Characteristics and stability of hallucinations and delusions in patients with borderline personality disorder

Background: Psychotic features have been part of the description of the borderline personality disorder (BPD) ever since the concept “borderline” was introduced. However, there is still much to learn about the presence and characteristics of delusions and about the stability of both hallucinations and delusions in patients with BPD. Methods: A follow-up study was conducted in 326 BPD outpatients (median time between baseline and follow-up = 3.16 years). Data were collected via telephone (n = 267) and face-to-face interviews (n = 60) including the Comprehensive Assessment of Symptoms and History interview, Positive And Negative Syndrome Scale and the Psychotic Symptom Rating Scale. Results: The point prevalence of delusions was 26%, with a median strong delusion conviction. For the group as a whole, the presence and severity of both hallucinations and delusions was found to be stable at follow-up. Participants with persistent hallucinations experienced more comorbid psychiatric disorders, and they differed from those with intermittent or sporadic hallucinations with their hallucinations being characterized by a higher frequency, causing a higher intensity of distress and more disruption in daytime or social activities. Conclusions: Delusions in patients with BPD occur frequently and cause distress. Contrary to tenacious beliefs, hallucinations and delusions in participants with BPD are often present in an intermittent or persistent pattern. Persistent hallucinations can be severe, causing disruption of life. Overall, we advise to refrain from terms such as “pseudo”, or assume transience when encountering psychotic phenomena in patients with BPD, but rather to carefully assess these experiences and initiate a tailor-made treatment plan.