Resting blood pressure and pulse rate distributions in black adolescents: The Philadelphia Blood Pressure Project.

Reference percentile distributions for blood pressure in black adolescents are not generally available. The most recently published BP percentile grids for children and adolescents were derived almost exclusively from information on white populations, and few data are available on the distribution of pulse rate for black adolescents. Reference percentiles for black adolescents for resting BP and 60-second pulse rate are presented. Given the tendency for high BP levels to track, these reference percentiles may be of value in determining the extent to which black adolescents are at risk for hypertensive disorders in adulthood. The percentiles were derived from a 3-year longitudinal study of black, urban Philadelphia adolescents, aged 12 to 17 years. Confirming results from studies of other populations in adolescence, a trend was found toward increased mean systolic BP for boys (P less than .001), and that boys have significantly higher (P less than .001) systolic BP than girls after chronologic age 15 years. Diastolic BP phase IV (muffling) exhibits no age or sex trends from ages 12 to 17 years, but adolescent girls overall have significantly higher (P less than .001) phase V diastolic (disappearance) than boys. Sixty-second pulse rate declines for both boys and girls in adolescence, although at every age 60-second pulse rate means are significantly faster in girls than boys (P less than .02). For girls older than 12 to 17 years, there is a significant, positive correlation between pulse rate and systolic BP (r = .16, P less than .01) and between pulse rate and phase IV diastolic (r = .23, P less than .01).(ABSTRACT TRUNCATED AT 250 WORDS)

Blood pressure, growth and maturation from childhood through adolescence. Mixed longitudinal analyses of the Philadelphia Blood Pressure Project.

This paper presents data on the extent to which blood pressure (BP) and growth status at 7 years of age are associated with BP, growth, and maturity status during adolescence. Two samples of black adolescents, namely, a representative sample (n = 562) stratified by sex and age (11 to 15 years) and a sample (n = 256) with supine BP over one standard deviation above the mean at 7 years of age (High BP7), were selected from the Philadelphia Collaborative Perinatal Project (CPP) population and followed longitudinally for 3 years. When the subjects reached adolescence we again measured supine blood pressure, height, weight, and skeletal maturity. Analyses of the data collected at 7 years of age by the CPP indicated that weight and height are highly significantly associated with systolic blood pressure (SBP) and diastolic blood pressure (DBP) respectively. Accordingly, the SBP, DBP, weights, and heights of the representative sample at age 7 were divided into percentile groupings (< 15%, 15%-85%, > 85%). Using mixed longitudinal analyses during adolescence, we found that mean SBP tracked in males through age 15 and in females through age 13 based on the percentile groupings of SBP, height, and weight. Moreover, the weight percentile groupings provided the best discrimination of SBP at these ages. Skeletal age also tracked throughout early adolescence using these percentile groupings of 7-year heights and weights. In females only, diastolic phase 4 (DBP4) during adolescence was significantly associated with 7-year height percentile groupings. In comparing the representative and the High BP7 samples at each chronological age for BP, height, weight, and skeletal age at adolescence (ages 12 to 17 years), it was found that the High BP7 sample was, on the average, taller and heavier at age 7 and throughout early adolescence. At age 17 in males, however, there were no significant differences in BP, growth, or maturity status. In females, SBP of the High BP7 sample remained significantly higher, and there was a tendency for them to remain heavier through age 17. Hence BP variation is so closely associated with growth and maturation that these factors must be taken into account when assessing BP in childhood and adolescence.

Differences between populations in body shape of children and adolescents.

Growth is marked by changes in body shape as well as increase in body size. It is suggested that changes in body shape in childhood and adolescence be analyzed by least squares fit lines for one dimension on a second at successive ages. These are preferred during childhood to the traditional indices of anthropologists because body proportions change with growth, and one can identify the direction of the change and observe which body dimension is changing, or if both are. Furthermore, populations may be compared by analysis of covariance for different patterns of growth related to sex and ethnic groups. Analysis of a number of populations have demonstrated clear differences between the sexes and between populations for the following body proportions: sitting height to leg length, arm length to leg length, biacromial width to biiliac width.

Differences between ethnic groups in sex dimorphism of adult height.

An analysis has been made of sex dimorphism in adult height using data from 58 Negroid, 76 European, and 67 Amerindian populations. Regression analyses were carried out on the sex difference and sex average of male and female stature means. The greatest sex dimorphism was found in Amerindians and the least in Negroid populations. Data from 36 Asiatic and 27 New Guinea populations have also been considered. It seems that sex dimorphism in adult height has a strong genetic component, making it inappropriate as a measure by which to judge the health and nutritional status of a population.