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The influence of spiritual factors on the ability of African-American elders to carry out instrumental activities of daily living (IADL) independent of age, gender, education, and self-rated health is explored using the religion-health explanatory model in a cross-sectional sample of 96 African-American community dwelling adults 62 to 93 years of age. The Reed spiritual perspective (SPS) and self-transcendence (STS) scales are used to study spiritual factors (Reed, 1991). The typical respondent was 75 years of age, female, widowed with 10.4 years of education. Self-rated health and age are strongly related to IADL in models that include the other variables ( R2 = 0.41, p < 0.01). Those who are younger and those who self-report better health have higher IADL scores than those without these characteristics. Spiritual factors are significantly related to IADL in a model that includes an interaction of STS with education ( R2 = 0.50). Among the least educated, STS is associated with higher scores of IADL. Addition of the interaction to the model resulted in a significant positive association of both STS and education with IADL. SPS was unrelated to IADL. Caregivers concerned with functional ability may want to consider interventions based on increasing a sense of self-transcendence, and to consider educational level as a potential moderator of this relationship. Criticism of the religion-health literature has suggested that putative health effects of religion may be exaggerated, because of failure to take confounding variables into account (Sloan, Bagiella, & Powell, 1999). However, this study and a recent survey by Musick, House, and Williams (2004) are evidence that it is just as likely that health benefits of religion would be hidden by confounders as that they would be exaggerated by them.

Background: Adolescence is characterized by profound changes in physical, psychological, and social functioning thought to be accompanied by intense and varying moods.Purpose: Within a psychophysiological framework, this study examined the prevalence of 12 self-reported mood states of adolescents; investigated associations between specific mood states and ambulatory blood pressure readings; and explored effects of interactions among moods, gender, ethnic group, and maturation on ambulatory blood pressures.Methods: The sample included 371 African American, European American, and Hispanic American adolescents 11 to 16 years old. Systolic (SBP) and diastolic (DBP) blood pressures were measured every 30 min with an ambulatory monitor and were synchronized with electronic activity monitoring and moods self-recorded during waking hours in a checklist diary.Results: Moods differed significantly by gender, ethnic group, and maturation. Controlling for height, maturation, gender, ethnic group, mother’s education, position, location, activity, other moods, and interactions of moods with other variables in a multilevel, random coefficients regression model, both positive and negative mood states were associated with higher levels of SBP and DBP; being relaxed or bored, or having a feeling of accomplishing things were associated with lower SBP and DBP. There were significant interaction effects of moods with physical maturity, gender, and ethnic group on ambulatory SBP and DBP.Conclusions: Further study of the modifying effects of gender, ethnic group, and stage of development on reports of moods, and their associations with cardiovascular responses is recommended.

To compare the utility of 10 commonly used body composition indicators (BCIs) in relation to demographic characteristics and cardiovascular risk factors.A cross-sectional, school sample was studied.Three hundred and eighty-four Black, White and Hispanic adolescents 11-16 years of age from Houston, Texas, USA (Heartfelt Study) were studied.BCIs include impedance and skinfold estimates of fat-free mass (FFM); fat mass (FM) and per cent body fat (PBF); resistance mass index (RMI); body mass index (BMI); and waist and abdomen circumferences. The cardiovascular risk factors (blood pressures/heart rates) are summarized by factor analysis. Sexual maturity was clinically assessed.Two distinct classes of BCIs emerged with respect to demographic influences: (1) RMI, impedance and skinfold estimators, for which sexual dimorphism is evident, and (2) BMI and circumferences, for which it is not. All BCIs were strongly related to general (systolic) blood pressure, but only body fat variables were related to heart rates. Skinfold-derived FM, PBF and mid-body circumferences were the variables most strongly related to cardiovascular risk factors.RMI, impedance or skinfold estimators are necessary for research requiring an accurate description of body composition changes during adolescence and for assessing the role of lean and fat tissue in disease aetiology. A 2-skinfold method is just as effective as the more complicated impedance. Mid-body circumferences are closely related to blood pressures and heart rates, suggesting their importance as indicators of abdominal fat in adolescents.

Obesity has reached epidemic proportions in the U.S. and more developed countries, particularly so among adolescents. A substantial impact on public health could be achieved if other factors causing obesity besides the conventional ones of diet and physical activity could be identified and acted upon. The present study investigates whether there is a link between low sleep quality and obesity in a tri-ethnic, cross-sectional sample (n = 383) of male and female adolescents ages 11-16 years old (Heartfelt Study). Sleep quality was expressed as two variables, total sleep time and sleep disturbance time obtained by 24-hour wrist actigraphy. Percent body fat and body mass index (BMI) were used together to define obesity. The potential influence of demographic and behavioral confounders were considered in models that described the relation of sleep to obesity occurrence. Obese adolescents experienced less sleep than nonobese adolescents (P < 0.01). For each hour of lost sleep, the odds of obesity increased by 80%. Sleep disturbance was not directly related to obesity in the sample, but influenced physical activity level (P < 0.01). Daytime physical activity diminished by 3% for every hour increase in sleep disturbance. The above observations were independent of potential confounding variables. Inadequate and poor sleep quality in adolescents may be important factors to consider in the prevention of childhood obesity.

To compare growth patterns of obesity indices derived from body composition and anthropometric measures, the authors analyzed data from Project HeartBeat!, a longitudinal study of cardiovascular disease risk factors in childhood and adolescence. A total of 678 children initially aged 8, 11, and 14 years in The Woodlands and Conroe, Texas, were enrolled and followed with 4-monthly examinations between October 1991 and August 1995. Trajectories of change from age 8 years to age 18 years were estimated for body mass index, percent body fat, abdominal circumference, the sum of two skinfolds, and the sum of six skinfolds. All indices varied importantly with age. Percent body fat, sum of two skinfolds, and sum of six skinfolds shared similar growth patterns, with strong divergence between males and females. Males' body fat decreased with age and females' increased or remained nearly constant with age. In contrast, both body mass index and abdominal circumference increased monotonically with age in both sexes, exhibiting little sex difference as children reached late adolescence. Sex differences were more striking among Blacks than among non-Blacks. The authors conclude that growth patterns of adiposity differ according to the measure chosen. Furthermore, changes in different obesity indices may not relate in the same way to changes in blood pressure or blood lipid concentrations.

OBJECTIVE: To investigate whether within-individual variation is a factor in the generally reported poor tracking of central body fat distribution (CBFD) during development and whether two measurements of CBFD during each measurement occasion would improve the estimate of tracking over time. METHODS: A longitudinal study compared the results of two measurements of body fat (BF) and CBFD during each measurement occasion to the results of one measurement of BF and CBFD during each occasion every 4 months over 1–3 y. A total of 345 boys and 333 girls in three age cohorts of 8, 11 and 14 y at baseline were examined. BF variables were: body mass index (BMI); fat mass and percentage body fat from bioelectrical impedance; two skinfold sums; and abdominal circumference. CBFD variables were: waist/hip and waist/thigh ratios; conicity; and log upper-lower skinfold ratio. RESULTS: Three-year tracking of BF varied from 0.79 to 0.90 for one- and from 0.81 to 0.93 for two-occasion measurements showing no apparent sex- or cohort-effects. Three-year tracking of CBFD was lower than that of BF (0.68–0.75), but improved significantly with two-occasion measurements (0.75–0.82). CONCLUSIONS: Within-individual variation is a significant factor in reported low tracking of CBFD in childhood. Estimates of tracking currently in the literature may underestimate the predictive value of CBFD, possibly because this research has used one-occasion measurement. The increased use of two-occasion measurement should significantly improve the tracking of CBFD during development and provide a more realistic understanding of its predictive value.

This study investigates sexual maturity as a predictor of resting blood pressures independent of other known predictors, in 179 boys and 204 girls 11-16 years of age from the Heartfelt Study. The sample included youth of African (n = 140), Mexican (n = 117), and European and “other” (n = 126) backgrounds. Sexual maturity was assessed during clinical examination of three standard indicators for each sex. Systolic and diastolic blood pressures were higher in children of maturity stages IV and V, compared to stages I–III, in each gender/ethnic group (P < 0.01 in almost all groups). Boys and girls advanced in sexual maturity for their age group, had significantly higher systolic blood pressures (but not diastolic) than the less advanced in linear models that included height, body mass index (BMI), ethnicity, and age as co-predictors. Diastolic blood pressures were predicted by height in boys and by age and the BMI in girls. This analysis, using a very conservative approach, suggests that sexual maturity provides important and independent information on systolic blood pressure in adolescents. Further investigation of its role in 24-hr blood pressures and in blood pressures taken during physical and emotional stress, is recommended. Am. J. Hum. Biol. 13:227–234, 2001. © 2001 Wiley-Liss, Inc.

Project HeartBeat! is a four year mixed-longitudinal study of the development of cardiovascular risk factors in White and African American children who at baseline comprised three age cohorts 8, 11, and 14 years. This paper focuses on the anthropometric variables which were chosen to reflect body fat and fat-free mass. Selected anthropometric dimensions are compared with those of samples from the combined National Health and Nutrition Examination Surveys I and II to explore the similarities of the samples in terms of central tendencies and variances. The measurements were then explored in terms of their ability to estimate the two compartment model of body composition: fat-free mass (FFM) and body fat (BF) from bioelectrical impedance (BIA). Project HeartBeat! children are slightly larger than NHANES children and have variances that are generally comparable to the national surveys. Over seven percent (7.7%) of children were overweight (BMI) and 25% had 'mild obesity' by %BF. Three different factor analytic methods (incomplete principal components, alpha and maximum likelihood) produced two latent variables from 17 anthropometric dimensions which together accounted for 76-83% of the variation: (1) A body mass factor (F1) which was weighted highly on six circumferences, weight and six skinfolds, and (2) a linear growth factor (F2) which was strongly associated with height, arm length, and sitting height. Triceps, subscapular and midaxillary skinfolds were consistently highly loaded on the body mass factor and their sum was highly correlated to %BF and fat mass (0.90-0.99). This suggests that this sum could be used to estimate fatness in children in studies where the BIA or other body composition techniques are unavailable. FFM and %BF were predicted from the anthropometric factors. Both factors contributed to the estimate of FFM (R(2) = 0.81-0.93), although F2 contributed proportionately more. The 'body mass' factor (F1) was the main predictor of %BF (R(2) = 0.86-0.93), though at some ages the linear factor (F2) was significantly and negatively related to %BF. This set of anthropometric dimensions, taken for the purpose of estimating body composition and summarized as two latent vectors by factor analysis, strongly reflects body fat and FFM in children and adolescents. Am. J. Hum. Biol. 11:69-78, 1999. Copyright 1999 Wiley-Liss, Inc.

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) (p0.01). 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 (p0.01). 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.

Distinctions between male and female adult patterns of cardiovascular disease are well established. Although risk for cardiovascular disease begins early in life, little research has been focused on the beginning of gender difference patterns. This pilot study examined blood pressure reactivity, gender, and biologic maturity in adolescents talking about angry life circumstances and the usual progression of their day. Systolic and diastolic blood pressure increased during talking, and the addition of biologic maturity to the analysis distinguished males from females. Males had higher systolic blood pressures than did females throughout the protocol, and, generally, mature subjects had higher systolic and diastolic blood pressures than did less mature subjects. These pilot data confirm the effects of talking on blood pressure. The data suggest that biologic maturity enhances understanding of gender differences in adolescent blood pressure reactivity and continued study of the gender-blood pressure reactivity distinctions in adolescents may further understanding of adult patterns of gender differences in cardiovascular disease.

The aim of this study was to determine whether subcutaneous fatness and fat distribution differ on the basis of feeding practice and sex during the first 6 months of life. Longitudinal principal components analysis (PCA) was done on skinfolds measured at five sites in 45 breast-fed and 41 formula-fed infants. The first component represented fatness, the second component change in fatness, and the third component upper body/lower body fat distribution. Analysis of the components indicated that fatness and the proportion of lower body fat were greater in breast-fed than in formula-fed infants; however, when race was included as a predictor, the differences in lower body fat did not persist. The interpretation of components and the group differences were confirmed by repeated measures analysis of variance (ANOVA) on the sum of skinfolds (fatness) or simple skinfold ratios (fat distribution). Group differences for fatness and upper body/lower body fat persisted when race was included as a predictor. Longitudinal PCA of another indicator, the Rohrer index, suggested that fatness was greater in formula-fed than breast-fed infants. Collectively, these findings suggest that formula-fed infants have less subcutaneous fat than breast-fed infants; however, formula-fed infants may have either more internal fat or more lean body mass. Am. J. Hum. Biol. 9:179-190, 1997. © 1997 Wiley-Liss, Inc.

Precision estimates are given for anthropometric assessment of body fat distribution in participants (n = 86) of the Healthy Growth Study (total n = 154). This five year longitudinal study explored the psychosocial and biologic influences on activity levels in urban adolescent African American girls. The basic anthropometric data include height, weight, four body and limb circumferences, and five skinfold measurements. It is proposed that ratio indices of body fat distribution are likely to have poorer precisions than the single variables which they comprise, and that ratios based on skinfolds may be particularly sensitive to this problem. The precision of the body mass index (BMI) and principal components of skinfold fatness and fat distribution are also considered. Precisions were greater than 0.95 (intraclass correlation from a random-effects analysis of variance) for most anthropometric dimensions and indices, including the BMI and the first principal component of fatness. However, three of the five skinfolds had lower precisions (0.84-0.93). In contrast, the precisions of all indices of body fat distribution were 0.90 or less (range: 0.57-0.87 skinfold ratios; 0.83-0.90 circumference ratios). Of the ratios, conicity was most stable at 0.90 for repeated measures by both the same and different observers. A second principal component of central fat did not have precisions noticeably better than skinfold ratios (0.79-0.82). Indices of fat distribution may have lower reliabilities than the single variables that they comprise, because errors may be compounded when dividing one variable by another or in linear combinations of measurements other than the first principal component. This problem should be taken into account in clinical and epidemiologic investigations of body fat distribution. © 1996 Wiley-Liss, Inc.

"Conicity" (C) is an index of body fat distribution which expresses an individuals waist circumference relative to the circumference of a cylinder generated with that persons weight and height assuming a constant for body density (Valdez [1991] J. Clin. Epidemiol. 44:955-956). The more central a person is in fat distribution, the higher the value of C. In a pilot study of cardiovascular reactivity and dimensions of anger and hostility in 60 African-, Anglo-, and Hispanic-American adolescents, anthropometry and sexual maturation were determined to assess their mediating influence on the relation between anger and cardiovascular risk. The concurrent validity of three indices of body fat distribution was explored: conicity(C), waist/hip ratio (WHR), and central/peripheral skinfold ratio (C/P) by assessing their association with cardiovascular variables (CV) and other anthropometrics. Anthropometry included height, weight, fat mass estimated from bioelectrical impedance, four circumferences, and skinfolds. Maturation variables included menarche in girls, testes size in boys, and pubic hair in both sexes. Cardiovascular variables included resting diastolic and systolic blood pressures and heart rate, and the same three variables after recovery from a step test. The boys and girls were 15-16 years of age, and there were equal numbers in each sex/ethnic group. Partial correlations accounting for height (which was affected by ethnicity) and maturation stratified by gender are reported. C was more strongly related to CV risk in boys and girls than the other indices or the body mass index. Least related to CV risk was C/P, correlated only weakly to central skinfold fat. C and WHR are highly related (0.85) yet differ in important respects in both sexes: C is more closely related to body fat (0.62-0.66) and fat mass (0.53-0.77) than the WHR (respective correlations: 0.54-0.55 and 0.43-0.66). Thus, C relates not only to body shape but also to body fat. Indices of central fat such as circumference and skinfold ratios, may "over-correct" for total fatness and thus miss important aspects of risk prediction. Conicity may be a useful indicator of body fat distribution in studies of adolescents. © 1996 Wiley-Liss, Inc.

Skinfolds at five anatomic sites were measured on 47 subjects in a study of gallbladder disease in Starr County, Texas, by two methods, one and two handed. A comparison was made of the two methods as to bias and precision. There were statistically significant but biologically unimportant differences (on the order of 1-2 mm) at four of the five sites. At three of these, the two-handed method gave larger values (lower thigh, triceps, and subscapular), and at the other site (medial calf) this method produced smaller values on average. Measurement precision was improved using the two-handed method at three of the five sites, significantly so for the triceps skinfold. Measuring skinfolds with two hands improves the precision of measurement for some skinfold sites in obese individuals. It does not introduce important and systematic biases across skinfold sites. Adoption of this technique should be used when circumstances outweigh the cost of involving an extra observer in the measurement of skinfold thickness, such as when precision is very important and when subjects are obese. © 1995 Wiley-Liss, Inc.

Precision estimates are given for indices of body mass, fatness and body fat distribution in a sample of n = 19 subjects selected at random from a larger study of cardiovascular disease risk in school-aged children. The value of this study is that little is known about the measurement precision of ratio indices and multivariate constructs of body fat distribution in children or any other age group. Intra- and inter-observer precisions were highest for weight, height, body mass index and six body circumferences (0.95-0.99), and were lower and more variable for five skinfold thicknesses (0.80-0.99). The measurement precision of ratio indices derived from the circumferences (waist/hip and waist/thigh) and the skinfolds (subscapular/thigh and triceps/subscapular) were lower and more variable than precisions of the single variables. Circumference ratio precisions varied from 0.81 to 0.96 and skinfold ratios varied from 0.28 to 0.94. Precisions of a multivariate construct of central fat distribution from five skinfold measures were better (0.77-0.95), suggesting its greater efficacy. Inter-examiner precisions tended to be significantly lower than intra-examiner precisions for skinfold thicknesses and all composite indices. The lower precisions of ratio indices, compared to the measurement accuracy of the variables which make them up, needs to be considered in epidemiological studies of body fat distribution.

Upper and centralized body fat distribution is associated with non-insulin dependent diabetes mellitus (NIDDM). Few studies have focused on anthropometric characteristics of preadults from families in which there is a diabetic (NIDDM) proband. This study explores the prevalence of upper and centralized body fatness in Mexican American children from the Diabetes Alert study (1981-1983) in Starr County, Texas. Anthropometric data on 165 males and 224 females 9-19 years include measures of adiposity such as skinfold thicknesses and the body mass index (BMI), a measure of overweight. They show rates of obesity two to three times that of White children of comparable age and sex from National Health Surveys. In comparison with U.S. White subjects, Mexican American adults are shorter, have more adiposity and arm muscle mass and have sitting heights and body breadths at the mean of these dimensions for the U.S. Population Children from Diabetes Alert families show only marginal excess of severe obesity (> 95th percentile of BMI) when compared to the general population of children surveyed in Starr County schools. Girls from these families, but not boys, have excess fatness in the BMI compared to Mexican American children from the Hispanic Health and Nutrition Examination Survey (HHANES); suprailiac skinfold thicknesses are also greater in children of the Diabetes Alert study than in HHANES children. From 1972 through 1982, Mexican American children in South Texas showed an increase in average stature, weight, and the BMI. These data together suggest that excessive obesity exists and may be increasing in children in populations at risk for NIDDM. The prevention of NIDDM in the Mexican American population may be more effective if educational and promotional interventions include the school aged population. © 1993 Wiley-Liss, Inc.

A positive relationship between psychosocial stress and central body fat distribution has been hypothesized. To test this hypothesis, two indices derived from principal components analysis of four skinfold measurements were studied in relation to imputed job stress characteristics (decision latitude, skill discretion, decision authority, and psychological demands) in Mexican-American men of the U.S. Hispanic Health and Nutrition Examination Survey (HHANES). The two indices were fatness and central body fat distribution. Fatness was not significantly associated with any of the job stress characteristics before controlling for education. Once education was included in the equations, however, the relationship between fatness and two of the four job stress variables (decision authority and psychological demands) became statistically significant. Thus, for a given level of education, increasing job stress was associated with increasing fatness. Three of the four job stress characteristics were significantly associated with central body fat distribution before controlling for education. However, after education was entered into the regression equations as a proxy for social class, the relationships between central body fat distribution and the job stress variables were no longer significant. It thus appears that aspects of social class other than job stress are of equal or greater importance in predicting body fat distribution. © 1992 Wiley-Liss, Inc.

The authors studied the association of cardiovascular risk variables with body fat distribution (BFD) in a cross-sectional sample of 743 Texas schoolchildren of both sexes ages 6-14 years. This association is well known in adults and several useful indices of BFD are available. Whether they are applicable to children remains a question of importance for epidemiological investigations in this age group. Canonical correlations between anthropometric (five skinfolds, four circumferences) and risk (blood pressures, cholesterol, pulse) variables ranged from 0.37 to 0.82 depending on sex/age group (p < 0.01). The skinfold vector suggested an association of risk with central fat at most but not all ages. The circumference vectors, on the other hand, suggest that size or fatness, not BFD, was related to risk. Partial correlation and stepwise regression of fatness and BFD indices with cardiovascular risk factors as dependent variables, showed that 'fatness' or 'size' was more clearly associated with risk factors than BFD. The variables most consistently entering the regression were hip circumference and sum of skinfolds. These results contrast with studies of adults or sexually mature adolescents, in which BFD is more clearly related to CV risk variables and the hip circumference is a 'low-risk' variable.

Multivariate associations were sought between risk factor levels (total cholesterol, high density lipoprotein (HDL) cholesterol, triglycerides, glucose, and systolic and diastolic blood pressures) and two sets of anthropometric variables (four circumferences and six skinfolds) to select a set of anthropometric indicators of body fat distribution that correlate most highly with risk of disease. Subjects were men (n = 285) and women (n = 672) from a study of gallbladder disease in a Mexican American population in Starr County, Texas, 1985-1986. The canonical correlations showed that circumferences (0.49-0.61) and skinfolds (0.42-0.60) were equally well correlated to risk factor levels independently of sex and age. Weights from the canonical analyses suggest that measurements at or above the waist and on the lower limb (thigh) are most heavily loaded toward risk (waist = highest risk; thigh = lowest risk). The simplest and most reliable index of body fat distribution for both sexes is the ratio of waist to thigh circumferences. The more commonly used waist/hip ratio proved more valid in women, but not in men. Simple skinfold indices of body fat distribution were more poorly correlated to risk factor levels than the corresponding circumference ratios. In women, body mass index and waist circumference by themselves did as well as body fat distribution indices in explaining variation in risk factors, suggesting the involvement of visceral fat in the body fat/body fat distribution disease relation.

Three indices derived from principal components analysis of four skinfold measurements were studied in relation to socioeconomic status (SES; income and education) in men and women of the U.S. Hispanic Health and Nutrition Examination Survey (HHANES). The three indices were fatness (PC1), central body fat distribution (PC2), and "centralized obesity" (PC1 + PC2). The well-known inverse relation of fatness (PC1) with SES was demonstrated in women. This relationship tended to be positive in men, but not consistently so within the three Hispanic groups (Puerto Rican, Cuban, Mexican-Americans) studied. A negative association of central body fat distribution (PC2) was also evident in both sexes and in all three groups except in Puerto Rican men, in whom the relationship was no longer significant after age adjustments. The third index combined information on both fatness level and central distribution. It was strongly related to SES in women but not in men.

In this paper the hypothesis is tested that circumferences are as useful as skinfolds in children aged 10-14 years to detect variation in regional fat distribution. This would be confirmed by the appearance of a significant canonical correlation between a vector of appropriately selected circumferences and an analogous vector of skinfolds, producing a weighted pattern suggestive of centralized obesity (that is a series of mathematical weights of different signs for central versus peripheral regions of the body). The hypothesis is confirmed (P < 0.01) in this sample of 378 children of both sexes. The association occurs in the second canonical correlation after a strong first canonical correlation providing information about fatness level (0.83-0.87). The canonical correlations are low (0.29 in boys, 0.36 in girls), lower than has previously been reported in a similar study of adults. The circumferences most heavily weighted in opposite directions are the waist and thigh. These results are in accord with adult studies. This study did not support the use of the waist-hip circumference combination, the measures currently used in most epidemiologic studies of body fat distribution.

Reference percentiles (5th, 10th, 50th, 85th, 90th, and 95th) of black and nonblack children ages 8–17 years from Project HeartBeat! (n = 678) are presented for body mass index (BMI), percent body fat (PBF), fat-free mass (FFM), and fat mass (FM) derived from bioelectrical impedance. Project HeartBeat! is a mixed longitudinal study in which three cohorts of children (seen initially at age 8, 11, or 14 years) were followed for 4 years and measured thrice-yearly from 1991 through 1995. Weight, height, and BMI of Project HeartBeat! children are similar in central tendency and variability to those of nationally representative samples for nonblack children but not black children, for whom there is an excess of children at or above the 95th percentile for weight and BMI. Values of PBF above which cardiovascular risk variables increase (as suggested in the literature) are located at the 85th percentile of the Project HeartBeat! distributions. This percentile of PBF may be tentatively considered as a cutoff point with epidemiological significance for children. Am. J. Hum. Biol. 16:135–150, 2004. © 2004 Wiley-Liss, Inc.

This research examined whether the migration history of overweight Mexican-American women had an independent effect on cardiovascular risk factors, or whether it was mediated by health behavior changes.Cross-sectional data from 390 overweight, non-diabetic Mexican-American women (aged 18 to 65 years), all recruited from Starr County, Texas, were used for this analysis. Migration history was inferred from birthplaces of subjects and relatives, and length of residence in the United States. Health behaviors included tobacco and alcohol use, sleeping, exercise, and dietary practices. The cardiovascular disease risk factor variables (CDRFVs) studied were plasma glucose, abdominal obesity, blood pressures, and blood lipids. A migration history score (MHS) was developed from factor analysis, almost equally contributed to by the 9 migration history variables. Healthy habits were defined by 6 variables, and 3 factors (blood pressures, lipids/glucose, and body fat/glucose) were used for the CDRFVs.MHS was correlated positively with socioeconomic status, and negatively with family stress. Older women had healthier drinking and sleeping habits. Women with a higher migration history score exhibited poorer exercise habits, and increased blood pressures. After adjusting for the effect of healthy exercise habits on blood pressures, the impact of migration history on blood pressures became non-significant (P.05), leading to the conclusion that healthy exercise behaviors mediated the negative relationship of MHS with blood pressures. Age was independently positively correlated with all CDRFVs. Age also weakly moderated the negative relationship of MHS and healthy exercise habits.

Background: The State-Trait Anger Expression Inventory (STAXI), a self-report questionnaire, is designed to measure the experience and expression of anger. Reliability and validity of the STAXI have been well established among African and European Americans aged 13 years and older. However, little is known of the use of this instrument among adolescents younger than 13 years and Hispanic American adolescents. Objectives: Objectives were (a) to test ethnic, sex, and age group differences in STAXI scores in a sample of 11-to-16-year-old African, Hispanic, and European American adolescents; and (b) to assess the psychometric properties of the STAXI among these same adolescents with special emphasis on Hispanic youths, for whom no data are available. Methods: A cross-sectional design was used with stratified quota sampling techniques. Participants (N = 394) were African, Hispanic, and European Americans aged 11-16 years and were drawn from one public middle school and two public high schools in Houston, Texas. Results: Internal consistency reliability for the anger scales (STAXI) ranged from 0.61 (anger-in) to 0.91 (state-anger) for the younger group (aged 11-13 years), and 0.68 (anger-in) to 0.88 (state-anger) for the older Hispanic Americans (aged 14-16). No notable differences were seen among the three ethnic groups in regards to internal consistency. Results of factor analyses of the five anger scales were similar to those reported originally by the scale author. Ethnicity and age had statistically significant main effects on the anger scales, and there was only one interaction. Discussion: The use of the STAXI among a tri-ethnic adolescent population is warranted. The anger-in scale may be less reliable, especially among younger adolescents.

Project HeartBeat! is a four year mixed-longitudinal study of the development of cardiovascular risk factors in White and African American children who at baseline comprised three age cohorts 8, 11, and 14 years. This paper focuses on the anthropometric variables which were chosen to reflect body fat and fat-free mass. Selected anthropometric dimensions are compared with those of samples from the combined National Health and Nutrition Examination Surveys I and II to explore the similarities of the samples in terms of central tendencies and variances. The measurements were then explored in terms of their ability to estimate the two compartment model of body composition: fat-free mass (FFM) and body fat (BF) from bioelectrical impedance (BIA). Project HeartBeat! children are slightly larger than NHANES children and have variances that are generally comparable to the national surveys. Over seven percent (7.7%) of children were overweight (BMI) and 25% had 'mild obesity' by %BF. Three different factor analytic methods (incomplete principal components, alpha and maximum likelihood) produced two latent variables from 17 anthropometric dimensions which together accounted for 76-83% of the variation: (1) A body mass factor (F1) which was weighted highly on six circumferences, weight and six skinfolds, and (2) a linear growth factor (F2) which was strongly associated with height, arm length, and sitting height. Triceps, subscapular and midaxillary skinfolds were consistently highly loaded on the body mass factor and their sum was highly correlated to %BF and fat mass (0.90-0.99). This suggests that this sum could be used to estimate fatness in children in studies where the BIA or other body composition techniques are unavailable. FFM and %BF were predicted from the anthropometric factors. Both factors contributed to the estimate of FFM (R(2) = 0.81-0.93), although F2 contributed proportionately more. The 'body mass' factor (F1) was the main predictor of %BF (R(2) = 0.86-0.93), though at some ages the linear factor (F2) was significantly and negatively related to %BF. This set of anthropometric dimensions, taken for the purpose of estimating body composition and summarized as two latent vectors by factor analysis, strongly reflects body fat and FFM in children and adolescents. Am. J. Hum. Biol. 11:69-78, 1999. Copyright 1999 Wiley-Liss, Inc.

To identify the best variable or combination of sexual maturity variables to use in investigations of adolescent health, and explore possible re-scaling of five-stage sexual maturity stages into dummy variables' ('advanced'/'delayed').Cross-sectional.Tri-ethnic sample of 384 US adolescents 11-16 years of age (Heartfelt Study).Sexual maturity variables are genital. breast and pubic hair stages obtained by clinical examination by nurse practitioners, testes size, menarche and age at menarche.Principal factor analysis of sexual maturity variables, height and age, revealed high commonality among the variables, as no more than a single factor appeared in 27 of 28 factor analyses (by sex and age groups). Genital stage (boys) and breast stage (girls) were most highly related to the first principal factor independent of age and ethnicity. ANOVA of 'key variables' indirectly reflecting endocrine function suggested that some stages could be combined.A single variable should suffice to describe sexual maturity at the studied ages, or variables could be combined in a (unstandardized) sexual maturity index (SMI): SMI (Girls)=0.998 x BREAST+0.900 x PUBIC HAIR + 1.815 x YEARS SINCE MENARCHE. SMI (Boys)= 1.104 x GENITAL + 1.328 x PUBIC HAIR + 5.997 x TESTES SIZE (mL).

This study explores the potential influence of growth, body/composition, and sexual maturity on the relation of anger expression and blood pressure in adolescents. Baseline data from Project HeartBeat! (82 boys and 85 girls, 14 years of age) examined the ability of anger expression (STAXI scale) to predict blood pressure, after controlling for the effects of ethnicity (African-American/non-African-American), height, weight, percentage body fat, and sexual maturity. Blood pressures were unrelated to anger expression in models that included the above developmental variables. However, girls scoring high on healthy anger expression (“anger-control”) had significantly lower levels of percentage body fat (P = 0.015) independent of the above factors. The literature suggests that body fat or body mass is often, though not unanimously, associated with unhealthy forms of anger expression in adolescents. Research is required into the biological, social, and behavioral origins of the association between body fat and anger expression. Height and sexual maturity, virtually ignored in this literature, should be included in future research. Am. J. Hum. Biol. 13:531–538, 2001. © 2001 Wiley-Liss, Inc.

Hostility, a phenomenon that has been linked to cardiovascular disease and all-cause mortality, is often measured by the Cook-Medley hostility (Ho) scale. Although there is an adolescent version of the Ho scale, it has had little testing with only Anglo-American samples. This pilot study tested the reliability and validity of the adolescent version of the Ho scale with a multiethnic sample of adolescents. Sixty adolescents participated. Reliability was measured using Chronbach's alpha. The Ho scale was correlated with the Speilberger State-Trait Anger Expression Inventory (1988) scales to determine concurrent validity. A factor analysis assessed construct validity; content validity was assessed by analyzing tape-recorded descriptions of a circumstance that provoked anger, as remembered by each adolescent. Internal consistency reliability was .75. The hostility measure was most highly correlated with anger expression (r = .62, p = .000) and trait anger (r = .50, p = .000). The factor analysis generated three factors (suspicious alienation, cynical aggression and justified mistrust), that accounted for 34.5% of the variance. The content analysis resulted in five anger-provoking themes: aggression, unfulfilled personal expectations, mistrust/lying, criticism of effort, and rejection. The majority of items in the scale (74%) were related to one of the themes.

The objective of this cross-sectional study was to determine the relationship between hyperandrogenemia and blood pressure in women with menstrual irregularities seen at an endocrinology clinic. Women with serum testosterone levels (T) ≥ 30 ng/dL were more likely to have general obesity (odds ratio [OR] = 6.8, 95% confidence intervals [CI] = 2.2–27.2) and central obesity (OR = 14.5, 95% CI = 6.1–38.7) than euandrogenemic women. Hyperandrogenemic women (HA) had an OR of 2.4 (95% CI = 1.0–6.2) for elevated SBP and an OR of 2.7 (95% CI = 0.8–8.8) for elevated DBP, independent of age and ovulatory status. Obese HA had an OR of 4.7 (95% CI = 2.3–10.4) for elevated SBP and an OR of 2.9 (95% CI = 1.9–9.9) for elevated DBP. In conclusion, T is associated with an increased risk for obesity and central adiposity. T predicts BP elevation independent of age and ovulatory status. There was a synergistic relationship between obesity and androgens in their affect on BP.

"Conicity" (C) is an index of body fat distribution which expresses an individuals waist circumference relative to the circumference of a cylinder generated with that persons weight and height assuming a constant for body density (Valdez [1991] J. Clin. Epidemiol. 44:955-956). The more central a person is in fat distribution, the higher the value of C. In a pilot study of cardiovascular reactivity and dimensions of anger and hostility in 60 African-, Anglo-, and Hispanic-American adolescents, anthropometry and sexual maturation were determined to assess their mediating influence on the relation between anger and cardiovascular risk. The concurrent validity of three indices of body fat distribution was explored: conicity(C), waist/hip ratio (WHR), and central/peripheral skinfold ratio (C/P) by assessing their association with cardiovascular variables (CV) and other anthropometrics. Anthropometry included height, weight, fat mass estimated from bioelectrical impedance, four circumferences, and skinfolds. Maturation variables included menarche in girls, testes size in boys, and pubic hair in both sexes. Cardiovascular variables included resting diastolic and systolic blood pressures and heart rate, and the same three variables after recovery from a step test. The boys and girls were 15-16 years of age, and there were equal numbers in each sex/ethnic group. Partial correlations accounting for height (which was affected by ethnicity) and maturation stratified by gender are reported. C was more strongly related to CV risk in boys and girls than the other indices or the body mass index. Least related to CV risk was C/P, correlated only weakly to central skinfold fat. C and WHR are highly related (0.85) yet differ in important respects in both sexes: C is more closely related to body fat (0.62-0.66) and fat mass (0.53-0.77) than the WHR (respective correlations: 0.54-0.55 and 0.43-0.66). Thus, C relates not only to body shape but also to body fat. Indices of central fat such as circumference and skinfold ratios, may "over-correct" for total fatness and thus miss important aspects of risk prediction. Conicity may be a useful indicator of body fat distribution in studies of adolescents. © 1996 Wiley-Liss, Inc.

The aim of this study was to determine whether subcutaneous fatness and fat distribution differ on the basis of feeding practice and sex during the first 6 months of life. Longitudinal principal components analysis (PCA) was done on skinfolds measured at five sites in 45 breast-fed and 41 formula-fed infants. The first component represented fatness, the second component change in fatness, and the third component upper body/lower body fat distribution. Analysis of the components indicated that fatness and the proportion of lower body fat were greater in breast-fed than in formula-fed infants; however, when race was included as a predictor, the differences in lower body fat did not persist. The interpretation of components and the group differences were confirmed by repeated measures analysis of variance (ANOVA) on the sum of skinfolds (fatness) or simple skinfold ratios (fat distribution). Group differences for fatness and upper body/lower body fat persisted when race was included as a predictor. Longitudinal PCA of another indicator, the Rohrer index, suggested that fatness was greater in formula-fed than breast-fed infants. Collectively, these findings suggest that formula-fed infants have less subcutaneous fat than breast-fed infants; however, formula-fed infants may have either more internal fat or more lean body mass. Am. J. Hum. Biol. 9:179-190, 1997. © 1997 Wiley-Liss, Inc.

Precision estimates are given for anthropometric assessment of body fat distribution in participants (n = 86) of the Healthy Growth Study (total n = 154). This five year longitudinal study explored the psychosocial and biologic influences on activity levels in urban adolescent African American girls. The basic anthropometric data include height, weight, four body and limb circumferences, and five skinfold measurements. It is proposed that ratio indices of body fat distribution are likely to have poorer precisions than the single variables which they comprise, and that ratios based on skinfolds may be particularly sensitive to this problem. The precision of the body mass index (BMI) and principal components of skinfold fatness and fat distribution are also considered. Precisions were greater than 0.95 (intraclass correlation from a random-effects analysis of variance) for most anthropometric dimensions and indices, including the BMI and the first principal component of fatness. However, three of the five skinfolds had lower precisions (0.84-0.93). In contrast, the precisions of all indices of body fat distribution were 0.90 or less (range: 0.57-0.87 skinfold ratios; 0.83-0.90 circumference ratios). Of the ratios, conicity was most stable at 0.90 for repeated measures by both the same and different observers. A second principal component of central fat did not have precisions noticeably better than skinfold ratios (0.79-0.82). Indices of fat distribution may have lower reliabilities than the single variables that they comprise, because errors may be compounded when dividing one variable by another or in linear combinations of measurements other than the first principal component. This problem should be taken into account in clinical and epidemiologic investigations of body fat distribution. © 1996 Wiley-Liss, Inc.

Blood pressure and body mass index (BMI) are first considered independently, and then jointly, on the basis of both cross-sectional and longitudinal epidemiologic studies. The relations between these two attributes are investigated further by analysis of the “velocity curves” of age increments, from ages 6 to 24, in both blood pressure (systolic and fifth-phase diastolic) and BMI, from data from the US Health and Nutrition Examination Survey, 1971–1974. The results of both reported studies and the present exploratory analysis indicate sometimes strong but quite variable relations between blood pressure and BMI, which differ by age, gender, and the particular blood pressure measure under consideration.

The association of body fat distribution with single and combined site osteoarthritis was investigated using data from the US Health Examination Survey I, 1960-1962 (HES I) and the first National Health and Nutrition Examination Survey I, 1971-1975 (NHANES I). The study included 1,636 adults aged 35-79 years from HES I with hands and feet radiographs and four anthropometric fat distribution measures--subscapular and triceps skinfolds, waist girth, and seat breadth--and 3,885 adults aged 45-74 from NHANES I with knee radiographs and subscapular and triceps skinfold measures. Sex-specific data, adjusted for age, race, and body mass index, were analyzed using polychotomous logistic regression. There was a positive association of body mass index with knee osteoarthritis and with combined hands and feet osteoarthritis. A peripheral body girth pattern was associated with combined site osteoarthritis of the hands and feet; however, there was no consistent pattern of association of body fat distribution with knee osteoarthritis nor with osteoarthritis of the hands or feet only. These findings suggest that the central body fat pattern observed in previous studies to be associated with cardiovascular and gallbladder disease, and with diabetes, is not associated with osteoarthritis of the hands, feet, or knees.

Differences between lowland and highland peoples of the Andes in body size and shape have intrigued students of the hypoxia of altitude for a century or more (see, e.g., Forbes, 1870). Until recently, most of the studies of growth and adult size have, however, focused mainly on the variability of single measurements rather than the use of anthropometric indices or summary measures of multiple anthropometric observations, such as principal components, to assess body proportion or shape. Although not without some inconsistency, these studies have nonetheless described in considerable detail the effects of altitude on body size (for a review, see, Frisancho, 1978). Collectively, they suggest that the main effects are on size for age during growth, but altitude may also affect body proportions and in particular, chest dimensions suchwise as to enhance functional adaptation to the hypoxia of altitude (Frisancho and Greksa, 1989). Ethnicity, on the other hand, appears to have a greater effect on body proportions rather than size. The Aymara, for example, have relatively larger sitting heights, more prominent heads and bony diameters than non-Aymara when altitude is held constant (Palomino, Mueller, and Schull, 1979). However, as commonly used, ethnicity measures population genetic differences rather than actual heritability, and in comparisons between populations living at different altitudes or even within the same altitude, regional differences in environmental factors may be confounded with genetic effects to a greater or lesser extent.

P64 Background: To study the relationships of changes in anthropometric variables - height, weight, and body mass index (BMI) - to changes in blood lipids (TC, LDL-C, HDL-C and TG) in children and adolescents aged from 8 to 18 years. Methods and Results: Cohorts of three different age levels 8, 11 and 14 years at baseline were enrolled in the study. Each member of these three cohorts was examined three times per year for up to four years. The composition of the study population and the descriptive statistics for the continuous variables at baseline were summarized. Ethnicity was categorized as Black (21.1%) and non-Black (79.9%). Non-Black includes White (74.6%), Hispanic (3.7%), Asian (1.0%) and American Indian (0.6%). The relationships of changes in anthropometric variables and in blood lipids were evaluated by adding height, weight, or BMI and associated interaction terms separately to the basic age-sex models, derived in previous analyses. A multilevel modeling technique was used. Likelihood ratio tests were conducted by calculating the deviation of -2log(likelihood) within the basic model and alternative models. Height or height gain had significant negative associations with changes in TC, LDL-C and HDL-C with estimated coefficients of -0.763, -0.448 and -0.301, respectively. The estimated coefficients between weight gain and changes in TC, LDL-C and TG were 0.337, 0.370 and 0.1473, respectively, and -0.305 for HDL-C. The estimates of relationships between changes in BMI and in TC, LDL-C, HDL-C and TG were 2.122, 1.884, -0.885 and 4.673, respectively. An interaction between weight (or BMI) and ethnicity was significant in the models for triglycerides only. Sex-Age interactions were significant in most models. Effective effects of race were significant in the models for LDL-C, HDL-C and TG. Conclusions: The results of this longitudinal analysis indicated a very strong association between increasing BMI and changes in blood lipids within the period of childhood and adolescence. These findings have implications for assessing changes in blood lipids, especially among those experiencing the greatest increases in BMI.

This study seeks the relationship between socioeconomic status (S.E.S.), obesity and non‐insulin dependent diabetes mellitus within the Starr County population of South Texas. The study used data from the first phase of the Diabetes Alert Study, constituting a random sample of 1,926 adult individuals. The prevalence of obesity (Wt/Ht2>30) in this population was twice that of the U.S. population (20–22%), but less than a 30% rate was observed in extended families of diabetics in Starr County. An inverse relationship between socioeconomic status and obesity was found among women (p