Impact of pubertal development on body fat distribution among white, Hispanic, and Asian female adolescents.

Variation in the waist/hip ratio (WHR) may be related to changes in hormonal secretion associated with pubertal maturation. We therefore studied the effects of race, pubertal development, and body fatness on WHR during adolescence in a multiethnic population. A total of 688 white, Asian, and Hispanic female adolescents (mean (+/- SD) 12.4 +/- 0.7 years), participating in the evaluation of a multisite school-based health education program, were included in these analyses. Self-assessed stage of puberty and measurements of height, weight, waist circumference, and hip circumference were obtained from each participant. The WHR and age-adjusted body mass index were calculated. Analysis of covariance demonstrated that puberty significantly affects hip circumference and WHR but not waist circumference among female adolescents. Age and fatness, as reflected by age-adjusted body mass index, contributed significantly to both circumferences and to the WHR. There was a significant effect of ethnicity on hip circumference but not on waist circumference or the WHR. These results confirm that pubertal stage exerts a significant effect on the hip circumference and WHR in female adolescents, even after the effects of fatness and age are controlled. Studies of body fat distribution during late childhood and adolescence should include assessments of pubertal maturation.

Anorexia nervosa, athletics, and amenorrhea.

We examined menstrual function in two groups of patients meeting the DSM III criteria for anorexia nervosa who differed only in their physical activity. Sixteen athletes with anorexia nervosa were compared with eight sedentary patients who had anorexia nervosa. Athletic patients with anorexia were found to have lower gonadotropin levels, a longer period of amenorrhea both before significant weight loss and after weight rehabilitation, and a higher weight at the time of resumption of menses than patients with anorexia who were sedentary. However, both groups were markedly undernourished, had amenorrhea before significant weight loss and after weight rehabilitation, and had lower gonadotropin levels than normal subjects. These data suggest that the increased physical activity often seen in patients with anorexia nervosa worsens, but does not cause, menstrual dysfunction.

Identifying adolescents at risk for noncompliance with contraceptive therapy.

The sociomedical characteristics of 96 sexually active adolescent females have been studied in order to understand noncompliance with the contraceptive prescription, an important antecendent of adolescent pregnancy. Compliance was found to correlate positively with postmenarchal age, frequency of intercourse, autonomy in making and paying for a clinic appointment specifically for the purpose of obtaining contraception, and acceptance of a method at the time of the initial clinic visit. These findings serve to alert the pediatrician to the adolescent at risk for noncompliance before the experience of failure, and in so doing to identify those in need of special assistance to ensure the success of contraceptive measures.

PIP: 96 sexually active adolescent females attending the Stanford University Adolescent Clinic of the Dept. of Pediatrics between 9/76 and 11/78 were studied to determine factors which contribute to noncompliance with contraceptive prescription, an important antecedent of adolescent pregnancy. 15 variables were selected for the study and included information on demographic characteristics; medical history; patterns of sexual activity; physical development; and motivation for clinic attendance. Chi-square and stepwise discriminant analyses were the analytical methods used. Mean age of study group was 15.9 years; slightly more than half were blacks. One-third of the group had parental knowledge of their sexual activity. Almost 2/3 had a single sex partner, and mean duration of sexual relationship was nearly 1 year. More than 1/3 had intercourse less often than once a week. Half of the patients had initiated their own clinic appointment, while the remaining were influenced by parents, physicians and others. 44% of the subjects complied with the contraceptive regimen during the study period. Adolescents who paid for their own medical care; who had a single sex partner; who were sexually active more often than weekly; who made their own clinic appointments; and who came to the clinic themselves desiring birth control were more likely to be compliant than the others. Using standardized discriminant function coefficient for 6 variables (computed compliance values; method of payment; method of birth control; frequency of intercourse; appointment source; agenda source), patients were correctly assigned to the compliant or noncompliant group in 72% of the cases. Implications of these findings, and the role of the primary care physician in the prevention of adolescent pregnancy, are discussed.

Isoniazid hepatitis in adolescents.

Prophylactic isoniazid therapy is currently recommended for adolescents with positive tuberculin reactions because of the risk of activation of tuberculosis in this age group. Since this drug has been associated with hepatic dysfunction in adults, the present study was undertaken to evaluate its effect on liver function in teen-agers. Accordingly, liver function tests were performed on 178 adolescents prior to and following administration of INH. Abnormalities in SGPT values were encountered in 10% of these patients and occurred in the main within the first 10 weeks of testing, suggesting INH maybe hepatotoxic. However, jaundice was notably absent in the patients with enzyme elevations and prompted a further investigation into the possible effect of INH on bilirubin metabolism. Thus, Sprague-Dawley rats were given four daily injections of INH. These animals manifested increased hepatic bilirubin glucuronyl transferase activity when compared with control rats, supporting the hypothesis that enzymatic induction may be responsible for the absence of jaundice in our adolescent subjects.