Understanding Comorbidity Between Non-Suicidal Self-Injury and Depressive Symptoms in a Clinical Sample of Adolescents: A Network Analysis

Abstract

Background

Non-suicidal self-injury (NSSI) and depression often co-occur among adolescents with more severe clinical symptoms. This study examined the network structures of NSSI and depressive symptoms in adolescents.

Methods

Participants were recruited in the psychiatric outpatient clinics of three tertiary hospitals between April 10 and July 10, 2023. All participants been already found with self-injury behaviors in outpatient when enrolled. NSSI diagnostic criteria and Patient Health Questionnaire-9 (PHQ-9) were utilized to collect NSSI and depressive symptoms separately. We performed a network analysis to visualize the correlation between each symptom and to identify core and bridging symptoms in comorbidities.

Results

A total of 248 patients were enrolled in the study, with a mean age of 15.48 (SD = 1.62). Based on the PHQ-9 scores and grades, our results showed that the incidence of depression in adolescents with non-suicidal self-injury behavior was relatively high (N=235, 94.76%), with the majority having severe depression. The network analysis revealed that nodes D-6 “feeling bad, failing or letting yourself or your family down”, D-1 “little interest or pleasure” and D-4 “feeling tired” were the most vital and most central symptoms. The most crucial bridging symptom is the node NSSI-8 “frequent thinking about self-injury”, which connects the NSSI to the depression comorbid network.

Conclusion

This study offers a significant symptom-level conceptualization of the association between NSSI and depressive symptoms in a clinical sample of adolescents, which not only enhances our understanding of the comorbid but also identifies potential treatment targets to prevent and treat comorbidity between adolescent NSSI and depression.

Keywords:

• non-suicidal self-injury
• depression
• comorbidity network
• bridge symptoms
• network analysis

Ethics Approval

This study was approved by the Ethics Committee of Second Affiliated Hospital of Zhejiang University School of Medicine [Grant No. (2023-0822)] and other participating hospitals. This study was conducted in accordance with the ethical standards of the Helsinki declaration.

Acknowledgments

The authors are grateful to the adolescents who participated in this research and to the hospitals and research assistants who facilitated data collection.

Author Contributions

All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.

Disclosure

The authors have no conflicts of interest to declare.

Additional information

Funding

This research received no external funding.