Problematic Internet use and its associations with health-related symptoms and lifestyle habits among rural Japanese adolescents

Aim There have been concerns about the increase in problematic Internet use (PIU) and its impact on lifestyle habits and health-related symptoms, given the rapid spread of smartphones. This study aimed to clarify PIU prevalence over 3 years in the same area and investigate lifestyle and health-related factors related to PIU among junior high-school students in Japan. Methods Each year during 2014-2016, a survey was conducted with junior high-school students from a rural area of Japan (2014, n = 979; 2015, n = 968; 2016, n = 940). Young's Internet Addiction Test was used to assess participants' PIU. Students scoring 40 or higher on the Internet Addiction Test were classified as showing PIU in this study. The associations between PIU and lifestyle factors (e.g., exercise habits, weekday study time, and sleep time) and health-related symptoms (depressive symptoms and orthostatic dysregulation [OD] symptoms) were studied by logistic regression analyses. Results Over the 3 years, the prevalence of PIU was 19.9% in 2014, 15.9% in 2015, and 17.7% in 2016 without significant change. PIU was significantly associated with skipping breakfast, having a late bedtime (after midnight), and having OD symptoms among students from all grades. Sleepiness after awakening in the morning, less studying time, and depressive symptoms had significant positive associations with PIU, except among 1st grade junior high-school students. Conclusion Our results suggest that PIU is related to decreased time spent sleeping, studying, and exercising and increased symptoms of depression and OD. Further investigations are needed to develop preventive measures for PIU.