Trends in Depressive Symptoms and Suicidality of South Korean Adolescents: Comparison of Expected and Observed Prevalence During the COVID-19 Pandemic

PURPOSE: Depressive symptoms and suicidality of adolescents during the COVID-19 pandemic are emerging public health issues. However, there is a lack of representative studies on adolescents' mental health that considers the preceding secular trends. METHODS: This descriptive study used nationally representative cross-sectional data of Korean adolescents from the Korea Youth Risk Behavior Survey from 2005 to 2020 (N = 1,035,382). We utilized joinpoint regression analysis to explore the temporal prevalence trends of depressive symptoms, suicidal ideation, and suicide attempts. Based on the annual percentage change until 2019, the expected and actual prevalence in 2020 (N = 54,948) was compared to describe departures of prevalence from the trend line. These trends between sex, school level, ethnic status, and socioeconomic status were also compared. RESULTS: Considering the recent increase in secular trends until 2019, the actual observed values in 2020 were lower than expected by 13% in depressive symptoms, 20% in suicidal ideation, and 40% in suicide attempts. The gap between sexes, school levels, ethnic status, and socioeconomic groups was similar or narrowed in 2020 compared to previous trends. DISCUSSION: We observed a lower prevalence of depressive symptoms and suicidality among Korean adolescents than expected about 9 months from the beginning of the COVID-19 pandemic despite the recent increase in secular trends.