Emotion regulation difficulties and experiential avoidance in adolescents with non-suicidal self-injury: a latent profile and moderation analysis

Background Non-suicidal self-injury (NSSI) represents a significant clinical concern among adolescents. Although emotion regulation difficulties (ERD) and experiential avoidance are associated with NSSI, how these regulatory vulnerabilities co-occur within individuals and whether experiential avoidance influences the ERD–NSSI association remain unclear. This study aimed to characterize regulatory vulnerability profiles based on ERD and experiential avoidance and examine the moderating role of experiential avoidance in adolescent NSSI. Methods The study included 456 adolescent psychiatric inpatients with NSSI ( M age = 15.30, SD = 1.66). Participants completed self-report measures assessing ERD, NSSI, and experiential avoidance, including the Difficulties in Emotion Regulation Scale (DERS), Adolescent Non-suicidal Self-Injury Assessment Questionnaire (ANSAQ), and Acceptance and Action Questionnaire-II (AAQ-II). Anxiety and depressive symptoms were assessed using clinician-administered Hamilton Anxiety Rating Scale-14 (HAMA-14) and Hamilton Depression Rating Scale-17 (HAMD-17) ratings conducted by trained psychiatric clinicians. Latent profile analysis was conducted to identify profiles based on ERD and experiential avoidance. The Bolck-Croon-Hagenaars (BCH) method was used to compare depressive symptoms, anxiety symptoms, and NSSI severity across profiles. Moderation analysis was conducted to examine whether experiential avoidance modified the strength of the association between ERD and NSSI. Results LPA identified three profiles characterized predominantly by low (23.25%), moderate (42.54%), and high (34.21%) levels of regulatory vulnerability. BCH analysis identified significant profile differences in NSSI, depression, and anxiety. NSSI and anxiety showed graded differences across profiles, while depressive symptoms were elevated in both Moderate and High profiles. Experiential avoidance showed a modest moderating effect on the association between ERD and NSSI ( B = 0.005, 95% CI = [0.001, 0.008]), indicating that the strength of this association differed across levels of experiential avoidance. Conclusion Latent profiles of ERD and experiential avoidance were identified among adolescents with NSSI, with differences in clinical burden across profiles. Experiential avoidance modestly moderated the association between ERD and NSSI, with the magnitude of this association varying across levels of experiential avoidance. These findings provide complementary person-centered and variable-centered perspectives on regulatory vulnerability among adolescents with NSSI.