Reliability and variability of bioimpedance measures in normal adults: effects of age, gender, and body mass

This study aimed to analyze the reliability and evaluate the causes of variability of bioimpedance parameters. Direct measures were analyzed because they are not affected by inappropriate prediction models. Resistance (R), reactance (Xc), and phase angle (PA) were determined at three fixed frequencies (5, 50, and 100 kHz) in 653 normal Germans (244 males and 409 females), aged 20-90 years, using a phase-sensitive whole-body tetrapolar bioimpedance analyzer (BIA 2000-M, Data Input, Germany). From these values, six bioimpedance ratios were calculated (R(5)/R(50), R(5)/R(100), Xc(5)/Xc(50), Xc(5)/Xc(100), PA(5)/PA(50), and PA(5)/PA(100)). Reliability of duplicate measurements, as determined by technical error, is high. ANOVA for repeated measurements yields a significant frequency main effect (within-subjects factor) and significant effects of age and gender (between-subject factors) on variation of resistance, reactance, and phase angle. Multiple regression analyses indicate independent effects of age, gender, and body mass index on variability of resistance, reactance, and phase angle at the three frequencies. Gender primarily influences variation in resistance (smaller values in males), whereas age mainly affects variations in reactance and phase angle (smaller values in older adults). Obesity is associated with smaller resistance (at all frequencies) and smaller reactance (high frequencies), but larger phase-angle values (low frequency). The study shows that variability of direct bioimpedance measures depends on age, gender, and body mass characteristics of the study population. The potential benefit for using both low and high frequencies in R measures is to differentiate between extra- and intracellular fluid spaces, which may be altered during human growth and aging.     

Diet quality of middle age and older women from Primorsko-Goranska County evaluated by healthy eating index and association with body mass index

Accorded dietary habits provide adequate nutrient intakes, especially important for quality aging. Adequate nutrition for older persons has vital influence on maintaining good health and social functioning. Therefore, using simple tool for evaluation of diet of older population in relation to overweight and obesity is of public health importance. Among many factor that influence quality of aging has obesity, where in Croatia the prevalence of obesity is greater in older women than men. Our aim was to evaluate diet quality of middle age and older women from Primorsko-Goranska County by Healthy Eating Index (HEI) and to see the association of HEI to overweight and obesity. Diet quality of 124 women with average age 59.91 +/- 5.31 years was graded with 10 component HEI score, ranging from 0 to 100, where HEI score less than 51 implies "poor" diet. Overweight and obesity was classified according to WHO classification. The majority of women had diet that "needs improvement" (66.1%), and only 3.2% had "good" diet. Older women had better HEI score than middle-aged women, while overweight was statistically significant positively related to better HEI score (P = 0.26, p = 0.048). Older women better scored for meat, dairy, cholesterol and dietary variety. "Poor" diet mostly had women with normal weight and middle-aged. Age did not influenced overall HEI score, neither its components. Obese women had lower achievements for almost all recommended HEI components. Women having "poor" diet quality could raise a chance for overweight and obesity for almost two times ([OR] = 1.67, 95% [CI] = 1.072-2.59, p = 0.023; [OR] = 1.51, 95% [CI] = 1.08-2.10, p = 0.015, respectively). The provided results showed that with age, women tended to have better diet. These could be because of that with aging are higher disease incidences that essentially need diet improvements; so older women tended to improve their diet to reduce disease discomforts. Being obese influenced the diet quality of our sample of women, therefore, for quality aging, the importance of public health nutrition programs are strongly needed. HEI score is a good assessment for diet quality, but further investigation of influence on other sociodemographic and health characteristics is required.     

Variation in body mass index among Polish adults: effects of sex, age, birth cohort, and social class

Remains of 15 hominids were recovered within a Mousterian archaeological context in the cave of Qafzeh, Israel. Dated to ca. 95 kyr BP, this skeletal material has been crucial for understanding biological, chronological, and cultural aspects of anatomically modern ancient Homo sapiens. The high proportion of children (N = 8) in Qafzeh Cave is unique among Middle Palaeolithic sites and encourages the search for skeletal evidence of disease and trauma. We report on the case of one child, Qafzeh 12, ca. 3 years old (according to modern human reference standards), who manifests some outstanding skeletal abnormalities that indicate hydrocephalus.     

Growth hormone secretion in primary adrenal Cushing's syndrome is disorderly and inversely correlated with body mass index

To evaluate the impact on the somatotropic axis of endogenous cortisol excess in the absence of primary pituitary disease, we investigated spontaneous 24-h growth hormone (GH) secretion in 12 adult patients with ACTH-independent hypercortisolism. Plasma GH concentration profiles (10-min samples) were analyzed by deconvolution to reconstruct secretion and approximate entropy to quantitate orderliness of the release process. Comparisons were made with a body mass index (BMI)-, age-, and gender-matched control group and an age- and gender-matched lean control group. GH secretion rates did not differ from BMI-matched controls but were twofold lower compared with lean subjects, mainly due to a 2.5-fold attenuation of the mean secretory burst mass (P = 0.001). In hypercortisolemic patients, GH secretion was negatively correlated with BMI (R = -0.55, P = 0.005) but not cortisol secretion. Total serum IGF-I concentrations were similar in the three groups. Approximate entropy (ApEn) was increased in patients with Cushing's syndrome compared with both control groups (vs. BMI-matched, P = 0.04; vs. lean, P = 0.001), denoting more irregular GH secretion patterns. ApEn in patients correlated directly with cortisol secretion (R = 0.77, P = 0.003). Synchrony between cortisol and GH concentration series was analyzed by cross-correlation, cross-ApEn, and copulsatility analyses. Patients showed loss of pattern synchrony compared with BMI-matched controls, but copulsatility was unchanged. We conclude that hyposomatotropism in primary adrenal hypercortisolism is only partly explained (approximately 30%) by increased body weight and that increased GH secretory irregularity and loss of synchrony suggest altered coordinate regulation of GH release.     

The estimation of body mass index and physical attractiveness is dependent on the observer's own body mass index

A disturbance in the evaluation of personal body mass and shape is a key feature of both anorexia and bulimia nervosa. However, it is uncertain whether overestimation is a causal factor in the development of these eating disorders or is merely a secondary effect of having a low body mass. Moreover, does this overestimation extend to the perception of other people''s bodies? Since body mass is an important factor in the perception of physical attractiveness, we wanted to determine whether this putative overestimation of self body mass extended to include the perceived attractiveness of others. We asked 204 female observers (31 anorexic, 30 bulimic and 143 control) to estimate the body mass and rate the attractiveness of a set of 25 photographic images showing people of varying body mass index (BMI). BMI is a measure of weight scaled for height (kg m(- 2)). The observers also estimated their own BMI. Anorexic and bulimic observers systematically overestimated the body mass of both their own and other people''s bodies, relative to controls, and they rated a significantly lower body mass to be optimally attractive. When the degree of overestimation is plotted against the BMI of the observer there is a strong correlation. Taken across all our observers, as the BMI of the observer declines, the overestimation of body mass increases. One possible explanation for this result is that the overestimation is a secondary effect caused by weight loss. Moreover, if the degree of body mass overestimation is taken into account, then there are no significant differences in the perceptions of attractiveness between anorexic and bulimic observers and control observers. Our results suggest a significant perceptual overestimation of BMI that is based on the observer''s own BMI and not correlated with cognitive factors, and suggests that this overestimation in eating-disordered patients must be addressed directly in treatment regimes.     

Chemokines and their association with body mass index among healthy Saudis

Obesity is a chronic disorder that is associated with body mass index (BMI) of greater or equal to 30 kg/m². The prevalence of obesity in the Kingdom of Saudi Arabia (KSA) is increasing at an alarming rate and is expected to reach 41% in men and up to 78% in women by 2022. Since chemokines are associated with involuntary weight loss, the objective of this study was to elucidate their association with BMI among Saudis. A questionnaire was used to collect information about diet, health conditions, and demographics from 15 men and 16 women who participated in the study. BMI was calculated based on clinical measurements and participants were classified according to their BMI category as: normal, underweight, overweight, or obese. Serum samples were collected for a multiplex assay using the Human Chemokine Magnetic 30-plex panel. The serum concentration of either the monokine induced by gamma interferon (MIG) or the CXC-motif chemokine ligand 9 (CXCL-9) was significantly increased in obese men (P = 0.0194) and women (P = 0.043) as compared to underweight men and women, respectively. However, the serum levels of other chemokines were not significantly different among the groups. We found that MIG levels are differentially regulated in serum, based on individuals’ BMI.     

Overweight in urban schoolchildren assessed by body mass index and body fat mass in Dalian, China

In order to assess overweight in urban schoolchildren (298 boys and 298 girls) aged 9-16 years in Dalian, China, their body height, weight, skinfolds at triceps, biceps, subscapular and suprailiac, and body circumferences of mid-upper arm, waist and hip were measured. The results showed that the prevalence of overweight, based on the United States Centers for Disease Control 2000 reference values using body mass index (BMI), was 22.9% in boys and 10.4% in girls, which was higher than that of indicated in Chinese national surveys of recent decades. More boys were overweight than girls due to excessive increase in body fat, although the prevalence of overweight in girls prevalence increased from 13 years. Discussion here focuses on the effects of behavioral patterns on overweight in Dalian schoolchildren, paying attention to gender difference.     

Body mass index related electrocardiographic findings in healthy young individuals with a normal body mass index

Introduction

An increased body mass index (BMI) (>25 kg/m²) is associated with a wide range of electrocardiographic changes. However, the association between electrocardiographic changes and BMI in healthy young individuals with a normal BMI (18.5–25 kg/m²) is unknown. The aim of this study was to evaluate the association between BMI and electrocardiographic parameters.

Methods

Data from 1,290 volunteers aged 18 to 30 years collected at our centre were analysed. Only subjects considered healthy by a physician after review of collected data with a normal BMI and in sinus rhythm were included in the analysis. Subjects with a normal BMI (18.5–25 kg/m²) were divided into BMI quartiles analysis and a backward multivariate regression analysis with a normal BMI as a continuous variable was performed.

Results

Mean age was 22.7 ± 3.0 years, mean BMI was 22.0, and 73.4% were male. There were significant differences between the BMI quartiles in terms of maximum P-wave duration, P-wave balance, total P-wave area in lead V1, PR-interval duration, and heart axis. In the multivariate model maximum P-wave duration (standardised coefficient (SC) = +0.112, P < 0.001), P-wave balance in lead V1 (SC = +0.072, P < 0.001), heart axis (SC = −0.164, P < 0.001), and Sokolow-Lyon voltage (SC = −0.097, P < 0.001) were independently associated with BMI.

Conclusion

Increased BMI was related with discrete electrocardiographic alterations including an increased P-wave duration, increased P-wave balance, a leftward shift of the heart axis, and decreased Sokolow-Lyon voltage on a standard twelve lead electrocardiogram in healthy young individuals with a normal BMI.

     

The impact of age, sex, body mass index and menstrual cycle phase on gastric myoelectrical activity characteristics in a healthy Croatian population

The aim of the study was to determine the impact of demographic and anthropometric parameters on the gastric myoelectrical activity characteristics in a healthy Croatian population. The influence of age, sex, body mass index (BMI) and menstrual cycle phase on the gastric myoelectrical activity characteristics was assessed. The study included 120 healthy subjects of both sexes (60 male and 60 female), divided into four age groups (18-35, 36-50, 51-65 and > 65 years) and three BMI groups (BMI < 25, 25-30 and > 30). Female subjects of reproductive age were divided into three groups according to menstrual cycle phase (day 1-3, day 4-8 and day 9-20 of menstruation). All study subjects underwent percutaneous electrogastrography (EGG) for 60 min before and 60 min after a test meal. The following parameters of the gastric myoelectrical activity were observed: dominant frequency (DF); dominant frequency within normal range (DFNR, %); coefficient of variation for dominant frequency (CVDF); dominant strength (DS. mV); postprandial increase intensity in dominant strength (PPIIDS, %); bradygastria (BG, c/min, %); tachygastria (TG, c/min, %); and arrhythmia (AR). Age was found to influence preprandial but not postprandial DFNR, CVDF and AR. Sex influenced preprandial DF, CVDF, DS and BG, and postprandial DF, CVDF, PPIIDS and TG. BMI exerted an impact on preprandial TG and AR, and postprandial DF, CVDF and AR. The phase of menstrual cycle influenced DF in preprandial period and none of EGG parameters in postprandial period.     

Relationship between body mass index and gray matter volume in 1,428 healthy individuals

Objective: To investigate any correlation between BMI and brain gray matter volume, we analyzed 1,428 healthy Japanese subjects by applying volumetric analysis and voxel‐based morphometry (VBM) using brain magnetic resonance (MR) imaging, which enables a global analysis of brain structure without a priori identification of a region of interest. Methods and Procedures: We collected brain MR images from 690 men and 738 women, and their height, weight, and other clinical information. The collected images were automatically normalized into a common standard space for an objective assessment of neuroanatomical correlations in volumetric analysis and VBM with BMI. Results: Volumetric analysis revealed a significant negative correlation in men (P < 0.001, adjusting for age, lifetime alcohol intake, history of hypertension, and diabetes mellitus), although not in women, between BMI and the gray matter ratio, which represents the percentage of gray matter volume in the intracranial volume. VBM revealed that, in men, the regional gray matter volume of the bilateral medial temporal lobes, anterior lobe of the cerebellum, occipital lobe, frontal lobe, precuneus, and midbrain showed significant negative correlations with BMI, while those of the bilateral inferior frontal gyri, posterior lobe of the cerebellum, frontal lobes, temporal lobes, thalami, and caudate heads showed significant positive correlations with BMI. Discussion: Global loss and regional alterations in gray matter volume occur in obese male subjects, suggesting that male subjects with a high BMI are at greater risk for future declines in cognition or other brain functions.     

Vitamin D status and its relation to age and body mass index

BACKGROUND/AIMS: While numerous studies have examined 25(OH)-vitamin D(3) (25-D) concentrations and their relation to parathyroid hormone (PTH) levels there is only limited information on the interrelation between 25-D, 1,25(OH)(2)-vitamin D(3) (1,25-D) and PTH. It was the aim of this study to assess the vitamin D endocrine system and its relation to age and body mass index (BMI). METHODS: This cross-sectional study comprised a convenience sample of 483 adults which attended the endocrinology outpatient service of a university hospital in the years 2002-2004. RESULTS: The mean concentrations of 25-D, 1,25-D, calcium and PTH were 21.0 +/- 10.6 ng/ml, 47.9 +/- 21.7 pg/ml, 9.48 +/- 0.48 mg/dl and 51.0 +/- 27.2 pg/ml, respectively. 25-D was related (p < 0.01) to BMI, age, PTH and 1,25-D. After correction for 25-D, we found no relation between BMI and 1,25-D. PTH was related (p < 0.01) to serum calcium, BMI, age and 1,25-D (p = 0015). There was a seasonal variation in both, 25-D and 1,25-D serum concentrations: 25-D levels were lowest in January and increased until July while the nadir and zenith of 1,25-D were found in April and October, respectively. CONCLUSION: Since BMI was negatively related to 25-D the prevalence of 25-D deficiency (<8.8 ng/ml) increased from 8.8% in subjects with BMI <30 kg/m(2) to 15.0% in subjects with BMI >30 kg/m(2). BMI, age and season should be taken into account when assessing a patients vitamin D status and more aggressive vitamin D supplementation should be considered for obese subjects.     

Association between body mass index and muscularity in healthy older Japanese women and men

Background

Body mass index (BMI), expressed as the ratio of body mass to height squared (kg/m²), involves not only fat but also lean mass. The present study aimed to clarify how BMI is associated with total muscle mass (TMM) in older Japanese women and men.

Findings

Using a B-mode ultrasound apparatus, muscle thickness was measured at nine sites (forearm, upper arm anterior and posterior, thigh anterior and posterior, lower leg anterior and posterior, abdomen, and subscapular) for 346 women (BMI 16.40 to 33.11 kg/m²) and 286 men (BMI 16.86 to 31.18 kg/m²) aged 60.0 to 79.5 yrs. TMM was estimated using the product of the sum of the muscle thicknesses at the nine sites with height as an independent variable. For both sexes, the estimated TMM relative to height squared was significantly correlated with BMI (r = 0.688, P<0.0001 for women; r = 0.696, P<0.0001 for men), but the percentage of the estimated TMM in body mass was not.

Conclusion

These results indicate that, for older Japanese women and men, BMI is a simple and convenient index for assessing total muscularity.     

Influence of sex,age, body mass index,and smoking on alcohol intake and mortality.

OBJECTIVE--To examine the association between self reported alcohol intake and subsequent mortality from all causes and if the effect of alcohol intake on the risk of death is modified by sex, age, body mass index, and smoking. DESIGN--Prospective population study with baseline assessment of alcohol and tobacco consumption and body mass index, and 10-12 years'' follow up of mortality. SETTING--Copenhagen city heart study, Denmark. SUBJECTS--7234 women and 6051 men aged 30-79 years. MAIN OUTCOME MEASURE--Number and time of deaths from 1976 to 1988. RESULTS--A total of 2229 people died, 1398 being men. A U shaped curve described the relation between alcohol intake and mortality. The lowest risk was observed at one to six alcoholic beverages a week (relative risk set at 1). Abstainers had a relative risk of 1.37 (95% confidence interval 1.20 to 1.56) whereas those drinking more than 70 beverages a week had a relative risk of 2.29 (1.75 to 3.00). Among the drinkers, the risk was significantly increased only among those drinking more than 42 beverages a week. Sex, age, body mass index, and smoking did not significantly modify the risk function. The risk among heavy drinkers was slightly reduced when smoking was controlled for. The risk function was similar in the first and second period of six years of observation. CONCLUSION--Alcohol intake showed a U shaped relation to mortality with the nadir at one to six beverages a week. The risk function was not modified by sex, age, body mass index, or smoking and remained stable over 12 years.     

A statistical human rib cage geometry model accounting for variations by age,sex, stature and body mass index

In this study, we developed a statistical rib cage geometry model accounting for variations by age, sex, stature and body mass index (BMI). Thorax CT scans were obtained from 89 subjects approximately evenly distributed among 8 age groups and both sexes. Threshold-based CT image segmentation was performed to extract the rib geometries, and a total of 464 landmarks on the left side of each subject?s ribcage were collected to describe the size and shape of the rib cage as well as the cross-sectional geometry of each rib. Principal component analysis and multivariate regression analysis were conducted to predict rib cage geometry as a function of age, sex, stature, and BMI, all of which showed strong effects on rib cage geometry. Except for BMI, all parameters also showed significant effects on rib cross-sectional area using a linear mixed model. This statistical rib cage geometry model can serve as a geometric basis for developing a parametric human thorax finite element model for quantifying effects from different human attributes on thoracic injury risks.