JMIR Publications

ABSTRACT

Background:

Non-suicidal self-injury(NSSI) is now recognized globally as a major public health issue among adolescents and young adults.

Objective:

In this study, we aim to explore 1)whether chronotype moderate the risk of NSSI by BMI; 2)whether self-esteem is a mediator of this relationship.

Methods:

In May-June 2022, a multi-stage cluster sampling method was used to obtain adolescents from the 4th grade college students, and a follow-up of participants at baseline was conducted six months later, excluding ineligible groups, and finally 1772 participants were included. We measure the chronotype, self-esteem and NSSI. The primary exposure was BMI and the primary outcome was NSSI; while the moderator were chronotype and self-esteem. Multivariable linear regression model and Chi-square analysis were performed to assess associations of of BMI, chronotype and self-esteem against NSSI status. Moderation analysis was employed by PROCESS method to explore the relationship between these variables.

Results:

A total of 1772 adolescents were finally included. The mean age was (20.53±1.65) years old in baseline. Multivariable linear regression suggest that the high level BMI (β=0.056, 95%CI: 0.008-0.086) has been shown to be associated with higher NSSI. There is also the interaction between BMI, chronotype and NSSI. In the relationship between BMI and NSSI, chronotype played a moderator mediator role, and self-esteem played a mediator role, respectively.

Conclusions:

Early control of BMI is important for identifying potential risk factors for NSSI, and evaluate how to improve the impact of self-esteem on NSSI in adolescents from multiple perspectives.