Lean mass, and not fat mass, is an independent determinant of carotid intima media thickness in obese subjects

Lean body mass positively associate with blood pressure in Chinese adults: the roles of ages and body fat distribution

BACKGROUND

The relationship between lean body mass (LBM) and blood pressure (BP) is controversial and limited. This study investigated the associations between LBM indexes and BP in adults of different ages and with varying body fat distribution.

METHODS

The data for the present analysis was obtained from a cross-sectional survey of 1,465 adults (50.7% males) aged 18-70 years conducted in Beijing, China. Regional LBM and fat distribution, including fat mass (FM) and android to gynoid fat ratio (AOI), were assessed using a dual-energy X-ray bone densitometer. Generalized Liner Model (GLM) was employed. Confounders, including age, sex, height, weight, smoking, and alcohol use, were evaluated through questionnaires and physical examinations.

RESULTS

Males had higher rates of hypertension (11.19% vs. 4.92%) and prehypertension (21.57% vs. 14.59%) than females. The mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) were 122.04 mmHg and 76.68 mmHg. There were no significant associations between LBM and DBP (p > 0.05). However, arms LBM (β = 1.86, 95% CI: 0.77, 2.94) and trunk LBM (β = 0.37, 95% CI: 0.01, 0.73) were significantly associated with SBP. The association of LBM on DBP was stronger with increasing ages, and stronger in females than in males (p < 0.001). The association between adults' arms LBM and SBP was stronger in the high level FM group (β = 2.74 vs. β = 1.30) and high level AOI group (β = 1.80 vs. β = 2.08).

CONCLUSION

The influence of LBM on SBP increases with age, particularly after the age twenty years in females. For adults with high FM or high AOI, LBM in the arms, showed a stronger positive predictive association with SBP. This suggests that, in addition to controlling fat content, future efforts to improve cardiovascular health in adults should include the management of LBM (especially in the upper body).

The Interconnection between Carotid Intima-Media Thickness and Obesity: Anthropometric, Clinical and Biochemical Correlations

Background and Objectives: Carotid intima-media thickness (CIMT) and obesity are considered independent determinants of cardio- and cerebrovascular events. The aim of our study was to investigate the effect of obesity on CIMT and to define which traditional cardiovascular risk factors correlate the most with CIMT values in patients with obesity. Materials and Methods: Anthropometric measurements were collected for the whole study group, as well as body composition and blood pressure data, and biochemical blood analyses were also performed. Results: Although our study group was significantly older according to vascular compared with chronological age, the mean CIMT values were lower when compared with the reference values. We found a statistically significant correlation of CIMT with chronological and vascular age, systolic blood pressure, fasting glucose, total cholesterol and triglyceride levels, waist-to-hip ratio, waist circumference, body muscle mass and skeletal muscle mass index. Atherosclerotic Cardiovascular Disease (ASCVD) risk assessment and SCORE (Systematic COronary Risk Evaluation) showed significant positive correlations, but there was only a weak correlation of ASCVD with CIMT. Conclusions: To deduce, since no diagnostic tool currently includes body weight as an individual risk factor, further trials are highly needed to determine if SCORE, SCORE2, ASCVD risk assessment or CIMT would be the most accurate and relevant diagnostic tool for prediction of risk for future CV events in patients with obesity.

Associations between the Combined Fat Mass Index and Fat-Free Mass Index with Carotid Intima-Media Thickness in a Japanese Population: The Tohoku Medical Megabank Community-Based Cohort Study

AIM

Although many epidemiological studies have shown that obesity assessed by body mass index is associated with carotid intima-media thickness (cIMT), few studies have evaluated fat-free mass, which is a component of body composition. We investigated the associations between the combined fat mass index (FMI) and fat-free mass index (FFMI) with cIMT.

METHODS

We conducted a cross-sectional study of 3,873 men and 9,112 women aged 20 years or older who lived in Miyagi prefecture, Japan. The FMI and FFMI were calculated as fat mass and fat-free mass divided by height squared, respectively. The indices were classified into sex-specific quartiles and were combined into 16 groups. The maximum common carotid artery was measured using high-resolution B-mode ultrasound. An analysis of covariance was used to assess associations between the combined FMI and FFMI with cIMT adjusted for age and smoking status. The linear trend test was conducted by stratifying the FMI and FFMI, scoring the categories from 1 (lowest) to 4 (highest), and entering the number as a continuous term in the regression model.

RESULTS

In multivariable models, a higher FMI was not related to higher cIMT in men and women in most FFMI subgroups. Conversely, a higher FFMI was related to higher cIMT in all FMI subgroups (p＜0.001 for linear trend).

CONCLUSIONS

FMI was not associated with cIMT in most FFMI subgroups. Conversely, FFMI was positively associated with cIMT independently of FMI.

Body fat, pericardial fat, liver fat and arterial health at age 10 years

BACKGROUND

Body mass index is associated with carotid intima-media thickness and distensibility in adults and children.

OBJECTIVE

To examine whether general and specific fat depots are associated with these markers of arterial health at school age.

METHODS

This cross-sectional analysis was embedded in a population-based prospective cohort study among 4708 children aged 10 years. Body, lean and fat mass index were estimated by dual-energy X-ray absorptiometry. Pericardial, visceral and liver fat were estimated by magnetic resonance imaging. Carotid intima-media thickness and distensibility were measured by ultrasound.

RESULTS

A 1-standard-deviation-score (SDS) higher body mass index was associated with higher carotid intima-media thickness (0.06 SDS, 95% confidence interval [CI]: 0.03-0.08) and lower distensibility (-0.17 SDS, 95% CI: -0.20 to -0.14). These associations tended to be similar for lean mass index. A 1-SDS higher fat mass index was associated with lower carotid intima-media thickness (-0.08 SDS, 95% CI: -0.11 to -0.05) and lower distensibility (-0.10 SDS, 95% CI: -0.14 to -0.07). A 1-SDS higher liver fat fraction was associated with lower carotid intima-media thickness (-0.04 SDS, 95% CI: -0.08 to -0.00) and lower distensibility (-0.06 SDS, 95% CI: -0.10 to -0.03). We observed similar associations for visceral fat.

CONCLUSIONS

At school age, lean and fat mass seem to be differentially related to carotid intima-media thickness but not distensibility. Arterial development might be affected by lean mass, general and specific fat mass.

Fat-Free Mass Index, Visceral Fat Level, and Muscle Mass Percentage Better Explain Deviations From the Expected Value of Aortic Pressure and Structural and Functional Arterial Properties Than Body Fat Indexes

Bioelectrical impedance analysis (BIA)-derived indexes [e.g., fat (FMI) and fat-free mass indexes (FFMI), visceral fat level (VFL)] are used to characterize obesity as a cardiovascular risk factor (CRF). The BIA-derived index that better predicts arterial variability is still discussed.

A prospective cohort study on the association of lean body mass estimated by mid-upper arm muscle circumference with hypertension risk in Chinese residents

The associations of lean body mass (LBM) with elevated blood pressure (BP) and hypertension were controversial, and the causalities have never been shown. Mid-upper arm muscle circumference (MAMC), an easily obtained anthropometric measurement, could provide an accurate estimate for LBM. Therefore, a prospective cohort study in general Chinese residents aiming to find out the relationship between LBM estimated using MAMC and hypertension risk was performed. Eight thousand one hundred eighty-five eligible participants were included in the baseline analysis, among whom 3442 were subsequently selected into cohort analysis. MAMC was calculated using mid-upper arm circumference (MUAC) and triceps skinfold thickness (TST). Associations of MAMC with BP values and hypertension prevalence were estimated by linear and logistic regression models. Associations with hypertension incidence were estimated by COX regression models, hazard ratio (HR) and 95% confidence interval (CI) were given. Nonlinear relationship between MAMC and hypertension risk was estimated using restricted cubic spline method. Standardized coefficients of MUAC and TST were compared to estimate their strengths of associations with hypertension. Baseline analysis showed that after adjusted for confounders, the increase of systolic BP per standard deviation (SD) of MAMC were 1.97 mmHg (95%CI: 1.46, 2.48) and 1.63 mmHg (95%CI: 1.10, 2.16) respectively in men and women, and the increases of diastolic BP per SD were 1.58 mmHg (95%CI: 1.23, 1.92) and 1.08 mmHg (95%CI: 0.74, 1.42). Additionally, the association of MAMC with the prevalence of hypertension were also found in both men and women (OR = 1.36, 95%CI: 1.26, 1.47 in men; OR = 1.33, 95%CI: 1.22, 1.44 in women). Cohort analysis showed that MAMC increased the risk of hypertension (HR = 1.10, 95%CI: 1.01, 1.19 for men; HR = 1.15, 95%CI: 1.06, 1.26 for women), and a trend of J-shaped relationship was found. Additionally, the stronger associations of MUAC with both BP values and hypertension than that of TST were found in both baseline and cohort analyses. Findings in our study implied that we cannot neglect the capacity of LBM in predicting hypertension risk, and LBM estimates should be recommended in general health surveys or examinations.

Childhood vascular phenotypes have differing associations with prenatal and postnatal growth

OBJECTIVE

In children aged 8--9 years, we examined the associations of linear and abdominal circumference growth during critical stages of prenatal and postnatal development with six vascular measurements commonly used as early markers of atherosclerosis and later cardiovascular disease (CVD) risk.

METHODS

In 724 children from the UK Southampton Women's Survey mother--offspring cohort, offspring length/height and abdominal circumference measurements were collected at 10 ages between 11 weeks' gestation and age 8--9 years. Using residual growth modelling and linear regression, we examined the independent associations between growth and detailed vascular measures made at 8--9 years.

RESULTS

Postnatal linear and abdominal circumference growth were associated with higher childhood SBP and carotid--femoral pulse wave velocity, whereas prenatal growth was not. For example, 1SD faster abdominal circumference gain between ages 3 and 6 years was associated with 2.27 [95% confidence interval (CI): 1.56--2.98] mmHg higher SBP. In contrast, faster abdominal circumference gain before 19 weeks' gestation was associated with greater carotid intima--media thickness [0.009 mm (0.004--0.015) per 1SD larger 19-week abdominal circumference), whereas later growth was not. We found no strong associations between prenatal or postnatal growth and DBP or measures of endothelial function.

CONCLUSION

Higher postnatal linear growth and adiposity gain are related to higher SBP and carotid--femoral pulse wave velocity in childhood. In contrast, faster growth in early gestation is associated with greater childhood carotid intima--media thickness, perhaps resulting from subtle changes in vascular structure that reflect physiological adaptations rather than subclinical atherosclerosis.

Relationships between carotid artery intima-media thickness and echogenicity and body composition using a new magnetic resonance imaging voxel-based technique

BACKGROUND

We evaluated how carotid artery intima-media thickness (IMT) and the echogenicity of the intima-media (IM-GSM), measured by ultrasound, were related to body composition, evaluated by both traditional imaging techniques, as well as with a new voxel-based "Imiomics" technique.

METHODS

In 321 subjects all aged 50 years in the POEM study, IMT and IM-GSM were measured together with a DXA scan for determination of fat and lean mass. Also a whole-body MRI scan was performed and the body volume was divided into >1 million voxels in a standardized fashion. IMT and IM-GSM were related to each of these voxels to create a 3D-view of how these measurements were related to size of each part of the body.

RESULTS

IM-GSM was inversely related to almost all traditional measurements of body composition, like fat and lean mass, liver fat, visceral and subcutaneous fat, but this was not seen for IMT. Using Imiomics, IMT was positively related to the intraabdominal fat volume, as well of the leg skeletal muscle in women. In males, IMT was mainly positively related to the leg skeletal muscle volume. IM-GSM was inversely related to the volume of the SAT in the upper part of the body, leg skeletal muscle, the liver and intraabdominal fat in both men and women.

CONCLUSION

The voxel-based Imiomics technique provided a detailed view of how the echogenicity of the carotid artery wall was related to body composition, being inversely related to the volume of the major fat depots, as well as leg skeletal muscle.

Determinants of Intima-Media Thickness in the Young: The ALSPAC Study

OBJECTIVES

This study characterized the determinants of carotid intima-media thickness (cIMT) in a large (n > 4,000) longitudinal cohort of healthy young people age 9 to 21 years.

BACKGROUND

Greater cIMT is commonly used in the young as a marker of subclinical atherosclerosis, but its evolution at this age is still poorly understood.

METHODS

Associations between cardiovascular risk factors and cIMT were investigated in both longitudinal (ages 9 to 17 years) and cross-sectional (ages 17 and 21 years) analyses, with the latter also related to other measures of carotid structure and stress. Additional use of ultra-high frequency ultrasound in the radial artery at age 21 years allowed investigation of the distinct layers (i.e., intima or media) that may underlie observed differences.

RESULTS

Fat-free mass (FFM) and systolic blood pressure were the only modifiable risk factors positively associated with cIMT (e.g., mean difference in cIMT per 1-SD increase in FFM at age 17: 0.007 mm: 95% confidence interval [CI]: 0.004 to 0.010; p < 0.001), whereas fat mass was negatively associated with cIMT (difference: -0.0032; 95% CI: 0.004 to -0.001; p = 0.001). Similar results were obtained when investigating cumulative exposure to these factors throughout adolescence. An increase in cIMT maintained circumferential wall stress in the face of increased mean arterial pressure when increases in body mass were attributable to increased FFM, but not fat mass. Risk factor-associated differences in the radial artery occurred in the media alone, and there was little evidence of a relationship between intimal thickness and any risk factor.

CONCLUSIONS

Subtle changes in cIMT in the young may predominantly involve the media and represent physiological adaptations as opposed to subclinical atherosclerosis. Other vascular measures may be more appropriate for the identification of arterial disease before adulthood.

Longitudinal effects of smoking cessation on carotid artery atherosclerosis in contemporary smokers: The Wisconsin Smokers Health Study

BACKGROUND AND AIMS

We quantified the effects of smoking and smoking cessation on carotid artery atherosclerosis and wall thickness in two unique cohorts of smokers making a quit attempt.

METHODS

Our primary analysis included 726 smokers making a quit attempt in a randomized clinical trial with long-term follow-up. Our secondary analysis included 889 smokers making a quit attempt in a subsequent trial. Participants underwent carotid artery ultrasonography at baseline and up to 3 subsequent visits. Primary outcomes were changes in carotid plaque score and intima media-thickness (IMT). We calculated a smoking burden score (SBS) that reflected the number of visits in which participants reported smoking after the quit attempt. Multivariable regression examined relations between SBS and carotid artery outcomes with adjustments for cardiovascular disease risk factors.

RESULTS

In the primary analysis, participants were mean (standard deviation) 46.1 (10.3) years old (57.9% female) and smoked 21.1 (8.9) cigarettes per day (CPD). After a median of 7 years, lower SBS predicted less increase in carotid plaque score (Chi-squared = 13.0, p = 0.012). SBS independently predicted change in carotid plaque score (p = 0.007; SBS 0 vs 4) as did baseline CPD (p = 0.024) and age (p<0.0001). SBS did not affect carotid IMT change. In the secondary analysis, increasing SBS was associated with increased likelihood of new plaques over 3 years among participants that smoked ≥15 CPD, (Chi-squared = 6.51, p = 0.011).

CONCLUSIONS

Smoking cessation is associated with less progression of carotid plaque, but not IMT. Salutary associations of smoking cessation with carotid plaque progression are related to degree of abstinence.

Lean body mass is the strongest anthropometric predictor of left ventricular mass in the obese paediatric population

BACKGROUND

Indexing left ventricular mass to body surface area or height2.7 leads to inaccuracies in diagnosing left ventricular hypertrophy in obese children. Lean body mass predictive equations provide the opportunity to determine the utility of lean body mass in indexing left ventricular mass. Our objectives were to compare the diagnostic accuracy of predicted lean body mass, body surface area, and height in detecting abnormal left ventricle mass in obese children.

METHODS

Obese non-hypertensive patients aged 4-21 years were recruited prospectively. Dual-energy X-ray absorptiometry was used to measure lean body mass. Height, weight, sex, race, and body mass index z-score were used to calculate predicted lean body mass.

RESULTS

We enrolled 328 patients. Average age was 12.6 ± 3.8 years. Measured lean body mass had the strongest relationship with left ventricular mass (R2 = 0.84, p < 0.01) compared to predicted lean body mass (R2 = 0.82, p < 0.01), body surface area (R2 = 0.80, p < 0.01), and height2.7 (R2 = 0.65, p < 0.01). Of the clinically derived variables, predicted lean body mass was the only measure to have an independent association with left ventricular mass (β = 0.90, p < 0.01). Predicted lean body mass was the most accurate scaling variable in detecting left ventricular hypertrophy (positive predictive value = 88%, negative predictive value = 99%).

CONCLUSIONS

Lean body mass is the strongest predictor of left ventricular mass in obese children. Predicted lean body mass is the most accurate anthropometric scaling variable for left ventricular mass in left ventricular hypertrophy detection. Predicted lean body mass should be considered for clinical use as the body size correcting variable for left ventricular mass in obese children.

Does lean body mass equal health despite body mass index?

OBJECTIVE

To determine the association between having simultaneously high body mass index (BMI) and high relative lean body mass (LBM) and cardio-metabolic risk factors, metabolic syndrome (MetS), and diabetes in adults.

MATERIALS AND METHODS

A cross-sectional analysis was performed on 4982 adults aged 19-85 years that participated in the National Health and Nutrition Examination Survey (cycles 1999-2000-2005-2006). The primary exposure variable was categorization into four groups: (a) Low-BMI/Low-LBM, (b) Low-BMI/High-LBM, (c) High-BMI/Low-LBM, and (d) High-BMI/High-LBM. LBM was assessed using dual-energy X-ray absorptiometry. The primary outcome measures were cardio-metabolic risk factors, MetS based on the ATP III definition; participants were required to have at least three of the following five criteria: high waist circumference, low HDL cholesterol, elevated triglyceride levels, high resting blood pressure, and self-reported diabetes.

RESULTS

Compared to the High-BMI/High-LBM, most cardio-metabolic risk factors were significantly different among groups (P < .05) while no such differences were observed for the High-BMI/Low-LBM (P > .05). Exception of waist circumference (OR [95%]: 21.8 [8.84-53.82]), there was no increased odds of having cardio-metabolic risk factors in the High-BMI/Low-LBM compared with the High-BMI/High-LBM (P > .05). The odds of having MetS and diabetes for the High-BMI/Low-LBM compared with the High-BMI/High-LBM were OR (95% CI): 1.68 (0.84-3.36) and 0.59 (0.26-1.34), respectively.

CONCLUSIONS

Our results suggest that having a high-BMI as well as high relative LBM levels is not associated with cardio-metabolic risk factors, MetS, and diabetes. Therefore, maintaining a BMI below 30 kg/m² appears to be clinically relevant, regardless of LBM levels.

Alanine Aminotransferase and Body Composition in Obese Men and Women

There is a known relationship between serum alanine aminotransferase (ALT) and obesity in humans, but the mechanism(s) are not clarified. This study investigated the associations between serum ALT and body composition in an overweight and obese population. The results are based on data from a previous randomized controlled trial treating obesity with vitamin D₃. A sample of 448 overweight and obese individuals underwent dual-energy X-ray absorptiometry (DEXA) and measured serum ALT along with supplementary blood samples at study baseline. Body fat mass and lean mass indexes were calculated by dividing total body fat/lean weight (kg) by body height squared (kg/m²). ALT correlated with body mass index (BMI) in men but not women (r = 0.33, P < 0.0001 vs. r = 0.06, P = 0.29). In men, serum ALT correlated positively with fat mass index (r = 0.23, P = 0.004) and lean mass index (r = 0.32, P < 0.0001). In women, ALT correlated with lean mass index (r = 0.13, P = 0.031) but not fat mass index (r = 0.003, P = 0.96). In a multivariate model adjusted for age and fat mass index, a 1-unit increase in lean mass index associated with a 0.37 U/L higher ALT in the male subgroup (95% CI 0.024 to 0.040, P < 0.0001). In conclusion, serum ALT was associated with body fat mass index in men and with lean mass index in men and women in an overweight and obese population. The findings also demonstrate a gender difference in the role of fat.

Carotid Intima-Media Thickness but Not Carotid Artery Plaque in Healthy Individuals Is Linked to Lean Body Mass

Background Lean body mass has been identified as a key determinant of left ventricular mass and wall thickness. However, the importance of lean body mass or other body-size measures as normative determinants of carotid intima-media thickness (cIMT), a widely used early indicator of atherosclerosis, has not been well established. Methods and Results Carotid artery ultrasound measurements of cIMT and carotid artery plaque burden (derived from plaque number and maximum size) and measurements of body size, including height, body mass index, weight, body fat proportion, and lean body mass ([1-body fat proportion]×weight), were recorded in 25 020 participants from 10 regions of China. Analyses were restricted to a healthy younger subset (n=6617) defined as never or long-term ex-regular smokers aged <60 years (mean age, 50) without previous ischemic heart disease, stroke, diabetes mellitus, or hypertension and with plasma non-high-density lipoprotein cholesterol <4 mmol/L. Among these 6617 participants, 86% were women (because most men smoked) and 9% had carotid artery plaque. In both women and men separately, lean body mass was strongly positively associated with cIMT, but was not associated with plaque burden: overall, each 10 kg higher lean body mass was associated with a 0.03 (95% CI, 0.03-0.04) mm higher cIMT (P=5×10-33). Fat mass, height, and other body-size measures were more weakly associated with cIMT. Conclusions The strong association of lean body mass with cIMT, but not with plaque burden, in healthy adults suggests a normative relationship rather than reflecting atherosclerotic pathology. Common mechanisms may underlie the associations of lean body mass with cIMT and with nonatherosclerotic vascular traits.

Obesity, dynapenia and high cardiovascular risk co-exist in post-liver transplant setting: results of a cross-sectional study

BACKGROUND

Cardiovascular disease is a major cause of death in post-liver transplantation (LT). The aim of this study was to evaluate LT patients as to the carotid intima-media thickness (CIMT) and its association with nutritional status, dietary intake, metabolic profile and cardiovascular risk factors.

METHODS

In this cross-sectional study, adult patients with more than 12 months of post-transplant follow-up underwent clinical, laboratory, functional and nutritional evaluation by 3-day-diet-record, anthropometry and dynamometry. CIMT was evaluated by Doppler ultrasonography.

RESULTS

Sixty-nine post-LT patients [males 61%, median of age 59 (51-64) years were included; median time post-liver transplantation 2.8 (1.4-6.3) years]. High prevalence of malnutrition was found (45% of arm muscle area < p15 and 71% of handgrip strength < p30). Excess weight was present in 72% of patients, body mass index ≥ 30 kg/m² in 35% and metabolic syndrome in 51%. Abnormal CIMT was found in 54% of the sample. Patients with abnormal CIMT presented higher cardiovascular risk Score, LDL cholesterol, higher prevalence of high-sensitive C-reactive protein ≥ 1 mg/L and higher intake of saturated and trans fatty acids (P < 0.05 for all).

CONCLUSIONS

Abnormal IMT was commonly found in LT patients presenting at the same time with overweight and dynapemia. These results were associated with higher LDL-cholesterol levels, high-sensitive C-reactive protein ≥ 1 mg/L and higher intake of saturated and trans fatty acids. Preventive measures, including dietary advice, are required for all post-liver transplantation patients to minimize cardiovascular risk.

Associations of Body Composition with Blood Pressure and Hypertension

OBJECTIVE

The present study investigated the associations of body composition, including skeletal muscle and fat mass, with blood pressure (BP) and hypertension.

METHODS

Data from 3,130 participants aged 18 to 80 years were analyzed. Body composition and total skeletal muscle (TSM) were measured or calculated based on dual-energy x-ray absorptiometry. Multivariate linear and logistic regression models were used to analyze the associations of TSM, body fat percentage, android to gynoid fat ratio, and leg and arm lean body mass (LBM) with BP and hypertension. The Wald test was used to estimate the differences in the coefficients.

RESULTS

TSM indices, body fat percentage, and android to gynoid fat ratio were significantly associated with higher odds ratio for prehypertension and hypertension, except for TSM/weight, after controlling for potential confounders. The standardized beta coefficients of arm LBM indices for systolic and diastolic BP were higher than relevant indices of leg LBM.

CONCLUSIONS

Different indices of TSM, especially in arm LBM, were all positively associated with elevated BP, prehypertension, and hypertension in Chinese adults, after considering potential confounding factors, including body fat and fat distribution. Future longitudinal studies are warranted to confirm our findings.

Childhood Fat and Lean Mass: Differing Relations to Vascular Structure and Function at Age 8 to 9 Years

Objective- Childhood body mass index (BMI) has been related to vascular structure and function. However, little is known about the differing contributions of fat and lean mass to this relationship. Our objectives were to relate the fat and lean mass (bone excluded) components of BMI (fat mass index and lean mass index; mass [kg]/height [m]2) to vascular measures in prepubertal children. Approach and Results- In the UK Southampton Women's Survey mother-offspring cohort, 983 children had dual x-ray absorptiometry and vascular measurements at 8 to 9 years. Using linear regression analyses, we found that most vascular measures were related to BMI, but fat and lean mass contributed differently. Systolic blood pressure was positively associated with both fat mass index (β=0.91 [95% CI, 0.52-1.30] mm Hg) and lean mass index (β=2.16 [95% CI, 1.47-2.85] mm Hg), whereas pulse rate was positively associated with fat mass index (β=0.93 [95% CI, 0.48-1.38] b/min) but negatively associated with lean mass index (β=-1.79 [95% CI, -2.59 to -0.99] b/min). The positive relation between BMI and carotid intima-media thickness was mainly due to a positive association with lean mass index (β=0.013 [95% CI, 0.008-0.019] mm). Carotid-femoral pulse wave velocity, but not carotid-radial pulse wave velocity, was positively associated with fat mass index (β=0.06 [95% CI, 0.03-0.09] m/s). For systolic blood pressure, carotid-femoral pulse wave velocity and reactive hyperemia significant interactions indicated that the association with fat mass depended on the amount of lean mass. Conclusions- In prepubertal children, differences in vascular structure and function in relation to BMI probably represent combinations of adverse effects of fat mass, adaptive effects of body size, and relatively protective effects of lean mass.

Lean body mass and creatine kinase are associated with reduced inflammation in obesity

BACKGROUND

Obesity is associated with inflammation, but the role of lean mass and creatine kinase (CK) on the inflammatory process is less known. We investigated the associations between lean mass, CK and fat mass upon inflammatory parameters in an overweight and obese adult population.

MATERIAL AND METHODS

Body composition examined by dual-energy X-ray absorptiometry, high-sensitivity C-reactive protein (hs-CRP), erythrocyte sedimentation rate (ESR), CK and supplementary clinical parameters were measured in 454 overweight and obese individuals. This is a secondary analysis from a cohort of obese individuals treated with Vitamin D.

RESULTS

Mean age was 47·6 ± 11·4 years and mean body mass index 34·6 ± 3·9 kg/m² . Lean mass correlated negatively with hs-CRP (r = -0·127, P = 0·042) and ESR (r = -0·381, P < 0·001). Median lean mass in the lower ESR quartile was significantly higher than in the upper quartile (P < 0·001) but not between lower and upper hs-CRP quartiles (P = 0·114). CK was negatively correlated with hs-CRP (r = -0·151, P < 0·001) and ESR (r = -0·240, P < 0·001). Median CK in the lower hs-CRP and ESR quartiles were significantly higher than in the upper quartiles (P < 0·001 for both). Conversely, fat mass was positively associated with hs-CRP and ESR.

CONCLUSIONS

Inflammatory parameters were related to reduced lean mass and CK in an overweight and obese population. Hypothetically, lean mass has a favourable effect on obesity-related inflammation, and CK may play a role as an inhibitor of inflammation in obesity.

The associations of body composition and anthropometric measures with carotid intima-media thickness in obese and non-obese schoolchildren: A possible predictor for cardiovascular diseases

Background

Increased carotid intima-media thickness is one of the predictors of future cardiovascular diseases. However, it is still unknown which body composition parameter or anthropometric measure is the best predictor for carotid intima-media thickness change among children and young adolescents.

Objective

To investigate the associations of body composition and anthropometric measures with carotid intima-media thickness among a group of obese and normal bodyweight schoolchildren.

Methods

A total of 125 schoolchildren (10–15 years) were recruited from four public schools in Amman, Jordan. Of them, 60 (29 boys and 31 girls) were normal bodyweight students and 65 (35 boys and 30 girls) were obese students. Anthropometric measures, fat mass and fat-free mass were determined. Carotid intima-media thickness of the common artery was measured using high-resolution B-mode ultrasound.

Results

Compared to normal bodyweight students, obese participants exhibited greater carotid intima-media thickness (mm) (0.45 ± 0.10 vs. 0.38 ± 0.08, p = 0.002) and fat-free mass (kg) (48.01 ± 11.39 vs. 32.65 ±7.65, p < 0.001). Pearson’s correlation coefficient and linear regression analysis revealed significant associations ( p≤0.05) between mean carotid intima-media thickness and body mass index, waist circumference, hip circumference, waist-to-hip ratio, fat mass and fat-free mass. Stepwise linear regression analysis revealed that waist circumference was the only measure that was statistically significant ( p ≤ 0.05) with mean carotid intima-media thickness (r2 = 0.129, p = 0.002).

Conclusions

Obesity is related to greater carotid intima-media thickness and other cardiovascular risk factors among schoolchildren. Waist circumference is more sensitive in predicting increased carotid intima-media thickness than other body composition or anthropometric measures. Waist circumference measurement in the analysis of future studies assessing the cardiovascular risk among obese children is warranted.

Expression of Metabolic Syndrome in Women with Severe Obesity

BACKGROUND

The prevalence of metabolic syndrome (MetS) generally rises with increasing adiposity, but tends to plateau at the highest levels of body mass index (BMI) with some individuals, even with severe obesity, expressing few or no components of MetS. We examined factors associated with the expression of MetS in severely obese women participating in a large observational study.

METHODS

Anthropometrics, including Heath equation-adjusted bioimpedance-determined fat-free mass (FFM) and fat mass (FM), lipids and related laboratory measurements, resting energy expenditure (REE), and respiratory quotient (RQ), were studied in 949 women with severe obesity.

RESULTS

Even though the mean BMI was 45.7 kg/m² and all participants met MetS criteria for increased waist circumference, 30% of subjects did not have MetS. Unadjusted FM (P = 0.0011), FFM (P < 0.0001), and REE (P < 0.0001) were greater in the women with MetS. Surprisingly, in multivariate logistic regression FFM was positively associated with MetS (P = 0.0002), while FM was not (P = 0.89). Moreover, FFM, not FM, was significantly associated with all five components of MetS except for triglyceride levels. REE and RQ were higher in those with MetS, and REE was strongly associated with multiple components of MetS.

CONCLUSIONS

In women with severe obesity, higher FFM and REE were paradoxically associated with increased rather than decreased risk of MetS, while FFM-adjusted FM was unrelated to MetS.

Obesity and Cardiovascular Disease

The prevalence of obesity has increased worldwide over the past few decades. In 2013, the prevalence of obesity exceeded the 50% of the adult population in some countries from Oceania, North Africa, and Middle East. Lower but still alarmingly high prevalence was observed in North America (≈30%) and in Western Europe (≈20%). These figures are of serious concern because of the strong link between obesity and disease. In the present review, we summarize the current evidence on the relationship of obesity with cardiovascular disease (CVD), discussing how both the degree and the duration of obesity affect CVD. Although in the general population, obesity and, especially, severe obesity are consistently and strongly related with higher risk of CVD incidence and mortality, the one-size-fits-all approach should not be used with obesity. There are relevant factors largely affecting the CVD prognosis of obese individuals. In this context, we thoroughly discuss important concepts such as the fat-but-fit paradigm, the metabolically healthy but obese (MHO) phenotype and the obesity paradox in patients with CVD. About the MHO phenotype and its CVD prognosis, available data have provided mixed findings, what could be partially because of the adjustment or not for key confounders such as cardiorespiratory fitness, and to the lack of consensus on the MHO definition. In the present review, we propose a scientifically based harmonized definition of MHO, which will hopefully contribute to more comparable data in the future and a better understanding on the MHO subgroup and its CVD prognosis.

Body Mass Index, the Most Widely Used But Also Widely Criticized Index: Would a Criterion Standard Measure of Total Body Fat Be a Better Predictor of Cardiovascular Disease Mortality?

OBJECTIVES

To examine whether an accurate measure (using a criterion standard method) of total body fat would be a better predictor of cardiovascular disease (CVD) mortality than body mass index (BMI).

PARTICIPANTS AND METHODS

A total of 60,335 participants were examined between January 1, 1979, and December 31, 2003, and then followed-up for a mean follow-up period of 15.2 years. Body mass index was estimated using standard procedures. Body composition indices (ie, body fat percentage [BF%], fat mass index [FMI], fat-free mass [FFM], and FFM index [FFMI]) were derived from either skinfold thicknesses or hydrostatic weighing. For exact comparisons, the indices studied were categorized identically using sex-specific percentiles.

RESULTS

Compared with a medium BMI, a very high BMI was associated with a hazard ratio (HR) of 2.7 (95% CI, 2.1-3.3) for CVD mortality, which was a stronger association than for BF% or FMI (ie, HR, 1.6; 95% CI, 1.3-1.9 and HR, 2.2; 95% CI, 1.8-2.7, respectively). Compared with a medium FFMI, a very high FFMI was associated with an HR of 2.2 (95% CI, 1.7-2.7) for CVD mortality, with these estimates being markedly smaller for FFM (ie, HR, 1.2; 95% CI, 0.9-1.6). When the analyses were restricted only to the sample assessed with hydrostatic weighing (N=29,959, 51.7%), the results were similar, with even slightly larger differences in favor of BMI (ie, HR, 3.0; 95% CI, 2.2-4.0) compared with BF% and FMI (ie, HR, 1.5; 95% CI, 1.2-1.9 and HR, 2.1; 95% CI, 1.6-2.7, respectively). We estimated Harrell's c-index as an indicator of discriminating/predictive ability of these models and observed that the c-index for models including BMI was significantly higher than that for models including BF% or FMI (P<.005 for all).

CONCLUSION

The simple and inexpensive measure of BMI can be as clinically important as, or even more than, total adiposity measures assessed using accurate, complex, and expensive methods. Physiological explanations for these findings are discussed.