Association between Systemic Immune-Inflammation Index and Self-Harm Behavior: A Scoping Review
DOI:
https://doi.org/10.26911/jepublichealth.2026.11.03.10Abstract
Background: Emerging evidence suggests that systemic inflammation may contribute to the pathophysiology of depression and self-harm. This study aims to map the scientific evidence regarding the relationship between Systemic Immune-Inflammation Index (SII) as a readily available biomarker and self-harm behavior across various populations and clinical contexts, while identifying patterns of findings, methodological variations, and existing research gaps.
Subjects and Method: This research employs a scoping review methodology based on the Arksey and O’Malley framework and reported in accordance with the PRISMA Extension for Scoping Review. Literature was sourced from databases such as PubMed and ScienceDirect. Seven studies were included in the final synthesis and the critical appraisal of the selected papers followed the Joanna Briggs Institute (JBI) guidelines.
Results: Higher SII levels were consistently associated with increased suicide risk, particularly in treatment-naïve and first-episode Major Depressive Disorder (MDD) populations. Adolescents with co-occurring NSSI and SA demonstrated the most pronounced inflammatory profiles, whereas findings were less consistent in isolated NSSI or SA groups.
Conclusion: Current evidence suggests that SII may have potential utility as an adjunctive biomarker for self-harm risk stratification and its clinical utility remains limited by moderate predictive accuracy and methodological heterogeneity.
Keywords:
biomarker, systemic immune-inflammation index, self-harm, suicide attempt
How to Cite
References
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