Longitudinal trajectories of non-suicidal self-injury, suicidal ideation, and suicide attempts following standardized outpatient emergency management in adolescents

Background Emergency presentations for non-suicidal self-injury (NSSI), suicidal ideation, and suicide attempts in youth have increased markedly. Behavioural and ideational components of self-injury and suicidality may follow partially dissociable courses, underscoring the need for longitudinal evaluation after emergency care. Objectives To examine longitudinal changes in NSSI behaviour, NSSI thoughts, suicidal ideation, and suicide attempts after standardized outpatient emergency management; identify psychological and familial predictors; and assess the perceived benefit of safety planning. Methods Participants were 105 adolescents (mean age = 14.9 years) presenting in acute crisis to an outpatient emergency service with NSSI and/or suicidal ideation/suicide attempt, followed up twice. Measures included NSSI and suicidal thoughts and behaviour, emotional reactivity, psychological distress, patient and parental motivation, parental stress, and perceived benefit of the safety plan. Changes over time were analysed using non-parametric tests of both frequency and prevalence, and predictors using linear mixed-effects models. Results Changes differed by dimension: suicide attempts declined in both frequency and prevalence, NSSI behaviour declined in frequency, and NSSI thoughts and suicidal ideation in prevalence while overall frequency was unchanged. Emotional reactivity, general psychological distress, and patient motivation improved. Higher patient motivation was independently associated with lower NSSI behaviour over time, while no variables significantly predicted NSSI thoughts. Parental, but not adolescent, perceived benefit of the safety plan was associated with reduced NSSI behaviour at follow-up. Conclusions Following emergency management, self-injurious behaviour and ideation followed partially dissociable courses. Behavioural improvement was linked to adolescent motivation and parental engagement, whereas ideation improved less completely: fewer adolescents reported suicidal or NSSI-related thoughts, but their frequency did not decline. Ideation therefore warrants continued, targeted monitoring even when behaviour improves.