Ratio of visceral-to-subcutaneous fat area predicts cardiovascular events in patients with type 2 diabetes

AIMS/INTRODUCTION

To investigate whether the ratio of visceral fat area (VFA) to subcutaneous fat area (SFA; V/S ratio) could be predictive of cardiovascular disease (CVD) as compared with VFA or SFA in patients with diabetes.

MATERIALS AND METHODS

A total of 682 patients with type 2 diabetes (mean age 64 ± 13 years; 41% women) were enrolled. VFA (cm2 ) and SFA (cm2 ) were assessed by a dual bioelectrical impedance analyzer. The patients were divided into four groups according to the quartiles of the V/S ratio. The study end-point was the first occurrence or recurrence of CVD.

RESULTS

Over a median follow up of 2.5 years, 21 patients reached the end-point. The number of patients who reached the end-point was increased along with the increasing of the V/S ratio quartiles. The V/S ratio was significantly associated with incident or recurrent CVD (hazard ratio [HR] 1.82, 95% CI: 1.09-3.04, P = 0.021) after adjusting for estimated glomerular filtration rate (HR 0.98, 95% CI: 0.96-1.00), brain-type natriuretic peptide (HR 1.00, 95% CI: 1.00-1.01), use of antiplatelet agents (HR 4.26, 95% CI: 1.63-11.13), coefficient of variation of R-R intervals (HR 0.85, 95% CI: 0.69-1.10) and glycated hemoglobin (HR 1.37, 95% CI: 1.05-1.79). The addition of the V/S ratio to age, estimated glomerular filtration rate, brain-type natriuretic peptide, antiplatelet agents and glycated hemoglobin significantly improved classification performance for CVD using net reclassification improvement (0.60, 95% CI: 0.21-1.00) and the integrated discrimination improvement (0.02, 95% CI: 0.00-0.05).

CONCLUSIONS

The V/S ratio measured by dual bioelectrical impedance analyzer is an independent predictor of CVD in patients with type 2 diabetes.

Visceral-to-subcutaneous fat ratio exhibits strongest association with early post-operative outcomes in patients undergoing surgery for advanced rectal cancer

AIM

Despite their promise as prognostic factors in colorectal cancer, anthropometric data are frequently contradictory or difficult to interpret, with single body-composition parameters often investigated in isolation or heterogeneous clinical cohorts used in analyses. We sought to assess a spectrum of body-composition parameters in a highly selected cohort with locally advanced rectal cancer in a bid to determine those with strongest prognostic potential in this specific setting.

MATERIALS/METHODS

Between 2014 and 2020, 78 individuals received neoadjuvant chemotherapy, or chemoradiotherapy, followed by radical surgery in the treatment of locally advanced rectal adenocarcinoma at Oxford University Hospitals Trust. Demographic, treatment-related, perioperative, and short-term outcomes data were assessed. Body-composition parameters included BMI, and those derived from pre-operative computed-tomography imaging: skeletal mass index (SMI), visceral fat area (VFA), subcutaneous fat area (SFA), perinephric fat area (PFA) visceral-to-subcutaneous fat ratio (V/S), sarcopenia, and sarcopenic obesity (SO).

RESULTS

Pre-operative body-composition parameters exhibited particularly strong correlation with post-operative outcomes, with VFA (p = 0.002), V/S (p = 0.019), SO (p = 0.012), and PFA (p = 0.0016) all associated with an increased length of hospital stay. Univariate and multivariate analyses demonstrated V/S to be the sole independent body-composition risk factor to be associated with an increased risk of developing Clavien-Dindo complications ≥ 2 (p = 0.033) as well as an increased length of stay (p = 0.005).

CONCLUSION

Among patients with locally advanced rectal cancer, high visceral-to-subcutaneous fat ratio is the body-composition parameter most strongly associated with poor early post-operative outcomes. This should be considered in patient selection and prehabilitation protocols. WHAT DOES THIS PAPER ADD TO THE LITERATURE? : Our study demonstrates that among body composition parameters, high visceral-to-subcutaneous fat ratio is strongly associated with increased risk of post-operative complications and increased length of stay in patients undergoing surgery for advanced rectal cancer.

Low Body Mass Index Is an Independent Prognostic Factor in Patients With Non-Small Cell Lung Cancer Treated With Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor

Background

Sarcopenia and obesity have been suspected as factors associated with efficacy of treatment and prognosis in various malignancies. This study aimed to investigate the association of pretreatment sarcopenia and visceral obesity with efficacy and prognosis of first- and second-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) for patients with non-small cell lung cancer (NSCLC) and positive EGFR mutation.

Methods

We retrospectively collected 167 NSCLC patients with mutant EGFR who had started EGFR-TKI monotherapy between October 2007 and August 2018 at our hospital. We classified 167 patients into two groups, according to the definition of underweight based on the World Health Organization (WHO) body mass index (BMI) classification and the Japanese sex-specific cut-off values of the following computed tomography (CT) images-assessed markers of pretreatment sarcopenia or visceral obesity, such as psoas muscle index (PMI), intramuscular adipose tissue content (IMAC) and visceral-to-subcutaneous fat ratio (VSR) at lumbar vertebra L3 level. We compared overall survival (OS) and progression-free survival (PFS) of two groups by Kaplan-Meier curves and log-rank tests. Using multivariate Cox proportional hazard analyses adjusted by age, neutrophil-to-lymphocyte ratio, performance status, EGFR mutation types and EGFR-TKI lines, and extra-pulmonary metastases or three or more than 3 metastatic sites, we searched independent prognostic factors of OS and PFS of EGFR-TKI therapy.

Results

The OS (median 26.0 vs. 32.3 months, P = 0.02) and PFS (9.1 vs. 14.8 months, P = 0.03) of patients with BMI < 18.5 were significantly shorter than those of patients with BMI ≥ 18.5. However, there was no significant difference in OS and PFS according to PMI, IMAC and VSR. The multivariate analyses detected only BMI < 18.5 as an unfavorable prognostic factor of shorter OS (hazard ratio (HR) 1.70, 95% confidence interval (CI) 1.03 - 2.81, P = 0.04) and PFS (HR 1.72, 95% CI 1.11 - 2.67, P = 0.02).

Conclusions

Pretreatment underweight was a significant prognostic factor of poor PFS and OS of EGFR-TKI therapy. However, neither pretreatment sarcopenia nor visceral obesity was associated with prognosis of EGFR-TKI. Underweight may be a surrogate for advanced disease burden.

Tetraspanin7 in adipose tissue remodeling and its impact on metabolic health

OBJECTIVE

We previously identified tetraspanin 7 (Tspan7) as a candidate gene influencing body weight in an obesity-related gene screening study. However, the mechanisms underlying its involvement in body weight regulation remained unclear. This study aims to investigate the role of TSPAN7 from a metabolic perspective.

METHODS

We utilized genetically modified mice, including adipose tissue-specific Tspan7-knockout and Tspan7-overexpressing models, as well as human adipose-derived stem cells with TSPAN7 knockdown and overexpression. Morphological, molecular, and omics analyses, including proteomics and transcriptomics, were performed to investigate TSPAN7 function. Physiological effects were assessed by measuring blood markers associated with lipid regulation under metabolic challenges, such as high-fat feeding and aging.

RESULTS

We show that TSPAN7 is involved in regulating lipid droplet formation and stabilization. Tspan7-knockout mice exhibited an increased proportion of small-sized adipocytes and a reduced visceral-to-subcutaneous fat ratio. This shift in fat distribution was associated with improved insulin sensitivity and altered branched-chain amino acid metabolism, as evidenced by increased expression of the branched-chain α-keto acid dehydrogenase complex subunit B in Tspan7-modified mice. Mechanistically, TSPAN7 deficiency promoted subcutaneous fat expansion, alleviating metabolic stress on visceral fat, a major contributor to insulin resistance.

CONCLUSIONS

TSPAN7 influences lipid metabolism by modulating adipose tissue remodeling, particularly under metabolic challenges, such as high-fat diet exposure and aging. Its modulation enhances subcutaneous fat storage capacity while mitigating visceral fat accumulation, leading to improved insulin sensitivity. These findings position TSPAN7 as a potential target for therapeutic interventions aimed at improving metabolic health and preventing obesity-related diseases.

Comparison of Computed Tomography-based Abdominal Adiposity Indexes as Predictors of Non-alcoholic Fatty Liver Disease Among Middle-aged Korean Men and Women

Objectives:

We compared the associations of 3 computed tomography (CT)-based abdominal adiposity indexes with non-alcoholic fatty liver disease (NAFLD) among middle-aged Korean men and women.

Methods:

The participants were 1366 men and 2480 women community-dwellers aged 30-64 years. Three abdominal adiposity indexes—visceral fat area (VFA), subcutaneous fat area (SFA), and visceral-to-subcutaneous fat ratio (VSR)—were calculated from abdominal CT scans. NAFLD was determined by calculating the Liver Fat Score from comorbidities and blood tests. An NAFLD prediction model that included waist circumference (WC) as a measure of abdominal adiposity was designated as the base model, to which VFA, SFA, and VSR were added in turn. The area under the receiver operating characteristic curve (AUC), integrated discrimination improvement (IDI), and net reclassification improvement (NRI) were calculated to quantify the additional predictive value of VFA, SFA, and VSR relative to WC.

Results:

VFA and VSR were positively associated with NAFLD in both genders. SFA was not significantly associated with NAFLD in men, but it was negatively associated in women. When VFA, SFA, and VSR were added to the WC-based NAFLD prediction model, the AUC improved by 0.013 (p<0.001), 0.001 (p=0.434), and 0.009 (p=0.007) in men and by 0.044 (p<0.001), 0.017 (p<0.001), and 0.046 (p<0.001) in women, respectively. The IDI and NRI were increased the most by VFA in men and VSR in women.

Conclusions:

Using CT-based abdominal adiposity indexes in addition to WC may improve the detection of NAFLD. The best predictive indicators were VFA in men and VSR in women.