Autistic Traits Are Associated with Suicidal Thoughts and Behaviors Among Patients with Borderline Personality Disorder

<b>Background:</b> Borderline personality disorder (BPD) is a pervasive mental health condition characterized by a heightened risk of suicidal behavior. Emerging research has suggested a potential overlap between BPD and subthreshold autistic traits (ATs), raising the possibility that these traits may influence the development, course, and severity of BPD, particularly in relation to suicidal ideation and behaviors. This study aims to evaluate the relationship between suicidal ideation, suicidal behaviors, and ATs in individuals with BPD. <b>Methods:</b> We assessed 106 subjects with BPD using the mood spectrum self-report version (MOODS-SR) of the Adult Autism Subthreshold Spectrum (AdAS Spectrum) questionnaire. The sample was divided into three groups based on suicidal ideation and behaviors. Non-parametric tests compared AdAS Spectrum scores, while Spearman's correlation assessed the relationships between AdAS Spectrum scores and suicidality. Logistic regression analyses were conducted to identify predictive AdAS Spectrum domains for suicidal ideation and behaviors. <b>Results:</b> Subjects with suicidal behaviors and suicidal ideation showed significantly more autistic features than non-suicidal subjects. Correlation analysis revealed that all AdAS Spectrum domains, except empathy, were significantly correlated with both suicidal ideation and behaviors, with stronger correlations for suicidal behaviors. Moreover, restricted interests, rumination, and sensory sensitivity emerged as significant predictors of suicidal ideation, while the lack of empathy was a significant predictor of suicidal behavior. <b>Conclusions:</b> Our results confirm a strong correlation between the presence of ATs and suicidality in subjects with BPD, in particular highlighting rumination, altered sensitivity, and empathic deficits as specific predictors of suicidal thoughts and behaviors.