The association between internet usage and sleep problems among Japanese adolescents: three repeated cross-sectional studies.

Study objectives Sleep problems and problematic internet use have important implications for adolescent health; however, there have been no large-scale surveys using comprehensive measures. We examined the association between internet use duration and sleep problems among Japanese adolescents. Methods We used data from the Lifestyle Survey of Adolescents collected in 2012, 2014, and 2017. We calculated the change in sleep status (insomnia, sleep duration, bedtime, and sleep quality) and internet usage (screen time and services such as internet surfing, social media use, streaming such as YouTube, and online gaming). A binary logistic model was estimated for insomnia. Generalized ordered logit models were employed for the ordinal outcomes (sleep duration, bedtime, sleep quality, and multidimensional sleep health). Sampling weights were constructed based on participation rate on survey years and selection rates from population statistics. Results We analyzed data from 248,983 adolescents. Sleep status was unchanged; however, many adolescents used more internet services and for longer durations. The odds ratio of internet screen time for all sleep problems (insomnia, shorter sleep duration, later bedtime, and worse sleep quality) gradually declined. Longer internet screen time (> 5 hours) was strongly associated with all sleep problems. Internet services were also associated with sleep problems; particularly, social media use and online gaming were linked to later bedtimes. Conclusions Despite the decreased strength in the association between internet usage and sleep problems, longer internet time was strongly associated with sleep problems. Public health interventions should consider internet use as an intervention target to improve adolescents' health.