Prevalência e fatores associados a indicadores negativos de saúde mental em adolescentes estudantes do ensino médio em Pernambuco, Brasil

objectives: to identify the prevalence of and factors associated with negative mental health indicators among adolescents. methods: a previously validated questionnaire was used to gather data on 4,207 adolescents (aged between 14 and 19 years) attending high school, selected by way of conglomerate sampling in two stages. results: the prevalence of sadness, feelings of loneliness, thoughts of suicide, difficulty sleeping because of anxiety, and plans to commit suicide was 29.7%, 15.8%, 11.2%, 10.0% and 7.8% respectively. the prevalence for all indicators was higher among girls, with sadness being the most prevalent indicator. it was identified that skin-color was not a factor associated with the occurrence of negative mental health indicators, while not living with parents showed a significant degree of association with feeling of loneliness and thoughts of suicide. conclusions: the prevalence of feelings of loneliness and sadness is high and girls are a subgroup that is more vulnerable to all the negative mental health indicators.