Excessive gaming and social media are associated with depressive symptoms among junior high school students in Japan.

Background: The rapid increase in depression among adolescents is an urgent concern. This study examined the association between depression and digital device use, among adolescents. Furthermore, we explored the time thresholds of specific digital device use.

Methods: This cross-sectional study administered self-reported questionnaires to all 467 students of a junior high school in Japan. The Patient Health Questionnaire-9 was used to assess depression (cut-off values 0-4: no or minimal, 5-9: mild, 10-27: moderate to severe). Data on participants' dietary habits, sleep habits, physical activity, and time spent on digital devices (total, gaming, social media, and video watching) were obtained. Multiple logistic regression analysis was used to examine the abovementioned association.

Results: The response rate was 92.9% and data from complete case analyses with 357 participants were analyzed. Of the participants, 11.8% reported depressive symptoms. Lifestyle factors and digital device use were consistently associated with depression. Total time spent on any digital device was not significantly associated with depression, adjusted for selected lifestyles. However, ≥3 h of gaming (Adjusted odds ratio [AOR] 3.32 [95%CI, 1.66-6.65], p = 0.001) and social media use (AOR 2.56 [95%CI, 1.28-5.11], p = 0.008) on non-school days were significantly associated with depression, regardless of adjustment.

Conclusion: Moderate use of digital technology to avoid disrupting lifestyles is desirable for adolescents' mental health. Furthermore, gaming or social media use for ≥3 h was consistently significant factors. Health education to control these factors for <3 h is favorable to maintain mental health.