Helena Fonseca

Health risk behaviors and associated risk and protective factors among Brazilian Adolescents in Santos, Brazil

OBJECTIVE To describe the prevalence of health risk behaviors and identify risk and protective factors that are associated with several health risk behaviors (cigarette smoking, drug use, onset of sexual intercourse before age 15, pregnancy, gun-carrying, suicidal ideation, and suicide attempts) among adolescents in Brazil, as well as to explore gender differences. METHODS We estimated prevalence rates, evaluated bivariate associations, and explored multivariate analyses using logistic regression on data from a 1997 survey of adolescent health among 2059 eighth- and 10(th)-grade students in Santos, Brazil. RESULTS Youth in Santos, Brazil report high rates of gun-carrying, suicidal thoughts and attempts, sexual intercourse, and pregnancy. Factors associated with diminished involvement for nearly all health risk behaviors, for both boys and girls, included having good family relationships, and feeling liked by friends and teachers. Factors associated with increases in nearly all health risk behaviors were: gun-carrying and gun availability in the home, drug use, and sexual abuse. CONCLUSIONS Factors that are associated with a wide range of health risk behaviors among adolescents in Brazil appear to parallel those found in industrialized countries: access to guns, substance use, and sexual abuse. Likewise, connectedness to family, school, and peers is consistently the protective factor associated with diminished risky behaviors.

Validity of BMI based on self-reported weight and height in adolescents

Aim:  To assess in a subset of a nationally representative sample of Portuguese adolescents, the validity of Body Mass Index (BMI) based on self‐reported weight and height.

Are overweight and obese adolescents different from their peers

OBJECTIVE To identify psychosocial and lifestyle indicators including alcohol consumption, that may distinguish overweight and obese adolescents from their peers, and align them with other adolescents with chronic conditions. METHODS The sample included 6 131 6th, 8th, and 10th grade public school Portuguese students, aged 11-16 years, who participated in the Health Behavior in School-Aged Children (HBSC)/WHO survey of adolescent health. Body mass index (BMI) was based on self reported weight and height. Separate analyses of psychosocial and behavioral variables were conducted by gender, age group, and BMI, using Chi square, and ANOVA. RESULTS Obese and overweight teens when compared with non-overweight teens, were more likely to report a negative attitude towards their appearance; to believe that others made negative comments about them; had a lower level of life satisfaction; had more difficulty in making new friends, and were more likely to describe themselves as unhappy. Moreover, obese teens were significantly more likely than their non-obese peers to describe themselves as having health problems, to report drinking alcohol daily, as well as having been drunk more than 10 times. CONCLUSIONS The present study provides further evidence regarding the association between overweight and obesity in adolescence, and body image dissatisfaction, poorer self-assessed health status, potential social isolation, decreased life satisfaction, and problematic alcohol consumption patterns. Overweight and obese adolescents should, where possible, be reached with appropriate interventions addressing the broad spectrum of their psychological needs, enhancing their skill development for behavioral change, and providing support for dealing with potentially harmful behaviors.

Are overweight adolescents at higher risk of engaging in unhealthy weight-control behaviours?

Aim: To examine correlates of unhealthy weight‐control behaviours (UNWCB), and to explore possible associated variables.

Physical activity and cardiorespiratory fitness, but not sedentary behavior, are associated with carotid intima-media thickness in obese adolescents

AbstractThis study aimed to analyze the associations between sedentary behavior, physical activity (PA), and cardiorespiratory fitness (CRF), with carotid intima-media thickness (cIMT), a marker of atherosclerosis already present at an early stage among obese adolescents. The associations between anthropometric measures, sedentary time, PA, CRF, and cIMT of 54 Caucasian obese adolescents were analyzed using partial correlations (controlling for age and sex) and multiple linear regressions. Differences between participants with and without a healthy CRF were also analyzed using independent sample t test. Sedentary time did not correlate with any of the variables. Light physical activity correlated positively with mean cIMT (r(38) = 0.36, p = 0.024). Moderate physical activity (MPA) correlated positively with both mean (r(38) = 0.37, p = 0.018) and maximum (r(38) = 0.33, p = 0.039) cIMT. CRF was inversely associated with mean cIMT (r(40) = −0.36, p = 0.019), even when controlling for sedentary time (r(37) = −0.35, p = 0.030). The best predictors of cIMT were MPA and weight. No significant differences in cIMT were found between participants with healthy and unhealthy CRF. Conclusion: Although we need to be cautious due to the limitations of the study, the results suggest that despite the importance of decreasing sedentary time, increasing PA intensity may be more effective in improving endothelial structural health among obese adolescents.What is Known:• Pediatric obesity is associated with increased carotid intima-media thickness (cIMT).• Physical activity may have a relevant role in cIMT development.What is New:• Cardiorespiratory fitness (CRF) may be a key moderator of this process.• Inherited CRF may be protective against cIMT development in obese adolescents.

Emotional, behavioural and social correlates of missing values for BMI

Objective: To examine the emotional, behavioural and social correlates of missing values for body mass index (BMI) in a nationally representative sample of Portuguese youth. Design and methods: 6131 Portuguese public school students aged 11–16 years in 6th, 8th and 10th grades who participated in the 2002 HBSC/WHO survey of adolescent health were included. Those not reporting their weight and/or height were compared with their peers. Bivariate analyses of psychosocial and behavioural variables were conducted to compare the two groups. Multivariate logistic regression was used to determine if variables significantly associated with missing values for BMI at a bivariate level predicted missing BMI when controlling for all other variables in the model. Results: Of 6131 adolescents answering the questionnaire, 661 (10.8%) did not report their weight and/or height. Gender was not associated with missing BMI. Missing values were significantly predicted by younger age (adjusted odds ratio (aOR) = 2.56, 95% CI 1.99 to 3.29, p<0.001), sedentary lifestyle (aOR = 1.53, 95% CI 1.16 to 2.01, p<0.01), poor body satisfaction (aOR = 1.34, 95% CI 1.19 to 1.51, p<0.001), absence of father (aOR = 1.62, 95% CI 1.14 to 2.30, p<0.01), lack of friends of the opposite sex (aOR = 1.65, 95% CI 1.03 to 2.66, p<0.05) and poor perception of academic achievement (aOR = 1.23, 95% CI 1.06 to 1.42, p<0.01). Discussion: Our findings suggest that those with missing values for BMI tend to have poorer body image, poorer health behaviours and poorer social networks. These results have implications for potential bias in the results of studies that do not account for missing BMI.

Lifestyle and treatment adherence among overweight adolescents

This study evaluated the influence of overweight adolescents’ lifestyle on the adherence to weight control, and identifies their predictors. Participants were 94 adolescents, aged 12–18 years, attending a Paediatric Obesity Clinic. Lifestyle was assessed using the “Adolescent Lifestyle Profile” and treatment adherence through the “Therapeutic Adherence to Weight Control Questionnaire.” Adherence to weight control was associated with various lifestyle domains. Several predictors were identified for lifestyle and adherence to weight control among overweight adolescents. A broad array of inter-correlations and predictors were identified and should be taken into account when designing adolescent weight control interventions.

Health promoting behaviors in adolescence: validation of the Portuguese version of the Adolescent Lifestyle Profile

OBJECTIVE Reliable and valid instruments are essential for understanding health-promoting behaviors in adolescents. This study analyzed the psychometric properties of the Portuguese version of the Adolescent Lifestyle Profile (ALP). METHODS A linguistic and cultural translation of the ALP was conducted with 236 adolescents from two different settings: a community (n=141) and a clinical setting (n=95). Internal consistency reliability and confirmatory factor analysis were performed. RESULTS Results showed an adequate fit to data, yielding a 36-item, seven-factor structure (CMIN/DF=1.667, CFI=0.807, GFI=0.822, RMR=0.051, RMSEA=0.053, PNFI=0.575, PCFI=0.731). The ALP presented a high internal consistency (α=0.866), with the subscales presenting moderate reliability values (from 0.492 to 0.747). The highest values were in Interpersonal Relations (3.059±0.523) and Positive Life Perspective (2.985±0.588). Some gender differences were found. Findings showed that adolescents from the clinic reported an overall healthier lifestyle than those from the community setting (2.598±0.379 vs. 2.504±0.346; t=1.976, p=0.049). CONCLUSION The ALP Portuguese version is a psychometrically reliable, valid, and useful measurement instrument for assessing health-promoting lifestyles in adolescence. The ALP is cross-culturally validated and can decisively contribute to a better understanding of adolescent health promotion needs. Additional research is needed to evaluate the instruments predictive validity, as well as its clinical relevance for practice and research.

Are adolescent weight-related problems and general well-being essentially an issue of age, gender or rather a pubertal timing issue?

Abstract Objective: To compare the characteristics of a set of weight-related and well-being variables among adolescents according to gender and age. It was hypothesised that time of puberty, not age in itself, might be the turning point for gender dissimilarities. Methods: Data were drawn from the Portuguese 2006 HBSC/WHO database and were disaggregated by gender and age group. Groups were compared for dieting, body image, health perception and happiness variables on the bivariate level using cross-tabulations. Separate analysis of the dependent variables was further conducted for 11-year-olds comparing males with pre- and post-menarche females. Results: Dieting and a negative body image were consistently more prevalent among girls and increased with age. At 11 years significantly more post-menarche girls were dieting and dissatisfied with their body image than boys and their pre-menarche counterparts. A poor self-rated health and the perception of unhappiness tended to be more common among older adolescents and among girls. Conclusions: Pubertal timing, and not age in itself, appears as the turning point for gender dissimilarities. Both gender- and age-specific differences as well as pubertal timing have to be taken into account by any physician when assessing an adolescent in order to be able to adapt the intervention.

Short- and medium-term impact of a residential weight-loss camp for overweight adolescents.

Abstract Introduction: Management of adolescent obesity in clinical practice has been usually centered on the promotion of healthy eating and an active lifestyle, with a weak evidence base. In search of creative and more effective interventions, our objective was to evaluate the immediate and follow-up effectiveness of a residential camp program for obese adolescents. Methods: A total of 28 obese adolescents (15 girls), mean age 13.3±1.7 years and body mass index (BMI) 30.3±5.4 kg/m2, who were attending a tertiary health unit, enrolled in a 2-week camp. The activities were prepared and supervised by different specialists. All adolescents were assessed for anthropometric and psychosocial variables including body image, self-esteem, quality of life and depressive symptoms. Evaluations were conducted on the first and last day of the camp and at 6 months’ follow-up. The effect of treatment was analyzed using analysis of variance (ANOVA) mixed models. Results: At the end of the camp, weight was reduced by –2.7±1.2%, BMI by –0.8±0.4 units and waist circumference by –2.8±9.8 cm. A reduction in depressive symptoms was identified, with greater reductions in BMI associated with a more significant improvement in depressive symptoms. At the 6 months’ follow-up only girls maintained BMI reduction, with boys having increased their BMI. Discussion: In the short-term the camp was effective in reducing BMI and improving depressive symptoms. Only girls were able to proceed with BMI reduction at 6 months. These gender differences should be further explored. Ongoing research is examining the maintenance of these improvements.