The Association between Secondhand Smoke and Stress, Depression, and Suicidal Ideation in Adolescents

Background: Secondhand smoke (SHS) is an important risk factor for adolescents' health. Several studies have reported that SHS is as dangerous as active smoking. Therefore, this study aimed to investigate the association between exposure to SHS and mental health, including stress, depression, and suicidal ideation, in adolescents. Methods: Using raw data from the 2018 14th Korea Youth Risk Behavior Web-Based Survey, we analyzed the effects of sociodemographic characteristics on stress, depression, suicidal ideation in 51,500 students, including 85.8% of all sampled students (n = 60,040), after excluding students with a history of smoking, and then we performed logistic regression analysis to determine the level of exposure to SHS and its impact on stress, depression, and suicidal ideation. Results: The increased level of exposure to SHS was positively associated with stress, depression, and suicidal ideation. Furthermore, stress, depression, and suicidal ideation increased as the level of SHS increased, after adjusting for variables such as age, gender, education level of the father and mother, school achievement, economic status, inhabitation, and drinking. Conclusions: This study demonstrates that SHS is positively associated with risk of mental health problems, including stress, depression, and suicidal ideation, in adolescents. Further research and policy strategies and systems to prevent and manage exposure to SHS in adolescents are required.