Association between sleep disturbance and mental health status among adolescents: A longitudinal study of Japanese junior high school students

A limited number of longitudinal studies have addressed the association between sleep disturbance and mental health status among adolescents. To examine whether each of these is a risk factor for the onset of the other, we conducted a prospective longitudinal cohort study of Japanese junior high school students. In 2004, we performed a baseline study of students attending three junior high schools in Tokyo, and in 2006, a follow-up study was performed on the same population. The Pittsburgh Sleep Quality Index was used to evaluate sleep disturbance, and the 12-item General Health Questionnaire was used to evaluate mental health status.

The subjects were 698 students, of whom 516 were suitable for analysis. The incidence of newly developed poor mental health status during the 2 years leading to the follow-up study was 35.1%. New onset of poor mental health status was significantly associated with new onset of sleep disturbance and lasting sleep disturbance. The incidence of sleep disturbance during the 2 years leading to the follow-up study was 33.3%. New onset of sleep disturbance was significantly associated with new onset of poor mental health status and lasting poor mental health status.

Sleep disturbance and poor mental health status each increase the other's onset risk. An understanding of the close association between sleep disturbance and mental health status is required in order to devise future mental health policies for adolescents.