Comparison of regional fat measurements by dual-energy X-ray absorptiometry and conventional anthropometry and their association with markers of diabetes and cardiovascular disease risk

Association between A/G ratio and arterial stiffness among Chinese type 2 diabetics: A cross-sectional study

BACKGROUND

The android-to-gynoid fat ratio (A/G ratio), an emerging indicator of obesity independent of body mass index (BMI), has yet to be conclusively associated with arterial stiffness in type 2 diabetes mellitus (T2DM). This study aimed to construct a nomogram to estimate arterial stiffness risk in diabetics and explore the interaction effect between A/G ratio and traditional obesity indicators on arterial stiffness.

METHODS

1313 diabetics were divided into 2 groups based on arterial stiffness identified by brachial ankle pulse wave velocity (baPWV), and demographic and clinical features were measured. The LASSO and multivariate logistics regression were used to develop the nomogram. Calibration curve, decision curve analysis (DCA) and receiver operating characteristic (ROC) were applied to assess calibration and clinical usefulness. Interaction effect analysis was performed to quantify the interactive relationship of A/G ratio and obesity indicators on arterial stiffness.

RESULTS

6 independent predictors (age, gender, A/G ratio, SBP, LDL-C and HbA1C) were screened to construct a nomogram prediction model. The calibration curve demonstrated satisfactory agreement between predicted and actual probability, and the nomogram exhibited clinical beneficial at the threshold between 8 % and 95 % indicated by DCA. The area under curve (AUC) was 0.918 and 0.833 for training and external set, respectively. Further investigation revealed A/G ratio and BMI acted positively synergistically towards arterial stiffness, and in BMI-based subgroup analysis, elevated A/G ratio was a significant risk factor for arterial stiffness, especially in normal BMI.

CONCLUSIONS

A/G ratio showed a substantial association with arterial stiffness, and the nomogram, incorporating age, gender, A/G ratio, SBP, LDL-C, and HbA1c, exhibited high predictive value. A/G ratio measurement in BMI-normal individuals assisted in identifying cardiovascular diseases early.

Change in neighborhood socioeconomic status and childhood weight status and body composition from birth to adolescence

BACKGROUND

We aim to assess the associations between the change in neighborhood socioeconomic score (SES) between birth and 6 years and childhood weight status and body composition from 6 to 13 years.

METHODS

Data for 3909 children from the Generation R Study, a prospective population-based cohort in the Netherlands were analyzed. The change in neighborhood SES between birth and 6 years was defined as static-high, static-middle, static-low, upward, and downward mobility. Child body mass index (BMI), overweight and obesity (OWOB), fat mass index (FMI) and lean mass index (LMI) were measured at age 6, 10, and 13 years. The associations were explored using generalized estimating equations. The effect modification by child sex was examined.

RESULTS

In total, 19.5% and 18.1% of children were allocated to the upward mobility and downward mobility neighborhood SES group. The associations between the change in neighborhood SES and child weight status and body composition were moderated by child sex (p < 0.05). Compared to girls in the static-high group, girls in the static-low group had relatively higher BMI-SDS (β, 95% confidence interval (CI): 0.24, 0.09-0.40) and higher risk of OWOB (RR, 95% CI: 1.98, 1.35-2.91), together with higher FMI-SDS (β, 95% CI: 0.27, 0.14-0.41) and LMI-SDS (β, 95% CI: 0.18, 0.03-0.33). The associations in boys were not significant.

CONCLUSIONS

An increased BMI and fat mass, and higher risk of OWOB from 6 to 13 years were evident in girls living in a low-SES neighborhood or moving downward from a high- to a low-SES neighborhood. Support for children and families from low-SES neighborhoods is warranted.

Increased visceral fat area to skeletal muscle mass ratio is positively associated with the risk of metabolic dysfunction-associated steatotic liver disease in a Chinese population

BACKGROUND

The diagnosis and comprehension of nonalcoholic fatty liver disease (NAFLD), recently redefined as metabolic dysfunction-associated steatotic liver disease (MASLD) are gaining a better understanding. In this study, we examined the association between visceral fat area and skeletal muscle mass ratio (VSR) and the prevalence of MASLD in a Chinese population.

METHODS

A cross-sectional study was conducted involving 10,916 individuals who underwent bioelectrical impedance analysis, along with anthropometric and biochemical measurements, from January 2022 to June 2023. According to the VSR distribution, sex-specific quartiles of VSR within the study population were defined. Linear trend tests were performed for the categorized VSR variables. Logistic regression models were performed to estimate the odds ratio and 95% confidence intervals between VSR distribution and MASLD prevalence stratified by sex.

RESULTS

The prevalence of MASLD was 37.94% in the overall population (56.34% male), and it gradually increased with higher VSR levels in both genders (P < 0.001). Logistic regression analysis demonstrated a significant association between VSR and MASLD prevalence after adjusting for confounders. The odds ratio (95% confidence interval) for MASLD, comparing the lowest to the highest VSR quartile, was 3.159 (2.671, 3.736) for men and 2.230 (1.764, 2.819) for women (all P < 0.001). Restricted cubic splines also indicated significant non-linear relationships between VSR and MASLD prevalence.

CONCLUSIONS

VSR is positively associated with the prevalence of MASLD in this Chinese population, with a notably higher risk for men as VSR increases compared to women.

Visceral-to-peripheral adiposity ratio: a critical determinant of sex and ethnic differences in cardiovascular risks among Asian Indians and African Creoles in Mauritius

BACKGROUND/AIMS

Coronary heart disease morbidity and mortality are higher in people of South Asian origin than in those of African origin. We investigated whether as young adults without diabetes, people in Mauritius of South Asian descent (Indians) would show a more adverse cardiovascular risk profile that those of predominantly African descent (Creoles), and whether this could be explained by ethnic differences in visceral adiposity or other fat distribution patterns.

METHODS

The study was conducted in 189 young non-physically active adults, with the following measurements conducted after an overnight fast: anthropometry (weight, height, waist circumference), whole-body and regional body composition by dual-energy x-ray absorptiometry, blood pressure, and blood assays for glycemic (glucose and HbA1c) and lipid profile (triglycerides and cholesterols).

RESULTS

The results indicate higher serum triglycerides and lower HDL cholesterol in men than in women, and in Indians than in Creoles (p < 0.001). No significant differences due to sex or ethnicity are observed in body mass index and waist circumference, but indices of visceral adiposity (visceral/android, visceral/subcutaneous) and visceral-to-peripheral adiposity ratio (visceral/gynoid, visceral/limb) were significantly higher in men than in women, and in Indians than in Creoles. The significant effects of sex and ethnicity on blood lipid profile were either completely abolished or reduced to a greater extent after adjusting for the ratio of visceral-to-peripheral adiposity than for visceral adiposity per se.

CONCLUSIONS

In young adults in Mauritius, Indians show a more adverse pattern of body fat distribution and blood lipid risk profile than Creoles. Differences in their fat distribution patterns, however, only partially explain their differential atherogenic lipid risk profile, amid a greater impact of visceral-to-peripheral adiposity ratio than that of visceral adiposity per se on sex and ethnic differences in cardiovascular risks; the former possibly reflecting the ratio of hazardous (visceral) adiposity and protective (peripheral) superficial subcutaneous adiposity.

The effect of hyperlipidemia and body fat distribution on subclinical left ventricular function in obesity: a cardiovascular magnetic resonance study

BACKGROUND

Obesity is often associated with multiple comorbidities. However, whether obese subjects with hyperlipidemia in the absence of other complications have worse cardiac indices than metabolically healthy obese subjects is unclear. Therefore, we aimed to determine the effect of hyperlipidemia on subclinical left ventricular (LV) function in obesity and to evaluate the association of cardiac parameters with body fat distribution.

MATERIALS AND METHODS

Ninety-two adults were recruited and divided into 3 groups: obesity with hyperlipidemia (n = 24, 14 males), obesity without hyperlipidemia (n = 25, 13 males), and c ntrols (n = 43, 25 males). LV strain parameters (peak strain (PS), peak diastolic strain rate (PDSR), peak systolic strain rate) derived from cardiovascular magnetic resonance tissue tracking were measured and compared. Dual-energy X-ray absorptiometer was used to measure body fat distribution. Correlations of hyperlipidemia and body fat distribution with LV strain were assessed by multivariable linear regression.

RESULTS

Obese individuals with preserved LV ejection fraction showed lower global LV longitudinal, circumferential, and radial PS and longitudinal and circumferential PDSR than controls (all P < 0.05). Among obese patients, those with hyperlipidemia had lower longitudinal PS and PDSR and circumferential PDSR than those without hyperlipidemia (- 12.8 ± 2.9% vs. - 14.2 ± 2.7%, 0.8 ± 0.1 s-1 vs. 0.9 ± 0.3 s-1, 1.2 ± 0.2 s-1 vs. 1.4 ± 0.2 s-1; all P < 0.05). Multivariable linear regression demonstrated that hyperlipidemia was independently associated with circumferential PDSR (β = - 0.477, P < 0.05) in obesity after controlling for growth differences, other cardiovascular risk factors, and central fat distribution. In addition, android fat had an independently negative relationship with longitudinal and radial PS (β = - 0.486 and β = - 0.408, respectively; all P < 0.05); and visceral fat was negatively associated with longitudinal PDSR (β = - 0.563, P < 0.05). Differently, gynoid fat was positively correlated with circumferential PS and PDSR and radial PDSR (β = 0.490, β = 0.481, and β = 0.413, respectively; all P < 0.05).

CONCLUSION

Hyperlipidemia is independently associated with subclinical LV diastolic dysfunction in obesity. Central fat distribution (android and visceral fat) has a negative association, while peripheral fat distribution (gynoid fat) has a positive association on subclinical LV function. These results suggest that appropriate management of hyperlipidemia may be beneficial for obese patients, and that the differentiation of fat distribution in different regions may facilitate the precise management of obese patients. Clinical trials registration Effect of lifestyle intervention on metabolism of obese patients based on smart phone software (ChiCTR1900026476).

Distinct subpopulations of human subcutaneous adipose tissue precursor cells revealed by single-cell RNA sequencing

Adipose-derived stem cells (ADSCs) play an important role in the differential capacity for excess energy storage between upper body abdominal (ABD) adipose tissue (AT) and lower body gluteofemoral (GF) AT. We cultured ADSCs from subcutaneous ABD AT and GF AT isolated from eight women with differential body fat distribution and performed single-cell RNA sequencing. Six populations of ADSCs were identified and segregated according to their anatomical origin. The three ADSC subpopulations in GF AT were characterized by strong cholesterol/fatty acid (FA) storage and proliferation signatures. The two ABD subpopulations, differentiated by higher expression of committed preadipocyte marker genes, were set apart by differential expression of extracellular matrix and ribosomal genes. The last population, identified in both depots, was similar to smooth muscle cells and when individually isolated and cultured in vitro they differentiated less than the other subpopulations. This work provides important insight into the use of ADSC as an in vitro model of adipogenesis and suggests that specific subpopulations of GF-ADSCs contribute to the more robust capacity for GF-AT to expand and grow compared with ABD-AT in women.NEW & NOTEWORTHY Identification of distinct subpopulations of adipose-derived stem cells (ADSCs) in upper body abdominal subcutaneous (ABD) and lower body gluteofemoral subcutaneous (GF) adipose tissue depots. In ABD-ADSCs, subpopulations are more committed to adipocyte lineage. GF-ADSC subpopulations are enriched for genes involved in lipids and cholesterol metabolism. Similar depot differences were found in stem cell population identified in freshly isolated stoma vascular fraction. The repertoire of ADSCs subpopulations was different in apple-shaped versus pear-shaped women.

Postprandial glucose variability and clusters of sex hormones, liver enzymes, and cardiometabolic factors in a South African cohort of African ancestry

INTRODUCTION

This study aimed to, first, determine the clusters of sex hormones, liver enzymes, and cardiometabolic factors associated with postprandial glucose (PPG) and, second to evaluate the variation these clusters account for jointly and independently with polygenic risk scores (PRSs) in South Africans of African ancestry men and women.

RESEARCH DESIGN AND METHODS

PPG was calculated as the integrated area under the curve for glucose during the oral glucose tolerance test (OGTT) using the trapezoidal rule in 794 participants from the Middle-aged Soweto Cohort. Principal component analysis was used to cluster sex hormones, liver enzymes, and cardiometabolic factors, stratified by sex. Multivariable linear regression was used to assess the proportion of variance in PPG accounted for by principal components (PCs) and type 2 diabetes (T2D) PRS while adjusting for selected covariates in men and women.

RESULTS

The T2D PRS did not contribute to the PPG variability in both men and women. In men, the PCs' cluster of sex hormones, liver enzymes, and cardiometabolic explained 10.6% of the variance in PPG, with PC1 (peripheral fat), PC2 (liver enzymes and steroid hormones), and PC3 (lipids and peripheral fat) contributing significantly to PPG. In women, PC factors of sex hormones, cardiometabolic factors, and liver enzymes explained a similar amount of the variance in PPG (10.8%), with PC1 (central fat) and PC2 (lipids and liver enzymes) contributing significantly to PPG.

CONCLUSIONS

We demonstrated that inter-individual differences in PPG responses to an OGTT may be differentially explained by body fat distribution, serum lipids, liver enzymes, and steroid hormones in men and women.

The association of a healthy lifestyle index and imaging-based body fat distribution with glycemic status and Type 2 diabetes in the Multi Ethnic Cohort: a cross-sectional analysis

INTRODUCTION

As several behaviors captured by the Lifestyle Risk Factor Index (LSRI) are protective against Type 2 diabetes (T2D) and may affect body fat distribution, we examined its relation with both outcomes.

METHODS

In a subset of the Multiethnic Cohort, participants from five ethnic groups (60-77 years) were assigned LSRI scores (one point each for consuming <1 (women)/<2 (men) alcoholic drinks/day, ≥1.5 physical activity hours/week, not smoking, and adhering to ≥3/7 dietary recommendations). All participants completed an extensive Quantitative Food Frequency Questionnaire to allow estimation of adherence to intake recommendations for fruits, vegetables, refined and whole grains, fish, processed and non-processed meat. Glycemic/T2D status was classified according to self-reports and fasting glucose. We estimated prevalence odds ratios (POR) of LSRI with glycemic/T2D status and DXA- and MRI-based body fat distribution using logistic regression.

RESULTS

Of 1713 participants, 43% had normoglycemia, 30% Pre-T2D, 9% Undiagnosed T2D, and 18% T2D. Overall, 39% scored 0-2, 49% 3, and 12% 4 LSRI points. T2D prevalence was 55% (POR 0.45; 95% confidence intervals 0.27, 0.76) lower for 4 vs. 0-2 LSRI points with weaker associations for abnormal glycemic status. Despite the low adherence to dietary recommendations (22%), this was the only component related to lower T2D prevalence. The inverse LSRI-T2D association was only observed among Latinos and Japanese Americans in ethnic-specific models. Visceral fat measures were higher in T2D patients and attenuated the LSRI-T2D association.

CONCLUSION

These findings support the role of a healthy lifestyle, especially diet, in T2D prevention with differences across ethnicity.

Associations between muscle quality and N-terminal pro-B-type natriuretic peptide (NT-proBNP): The multi-ethnic study of atherosclerosis

INTRODUCTION

N-terminal pro-B-type natriuretic peptide (NT-proBNP) is widely used in clinical settings to identify cardiac stress, diagnose, and manage heart failure (HF). We explored the associations between NT-proBNP and both muscle area and density.

METHODS

A cross-sectional analysis including 1,489 participants from the MESA. Plasma NT-proBNP concentrations and inflammatory biomarkers and health history questionnaires were analyzed. Computed tomography quantified abdominal body composition. Separate multivariable linear regression models were used to assess the associations between both muscle (MA) area and density (MD) and NT-proBNP.

RESULTS

In models adjusted for sociodemographic characteristics, risk factors for cardiovascular disease, anthropometric variables, and subcutaneous and visceral adiposity, NT-proBNP was inversely associated with total abdominal and psoas MAs. Adjustment for inflammatory markers and MD attenuated these associations to the null. Stabilization MA and NT-proBNP were not significantly associated. Analyses per quartiles of MA confirmed lack of a consistent association between stabilization and total abdominal MAs and NT-proBNP. While the third and fourth quartiles of psoas MA were inversely associated with NT-proBNP, adding inflammation biomarkers and MD to the model attenuated the association to the null. Conversely, after full adjustment, NT-proBNP was inversely and significantly associated with total abdominal, stabilization and psoas MDs. For psoas MD, but not the other muscle density variables, the addition of MA to the model attenuated the association to the null. The quartiles of MD were consistently inversely associated with NT-proBNP, where higher MDs showed larger estimates of the association compared to the lowest quartiles, for all muscle groups investigated.

CONCLUSION

Muscle density is inversely associated with NT-proBNP, while muscle area is not after adjustment for inflammation and muscle density.

The relationship between fat distribution and diabetes in US adults by race/ethnicity

Introduction

This study examined the relationship between fat distribution and diabetes by sex-specific racial/ethnic groups.

Methods

A secondary data analysis of National Health and Nutrition Examination Survey 2011-2018 data (n = 11,972) was completed. Key variables examined were visceral adipose tissue area (VATA), subcutaneous fat area (SFA), diabetes prevalence, and race/ethnicity. The association of VATA and SFA and diabetes prevalence was examined separately and simultaneously using multiple logistic regression. Bonferroni corrections were applied to all multiple comparisons between racial/ethnic groups. All analyses were adjusted for demographics and muscle mass.

Results

VATA was positively associated with diabetes in both sexes (p < 0.001) and across all racial/ethnic groups (p < 0.05) except Black females. No statistically significant relationships were observed between SFA and diabetes while accounting for VATA with the exception of White females (p = 0.032). When comparing racial/ethnic groups, the relationship between VATA and diabetes was stronger in White and Hispanic females than in Black females (p < 0.005) while the relationship between SFA and diabetes did not differ between any racial/ethnic groups.

Conclusion

This study found that VATA is associated with diabetes for both sexes across almost all racial/ethnic groups independent of SFA whereas the only significant relationship between SFA and diabetes, independent of VATA, was observed in White females. The findings indicated that visceral fat was more strongly associated with diabetes than subcutaneous. Additionally, there are health disparities in sex-specific racial/ethnic groups thus further study is warranted.

Body composition analysis: A snapshot across the perimenopause

During the perimenopause, estrogen concentrations gradually decrease, and this is associated with changes to women's energy expenditure and intake. These changes result in weight gain and altered body fat distribution, with increased abdominal fat deposition and cardiometabolic risk via insulin resistance. Body composition analysis is a useful clinical tool in outpatient settings, as it is simple, not expensive and provides information on body mass index, skeletal mass, fat mass, fat percentage and basal metabolic rate. This review discusses body composition analysis as part of a health assessment for healthy women during the perimenopause and investigates the associations between body composition and cardiometabolic profile.

Age-related variations in trunk composition and patterns of regional bone and soft tissue changes in adult Caucasian women by DXA

We explored the regional variations in body composition with advancing age in healthy Caucasian females living in the Mediterranean area. The objectives of this study were to establish body composition values for the trunk in healthy women of a Greek origin and to evaluate the effects of aging on the distribution of truncal bone mass, fat mass (FM) and lean mass (LM). Body composition of the trunk and detailed analysis of its anatomical components-the ribs, the thoracic spine, the lumbar spine and the pelvis, and FM and LM ratios--were calculated in 330 women aged 20-85 years, using DXA. Peak bone mineral density (BMD) of the trunk was attained between ages 30 and 33. The overall truncal BMD reduction with age was 20.7% (p < 0.001). Peak %LM of the trunk was achieved at age 20. The overall reduction of %LM with age for the trunk was 9.8% (p < 0.001). Peak %FM of the trunk was attained between ages 68 and 73, and the overall %FM reduction with age was 2.8% (p > 0.05). Multiple comparative analyses showed that the 51-60 years age group was the landmark age for significant changes of truncal bone mass measures across all age groups (p = 0). For truncal LM and FM metrics, multigroup comparative analysis showed the turning point of significant changes in soft tissue was the 41-50 age bracket (p = 0 and p = 0, respectively). In Greek women, truncal %LM exceeded by far %FM across all ages (p = 0). Our results suggest that aging affects body composition of the trunk in ambulatory healthy women of a Greek origin differently, leading to menopausal loss of bone mass, senior adulthood loss of lean mass, and middle-age storage of fat mass. In adult women, these age-related associations between bone and soft tissue metrics on DXA exams carry implications for the attainment of optimal peak values and shifts in body composition overtime, impacting lifelong skeletal health.

Association between body composition and cardiometabolic disease risk: role of dietary fat intake and APOLIPOPROTEIN E genotype on this relationship

Excess body weight is associated with increased mortality and risk of developing CVD. Body fat distribution is now considered a better indicator of disease risk than BMI, with central adiposity associated with dyslipidaemia and insulin resistance. Dietary modification is unquestionably important in the prevention of obesity and CVD, with the type but not the amount of dietary fat emerging as an important determinant of both diseases. Although reducing SFA intake via replacement with unsaturated fatty acids (UFA) is a key public health strategy for CVD prevention, variability in the lipid lowering response has been observed. This narrative review aims to investigate the link between adiposity and CVD risk, and the role of dietary fat composition and APOLIPOPROTEIN (APO)E genotype on this relationship. In the absence of weight loss, replacing dietary SFA with UFA reduces central adiposity and anthropometric measures, and is linked with lower total and LDL-cholesterol concentrations. However, differences in study populations and body composition techniques need to be taken into consideration. To date, only a limited number of studies have determined the role of APOE on body composition and CVD risk, but findings are inconsistent. Both APOE2 and APOE4 alleles have been correlated with adiposity related markers, and an APOE genotype-BMI interaction has been reported on fasting lipids. However, studies are often performed retrospectively leading to small sample sizes within the genotype groups. Further studies are needed to confirm the relationship between APOE genotype, adiposity and circulating CVD risk markers.

Mid-arm muscle circumference and triceps skinfold thickness associated with cardiometabolic disease in Chinese residents: A prospective cohort study

BACKGROUND AND AIMS

The association of cardiometabolic disease (CMD) with body muscle and fat mass remains unclear. Mid-arm muscle circumference (MAMC) and triceps skinfold (TSF) thickness are easily obtained measuring methods for these two body compositions. This study aimed to investigate the association of CMD with MAMC and TSF thickness among Chinese residents.

METHODS

A total of 9440 eligible participants from the China Health and Nutrition Survey were included in the analysis. Associations of CMD prevalence with MAMC and TSF thickness were estimated using logistic regression models. Multivariable COX proportional-hazards regression models were used to estimate the effect of baseline MAMC and TSF thickness on subsequent CMD.

RESULTS

Positive associations of CMD prevalence with MAMC (odds ratio [OR] = 1.169, 95% confidence interval [CI] 1.110-1.232, P < 0.001) and TSF thickness (OR = 1.313, 95%CI 1.240-1.390, P < 0.001) were observed in the cross-sectional analysis. In the longitudinal study, a 1-SD increase in MAMC was associated with a 13.6% increased risk of CMD incidence (hazard ratio [HR] = 1.136, 95%CI 1.073-1.204, P < 0.001), and a 1-SD increase in TSF thickness had a 17.6% increased risk of CMD incidence (HR = 1.176, 95%CI 1.084-1.276, P < 0.001). For the CMD components, both MAMC and TSF thickness contributed to increased incidences of hypertension (HR = 1.163, 95%CI 1.097-1.233, P < 0.001 in MAMC; HR = 1.218, 95%CI 1.110-1.336, P < 0.001 in TSF thickness) and diabetes mellitus (HR = 1.166, 95%CI 1.028-1.323, P = 0.017 in MAMC; HR = 1.352, 95%CI 1.098-1.664, P = 0.004 in TSF thickness).

CONCLUSIONS

Individuals with higher MAMC and TSF thickness had an increased incidence of CMD, mainly hypertension and diabetes mellitus. This study revealed a seemingly counterintuitive association between body muscle mass and metabolic homeostasis. Although the potential mechanisms require further exploration, the impact of body muscle mass on metabolic health cannot be ignored.

Normal-weight central obesity and risk of cardiovascular and microvascular events in adults with prediabetes or diabetes: Chinese and British cohorts

OBJECTIVE

To investigate the relationship between body fat distribution and risk of cardiometabolic and microvascular events among individuals with prediabetes or diabetes with normal body mass index (BMI).

METHODS

A total of 17,232 participants with prediabetes or diabetes from UK Biobank (UKB) with 12-year follow-up and 499 diabetic participants from China with 2-year follow-up with normal BMI were included. Anthropometric measurements of waist circumference (WC), waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR), and body fat composition assessment of trunk-to-leg fat ratio (TLFR) were obtained. Outcomes included incident all-cause and cardiovascular mortality and macrovascular and microvascular diseases.

RESULTS

In British cohort, participants with central obesity defined by WHR had 27%-54% higher risk of incident all-cause mortality (hazard ratio (HR) 1.42, 95% confidence interval (CI): 1.23-1.64), cardiovascular mortality (HR 1.54 [1.15-2.07]), myocardial infarction (HR = 1.43 [1.15, 1.78]), stroke (HR 1.26 [0.90, 1.75]), heart failure (HR = 1.27 [1.00, 1.61]), diabetic nephropathy (HR 1.33 [1.07, 1.65]), and diabetic retinopathy (DR) (HR = 1.48 [1.12, 1.96]) than those without obesity. Central obesity defined by WC and WHtR was associated with 40%-44% and 23%-98% higher risks of developing diabetic events, respectively. In the Chinese cohort, individuals with abdominal obesity, defined by WC (HR 1.44) or WHtR (HR 1.43) but not by WHR, carried more than 40% higher risk of developing DR than those without it. Higher TLFR carried 1.30-2.85 times higher risk of CVD and microvascular diseases among the dysglycemic population.

CONCLUSIONS

Body fat distribution diseases among individuals with prediabetes or diabetes are associated with an increased risk of cardiometabolic and microvascular diseases independent of BMI.

The association of body composition and fat distribution with dysmobility syndrome in community-dwelling older adults: Bushehr Elderly Health (BEH) program

BACKGROUND AND OBJECTIVE

Dysmobility Syndrome (DS) is characterized as an accumulation of clinical risk factors for functional disability, such as osteoporosis, sarcopenia, and obesity. Neurological disorders that affect the motor and sensory systems can also contribute to the condition, resulting in gait and muscle strength disturbances, as well as a history of falls and fractures. The study aimed to determine the association between fat distribution in different body areas and the odds of older adults developing DS, as there is still uncertainty about the accumulation of fat in which area is most closely linked to the condition.

METHODS

This cross-sectional study was conducted according to the data from the second phase of the Bushehr Elderly Health Cohort (BEH). Dysmobility Syndrome was defined based on the co-occurrence of at least three outcomes of its criteria. Body composition was measured using dual-energy X-ray absorptiometry (DXA) and anthropometric studies. For evaluating the relationship, multivariate logistic regression and adjusted univariate linear regression were used.

RESULTS

Of 2,359 who were recruited in the study, 1,277 participants (54.13%) had DS. According to the final logistic regression model in the limb region, FM and FM to FFM ratios were significantly associated with DS [OR (95%CI) = 1.04 (1.02 to 1.05), and 3.42 (1.95 to 5.99), respectively]. Also, In the trunk region, the FM and FM to FFM ratio were significantly related to the odds of DS, although this relationship was weaker than in the limbs region [OR (95%CI) = 1.02 (1.00 to 1.03), and 2.45 (1.36 to 4.39), respectively].

CONCLUSION

Our findings indicate that a higher regional and whole-body amount of fat mass rather than fat-free mass is closely linked to an increased risk of DS, particularly in the elderly population. Notably, higher fat mass in the limbs (especially in the legs) is associated with greater odds of DS, while a higher android-to-gynoid fat mass ratio is associated with lower DS risk. Screening fat mass distribution in older individuals can be a valuable strategy for promptly diagnosing DS, implementing interventions to prevent disabilities, and improving their quality of life.

Anthropometric and DXA-derived measures of body composition in relation to pre-diabetes among adults

INTRODUCTION

Abdominal obesity is the most common risk factor of pre-diabetes and diabetes. Currently, several types of indices are used for the determination of visceral fat-related abdominal obesity. To better understand the effect of the different adiposity indices, we sought to evaluate the association of different adiposity measurements, assessed using dual-energy X-ray absorptiometry (DXA), and pre-diabetes.

RESEARCH DESIGN AND METHODS

This cross-sectional study included 1184 adults between 18 and 65 years who participated in the Kuwait Wellbeing Study. Anthropometry measurements included body mass index (BMI) and waist-to-hip ratio. Total body fat (TBF) mass, android fat mass, gynoid fat, and visceral adipose tissue (VAT) mass were measured using the Lunar iDXA. Pre-diabetes was defined as 5.7≤HbA1c%≤6.4. Adjusted prevalence ratios (aPRs) and 95% CIs were estimated. Area under the curve (AUC) was estimated for each adiposity measurement as predictor of pre-diabetes.

RESULTS

A total of 585 (49.4%) males and 599 (50.6%) females were enrolled in the study. Increased BMI (aPR obese vs normal=1.59, 95% CI: 1.19 to 2.12), waist-to-hip ratio (aPR Q4 vs Q1=1.25, 0.96 to 1.61), TBF (aPR Q4 vs Q1=1.58, 1.20 to 2.07), android fat (aPR Q4 vs Q1=1.67, 1.27 to 2.20), gynoid fat (aPR Q4 vs Q1=1.48, 1.16 to 1.89), android-to-gynoid fat ratio (aPR Q4 vs Q1=1.70, 1.27 to 2.28), and VAT mass (aPR Q4 vs Q1=2.05, 1.49 to 2.82) were associated with elevated pre-diabetes prevalence. Gynoid fat was associated with pre-diabetes among males (aPR Q4 vs Q1=1.71, 1.22 to 2.41), but not among females (aPR Q4 vs Q1=1.27, 0.90 to 1.78). Moreover, in terms of AUC, VAT had the highest estimated AUC of 0.680, followed by android-to-gynoid fat ratio (AUC: 0.647) and android fat (AUC: 0.646).

CONCLUSIONS

Pre-diabetes prevalence increased as adiposity measurements increased, with VAT mass demonstrating the highest AUC for pre-diabetes.

Assessment of correlation between conventional anthropometric and imaging-derived measures of body fat composition: a systematic literature review and meta-analysis of observational studies

BACKGROUND

In studies of the association of adiposity with disease risk, widely used anthropometric measures of adiposity (e.g. body-mass-index [BMI], waist circumference [WC], waist-hip ratio [WHR]) are simple and inexpensive to implement at scale. In contrast, imaging-based techniques (e.g. magnetic resonance imaging [MRI] and dual x-ray absorptiometry [DXA]) are expensive and labour intensive, but can provide more accurate quantification of body fat composition. There is, however, limited evidence about the relationship between conventional and imaging-derived measures of adiposity.

METHODS

We searched Scopus and Web of Science for published reports in English of conventional versus imaging-derived measurements of adiposity. We identified 42 articles (MRI = 22; DXA = 20) that met selection criteria, involving 42,556 (MRI = 15,130; DXA = 27,426) individuals recruited from community or hospital settings. Study-specific correlation coefficients (r) were transformed using Fisher's Z transformation, and meta-analysed to yield weighted average correlations, both overall and by ancestry, sex and age, where feasible. Publication bias was investigated using funnel plots and Egger's test.

RESULTS

Overall, 98% of participants were 18 + years old, 85% male and 95% White. BMI and WC were most strongly correlated with imaging-derived total abdominal (MRI-derived: r = 0.88-; DXA-derived: 0.50-0.86) and subcutaneous abdominal fat (MRI-derived: 0.83-0.85), but were less strongly correlated with visceral abdominal fat (MRI-derived: 0.76-0.79; DXA-derived: 0.80) and with DXA-derived %body fat (0.76). WHR was, at best, strongly correlated with imaging-derived total abdominal (MRI-derived: 0.60; DXA-derived: 0.13), and visceral abdominal fat (MRI-derived: 0.67; DXA-derived: 0.65), and moderately with subcutaneous abdominal (MRI-derived: 0.54), and with DXA-derived %body fat (0.58). All conventional adiposity measures were at best moderately correlated with hepatic fat (MRI-derived: 0.36-0.43). In general, correlations were stronger in women than in men, in Whites than in non-Whites, and in those aged 18 + years.

CONCLUSIONS

In this meta-analysis, BMI and WC, but not WHR, were very strongly correlated with imaging-derived total and subcutaneous abdominal fat. By comparison, all three measures were moderately or strongly correlated with imaging-based visceral abdominal fat, with WC showing the greatest correlation. No anthropometric measure was substantially correlated with hepatic fat. Further larger studies are needed to compare these measures within the same study population, and to assess their relevance for disease risks in diverse populations.

Gender-specific associations between abdominal adipose mass and bone mineral density in the middle-aged US population

OBJECTIVES

The relationship between abdominal adipose tissue and osteoporosis is poorly understood. The purpose of this study was to examine the associations of abdominal adipose tissue with bone mineral density (BMD) among a nationally representative sample of US middle-aged adults.

MATERIAL AND METHODS

This study included 1498 participants from the National Health and Nutrition Examination Survey 2013-2014 and 2017-2018. Dual-energy x-ray absorptiometry was used to measure BMD at the lumbar spine and femoral neck, as well as to assess abdominal adipose mass by categorizing total adipose tissue (TAT) into visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT). Linear regression was used to assess the relationship between abdominal adipose tissue and BMD, and logistic regression and generalized additive model were used to assess the associations of abdominal adipose tissue with the development of low BMD.

RESULTS

In our study, men accounted for 51.3%, and the mean age and body mass index for men and women were 49.3 and 49.6 years, and 23.9 and 28.3 kg/m2, respectively. In the univariate model, we found that abdominal adipose mass was positively associated with BMD at femoral neck and spine in both genders. In the multivariate model, among men, a negative correlation was observed between TAT and SAT and BMD at the femoral neck. Additionally, higher masses of TAT, SAT, and VAT were found to significantly increase the risk of low BMD at both the femoral neck and lumbar spine. In contrast, there was no significant association between abdominal adipose mass and BMD in middle-aged women, regardless of menopausal status.

CONCLUSIONS

Our finding suggested that abdominal adipose tissue, regardless of its location (SAT or VAT), may have a negative impact on BMD in middle-aged men independently of body weight, but this relationship was not observed in women. Further research is needed to confirm these findings and investigate potential mechanisms underlying these associations.

MLX plays a key role in lipid and glucose metabolism in humans: Evidence from in vitro and in vivo studies

BACKGROUND AND AIM

Enhanced hepatic de novo lipogenesis (DNL) has been proposed as an underlying mechanism for the development of NAFLD and insulin resistance. Max-like protein factor X (MLX) acts as a heterodimer binding partner for glucose sensing transcription factors and inhibition of MLX or downstream targets has been shown to alleviate intrahepatic triglyceride (IHTG) accumulation in mice. However, its effect on insulin sensitivity remains unclear. As human data is lacking, the aim of the present work was to investigate the role of MLX in regulating lipid and glucose metabolism in primary human hepatocytes (PHH) and in healthy participants with and without MLX polymorphisms.

METHODS

PHH were transfected with non-targeting or MLX siRNA to assess the effect of MLX knockdown on lipid and glucose metabolism, insulin signalling and the hepatocellular transcriptome. A targeted association analysis on imputed genotype data for MLX on healthy individuals was undertaken to assess associations between specific MLX SNPs (rs665268, rs632758 and rs1474040), plasma biochemistry, IHTG content, DNL and gluconeogenesis.

RESULTS

MLX knockdown in PHH altered lipid metabolism (decreased DNL (p < 0.05), increased fatty acid oxidation and ketogenesis (p < 0.05), and reduced lipid accumulation (p < 0.001)). Additionally, MLX knockdown increased glycolysis, lactate secretion and glucose production (p < 0.001) and insulin-stimulated pAKT levels (p < 0.01) as assessed by transcriptomic, steady-state and dynamic measurements. Consistent with the in vitro data, individuals with the rs1474040-A and rs632758-C variants had lower fasting plasma insulin (p < 0.05 and p < 0.01, respectively) and TG (p < 0.05 and p < 0.01, respectively). Although there was no difference in IHTG or gluconeogenesis, individuals with rs632758 SNP had notably lower hepatic DNL (p < 0.01).

CONCLUSION

We have demonstrated using human in vitro and in vivo models that MLX inhibition favored lipid catabolism over anabolism and increased glucose production, despite increased glycolysis and phosphorylation of Akt, suggesting a metabolic mechanism that involves futile cycling.

Association between android fat mass, gynoid fat mass and cardiovascular and all-cause mortality in adults: NHANES 2003-2007

Objectives

Evidence of the relationship between android fat mass and gynoid fat mass with the mortality prediction is still limited. Current study analyzed the NHANES database to investigate the relationship between android fat mass, gynoid fat mass and CVD, with all-cause mortality.

Method

The study subjects were NHANES participants over 20 years old, two indicators of regional body composition, android fat and gynoid fat were measured by Dual Energy x-ray Absorptiometry (DEXA). The other various covariates data obtained from the NHANES questionnaire and laboratory measurements, including age, gender, education, race/ethnicity, uric acid, total serum cholesterol, albumin, Vitamin C, folate, alcohol drinking, smoking status, history of diabetes, and hypertension. Mortality status was ascertained from a linked mortality file prepared by the National Center for Health Statistics. The study population was divided quartiles based on the distribution of android fat mass and gynoid fat mass. The relationship between these two indicators with cardiovascular and all-cause mortality was investigated by using Cox regression. The covariates age, gender, smoking status, drinking status, history of diabetes, and history of hypertension were stratified.

Results

In the fully adjusted model, Q3 had the lowest HR in android fat mass and gynoid fat mass. When examining the relationship between android fat mass and CVD mortality, current smokers and drinkers had the lowest CVD risk in Q2 [smoking: 0.21 (0.08, 0.52), drinking: 0.14 (0.04, 0.50)]. In diabetic patients, compared with Q1, other groups with increased android fat mass can significantly reduce the risk of CVD [Q4: 0.17 (0.04, 0.75), Q3: 0.18 (0.03, 1.09), Q2: 0.27 (0.09, 0.83)]. In ≥60 years old and female, the greater the gynoid fat mass, the smaller the HR of all-cause mortality [Q4 for ≥60 years old: 0.57 (0.33, 0.96), Q4 for female: 0.37 (0.23, 0.58)]. People <60 years old had a lower risk of all-cause mortality with gynoid fat mass in Q3 than those ≥60 years old [<60 years: 0.50 (0.27, 0.91), ≥60 years: 0.65 (0.45, 0.95)]. Among subjects without hypertension, the group with the largest android fat mass had the lowest risk of CVD mortality, and the group with the largest gynoid fat mass had the lowest risk of all-cause mortality [Android fat mass: 0.36 (0.16, 0.81), gynoid fat mass: 0.57 (0.39, 0.85)].

Conclusion

Moderate android fat mass and gynoid fat mass (Q3) had the most protective effect. Smokers and drinkers need to control their body fat. Being too thin is harmful to people with diabetes. Increased gynoid fat mass is a protective factor for all-cause mortality in older adults and females. Young people's gynoid fat mass is more protective in the moderate range than older people's. If no high blood pressure exists, people with more android and gynoid fat mass have a lower risk of CVD or all-cause mortality.

Adiposity impacts cognitive function in Asian populations: an epidemiological and Mendelian Randomization study

Background

Obesity and related metabolic disturbances including diabetes, hypertension and hyperlipidemia predict future cognitive decline. Asia has a high prevalence of both obesity and metabolic disease, potentially amplifying the future burden of dementia in the region. We aimed to investigate the impact of adiposity and metabolic risk on cognitive function in Asian populations, using an epidemiological analysis and a two-sample Mendelian Randomization (MR) study.

Methods

The Health for Life in Singapore (HELIOS) Study is a population-based cohort of South-East-Asian men and women in Singapore, aged 30-84 years. We analyzed 8769 participants with metabolic and cognitive data collected between 2018 and 2021. Whole-body fat mass was quantified with Dual X-Ray Absorptiometry (DEXA). Cognition was assessed using a computerized cognitive battery. An index of general cognition ' g ' was derived through factor analysis. We tested the relationship of fat mass indices and metabolic measures with ' g ' using regression approaches. We then performed inverse-variance-weighted MR of adiposity and metabolic risk factors on ' g ', using summary statistics for genome-wide association studies of BMI, visceral adipose tissue (VAT), waist-hip-ratio (WHR), blood pressure, HDL cholesterol, triglycerides, fasting glucose, HbA1c, and general cognition.

Findings

Participants were 58.9% female, and aged 51.4 (11.3) years. In univariate analysis, all 29 adiposity and metabolic measures assessed were associated with ' g ' at P < 0.05. In multivariable analyses, reduced ' g ' was consistently associated with increased visceral fat mass index and lower HDL cholesterol (P < 0.001), but not with blood pressure, triglycerides, or glycemic indices. The reduction in ' g ' associated with 1SD higher visceral fat, or 1SD lower HDL cholesterol, was equivalent to a 0.7 and 0.9-year increase in chronological age respectively (P < 0.001). Inverse variance MR analyses showed that reduced ' g ' is associated with genetically determined elevation of VAT, BMI and WHR (all P < 0.001). In contrast, MR did not support a causal role for blood pressure, lipid, or glycemic indices on cognition.

Interpretation

We show an independent relationship between adiposity and cognition in a multi-ethnic Asian population. MR analyses suggest that both visceral adiposity and raised BMI are likely to be causally linked to cognition. Our findings have important implications for preservation of cognitive health, including further motivation for action to reverse the rising burden of obesity in the Asia-Pacific region.

Funding

The Nanyang Technological University-the Lee Kong Chian School of Medicine, National Healthcare Group, National Medical Research Council, Ministry of Education, Singapore.

The Relationship of Body Fat Ratio to Anthropometric and Metabolic Parameters in Normal Weight and Overweight Women; The Concept of Normal Weight Obesity

Aim: We aimed to underline the importance of “normal weight obesity concept”, prevent the overlooking of Normal Weight Obesity patients, administrate their treatments and explain them the risks regarding their future lives along with making emphasis on the necessity of change in polyclinical practices about the subject. Methods: We selected 200 female patients that were either normal or overweighted for this study. Patients have been divided into 4 groups with respect to their body mass index and body fat percent values. Differences of bioelectrical impedance analysis measurements between the groups, relation of the anthropometric and metabolic parameters and those parameters’ inner correlations have been inspected. Results: Serum levels of fasting plasma glucose, insulin, HOMA-IR, total cholesterol, LDL, triglyceride and TSH were higher in “Normal Weight Obesity” subjects than “Normal Weight Lean” subjects. The mean LDL levels were found to be higher in the Normal Weight Obesity group compared to the other groups and it was found to be statistically significant. Body fat percent was positively correlated to insulin, HOMA-IR, visceral fat rating, waist – hip circumferences, waist to height – hip to height ratios. Conclusion: The importance of measurement of body fat percent and not to overlook the Normal Weight Obesity patients should be emphasized once more. Therefore, in the primary care, during public screening and polyclinical assessment states, patients should be checked for obesity with not only measuring their weights and heights, but also detection of their detailed body composition. Keywords: obesity, body fat distribution, waist to height ratio

The Correlation of Apolipoprotein B with Alterations in Specific Fat Depots Content in Adults

Body mass index (BMI) and blood biomarkers are not enough to predict cardiovascular disease risk. Apolipoprotein B was identified to be associated with cardiovascular disease (CVD) progression. The Dual-energy X-ray Absorption (DXA) results could be considered as a predictor for cardiovascular disease in a more refined way based on fat distribution. The prediction of CVD risk by simple indicators still cannot meet clinical needs. The association of ApoB with specific fat depot features remains to be explored to better co-predict cardiovascular disease risk. An amount of 5997 adults from National Health and Nutrition Examination Survey (NHANES) were enrolled. Their demographic information, baseline clinical condition, blood examination, and DXA physical examination data were collected. Multivariate regression was used to assess the correlation between ApoB and site-specific fat characteristics through different adjusted models. Smooth curve fittings and threshold analysis were used to discover the turning points with 95% confidence intervals. ApoB is positively correlated with arms percent fat, legs percent fat, trunk percent fat, android percent fat, gynoid percent fat, arm circumference and waist circumference after adjustment with covariates for age, gender, race, hypertension, diabetes, hyperlipidemia, coronary heart disease, smoking status and vigorous work activity. The smooth curve fitting and threshold analysis also showed that depot-specific fat had lower turning points of ApoB in both males and females within the normal reference range of ApoB. Meanwhile, females have a lower increase in ApoB per 1% total percent fat and android percent fat than males before the turning points, while females have a higher growth of ApoB per 1% gynoid percent fat than males. The combined specific fat-depot DXA and ApoB analysis could indicate the risk of CVD in advance of lipid biomarkers or DXA alone.

A cross-sectional study of adiposity by DXA and the relationship with endothelial function and low-grade inflammation

INTRODUCTION

To evaluate body composition, especially visceral adipose tissue (VAT), by dual-energy x-ray absorptiometry (DXA) and its relation to endothelial function investigated by venous occlusion plethysmography (VOP) and ultrasensitive C-reactive protein (hsCRP).

METHODOLOGY

This is a cross sectional study in adults of both sexes divided into group 1 (BMI, 20-24.9, n=30), group 2 (BMI, 25-29.9, n=22), group 3 (BMI, 30-34.9, n=27) and group 4 (BMI, 35-39.9, n=22). VAT was analyzed, among other parameters of adiposity, by DXA Lunar iDXA, and co-related to endothelial function, anthropometric evaluation, cardiometabolic variables and hsCRP. For statistical analysis, tests of comparison between groups and correlation were performed using the software SPSS version 25.

RESULTS

Inverse correlation of TFT (total fat mass), % RFM (regional fat mass), FMI (fat mass index) and VAT were identified with increment of arterial blood flow in VOP, except the decrease of the latter, with increase of BMI, adiposity indexes, especially VAT, between groups. hsCRP values showed a direct correlation with progression of adiposity and VAT, between groups.

CONCLUSIONS

VAT progression, by DXA analysis, was associated with a decline in endothelial function and increase of inflammation, demonstrating potential use in early identification of individuals with cardiovascular risk (CVR).

The association of fasting plasma thiol fractions with body fat compartments, biomarker profile, and adipose tissue gene expression

People with high plasma total cysteine (tCys) have higher fat mass and higher concentrations of the atherogenic apolipoprotein B (apoB). The disulfide form, cystine, enhanced human adipogenesis and correlated with total fat mass in a Middle-Eastern cohort. In 35 European adults with overweight (88.6% women) and with dual-X-ray absorptiometry measurements of regional fat, we investigated how cystine compared to other free disulfides in their association with total regional adiposity, plasma lipid and glucose biomarkers, and adipose tissue lipid enzyme mRNA (n = 19). Most total plasma homocysteine (tHcy) (78%) was protein-bound; 63% of total glutathione (tGSH) was reduced. tCys was 49% protein-bound, 30% mixed-disulfide, 15% cystine, and 6% reduced. Controlling for age and lean mass, cystine and total free cysteine were the fractions most strongly associated with android and total fat: 1% higher cystine predicted 1.97% higher android fat mass (95% CI 0.64, 3.31) and 1.25% (0.65, 2.98) higher total fat mass (both p = 0.005). A positive association between tCys and apoB (β: 0.64%; 95% CI 0.17, 1.12%, p = 0.009) was apparently driven by free cysteine and cystine; cystine was also inversely associated with the HDL-associated apolipoprotein A1 (β: -0.57%; 95% CI -0.96, -0.17%, p = 0.007). No independent positive associations with adiposity were noted for tGSH or tHcy fractions. Plasma cystine correlated with CPT1a mRNA (Spearman's r = 0.68, p = 0.001). In conclusion, plasma cystine-but not homocysteine or glutathione disulfides-is associated with android adiposity and an atherogenic plasma apolipoprotein profile. The role of cystine in human adiposity and cardiometabolic risk deserves investigation. ClinicalTrials.gov identifiers: NCT02647970 and NCT03629392.

Relationship Between Regional Adiposity Distribution and Incident Heart Failure in General Populations without Cardiovascular Disease

BACKGROUND

Obesity is associated with a high risk of heart failure. However, the contribution of regional fat distribution evaluated using bioimpedance analysis toward heart failure risk in the general population without cardiovascular disease has rarely been studied.

METHODS

This study included 483,316 participants without heart failure and cardiovascular disease from the UK Biobank study. The regional fat mass was determined by bioimpedance analysis and calculated by dividing the square of height in meters (kg/m²). This study evaluated the association of regional fat mass (arm fat index [AFI], trunk fat index [TFI], and leg fat index [LFI]) with the risk of incident heart failure and whether regional fat mass adds a further prognostic value for heart failure besides body mass index (BMI) in a large prospective cohort study.

RESULTS

During the median 12.1 years, 3134 incident heart failure cases occurred. After adjustment for BMI and other confounding factors, each 1-standard deviation increase in LFI was associated with a 21% lower heart failure risk even after adjusting for BMI and other confounding factors (hazard ratio [HR] 0.79; 95% confidence interval [CI], 0.73-0.85). However, we did not observe heart failure-associated risks with AFI and TFI (HR 1.04; 95% CI, 0.99-1.09; HR 0.97, 95% CI, 0.91-1.04, respectively). Subgroup analysis demonstrated that the protective role of LFI was more prominent in the elderly and female participants (P < .01).

CONCLUSION

Regional fat measurement other than BMI can improve heart failure risk stratification; leg fat plays a protective role, yet arm and trunk fat do not, in the general population without cardiovascular disease.

Large scale phenotype imputation and in vivo functional validation implicate ADAMTS14 as an adiposity gene

Obesity remains an unmet global health burden. Detrimental anatomical distribution of body fat is a major driver of obesity-mediated mortality risk and is demonstrably heritable. However, our understanding of the full genetic contribution to human adiposity is incomplete, as few studies measure adiposity directly. To address this, we impute whole-body imaging adiposity phenotypes in UK Biobank from the 4,366 directly measured participants onto the rest of the cohort, greatly increasing our discovery power. Using these imputed phenotypes in 392,535 participants yielded hundreds of genome-wide significant associations, six of which replicate in independent cohorts. The leading causal gene candidate, ADAMTS14, is further investigated in a mouse knockout model. Concordant with the human association data, the Adamts14-/- mice exhibit reduced adiposity and weight-gain under obesogenic conditions, alongside an improved metabolic rate and health. Thus, we show that phenotypic imputation at scale offers deeper biological insights into the genetics of human adiposity that could lead to therapeutic targets.

Systematic metabolomic studies identified adult adiposity biomarkers with acetylglycine associated with fat loss in vivo

Obesity is associated with various adverse health outcomes. Body fat (BF) distribution is recognized as an important factor of negative health consequences of obesity. Although metabolomics studies, mainly focused on body mass index (BMI) and waist circumference, have explored the biological mechanisms involved in the development of obesity, these proxy composite measures are not accurate and cannot reflect BF distribution, and thus may hinder accurate assessment of metabolic alterations and differential risk of metabolic disorders among individuals presenting adiposity differently throughout the body. Thus, the exact relations between metabolites and BF remain to be elucidated. Here, we aim to examine the associations of metabolites and metabolic pathways with BF traits which reflect BF distribution. We performed systematic untargeted serum metabolite profiling and dual-energy X-ray absorptiometry (DXA) whole body fat scan for 517 Chinese women. We jointly analyzed DXA-derived four BF phenotypes to detect cross-phenotype metabolite associations and to prioritize important metabolomic factors. Topology-based pathway analysis was used to identify important BF-related biological processes. Finally, we explored the relationships of the identified BF-related candidate metabolites with BF traits in different sex and ethnicity through two independent cohorts. Acetylglycine, the top distinguished finding, was validated for its obesity resistance effect through in vivo studies of various diet-induced obese (DIO) mice. Eighteen metabolites and fourteen pathways were discovered to be associated with BF phenotypes. Six of the metabolites were validated in varying sex and ethnicity. The obesity-resistant effects of acetylglycine were observed to be highly robust and generalizable in both human and DIO mice. These findings demonstrate the importance of metabolites associated with BF distribution patterns and several biological pathways that may contribute to obesity and obesity-related disease etiology, prevention, and intervention. Acetylglycine is highlighted as a potential therapeutic candidate for preventing excessive adiposity in future studies.

Adiposity in the older population and the risk of dementia: The Rotterdam Study

INTRODUCTION

We determined associations of total and regional adiposity with incident dementia among older adults.

METHODS

Within the population-based Rotterdam Study, adiposity was measured as total, android, and gynoid fat mass using dual-energy X-ray absorptiometry in 3408 men and 4563 women, every 3 to 6 years between 2002 and 2016. Incident dementia was recorded until 2020.

RESULTS

Higher adiposity measures were associated with a decreased risk of dementia in both sexes. After excluding the first 5 years of follow-up, only the association of gynoid fat among women remained significant (hazard ratio 0.85 [95% confidence interval 0.75-0.97] per standard deviation increase). No major differences in trajectories of adiposity measures were observed between dementia cases and dementia-free controls.

DISCUSSION

Higher total and regional fat mass related to a decreased risk of dementia. These results may be explained by reverse causality, although a protective effect of adiposity cannot be excluded.

HIGHLIGHTS

Total and regional adiposity were assessed using dual-energy X-ray absorptiometry scans in 7971 older adults. All adiposity measures were associated with a decreased risk of dementia. The results suggest a beneficial effect of gynoid fat on the risk of dementia in women. Reverse causation and competing risk may explain these inverse associations.

Gut microbiota accelerates obesity in peri-/post-menopausal women via Bacteroides fragilis and acetic acid

OBJECTIVE

Many animal experiments and epidemiological studies have shown that the gut microbiota (GM) plays an important role in the development of obesity, but the specific biological mechanism involved in the pathogenesis of disease remain unknown. We aimed to examine the relationships and functional mechanisms of GM on obesity in peri- and post-menopausal women.

METHODS

We recruited 499 Chinese peri- and post-menopausal women and performed comprehensive analyses of the gut microbiome, targeted metabolomics for short-chain fatty acids in serum, and host whole-genome sequencing by various association analysis methods.

RESULTS

Through constrained linear regression analysis, we found that an elevated abundance of Bacteroides fragilis (B. fragilis) was associated with obesity. We also found that serum levels of acetic acid were negatively associated with obesity, and that B. fragilis was negatively associated with serum acetic acid levels by partial Spearman correlation analysis. Mendelian randomization analysis indicated that B. fragilis increases the risk of obesity and may causally down-regulate acetic acid levels.

CONCLUSIONS

We found the gut with B. fragilis may accelerate obesity, in part, by suppressing acetic acid levels. Therefore, B. fragilis and acetic acid may represent important therapeutic targets for obesity intervention in peri- and post-menopausal women.

Measurement of subcutaneous fat tissue: reliability and comparison of caliper and ultrasound via systematic body mapping

Caliper and ultrasound (US) are used to measure subcutaneous fat tissue depth (SFT) and then to calculate total body fat. There is no evidence-based recommendation as to whether caliper or US are equally accurate. The aim of this paper was therefore to compare reliability of both methods. In this methodical study, 54 participants (BMI: 24.8 ± 3.5 kg/m²; Age: 43.2 ± 21.7 years) were included. Using systematic body mapping, the SFT of 56 areas was measured. We also analyzed 4 body sites via MRI. A comparison between caliper and US detected clear differences in mean SFT of all areas (0.83 ± 0.33 cm vs. 1.14 ± 0.54 cm; p < 0.001) showing moderate reliability (ICC 0.669, 95%CI: 0.625–0.712). US and MRI revealed in the abdominal area a SFT twice as thick as caliper (2.43 ± 1.36 cm vs. 2.26 ± 1.32 cm vs. 1.15 ± 0.66 cm; respectively). Caliper and US revealed excellent intrarater (ICC caliper: 0.944, 95%CI: 0.926–0.963; US: 0.934, 95%CI: 0.924–0.944) and good interrater reliability (ICC caliper: 0.794, 95%CI: 0.754–0.835; US: 0.825, 95%CI: 0.794–0.857). Despite the high reliability in measuring SFT that caliper and US show, our comparison of the two methods yielded clear differences in SFT, particularly in the abdominal area. In accuracy terms, US is preferable for most mapping areas.

Urinary polycyclic aromatic hydrocarbon excretion and regional body fat distribution: evidence from the U.S. National Health and Nutrition Examination Survey 2001-2016

BACKGROUND

Polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants that may contribute to the etiology of obesity. However, it is unclear whether PAHs from environmental sources are associated with regional body fat distribution, and whether the association varies across racial/ethnic groups who may have differential PAH exposure patterns.

OBJECTIVES

To examine correlations between PAHs and body fat distribution, and potential racial/ethnic differences among U.S. adults.

METHODS

Ten PAHs were measured in spot urine samples from 2691 non-smoking adults (age ≥ 20 years) in the NHANES 2001-2016. Dual-energy X-ray absorptiometry was used to measure fat mass percent (FM%). Partial Pearson correlation coefficients (r) with multivariable adjustment were used to assess PAH-FM% associations.

RESULTS

In the total population, 1-naphthalene, 3-fluorene, and 1-pyrene were inversely correlated with total FM% or trunk FM% (adjusted r ranged: - 0.06 to - 0.08), while 2-naphthalene, 9-fluorene, and 4-phenanthrene were positively correlated with the FM% measurements (r: 0.07-0.11). PAH levels are highest among non-Hispanic Blacks, followed by Hispanics and Whites and some of the correlations were different by these races/ethnicities. Among non-Hispanic Whites, no PAH was correlated with FM%. In contrast, 9-fluorene was positively correlated with total FM% (r = 0.20) and trunk FM% (r = 0.22) among Blacks, and 4-phenanthrene was positively correlated with total FM% (r = 0.23) and trunk FM% (r = 0.24) among Hispanics (P-interaction: 0.010-0.025).

DISCUSSION

In this US adult population, certain PAHs are significantly associated with higher body fat contents among non-Hispanic Blacks and Hispanics but not non-Hispanic Whites, suggesting that minority groups might be particularly susceptible to PAH's obesogenic effects or the effects of other factors that determine the PAH exposure levels. Alternatively, differences in body composition may contribute to differential PAH metabolism in minority groups. Future studies are warranted to explore the racial/ethnic disparity in PAH exposures, drivers of these exposure differences, and mechanisms through which PAHs may influence body composition by races/ethnicities.

DXA-Derived vs Standard Anthropometric Measures for Predicting Cardiometabolic Risk in Middle-Aged Australian Men and Women

It is not clear if dual-energy X-ray absorptiometry (DXA) adiposity measures are superior to standard anthropometric measures for predicting cardiometabolic (CM) risk factors in a middle-aged general population. In the Busselton Healthy Ageing Study, we assessed a range of standard anthropometric and DXA-derived adiposity measures to predict metabolic syndrome (MetS) and CM risk factors in 4831 "baby boomers" aged 45-69 yr. Anthropometric and whole body DXA (GE Lunar Prodigy) measures were collected. Cross-sectional relationships of overall adiposity (BMI; DXA fat mass index, body fat %), central adiposity (waist circumference (WC); DXA trunk fat, android fat, abdominal visceral adipose tissue (VAT)) and ratio index (waist-to-hip ratio; DXA trunk/legs fat, android/gynoid ratio, VAT/total fat) with MetS and its components (as both continuous and binary outcomes) were evaluated using linear and logistic regression adjusting for age and lifestyle factors. Youden's Index was used to determine the optimal cut-points for predicting MetS. In linear regression analyses, central adiposity measures showed stronger associations with MetS score and CM risk factors than overall adiposity measures and fat ratio index, and DXA-VAT provided stronger associations than WC. Logistic regression models showed similar findings. For MetS diagnosis present in 35.9% of males and 24.4% of females, the highest odds ratio (95% CI) per SD change was observed for DXA-VAT (males: 5.02 [4.28, 5.88]; females: 3.91 [3.40, 4.49]), which remained significant (all p < 0.001) after further adjustment for BMI (males: 3.27 [2.65, 4.02]; females: 3.37 [2.79, 4.06]) or WC (males: 2.46 [1.95, 3.10]; females: 2.75 [2.21, 3.43]). The optimal DXA-VAT mass cut-point for predicting MetS was 1608 grams in males and 893 grams in females. DXA-VAT was superior to standard anthropometric and other DXA-derived adiposity measures for prediction of cardiometabolic risk factors, and has clinical utility for identifying middle-aged individuals at increased risk of MetS.

The role of the androgen receptor in the pathogenesis of obesity and its utility as a target for obesity treatments

Obesity is associated with hypothalamic-pituitary-testicular axis dysregulation in males. Here, we summarize recent evidence derived from clinical trials and studies in preclinical animal models regarding the role of androgen receptor (AR) signaling in the pathophysiology of males with obesity. We also discuss therapeutic strategies targeting the AR for the treatment of obesity and their limitations and provide insight into the future research necessary to advance this field.

Increased Consumption of Unsaturated Fatty Acids Improves Body Composition in a Hypercholesterolemic Chinese Population

While an increase in fat intake and the resulting excess calorie intake are implicated in weight gain, different fat types exert variable effects on body composition, with unsaturated fats showing favorable effects on body composition in Western population. Whether and to what extent these associations apply to Asian population have not been established. We investigated the effects of two separate Asian-based oil blends, rich in unsaturated fats, made from refined rice bran, sesame, and flaxseed oils, in comparison with refined olive oil, on body composition using dual-energy X-ray absorptiometry (DXA), from an 8-week, parallel design, randomized trial in 66 men (58.7 ± 5.71 years old, 23.0 ± 2.38 kg/m²) and 69 postmenopausal women (59.1 ± 5.34 years old, 21.7 ± 2.52 kg/m²), with borderline hypercholesterolemia. Despite increases in mean daily intakes of total energy (approximately +400 kcal/day, female, and approximately +240 kcal/day, male), as well as increases in percentage of calories from fats and proteins and decreases in percentage of calories from carbohydrates during the dietary intervention period, there were no significant changes in total body fat mass in both genders and also in all treatment groups. While total body weight increased slightly (0.36 ± 0.12 kg, p = 0.005) in women during intervention, this was mainly due to gain in lean mass (0.38 ± 0.081 kg, p < 0.0001). Correspondingly, there were reductions in total body fat (%), android fat (%), and gynoid fat (%) in women. No significant differences between the 3 intervention oil types were found in any of the measured parameters in either gender. Increasing relative intakes of unsaturated fats may prevent fat mass gain and circumvent muscle mass loss associated with menopause in older Asian women. Long-term studies are needed to confirm findings. This study had been registered on clinicaltrials.gov (Identifier No.: NCT03964857, https://www.clinicaltrials.gov/ct2/show/NCT03964857).

Obesity history, physical exam, laboratory, body composition, and energy expenditure: An Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) 2022

Background

This Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) on History, Physical Exam, Body Composition and Energy Expenditure is intended to provide clinicians an overview of the clinical and diagnostic evaluation of patients with pre-obesity/obesity.

Methods

The scientific information for this CPS is based upon published scientific citations, clinical perspectives of OMA authors, and peer review by the Obesity Medicine Association leadership.

Results

This CPS outlines important components of medical, dietary, and physical activity history as well as physical exams, with a focus on specific aspects unique to managing patients with pre-obesity or obesity. Patients with pre-obesity/obesity benefit from the same preventive care and general laboratory testing as those without an increase in body fat. In addition, patients with pre-obesity/obesity may benefit from adiposity-specific diagnostic testing - both generally and individually - according to patient presentation and clinical judgment. Body composition testing, such as dual energy x-ray absorptiometry, bioelectrical impedance, and other measures, each have their own advantages and disadvantages. Some patients in clinical research, and perhaps even clinical practice, may benefit from an assessment of energy expenditure. This can be achieved by several methods including direct calorimetry, indirect calorimetry, doubly labeled water, or estimated by equations. Finally, a unifying theme regarding the etiology of pre-obesity/obesity and effectiveness of treatments of obesity centers on the role of biologic and behavior efficiencies and inefficiencies, with efficiencies more often associated with increases in fat mass and inefficiencies more often associated with decreases in fat mass.

Conclusion

The Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) on History, Physical Exam, Body Composition and Energy Expenditure is one of a series of OMA CPSs designed to assist clinicians in the care of patients with the disease of pre-obesity/obesity.

The role of FSH in body composition in hematopoietic cell transplant recipients

BACKGROUND

Childhood cancer survivors who received a hematopoietic cell transplantation (HCT) are at increased risk for follicle-stimulating hormone (FSH) abnormalities, which may have a significant negative impact on bone health and body composition. This study's purpose was to examine FSH and body composition in HCT recipients, non-HCT recipients and healthy controls.

METHODS

The study included HCT recipients (n = 24), non-HCT recipients (n = 309), and a control group of healthy siblings (n = 211) all aged 9-18 years. A fasting blood sample was collected to measure FSH. All participants underwent a dual X-ray absorptiometry scan to assess total and regional percent fat, lean mass (LM), fat mass (FM), bone mineral content (BMC), bone mineral density (BMD), and visceral adipose tissue (VAT) mass.

RESULTS

FSH was significantly higher in HCT recipients compared to non-HCT recipients and healthy controls. HCT recipients had significantly lower total body weight, total LM, arm and leg LM, BMC and BMD compared to non-HCT recipients and healthy controls (p < .05). Non-HCT recipients had significantly higher total, trunk, android, gynoid, arm and leg FM compared to healthy controls. Also, healthy controls had significantly lower VAT mass compared to non-HCT recipients.

CONCLUSIONS

This study's results show that HCT recipients have significant reductions in BMD, worse body composition, and abnormal FSH levels compared to non-HCT recipients and healthy controls.

Association of adiposity evaluated by anthropometric, BIA, and DXA measures with cardiometabolic risk factors in nonobese postmenopausal women: the CoLaus/OsteoLaus cohort

OBJECTIVE

After menopause, body composition changes with body fat accumulation, and an increase in cardiometabolic risk factors. Total fat mass, regional fat mass, and visceral adipose tissue (VAT) may be estimated with anthropometric measures, bioelectrical impedance analysis (BIA), and dual-energy X-ray absorptiometry (DXA). The aim of our study was to assess which measurement correlated best with cardiometabolic risk factors in healthy nonobese postmenopausal women.

METHODS

The CoLaus/OsteoLaus cohort included 1,500 postmenopausal women (age range 50-80). We analyzed correlations between: 1) measurements of body composition assessed by anthropometric measures, BIA, and DXA and 2) these measurements and different selected cardiometabolic risk factors, such as blood pressure, lipid markers (cholesterol subtypes and triglycerides), and metabolic markers (glucose, insulin, adiponectin, and leptin). Spearman correlation coefficient, stepwise forward regression, and linear regression analyses were used to determine association between anthropometric measurements and cardiometabolic risk factors.

RESULTS

In the 803 included participants (mean age 62.0 ± 7.1 y, mean body mass index 25.6 kg/m2 ± 4.4), correlations between total fat mass measured by BIA and total fat mass, android fat, gynoid fat, or VAT measured by DXA are very strong (from r = 0.531, [99% confidence interval (CI), 0.443-0.610] to r = 0.704, [99% CI, 0.640-0.758]). Body mass index and waist circumference have a higher correlation with VAT (r = 0.815, [99% CI, 0.772-0.851] and r = 0.823 [99% CI, 0.782-0.858], respectively) than BIA (r = 0.672 [99% CI, 0.603-0.731]). Among the anthropometric measurement and the measurements derived from DXA and BIA, VAT is the parameter most strongly associated with cardiometabolic risk factors. VAT better explains the variation of most of the cardiometabolic risk factors than age and treatment. For example, nearly 5% of the variability of the diastolic blood pressure (9.9 vs 4.9), nearly 15% of the variability of high-density lipoprotein cholesterol (20.3 vs 3.8) and triglyceride (21.1 vs 6.5), 25.3% of the variability of insulin (33.3 vs 8.1), and 37.5% of the variability of leptin (37.7 vs 1.1) were explained by VAT.

CONCLUSIONS

BIA seems not to be a good tool to assess VAT. At the population level, waist circumference and body mass index seem to be good tools to estimate VAT. VAT measured by DXA is the parameter most correlated with cardiometabolic risk factors and could become a component of the cardiometabolic marker on its own.

Association between body fat distribution and kidney stones: Evidence from a US population

OBJECTIVES

We aimed to evaluate the relationship between the proportion of Android to Gynoid ratio and the incidence of kidney stones among US adults.

METHODS

Participants aged 20-59 years from the 2011-2018 National Health and Nutrition Examination Survey (NHANES) database were selected to assess the association between Android to Gynoid ratio and kidney stone prevalence using logistic regression analysis, subgroup analysis and calculation of dose-response curves.

RESULTS

This study ultimately included 10858 participants, of whom 859 self-reported a history of kidney stones. And after adjusting for all confounders, an increased Android to Gynoid ratio was associated with an increased prevalence of kidney stones (OR=2.75, 95% CI:1.62-4.88). And subgroup analysis showed an increased prevalence of kidney stones in women (OR=3.55, 95% CI: 1.54-8.22), non-diabetic (OR=2.59, 95% CI: 1.45-4.60), 60 > age ≥ 40 years (OR=3.51, 95% CI: 1.83-6.71), Mexican-American (OR=4.35, 95% CI: 1.40- 13.53) and white (OR=3.86, 95% CI: 1.82-8.18) groups, there was a significant positive association between A/G ratio and kidney stones. In contrast, in the hypertensive subgroup, the A/G ratio was associated with kidney stones in all groups.

CONCLUSIONS

Higher Android to Gynoid ratio is associated with a high prevalence of kidney stone disease.

Body fat distribution and its risk for cardiovascular events in 10 years: Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

Body fat distribution seems to have different effects in cardiovascular diseases (CVD). We aimed to estimate the associations between lower limbs and trunk fat ratio and the 10-year CVD risk, and isolated risk factors in men and women. A total of 10,917 participants from ELSA-Brasil were eligible for this cross-sectional study. Associations between lower limb/trunk fat ratio with the percentage of 10-year CVD risk - according to the Framingham Risk Score - and its risk factors (systolic blood pressure, total cholesterol and HDL-cholesterol, diabetes, and use of antihypertensive medication) were performed using generalized linear models, linear and logistic regressions. All analyses were stratified by gender and adjustments were made by age, self-reported skin color, educational attainment, alcohol consumption, leisure physical activity, hypolipidemic drug use and, for women, menopausal status. In this study, 55.91% were women, with a mean age of 52.68 (SD = 6.57) years. A higher lower limb/trunk fat ratio was related to lower 10-year CVD risk, as well as a reduction in systolic blood pressure, total cholesterol, and antihypertensive drug use, also an increasing HDL-cholesterol in both genders, but this relationship was stronger in women. Besides, a protective relationship to diabetes was observed in women. Higher fat accumulation in the lower body, when compared to the trunk, seems to have a lower risk of CVD and associated risk factors - even in the presence of fat in the abdominal region - with women presenting lower risks than men.

The predictive value of trunk/leg fat ratio for type 2 diabetes mellitus remission after bariatric surgery: A new observation and insight

BACKGROUND

Emerging evidence supported the significant role of body composition and fat distribution in the etiology and pathogenesis of Type 2 diabetes mellitus (T2DM).

OBJECTIVE

To assess the predictive value of representative parameters of body composition and fat distribution for T2DM remission after bariatric surgery.

METHODS

A total of 72 patients with T2DM who underwent bariatric surgery in our center between September 2010 and December 2018 were included in this retrospective observational study. Diabetes remission was defined according to the American Diabetes Association criteria released in 2021. Body fat percentage, skeletal muscle index, Android/Gynoid ratio and trunk/leg fat ratio were derived from dual-energy X-ray absorptiometry and assessed.

RESULTS

A total of 40 patients (56%) achieved remission among 72 patients. Patients in the remission group had higher body fat percentage and lower trunk/leg fat ratio than those in the non-remission group. The area under the receiver operating characteristic curve (AUC) for predicting T2DM remission was higher for trunk/leg fat ratio (0.784), compared to BMI (AUC 0. 0.690) and body fat percentage (AUC 0.688). The prediction model (AUC 0.883) including age, duration of T2DM, and trunk/leg fat ratio performed better than the ABCD score (AUC 0.809) and the DiaRem score (AUC 0.792). A nonlinear relationship was observed between trunk/leg fat ratio and BMI.

CONCLUSION

Trunk/leg fat ratio is a promising predictor for T2DM remission after bariatric surgery.

Distinct opposing associations of upper and lower body fat depots with metabolic and cardiovascular disease risk markers

BACKGROUND

To examine the associations of total and regional adiposity with metabolic and cardiovascular disease (CVD) risk markers.

METHODS

This cross-sectional study included 1080 (53.8% men, aged 39-44 years) individuals from South India. Anthropometry (height, weight, waist and hip circumference), body composition assessment using dual-energy X-ray absorptiometry (DXA), blood pressure (BP), and plasma glucose, insulin and lipids were measured. Regression analysis was used to examine associations of standardized fat measurements with type 2 diabetes (T2D), insulin resistance (IR), hypertension and hypertriglyceridemia and continuous measurements of BP, glucose, insulin, HOMA-IR and lipids. Contour plots were constructed to visualize the differential effect of upper and lower fat depots.

RESULTS

DXA-measured fat depots were positively associated with metabolic and CVD risk markers. After adjusting for fat mass index, upper body fat remained positively, while lower body fat was negatively associated with risk markers. A one standard deviation (SD) increase in android fat showed higher odds ratios (ORs) for T2D (6.59; 95% CI 3.17, 13.70), IR (4.68; 95% CI 2.31, 9.50), hypertension (2.57; 95% CI 1.56, 4.25) and hypertriglyceridemia (6.39; 95% CI 3.46, 11.90) in men. A 1 SD increase in leg fat showed a protective effect with ORs for T2D (0.42; 95% CI 0.24, 0.74), IR (0.31; 95% CI 0.17, 0.57) and hypertriglyceridemia (0.61; 95% CI 0.38, 0.98). The magnitude of the effect was greater with DXA-measured fat compared with anthropometry.

CONCLUSION

At any level of total body fat, upper and lower body fat depots demonstrate opposite risk associations with metabolic and CVD risk markers in Asian Indians.

Socioeconomic position and body composition in childhood in high- and middle-income countries: a systematic review and narrative synthesis

BACKGROUND

The relation between socioeconomic position (SEP) and obesity measured by body mass index (BMI), a measure of weight for height, has been extensively reviewed in children, showing consistent associations between disadvantaged SEP and higher BMI in high-income countries (HICs) and lower BMI in middle-income countries (MICs). Fat mass (FM), a more accurate measure of adiposity, and fat-free mass (FFM) are not captured by BMI, but have been shown to track from childhood to adulthood, and be important for cardiovascular health and functional outcomes in later life. It is not clear whether body composition is associated with SEP. We systematically reviewed the association between SEP and body composition in childhood.

METHODS

A systematic review was carried out following PRISMA guidelines. The protocol was pre-registered with PROSPERO (CRD42019119937). Original studies in the English language, which examined the association between SEP and body composition in childhood, were included. An electronic search of three databases was conducted. Two independent reviewers carried out screening, data extraction and quality assessment. Due to heterogeneity in results, a narrative synthesis was conducted. Heterogeneity in findings according to SEP, sex, body composition measure and country income level was investigated.

RESULTS

50 papers were included, the majority from HICs. No papers were from low-income countries. Disadvantage in childhood was associated with greater FM and lower FFM in HICs, but with lower FM and lower FFM in MICs. When measures of FFM indexed to height were used there was no evidence of associations with SEP. In HICs, more studies reported associations between disadvantaged SEP and higher FM among girls comparative to boys.

CONCLUSIONS

Inequalities in FM are evident in HICs and, in the opposite direction, in MICs and follow similar trends to inequalities for BMI. Inequalities in height are likely important in understanding inequalities in FFM.

Anthropometric measures are satisfactory substitutes for the DXA-derived visceral adipose tissue in the association with cardiometabolic risk-The Tromsø Study 2015-2016

BACKGROUND

Body mass index (BMI) increases while cardiometabolic risk factors decrease in individuals in high-income countries. This paradoxical observation raises the question of whether current measures of overweight and obesity properly identify cardiometabolic risk.

METHODS

A total of 3675 participants (59% women) aged 40-84 years with whole-body dual-energy x-ray absorptiometry scans from the seventh survey of the Tromsø Study were included to examine the association between visceral adipose tissue (VAT) in grams and BMI, waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR). Further, their association with single cardiometabolic risk factors (blood pressure, triglycerides, total cholesterol, high-density lipoprotein [HDL] cholesterol, glycated hemoglobin, high-sensitivity C-reactive protein), modified single components from the ATP Ⅲ criteria for metabolic syndrome (hypertension, diabetes, high triglycerides, and low HDL cholesterol), and metabolic syndrome were examined.

RESULTS

VAT mass was strongly correlated with BMI (r ≥ 0.77), WC (r ≥ 0.80), WHR (r ≥ 0.58), and WHtR (r ≥ 0.78). WC was the strongest predictor for VAT (area under the curve: 0.90). Compared to anthropometric measures, the associations between VAT and metabolic syndrome as well as single components of metabolic syndrome were statistically significantly stronger, but the clinical differences were likely minor.

CONCLUSION

Although VAT mass showed statistically stronger associations with cardiometabolic risk compared to traditional anthropometrics, the clinical importance was likely small. Simple, clinically available tools seem to satisfactory substitute for VAT to identify cardiometabolic risk.

The association of glucocorticoid receptor polymorphism with metabolic outcomes in menopausal women with adrenal incidentalomas

OBJECTIVES

To investigate whether BclI polymorphism in the glucocorticoid receptor gene influences hypothalamic-pituitary-adrenal (HPA) axis regulation, body composition and metabolic parameters in women with adrenal incidentalomas (AIs).

STUDY DESIGN

A cross-sectional study.

MAIN OUTCOME MEASURES

We analyzed 106 women with AIs. Insulin resistance was assessed using a homeostasis model while HPA activity was assessed using dexamethasone suppression tests (DST), basal ACTH, urinary free cortisol, and midnight serum cortisol level. Body composition was analyzed using dual-energy X-ray absorptiometry. DNA was obtained from peripheral blood leucocytes and BclI polymorphism was detected using PCR, RFLP and DNA sequencing.

RESULTS

BclI carriers in comparison with those with wild-type BclI had less suppressed cortisol after DST-0.5 mg (126.4 ± 111.4 vs 80.9 ± 75.7 nmol/l, p = 0.026) and had a lower prevalence of impaired glucose tolerance and of type 2 diabetes mellitus (T2DM). BclI carriers had a higher percentage of leg fat mass (FM), lower left-sided limb muscle mass and a decline in total lean body mass. Duration of menopause remained a strong predictor of appendicular lean mass index (ALMI) (β=-0.125, p = 0.034). BclI polymorphism was significantly associated with sum of legs FM percentage (β=0.327, p = 0.048). T2DM was negatively associated with BclI polymorphism, after adjusting for age, truncal FM, ALMI, and sum of legs FM (OR=0.158, 95%CI 0.031-0.806, p = 0.027).

CONCLUSIONS

BclI polymorphism is associated with tissue-specific glucocorticoid sensitivity, relative glucocorticoid resistance of the HPA axis and peripheral adipose tissue, and glucocorticoid hypersensitivity at the muscle level. By modulating glucocorticoid and insulin sensitivity, BclI polymorphism appears to reduce the risk of T2DM in women with AIs.