Reward reactivity in non-suicidal self-injury in adolescents: protocol for a longitudinal study

<title>Abstract</title> Background The high incidence and serious consequences of non-suicidal self-injurious (NSSI) behaviors in adolescents warrants the attention of medical professionals, sociologists, and educators. Evidences of enhanced reward reactivity have been observed in adolescents NSSI as well as those with suicidal risks. It is hypothesized(1) that elevated reward reactivity toward general rewards may increase the risk of suicide. To test the hypothesis, a cohort study has been designed to systematically evaluate the reward reactivity in combination of other risk factors commonly reported in NSSI adolescents, with follow-up for at least 24 months. Methods This protocol is for a longitudinal cohort study that aims to enroll over three hundred and twenty patients with NSSI at the Affiliated Kangning Hospital of Ningbo University. The main outcome would be the psychological well-being, as well as the suicidal attempt during the 24- month follow-up. Clinical information, pathopsychological evaluation and brief cognitive assessment would be collected at the baseline. Reward reactivity will primarily be tested in behavioral tasks under functional magnetic resonance imaging, accompanied with the assessment of the traits of reinforcement. Discussion This study proposes a highly integrative, multimodal investigation of the neurobiological and systemic inflammatory pathways underlying NSSI in Chinese adolescents with MDD, with a central focus on reward circuit dysfunction. Ethics and dissemination Ethics and dissemination have received ethics approval from the Ethics Committee of the Affiliated Kangning Hospital of Ningbo University(Approval Number: NBKNYY-2023-LC-46). The study is currently recruiting participants. Written informed consent is obtained from all participants and their legal guardian. The findings will be published in peer-reviewed journals and presented at relevant conferences. A short report will be provided to policy makers and patient groups. Trial registration This study is registered in https://www.medicalresearch.org.cn/ under protocol registration number ID: ChiCTR2500107121. Recruitment started in September, 2023. The version of this protocol is v1.0.