Nonsuicidal self-injury risk factors among adolescents in Japan: A population-based study

Few researchers have explored the prevalence and impact of risk factors of nonsuicidal self-injury (NSSI) in community-dwelling Japanese adolescents. We used a survey to assess NSSI-associated factors; somatic symptoms; and sleep, psychiatric, and eating problems in a sample of 1,840 Japanese 8th grade students. Associations were examined via logistic regression analyses. Among the students, 34.6% engaged in either self-hitting or self-cutting. A significant association was found between abdominal pain, sleep disturbance, conduct issues, and eating problems on one hand, and self-hitting without self-cutting as well as self-cutting with or without self-hitting on the other. Emotional problems were associated with self-hitting, and headaches and peer relationship problems were associated with self-cutting. Participants who engaged in both self-cutting and self-hitting reported more headaches and conduct problems than those who engaged only in self-cutting, suggesting a greater level of mental disturbance in these adolescents. These problems should be given serious attention by clinicians when evaluating adolescents regarding the presence of NSSI.