Relationships between the frequency and severity of non‐suicidal self‐injury and suicide attempts in youth with borderline personality disorder

Abstract

Non-suicidal self-injury (NSSI) is a recognized indicator of suicide risk. Yet, the ubiquity of this behaviour in borderline personality disorder (BPD) limits its utility as a predictor of risk. Consequently, this study aimed to elucidate the relationship between other features of NSSI, including frequency and severity, and suicide attempts. Participants included 107 youth (15 to 25 year olds) with BPD who were assessed for BPD severity, depressive symptoms, 12-month frequency of NSSI and suicide attempts, as well as the levels of treatment sought following each self-harm event. Three-quarters (75.7%) of youth with BPD reported NSSI and two-thirds (66.4%) reported a suicide attempt over the previous 12 months. The frequency of NSSI over the previous 12 months did not show a linear or quadratic relationship with the number of suicide attempts when adjusting for severity of depression, impulsivity and interpersonal problems. NSSI severity was not associated with more frequent suicide attempts. Only impulsivity and depression were uniquely predictive of suicide attempt frequency. A relative increase in the frequency and severity of NSSI occurred in the months prior to a suicide attempt. The prevalence of NSSI and suicide attempts among youth presenting for their first treatment of BPD appear to be perilously high, considerably higher than rates reported by adults with BPD. Findings suggest that clinicians should give more weight to average levels of impulsivity and depression, rather than the absolute frequency and severity of NSSI, when assessing for risk of suicide attempts. Notwithstanding this, a relative increase in the frequency and severity of NSSI appears to be predictive of a forthcoming suicide attempt.