Smartphone Addiction and Sleep Quality Associated with Depression in University Students in Japan

Abstract

Smartphones have developed rapidly in recent years, with their use becoming widespread and an established part of daily life. Along with the development of various applications, smartphone addiction or dependence has been routinely reported, and indicated to be associated with such conditions as sleep problems and depression. In order to examine the relationships of smartphone use, sleep quality, chronotype, and physical exercise, with a depressive state, the authors administered a self-reporting questionnaire survey, which included the Japanese version of the Smartphone Dependence Scale (J-SDS), the Pittsburg Sleep Quality Index (PSQI), the Morningness-Eveningness Questionnaire (MEQ), and the Beck Depression Inventory (BDI), to 119 university students in Japan. Results of multivariate logistic regression analysis indicated that scores for the J-SDS and PSQI were significantly related to BDI score. These findings suggest that smartphone addiction and poor sleep quality are associated with the depressive state in students in Japan.