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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 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.

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.

The components of reliability for eight anthropometric measures were studied in 95 male and 134 female subjects from the Second National Health and Nutrition Examination Survey (NHANES II). The contributions to unreliability variance (Sr2) that occur as a result of measuring errors (Sp2, imprecision variance) and of intrasubject fluctuations in a measurement due to physiologic factors (Sd2, undependability) were estimated (Sr2 = Sp2 + Sd2). Unreliability was then related to the between-subject variance (S2) to estimate the reliability (R = 1 - (Sr2/S2)) of the measurement. Four of the anthropometric measurements (weight, height, sitting height, and arm circumference) had reliabilities in excess of R = 0.97. In the first three of these, measurement imprecision made up two thirds or less of unreliability, and undependability (Sd2) was stable by two weeks. Lesser but still acceptable reliabilities were obtained for triceps and subscapular skinfolds, bitrochanteric breadth, and elbow breadth (R = 0.81-0.95). For these variables imprecision (Sp2) was the major source of error. Furthermore, the unreliability (Sr2) between observers was twice as high or more than the unreliability within observers for these variables, evidence that imprecision (Sp2) is the single most important source of unreliability in these anthropometric measurements. Unreliability standard deviations of skinfolds increased in a linear manner with skinfold thickness corresponding to an unreliability coefficient of variation of 13-19 per cent. None of the other measurements showed such scale effects. Analyses of the kind suggested will help epidemiologists decide whether reliability can be increased by improving precision, and whether there is a need to improve reliability in the first place. Reliability appears to be adequate for all anthropometry in the NHANES II.

The association between body fat distribution patterns and cardiovascular disease risk variables (high density lipoprotein (HDL) cholesterol, total cholesterol, diastolic and systolic blood pressures, and fasting blood glucose levels) was sought in a sample of Mexican American adults who were studied during 1981-1983 in Starr County, Texas. In the sample, all diabetics were excluded to see whether centralized obesity carried any risk for cardiovascular disease independent of diabetes. A component of centralized body fat distribution was identified through the use of principal components analysis of five skinfold measurements, which included the upper and lower extremities and trunk areas. The centralized obese were compared with generalized (peripheral) obese and nonobese controls in four subgroups of the population: younger and older adult males and females. The means of all cardiovascular risk variables were in a direction indicating that the centralized obese were significantly at greater risk than nonobese controls (in particular, HDL cholesterol, total cholesterol, and blood glucose levels). The generalized obese differed from the centralized obese in having significantly lower blood glucose levels, and tended to be intermediate between centralized obese and nonobese controls in the other variables. The data confirm that centralized obesity as defined by a linear combination of skinfold measures works in the same way as the waist-to-hip circumference ratio in describing a body build factor which heightens the risk of cardiovascular disease in the obese independent of the clinical diabetic state.