The impact of a school-based obesity prevention trial on disordered weight-control behaviors in early adolescent girls

OBJECTIVE: To assess the impact of an obesity prevention intervention on use of self-induced vomiting/laxatives (purging) and diet pills to control weight in girls in early adolescence. DESIGN: We matched and randomly assigned 10 middle schools to an intervention or a control condition in a randomized controlled trial. Longitudinal multivariable analyses using generalized estimating equations were conducted with data from 480 girls to examine the effects of the intervention on the risk of reporting a new case of purging or diet pill use to control weight at follow-up 21 months later, while controlling for ethnicity and school matched pairs. Girls who reported purging or using diet pills at baseline were excluded from analyses. SETTING: Middle schools. PARTICIPANTS: Four hundred eighty girls in early adolescence aged 10 to 14 years (mean age, 11.5 years). INTERVENTION: The Planet Health obesity prevention program was implemented during 2 school years and was designed to promote healthful nutrition and physical activity and to reduce television viewing. OUTCOME: Reduced risk of using self-induced vomiting/laxatives or diet pills to control weight in the past 30 days. RESULTS: After the intervention, we found 14 (6.2%) of 226 girls in control schools and 7 (2.8%) of 254 girls in intervention schools reported purging or using diet pills to control their weight (P = .003). In a multivariable generalized estimating equation model, girls in intervention schools were less than half as likely to report purging or using diet pills at follow-up compared with girls in control schools (odds ratio, 0.41; 95% confidence interval, 0.22-0.75). CONCLUSION: These findings provide promising evidence that school-based interventions may effectively integrate prevention of both obesity and disordered weight-control behaviors.     

Reducing obesity via a school-based interdisciplinary intervention among youth: Planet Health

OBJECTIVE: To evaluate the impact of a school-based health behavior intervention known as Planet Health on obesity among boys and girls in grades 6 to 8. DESIGN: Randomized, controlled field trial with 5 intervention and 5 control schools. Outcomes were assessed using preintervention (fall 1995) and follow-up measures (spring 1997), including prevalence, incidence, and remission of obesity. PARTICIPANTS: A group of 1295 ethnically diverse grade 6 and 7 students from public schools in 4 Massachusetts communities. INTERVENTION: Students participated in a school-based interdisciplinary intervention over 2 school years. Planet Health sessions were included within existing curricula using classroom teachers in 4 major subjects and physical education. Sessions focused on decreasing television viewing, decreasing consumption of high-fat foods, increasing fruit and vegetable intake, and increasing moderate and vigorous physical activity. MAIN OUTCOME MEASURES: Obesity was defined as a composite indicator based on both a body mass index and a triceps skinfold value greater than or equal to age- and sex-specific 85th percentiles. Because schools were randomized, rather than students, the generalized estimating equation method was used to adjust for individual-level covariates under cluster randomization. RESULTS: The prevalence of obesity among girls in intervention schools was reduced compared with controls, controlling for baseline obesity (odds ratio, 0.47; 95% confidence interval, 0.24-0.93; P = .03), with no differences found among boys. There was greater remission of obesity among intervention girls vs. control girls (odds ratio, 2.16; 95% confidence interval, 1.07-4.35; P = .04). The intervention reduced television hours among both girls and boys, and increased fruit and vegetable consumption and resulted in a smaller increment in total energy intake among girls. Reductions in television viewing predicted obesity change and mediated the intervention effect. Among girls, each hour of reduction in television viewing predicted reduced obesity prevalence (odds ratio, 0.85; 95% confidence interval, 0.75-0.97; P = .02). CONCLUSION: Planet Health decreased obesity among female students, indicating a promising school-based approach to reducing obesity among youth.     

Weight-related concerns and behaviors among overweight and nonoverweight adolescents: implications for preventing weight-related disorders

OBJECTIVES: To assess weight-related concerns and behaviors in a population-based sample of adolescents and to compare these concerns and behaviors across sex and weight status. DESIGN: The study population included 4746 adolescents from St Paul or Minneapolis, Minn, public schools who completed surveys and anthropometric measurements as part of Project EAT (Eating Among Teens), a population-based study focusing on eating patterns and weight concerns among teenagers. MAIN OUTCOME MEASURES: Measured weight status, weight-related concerns (perceived weight status, weight disparity, body satisfaction, and care about controlling weight), and weight-related behaviors (general and specific weight control behaviors and binge eating). RESULTS: Weight-related concerns and behaviors were prevalent among the study population. Although adolescents were most likely to report healthy weight control behaviors (adolescent girls, 85%; and adolescent boys, 70%), also prevalent were weight control behaviors considered to be unhealthy (adolescent girls, 57%; and adolescent boys, 33%) or extreme (adolescent girls, 12%; and adolescent boys, 5%). Most overweight youth perceived themselves as overweight and reported the use of healthy weight control behaviors during the past year. However, the use of unhealthy and extreme weight control behaviors and binge eating were alarmingly high among overweight youth, particularly adolescent girls. Extreme weight control practices (taking diet pills, laxatives, or diuretics or vomiting) were reported by 18% of very overweight adolescent girls, compared with 6% of very overweight adolescent boys (body mass index, > OR = 95th percentile). CONCLUSION: Prevention interventions that address the broad spectrum of weight-related disorders, enhance skill development for behavioral change, and provide support for dealing with potentially harmful social norms are warranted in light of the high prevalence and co-occurrence of obesity and unhealthy weight-related behaviors.     

Effect of physical activity intervention on body composition in young children: influence of body mass index status and gender

AIM: To fight overweight and obesity in childhood, this study proposes an additional physical activity (PA) in young children aged 6-10 years. The objective was to evaluate the effect of school-based PA on the body composition according to body mass index (BMI) categories (nonobese vs. obese) and gender. METHODS: This 6-month study examined the effect of this intervention on body composition in 425 children in 14 primary schools (2 weekly PA sessions of 1 h each) compared to 5 control schools. Adiposity indices were evaluated or calculated: BMI, BMI z-score, waist circumference, sum of skinfolds and fat-free mass. RESULTS: No difference in the prevalence of obesity and anthropometric characteristics was found between the intervention and control groups at baseline. In girls, PA intervention had significant effect on all anthropometric variables (p < 0.05 to p < 0.001), except on BMI. In contrast, in boys only BMI z-score (p < 0.001) and fat-free mass (p < 0.001) were affected. CONCLUSIONS: Six months of preventive PA intervention offer an effective means to improve body composition in obese children. The pattern of response related to PA was similar between girls and boys. In contrast, the pattern was different according to BMI category, with a higher response in obese than nonobese children.     

Weight-related behaviors among adolescent girls and boys: results from a national survey

OBJECTIVE: The study objectives were to assess (1) the prevalence of dieting and disordered eating among adolescents; (2) the sociodemographic, anthropometric, psychosocial, and behavioral correlates of dieting and disordered eating; and (3) whether adolescents report having discussed weight-related issues with their health care providers. DESIGN: Cross-sectional school-based survey. STUDY POPULATION: A nationally representative sample of 6728 adolescents in grades 5 to 12 who completed the Commonwealth Fund surveys of the health of adolescent girls and boys. MAIN OUTCOME MEASURES: Dieting and disordered eating (binge-purge cycling). RESULTS: Approximately 24% of the population was overweight. Almost half of the girls (45%) reported that they had at some point been on a diet, compared with 20% of the boys. Disordered eating was reported by 13% of the girls and 7% of the boys. Strong correlates of these behaviors included overweight status, low self-esteem, depression, suicidal ideation, and substance use. Almost half of the adolescents (38%-53%) reported that a health care provider had at some point discussed nutrition or weight with them. Discussions on eating disorders were reported by lower percentages of girls (24%) and boys (15%). CONCLUSIONS: The high prevalence of weight-related concerns suggests that all youth should be reached with appropriate interventions. Special attention needs to be directed toward youth at greatest risk for disordered eating behaviors, such as overweight youth, youth engaging in substance use behaviors, and youth with psychological concerns such as low self-esteem and depressive symptoms.     

Randomised controlled trial adapting US school obesity prevention to England.

OBJECTIVES: To determine whether a school obesity prevention project developed in the United States can be adapted for use in England. METHODS: A pilot cluster randomised controlled trial and interviews with teachers were carried out in 19 primary schools in South West England. Participants included 679 children in year 5 (age 9-10). Baseline and follow-up assessments were completed for 323 children (screen viewing) and 472 children (body mass index). Sixteen lessons on healthy eating, physical activity and reducing TV viewing were taught over 5 months by teachers. Main outcome measures were hours of screen activities, body mass index, mode of transport to school and teachers' views of the intervention. RESULTS: Children from intervention schools spent less time on screen-viewing activities after the intervention but these differences were imprecisely estimated: mean difference in minutes spent on screen viewing at the end of the intervention (intervention schools minus control schools) adjusted for baseline levels and clustering within schools was -11.6 (95% CI -42.7 to 19.4) for a week day and was -15.4 (95% CI -57.5 to 26.8) for a Saturday. There was no difference in mean body mass index or the odds of obesity. CONCLUSIONS: It is feasible to transfer this US school-based intervention to UK schools, and it may be effective in reducing the time children spend on screen-based activities. The study has provided information for a full-scale trial, which would require 50 schools ( approximately 1250 pupils) to detect effects on screen viewing and body mass index over 2 years of follow-up.     

A longitudinal evaluation of adolescent depression and adult obesity

BACKGROUND: Prior studies have had conflicting results regarding the relationship between adolescent depression and adult obesity. OBJECTIVE: To test the hypothesis that depression in adolescence would increase the risk for obesity in early adulthood. METHODS: We used data from a longitudinal study of a birth cohort of children born between April 1, 1972, and March 31, 1973, in Dunedin, New Zealand (N = 1037). These data included regular diagnostic mental health interviews and height/weight measurements throughout childhood and adolescence. We performed logistic regression analyses to assess the relationship between major depression in early or late adolescence and the risk for obesity at 26 years of age. RESULTS: Major depression occurred in 7% of the cohort during early adolescence (11, 13, and 15 years of age) and 27% during late adolescence (18 and 21 years of age). At 26 years of age, 12% of study members were obese. After adjusting for each individual's baseline body mass index (calculated as the weight in kilograms divided by the square of height in meters), depressed late adolescent girls were at a greater than 2-fold increased risk for obesity in adulthood compared with their nondepressed female peers (relative risk, 2.32; 95% confidence interval, 1.29-3.83). A dose-response relationship between the number of episodes of depression during adolescence and risk for adult obesity was also observed in female subjects. The association was not observed for late adolescent boys or for early adolescent boys or girls. CONCLUSIONS: Depression in late adolescence is associated with later obesity, but only among girls. Future studies should address reasons for these age and sex differences and the potential for intervention to reduce the risk for adult obesity in depressed older adolescent girls.     

Depressive symptomatology as a predictor of exposure to intimate partner violence among US female adolescents and young adults

OBJECTIVE: To examine whether depressive symptomatology is predictive of subsequent intimate partner violence victimization among a national prospective sample of female adolescents and young adults. DESIGN: Home interview data from 2 waves of the school-based National Longitudinal Study of Adolescent Health were used to examine whether baseline depressive symptomatology was associated with increased risk of past-year exposure to physical abuse by a current partner at 5-year follow-up, controlling for age, race/ethnicity, parental education, retrospective childhood physical and sexual abuse, and baseline dating violence and forced sex. SETTING: A stratified random sample of 80 US high schools and 52 middle schools. PARTICIPANTS: All young women (n = 1659) were in a current opposite-sex relationship at follow-up. MAIN EXPOSURE: Baseline past-week depressive symptomatology, measured as both a dichotomous and continuous variable. MAIN OUTCOME MEASURES: Past-year exposure to mild and moderate to severe physical abuse by a current intimate partner. RESULTS: In adjusted models with dichotomous depressive symptoms, high baseline symptom levels were associated with 1.86 times the odds of subsequent exposure to moderate to severe partner violence (95% confidence interval, 1.05-3.29). In adjusted models with continuous depressive symptoms, an increase of 1 SD in baseline symptom levels was associated with a 24% increase in odds of exposure to mild partner violence and a 24% increase in the odds of exposure to moderate to severe partner violence. CONCLUSIONS: The findings of this study suggest that depressive symptomatology among girls during adolescence is associated with increased risk of subsequent exposure to physical partner violence. Prevention, identification, and treatment of depressive symptomatology among adolescent girls may help to reduce the likelihood of subsequent victimization.     

The influence of school smoking policies on student tobacco use

OBJECTIVE: To investigate the association between smoking behavior among secondary school students and school smoking policies. DESIGN: Cross-sectional provincially representative study. SETTING: Quebec secondary schools. PARTICIPANTS: Complete data were available for 763 of 1058 students aged 13 years in 50 schools and for 768 of 1160 students aged 16 years in 57 schools. School principals provided data on school smoking policies. Main Exposure School smoking policies. Outcome Measure Student tobacco use. RESULTS: Of students aged 13 years, 3.8% of boys and 7.1% of girls smoked daily; 21.0% of boys and 25.2% of girls aged 16 years smoked daily. Of schools, 28.0% permitted staff to smoke indoors, 84.1% permitted staff to smoke outdoors on school grounds, and 83.2% permitted students to smoke outdoors on school grounds. Daily smoking was not associated with policies targeting student smoking or those targeting indoor smoking by staff. In multilevel analyses, girls aged 13 years were almost 5 times more likely to be daily smokers if they attended schools at which staff were permitted to smoke outdoors. CONCLUSIONS: Younger girls may be more susceptible to social influences at school related to tobacco use. School policies banning smoking by teachers and other school personnel within and outside the school should be an important component of comprehensive adolescent smoking prevention programs.     

Health-compromising behaviors: why do adolescents smoke or drink?: identifying underlying risk and protective factors

OBJECTIVES: To better understand the motivation for adolescent smoking and drinking and to identify the underlying risk and protective factors associated with these behaviors among adolescents. DESIGN: Cross-sectional, school-based survey of students in grades 5 through 12. PARTICIPANTS: A nationally representative sample of 2574 boys and 2939 girls in grades 7 through 12 from 297 public, private, and parochial schools across the United States who participated in The Commonwealth Fund Survey of the Health of Adolescent Girls and Boys in 1997. MAIN OUTCOME MEASURES: Sex-specific adjusted relative risks (RRs) and 95% confidence intervals (CIs) comparing self-reported regular smokers and regular drinkers by risk and protective factors with adolescents reporting none of these behaviors. RESULTS: Adolescent boys and girls were equally likely to be regular smokers (11.2%). The prevalence rate of regular drinking was only slightly higher for boys (22.4%) than it was for girls (19.3%). The rates of both health-risk behaviors were significantly higher for those reporting risk factors, and the strengths of associations varied by sex. Sex differences also emerged in motivation for engaging in these behaviors. When we adjusted for demographic characteristics, exposure to childhood abuse (RR, 4.1; 95% CI, 2.4-7.0) and stressful life events (RR, 2.4; 95% CI, 1.1-5.4) were strongly associated with increased risk for boys' regular smoking. Similar associations were found for regular drinking. For girls, a history of abuse (RR, 1.8; 95% CI, 1.1-2.8), violence within the family (RR, 2.2; 95% CI, 1.6-3.2), depressive symptoms (RR, 1.6; 95% CI, 1.0-2.4), and stressful life events (RR, 3.1; 95% CI, 1.8-5.6) were significantly associated with increased risk for regular smoking. Similar associations were again found for regular drinking. Parental support was protective against both health-risk behaviors for both sexes. Participation in extracurricular activities was associated with lower risk for regular smoking for boys (RR, 0.4; 95% CI, 0.2-0.7) and for girls (RR, 0.3; 95% CI, 0.2-0.5); however, there was no significant association between drinking behavior and participation in activities. CONCLUSIONS: The increased risk for regular smoking and regular drinking among adolescents with a history of abuse, family violence, depressive symptoms, and stressful life events suggests that routine screening for abuse, violence, and other family experiences should be an essential component of adolescent health care visits. Effective prevention programs to reduce smoking and drinking among adolescents should recognize that health-risk behaviors may be associated with other negative life experiences and that the strength of these associations differs by sex.     

Predictors of abdominal pain in schoolchildren: a 4-year population-based prospective study.

BACKGROUND: Chronic abdominal pain (CAP) is common among schoolchildren, but risk factors for its onset are still largely unknown. AIMS: To determine the frequency of onset of CAP in schoolchildren and investigate risk factors for its development. METHODS: 1411 schoolchildren aged 11-14 years were recruited from schools in North West England. Information was collected on recent pain symptoms and potential risk factors for developing CAP. Participants were followed up 1 and 4 years later and new episodes of CAP were identified. RESULTS: 22% reported new-onset abdominal pain at 1-year follow-up which persisted at 4-year follow-up (CAP). CAP was almost three times higher in girls than boys (34% vs 13%; chi(2): 26.0; p<0.001). In girls, reporting headache at baseline was the only predictive factor for CAP onset: those reporting headaches experienced a doubling in the risk of symptom onset (relative risk: 2.1; 95% confidence interval: 0.95 to 4.7). In contrast, in boys, development of CAP was independently predicted by daytime tiredness (3.0; 1.2 to 7.6), lack of school enjoyment (2.0; 0.95 to 4.2), adverse psychosocial exposures (2.3; 1.2 to 4.5) and taller stature (1.9; 0.8 to 4.5). CONCLUSION: Our results suggest that over 20% of adolescent schoolchildren experience new-onset non-self-limiting abdominal pain over a 1-year period. Future abdominal pain is predicted by previous somatic symptom reporting in girls and both somatic symptom reporting and psychosocial factors in boys. These risk factors indicate a possible mechanism for understanding the development of CAP, and might have important implications for both primary and secondary preventive strategies.     

Cross-sectional study of female students reporting anabolic steroid use

OBJECTIVE: To determine the characteristics of female US high school students reporting anabolic steroid use. DESIGN: Cross-sectional assessment using the 2003 Centers for Disease Control and Prevention national school-based Youth Risk Behavior Survey database. SETTING: Nationally representative sample of US high schools. PARTICIPANTS: Female students in grades 9 through 12 (n = 7544). MAIN OUTCOME MEASURES: Participants' self-reported anabolic steroid use was compared with other health-related behaviors and with sports participation. RESULTS: Prior or ongoing anabolic steroid use was reported by 5.3% of female high school students. Those adolescent girls had a marked increase in other health-compromising behaviors, including past 30-day use of alcohol (odds ratio [OR], 8.83; 95% confidence interval [CI], 5.49-14.20]), cigarettes (OR, 5.14; 95% CI, 3.14-8.42), marijuana (OR, 7.91; 95% CI, 5.20-12.04), cocaine (OR, 10.78; 95% CI, 6.18-18.81), and diet pills (OR, 4.86; 95% CI, 2.98-7.93). They were more likely to carry a weapon (OR, 7.54; 95% CI, 4.83-11.76), have had sexual intercourse before age 13 years (OR, 2.90; 95% CI, 1.58-5.33), and have had feelings of sadness or hopelessness almost every day for at least 2 consecutive weeks (OR, 4.13; 95% CI, 2.57-7.22). They were less likely to play school-sponsored team sports (OR, 0.52; 95% CI 0.34-0.80). Steroid users participating in sports shared the same problem behaviors as steroid users not participating in team athletics. CONCLUSION: Self-reported anabolic steroid use is not confined to adolescent girls in competitive athletics and is an indicator of adolescent girls with a marked increase in a cluster of other health-harming behaviors.     

Can neighborhoods explain racial/ethnic differences in adolescent inactivity?

OBJECTIVE: To determine if neighborhoods and their attributes contribute to racial/ethnic disparities in adolescent inactivity. METHODS: We undertook a cross-sectional analysis of the National Longitudinal Study of Adolescent Health (n = 17,007), a nationally representative school-based study in the United States. Stratifying by gender, we used multivariate linear regression and multi-level modeling to determine whether neighborhood of residence may partially explain racial/ethnic disparities in adolescent physical inactivity, defined as hours viewing television or videos/DVDs and/or playing computer/video games each week. RESULTS: Participants lived in largely segregated communities. Black and Hispanic adolescent girls reported higher levels of inactivity than White adolescent girls (21 vs. 15 vs. 13 hours/week, respectively, p <0.001). Similar patterns were seen in adolescent boys, with Black adolescent males reporting a mean of 26 hours/week; Hispanic boys a mean of 20 hours/week; and White boys a mean of 17 hours/week of inactivity (p <0.001). After accounting for between-neighborhood variation, there were no residual within-neighborhood differences in inactivity between Hispanic and White adolescent girls (gamma = -0.06, p =0.93); when living in the same neighborhood Hispanic and White girls had similar levels of inactivity. Black adolescent girls and boys were found to have higher levels of inactivity no matter where they lived (gamma =7.00, p <0.001 for girls; gamma = 6.96, p <0.001 for boys). Hispanic boys had similar patterns of inactivity to White boys (gamma =-1.57, p = 0.12). In both males and females, the reported rate of violent crime in the neighborhood was associated with inactivity, despite the individual's perception of his/her neighborhood as safe not being predictive. CONCLUSIONS: Although inactivity varies by race/ethnicity and gender, only in Hispanic adolescent girls does neighborhood fully explain the differential use. Our findings suggest that approaches other than changing neighborhood characteristics are needed to eliminate racial/ethnic disparities in adolescent inactivity.     

Effect of abuse on health: results of a national survey

HYPOTHESIS: The magnitude of risk would be highest for those reporting both types of abuse compared with those reporting 1 type or none. OBJECTIVE: To examine the independent associations between physical or sexual abuse or both and self-reported health status, mental health, and health-risk behaviors among a national school-based sample of adolescent girls. DESIGN: A secondary data analysis of a cross-sectional survey. SETTING: A nationally representative sample of 3015 girls in grades 5 through 12 from 265 public, private, and parochial schools (with an oversampling of urban schools) completed an anonymous survey conducted by the Commonwealth Fund Adolescent Health Survey. PATIENTS OR OTHER PARTICIPANTS: Girls were eligible for this study if they responded to 2 questions assessing past physical and sexual abuse. RESULTS: Among the respondents, 246 (8%) reported a history of physical abuse; 140 (5%), sexual abuse; and 160 (5%), both. Logistic regression controlling for grade, ethnicity, family structure, and socioeconomic status found that those who reported both types of abuse compared with those who did not report any were significantly more likely to experience moderate to severe depressive symptoms (adjusted odds ratio [AOR], 5.10), moderate to high levels of life stress (AOR, 3.28), regular smoking (AOR, 5.90), regular alcohol consumption (AOR, 3.76), use of other illicit drugs in the past 30 days (AOR, 3.44), and fair to poor health status (AOR, 1.74). Finally, girls who reported both types of abuse were 2.07 times more likely to report moderate to high depressive symptoms compared with those reporting only sexual abuse (95% confidence interval, 1.14-3.74). CONCLUSIONS: The magnitude of risk for adolescents reporting both types of abuse compared with no abuse is much greater than that for either abuse type alone. However, compared with both types, no significant increase in risk was detected in those reporting physical abuse only, and only depressive symptoms increased in those reporting sexual abuse only.     

Associations of weight-based teasing and emotional well-being among adolescents

BACKGROUND: Verbal harassment, such as bullying and hate speech, has received considerable attention recently, but less is known about weight-based teasing and its potential harmful effects on young people's psychosocial well-being. OBJECTIVE: To determine the associations of weight-based teasing and body satisfaction, self-esteem, depressive symptoms, and suicidal ideation and suicide attempts using a large sample of adolescents. DESIGN: Secondary analysis of survey and anthropometric data. SETTING: Ethnically and socioeconomically diverse communities in the urban and suburban school districts of the Minneapolis/St Paul metropolitan area. PARTICIPANTS: A school-based sample of 4746 adolescents in grades 7 to 12 at 31 public middle schools and high schools. MAIN OUTCOME MEASURES: Weight-based teasing from peers or family members, body satisfaction, self-esteem, depressive symptoms, and suicidal ideation and suicide attempts. RESULTS: Of the eligible students, 81.5% participated; 30.0% of adolescent girls and 24.7% of adolescent boys were teased by peers, and 28.7% of adolescent girls and 16.1% of adolescent boys were teased by family members. Approximately 14.6% of adolescent girls and 9.6% of adolescent boys reported teasing from both of these sources. Teasing about body weight was consistently associated with low body satisfaction, low self-esteem, high depressive symptoms, and thinking about and attempting suicide, even after controlling for actual body weight. These associations held for adolescent boys and girls, across racial, ethnic, and weight groups. Furthermore, teasing from 2 sources was associated with a higher prevalence of emotional health problems than either teasing from a single source or no teasing. CONCLUSIONS: Physicians and other health care providers should recognize the importance of weight-based teasing for young patients. Policy, programs, and education should focus on increasing awareness of what constitutes weight-based teasing, its potentially harmful effects on adolescents' emotional well-being, and reduction of this behavior.     

上海市中小学生自杀行为及心理社会相关因素的研究

目的 了解上海市中小学生自杀行为的现状，探索自杀行为的相关危险因素。方法 采用分级整群随机抽样方法，选取上海市9所学校：小学5年级、预备初中（预初）、初一、初二、高一和高二年级学生进行匿名自评问卷调查。问卷包括一般情况问卷、流行病学调查中心用抑郁量表、焦虑自评量表、青少年生活事件量表和贝克绝望量表，根据美国疾病控制预防中心（CDC）青少年危险行为调查所采用的方式设置最近12个月的自杀意念、自杀计划和自杀未遂行为调查。自杀行为的年级和性别差异用卡方检验，自杀意念的相关因素分析采用单因素和多因素Logistic回归模型。结果 ①发放问卷2 513份，当场收回有效问卷2 416份，其中男1 190份，女1 226份；调查人群年龄10~17岁；②调查人群中有自杀意念者368名（15.23%，368/2 416），有自杀计划者141名（5.84%，141/2 416），自杀未遂者42名（1.74%，42/2 416）；③自杀行为的性别差异：男生有自杀意念者178名（14.96%,178/1 190），有自杀计划者80名(6.72%，80/1 190)，自杀未遂者24名(2.02%，24/1 190)；女生有自杀意念者190名（15.50%，190/1 226），自杀计划者61名(4.98%，61/1 226)，自杀未遂者18名(1.47%，18/1 226)。男、女生自杀行为差异无统计学意义（P>0.05）；④自杀意念的发生随年级上升而升高（P<0.05）。调查显示高二年级学生自杀未遂的发生率最高（5.17%，6/116）,其次为预初年级（2.52%，13/516）, 小学5年级最低（0.86%，3/347）（P<0.05）。自杀计划的发生率各年级间差异无统计学意义（P>0.05）；⑤小学生自杀意念与所在学校、家庭住房条件显著相关；初中生的自杀意念与同伴关系、父亲文化水平和母子沟通显著相关；高中生的自杀意念与学习成绩、自由支配空余时间和父子沟通显著相关。所有年级学生的自杀意念均与青少年生活事件量表、抑郁量表、焦虑自评量表和贝克绝望量表分呈显著相关。结论 ①上海市中小学生自杀行为状况不容乐观，必须引起高度重视；②不同学习阶段学生的自杀行为影响因素有所不同，干预措施应有所侧重；③应及时发现和积极治疗情绪障碍，努力培养青少年应对不良生活事件的能力，以降低自杀行为发生。     

Randomized controlled trial of a primary care and home-based intervention for physical activity and nutrition behaviors: PACE+ for adolescents

OBJECTIVE: Many adolescents do not meet national guidelines for participation in regular moderate or vigorous physical activity (PA); limitations on sedentary behaviors; or dietary intake of fruits and vegetables, fiber, or total dietary fat. This study evaluated a health care-based intervention to improve these behaviors. DESIGN: Randomized controlled trial. SETTING: Primary care with follow-up at home. PARTICIPANTS: Eight hundred seventy-eight adolescent girls and boys aged 11 to 15 years. INTERVENTIONS: Two experimental conditions: (1) Primary care, office-based, computer-assisted diet and PA assessment and stage-based goal setting followed by brief health care provider counseling and 12 months of monthly mail and telephone counseling and (2) a comparison condition addressing sun exposure protection. MAIN OUTCOME MEASURES: Minutes per week of moderate plus vigorous PA measured by self-report and accelerometer; self-report of days per week of PA and sedentary behaviors; and percentage of energy from fat and servings per day of fruits and vegetables measured by three 24-hour diet recalls. Body mass index (calculated as weight in kilograms divided by the square of height in meters) was a secondary outcome. RESULTS: Compared with adolescents in the sun protection condition, girls and boys in the diet and PA intervention significantly reduced sedentary behaviors (intervention vs control change, 4.3 to 3.4 h/d vs 4.2 to 4.4 h/d for girls, respectively [P = .001]; 4.2 to 3.2 h/d vs 4.2 to 4.3 h/d for boys, respectively [P = .001]). Boys reported more active days per week (intervention vs control change: 4.1 to 4.4 d/wk vs 3.8 to 3.8 d/w, respectively [P = .01]), and the number of servings of fruits and vegetables for girls approached significance (intervention vs control change, 3.5 to 4.2 servings/d vs 3.5 to 3.9 servings/d, respectively [P = .07]). No intervention effects were seen with percentage of calories from fat or minutes of PA per week. Percentage of adolescents meeting recommended health guidelines was significantly improved for girls for consumption of saturated fat (intervention vs control change, 23.4% to 41.0% vs 18.5% to 31%, respectively [relative risk, 1.33; 95% confidence interval, 1.01-1.68]) and for boys' participation in d/wk of PA (intervention vs control change, 45.3% to 55.4% vs 41.9% to 38.0%, respectively [relative risk, 1.47; 95% confidence interval, 1.19-1.75]). No between-group differences were seen in body mass index. CONCLUSIONS: Improvements in some diet, PA, and sedentary behaviors in adolescents can be enabled through the use of a 1-year, integrated intervention using the computer, health provider counseling, mail, and telephone. The amount of intervention received may contribute to its efficacy.     

Behavior and injury in urban and rural adolescents.

OBJECTIVES: This study investigates the consistency of factors associated with adolescent injury in separate urban and rural samples. SAMPLES: Adolescents, 11-17 years old, in public schools in urban and rural Maryland (n = 2,712). METHODS: Separate bivariate and logistic regression analyses were conducted for each sample to determine individual and environmental factors associated with major and minor injuries experienced in the previous year. RESULTS: Multivariate analyses revealed that, for both samples, the probability of a major injury was highest for boys and, among both boys and girls, for those who played several team sports. Among rural youth, other significant covariates of both major and minor injuries were a tendency to engage in risky behavior and to use alcohol. For urban youth, being white, carrying a weapon for protection, attending an unsafe school, and working for pay were also significant covariates. Interactions were important and complex. CONCLUSIONS: The consistency of predictive factors, such as multiple sports team participation and risky and aggressive behaviors in completely different physical environments, underscores the need to address the contexts of heightened injury risk that some adolescents create wherever they live by playing sports and/or behaving in an antisocial, aggressive manner. Moreover, the perception of lack of safety in schools and neighborhoods is associated with increased injury rates, suggesting the need for policy interventions to target social environments as well as behavior.     

The relation between physical activity and mental health among Hispanic and non-Hispanic white adolescents

OBJECTIVE: To assess the relation of physical activity (PA) with feelings of sadness and suicidal thoughts and behaviors among Hispanic and non-Hispanic white adolescent boys and girls. DESIGN: Cross-sectional study using a modified 2001 Youth Risk Behavior Survey. PARTICIPANTS: One thousand eight hundred seventy Hispanic and non-Hispanic white adolescents, aged 14 to 18 years, attending high school in Nueces County, Texas. MAIN OUTCOME MEASURE: Logistic regression analysis was used to assess the relation between PA, including moderate and vigorous PAs, strength and toning, total PA, physical education class, and participation in team sports, and the dependent variables feelings of sadness and considering, planning, and attempting suicide. RESULTS: More boys reported participating in PA than girls (P<.001), and more girls than boys reported feelings of sadness and considering and planning suicide (P<.001). Greater attendance in physical education class was inversely related to feelings of sadness (odds ratio [OR], 0.80 [95% confidence interval (CI), 0.68-0.94]); participation in more total PA sessions per week was associated with a lower risk of considering suicide (OR, 0.72 [95% CI, 0.65-0.79]); and higher levels of vigorous PA (OR, 0.73 [95% CI, 0.57-0.93]), total PA (OR, 0.65 [95% CI, 0.48-0.87]), and strength and toning activity (OR, 0.64 [95% CI, 0.42-0.99]) were associated with a lower risk of planning suicide. CONCLUSIONS: These findings are consistent with a beneficial effect of PA on feelings of sadness and suicidal behaviors in Hispanic and non-Hispanic white boys and girls. Physical activity may be considered as part of an intervention strategy to improve adolescent health as a whole.