Self-harm, Suicide, and ICD-11 Complex Posttraumatic Stress Disorder in Treatment-Seeking Adolescents with Major Depression.

Posttraumatic stress disorder (PTSD) is linked with self-harm and suicide, but few studies have examined these severe outcomes in relation to complex trauma. This study examined the associations between self-harm and suicide-related phenomena with ICD-11 complex PTSD (CPTSD) among treatment-seeking youths. A convenience sample of 109 adolescents with major depression (69.7% female; mean age = 15.24) were recruited from an outpatient psychiatric clinic. Participants completed measures for ICD-11 CPTSD, adverse childhood experiences (ACEs), self-harm behaviors, and past-year history of four suicide-related phenomena. Relationships between each self-harm and suicide-related variable with CPTSD were assessed at the symptom and diagnostic levels. Participants reported an average of three ACEs; 33.9% met diagnostic requirements for ICD-11 CPTSD. Past-year suicidal thought and attempt, but not self-harm, significantly associated with CPTSD status. At the symptom level, self-harm associated with CPTSD total symptom and all symptom clusters scores, with strongest associations found with symptoms of negative self-concept. CPTSD total symptom scores also associated strongly with past-year history of suicidal thought, plan, and attempt; the three core PTSD symptom clusters scores consistently and strongly linked with these suicide-related phenomena. For symptoms of complex trauma, relationship disturbances associated with having a suicide attempt, and negative self-concept associated with both having a plan and an attempt. Assessing and targeting ICD-11 CPTSD symptoms have potential to reduce self-harm and suicidality in young people experiencing mental distress, particularly for those with a trauma history and regardless of whether they meet criteria for a diagnosable trauma response.