in longitudinal analysis. ACD 3D U-Net and 3D nnU-Net can be automated tools to quantify abdominal SAT/VAT volume rapidly, accurately, and longitudinally in adults with overweight/obesity.

Effect of β-casein A1 or A2 milk on body composition, milk intake, and growth in Holstein, Simmental, and crossbred dairy calves of both sexes

The aim of this study was to compare the effects of feeding homozygous β-casein A1 or A2 milk, on the body composition, milk intake, and growth of German Holstein (GH), German Simmental (GS), and crossbred dairy calves of both sexes during the first 2 weeks of life. A total of 104 calves (n = 54 female - f and n = 50 male - m) from the breed groups GH (n = 23), GS (n = 61), and crossbred GH x GS (CR; n = 20) were evaluated. Calves were weighed after birth and received colostrum ad libitum. On the second day, calves were alternately housed in pairs in double-igloo systems according to their random birth order and received either A1 milk (n = 52; 27 f / 25 m) or A2 milk (n = 52; 27 f / 25 m). They were offered 7.5 L/day, and the individual actual total milk intake (TMI) was recorded. Daily energy-corrected milk intake was also calculated based on the milk composition (fat and protein). Fecal scores were recorded daily. On d 15, visceral adipose tissue (VAT) volume was assessed by open magnetic resonance imaging (MRI) and dual-energy x-ray absorptiometry (DXA). In addition, fat and lean mass (g), as well as bone mineral content (g) and bone mineral density (g/cm2), were determined by DXA. The body composition, milk intake, and growth were similar between the 2 types of milk in the first 2 weeks of life. Female calves had more VAT and fat mass, but less lean mass than male calves. GH and CR calves had more VAT and less lean mass than GS calves. Male calves were heavier than female calves after birth and on d 15. The average days with diarrhea and diarrhea occurrence were similar between calves fed A1 and A2 milk and between both sex groups. GS calves presented slightly more days with diarrhea and increased odds of having diarrhea compared with GH calves, not differing from CR.

Visceral adipose tissue volume effect in Crohn's disease using reduced exposure CT enterography.

The purpose of this investigation was to assess the effect of visceral adipose tissue volume (VA) on reader efficacy in diagnosing and characterizing small bowel Crohn's disease using lower exposure CT enterography (CTE). Secondarily, we investigated the effect of lower exposure and VA on reader diagnostic confidence. Prospective paired investigation of 256 CTE, 129 with Crohn's disease, were reconstructed at 100% and simulated 50% and 30% exposure. The senior author provided the disease classification for the 129 patients with Crohn's disease. Patient VA was measured, and exams were evaluated by six readers for presence or absence of Crohn's disease and phenotype using a 0-10-point scale. Logistic regression models assessed the effect of VA on sensitivity and specificity. The effect of VA on sensitivity was significantly reduced at 30% exposure (odds radio [OR]: 1.00) compared to 100% exposure (OR: 1.12) (p=0.048). There was no statistically significant difference among the exposures with respect to the effect of visceral fat on specificity (p=0.159). The study readers' probability of agreement with the senior author on disease classification was 60%, 56%, and 53% at 100%, 50%, and 30% exposure, respectively (p=0.004). When detecting low severity Crohn's disease, readers' mean sensitivity was 83%, 75%, and 74% at 100%, 50%, and 30% exposure, respectively (p=0.002). In low severity disease, sensitivity also tended to increase as visceral fat increased (ORs per 1000 cm3 increase in visceral fat: 1.32, 1.31, and 1.18, p=0.010, 0.016, and 0.100, at 100%, 50%, and 30% exposure). While the interaction is complex, VA plays a role in detecting and characterizing small bowel Crohn's disease when exposure is altered, particularly in low severity disease.

ВЗАИМОСВЯЗЬ УРОВНЯ ПРОВОСПАЛИТЕЛЬНЫХ АДИПОЦИТОКИНОВ И ОБЪЕМНО-ЛИНЕЙНЫХ ПАРАМЕТРОВ ЭКТОПИЧЕСКИХ ЖИРОВОГО ДЕПО У БОЛЬНЫХ С ИШЕМИЧЕСКОЙ БОЛЕЗНЬЮ СЕРДЦА

Abstract. Introduction. Multispiral computed angiography of the coronary arteries is the method of choice for the early noninvasive diagnosis of coronary atherosclerosis and, therefore, coronary heart disease. Quantitative indicators of epicardial fat depot are significantly associated with coronary atherosclerosis and coupled with possible cardiovascular events without reference to traditional risk factors. Aim of this study was to establish the relationship between the proinflammatory adipocytokine levels and the volumetric-linear parameters of paracardial fat depots in patients with coronary atherosclerosis. Materials and Methods. 135 patients (74 men (52%) and 61 women (48%)) with confirmed and suspected coronary heart disease were examined, aged 45 to 80 years. All patients were divided into 2 groups: Study group and comparison group. The study group consisted of 88 patients with coronary atherosclerosis, 56 men (63%) and 32 women (37%). This group included patients with one-, two- and multivessel coronary artery lesions, as well as with hemodynamically insignificant (CAD-RADs≤2) and significant (CAD-RADs≥3) stenosis areas. The comparison group consisted of 47 patients without coronary atherosclerosis. Quantitative indicators of cardiac and abdominal fat depots were calculated for all patients by means of computed tomography. Results and Discussion. The volume of epicardial adipose tissue was significantly higher in individuals with coronary heart disease, as compared to patients in the comparison group. The volume of abdominal adipose tissue was also higher in patients of the main group (p&lt;0.001). The volume of visceral adipose tissue in patients with ischemic heart disease was 1.43 times larger than in the comparison group (p&lt;0.05), the area of epicardial adipose tissue did not statistically differ in the two groups (p˃0.05), and the area of visceral adipose tissue was 1.62 times (p&lt;0.05) larger in patients with ischemic heart disease. Differences in the groups with hemodynamically insignificant and significant coronary artery stenoses were statistically valid (p˂0.05). Conclusions. In patients with coronary artery disease, the degree of increase in epicardial and abdominal fat correlates with the severity of coronary artery atherosclerosis. Laboratory tests of the adipokine-cytokine profiles is an important prognostic factor of coronary atherosclerosis severity.

Versatile MRI acquisition and processing protocol for population‐based neuroimaging

AbstractBackgroundNeuroimaging plays an essential role in epidemiological studies and a special focus is directed towards the employment of versatile MRI acquisition and processing. The proposed multi‐purpose MRI protocol was designed for large‐scale and long‐term population neuroimaging and includes structural, diffusion‐weighted, and functional MRI modalities. It directly links the acquisition of an extensive set of MRI contrasts with fully automated data processing pipelines and quality assurance of the MRI data and image‐derived phenotypes.MethodThe MRI acquisition protocol is largely based on in‐house developed MR sequences. With a total scan time below one hour per participant, it allows to acquire multiple MR contrasts at 3T with whole‐brain coverage and high isotropic image resolution, while keeping potential subject discomfort and motion artifacts at manageable levels. Designed to be kept constant, but also adaptive, the scan protocol separates into a core imaging protocol with MR contrasts of high relevance acquired for all study participants, and a free protocol to accommodate alternative promising MRI techniques in smaller sub‐populations. The analysis protocol handles large‐scale imaging data by means of fast and fully automated processing pipelines that incorporate state‐of‐the‐art image analysis tools and innovative machine learning methods, particularly using deep learning. Dedicated quality assessment (QA) includes visual rating and inspection for incidental findings on structural MRI and QA workflows tailored for each postprocessing pipeline to automatically identify problematic data based on the distribution of subject‐specific QA metrics with respect to the population average.ResultThe MRI protocol has been successfully applied in the Rhineland Study, a prospective cohort study in Bonn, Germany, with currently over 10,000 participants. Image‐derived phenotypes include: global and regional brain tissue volume, thickness and surface measures from multi‐modal structural MRI, global and regional microstructural measures based on diffusion‐weighted MRI, brain functional connectivity using resting‐state functional MRI, and volumes of subcutaneous and visceral adipose tissue based on a single‐breathhold abdominal MRI (Figure 1).ConclusionWe present a versatile MRI protocol with acquisition and analysis methods that are generally applicable and not geared towards a specific disease or research question. Thus, this protocol may be of specific interest for many neuroimaging applications including population imaging studies.

COVID-19 et obésité : quel rôle du tissu adipeux ?: COVID-19 and obesity: is there a role for adipose tissue?

In March 2020, coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 was declared a global pandemic by the WHO. Obesity was rapidly identified as an independent risk factor for poor prognosis, with an increased risk of acute respiratory distress syndrome, cardiovascular and thrombo-embolic events, admission to intensive care and mortality. The white visceral adipose tissue, which increases in people suffering from obesity, appears to have a key role in this pathogenesis, as it constitutes a viral reservoir for SARS-CoV-2 through angiotensin 2-converting enzyme receptors. Following infection of host cells, activation of pro-inflammatory cytokines creates an environment suitable to the ‘cytokine storm’ and macrophage activation syndrome, associated with a risk of progression to acute respiratory distress syndrome. In obesity, the systemic spread of the virus, its entry and prolonged excretion into already inflamed adipose tissue can stimulate immune responses and the subsequent amplification of a cytokine cascade, worsening the course of the disease. The endothelial hyperactivation induced by SARS-CoV-2 combined with the state of hypofibrinolysis and endothelial dysfunction present in obesity increases the risk of thrombo-embolic events. The volume of visceral and epicardial adipose tissue measured by CT scan appears to be a good prognostic marker for these unfavorable outcomes. In addition, vaccine responses appear to be lower in these patients due to a weaker early humoral response, which means that prevention messages need to continue to be disseminated and booster vaccinations encouraged in this population. The aim of this review is to determine the role of adipose tissue in the poor prognosis of obese patients infected with SARS-CoV-2.© 2023 Société francophone nutrition clinique et métabolisme (SFNCM).Published by Elsevier Masson SAS. All rights reserved.

Versatile MRI acquisition and processing protocol for population‐based neuroimaging

AbstractBackgroundNeuroimaging plays an essential role in epidemiological studies and a special focus is directed towards the employment of versatile MRI acquisition and processing. The proposed multi‐purpose MRI protocol was designed for large‐scale and long‐term population neuroimaging and includes structural, diffusion‐weighted, and functional MRI modalities. It directly links the acquisition of an extensive set of MRI contrasts with fully automated data processing pipelines and quality assurance of the MRI data and image‐derived phenotypes.MethodThe MRI acquisition protocol is largely based on in‐house developed MR sequences. With a total scan time below one hour per participant, it allows to acquire multiple MR contrasts at 3T with whole‐brain coverage and high isotropic image resolution, while keeping potential subject discomfort and motion artifacts at manageable levels. Designed to be kept constant, but also adaptive, the scan protocol separates into a core imaging protocol with MR contrasts of high relevance acquired for all study participants, and a free protocol to accommodate alternative promising MRI techniques in smaller sub‐populations. The analysis protocol handles large‐scale imaging data by means of fast and fully automated processing pipelines that incorporate state‐of‐the‐art image analysis tools and innovative machine learning methods, particularly using deep learning. Dedicated quality assessment (QA) includes visual rating and inspection for incidental findings on structural MRI and QA workflows tailored for each postprocessing pipeline to automatically identify problematic data based on the distribution of subject‐specific QA metrics with respect to the population average.ResultThe MRI protocol has been successfully applied in the Rhineland Study, a prospective cohort study in Bonn, Germany, with currently over 10,000 participants. Image‐derived phenotypes include: global and regional brain tissue volume, thickness and surface measures from multi‐modal structural MRI, global and regional microstructural measures based on diffusion‐weighted MRI, brain functional connectivity using resting‐state functional MRI, and volumes of subcutaneous and visceral adipose tissue based on a single‐breathhold abdominal MRI (Figure 1).ConclusionWe present a versatile MRI protocol with acquisition and analysis methods that are generally applicable and not geared towards a specific disease or research question. Thus, this protocol may be of specific interest for many neuroimaging applications including population imaging studies.

Exploring a simplified way to diagnose pelvic lipomatosis: prediction of pelvic fat volume using a single cross-sectional image.

Pelvic lipomatosis (PL) is a rare disease characterized by the overgrowth of pelvic adipose tissue (AT). We investigated the relationships between areas of subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) and pelvic fat volume (PFV), and analyzed the feasibility of diagnosing PL from a single cross-sectional image. The study included 50 patients and 50 controls. We used nnU-Net to segment SAT and VAT automatically. L3 vertebra was set as the zero point (L0), and a total of 201 slices were obtained with a 1 mm interval (L-100 - L+100). We selected 5 pelvic slices, including slices of the anterior superior margin of the S1-S4 vertebrae and the slice above the bilateral femoral head (FH). SAT areas, VAT areas, and PFVs were calculated by computational software. Areas and volumes of 2 groups were compared by t-test or rank-sum test. The correlations among areas and PFV were calculated. Logistic regression models were developed to identify the best slice for predicting PL. Receiver operating characteristic (ROC) curves were performed, and the area under the curve (AUC) and thresholds [with sensitivity (SEN) and specificity (SPE)] were calculated. VAT areas of L-94 - L-100, L+79 - L+100, S1-S4, and FH indicated statistical differences between patients and controls (P<0.05). The linear regression model with VAT area as the independent variable was established to estimate PFV (FH level: r=0.745, P<0.001, R2=0.555). Among the univariate logistic regression models, VAT area at FH as the independent variable had the highest performance in predicting PL (AUC: 0.893, SEN: 74%, SPE: 94%), followed by S4 level (AUC: 0.800, SEN: 88%, SPE: 66%). The overall accuracy of the logistic regression model including VAT areas at S4 and FH in predicting PL was 88% (AUC: 0.927, SEN: 90%, SPE: 88%). VAT areas at the level of FH can help estimate the value of PFV. VAT areas of S4 and FH provide greater power than a single image for the diagnosis of PL.

CT-based measurement of visceral adipose tissue volume as a reliable tool for assessing metabolic risk factors in prediabetes across subtypes

Visceral adipose tissue (VAT) is a well-established risk factor for the development of diabetes in individuals with prediabetes. We aimed to evaluate various adiposity and metabolic indices, including visceral adipose tissue (VAT) volume measured by CT, in individuals with prediabetes, based on their different subtypes. This retrospective study included 78 prediabetes individuals aged ≥ 20 years whose VAT volumes were evaluated by CT. Individuals were classified into prediabetes subtypes: impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and combined IFG and IGT (C-IFG/IGT). We conducted a comparison of the patients’ adiposity indices and their associations with one other, as well as with insulin resistance, based on the different prediabetes subtypes. Individuals with C-IFG/IGT had higher levels of visceral obesity than those with IFG or IGT. VAT volume was more strongly associated with insulin resistance than other adiposity indices, regardless of prediabetes subtypes. Additionally, VAT volume and liver attenuation index showed a significant correlation with the other indices studied across the prediabetes subtypes. CT-based measurement of VAT volume may be a valuable tool for evaluating metabolic risk factors among individuals with prediabetes.

The causal relationship between air pollution, obesity, and COVID-19 risk: a large-scale genetic correlation study.

Observational evidence reported that air pollution is a significant risk element for numerous health problems, such as obesity and coronavirus disease 2019 (COVID-19), but their causal relationship is currently unknown. Our objective was to probe the causal relationship between air pollution, obesity, and COVID-19 and to explore whether obesity mediates this association. We obtained instrumental variables strongly correlated to air pollutants [PM2.5, nitrogen dioxide (NO2) and nitrogen oxides (NOx)], 9 obesity-related traits (abdominal subcutaneous adipose tissue volume, waist-to-hip ratio, body mass index, hip circumference, waist circumference, obesity class 1-3, visceral adipose tissue volume), and COVID-19 phenotypes (susceptibility, hospitalization, severity) from public genome-wide association studies. We used clinical and genetic data from different public biological databases and performed analysis by two-sample and two-step Mendelian randomization. PM2.5 genetically correlated with 5 obesity-related traits, which obesity class 1 was most affected (beta = 0.38, 95% CI = 0.11 - 0.65, p = 6.31E-3). NO2 genetically correlated with 3 obesity-related traits, which obesity class 1 was also most affected (beta = 0.33, 95% CI = 0.055 - 0.61, p = 1.90E-2). NOx genetically correlated with 7 obesity-related traits, which obesity class 3 was most affected (beta = 1.16, 95% CI = 0.42-1.90, p = 2.10E-3). Almost all the obesity-related traits genetically increased the risks for COVID-19 phenotypes. Among them, body mass index, waist circumference, hip circumference, waist-to-hip ratio, and obesity class 1 and 2 mediated the effects of air pollutants on COVID-19 risks (p < 0.05). However, no direct causal relationship was observed between air pollution and COVID-19. Our study suggested that exposure to heavy air pollutants causally increased risks for obesity. Besides, obesity causally increased the risks for COVID-19 phenotypes. Attention needs to be paid to weight status for the population who suffer from heavy air pollution, as they are more likely to be susceptible and vulnerable to COVID-19.