Affective theory of the mind and suicide in women with borderline personality disorder and schizophrenia: A comparative study

Background
Theory of mind (ToM) is one of the essential components of social cognition. Affective ToM enables us to interpret other’s feelings and behaviors. Borderline personality disorder (BPD) and schizophrenia are two distinct mental disorders, yet they have a mutual deficit in interpreting emotions, thoughts, and intentions which may lead to a higher incidence of suicidality. Studies that involved social cognition, particularly ToM in schizophrenia, or BPD have controversial results. Therefore, this study aimed at comparing affective ToM functioning in female patients with BPD, schizophrenia, and healthy controls. In addition, identifying the possible impact and any correlation exists between the affective ToM and liability for suicide in those patients. Sixty individuals were recruited from the Institute of Psychiatry, Ain Shams University, Cairo, Egypt, and assigned into 3 groups where group A involved 20 BPD patients, group B involved 20 schizophrenic patients, and group C were healthy persons as a control. Assessment of affective ToM was done using Reading the Mind in the Eyes Test (RMET), and probability of suicide was measured using Suicide Probability Scale (SPS).

Results
Regarding ToM, the three groups were assessed using RMET and the results revealed a significantly higher mean score (hypermentalization) in BPD patients than both schizophrenic patients and controls. While schizophrenic patients had significantly lower mean scores than the control group (hypomentalization). As well, BPD patients had a significantly higher suicide probability total score than Schizophrenic patients and in all subdomains except for the hostility subdomain that was significantly higher in schizophrenic patients. Interestingly, in BPD, the suicide probability total score was positively correlated with RMET.

Conclusions
BPD patients have enhanced affective ToM and hypermentalization that is significantly associated with increased suicide probability in those patients, while in schizophrenia, hypomentalization could not be linked to increased suicide probability. Rehabilitation and proper management of ToM abnormalities might be a crucial tool in suicide prevention in mental illnesses, particularly, BPD.