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OBJECTIVES: To evaluate the impact of early, mid-onset, and late maturation, as assessed by timing of menarche, on height, height velocity, weight, body mass index, and sum of skinfolds in a group of white and black girls. STUDY DESIGN: The Growth and Health Study recruited 9- and 10-year-old girls from Richmond, California, Cincinnati, Ohio, and Washington, DC. There were 616 white and 539 black participants recruited at age 9 and 550 white and 674 black participants recruited at age 10. Participants were seen annually for 10 visits. Longitudinal regression models were used to test for differences in each growth measure by timing of menarche across all ages and to determine whether these differences change with age. RESULTS: Mean age at menarche among white participants was 12.7 years, and among black participants, 12.0 years. According to race-specific 20th and 80th percentiles, early maturers were tallest at early ages and shortest after adult stature had been attained. Peak height velocity and post-menarche increment in stature were greatest in early maturers and least in late maturers. Weight was greatest in early and least in late maturers, as was body mass index. Sum of skinfolds was also greatest in early and least in late maturers. There was no impact of timing of maturation on two common measures of regional fat distribution. CONCLUSIONS: Girls who matured early were shorter in early adulthood, despite having greater peak height velocity and post-menarchal increment in height. Throughout puberty, early maturers had greater ponderosity and adiposity, although there was no association with regional distribution of fat.

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In order to develop standards for upper lip hair in adolescent girls, 4693 observations in 856 black and white subjects were made over 9 years. Up to 2 years after menarche, 90% of girls had no upper lip hair. More than 2 years after menarche, 48.8% of black girls and 9.0% of white girls had small amounts of upper lip hair. This may be more significant in adolescent girls than in older women.

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OBJECTIVE: To determine the association of overweight and central adiposity with cardiovascular disease risk factors in black and white 9- and 10-year-old girls. DESIGN: Cross-sectional analysis of baseline data collected from participants in the National Heart, Lung, and Blood Institute Growth and Health Study. Girls were classified as overweight or not with the use of the age- and sex-specific 85th percentiles of the body mass index (kilograms per square meter) distributions from the combined NHANES (I and II) data set. Mean indexes of central adiposity, blood pressure levels, and lipid concentrations and the clustering of risk factors based on published cut points were compared between weight groups by race and by central adiposity group within weight and race groups. RESULTS: Overweight was associated with increased risk factor levels and with increased clustering in both black and white girls. Among overweight girls greater central adiposity was associated with higher risk factor levels and increased clustering. CONCLUSIONS: Given the associations between cardiovascular disease risk factors and both overweight and central adiposity, the secular trends toward increased obesity in American youth portend a worsening of cardiovascular disease risk profiles.

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PURPOSE: To evaluate the relationships of overweight and fat patterning with cardiovascular disease (CVD) risk factors in black and white boys. DESIGN: Cross-sectional analysis of CVD risk factors by weight and central adiposity groups in black and white boys, aged 10 to 15 years. Mean adiposity, lipid, and blood pressure variables were compared between weight and central adiposity groups within race by using linear regression models. Observed clustering of risk factors within weight and adiposity groups was compared with the expected clustering under an assumption of no association. RESULTS: Within each racial group, overweight boys had greater skinfolds, lower high-density lipoprotein cholesterol levels, higher low-density lipoprotein cholesterol and triglyceride levels, and higher systolic and diastolic blood pressure than non-overweight boys. Among overweight boys, greater central adiposity was associated with higher risk factor levels and increased clustering of risk factors. CONCLUSION: Overweight and central adiposity together profoundly affect CVD risk factor levels and risk factor clustering in black and white boys.

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OBJECTIVE: To compare pubertal maturation, sex steroid hormones, and lipoproteins and their interrelationships in male offspring of parents with premature coronary heart disease (cases) and a control group. DESIGN: This was a cross-sectional comparison of cases and members of a control group 10 to 15 years of age. SUBJECTS AND METHODS: Offspring were recruited from patient lists of area physicians. Members of the control group were recruited from area schools. Body mass (kg/m2), serum lipids, lipoproteins, apolipoproteins, estradiol, and free testosterone were measured. RESULTS: Differences in age were not significant, but offspring were taller, heavier, and more mature. Offspring had higher total and low density lipoprotein cholesterol. Offspring had lower estradiol levels in early puberty but higher levels in late puberty. With family history and body mass in the regression models for lipid parameters, free testosterone was a significant explanatory factor for total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein, and estradiol was a significant predictor for apolipoprotein B. The percent of the variance in the lipid parameters explained by testosterone and estradiol was small. CONCLUSION: Sex hormone concentrations appear to be modest but significant predictors of lipoprotein and apolipoprotein concentrations in offspring and a control group in cross-sectional analysis. After controlling for pubertal maturation, hormone and lipid concentrations differed in offspring and the control group.

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OBJECTIVES: The objectives of this study were to determine which factors in early pubertal girls might be predictive of later, severe facial acne. STUDY DESIGN: The study was a 5-year longitudinal cohort study, with yearly visits from 1987 through 1991, in a volunteer sample of 439 black and 432 white fourth- and fifth-grade girls with consent from their legal guardians. The subjects were recruited from public and parochial schools in Cincinnati, Ohio. The degree of facial acne was classified annually as mild, moderate, or severe. Blood samples were obtained at the first, third, and fifth years of the study. Using the acne status during the fifth year of the study as the outcome variable, we determined the contributions from the prior acne status and the serum levels of dehydroepiandrosterone sulfate (DHEAS), testosterone, free testosterone (FT), estradiol (E2), progesterone, and testosterone-estrogen binding globulin (TEBG) and compared the results at various ages and at times before and after menarche. RESULTS: No racial differences in acne or hormone levels were found. There was a progressive increase in the number of acne lesions with age and maturation. The girls exhibited many more comedonal than inflammatory acne lesions, regardless of age. The girls in whom severe acne developed by the fifth year of the study had significantly more comedones and inflammatory lesions than girls with mild or moderate acne, as early as age 10 years, approximately 2 h years before menarche, a time when their degree of acne was mild. Girls with mild comedonal acne had significantly later onset of menarche (12.5 compared with 12.2 years) than girls with severe comedonal acne. Girls in whom severe comedonal acne developed had significantly higher levels of serum DHEAS and, in a longitudinal analysis, somewhat higher levels of testosterone and FT in comparison with girls who had mild or moderate comedonal acne. Serum E2, testosterone/E2, progesterone, and TEBG values were no different in girls with severe compared with mild or moderate comedonal acne. CONCLUSIONS: The early development of comedonal acne may be one of the best predictors of later, more severe disease. The adrenal hormone DHEAS appears to play an important role in the initiation of acne. DHEAS, testosterone, and FT are associated with the perpetuation of severe comedonal acne. Early recognition of young girls at risk of having severe comedonal acne may enable the clinician to intervene and thus prevent unwanted sequelae.

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OBJECTIVE: To identify determinants of resting energy expenditure (REE) in black girls and white girls and to evaluate racial differences in REE. STUDY DESIGN: Cross-sectional study of 98 girls (47 black and 51 white girls), ages 6 to 16 years. METHODS: Determinations of lean body mass, fat mass, and bone mass were made by dual-energy x-ray absorptiometry. Measurements of REE were made with the DeltaTrac metabolic monitor. Subjects fasted at least 3 hours before testing, had rested 30 minutes before the test, and had not engaged in strenuous activity for the previous 12 hours. Pubertal maturation was assessed with a three-stage scoring method: (1) prepubertal, (2) pubertal, but premenarcheal, and (3) postmenarcheal. RESULTS: There were no significant differences in height, weight, lean body mass, or fat mass between the black and white subjects. Racial differences in total REE were also not significant, but REE standardized by weight was significantly greater in white girls (40.3 kcal/day) compared with black girls (35.5 kcal/day) (p = 0.001). Resting energy expenditure was positively and significantly correlated with all measures of body composition. Multiple regression analysis identified lean body mass, sexual maturation, and race as significant main effects. After controlling for lean body mass and maturation, black girls had significantly lower REE. The race-maturation interaction was of borderline significance (p = 0.09); prepubertal black girls had significantly lower REE (1156 kcal/day) than prepubertal white girls (1399 kcal/day), but racial differences in stages 2 and 3 were not statistically significant. CONCLUSION: Lean body mass, maturation, and race are significant determinants of REE. Resting energy expenditure is significantly lower in black than white girls in the prepubertal stage. The cause of this racial difference in REE is not known; it is not explained by differences in anthropometric variables. Racial differences in REE could explain in part the earlier onset of puberty in black girls compared with white girls and could be a factor in the difference in obesity in black and white women.

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OBJECTIVE: To evaluate racial differences in blood pressure in girls aged 9 to 10 years in the National Heart, Lung, and Blood Institute Growth and Health Study (NGHS) and to evaluate the extent to which racial differences in blood pressure are explained by other factors, including sexual maturation and body size. METHODS: The NGHS enrolled 539 black and 616 white girls aged 9 years, and 674 black and 550 white girls aged 10 years. Racial differences in blood pressure were examined. Relationships of stage of sexual maturation, height, and skinfold thickness with systolic and diastolic blood pressure were evaluated by multiple regression analysis. RESULTS: The black girls had significantly higher systolic (102.0 +/- 8.90 vs 100.5 +/- 9.42 mm Hg, p <0.001) and diastolic (58.0 +/- 12.0 vs 56.5 +/- 12.51 mm Hg, p <0.01) blood pressures than the white girls. The black girls were also more advanced in sexual maturation and were taller (142.9 +/- 7.94 vs 139.6 +/- 7.05, p <0.001) and heavier (39.6 +/- 11.24 vs 35.3 +/- 8.73 kg, p <0.001) than the white girls. Both systolic and diastolic blood pressure were significantly correlated with level of maturation, height, weight, and sum of skinfolds. Stage of maturation was found to account for the difference in blood pressure between black girls and white girls. In a multiple regression analysis, controlling for height (for diastolic blood pressure) and for both height and sum of skinfolds (for systolic blood pressure) eliminated the effects of race and stage of maturation on blood pressure. CONCLUSION: Racial differences in blood pressure were observed for 9- and 10-year-old girls and are explained by the fact that black girls were more mature than white girls. The effect of sexual maturation on blood pressure appears to operate through height and body fat. The effect of obesity may be more important for systolic than for diastolic blood pressure. Continuation of racial differences in blood pressure may result in a higher prevalence of hypertension for black women.

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To determine the earliest signs of pubertal maturation, we followed 515 boys, aged 10 to 15 years at intake, every 6 months for 3 years. Changes in age, height, weight, body mass index, and serum levels of sex steroid hormones were significantly related to pubertal stage (PS). The earliest clinical stage of pubertal maturation, designated PS2a, was represented by the absence of public hair and a testicular volume 3 cc or greater; 6 months later, further maturation had occurred in 82% of these boys. Inclusion of PS2a as the earliest stage of puberty may help allay concerns about boys with perceived delayed maturation, and may allow more precise definition of early puberty.

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