Interoception, Self-Injury and Suicidal Ideation in Female Adolescents With Restrictive Eating Disorders and Co-Morbid Borderline Personality Disorder

Aims: Both restrictive eating disorders (REDs) and borderline personality disorder (BPD) are characterised by a higher risk of self-injury and suicidal ideation; however, the possible role of altered interoception in modulating such risk is poorly understood. We set out to conduct a clinical study to explore the relationship between interoception, self-injury and suicidal ideation in patients with REDs and BPD. Methods: We recruited a sample of 75 female adolescents affected by REDs, of whom 21 had co-morbid BPD. In addition to collecting comprehensive demographic and clinical data, we administered the Multidimensional Assessment of Interoceptive Awareness Version 2 (MAIA-2) to all patients. Results: The risk of nonsuicidal self-injury was predicted by co-morbid BPD (p < 0.001), lower scores on the MAIA-2 'trusting' subscale (p = 0.033) and higher scores on the 'not-distracting' subscale (p = 0.027). The risk of suicidal ideation was predicted by co-morbid BPD (p < 0.001), lower scores on the MAIA-2 'trusting' subscale (p = 0.039), and higher scores on the 'not-distracting' (p = 0.005) and 'self-regulation' (p = 0.011) subscales. Conclusions: The presence of co-morbid BPD, together with mistrust in body sensations and heightened emotional reaction and attentional response to interoceptive sensations, can increase the risk for both self-injury and suicidal ideation in female adolescents with REDs. Higher awareness of mind-body integration appears to further increase the risk for suicidal ideation only.