The Causal Association Between Smoking and Depression Among South Korean Adolescents

This study used a longitudinal design to explore the causal inference between smoking and depression, which are prevalent health problems in adolescence. To answer the research question, existing data from the Korea Youth Panel Survey were analyzed. Data contain four Waves, and two samples were selected in Wave 3: teens who did not smoke (Sample 1) and teens who were not depressed (Sample 2). The effect of depression in Wave 3 on smoking in Wave 4 was examined with Sample 1; the effect of smoking in Wave 3 on depression in Wave 4 was examined with Sample 2. In the analyses, factors that may influence the association between the two conditions were controlled. Those factors were characteristics relative to demographics, family, school, friends, and individuals. The results indicated that after adjusting for the other factors, depression was a successful predictor of smoking but not the other way around. The findings have two crucial implications for nursing practice. Nursing professionals need to provide alternatives for depressed teens to change their negative moods in a timely manner, which could help prevent smoking initiation. Also, nursing professionals should take into account depression-related problems when they develop strategies for smoking cessation, considering the crucial link between depression and smoking.