Predicting adult mental health from non-suicidal self-injury in adolescence: a prospective study spanning 2007–2023

Abstract

This study examined associations between adolescent non-suicidal self-injury (NSSI) and adult mental health within a cohort of school students who answered questionnaires in 2007 (T1: N = 992, Mage = 13.7, 50.1% girls) and 2008 (T2: N = 987, Mage = 14.9, 50.9% girls), with follow-ups in 2017 (T3: N = 557, Mage = 25.3, 58.7% women) and 2023 (T4: N = 386, Mage = 29.9, 63.0% women). Attrition was accounted for with sample weighting and mixed modelling, and robust estimates balance for residual non-normality. Significant declines in any NSSI (≥ 1 instance) and repetitive NSSI (≥ 5 instances) were observed between T2–T3 (any NSSI: 43–19%; repetitive NSSI: 21–10%; p