Body fat and skeletal muscle mass in relation to physical disability in very old men and women of the Framingham Heart Study

BACKGROUND: Low muscle mass has been assumed to be associated with disability, but no studies confirming this association have been published. High body weight and high body mass index, both rough indicators of body fatness, have been shown to increase the risk for disability; however, the specific role of body fatness has not been studied. METHODS: The relations of skeletal muscle mass and percent body fat with self-reported physical disability were studied in 753 men and women aged 72 to 95 years. Cross-sectional data from biennial examination 22 (1992-1993) of the Framingham Heart Study were used. Body composition was assessed by dual-energy x-ray absorptiometry. Disability was scored as any versus none on a 9-item questionnaire. RESULTS: Total body and lower extremity muscle mass were not associated with disability in either men or women. However, a strong positive association between percent body fat and disability was observed. The odds ratio for disability in those in the highest tertile of body fatness was 2.69 (95% confidence interval 1.45-5.00) for women and 3.08 (1.22-7.81) for men compared to those in the lowest tertile. The increased risk could not be explained by age, education, physical activity, smoking, alcohol use, estrogen use (women only), muscle mass, and health status. Analyses restricting disability to mobility items gave similar results. CONCLUSIONS: In contrast to current assumptions, low skeletal muscle mass was not associated with self-reported physical disability. Persons with a high percent body fat had high levels of disability. Because it cannot be ruled out that persons with low skeletal muscle mass dropped out earlier in the study, prospective studies are needed to further assess the relationship between body composition and physical disability.     

Shifts of visual spatial attention modulate a steady-state visual evoked potential

An uncertain relation between health and angry/hostile behaviour exists in the literature on adolescents. With data from a pilot study, one possible reason for this is explored: health measures such as blood pressure as well as angry/hostile behaviours may change with, or depend upon physical maturity, body size and body fatness. The sample consists of 60 African-, Hispanic-, and Anglo-American adolescents (15 to 16 years of age) drawn from a public school in Houston, TX. Using resting diastolic blood pressure as a model, in a sex stratified analysis, the following conclusions were reached: Physical maturity in girls and body height in boys were related to ethnicity in the sample and were confounders of the blood pressure and anger relationship. In girls secretive anger ('anger-in') and hostility were associated with increased body fat; expressive anger ('anger-out') in boys is associated with increased conicity (central body fat distribution) (p < 0.01). These associations were independent of height and physical maturity. Hostility was not significantly related to diastolic blood pressure in boys after adjusting for height and conicity. 'Anger-in' was significantly and positively related to diastolic blood pressure in girls (p < 0.01). This relationship was strongly mediated by per cent body fat, because the association of 'anger-in' and blood pressure was no longer statistically significant when the model included body fat. The results suggest that measures of physical maturity and more refined measures of body fat and body fat distribution should be considered in studies attempting to link adolescent blood pressure with anger expression.     

Quantifying gender differences in physical performance: A developmental perspective.

The purpose was to quantify the contribution of anthropometric variables to gender differences in performance during childhood and adolescence. Measures of height, percentage body fat, and fat-free body weight were obtained for 2,142 students in Grades 3, 7, and 11 (ages 9, 13, and 17 years), and the subjects were tested on 6 motor tasks. Multivariate analysis of variance indicated that performance decrements resulting from greater adiposity affects boys and girls equally. Furthermore, this male–female similarity in the degree that fatness handicaps performance holds constant across grades. Percentage-variance analyses revealed that childhood gender differences are substantially influenced by anthropometric variables, with approximately 50% of between-gender variance being accounted for by fatness alone. Boys exhibited progressively greater performance superiority from Grade 3 to Grade 11. However, for specific tasks, there was an age-related decrease in the degree to which anthropometric variables contributed to these gender differences. This prompted the conclusion that with advancing age gender differences may become increasingly more a function of environmental factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Physical self-concept and self-esteem mediate cross-sectional relations of physical activity and sport participation with depression symptoms among adolescent girls.

The authors tested whether physical self-concept and self-esteem would mediate cross-sectional relations of physical activity and sport participation with depression symptoms among 1,250 girls in 12th grade. There was a strong positive relation between global physical self-concept and self-esteem and a moderate inverse relation between self-esteem and depression symptoms. Physical activity and sport participation each had an indirect, positive relation with global physical self-concept that was independent of objective measures of cardiorespiratory fitness and body fatness. These correlational findings provide initial evidence suggesting that physical activity and sport participation might reduce depression risk among adolescent girls by unique, positive influences on physical self-concept that operate independently of fitness, body mass index, and perceptions of sports competence, body fat, and appearance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prognostic implications of p53 overexpression in cutaneous melanoma from sun-exposed and nonexposed sites

Reduced energy expenditure may predispose children to the development of obesity, but there are limited longitudinal studies to support this theory. We studied 75 white, preadolescent children over 4 y by taking annual measures of body composition and resting energy expenditure (by indirect calorimetry) and two annual measures of total energy expenditure and physical-activity-related energy expenditure (by doubly labeled water). Body composition of parents was assessed at the onset of the study with use of underwater weighing. The major outcome variable was the individual rate of change in fat mass (FM) adjusted for fat-free mass (FFM). The influence of sex, energy expenditure components, initial FM, and parental FM on the rate of change in FM was analyzed by hierarchical linear modeling and analysis of variance. The rate of change in absolute FM was 0.89 +/- 1.08 kg/y (range: -0.44 to 5.6 kg/y). The rate of change in FM adjusted for FFM was 0.08 +/- 0.64 kg/y (range: -1.45 to 2.22 kg/y) and was similar among children of two nonobese parents and children with one nonobese or one obese parent, but was significantly higher in children with two obese parents (0.61 +/- 0.87 kg/y). The major determinants of change in FM adjusted for FFM were sex (greater fat gain in girls), initial fatness, and parental fatness. None of the components of energy expenditure were inversely related to change in FM. The main predictors of change in FM relative to FFM during preadolescent growth are sex, initial fatness, and parental fatness, but not reduced energy expenditure.     

Pulmonary veins: magnetic resonance angiography anatomy

OBJECTIVES: This study was undertaken to investigate the relation between dietary fat composition and adiposity in adult men. SUBJECTS: A sample of 128 male subjects who participated in Phase 2 of the Québec Family Study. DESIGN: The association between adiposity and total dietary fat intake (TFI), saturated fat intake (SFA), monounsaturated fat intake (MUFA) and polyunsaturated fat intake (PUFA) was analyzed in the overall sample. A comparison of body fatness was also performed between consumers of high (4th quartile) and low amounts (1st quartile) of TFI, SFA, MUFA and PUFA. RESULTS: Significant positive correlations were found between the percentage of dietary energy as total fat and body fatness. Men in the upper quartile of TFI displayed significantly more adiposity than those in the lower quartile. Significant differences were also observed when quartiles were established using SFA and MUFA. However, higher intakes of PUFA had no statistical effects on adiposity. CONCLUSION: These results confirm the notion that high fat diets might lead over time to excess body fat deposition. SFA and MUFA intake also seem to be predictors of actual adiposity markers while high PUFA intake seems to exert no effect on these markers.     

High body fatness, but not low fat-free mass, predicts disability in older men and women: the Cardiovascular Health Study

Using data from the Cardiovascular Health Study, we studied the relation between body composition (fat mass and fat-free mass, assessed by bioelectrical impedance) and self-reported, mobility-related disability (difficulty walking or stair climbing) in 2714 women and 2095 men aged 65-100 y. In a cross-sectional analysis at baseline (1989-1990), disability was reported by 26.5% of the women and 16.9% of the men. A positive association was observed between fat mass and disability. The odds ratio for disability in the highest quintile of fat mass was 3.04 (95% CI: 2.18, 4.25) for women and 2.77 (95% CI: 1.82, 4.23) for men compared with those in the lowest quintile. Low fat-free mass was not associated with a higher prevalence of disability. In a longitudinal analysis among persons not reporting disability at baseline, 20.3% of the women and 14.8% of the men reported disability 3 y later. Fat mass at baseline was predictive of disability 3 y later, with odds ratios of 2.83 (95% CI: 1.80, 4.46) for women and 1.72 (95% CI: 1.03, 2.85) for men in the highest quintile of fat. The increased risk was not explained by age, physical activity, chronic disease, or other potential confounders. Low fat-free mass was not predictive of disability. The results showed that high body fatness is an independent predictor of mobility-related disability in older men and women. These findings suggest that high body fatness in old age should be avoided to decrease the risk of disability.     

Defining obesity in children by biological endpoint rather than population distribution

OBJECTIVE: To investigate the association of fatness in children with dyslipoproteinemia and high blood pressure, with the purpose of proposing standards for childhood obesity which are directly related to intermediate biological parameters that predict future disease. DESIGN: A cross-sectional study of a large, nationally representative sample of Australian schoolchildren. SUBJECTS: 1834 children aged 9 or 15 years, with skinfolds blood lipid measurements on 1144 and with skinfolds and blood pressure measurements on 1757. MEASUREMENTS: Skinfolds thicknesses measured at four locations (triceps, biceps, subscapular and suprailiac) using holtain calipers, percent body fat calculated from the sum of four skinfolds, Quetelet's index calculated from weight and height, waist and hip circumferences, plasma total cholesterol and triglycerides determined using a Technicon Autoanalyser II, high density lipoprotein cholesterol (HDLC) analysed following precipitation with heparin manganese, and systolic blood pressure (SBP) measured using a standard mercury sphygmomanometer. RESULTS: For 9 years old girls, 15 year old girls and 9 years old boys, dichotomising their HDLC and SBP measurements by percent body fat defined the two groups most homogeneous in terms of a measure of within-group variation. The cut-points in percent body fat were in the ranges 29-35% (girls) and 17-20% (boys). CONCLUSION: It is feasible to use the current biomedical status of individual children to define criteria for obesity. A cut-off point of 30% body mass as fat for girls and 20% for boys appears to be an appropriate standard.     

Relations of total and abdominal adiposity to muscle sympathetic nerve activity in healthy older males

OBJECTIVES: We recently reported that skeletal muscle sympathetic nerve activity (MSNA) is related to total body and abdominal fatness in a pooled population of young and older males. Both MSNA and adiposity increase with age. Thus, it is not clear if the relation between MSNA and adiposity exists among older adults and if the age-related increase in MSNA is explained by increases in adiposity. We therefore tested the hypotheses that: 1) among older men, those with higher total body fatness and abdominal adiposity have higher MSNA and 2) MSNA is not different in healthy young and older men with similar total body and/or abdominal fatness. DESIGN: Older healthy men (63 +/- 1 y) were separated into higher and lower groups of body fat (26.9 +/- 0.8%, n = 9 vs 21.3 +/- 1.1, n = 10; P < 0.0001) and waist circumference (96.4 +/- 3.5 cm, n = 8 vs 86.2 +/- 1.5, n = 8; P < 0.01). Younger controls (26 +/- 1 y) were then matched with those in the older-lower groups for %body fat (21 +/- 1.1%, n = 10) or waist circumference (86.2 +/- 0.8 cm, n = 10). MEASUREMENTS: Total body fat was determined by hydrodensitometry, abdominal adiposity by waist circumference and resting MSNA by microneurography. RESULTS: Among the older subjects those in the higher %body fat and waist circumference groups had higher (P < 0.02) MSNA (47 +/- 3 and 48 +/- 4 bursts/min, respectively) than those in the lower groups (37 +/- 2 and 38 +/- 3 bursts/min). MSNA was directly related to %body fat (r = 0.52, P = 0.03) and waist circumference (r = 0.64, P = 0.007) in the older groups. MSNA was greater (P < 0.001) in the older-lower groups than in the young controls matched for %body fat (23 +/- 2 bursts/min) or waist circumference (24 +/- 3 bursts/min). CONCLUSIONS: 1) among healthy older men, higher levels of total body and/or abdominal adiposity are associated with higher levels of MSNA and 2) the age-related elevation in MSNA is reduced but not abolished when differences in adiposity are eliminated.     

Assessment of adiposity in an Indian population: familial correlations

Familial correlations for five measures of adiposity were assessed using data from 473 nuclear families residing in the Chittoor district of Andhra Pradesh, India. Fat patterning, measured as the ratio of trunk to extremity subcutaneous fat, and the ratio of the subscapular to the sum of the subscapular and suprailiac skinfolds, and three measures of generalized fatness: body mass index, the sum of six skinfolds and the sum of three trunk skinfolds were analyzed. Maximum likelihood estimates of the familial correlations were obtained for each phenotype, after adjusting for the effects of (1) age within sex, and (2) current levels of energy intake and expenditure, and age within sex. Hypotheses regarding sex-specific, and generational differences in these correlations were assessed for each phenotype, under both adjustment schemes. The strength and pattern of the familial correlations for the three measures of generalized fatness were markedly influenced by the specific adjustments applied to the data. In contrast, the familial correlations for the fat patterning phenotypes were quite similar under the two adjustment schemes. Comparison of our results with previously published data indicates that the familial correlations for a subset of these adiposity measures may be heterogeneous across populations.     

Contribution of growth, fatness, and activity to weight disturbance after septohypothalamic cuts in adult hamsters.

Investigated the mechanism responsible for weight stability in 80 adult female golden hamsters by (a) transsecting the dorsoventrally oriented nerve pathways between the septal area and hypothalamus (SH cuts) and (b) partitioning the observed increases in the rate of weight gain into 3 contributory components: changes in somatic growth, in body fatness, and in energy expended as voluntary activity on horizontal disks. 60–70% of the weight increase after SH cuts was due to acquisition of lean body mass, and 30–40% consisted of excess body fat. After SH cuts, serum growth hormone and insulin concentrations were increased on Day 14, food intake was increased between Day 2 and Day 42, skeletal lengths were greater on Day 77, and voluntary activity levels were 84% lower on Days 10–45, relative to controls. It is concluded that dorsoventrally oriented nerve pathways in the septal area are involved in the control of growth, maintenance of body fat reserves, and voluntary activity. (51 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Inhibition of tumor growth and microvascular angiogenesis by the potent angiogenesis inhibitor, TNP-470, in rats

OBJECTIVE: To analyse the longitudinal relationships between body mass index (BMI)/sum of skinfolds (SSF) and biological and lifestyle risk factors for coronary heart disease (CHD). DESIGN: An observational longitudinal study; that is, the Amsterdam Growth and Health Study. SUBJECTS: 181 males and females, initially aged 13 y. Over a period of 15 y, six repeated measurements were carried out. MEASUREMENTS: BMI and SSF, biological CHD risk factors; that is, total cholesterol (TC), high density lipoprotein (HDL), TC:HDL ratio, systolic/diastolic blood pressure (SBP/DBP) and cardiopulmonary fitness (VO2-max) and lifestyle CHD risk factors (that is, daily physical activity, dietary parameters, smoking, and alcohol consumption). The longitudinal relationships were analysed by an autoregressive model, in which the value of the outcome variable at time-point t is not only related to the value of the predictor variable at t, but also to the value of the outcome variable at t-1. RESULTS: Both BMI and SSF were positively related to TC and the TC:HDL ratio. Only BMI was positively related to SBP and only SSF was negatively related to VO2-max. Physical activity was negatively related to SSF. None of the other lifestyle parameters were related to SSF and/or BMI. CONCLUSIONS: Both BMI and SSF were related to a high risk profile regarding CHD. Different relationships for SSF and BMI are found, because BMI not only reflects body fatness, but also lean body mass. Analyses with BMI as an indicator for body fatness should therefore be interpreted cautiously.     

Effects of gender, body composition, and menopause on plasma concentrations of leptin

Circulating concentrations of leptin ([leptin]) vary directly with body mass index and percentage body fat, and may thus constitute an afferent limb of a system regulating body fatness. We tested the hypotheses that: 1) Plasma [leptin] vary more directly with absolute fat mass than with fractional body fatness per se: and 2). The relationship between fat mass and [leptin] is significantly affected by gender and by menopausal status. [Leptin] in the post-absorptive state was examined in 67 subjects (26 male, 20 premenopausal female, 21 postmenopausal females; 43 never-obese, 24 obese) at usual body weight. Body composition was determined by hydrodensitometry, and [leptin] was determined by a double antibody ELISA assay. In male and pre-menopausal female subjects, subcutaneous adipose tissue aspirations were performed for determination of adipocyte volume by the osmium fixation method, and a 3 hour oral glucose tolerance tests was performed. At usual body weight, ([leptin]) was better correlated with absolute fat mass than with body mass index (BMI) or percentage body fat. BMI and % body fat did not account for any of the variance in [leptin] beyond that attributable to FM, per se. The regression equations relating FM to [leptin] did not differ significantly between obese and never-obese subjects. [Leptin] and fasting serum insulin concentrations were significantly correlated in males only. [Leptin] was significantly higher in pre- and post-menopausal females compared to males, even when [leptin] was corrected for differences in body composition (pre-menopausal females > post-menopausal females > males). While plasma [leptin], corrected for FM, declines significantly in women post-menopause, this decline is not sufficient to account for the striking sexual dimorphism in the relationship of leptin to fat mass. This sexual dimorphism is apparently also due, in part, to a suppressive effect of circulating androgens on [leptin].     

Serum leptin concentrations in Caucasian and African-American girls

Because African-American girls are heavier, taller, and mature earlier than Caucasian girls, we hypothesized that the serum leptin concentration differs between the two groups. Serum leptin concentrations were measured by immunoassay in 12-h fasted blood samples collected from 79 Caucasian and 57 African-American girls between 8 and 17 yr of age. Body composition was measured by dual-energy x-ray absorptiometry, sexual maturity by physical examination, and physical fitness by treadmill testing. Serum leptin concentrations were positively correlated (P < 0.01) with maturation, body fatness, and insulin and were higher (6.6 ng/mL, P < 0.01) in the African-American girls after adjusting for age. The difference remained significant (P < 0.01) but was reduced to 3.2 ng/mL after controlling for differences in maturation, fat mass, and physical fitness. The higher serum leptin levels might play an important role in the accelerated growth and sexual maturation of African-American girls.     

Urinary nickel excretion in populations living in the proximity of two russian nickel refineries: a Norwegian-Russian population-based study

In addition to being associated with termination of reproductive life in women, the menopause coincides with an increase in several comorbidities including cardiovascular disease. This increase in the prevalence of cardiovascular disease in the postmenopausal years has been partially attributed to adverse effects of estrogen deficiency on plasma lipid-lipoprotein levels and on the cardiovascular system, although other factors are contributing. Central body fatness and insulin resistance are components of a cluster of metabolic abnormalities which also increases the risk of cardiovascular disease. This review summarizes studies that have examined the effects of the menopause transition and of estrogen-replacement therapy on central body fatness and insulin resistance. Review of cross-sectional studies suggests that the menopause transition is associated with an increase in abdominal and visceral adipose tissue accumulation, as measured either with dual X-ray absorptiometry or computed tomography. These results appear to be independent of the aging process and total body fatness. In general, cross-sectional studies using circumference measurements did not find any significant effect of the menopause. Longitudinal studies also support that accumulation of central body fatness accelerates with menopause. The effects of the menopause on insulin resistance appear to be moderate, if any, although available studies are clearly insufficient to draw firm conclusions. The majority of interventional studies support the notion that hormone-replacement therapy attenuates the accumulation of central fat in postmenopausal women, compared with control or placebo-treated women. Retrospective comparisons of hormone users and nonusers also support a protective effect of hormone replacement on fat distribution. Moderate effects of estrogen therapy were found on insulin resistance in postmenopausal women, although long-term, controlled trials using accurate measurements of insulin sensitivity are lacking. Treatment with progestins exerts moderate deleterious effects on insulin sensitivity, which may be attributable to the partial androgenicity of progestins used. It is concluded that part of the increased incidence of cardiovascular disease in postmenopausal women may be attributable to increased central body fatness. Therapies aiming at preventing these changes in fat distribution such as hormone-replacement therapy, diet or exercise are likely to provide long-term cardiovascular and metabolic benefits for women's health.     

Interpersonal facilitation and job dedication as separate facets of contextual performance.

This study attempts to refine the construct of contextual performance by dividing it into 2 narrower constructs, interpersonal facilitation and job dedication. Supervisors rated 975 U.S. Air Force mechanics on at least 1 of 4 aspects of job performance (different supervisors rated each aspect of performance), and 515 of these mechanics also completed self-report individual difference measures. Correlations between performance ratings and individual difference variables support distinguishing task performance from interpersonal facilitation but not from job dedication. Thus this study suggests the need to redefine task performance to include motivational elements of job dedication. Then task performance would include task proficiency and motivation to perform one's own tasks effectively, and contextual performance would include interpersonal skills, the motivation to maintain good working relationships and help others perform their tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Central markers of body fat distribution are important predictors of plasma lipids in elderly men and women

We determined the contribution of body fat distribution, peak VO2, fat mass, and dietary intake to variation in plasma lipids in elderly individuals. Volunteers were a healthy cohort of older Caucasian women (n = 75, mean age +/- SD, 72 +/- 5 years) and older men (n = 101, 72 +/- 5 years). We determined fat mass from underwater weighing, fat patterning from waist circumference, as well as peripheral and truncal skinfolds, exercise capacity from peak VO2, and dietary intake from three-day food diaries. Plasma lipid levels were measured in the fasting state and included total cholesterol, high density lipoprotein (HDL-C), low density lipoprotein (LDL-C), and fasting triglycerides. Older women weighted less than older men, but had higher fat mass, truncal, and peripheral skinfolds. Waist circumference and peak VO2 were lower in older women than older men. Older women had higher total cholesterol (217 +/- 31 vs. 197 +/- 30; p < 0.01), HDL-C (54 +/- 12 vs. 49 +/- 14; p < 0.05), and LDL-C (133 +/- 26 vs. 121 +/- 27; p < 0.01) when compared with older men. No gender differences were noted in fasting triglycerides. Truncal skinfolds were the best predictor of plasma lipids in older men, accounting for between 9% and 30% (r2) of the variation in plasma lipids. Similarly, in older women, central markers of fatness (i.e., waist circumference and truncal skinfolds) were the best predictors of plasma lipids (r2 = 3% to 24%). Total fat mass, peak VO2 and dietary intake were not independent predictors of plasma lipids in older men and women. Indices of central body fatness, rather than total fat mass, peak VO2 or dietary intake are stronger predictors of plasma lipids in healthy older men and women.     

Prenatal exposure to alcohol, caffeine, tobacco, and aspirin: Effects on fine and gross motor performance in 4-year-old children.

Fine and gross motor performance in 4-year-old children was examined in relation to prenatal exposure to alcohol, caffeine, tobacco, and aspirin in a longitudinal prospective population-based study. Multiple regression analyses of data from 449 children indicated statistically significant relationships between moderate levels of prenatal alcohol exposure and increased errors, increased latency, and increased total time on the Wisconsin Fine Motor Steadiness Battery and poorer balance on the Gross Motor Scale, even after adjustment for relevant covariates. Most of these alcohol-related motor findings were linear, suggesting no safe level of exposure. Alcohol scores from the period prior to pregnancy recognition were the most predictive of decrements in motor performance. Although moderate prenatal alcohol exposure was also related to lower IQ scores in this same cohort, the motor effects were independent of IQ. Some relationships with aspirin and caffeine were also found, but they were difficult to interpret. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Motor proficiency and attentional-task performance by psychotic patients.

Investigated the relation between motor proficiency and performance on the Continuous Performance Test (CPT) among 24 schizophrenic inpatients (mean age 34 yrs) and 24 inpatients with affective disorders (mean age 33.8 yrs). Ss completed the Bruininks-Oseretsky Test of Motor Proficiency. A correlational analysis revealed that motor subtest scores were significantly related to CPT performance indexes for all Ss; decreased motor proficiency was related to more CPT errors and longer RTs. Results suggest that CPT performance is related to motoric factors and that deficits on this task may be partially attributable to poor motor abilities. (30 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)