(PS3-A4) Exploring the Interaction Between Borderline Symptoms and Interpersonal Constructs Associated with Suicide Risk

Background: The Interpersonal Theory of Suicide illustrates a link between suicide risk (SR) and the interpersonal constructs of thwarted belongingness (TB; feeling as if one does not belong in their social environment) and perceived burdensomeness (PB; feelings of being a burden). Borderline Personality Disorder (BPD) symptomatology is also associated with SR, although, it is unclear whether BPD symptoms interacting with TB/PB can help identify SR. In this study, we hypothesized that BPD symptoms, TB, and PB would each be positively related to SR; further, we explored whether BPD symptoms moderate the relationships between TB+SR and PB+SR such that that those with elevated TB/PB and BPD will have the highest SR.

Methods: Non-treatment-seeking adults (N=92) ages 18-70, with varied history of suicide, depression, and anxiety from an ongoing study, The Neurobiology of Suicide (NCT02543983), completed the Interpersonal Needs Questionnaire-15 (measuring TB and PB) and the Borderline Symptom List-23 (measuring BPD symptoms).  Participants were categorized as lower SR for scores of 0 (n=75) or higher SR for scores 1-5 (n=17) based on 24-hour Columbia-Suicide Severity Rating Scale Ideation Scores. We used logistic regression to test our hypotheses.

Results:  As expected, PB (odds ratio=1.1, p= 0.008) and BPD symptoms (odds ratio = 1.06, p= 0.001) were both positively associated with SR, though TB was not.  The moderating effect of BPD symptoms on PB was a trend (p=0.054) suggesting higher BPD scores attenuating the PB/SR relationship, contrary to our hypothesis.

Discussion: Results are consistent with previous literature showing that BPD symptoms and PB relate to higher SR, although TB appears to not correlate with SR. The findings do not support the hypothesis that BPD symptoms moderate the relationship between PB and SR, though more data are needed. The individual and conjoint effects of PB and BPD symptoms warrants further research to improve identification of individuals at highest SR.