Abstract Objective: To investigate the association between oral contraceptive use and cardiovascular risks, including metabolic syndrome and their components in Brazilian adolescents. Method: This study used data from the Study of Cardiovascular Risks in Adolescents (Estudo de Riscos Cardiovasculares em Adolescentes - ERICA), a nationwide, cross-sectional, school-based study with individuals aged 12-17 years. Sociodemographic variables and OC use were assessed by a self-administered questionnaire. International Diabetes Federation criteria were used to define metabolic syndrome. Descriptive statistics were reported as prevalence and their respective confidence interval of 95% of oral contraceptives according to variables. Logistic regression was performed. Crude and adjusted odds ratios were calculated. Results: This subsample was composed of 22,682 female adolescents, of which 12.65% reported using oral contraceptives and their use was associated with hypertension and hypertriglyceridemia. These associations remained statistically significant after adjusting for age, school region, race, and tobacco use with an increase of 2.68 (1.66 - 4.32) and 3.45 (2.56 - 4.65) times, respectively. Conclusion: The present study was the first to examine the association between the use of oral contraceptives and cardiovascular risk factors among the largest number of female Brazilian adolescents. This method was significantly associated with hypertension, hypertriglyceridemia. Teenagers using oral contraceptives should be monitored for side effects, including blood pressure measurements and advised to avoid smoking.

Abstract Objective To investigate the association between asthma and sleep duration in participants of the Study of Cardiovascular Risks in Adolescents. Materials and methods Cross-sectional, national, school-based study, involving adolescents aged 12-17 years. In the period between 2013−14, data from 59,442 participants were analyzed. Bivariate analysis between current asthma and short sleep duration, defined as < 7 h/night, was performed separately with the other variables analyzed: sex, age group, type of school, weight categories, and common mental disorders. Then, different generalized linear models with Poisson family and logarithmic link functions were used to assess the independence of potential confounding covariates associated with both asthma and short sleep duration in the previous analysis. Crude and adjusted prevalence ratios and respective 95% confidence intervals were calculated, and a value of p < 0.05 was considered significant for all analyses performed. Results Prevalence of current asthma was 13.4%, being significantly higher among students with short sleep duration (PR: 1.17; 95% CI: 1.01-1.35; p = 0.034). This remained significant even after adjusting for the other study covariates. Conclusion There was a positive association between the prevalence of current asthma and short sleep duration among Brazilian adolescents. Considering the high prevalence and morbidity of the disease in this age group, the promotion of sleep hygiene should be considered as a possible health strategy aimed at contributing to better control of asthma in this population.

RESUMO Objetivo: Avaliar a associação entre a prevalência de asma e níveis séricos de vitamina D em adolescentes brasileiros. Métodos: Estudo transversal de base escolar com adolescentes de 12 a 17 anos provenientes de quatro grandes cidades brasileiras em diferentes latitudes (Fortaleza, Rio de Janeiro, Brasília e Porto Alegre). Informações sobre o diagnóstico de asma, estilo de vida e características sociodemográficas foram coletadas por meio de questionários autoaplicáveis. As concentrações séricas de calcifediol foram dicotomizadas: suficientes (≥ 20 ng/mL) e insuficientes/deficientes (< 20 ng/mL). Foram realizadas análises bivariadas entre os níveis de vitamina D e a prevalência de asma ativa (AA), além de outras variáveis, por meio do teste do qui-quadrado. Modelos lineares generalizados foram configurados para analisar possíveis fatores de confusão (p < 0,20). Resultados: Entre 2013 e 2014, foram avaliados 1.053 adolescentes. A prevalência de AA e níveis insuficientes/deficientes de calcifediol foram de 15,4% e 21%, respectivamente. Não houve associações estatisticamente significativas entre AA e hipovitaminose D. As prevalências de AA e insuficiência de vitamina D foram, respectivamente, 2,34 (IC95%: 1,28-4,30) e 3,22 (IC95%: 1,75-5,95) vezes maiores em Porto Alegre que no Rio de Janeiro, independentemente de possíveis fatores de confusão. No entanto, não foram observadas associações significativas entre a prevalência de AA e variáveis relacionadas à vitamina D em nenhuma das cidades. Conclusões: Não se observou nenhuma associação entre AA e níveis baixos de vitamina D em adolescentes residentes em diferentes latitudes no Brasil.

ABSTRACT Objective: To evaluate the association between asthma prevalence and serum levels of vitamin D in Brazilian adolescents. Methods: This was a cross-sectional, school-based study involving adolescents between 12-17 years of age from four large Brazilian cities located at different latitudes (Fortaleza, Rio de Janeiro, Brasília, and Porto Alegre). Information on asthma diagnosis, lifestyle, and sociodemographic characteristics was collected by means of self-administered questionnaires. Serum concentrations of calcifediol were dichotomized as sufficient (≥ 20 ng/mL) or insufficient/deficient (< 20 ng/mL) levels. Bivariate analyses were carried out between vitamin D levels and prevalence of active asthma (AA), as well as other variables in study, using the chi-square test. Generalized linear models were configured to analyze potential confounding factors (p < 0.20). Results: Between 2013 and 2014, 1,053 adolescents were evaluated. The prevalences of AA and insufficient/deficient levels of calcifediol were 15.4% and 21%, respectively. There were no statistically significant associations between AA and hypovitaminosis D. The prevalences of AA and vitamin D insufficiency were, respectively, 2.34 (95% CI, 1,28-4.30) and 3.22 (95% CI, 1.75-5.95) times higher in Porto Alegre than in Rio de Janeiro, regardless of possible confounding factors. However, no significant associations were found between the prevalence of AA and vitamin-D-related variables in any of the cities. Conclusions: No association was found between AA and low levels of vitamin D in adolescents living at different latitudes in Brazil.

Resumo: Objetivo: Investigar a associação entre asma, tabagismo e possíveis fatores associados em adolescentes brasileiros. Métodos: Estudo transversal, nacional, de base escolar, envolveu adolescentes com 12 a 17 anos, participantes do Estudo de Riscos Cardiovasculares em Adolescentes (ERICA). Os 66.394 participantes responderam questionários autopreenchíveis com questões sobre asma, tabagismo, estilo de vida e dados sociodemográficos. Foram realizadas análises bivariadas entre asma ativa e asma grave e demais variáveis do estudo, com o uso de χ2. Em seguida, foram estimadas as razões de prevalência (RP) brutas e ajustadas e seus respectivos intervalos de confiança de 95% (IC 95%), entre asma ativa/asma grave e variáveis de tabagismo, corrigidas pelas variáveis sociodemográficas e de estilo de vida, através de modelos lineares generalizados com regressão de Poisson, função de ligação logarítmica e variância robusta. Resultados: A prevalência de asma ativa e asma grave foi significativamente mais elevada naqueles expostos a experimentação (asma ativa: RP = 1,78; IC 95%: 1,51-2,09; asma grave: RP = 2,01; IC 95%: 1,35-2,98); tabagismo atual (asma ativa: RP = 2,08; IC 95%: 1,65-2,64; asma grave: RP = 2,29; IC 95%: 1,38-3,82); tabagismo frequente (asma ativa: RP = 2,25; IC 95%: 1,64-3,07; AG = 2,41; IC 95%: 1,23-4,73) e tabagismo passivo (asma ativa: RP = 1,47; IC 95%: 1,27-1,67; asma grave: RP = 1,66; IC 95%: 1,19-2,32). As associações permaneceram significativas após ajuste. Conclusão: A asma e o tabagismo se associaram de modo significativo em adolescentes brasileiros independente de fatores sociodemográficos e estilo de vida, especialmente naqueles com doença mais grave.

Abstract Objective: To investigate the association between smoking and asthma, and possible associated factors in Brazilian adolescents. Methods: A cross-sectional, national, school-based study with adolescents aged 12-17 years, participants in the Study of Cardiovascular Risks in Adolescents (Estudo de Riscos Cardiovasculares em Adolescentes - ERICA). A total of 66,394 participants answered a self-administered questionnaire with questions about asthma, smoking, lifestyle and sociodemographic variables. Bivariate analysis between Current Asthma (CA) and Severe Asthma (SA) and the other study variables were performed using Chi-squared. Then, the crude and adjusted Prevalence Ratios (PR), and respective 95% Confidence Intervals (95% CI) of current asthma/severe asthma and smoking variables, corrected for sociodemographic and lifestyle variables, were estimated using generalized linear models with Poisson regression, logit link, and robust variance. Results: The prevalence of current asthma and severe asthma were significantly higher in adolescents who were exposed to: experimentation (current asthma: PR = 1.78, 95% CI: 1.51-2.09; severe asthma: PR = 2.01; 95% CI: 1.35-2.98); current smoking (current asthma: PR = 2.08, 95% CI: 1.65-2.64; severe asthma: PR = 2.29; 95% CI: 1.38-3.82); regular smoking (current asthma: PR = 2.25, 95% CI: 1.64-3.07; severe asthma: PR: 2.41; 95% CI: 1.23-4.73); and passive smoking (current asthma: PR = 1.47, 95% CI: 1.27-1.67; severe asthma: PR = 1.66; 95% CI: 1.19-2.32); these associations remained significant after adjustment. Conclusions: Asthma and smoking were significantly associated in Brazilian adolescents, regardless of the sociodemographic and lifestyle factors, notably in those with more severe disease.