Application of the adult international germ cell classification system to pediatric malignant non-seminomatous germ cell tumors: a report from the Children's Oncology Group

BACKGROUND

The purpose of this analysis is to explore whether the International Germ Cell Classification Consensus (IGCCC) tumor marker criteria, developed for adult males with metastatic malignant germ cell tumors (MGCT), are prognostic among pediatric patients and whether tumor marker data may be relevant in pediatric risk stratification.

PROCEDURE

The IGCCC was applied to 436 pediatric germ cell patients treated on Pediatric Intergroup Studies from 1990 to 1996. Multivariable Cox proportional hazards model identified prognostic variables; survival rates among IGCCC risk groups were compared using the log-rank test. Concordance and relative performance of IGCCC versus COG risk stratification was evaluated.

RESULTS

Applying the IGCCC, 21% of pediatric patients were good risk (GR), 35% intermediate risk (IR), and 44% poor risk (PR). Only modest concordance between IGCCC and COG stratification systems was noted (49%). Nonetheless, the IGCCC identified a group of PR patients who had significantly worse event-free survival (EFS) versus GR/IR patients (6-year EFS 80% vs. 91%), which was similar to the difference observed using the COG system (6-year EFS 77% vs. 90%). The IGCCC performed well within subgroups for which the IGCCC is not intended (prepubertal, female, and non-metastatic patients).

CONCLUSIONS

Applying the IGCCC system to pediatric patients produces a different stratification than does the application of the COG system, although both are prognostic. Development of a de novo pediatric prognostic classification is warranted.

Patterns and determinants of physical activity in U.S. adolescents

PURPOSE

The objectives of this study were to describe longitudinal trends in adolescent physical activity in a sample of U.S. adolescents and to assess the effect of multiple individual, parental, and environmental factors on initial level and rates of change in adolescent physical activity.

METHODS

Study subjects were 12,812 boys and girls 10 to 18 years of age who were participating in the Growing Up Today Study and their mothers. We used accelerated longitudinal analysis to describe trajectories of physical activity from 1997-1999, and random effects linear mixed models to determine which factors were independently associated with baseline physical activity and changes in physical activity over time.

RESULTS

Mean hours of physical activity ranged from 7.3-11.6 hours per week in boys and from 8.0-11.2 hours per week in girls. Physical activity was best modeled as a quadratic function of age, increasing until early adolescence and declining after age 13 in boys and girls. Multivariable modeling demonstrated that variables associated with physical activity level at baseline in boys and girls were age, body mass index, psychosocial variables, personal attitudes about body shape, perceived peer attitudes about body shape/fitness, parental attitudes about physical activity, parental physical activity, and environmental barriers to physical activity. Age was the only factor that predicted change in physical activity over time.

CONCLUSIONS

Interventions to increase physical activity in adolescents should begin before adolescence. Interventions may be more effective if they are multimodal and focus on modifiable individual, parental, and environmental factors.

Household smoking restrictions and adolescent smoking

PURPOSE

To examine the association between household smoking restrictions and adolescent smoking, controlling for parental smoking, peer smoking, and tobacco marketing.

DESIGN

Cross-sectional analysis of 1999 data from the Growing Up Today Study, a longitudinal cohort of adolescents.

SETTING

Self-report questionnaire.

SUBJECTS

10,593 adolescents aged 12 to 18 years.

MEASURES

The dependent variable was established smoking (smoking > or = 100 cigarettes). Variables of interest were household smoking restrictions, parental smoking, peer smoking, and tobacco promotional item (TPI) possession.

RESULTS

Four percent of participants reported that their households permitted smoking. Parental smoking, peer smoking, and TPI possession were significantly associated with established smoking In logistic regression models adjusted for age, gender, peer smoking, and TPI possession, adolescent smoking was inversely related to the presence of a restrictive household policy (odds ratio [OR] = 0.67, 95% confidence interval [CI] = 0.48-0.93); however, when parental smoking was added to this model, the association was attenuated (OR = 0.94, CI = 0.65-1.35). When only one parent in the household smoked, smoking restrictions were more common when this parent was the father.

CONCLUSIONS

Although household smoking restrictions offer health benefits, they do not appear to be associated with adolescent smoking after accounting for other factors. Prior studies did not include parental smoking, peer smoking, and marketing influences. This analytic difference may explain apparent contradictions in the literature.

Milk consumption and the prepubertal somatotropic axis

BACKGROUND

Nutrients, hormones and growth factors in dairy foods may stimulate growth hormone (GH), insulin-like growth factor I (IGF-I), and raise the ratio of IGF-I to its binding protein, IGFBP-3. We conducted pilot studies in Mongolia and Massachusetts to test the extent to which milk intake raised somatotropic hormone concentrations in prepubertal children.

METHODS

In Ulaanbaatar, we compared plasma levels before and after introducing 710 ml daily whole milk for a month among 46 10-11 year old schoolchildren. In a randomized cross-over study in Boston, we compared plasma hormone levels of 28 6-8 year old girls after one week of drinking 710 ml low fat (2%) milk with their hormone levels after one week of consuming a macronutrient substitute for milk.

RESULTS

After a month of drinking whole milk, Mongolian children had higher mean plasma levels of IGF-I (p < 0.0001), IGF-I/IGFBP-3 (p < 0.0001), and 75th percentile of GH levels (p = 0.005). After a week of drinking low fat milk, Boston girls had small and non-significant increases in IGF-1, IGF-1/IGFBP-3 and GH.

CONCLUSION

Milk drinking may cause increases in somatotropic hormone levels of prepubertal girls and boys. The finding that milk intake may raise GH levels is novel, and suggests that nutrients or bioactive factors in milk may stimulate endogenous GH production.

Longitudinal relationship between television viewing and leisure-time physical activity during adolescence

OBJECTIVE

The goal was to examine the longitudinal associations of changes in television viewing and other sources of sedentary behavior with changes in leisure-time moderate/vigorous physical activity in adolescence.

METHODS

We studied a cohort of 6369 girls and 4487 boys who were 10 to 15 years of age in 1997. During each of 4 years of follow-up assessments, participants self-reported their weekly hours of television viewing. By using a seasonal questionnaire, we also obtained detailed information on physical activities over the previous year, from which we calculated total leisure-time moderate/vigorous physical activity. We performed linear regression analyses to assess the longitudinal associations between 1-year changes in television viewing and 1-year changes in leisure-time moderate/vigorous physical activity during the same year, using data from 1997 through 2001.

RESULTS

One-year changes (mean +/- SD) were -0.13 +/- 7.2 hours/week for leisure-time moderate/vigorous physical activity, -0.55 +/- 7.0 hours/week for television viewing, and -1.02 +/- 11.0 hours/week for total sedentary behaviors. In longitudinal models adjusted for age, age2, gender, race/ethnicity, Tanner stage, menarche (in girls), baseline physical activity, and baseline television viewing, we found no substantive relationship between year-to-year changes in television viewing and changes in leisure-time moderate/vigorous physical activity (0.03 hours/week, for each 1-hour/week change in television viewing). There were no material associations in age or gender subgroups.

CONCLUSIONS

In this longitudinal study, changes in television viewing were not associated with changes in leisure-time moderate/vigorous physical activity. Our findings suggest that television viewing and leisure-time physical activity are separate constructs, not functional opposites.

Frequent tanning bed use, weight concerns, and other health risk behaviors in adolescent females (United States)

OBJECTIVE

To examine the association between tanning bed use and weight concerns, health risk behaviors, and peer influence.

METHODS

The Growing Up Today Study (GUTS) is an ongoing prospective cohort study of adolescents established in 1996. In 1999, a total of 6,373 adolescent females ages 12-18 (offspring of participants in the Nurses Health Study 2) completed the survey.

RESULTS

Almost nine percent (8.6%) of the adolescent girls had used a tanning bed 1-9 times and an additional 5.4% had used tanning beds at least 10 times in the past year (frequent users). Logistic regression models revealed that frequent tanning bed use was associated with being highly concerned about weight (OR = 1.5, 95%CI = 1.1, 2.0), frequently dieting to lose weight (OR = 1.5, 95%CI = 1.1, 2.0), using laxatives or vomiting to control weight (OR = 3.6; 95%CI = 2.2-5.8), having friends who placed a lot of importance on being thin (OR = 2.6; 95%CI = 1.3-5.1), smoking cigarettes (OR=1.7, 95%CI = 1.1, 2.6), binge drinking (OR = 2.1, 95%CI = 1.3, 3.1), using recreational drugs (OR = 3.0; 95%CI = 2.4, 3.8), and trying to look like females in the media (sometimes/pretty much: OR = 1.3, 95%CI = 1.0, 1.8).

CONCLUSION

Frequent tanning bed use among adolescent females is associated with a range of health risk behaviors. This effect may be mediated by peer influence and a desire to look like other females in the media. Multi-pronged approaches, particularly those that target attitudes of young females, are needed to combat increased use of tanning beds.

Prognostic factors in children with extragonadal malignant germ cell tumors: a pediatric intergroup study

PURPOSE

To investigate prognostic factors for pediatric extragonadal malignant germ cell tumors (PEMGCT).

MATERIALS AND METHODS

Between 1990 and 1996, patients with stage I through IV PEMGCT were eligible for a trial of cisplatin dose intensity. We retrospectively investigated prognostic factors for PEMGCT, including age, stage, primary site, treatment, and elevated alfa fetoprotein by univariate and multivariate analysis.

RESULTS

The 165 patients had a median age of 1.9 years (range, 3 days to 18.5 years); 109 were female; and 99 had alfa fetoprotein > or = 10,000. There were 30 stage I/II, 61 stage III, and 74 stage IV tumors; primary sites included 88 sacrococcygeal, 39 thoracic, and 38 others. The 5-year overall survival (OS) and event-free survival (EFS) rates with standard deviations were 83.4% +/- 3.7% and 79.0% +/- 4.1%, respectively. Univariate analysis identified age > or = 12 years as a highly significant prognostic factor for EFS (5-year EFS, 48.9% +/- 15.6% v 84.1% +/- 3.9%; P < .0001) and for OS (5-year OS, 53.7% +/- 14.9% v 88.5% +/- 3.4%; P < .0001), whereas treatment was of borderline significance (P = .0777). Multivariate Cox proportional hazards regression identified only age > or = 12 years as a significant prognostic factor for EFS (P = .0002). In multivariate Cox regression for OS, the combination of age and primary site was highly significant (P < .0001). Patients > or = 12 years of age with thoracic tumors had six times the risk of death compared with patients younger than 12 years with other primaries.

CONCLUSION

Age is the most predictive factor of EFS in PEMGCT. There is a significant interaction between age and primary site, suggesting that patients > or = 12 years of age with thoracic tumors are a biologically distinct group.

Prognostic factors in children with extragonadal malignant germ cell tumors: a pediatric intergroup study

PURPOSE

To investigate prognostic factors for pediatric extragonadal malignant germ cell tumors (PEMGCT).

MATERIALS AND METHODS

Between 1990 and 1996, patients with stage I through IV PEMGCT were eligible for a trial of cisplatin dose intensity. We retrospectively investigated prognostic factors for PEMGCT, including age, stage, primary site, treatment, and elevated alfa fetoprotein by univariate and multivariate analysis.

RESULTS

The 165 patients had a median age of 1.9 years (range, 3 days to 18.5 years); 109 were female; and 99 had alfa fetoprotein > or = 10,000. There were 30 stage I/II, 61 stage III, and 74 stage IV tumors; primary sites included 88 sacrococcygeal, 39 thoracic, and 38 others. The 5-year overall survival (OS) and event-free survival (EFS) rates with standard deviations were 83.4% +/- 3.7% and 79.0% +/- 4.1%, respectively. Univariate analysis identified age > or = 12 years as a highly significant prognostic factor for EFS (5-year EFS, 48.9% +/- 15.6% v 84.1% +/- 3.9%; P < .0001) and for OS (5-year OS, 53.7% +/- 14.9% v 88.5% +/- 3.4%; P < .0001), whereas treatment was of borderline significance (P = .0777). Multivariate Cox proportional hazards regression identified only age > or = 12 years as a significant prognostic factor for EFS (P = .0002). In multivariate Cox regression for OS, the combination of age and primary site was highly significant (P < .0001). Patients > or = 12 years of age with thoracic tumors had six times the risk of death compared with patients younger than 12 years with other primaries.

CONCLUSION

Age is the most predictive factor of EFS in PEMGCT. There is a significant interaction between age and primary site, suggesting that patients > or = 12 years of age with thoracic tumors are a biologically distinct group.

Sun protection practices among offspring of women with personal or family history of skin cancer

OBJECTIVE

Family history of skin cancer is an important determinant of skin cancer risk for offspring. No previous study of the effect of personal or family history of skin cancer on the sun protection behaviors of the offspring has been published.

METHODS

A retrospective study was conducted of the sun protection behaviors of the adolescent participants in the Growing Up Today Study (GUTS), who were offspring of mothers from the Nurses Health Study II. Adolescents' surveys were matched with their mothers' reports of a personal or family history of skin cancer and compared with adolescents whose mothers did not report a personal or family history of skin cancer. The outcome measures were (1) occurrence of frequent sunburns during the past summer, (2) use of a tanning bed during the past year, and (3) routine use of sunscreen. Frequent sunburns were defined as the report of > or = 3 sunburns during the past summer. We compared those who reported having used a tanning bed in the past year at least once with those who reported no tanning bed use in the past year. Routine use of sunscreen was defined as a respondent who replied that he or she "always" or "often" used sunscreen with sun protection factor of 15 or more when he or she was outside for > 15 minutes on a sunny day during the past summer. General estimating equations were used to calculate odds ratios and 95% confidence intervals adjusted for gender, age, color of untanned skin, and number of friends who were tanned. We also conducted an additional analysis restricted to children whose mothers had received a diagnosis of skin cancer in which we assessed sun protection behaviors according to the child's age and mother's age at the time of the mother's diagnosis and the number of years that had passed since the diagnosis of the mother's skin cancer.

RESULTS

In 1999, 9943 children reported their sun protection behaviors; 8697 of their mothers had not received a diagnosis of skin cancer or reported a family history of melanoma, 463 participants' mothers had received a diagnosis of skin cancer, and 783 participants' mothers reported a family history of melanoma. Between 1989 and 1999, 371 mothers of GUTS participants received a diagnosis of skin cancer: melanoma (n = 44), squamous cell (n = 39), and basal cell cancer (n = 311); 23 mothers received a diagnosis of > 1 type of skin cancer. Because GUTS includes siblings from the same family, the 371 mothers with skin cancer had 463 offspring in GUTS. Offspring of mothers with skin cancer were slightly more likely to report frequent sunburns in the past year compared with those with neither maternal diagnosis nor family history (39% vs 36%). Tanning bed use was not significantly different among those with either a maternal diagnosis of skin cancer or family history of melanoma as compared with nonaffected adolescents (8% vs 9% vs 10%). Sunscreen use among offspring of mothers with skin cancer was higher than among those whose mothers had a family history of melanoma or mothers with no personal history of skin cancer (42% vs 33% vs 34%). Tan-promoting attitudes were also similar across all groups. Only 25% thought that a natural skin color was most attractive, and on average, 25% in each group agreed that it was worth burning to get a tan. Children of mothers who had received a diagnosis > 2 years in the past were less likely to use sunscreen, more likely to sunburn, and more likely to use tanning beds than children of mothers with a more recent diagnosis, although the results did not reach statistical significance.

CONCLUSION

Frequent sunburns, suboptimal sunscreen use, and high rates of tanning bed use are commonplace even among the children of health professionals who are at risk for developing skin cancer themselves as a result of personal or family history. With new information on family risk, pediatricians can use the potential of a teachable moment to ensure optimal sun protection for children who are at risk.

Breast-feeding and overweight in adolescence: within-family analysis [corrected]

BACKGROUND

Previous reports have found associations between having been breast-fed and a reduced risk of being overweight. These associations may be confounded by sociocultural determinants of both breast-feeding and obesity. We addressed this possibility by assessing the association of breast-feeding duration with adolescent obesity within sibling sets.

METHODS

We surveyed 5,614 siblings age 9 to 14 years and their mothers. These children were a subset of participants in the Growing Up Today Study, in which we had previously reported an inverse association of breast-feeding duration with overweight. We compared the prevalence of overweight (body mass index exceeding the age-sex-specific 85th percentile) in siblings who were breast-fed longer than the mean duration of their sibship with those who were breast-fed for a shorter period. Then we compared odds ratios from this within-family analysis with odds ratios from an overall (ie, not within-family) analysis.

RESULTS

Mean +/- standard deviation breast-feeding duration was 6.4 +/- 4.0 months, and crude prevalence of overweight was 19%. On average, siblings who were breast-fed longer than their family mean had breast-feeding duration 3.7 months longer than their shorter-duration siblings. The adjusted odds ratio (OR) for overweight among siblings with longer breast-feeding duration, compared with shorter duration, was 0.92 (95% confidence interval = 0.76-1.11). In overall analyses, the adjusted OR was 0.94 (0.88-1.00) for each 3.7-month increment in breast-feeding duration.

CONCLUSION

The estimated OR for the within-family analysis was close to the overall estimate, suggesting that the apparent protective effect of breast-feeding on later obesity was not highly confounded by unmeasured sociocultural factors. A larger study of siblings, however, would be needed to confirm this conclusion.

Amifostine does not protect against the ototoxicity of high-dose cisplatin combined with etoposide and bleomycin in pediatric germ-cell tumors: a Children's Oncology Group study

BACKGROUND

High-dose cisplatin combined with etoposide and bleomycin (HDPEB) improves event-free survival (EFS) in advanced pediatric germ-cell tumors (PGCT), but has significant ototoxicity. Amifostine appears to protect against toxicity. The authors combined amifostine with HDPEB and evaluated the efficacy and toxicity, specifically whether ototoxicity decreased.

METHODS

Eligibility criteria included age < 15 years and unresectable Stage III/IV extracranial, extragonadal PGCT. Patients received bleomycin 15 IU/m(2) on Day 1, then etoposide 100 mg/m(2) per day, amifostine 825 mg/m(2) per day, and cisplatin 40 mg/m(2)per day on Days 1-5, intravenously. The cycles were repeated every 3-4 weeks with imaging evaluation after 4 cycles. Patients with residual radiographic abnormalities underwent resection. Patients with residual tumor received two additional HDPEB cycles. Hearing evaluations were required at diagnosis and after two and four cycles. Audiologic results were reviewed and compared with historical controls treated with HDPEB.

RESULTS

Twenty-five eligible patients were enrolled between April 2000 and April 2002. Their median age was 1.6 years (range, 0.64-13.9 years), 17 patients were female, 11 had metastases, and 24 had a yolk sac carcinoma component histologically. Primary sites included sacrococcygeal area/pelvis (n = 15), vagina (n = 5), and other (n = 5). Two-year EFS and overall survival were 83.5% +/- 12.8% and 85.6% +/- 12.3%, respectively. Eight patients were removed from the study (four had progressive disease/disease recurrence and four had ototoxicity). Grade 3/4 toxicities included neutropenia (n = 20), thrombocytopenia (n = 14), electrolyte imbalances (n = 14), and gastrointestinal toxicity (n = 12). Twenty-four of 25 patients received hearing evaluations, and 75% had significant hearing loss.

CONCLUSIONS

Amifostine did not protect against HDPEB-associated ototoxicity.

Family dinner and adolescent overweight

OBJECTIVE

The purpose of this study was to examine both cross-sectional and longitudinal associations between frequency of family dinner and overweight status in a large sample of 9- to 14-year-old children.

RESEARCH METHODS AND PROCEDURES

We studied a cohort of 7784 girls and 6647 boys, 9 to 14 years of age at baseline in 1996, participating in the Growing Up Today Study. From annual mailed surveys, we calculated BMI from self-reported height and weight and assessed frequency of family dinner over the previous year. We defined "overweight" as age- and sex-specific BMI >85th percentile. We performed multiple logistic regression analyses; the longitudinal analyses assessed the association of previous year family dinner consumption with 1-year incidence of becoming overweight, using prospective data from 1996 through 1999.

RESULTS

At baseline in 1996, 16% of participants had family dinner "never or some days," 40% on "most days," and 44% "every day." Across these categories, overweight prevalence for girls was 19.4%, 16.6%, and 16.7% and for boys was 24.6%, 23.3%, and 22.7%, respectively. In cross-sectional analyses, adjusting for potential confounders, the odds of being overweight was 0.85 [95% confidence interval (CI): 0.76, 0.96] among children who ate family dinner on "most days" or "every day" compared with those who ate family dinner "never or some days." In longitudinal multivariate models, the odds ratios between previous year frequency of eating family dinner and 1-year incidence of becoming overweight were 0.95 (95% CI: 0.78, 1.16) and 1.04 (95% CI: 0.85, 1.27) for children who ate family dinner on "most days" and "every day," respectively, compared with those who ate family dinner "never or some days."

DISCUSSION

The frequency of eating family dinner was inversely associated with overweight prevalence at baseline but not with likelihood of becoming overweight in longitudinal analyses.

High school dietary dairy intake and teenage acne

BACKGROUND

Previous studies suggest possible associations between Western diet and acne. We examined data from the Nurses Health Study II to retrospectively evaluate whether intakes of dairy foods during high school were associated with physician-diagnosed severe teenage acne.

METHODS

We studied 47,355 women who completed questionnaires on high school diet in 1998 and physician-diagnosed severe teenage acne in 1989. We estimated the prevalence ratios and 95% confidence intervals of acne history across categories of intakes.

RESULTS

After accounting for age, age at menarche, body mass index, and energy intake, the multivariate prevalence ratio (95% confidence intervals; P value for test of trend) of acne, comparing extreme categories of intake, were: 1.22 (1.03, 1.44; .002) for total milk; 1.12 (1.00, 1.25; .56) for whole milk; 1.16 (1.01, 1.34; .25) for low-fat milk; and 1.44 (1.21, 1.72; .003) for skim milk. Instant breakfast drink, sherbet, cottage cheese, and cream cheese were also positively associated with acne.

CONCLUSION

We found a positive association with acne for intake of total milk and skim milk. We hypothesize that the association with milk may be because of the presence of hormones and bioactive molecules in milk.

Adult recall of adolescent diet: reproducibility and comparison with maternal reporting

Many cancers have long latency periods, and dietary factors in adolescence may plausibly affect cancer occurrence in adulthood. Because of a lack of prospective data, retrospective collection of data on adolescent diet is essential. The authors evaluated a 124-item high school food frequency questionnaire (HS-FFQ) assessing diet during high school (15-35 years in the past) that was completed in 1998 by 45,947 US women in the Nurses' Health Study II (NHSII) cohort. To assess reproducibility, the authors readministered the HS-FFQ approximately 4 years later to 333 of these women. The mean Pearson correlation for 38 nutrient intakes was 0.65 (range, 0.50-0.77), and the mean Spearman rank correlation for food intakes was 0.60 (range, 0.37-0.77). Current adult diet was only weakly correlated with recalled adolescent diet (for nutrient intakes, mean r = 0.20). For assessment of validity, 272 mothers of the NHSII participants were asked to report information on their daughters' adolescent diets using the HS-FFQ. In this comparison, the mean Pearson correlation was 0.40 (range, 0.13-0.59) for nutrients, and the mean Spearman rank correlation for foods was 0.30 (range, 0.10-0.61). While further studies are warranted, these findings imply that this food frequency questionnaire provides a reasonable record of adolescent diet.

State tobacco excise taxes and adolescent smoking behaviors in the United States

The objective of the study described in this article was to examine the association between state cigarette excise taxes and smoking behaviors among youth in the United States. A survey was nationally mailed to adolescents in the Growing Up Today Study, an ongoing cohort of offspring of participants in the Nurses' Health Study II. A volunteer sample of 10,981 adolescent boy and girl participated in the Growing Up Today Study, who were 12 to 18 years old in 1999. Logistic regression was used to examine the relationship between state cigarette excise taxes (in quartiles) and experimentation (ever smoked) and established smoking (smoked at least 100 cigarettes in a lifetime). State tax levels in 1999 ranged from 2.5 to 100 cents. In a model that adjusted for age, gender, peer smoking, parental smoking, state clustering, state poverty level, and possession of tobacco promotional items, higher tax rates were associated with decreased odds of experimentation (test for trend p < 0.01). The highest quartile of tax (60-100 cents) was significantly associated with lower odds of experimentation (OR = 0.79; 95% CI, 0.64-0.98) and appeared protective against established smoking (OR = 0.80; 95% CI, 0.49-1.29). This study provides recent evidence that higher state cigarette excise taxes are associated with decreased experimental smoking among adolescent boys and girls. Higher state cigarette taxes may also be associated with lower odds of established smoking in this age group, although the association appears to be attenuated by peer and parental smoking. These results support the inclusion of tobacco taxes in state tobacco control programs.

Development of a scale to measure adolescents' beliefs and attitudes about postponing sexual initiation

PURPOSE

To develop a scale to measure adolescent beliefs and attitudes about postponing sexual initiation (PSI).

METHODS

A theory-based, 12-item scale measuring beliefs about PSI was developed and administered via a mailed questionnaire to those participants in an ongoing longitudinal cohort study of adolescents who had not yet initiated sexual intercourse. Internal consistency reliability, content validity, factorial validity, and construct validity were assessed using cross-sectional data.

RESULTS

Mean age for boys was 14.4 (+/- 1.6) years and for girls 14.3 (+/-1.6) years (range 11 to 19 years), and 93% of respondents were white. The beliefs about PSI rated as most important by both girls and boys were concern about pregnancy and sexually transmitted infection. Cronbach alpha for the scale was 0.83 for girls and 0.88 for boys. Exploratory factor analysis demonstrated that the items loaded on four factors consistent with the theoretical basis of the model and confirmatory factor analysis demonstrated good fit of the overall model. The PSI scale score was associated with hypothesized sociodemographic, psychological, and behavioral variables, supporting construct validity of the scale. A higher score was associated with female gender; age < or = 14 years; higher global and social self-esteem; more frequent attendance at religious services; less peer pressure to have sexual intercourse; nonuse of alcohol, illicit drugs, and cigarettes; and no intention to initiate sexual intercourse in the next year.

CONCLUSIONS

The PSI scale demonstrated satisfactory psychometric properties. Future research is needed to evaluate the utility of this scale in predicting sexual initiation and in interventions aimed at postponing sexual initiation.

The influence of wanting to look like media figures on adolescent physical activity

PURPOSE

To examine the association of adolescents' wanting to look like figures in the media with physical activity levels.

METHODS

Cross-sectional mailed survey of 11,606 boys and girls, between the ages of 9 and 16 years, participating in the Growing Up Today Study in 1997. Participants reported detailed information on physical activities over the previous year, and the degree to which they were trying to look like same-sex images in television, movies, and magazines. We performed linear regression modeling to assess the independent effects of wanting to look like figures in the media on physical activity levels.

RESULTS

Mean total weekly physical activity levels were 12.4 hours in girls and 15.2 hours in boys. 3019 (46%) girls and 1360 (27%) boys reported making at least some effort to look like figures in the media. Adjusted for age, body mass index, sexual maturity rating, and race/ethnicity, total physical activity levels were higher by 0.7 (95% CI 0.5-0.9) and 1.2 (95% CI 0.9-1.6) hours per week in girls and boys, respectively, for every 1 (out of 5) category increase in wanting to look like figures in the media. Adjustment for intrapersonal and social confounders modestly attenuated the associations.

CONCLUSIONS

Wanting to look like figures in the media was associated with higher physical activity levels among older children and adolescents, independent of other personal and social influences. These data suggest that television, movie, and magazine industries should be encouraged to cultivate and reinforce realistic and healthy norms of physical activity and body image.

Sexual orientation and tobacco use in a cohort study of US adolescent girls and boys

OBJECTIVE

To examine sexual-orientation group disparities in tobacco use in adolescent girls and boys.

DESIGN

Survey data from 10685 adolescent girls and boys participating in 1999 in the Growing Up Today Study were examined cross-sectionally.

SETTING

Community-based population of adolescents living throughout the United States. Main Outcome Measure Prevalence of tobacco use.

RESULTS

Ninety-two percent of the participants described themselves as heterosexual (n = 9296), 5% as mostly heterosexual (n = 511), 1% as lesbian/gay/bisexual (n = 103), and 2% as unsure (n = 226). Ages ranged from 12 to 17 years. Compared with heterosexuals, mostly heterosexual girls were 2.5 (95% confidence interval, 1.8-3.5), lesbian/bisexual girls were 9.7 (95% confidence interval, 5.1-18.4), and mostly heterosexual boys were 2.5 (95% confidence interval, 1.4-4.6) times more likely to smoke at least weekly. In contrast, gay/bisexual boys were not more likely to smoke. Findings persisted even when controlling for multiple sociodemographic and psychosocial covariates.

CONCLUSION

Our findings indicate that mostly heterosexual adolescents of both sexes and lesbian/bisexual girls are at heightened risk for tobacco use.

Adolescent diet and risk of breast cancer

OBJECTIVES

To investigate the components of adolescent diet that may influence risk of breast cancer as an adult.

METHODS

Retrospective cohort study among 47,355 participants in the Nurses Health Study II who answered a 131-item food frequency questionnaire about diet during high school. Cox proportional hazards regression was used to estimate relative risks and 95% confidence intervals among incident cases of breast cancer between 1989 (inception of the study) and 1998 (when high school diet was assessed).

RESULTS

Intakes of fat and fiber were not significantly related to risk of breast cancer in multivariate analysis, but increased intake of vegetable fat ( Q (5) versus Q (1) multivariate RR = 0.58, 95% CI (0.38-0.86); test for trend p = 0.005) and vitamin E ( Q (5) versus Q (1) multivariate RR = 0.61, 95% CI (0.42-0.89); test for trend p = 0.003) were associated with a lower risk. A higher dietary glycemic index ( Q (5) versus Q (1) multivariate RR = 1.47, 95% CI (1.04-2.08); test for trend p = 0.01) was associated with increased risk of breast cancer.

CONCLUSIONS

The apparent protective effects of vegetable fat and vitamin E and adverse effect of high glycemic foods on risk of breast cancer need confirmation in prospective analyses.

Adolescent diet and risk of breast cancer

BACKGROUND

Early life exposures, including diet, have been implicated in the etiology of breast cancer.

METHODS

A nested case-control study was conducted among participants in the Nurses' Health Study who completed a 24-item questionnaire about diet during high school. There were 843 eligible cases diagnosed between onset of study (1976) and before the return of the high school diet questionnaire (1986), who were matched 10:1 with controls on the basis of age.

RESULTS

Women who had, during adolescence, a higher consumption of eggs, vegetable fat and fiber had a lower risk of breast cancer, whereas risk of breast cancer was increased among women who consumed more butter.

CONCLUSIONS

A possible association of elements of adolescent diet with risk of breast cancer is reported, but the findings require confirmation in prospective study.

Smoking, getting drunk, and engaging in bulimic behaviors: in which order are the behaviors adopted?

OBJECTIVE

To assess the relation between beginning to binge-eat or purge, beginning to smoke, and getting drunk for the first time.

METHOD

Prospective study of 11,358 girls and boys, 10 to 15 years of age, in an ongoing cohort study who completed questionnaires in 1997 and 1998. The outcome measures were beginning to engage in bulimic behaviors, beginning to smoke, and getting drunk for the first time between 1997 and 1998.

RESULTS

During 1 year, 4.3% of girls and 3.8% of boys started smoking, 5.3% of girls and 4.8% of boys started getting drunk, and 2.4% of girls and 0.8% of boys started engaging in bulimic behaviors. Among the girls, weight concerns in 1997 were predictive of beginning to smoke (odds ratio [OR] = 2.2), get drunk (OR = 1.7), purge (OR = 3.8), and binge-eat (OR = 2.6). Adolescents who reported smoking in 1997 were more likely than nonsmokers to get drunk for the first time (girls: OR = 5.7; boys: OR = 7.1). The reverse association, getting drunk as a predictor of starting to smoke, was of lesser magnitude (OR = 2.3-2.6).

CONCLUSIONS

The three unhealthy behaviors were associated prospectively with each other. The results suggest that prevention efforts should target weight concerns and multiple risk behaviors.

Use of sunscreen, sunburning rates, and tanning bed use among more than 10 000 US children and adolescents

OBJECTIVES

To describe the association of sunscreen use, sunburning, and tanning bed use by age, sex, residence, and psychosocial variables associated with tan-seeking behaviors, and to compare these findings with sun protection recommendations from federal agencies and cancer organizations.

METHODS

A cross-sectional study, from all 50 states, of 10 079 boys and girls 12 to 18 years of age in 1999. Data were collected from self-report questionnaires with the children of the participants from the Nurses Health Study (Growing Up Today Study).

RESULTS

The prevalence of sunscreen use was 34.4% with girls more likely to use sunscreen than boys (40.0 vs 26.4, odds ratio: 1.86; 95% confidence interval: 1.70-2.03). Eighty-three percent of respondents had at least 1 sunburn during the previous summer, and 36% had 3 or more sunburns. Nearly 10% of respondents used a tanning bed during the previous year. Girls were far more likely than boys to report tanning bed use (14.4 vs 2.4), and older girls (ages 15-18) were far more likely than younger girls (ages 12-14) to report tanning bed use (24.6% vs 4.7). Tanning bed use increased from 7% among 14-year-old girls to 16% by age 15, and more than doubled again by age 17 (35%; N = 244). Multivariate analysis demonstrated that attitudes associated with tanning, such as the preference for tanned skin, having many friends who were tanned, and belief in the worth of burning to get a tan, were generally associated with sporadic sunscreen use, more frequent sunburns, and increased use of tanning beds.

CONCLUSIONS

Our findings suggest that many children are at subsequent risk of skin cancer because of suboptimal sunscreen use, high rates of sunburning, and tanning bed use. Recommendations in the United States for improved sun protection and avoidance of tanning beds and sunburning, which began in the early 1990s, have been primarily unheeded. Nationally coordinated campaigns with strong policy components must be developed and sustained to prevent skin cancer in a new generation of children and adolescents.

Prevalence and correlates of pelvic examinations in sexually active female adolescents

OBJECTIVES

The pelvic examination is an important component of reproductive health services for adolescent girls and is recommended for those who become sexually active. The aims of this study were to describe self-reported rates of pelvic examinations in sexually active adolescent girls and to determine factors associated with having obtained an examination.

METHODS

Cross-sectional data from a national self-administered survey of nurses' adolescent daughters were used. Subjects were those girls (N = 635) who reported ever having had sexual intercourse. Bivariate and multivariate analyses were used to identify demographic and psychological variables, preventive health behaviors, and risk behaviors associated with having ever obtained a pelvic examination.

RESULTS

Median subject age was 16.0 years (range 12-19 years), and 46% of subjects reported having had a pelvic examination. Variables associated with having obtained an examination were older age (odds ratio [OR] 1.29, 95% confidence interval [CI] 1.09-1.53), cigarette smoking (OR 1.51, 95% CI 1.02-2.24), higher number of sexual partners (OR 1.29, 95% CI 1.14-1.47), and no condom use during last sexual intercourse (OR 1.80, 95% CI 1.19-2.70).

CONCLUSIONS

Fewer than half of these sexually active adolescents had ever obtained a pelvic examination. Younger subjects who did not smoke regularly, had fewer partners, and used condoms were less likely to have obtained an examination; these adolescents may not be seeking reproductive health care services or be recognized by parents or providers as being in need of services.

Adolescents' perceptions of social status: development and evaluation of a new indicator

OBJECTIVE

Eliminating health disparities, including those that are a result of socioeconomic status (SES), is one of the overarching goals of Healthy People 2010. This article reports on the development of a new, adolescent-specific measure of subjective social status (SSS) and on initial exploratory analyses of the relationship of SSS to adolescents' physical and psychological health.

METHODS

A cross-sectional study of 10 843 adolescents and a subsample of 166 paired adolescent/mother dyads who participated in the Growing Up Today Study was conducted. The newly developed MacArthur Scale of Subjective Social Status (10-point scale) was used to measure SSS. Paternal education was the measure of SES. Indicators of psychological and physical health included depressive symptoms and obesity, respectively. Linear regression analyses determined the association of SSS to depressive symptoms, and logistic regression determined the association of SSS to overweight and obesity, controlling for sociodemographic factors and SES.

RESULTS

Mean society ladder ranking, a subjective measure of SES, was 7.2 +/- 1.3. Mean community ladder ranking, a measure of perceived placement in the school community, was 7.6 +/- 1.7. Reliability of the instrument was excellent: the intraclass correlation coefficient was 0.73 for the society ladder and 0.79 for the community ladder. Adolescents had higher society ladder rankings than their mothers (micro(teen) = 7.2 +/- 1.3 vs micro(mom) = 6.8 +/- 1.2; P =.002). Older adolescents' perceptions of familial placement in society were more closely correlated with maternal subjective perceptions of placement than those of younger adolescents (Spearman's rho(teens <15 years) = 0.31 vs Spearman's rho(teens 15 years) = 0.45; P <.001 for both). SSS explained 9.9% of the variance in depressive symptoms and was independently associated with obesity (odds ratio(society) = 0.89, 95% confidence interval = 0.83, 0.95; odds ratio(community) = 0.91, 95% confidence interval = 0.87, 0.97). For both depressive symptoms and obesity, community ladder rankings were more strongly associated with health than were society ladder rankings in models that controlled for both domains of SSS.

CONCLUSIONS

This new instrument can reliably measure SSS among adolescents. Social stratification as reflected by SSS is associated with adolescents' health. The findings suggest that as adolescents mature, SSS may undergo a developmental shift. Determining how these changes in SSS relate to health and how SSS functions prospectively with regard to health outcomes requires additional research.