Korea Youth Risk Behavior Web-based Survey Research Articles

Trends in socioeconomic inequality in e-cigarette use among adolescents in South Korea.

The global rise in e-cigarette use among adolescents is alarming, with associated socioeconomic inequalities posing potential public health risks. This study examined trends in the socioeconomic inequality in e-cigarette use among South Korean adolescents to inform future regulatory directions. Socioeconomic inequalities in e-cigarette use among Korean adolescents were assessed using data from the Korea Youth Risk Behavior Web-based Survey (KYRBS) from 2011 to 2023. The Concentration Index, a well-established method for measuring health inequalities, was employed. Additionally, this study investigated how the smoking behaviors of family members and friends influence socioeconomic inequality in e-cigarette use among Korean adolescents, using a decomposition analysis. The Concentration Index values showed a clear, fluctuating downward trend over 13 years, from -0.12 (95% CI: -0.13 - -0.10) in 2011 to -0.24 (95% CI: -0.26 - -0.21) in 2023. Decomposition analysis revealed that smoking among peer groups, including friends and siblings, was the primary contributor to socioeconomic inequality in e-cigarette use, followed by maternal smoking. Socioeconomic inequalities in adolescent e-cigarette use in South Korea are widening, particularly among low socioeconomic status groups. The impact of peer groups on socioeconomic inequalities in e-cigarette use among adolescents is concerning.

Comparative study on health behaviors among adolescents with chronic allergic disease before and during COVID-19 using data from the Korean Youth Health Panel Surveys

BackgroundThis study aimed to investigate the changes in the health behaviors and subjective health perception of adolescents with chronic allergic disease, including atopic dermatitis, asthma, and allergic rhinitis, amidst the coronavirus disease 2019 (COVID-19) pandemic in South Korea.MethodsThis study used the 15th (2019) and 17th (2021) raw data obtained from the Korea Youth Risk Behavior Web-based Survey (KYRBWS), conducted by the Ministry of Health and Welfare of South Korea. Data were analyzed using multiple logistic regression with complex sampling using weighted values. Odds ratios with 95% confidence intervals for six health behaviors and subjective health perception were used as the major variables.ResultsSix health behaviors (dietary habits, weight gain, smoking, alcohol consumption, sleep time, and physical activity) changed substantially during COVID-19. There was an increase in the duration of sedentary activities, a slight increase in BMI, and improvements in mental health. Concurrently, there was a decrease in alcohol consumption, sleep duration, and the consumption of sweetened beverages. Despite these improvements in big six health behaviors, adolescents with chronic illnesses continue to perceive themselves as unhealthy.ConclusionsThese findings suggest that the follow-up and monitoring of health behaviors and subjective health perception in adolescents with chronic allergic diseases during the COVID-19 pandemic are necessary. Understanding the mechanisms underlying sustained behavioral change can inform the development of interventions to promote healthy behavior after the pandemic has passed.

Health-Related Behaviors and Perceived Health Status According to Water and Sugar-Sweetened Beverage Intake in Korean Adolescents.

The objective of this study was to determine the relationship between water and sugar-sweetened beverage (SSB) intake, health behaviors, and self-perceived health status using data from the 2019 Korea Youth Risk Behavior Web-based Survey (KYRBS). The subjects included in this analysis were 57,302 Korean adolescents from the 7th to 12th grades. The intake patterns of water and SSBs were categorized into four groups: Group I, adequate water intake (≥4 cups/day) and low frequency of SSB intake (≤1-2 times/week); Group II, adequate water intake and high frequency of SSB intake; Group III, inadequate water intake (<4 cups/day) and low frequency of SSB intake; Group IV, inadequate water intake and high frequency of SSB intake (≥3 times/week). Complex sample analyses were used for considering strata, clusters, and weights for samples. Significant differences were observed in the distribution of sociodemographic characteristics between the water and SSB intake groups. As grade levels increased or if students were female, there was a significant increase in the proportion of students characterized by low water intake and high consumption of SSB. Adolescents with healthier beverage habits, characterized by adequate water intake and low frequency of SSB consumption (Group I), generally abstained from smoking and alcohol, were more physically active, and maintained a desirable diet, reporting a better perceived health status. In contrast, those with higher SSB consumption and inadequate water intake (Group IV) were more likely to perceive their health as poor, with higher rates of smoking and alcohol use, lower physical activity levels, and poorer dietary habits compared to Group I. In conclusion, adolescents with desirable beverage consumption habits differed by sex and grade and they reported positive health behaviors and better overall health status. This suggests that there is a need for more active education and intervention in schools and families, as well as increased efforts by adolescents to promote healthy beverage habits.

Association between watching eating broadcasts like mukbang and cookbang and generalized anxiety disorder among Korean adolescents

BackgroundAnxiety disorders are common during adolescence; therefore, detecting anxiety disorders among adolescents and providing appropriate treatment are crucial. Studies have suggested that watching online audiovisual broadcasts like mukbang and cookbang (hereafter mukbang), where hosts eat or cook food, may influence anxiety disorders. However, there is insufficient research on the association between watching mukbang and generalized anxiety disorder (GAD). Therefore, we investigated the association between watching mukbang and GAD among Korean adolescents.MethodsWe analyzed 51,764 adolescents who participated in the 2020 Korea Youth Risk Behavior Web-Based Survey (KYRBS). The participants were asked how frequently they watched mukbang per week over the past 12 months. Anxiety disorders were assessed using the generalized anxiety disorder-7 (GAD-7) questionnaire. A multiple logistic regression analysis was performed after adjusting for confounding variables.ResultsThe prevalence of GAD was higher among adolescents who watched mukbang compared to those who did not (aOR: 1.100, 95% CI: 1.026–1.180, P = 0.008 in male participants; aOR: 1.090, 95% CI: 1.003–1.185, P = 0.042 in female participants). The frequency of watching mukbang showed a dose-dependent relationship with a greater likelihood of GAD in female adolescents.ConclusionThis study’s results showed that watching mukbang is associated with GAD in Korean adolescents. Proper interventions for mental health are needed for adolescents who watch mukbang.

The Association between High-Caffeine Drink Consumption and Anxiety in Korean Adolescents.

As excessive caffeine intake may be associated with anxiety disorders, one of the most prevalent mental illnesses among adolescents globally, this study investigated the association between high caffeine consumption and anxiety in a nationally representative sample of South Korean adolescents. 46,873 participants from the Korea Youth Risk Behavior Web-based Survey (KYRBS) 2022 were included. The Generalized Anxiety Disorder-7 (GAD-7) questionnaire was used to evaluate anxiety symptoms. Survey questions determined the number of times each participant consumed high-caffeine drinks per week. The chi-square test was used to investigate and compare the general characteristics of the study population, and a modified Poisson regression was used to analyze the relationship. Both male and female participants reporting excessive high-caffeine drink consumption exhibited higher anxiety levels (adjusted prevalence ratio [aPR]: 1.19, 95% confidence interval [CI]: 1.08-1.31 in males; aPR: 1.14, CI: 1.05-1.23 in females). This association remained statistically significant in subgroup analyses, particularly among high school students and those with a shorter sleep duration. The relationship between high-caffeine drink consumption and anxiety strengthened with increasing anxiety levels. Additionally, there was a dose-dependent relationship between the prevalence of anxiety and high-caffeine drinks. High caffeine consumption increases anxiety in South Korean adolescents. This association proved consistent regardless of sex or other socioeconomic factors.

Differences in risk of generalized anxiety disorder according to physical activity type in Korea adolescents: The Korea youth risk behavior web-based survey, 2020–2021

Objective This study aimed to analyze the association between the types of physical activity (PA) and the level of generalized anxiety disorder (GAD) in Korean adolescents. Methods This study analyzed data from the Korea Youth Risk Behavior Web-based Survey (KYRBS) for, 2020–2021. The dependent variable was the level of generalized anxiety disorder-7 (GAD-7). The GAD-7 scores were divided into four levels: normal, mild, moderate, and severe. The independent variables were moderate PA, vigorous PA, and strength exercises. Sex, school grade, body mass index, stress, depression, suicidal thoughts, violent victimization, drinking, smoking, substance abuse, sleep satisfaction, and sedentary time were selected as confounding variables. Results The independent variable and all confounding variables showed significant differences with the level of GAD-7 (all p &lt; .001). After adjusting for all confounding variables, we observed a 1.062 elevation in mild anxiety disorders, a 1.147 increase in moderate anxiety disorders, and a 1.218 increased incidence of severe anxiety disorders in the absence of vigorous PA. In the absence of strength exercises, there was a 1.057 elevation in mild anxiety disorders, a 1.110 increase in moderate anxiety disorders, and a 1.351 increased incidence of severe anxiety disorders. However, in the case of moderate PA, after adjusting for confounding variables, there was no significant association with GAD-7 levels. Conclusion To prevent anxiety disorders among Korean adolescents, the type of PA should be considered. Vigorous PA or strength exercises may help prevent GAD in Korean adolescents.

Suicide risk among racial minority students in a monoethnic country: A study from South Korea: Suicide risk among racial minority students

BackgroundSuicide is one of the leading causes of death among adolescents. Students from intercultural families (ICFs) are hypothesized to be vulnerable to suicide. This study aimed to identify the current status of depression and suicide in students from ICFs and the risk of suicide according to family type. MethodsData from the Korea Youth Risk Behavior Web-based Survey (KYRBS) were used for this study. We selected 586,829 participants from 2011 to 2020. We analyzed the statistical differences between groups using the chi-square and Bonferroni tests. Last, multiple logistic regressions were performed. ResultsRegarding experiencing extreme sadness/desperation and suicidal ideation, the group with both parents born outside Korea had the highest rate (37.1 % and 24.7 %, respectively), followed by the father-only, non-ICF, and mother-only groups. The both-parents group had the highest risk for suicidal plan and attempts, and for suicidal attempts after hospital visits (17.2 %, 14.9 %, and 59.5 %, respectively), followed by the father-only, mother-only, and non-ICF groups. In particular, the both-parents group had 1.74, 3.40, 4.56, and 6.44 times higher odds for suicidal ideation, suicidal plan, and suicidal attempt, and hospital visit after suicidal attempt than the non-ICF group, respectively. ConclusionsICF students were more vulnerable to suicide than the non-ICF group, particularly the both-parents and father-only groups. Thus, adolescents from ICFs are a high-risk group for suicide and should be a top priority for intervention.

Water intake and oral disease symptoms in adolescents: a cross-sectional study conducted in Korea in 2021

Objectives: Water constitutes a majority of the human body and is essential for health. In addition, water intake can prevent dental caries by improving salivary lubrication and self-cleaning. This study aimed to determine the relationship between the amount of daily water intake and the symptoms of oral disease in Korean adolescents. Methods: We used data from the Korea Youth Risk Behavior Web-based Survey (KYRBS), conducted in Korea in 2021, and identified the relationship between daily water intake and oral disease symptoms in Korean adolescents. KYRBS is a nationwide cross-sectional survey conducted by the Korea Disease Control and Prevention Agency (KDCA), and a total of 54,848 participants were included in this study. Results: After adjusting for confounding factors, logistic regression analysis showed that tooth pain was more often experienced by those who drank less than two cups of water per day (odds ratio [OR]: 1.14; 95% confidence interval [CI]: 1.01–1.30) than those who drank five or more cups of water per day. Conclusions: A low daily water intake is associated with tooth pain, a symptom of dental caries. The results of our study suggest that increasing water intake may reduce dental caries. Therefore, adequate water intake may help prevent dental caries.

Association between anti-smoking campaign types and smoking cessation attempts

ObjectiveThis study explored the association between anti-smoking campaign types and smoking cessation attempts. MethodsThis study included 4,594 individuals (3,292 male and 1,302 female) from the Korea Youth Risk Behavior Web-based Survey (KYRBWS) in 2018 and 2020. The methods of anti-smoking promotion were divided into online, offline, online and offline, and none. Attempts to quit smoking were classified as yes or no. Multiple logistic regression was performed to examine the association between antismoking campaign type and smoking cessation attempts. ResultsThose who saw anti-smoking advertisements both online and offline were found to have tried to quit smoking more than those who did not. (Online & offline: male, odds ratio [OR] 1.36; 95% confidence interval [95% CI], 1.08–1.71; female, OR, 1.75; 95% CI 1.21–2.54) In a subgroup analysis of the independent variables into which smoking cessation advertisements were subdivided, males were found to have the highest OR for smoking cessation attempts when they encountered advertisements in newspapers. (Newspaper: male, OR, 2.25; 95% CI, 1.00–5.02) Females had the highest OR for smoking cessation attempts when accessed via the Internet. (Internet: female, OR, 1.93; 95% CI, 1.07–3.50). ConclusionThis study showed that there is a correlation between smoking cessation advertisements and adolescents' smoking cessation attempts. The possibility of smoking cessation attempts is high when encountering smoking cessation advertisements both online and offline. Although offline smoking cessation advertisements have a great effect on adolescents’ smoking cessation attempts, it can be confirmed that the frequency of exposure for offline advertisements is less than that for online advertisements.

Health-Related Behavior and Psychosocial Characteristics of Adolescent Female Smokers in Korea, Compared with Adolescent Male Smokers.

This study aimed to investigate the relationship between health-related behavior and psychosocial characteristics among adolescent female smokers in South Korea using data from the 17th Korea Youth Risk Behavior Web-based Survey (KYRBWS) conducted in 2021. The analysis participants comprised 2407 adolescent smokers who were currently smoking, out of a sample of 54,835 participants. The characteristics of adolescent female smokers were examined by comparing them with those of adolescent male smokers. The results showed that male and female adolescent smokers accounted for 69.2% and 30.8% of the sample, respectively. Multiple logistic regression analysis identified school type, subjective socioeconomic status, physical activity, breakfast consumption, alcohol consumption, sexual experience, stress, generalized anxiety, and suicidal ideation as significant factors associated with adolescent female smokers. These findings provide important foundational data for the development of smoking-cessation programs and policies tailored specifically to adolescent female smokers.

A Study on the Factors Influencing Smoking in Multicultural Youths in Korea.

Based on the ecological integration model, this study examined the factors affecting smoking in adolescents from multicultural families by dividing them into two levels: microsystem and social network factors. The data were from the Korea Youth Risk Behavior Web-Based Survey (KYRBS) from 2016 to 2020. It included 4577 respondents whose fathers, mothers, or both, were not born in Korea. The factors affecting smoking among multicultural teenagers were determined by a composite-sample multiple logistic regression analysis. Male smoking rates among multicultural adolescents were 2.49 times higher than female rates in the microsystem. When the father was "Korean" rather than a "Foreigner", smoking was 0.55 times lower in family factors in terms of social network. In social factors of social networks, multicultural adolescents' smoking was 12.02 times greater when they were drinking than when they were not, and 3.62 times higher when the answer to the question of whether they had experienced violence was "yes" than "no." Based on the ecological model in this study, social factors such as drinking, and violence were highly related to smoking. Since multicultural adolescents were closely influenced by the surrounding environment, such as family, school, and social relationship, it was necessary to let parents and schoolteachers be involved in the intervention of smoking of multicultural adolescents so that they can help multicultural adolescents adjust better to school and perform better academically while decreasing risky behaviors for their health, such as drinking and, ultimately, smoking.

The Effects of Long-term Social Distancing on Sleep and Mood in Adolescents During the COVID-19 Pandemic

Background: School timings could influence teens' sleeping patterns by interrupting their sleep or the timing of light can shift their biological clock. The COVID-19 pandemic has altered teens’ sleeping schedule making it important to analyze the effects of long-term social distancing on adolescents’ sleep and mood. Objectives: This study analyzes the effects of long-term social distancing, due to the COVID-19 pandemic, on their sleeping patterns and mood. Methods: In this cohort study, data from the 2018 – 2020 Korea Youth Risk Behavior Web-based Survey (KYRBS) were used to compare teens’ sleep patterns in 2020 with those in 2018 – 2019. The primary outcomes of this study were the sleep duration and sleep time of adolescents throughout the week, between 2018 and 2019, and in 2020. The secondary outcomes were the teens’ mood, health perception, and sleep satisfaction, including differences in total sleep time and sleep discrepancies between weekends and weekdays. Results: Around 58 – 63 thousand students were surveyed each year, and the participation rate was 94.9 – 95.6%. After exclusion, 132,839 teens participated in the survey. From 2018–2020, the height and body weight of the participants did not change. After adjusting for participants’ sex and school year, it was found that more teens felt happy, fewer teens experienced sadness and desperation, and fewer teens had suicidal thoughts in 2020, compared with the previous two years. They also slept 10 minutes later (9.743 (95% confidence interval 7.954 - 11.530)), with wake-up times of 3 – 5 minutes later on weekdays (4.684 (3.449 - 5.919)). On weekends during social distancing, they slept 16 minutes later (15.721 (14.077 - 17.366)), with wake-up times of 12 minutes later (12.309 (10.393 - 14.225)). Although they slept five minutes less on weekdays (-5.059 (-6.817 to -3.301)) and three minutes less on weekends (-3.413 (-5.419 to -1.407)), their overall sleep satisfaction increased, and differences in sleep duration between weekdays and weekends decreased in 2020. Conclusions: During social distancing, the mood and sleep efficiency of teens improved. In the future, once the COVID-19 pandemic subsides, online classes can be included in the curriculum of school systems to ensure healthy sleep patterns in teenagers.

Trends in socioeconomic inequalities in obesity among Korean adolescents: the Korea Youth Risk Behavior Web-based Survey (KYRBS) 2006 to 2020.

This study investigated recent trends in the prevalence of obesity among Korean adolescents and explored socioeconomic disparities in obesity. This study used annual self-reported data on height, weight, and socioeconomic information from the Korea Youth Risk Behavior Web-based Survey from 2006 to 2020. With a 95.8% response rate, the sample consisted of 818,210 adolescents. Obesity prevalence was calculated according to 4 socioeconomic indicators (household income, father's educational attainment, mother's educational attainment, and urbanicity). Socioeconomic inequality was quantified using the relative index of inequality (RII). The overall prevalence of obesity increased, doubling from 5.9% in 2006 to 11.7% in 2020. Boys and high school students showed a higher prevalence. The RIIs in household income and parental educational attainments significantly increased with time, indicating a growing inequality in obesity. Socioeconomic disadvantages had a greater influence on obesity among girls. The most recent RII values for boys were 1.25 for income, 1.79 for the father's education, and 1.45 for the mother's education, whereas the corresponding values for girls were 2.49, 3.17, and 2.62, respectively. These findings highlight growing inequalities in adolescent obesity according to household income and parental educational attainments, especially for girls and middle schoolers.

17-year trends of body mass index, overweight, and obesity among adolescents from 2005 to 2021, including the COVID-19 pandemic: a Korean national representative study.

There is a lack of pediatric studies that have analyzed trends in mean body mass index (BMI) and the prevalence of obesity and overweight over a period that includes the mid-stage of the COVID-19 pandemic. Thus, we aimed to investigate trends in BMI, overweight, and obesity among Korean adolescents from 2005 to 2021, including the COVID-19 pandemic. We used data from the Korea Youth Risk Behavior Web-based Survey (KYRBS), which is nationally representative of South Korea. The study included middle- and high-school students between the ages of 12 and 18. We examined trends in mean BMI and prevalence of obesity and/or overweight during the COVID-19 pandemic and compared these to those of pre-pandemic trends in each subgroup by gender, grade, and residential region. Data from 1,111,300 adolescents (mean age: 15.04 years) were analyzed. The estimated weighted mean BMI was 20.48 kg/m2 (95% CI, 20.46-20.51) between 2005 and 2007, and this was 21.61 kg/m2 (95% CI, 21.54-21.68) in 2021. The prevalence of overweight and obesity was 13.1% (95% CI, 12.9-13.3%) between 2005 and 2007 and 23.4% (95% CI, 22.8-24.0%) in 2021. The mean BMI and prevalence of obesity and overweight have gradually increased over the past 17 years; however, the extent of change in mean BMI and in the prevalence of obesity and overweight during the pandemic was distinctly less than before. The 17-year trends in the mean BMI, obesity, and overweight exhibited a considerable rise from 2005 to 2021; however, the slope during the COVID-19 pandemic (2020-2021) was significantly less prominent than in the pre-pandemic (2005-2019). These findings enable us to comprehend long-term trends in the mean BMI of Korean adolescents and further emphasize the need for practical prevention measures against youth obesity and overweight.

Perceived household financial decline and physical/mental health among adolescents during the COVID-19 crisis: Focusing on gender differences

COVID-19 has worsened adolescents' mental and physical health. Several studies have reported that the effect may be greater in girls; however, relevant socio-ecological factors have not been examined. This study aimed to examine the factors associated with physical and mental health status among adolescents and the moderating role of gender on the relationship between physical and mental health status and perceived household financial decline. We analyzed the cross-sectional 2020 Korea Youth Risk Behavior Web-based Survey (KYRBS) collected between August and November 2020 in South Korea. It included 54,809 adolescents (28,269 males and 26,540 females), on average aged 15.1. We conducted ordinary least squares (OLS) regressions to examine the factors associated with physical and mental health outcomes. Gender differences were observed in associated factors. Then, we tested the moderating effect of gender by including an interaction term between gender and perceived household financial decline due to the COVID-19 pandemic. Perceived household financial decline due to COVID-19 negatively affected both groups. Perceiving moderate and severe financial decline due to COVID-19 is negatively associated with self-rated health among female adolescents than male counterparts. Female adolescents were also more vulnerable to mental health outcomes (i.e., distress, anxiety, and loneliness) when they perceived severe or moderate household financial decline due to COVID-19 compared to their male peers. Our findings suggest that female adolescents are more vulnerable to household financial shocks due to COVID-19, especially in households that have experienced a severe decline. We suggest the need for gender-sensitive policy interventions for adolescent mental health.

Estimated prevalence and trends in smoking among adolescents in South Korea, 2005-2021: a nationwide serial study.

Although smoking is classified as a risk factor for severe COVID-19 outcomes, there is a scarcity of studies on prevalence of smoking during the COVID-19 pandemic. Thus, this study aims to analyze the trends of prevalence of smoking in adolescents over the COVID-19 pandemic period. The present study used data from middle to high school adolescents between 2005 and 2021 who participated in the Korea Youth Risk Behavior Web-based Survey (KYRBS). We evaluated the smoking prevalence (ever or daily) by year groups and estimated the slope in smoking prevalence before and during the pandemic. A total of 1,137,823 adolescents participated in the study [mean age, 15.04years [95%confidence interval (CI) 15.03-15.06]; and male, 52.4% (95% CI 51.7-53.1)]. The prevalence of ever smokers was 27.7% (95% CI 27.3-28.1) between 2005 and 2008 but decreased to 9.8% (95% CI 9.3-10.3) in 2021. A consistent trend was found in daily smokers, as the estimates decreased from 5.4% (95% CI 5.2-5.6) between 2005 and 2008 to 2.3% (95% CI 2.1-2.5) in 2021. However, the downward slope in the overall prevalence of ever smokers and daily smokers became less pronounced in the COVID-19 pandemic period than in the pre-pandemic period. In the subgroup with substance use, the decreasing slope in daily smokers was significantly more pronounced during the pandemic than during the pre-pandemic period. The proportion of ever smokers and daily smokers showed a less pronounced decreasing trend during the pandemic. The findings of our study provide an overall understanding of the pandemic's impact on smoking prevalence in adolescents. Supplementary file2 (MP4 64897 KB).

National trends in physical activity among adolescents in South Korea before and during the COVID-19 pandemic, 2009-2021.

With the ongoing COVID-19 pandemic, several previous studies from different countries showed that physical activity (PA) decreased during the COVID-19 outbreak. However, few studies have examined the recent tendency of PA in the adolescent population. Thus, we aimed to investigate the long-term trend of PA in Korean youth and the prevalence changes between before and during the COVID-19 pandemic.Data from Korea Youth Risk Behavior Web-Based Survey (KYRBS) was collected for consecutive years between 2009 and 2021. The period was separated into prepandemic (2009-2019), early-pandemic (2020), and mid-pandemic (2021). Self-reported amount of PA was categorized into four groups (insufficient, aerobic, muscle strengthening, and both physical activities) according to World Health Organization (WHO)PA guidelines.A total of 840 488 adolescents aged 12-18 who fully responded to the survey were selected (response rate: 95.2%). The 13-year trends in the proportion of adolescents who reported aerobic and muscle-strengthening activities met or exceeded 2020 WHO exercise guidelines for adolescents plateaued (11.9% from 2009 to 2011, 14.2% from 2018 to 2019, 14.4% from 2020, and 14.0% from 2021); however, the slope decreased during the pandemic (βdiff , -0.076; 95% confidence interval [CI], -0.123 to -0.029). Proportion of sufficient aerobic exercise among adolescents sharply decreased midst the pandemic (28.0% from 2009 to 2011, 29.4% from 2018 to 2019, and 23.8% from 2020; βdiff , -0.266; 95% CI, -0.306 to -0.226) but increased again in 2021 (26.0% from mid-COVID 19; 95% CI, 25.4-26.7). Similar patterns were observed in Metabolic Equivalent Task (MET) score (MET-min/week; 804.1 from 2018 to 2019, 720.9 from 2020, and 779.6 from 2021). The mean difference in MET score between pre-COVID and post-COVID was -55.4 MET-min/week (95% CI, -70.5 to -40.3).Through a nationwide representative study, there was no significant difference with regard to the number of Korean adolescents who achieved the PA guidelines (preand postpandemic); however, the prevalence of recommended levels of PA needs to increase more based on the trend before the COVID-19 outbreak. The findings of this study suggest reinforcement of the importance of public health policies for Korean youths to be more physically active, especially during and after the pandemic.

S-25-3: TRENDS IN SOCIOECONOMIC INEQUALITIES IN OBESITY AMONG KOREAN ADOLESCENTS: THE KOREA YOUTH RISK BEHAVIOR WEB-BASED SURVEY (KYRBS) 2006 TO 2020

Objective: Studies reported the plateau of the rates of adolescent obesity and its masked socioeconomic inequality in developed countries. However, the burden of pediatric obesity continued to increase in Korea and its socioeconomic disparity remains poorly described. This study aims to investigate the recent trends of prevalence and socioeconomic disparity in obesity among Korean adolescents from 2006 to 2020. Design and method: We used annual data of self-reported height, weight, and socioeconomic information from the nationwide survey, Korea Youth Risk Behavior Web-based Survey (KYRBS), from 2006 to 2020. Adolescent obesity was defined as a sex-specific BMI for age of 95 percentile or greater among children aged between 12 and 19 years. Obesity prevalence was calculated according to each of four socioeconomic indicators (household income; parental education attainment; urbanicity). Also, socioeconomic inequality in it was quantified and compared using Relative Index of Inequality (RII). Identical analyses were repeated for the subgroups by sex or stage of school along with the total study population. The trend analyses of prevalence and inequalities were conducted using linear regression model with the variable of survey year. Results: The analytic sample consisted of 818,210 students, representing approximately 64% of adolescents in Korea. The overall prevalence of obesity continued to increase and doubled during the study period. Male and high school students showed higher absolute figures. Inverse relationships between obesity and socioeconomic status were observed across all subgroups. RIIs in household income and parental education attainments significantly increased with time. These socioeconomic disadvantages exercised greater influence on obesity among female and middle school students. Conclusions: This study showed increasing prevalence and widening inequality in obesity among Korean adolescents. These findings highlight parental educational attainments to understand socioeconomic disparities in adolescent obesity, along with household economic status. Relevant policymaking and intervention should focus on not only lowering the absolute figures among boys and high school students but also narrowing the gap among the disadvantaged girls and middle school students.

Effect of Increased Depressive Feelings during the COVID-19 Pandemic on the Association between Depressive Mood and Suicidal Behavior: Using the 17th (2021) Korea Youth Risk Behavior Web-Based Survey (KYRBS).

This study investigated the impact of increased depressive feelings during the COVID-19 pandemic on the suicidal behavior of Korean high school students using the 17th Korea Youth Risk Behavior Web-Based Survey (KYRBS). We classified the independent variables into four groups ("no depressive mood and no increase in depressive feelings [group A]", "no depressive mood and increase in depressive feelings [group B]", "depressive mood and no increase in depressive feelings [group C]", and "depressive mood and increase in depressive feelings [group D]"). Compared to group A, group D showed an odds ratio of 18.30 in men and 14.87 in women for suicidal behavior after accounting for demographic and health behavioral characteristics. We found that depressive mood and a relatively short-term increase in depressive feelings had a synergistic effect, rather than an additive one, on suicidal behavior. Based on this result, we claim that an appropriate intervention method is necessary to prevent adolescents' depressive mood from developing into suicidal behavior during the pandemic.

Factors associated with adolescents’ sexual experience based on the biopsychosocial model: a cross-sectional study using the Korea Youth Risk Behavior Web-based Survey (KYRBS)

ObjectivesSexual activity is an important integrative behaviour that interacts with biological, psychological and social factors among various changes in adolescence. However, starting sex at an early age is associated with...