Factors associated with extreme weight loss behaviors among adolescents of Northeastern Brazil: a hierarchical approach/Comportamentos extremos para perda de peso e fatores associados em adolescentes do Nordeste brasileiro: urna abordagem hierarquica

The objective of this article is to identify the prevalence and evaluate the factors associated with extreme weight loss behaviors among adolescents of Northeastern Brazil. Cross-sectional study with 2,439 adolescents from Sample 2 (2015) of the National School-based Health Survey. Extreme weight loss behaviors, such as self-induced vomiting, laxative use and use of medicines or formulas (outcome) and independent variables were evaluated using a self-administered electronic questionnaire. The statistical analysis was performed following a hierarchical conceptual model. The prevalence of extreme weight loss behaviors in the sample was 12.1%. Among the factors that showed significant association with the outcome, we emphasize the administration model of the private school (PR = 0.62; CI = 0.46-0.84), bullying related to body appearance and for other reasons (PR = 1.62; CI = 1.19-2.20), forced sexual intercourse (PR =2.65; CI = 1.90-3.69), insomnia (PR = 1.84; CI = 1.43-2.37), and be perceived as fat or very fat (PR = 1.90; CI = 1.50-2.42). Moderate prevalence of extreme weight loss behaviors was identified among adolescents. Socioeconomic factors, exposure to violence, mental health, and body image were associated with the adoption of these behaviors. Key words Purgative behavior, Weight loss, Induced vomiting Laxatives, Adolescent O objetivo deste artigo e identificar a prevalencia e avaliar os fatores associados aos comportamentos extremos para perda de peso em adolescentes do Nordeste brasileiro. Estudo transversal com 2.439 adolescentes da Amostra 2 (2015) da Pesquisa Nacional de Saude do Escolar. Os comportamentos extremos para perda de peso (desfecho) e as variaveis independentes foram avalladas por meio de um questionario eletronico autoaplicavel. A analise estatistica foi realizada seguindo um modelo conceitual hierarquico. A prevalencia de comportamentos extremos para perda de peso na amostra foi de 12,1%. Entre os fatores que mostraram associacao significativa com o desfecho, destacam-se a situacao administrativa da escola privada (RP = 0,62; IC = 0, 46-0,84), ser vitima bullying relacionado a aparencia corporal e pelos demais motivos (RP = 1,62; IC = 1,19-2,20), serforcado a ter relacao sexual (RP = 2,65; IC = 1,90-3,69), ter insania (RP = 1,84; IC = 1,43-2,37) e se autoperceber como gordo ou muito gordo (RP = 1,90; IC = 1,50-2,42). Prevalencia moderada de comportamentos extremos para perda de peso foi identificada entre os adolescentes. Os fatore