Abdominal visceral and subcutaneous adipose tissue and associations with cardiometabolic risk in Inuit, Africans and Europeans: a cross-sectional study

Ethnic differences in CT derived abdominal body composition measures: a comparative retrospect pilot study between European and Inuit study population

Understanding ethnic variations in body composition is crucial for assessing health risks. Universal models may not suit all ethnicities, and there is limited data on the Inuit population. This study aimed to compare body composition between Inuit and European adults using computed tomography (CT) scans and to investigate the influence of demographics on these measurements. A retrospective analysis was conducted on 50 adults (29 Inuit and 21 European) who underwent standard trauma CT scans. Measurements focused on skeletal muscle index (SMI), various fat indices, and densities at the third lumbar vertebra level, analyzed using the Wilcoxon-Mann-Whitney test and multiple linear regression. Inuit women showed larger fat tissue indices and lower muscle and fat densities than European women. Differences in men were less pronouncehd, with only Intramuscular fat density being lower among Inuit men. Regression indicated that SMI was higher among men, and skeletal muscle density decreased with Inuit ethnicity and age, while visceral fat index was positively associated with age. This study suggests ethnic differences in body composition measures particularly among women, and indicates the need for Inuit-specific body composition models. It higlights the importance of further research into Inuit-specific body composition measurements for better health risk assessment.

Associations of early childhood body mass index trajectories with body composition and cardiometabolic markers at age 10 years: the Ethiopian infant anthropometry and body composition (iABC) birth cohort study

BACKGROUND

Variability in body mass index (BMI) (kg/m2) trajectories is associated with body composition and cardiometabolic markers in early childhood, but it is unknown how these associations track to later childhood.

OBJECTIVES

We aimed to assess associations of BMI trajectories from 0 to 5 y with body composition and cardiometabolic markers at 10 y.

METHODS

In the Ethiopian infant anthropometry and body composition (iABC) birth cohort, we previously identified 4 distinct BMI trajectories from 0 to 5 y: stable low BMI (19.2%), normal BMI (48.8%), rapid growth to high BMI (17.9%), and slow growth to high BMI (14.1%). At 10 y, we obtained data from 320 children on anthropometry, body composition, abdominal subcutaneous and visceral fat, and cardiometabolic markers. Associations of BMI trajectories and 10-y outcomes were analyzed using multiple linear regression.

RESULTS

Compared with children with the normal BMI trajectory, those with rapid growth to high BMI had 1.7 cm (95% CI: 0.1, 3.3) larger waist circumference and those with slow growth to high had 0.63 kg/m2 (95% CI: 0.09, 1.17) greater fat mass index and 0.19 cm (95% CI: 0.02, 0.37) greater abdominal subcutaneous fat, whereas those with stable low BMI had -0.28 kg/m2 (95% CI: -0.59, 0.03) lower fat-free mass at 10 y. Although the confidence bands were wide and included the null value, children with rapid growth to high BMI trajectory had 48.6% (95% CI: -1.4, 123.8) higher C-peptide concentration and those with slow growth to high BMI had 29.8% (95% CI: -0.8, 69.8) higher insulin and 30.3% (95% CI: -1.1, 71.6) higher homeostasis model assessment of insulin resistance, whereas those with rapid growth to high BMI had -0.23 mmol/L (95% CI: -0.47, 0.02) lower total cholesterol concentration. The trajectories were not associated with abdominal visceral fat, blood pressure, glucose, and other lipids at 10 y.

CONCLUSIONS

Children with rapid and slow growth to high BMI trajectories before 5 y tend to show higher measures of adiposity and higher concentrations of markers related to glucose metabolism at 10 y.

CLINICAL TRIAL REGISTRY

ISRCTN46718296 (https://www.isrctn.com/ISRCTN46718296).

Adiposity Phenotypes and Associated Cardiometabolic Risk Profile in the Inuit Population of Nunavik

The Inuit population of Nunavik is faced with a significant rise in the prevalence of obesity [body mass index (BMI) ≥ 30 kg/m2], but the impact on cardiometabolic health is unclear. The aim of this study was to characterize adiposity phenotypes and explore their associations with cardiometabolic risk factors among Nunavimmiut men and women. We used data obtained from 1296 Inuit who participated in the Qanuilirpitaa? 2017 Nunavik Inuit Health survey. Collected information included demographics, anthropometric measurements including visceral fat level (VFL) measured using electrical bioimpedance, biomarkers, hemodynamics, medical history and medication list. Adjusted population-weighted linear regressions were conducted to assess associations between body fat distribution and cardiometabolic risk factors. The accuracy and cut-off points of anthropometric indices to detect cardiometabolic abnormalities was evaluated by area under the receiver operator characteristic curve (AUROC) and a maximum Youden index analysis. Among Nunavimmiut (mean age 38.8 years [95%CI: 38.4 to 39.3]), obesity was observed in 42.8% of women and 25.6% of men. Compared to men, women presented a higher prevalence of abdominal obesity (78.8% vs. 46.4% in men, p < 0.05) and elevated VFL (54.4% vs. 20.1% with an InBody level ≥ 13, p < 0.05). Indices of global fat distribution and abdominal adiposity including VFL provided poor to moderate ability to detect cardiometabolic abnormalities (AUROC between 0.64 and 0.79). This analysis revealed that despite a high prevalence of abdominal obesity, particularly among women, anthropometric measurements of adiposity are inconsistently associated cardio-metabolic risk factors in Inuit adults of Nunavik.

Adipose tissue depot specific expression and regulation of fibrosis-related genes and proteins in experimental obesity

Transforming growth factor beta (Tgfb) is a well-studied pro-fibrotic cytokine, which upregulates cellular communication network factor 2 (Ccn2), collagen, and actin alpha 2, smooth muscle (Acta2) expression. Obesity induces adipose tissue fibrosis, which contributes to metabolic diseases. This work aimed to analyze the expression of Tgfb, Ccn2, collagen1a1 (Col1a1), Acta2 and BMP and activin membrane-bound inhibitor (Bambi), which is a negative regulator of Tgfb signaling, in different adipose tissue depots of mice fed a standard chow, mice fed a high fat diet (HFD) and ob/ob mice. Principally, these genes were low expressed in brown adipose tissues and this difference was less evident for the ob/ob mice. Ccn2 and Bambi protein as well as mRNA expression, and collagen1a1 mRNA were not induced in the adipose tissues upon HFD feeding whereas Tgfb and Acta2 mRNA increased in the white fat depots. Immunoblot analysis showed that Acta2 protein was higher in subcutaneous and perirenal fat of these mice. In the ob/ob mice, Ccn2 mRNA and Ccn2 protein were upregulated in the fat depots. Here, Tgfb, Acta2 and Col1a1 mRNA levels and serum Tgfb protein were increased. Acta2 protein was, however, not higher in subcutaneous and perirenal fat of these mice. Col6a1 mRNA was shown before to be higher in obese fat tissues. Current analysis proved the Col6a1 protein was induced in subcutaneous fat of HFD fed mice. Notably, Col6a1 was reduced in perirenal fat of ob/ob mice in comparison to the respective controls. 3T3-L1 cells express Ccn2 and Bambi protein, whose levels were not changed by fatty acids, leptin, lipopolysaccharide, tumor necrosis factor and interleukin-6. All of these factors led to higher Tgfb in 3T3-L1 adipocyte media but did not increase its mRNA levels. Free fatty acids induced necrosis whereas apoptosis did not occur in any of the in vitro incubations excluding cell death as a main reason for higher Tgfb in cell media. In summary, Tgfb mRNA is consistently induced in white fat tissues in obesity but this is not paralleled by a clear increase of its target genes. Moreover, discrepancies between mRNA and protein expression of Acta2 were observed. Adipocytes seemingly do not contribute to higher Tgfb mRNA levels in obesity. These cells release more Tgfb protein when challenged with obesity-related metabolites connecting metabolic dysfunction and fibrosis.

Cardiometabolic disease in Black African and Caribbean populations: an ethnic divergence in pathophysiology?

In the UK, populations of Black African and Caribbean (BAC) ethnicity suffer higher rates of cardiometabolic disease than White Europeans (WE). Obesity, leading to increased visceral adipose tissue (VAT) and intrahepatic lipid (IHL), has long been associated with cardiometabolic risk, driving insulin resistance and defective fatty acid/lipoprotein metabolism. These defects are compounded by a state of chronic low-grade inflammation, driven by dysfunctional adipose tissue. Emerging evidence has highlighted associations between central complement system components and adipose tissue, fatty acid metabolism and inflammation; it may therefore sit at the intersection of various cardiometabolic disease risk factors. However, increasing evidence suggests an ethnic divergence in pathophysiology, whereby current theories fail to explain the high rates of cardiometabolic disease in BAC populations. Lower fasting and postprandial TAG has been reported in BAC, alongside lower VAT and IHL deposition, which are paradoxical to the high rates of cardiometabolic disease exhibited by this ethnic group. Furthermore, BAC have been shown to exhibit a more anti-inflammatory profile, with lower TNF-α and greater IL-10. In contrast, recent evidence has revealed greater complement activation in BAC compared to WE, suggesting its dysregulation may play a greater role in the high rates of cardiometabolic disease experienced by this population. This review outlines the current theories of how obesity is proposed to drive cardiometabolic disease, before discussing evidence for ethnic differences in disease pathophysiology between BAC and WE populations.

Birth weight, skeletal maturity and dietary patterns are associated with body composition compartments differently in male and female physically active adolescents

Background: Adequate body composition is important for health and performance of physically active adolescents; however, some factors can influence body composition. Aim: The purpose of this study was to evaluate the association between body composition and birth weight, skeletal maturity and dietary patterns, in male (n = 124) and female (n = 107) physically active adolescents. Methods: Birth weight was obtained from health booklets. Dual-energy X-ray absorptiometry (DXA) was used to estimate fat mass (FM), fat-free mass (FFM), visceral adipose tissue (VAT) and abdominal adipose tissue (ASAT). Skeletal maturity was assessed by a hand and fist scanner using DXA. Food intake was assessed using a food frequency questionnaire and dietary patterns by factorial analysis. Results: Seventy one percent (male = 16%, female = 55%) of the participants were mature. Two dietary patterns (in natura/minimally processed and processed/ultra-processed) were identified. In males, FM (>15%, P = 0.043) and ASAT (>30%, P = 0.042) were higher in those with low-median compared to high-median birth weight. FFM (>24%) was higher in skeletally mature compared to those immatures (P = 0.001), and VAT (>28%) was higher in processed/ultra-processed compared to in natura/minimally processed dietary patterns (P = 0.015). In females, FFM (>9%) was higher in those with low-median compared to high-median birth weight (P = 0.019); and FFM (>16%), FM (>28%) and ASAT (>45%) were higher in skeletally mature compared to those immatures (P = 0.001). Conclusion: Our results may contribute to a better understanding of the complex association among body composition, birth weight, skeletal maturity and dietary patterns and in physically active adolescents, differently according to sex.

Validation of the Fatty Liver Index for identifying non-alcoholic fatty liver disease in a Kenyan population

BACKGROUND AND AIM

Fatty Liver Index (FLI) is a simple clinical scoring system estimating non-alcoholic fatty liver disease (NAFLD). It is validated in European-descent and Asian populations, but not in sub-Saharan Africans. The aim of this study is to evaluate the validity of the FLI for predicting NAFLD in a population from Kenya.

METHODS

Participants were recruited from a community-based study conducted in Kenya. NAFLD was diagnosed using hepatic ultrasonography. Clinical, anthropometrical, biochemical and lifestyle data were obtained. The accuracy and cut-off point of the FLI to detect NAFLD were evaluated by area under the receiver operator characteristic curve and the maximum Youden index analysis.

RESULTS

A total of 640 participants (94 with NAFLD) were included. Mean age was 37.4 ± 0.4 years and 58.7% were women. Mean body mass index (BMI) was 22.3 ± 0.2 kg/m2 and waist circumference (WC) 79.1 ± 0.4 cm. A total of 15 (2.3%) participants were diagnosed with type 2 diabetes and 65 (10.2%) with obesity (BMI ≥ 30 kg/m2 ). AUROC of FLI for predicting NAFLD was 0.80 (95% CI 0.74-0.85), which was significantly higher compared to individual components gamma-glutamyl transferase and triglycerides (p < 0.05), but not compared to anthropometric parameters BMI (AUROC of 0.83, 95% CI 0.79-0.88) and WC (AUROC of 0.81, 95% CI 0.76-0.87).

CONCLUSIONS

FLI is a simple valid scoring system to use in rural and urban Kenyan adults. However, this index might not be superior to BMI or WC to predict NAFLD, and those measurements might therefore be more appropriate in limited settings.

Associations of weight and body composition at birth with body composition and cardiometabolic markers in children aged 10 y: the Ethiopian infant anthropometry and body composition birth cohort study

BACKGROUND

Although birth weight (BW) has been associated with later cardiovascular disease and type 2 diabetes, the role of birth fat mass (BFM) and birth fat-free mass (BFFM) on cardiometabolic health is unclear.

OBJECTIVES

To examine associations of BW, BFM, and BFFM with later anthropometry, body composition, abdominal fat, and cardiometabolic markers.

METHODS

Birth cohort data on standardized exposure variables (BW, BFM, and BFFM) and follow-up information at age 10 y on anthropometry, body composition, abdominal fat, and cardiometabolic markers were included. A linear regression analysis was used to assess associations of exposures with outcome variables, adjusting for maternal and child characteristics at birth and current body size in separate models.

RESULTS

Among 353 children, mean (SD) age was 9.8 (1.0) y, and 51.5% were boys. In the fully adjusted model, 1-SD higher BW and BFFM were associated with 0.81 cm (95% CI: 0.21, 1.41 cm) and 1.25 cm (95% CI: 0.64, 1.85 cm) greater height at 10 y, respectively. The 1-SD higher BW and BFM were associated with 0.32 kg/m2 (95% CI: 0.14, 0.51 kg/m2) and 0.42 kg/m2 (95% CI: 0.25, 0.59 kg/m2) greater fat mass index at 10 y, respectively. In addition, 1-SD higher BW and BFFM were associated with 0.22 kg/m2 (95% CI: 0.09, 0.34 kg/m2) greater FFM index, whereas a 1-SD greater BFM was associated with a 0.05 cm greater subcutaneous adipose tissue (95% CI: 0.01, 0.11 cm). Furthermore, 1-SD higher BW and BFFM were associated with 10.3% (95% CI: 1.4%, 20.0%) and 8.3% (95% CI: -0.5%, 17.9%) greater insulin, respectively. Similarly, 1-SD higher BW and BFFM were associated with 10.0% (95% CI: 0.9%, 20.0%) and 8.5% (95% CI: -0.6%, 18.5%) greater homeostasis model assessment of insulin resistance, respectively.

CONCLUSIONS

BW and BFFM rather than BFM are predictors of height and FFM index at 10 y. Children with higher BW and BFFM showed higher insulin concentrations and homeostasis model assessment of insulin resistance at 10 y of age. This trial was registered at ISRCTN as ISRCTN46718296.

Distinct inflammatory signatures of upper and lower body adipose tissue and adipocytes in women with normal weight or obesity

Introduction

Upper and lower body fat accumulation poses an opposing obesity-related cardiometabolic disease risk. Depot-differences in subcutaneous adipose tissue (SAT) function may underlie these associations. We aimed to investigate the inflammatory signatures of abdominal (ABD) and femoral (FEM) SAT in postmenopausal women with normal weight or obesity.

Methods

We included 23 postmenopausal women with normal weight (n = 13) or obesity (n = 10). In vivo secretion of adipokines from ABD and FEM SAT was measured using the arterio-venous balance technique. Adipokine gene expression and adipocyte morphology were examined in ABD and FEM SAT. Furthermore, adipokine expression and secretion were investigated in vitro using differentiated human primary ABD and FEM subcutaneous adipocytes derived from the study participants.

Results

Plasma leptin and plasminogen activator inhibitor (PAI)-1 concentrations were higher, and ABD and FEM adipocytes were larger in women with obesity than normal weight. No differences in adipocyte size and blood flow were apparent between ABD and FEM SAT. We found significant release of leptin and monocyte chemoattractant protein (MCP)-1 from ABD and FEM SAT, with higher fractional release of MCP-1 from ABD than FEM SAT. Gene expression of leptin, PAI-1, and tumor necrosis factor-α was lower in ABD than FEM SAT and higher in women with obesity than normal weight. In ABD adipocytes, interleukin-6, PAI-1, and leptin gene expression were higher, while adiponectin and dipeptidyl-peptidase-4 gene expression were lower than in FEM adipocytes. Finally, ABD adipocytes secreted less MCP-1 compared to FEM adipocytes.

Discussion

These findings demonstrate that upper and lower body SAT and adipocytes are characterized by distinct inflammatory signatures in postmenopausal women, which seem independent of adipocyte size.

Understanding health disparities affecting people of West Central African descent in the United States: An evolutionary perspective

Human populations adapting to diverse aspects of their environment such as climate and pathogens leave signatures of genetic variation. This principle may apply to people of West Central African descent in the United States, who are at increased risk of certain chronic conditions and diseases compared to their European counterparts. Less well known is that they are also at reduced risk of other diseases. While discriminatory practices in the United States continue to affect access to and the quality of healthcare, the health disparities affecting African Americans may also be due in part to evolutionary adaptations to the original environment of sub-Saharan Africa, which involved continuous exposure to the vectors of potentially lethal endemic tropical diseases. Evidence is presented that these organisms selectively absorb vitamin A from the host, and its use in parasite reproduction contributes to the signs and symptoms of the respective diseases. These evolutionary adaptations included (1) sequestering vitamin A away from the liver to other organs, to reduce accessibility to the invaders; and (2) reducing the metabolism and catabolism of vitamin A (vA), causing it to accumulate to subtoxic concentrations and weaken the organisms, thereby reducing the risk of severe disease. However, in the environment of North America, lacking vA-absorbing parasites and with a mainly dairy-based diet that is high in vA, this combination of factors is hypothesized to lead to the accumulation of vA and to increased sensitivity to vA as a toxin, which contribute to the health disparities affecting African Americans. vA toxicity is linked to numerous acute and chronic conditions via mitochondrial dysfunction and apoptosis. Subject to testing, the hypothesis suggests that the adoption of traditional or modified West Central African-style diets that are low in vA and high in vA-absorbing fiber hold promise for disease prevention and treatment, and as a population-based strategy for health maintenance and longevity.

Correlation between insulin-based and C-peptide based homeostatic model assessment of insulin resistance in adults without diabetes in a sub-Saharan African setting: a cross-sectional study

OBJECTIVE

To assess the correlation between the insulin-based and C-peptide based HOMA-IR in the general population without diabetes in sub-Saharan Africa as well as to identify factors associated with IR.

RESULTS

This was a cross-sectional study in urban settings in Yaoundé, Cameroon. We included 84 people with a body mass index (BMI) ≥ 18.5 Kg/m² and without diabetes (females: 72.6%; mean age: 37 years). IR was assessed using the following formulae: HOMA-IR_INS = fasting insulin (mU/ml) x fasting plasma glucose (FPG) (mmol/L)/ 22.5; HOMA-IR_CP1 = fasting C-peptide (mU/ml) x FPG (mmol/L)/ 22.5; and HOMA-IR_CP2 = 1.5 + (FPG (mg/dl) x fasting C-peptide (ng/ml))/ 2800. Correlation (rho) between HOMA-IR_INS and C-peptide based HOMA-IR was investigated using the Spearman rank test. The median (25th -75th percentiles) HOMA-IR_INS, HOMA-IR_CP1, and HOMA-IR_CP2 were: 1.94 (1.36-3.50), 0.18 (0.11-0.27) and 9.91 (6.81-14.52), respectively. There was no correlation between the insulin-based and C-peptide-based HOMA-IR indices: rho = 0.043, p = 0.697. IR (HOMA-IR_INS ≥ 2.8) was associated with obesity: A BMI ≥ 30 Kg/m² (adjusted odds ratio (aOR): 16.9, 95% confidence intervals (CI): 3.1-92.5) and being a student (aOR: 8.9, 95%CI: 2.1-38.2) were associated with IR.

Correlation of vascular structural changes in a cadaveric model and obesity-related cardiovascular non-communicable diseases

INTRODUCTION

Carrying excess body weight is a vital risk factor for obesity-related chronic diseases affecting blood vessels. Obesity influences cardiovascular noncommunicable diseases (NCDs) via vascular structural changes, which involve alterations in lipids, blood pressure, coagulation, fibrinolysis, and inflammation, leading to endothelial dysfunction due to vascular remodelling and stiffness. Small peripheral vessels are the first to be impacted; however, it is unclear whether this change is followed by microscopic changes in the aorta.

OBJECTIVES

To determine the correlation of vascular structure with the incidence of NCDs and subcutaneous fat thickness and to study micro-scale changes in vascular structure, especially concerning collagen in the aorta, using a cadaveric model.

METHODS

Twenty-four cadaveric models were classified into a control group and an NCD group. The subcutaneous fat thickness was measured on the arm, anterior abdomen, and thigh. The aorta was collected and stained with haematoxylin, eosin, and Masson's trichrome for collagen evaluation. The vessel thickness was morphometrically analysed. Scanning electron microscopy was performed to identify the extracellular matrix organization in the vessel.

RESULTS

Disorganization of the extracellular matrix and fragments of the vascular wall were found in the NCDs group. The tunica intima of the NCDs group represented endothelial dysfunction with macrophage foam cells. The thickness of the tunica intima of the NCDs group slightly increased without being significantly different compared to control group with 144.63 ± 124.38 µm. and 105.60 ± 27.49 µm, respectively. However, the thickness of tunica media of the NCDs group significantly decreased compared to control group with 956.58 ± 27.80 µm. and 1167.43 ± 48.6 µm, respectively. Collagen deposits in the aortic wall significantly increased by 15% in the NCDs group especially in tunica media by 17.4% compared to control. The results showed a correlation between the amount of collagen fibre and subcutaneous fat on the thigh.

CONCLUSION

There was a change toward irregular microstructural patterns and increased collagen fibres in NCDs. In addition, there was a correlation between collagen fibre density and the subcutaneous fat thickness of the thigh in cadavers with a history of NCDs.

Association between MRI-based visceral adipose tissues and metabolic abnormality in a Chinese population: a cross-sectional study

Background

Previous studies have indicated that the deposition of abdominal adipose tissue was associated with the abnormalities of cardiometabolic components. The aim of this study was to examine the relationship of visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and metabolic status and the different effects between males and females.

Methods

The 1388 eligible subjects were recruited in a baseline survey of metabolic syndrome in China, from two communities in Hangzhou and Chengdu. Areas of abdominal VAT and SAT were measured by magnetic resonance imaging (MRI). Serum total triglycerides (TG), high-density lipoprotein cholesterol (HDL-C) were measured by an automated biochemical analyzer. Metabolic abnormality (MA) was defined more than one abnormal metabolic components, which was based on the definition of metabolic syndrome (IDF 2005). Multiple logistic regression was used to calculate the odds ratios (ORs) and 95% confidence intervals (95%CI). Predictive value was assessed by area under the curve (AUC), net reclassification improvement (NRI), and integrated discrimination improvement (IDI), respectively.

Results

Their mean age was 53.8 years (SD: 7.1 years), the mean body mass index (BMI) was 23.7 kg/m², and 44.8% of the subjects were male. Both male and female with MA had higher VAT levels compared to subjects with normal metabolism (MN), and male had higher SAT levels than female (P < 0.05). Higher VAT was significantly associated with MA with ORs in the fourth quartile (Q4) of 6.537 (95% CI = 3.394–12.591) for male and 3.364 (95% CI = 1.898–5.962) for female (P for trend < 0.05). In female, VAT could increase the risk of metabolic abnormalities, but SAT could increase the risk of MA in the second and fourth quartiles (Q2 and Q4) only at BMI > 24 kg/m². In male, VAT improved the predictive value of MA compared to BMI and waist circumference (WC), the AUC was 0.727 (95% CI = 0.687–0.767), the NRI was 0.139 (95% CI = 0.070–0.208) and 0.106 (95% CI = 0.038–0.173), and the IDI was 0.074 (95% CI = 0.053–0.095) and 0.046 (95% CI = 0.026–0.066). Similar results were found in female.

Conclusions

In male, VAT and SAT could increase the risk of metabolic abnormalities both at BMI < 24 kg/m² and at BMI ≥ 24 kg/m². In female, VAT could increase the risk of metabolic abnormalities but SAT could increase the risk of MA in the second and fourth quartiles (Q2 and Q4) only at BMI > 24 kg/m². Deposition of abdominal adipose tissue was associated with metabolic abnormalities. VAT improved the predictive power of MA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12986-022-00651-x.

Adipose Tissue Inflammation and Cardiovascular Disease: An Update

PURPOSE OF REVIEW

The obesity epidemic is on the rise, and while it is well known that obesity is associated with an increase in cardiovascular risk factors such as type 2 diabetes mellitus, hypertension, and obstructive sleep apnea, recent data has highlighted that the degree and type of fat distribution may play a bigger role in the pathogenesis of cardiovascular disease (CVD) than body mass index (BMI) alone. We aim to review updated data on adipose tissue inflammation and distribution and CVD.

RECENT FINDINGS

We review the pathophysiology of inflammation secondary to adipose tissue, the association of obesity-related adipokines and CVD, and the differences and significance of brown versus white adipose tissue. We delve into the clinical manifestations of obesity-related inflammation in CVD. We discuss the available data on heterogeneity of adipose tissue-related inflammation with a focus on subcutaneous versus visceral adipose tissue, the differential pathophysiology, and clinical CVD manifestations of adipose tissue across sex, race, and ethnicity. Finally, we present the available data on lifestyle modification, medical, and surgical therapeutics on reduction of obesity-related inflammation. Obesity leads to a state of chronic inflammation which significantly increases the risk for CVD. More research is needed to develop non-invasive VAT quantification indices such as risk calculators which include variables such as sex, age, race, ethnicity, and VAT concentration, along with other well-known CVD risk factors in order to comprehensively determine risk of CVD in obese patients. Finally, pre-clinical biomarkers such as pro-inflammatory adipokines should be validated to estimate risk of CVD in obese patients.

Salivary Adipokine and Cytokine Levels as Potential Markers for the Development of Obesity and Metabolic Disorders

Currently, the number of people suffering from obesity is increasing worldwide. In addition, the disease is affecting younger individuals. Therefore, it is essential to search for new diagnostic methods and markers for early assessment of the risk of obesity, metabolic disorders, and other comorbidities. The discovery of the secretory function of adipose tissue and coexistence of low-grade chronic inflammation with obesity set a new direction in this disease diagnosis using the assessment of the concentration of inflammatory markers secreted by adipose tissue. The aim of this review was to determine, based on previous findings, whether saliva can be useful in the diagnosis of obesity and its early metabolic complications and whether it can be an alternative diagnostic material to serum.

Waist-to-Height Ratio Is a Good Predictor of Metabolic Syndrome in Adolescents: A Report From the Thai National Health Examination Survey V, 2014

This study aimed to assess the performance of waist-to-height ratio (WHtR) in the prediction of metabolic syndrome and to determine the appropriate cutoff value in Thai adolescents. Demographic data, blood pressure, fasting blood glucose, and lipid profile were obtained from the Thai National Health Examination Survey V database. The performances of WHtR, waist circumference, body mass index (BMI), and BMI z-score were analyzed by the receiver operating characteristics. Among 2644 adolescents, metabolic syndrome was identified in 4.27%. The areas under the receiver operating characteristic curves of WHtR, waist circumference, BMI, and BMI z-score were comparable (0.924-0.960). Performance of WHtR was more constant across age groups compared with other parameters. Using the cutoff value of WHtR at 0.5 resulted in the sensitivity and specificity of 98.5%/83.4% and 88.9%/86.0% in males and females, respectively. In conclusion, the cutoff value of WHtR at 0.5 provided good sensitivity and specificity for identifying metabolic syndrome in both genders. However, the other clinical risk factors or more definite scores should be considered when further assessment.

Diet and physical activity in Greenland: genetic interactions and associations with obesity and diabetes

The Inuit in Greenland have gone through dramatic lifestyle changes during the last half century. More time is spent being sedentary and imported foods replaces traditional foods like seal and whale. The population has also experienced a rapid growth in obesity and metabolic disturbances and diabetes is today common despite being almost unknown few decades ago. In this paper, we describe and discuss the role of lifestyle changes and genetics for Inuit metabolic health. Novelty: Cardiometabolic disease risk has increased in Greenland. Lifestyle changes and possibly gene-lifestyle interactions play a role.

Prognostic Association of TERC, TERT Gene Polymorphism, and Leukocyte Telomere Length in Acute Heart Failure: A Prospective Study

BACKGROUND

Telomere length and telomerase are associated in development of cardiovascular diseases. Study aims to investigate the associations of TERC and TERT gene polymorphism and leukocyte telomere length (LTL) in the prognosis of acute heart failure (AHF).

METHODS

Total 322 patients with AHF were enrolled and divided into death and survival group according to all-cause mortality within 18 months. Seven single nucleotide polymorphisms (SNPs) of TERC and TERT were selected. Baseline characteristics, genotype distribution and polymorphic allele frequency, and genetic model were initially analyzed. Genotypes and the LTL were determined for further analysis.

RESULTS

Compared to carrying homozygous wild genotype, the risk of death in patients with mutated alleles of four SNPs- rs12696304(G>C), rs10936599(T>C), rs1317082(G>A), and rs10936601(T>C) of TERC were significantly higher. The dominant models of above were independently associated with mortality. In recessive models, rs10936599 and rs1317082 of TERC, rs7726159 of TERT were independently associated with long-term mortality. Further analysis showed, in haplotype consisting with TERC - rs12696304, rs10936599, rs1317082, and rs10936601, mutant alleles CCAC and wild alleles GTGT were significant difference between groups (P<0.05). CCAC is a risk factor and GTGT is a protective factor for AHF patients. Relative LTL decreased over age, but showed no difference between groups and genotypes.

CONCLUSIONS

The SNPs of TERC and TERT are associated with the prognosis of AHF, and are the independent risk factors for predicting 18-month mortality in AHF.