Association between sedentary behavior and depression among South Korean adolescents

The symptoms and outcomes of depressed mood are considered severe social issues among Korean adolescents. However, it is difficult to detect depressed mood and evaluate the factors associated with suicide among such individuals. Identifying the risk factors of depressed mood would allow for improved perspectives for interventions. Therefore, in this study, we investigated the association between sedentary behavior and the prevalence of depressed mood.

From 2014 to 2020, the Korea Youth Risk Behavior Survey (KYRBS), which is a web-based self-report survey, was used for analysis. A total of 366,405 individuals participated in this study. Sedentary behavior was divided into 3 groups based on the duration of sedentary behavior: low sedentary time group (LS, 25 percentile), middle sedentary time group (MS, from 25 to 75 percentile, reference), and high sedentary time group (HS, above 75 percentile). Further, sedentary behavior is divided into 4 subgroups based on weekdays or weekends and owing to studying or non-studying. The chi-square test and multivariate logistic regression were used in this study.

Compared to the MS, which is the reference, male participants in both the LS and HS had experienced depressed mood (adjusted odds ratio (OR): 1.035, 95% CI = 1.003-1.068 in the LS, adjusted OR: 1.091, CI = 1.055-1.129 in the HS). Among females, only the HS was statistically significant (adjusted OR: 1.039, 95% CI = 1.011-1.069 in HS). Korean adolescents with longer sedentary durations during weekdays regardless of the cause of sedentary behavior are positively associated with depressed mood with suicidality in the HS for both genders.

This study found a positive association between the prevalence of depressed mood and sedentary behavior, and it focused on the cause and timing. Interventions targeting sedentary behavior could be effective in reducing depressed mood and suicidality among adolescents.