The experiences of autistic adults who were previously diagnosed with borderline or emotionally unstable personality disorder: A phenomenological study
Authors: Tamilson Bruce , Eccles Jessica A , Shaw Sebastian C K 
Published: September 2024

An increasing number of studies are investigating the links between autism and borderline personality disorder. Studies report overlapping differences and the challenges in differentiating between these two diagnostic labels. In practice, there are many people, especially autistic women, who feel that they were misdiagnosed with borderline personality disorder. This study aimed to explore the experiences of autistic adults who were previously diagnosed with borderline personality disorder. This is an interpretive phenomenological study. Data were collected using one-to-one, semi-structured interviews. Interview audio-recordings were transcribed and analysed using an interpretive phenomenological analysis. Ten people participated. All recalled autistic differences since childhood that went unnoticed. In most cases, borderline personality disorder was felt to have been a misdiagnosis. This misdiagnosis carried stigma, introduced diagnostic overshadowing and led to harmful experiences for our participants. While they did not identify with the diagnosis, they felt powerless to challenge it. In contrast, receiving an autism diagnosis was ‘life changing’. While this did not solve everything for them, it was deeply validating. It also allowed them to be their true authentic selves, shifting the focus away from ‘treatment’ and changing who they are to suit others, towards acceptance of their differences and neurotype. This significantly improved their mental health. Lay Abstract Autistic people face many barriers to receiving an autism diagnosis. Often, they may be misdiagnosed with borderline personality disorder instead. For our study, we interviewed 10 autistic adults who had previously been diagnosed with borderline personality disorder. This helped us to better understand their experiences. They explained how borderline personality disorder is quite stigmatised and may suggest that people are to blame for their differences in behaviour. They found the treatments they had to try for borderline personality disorder to be harmful. For example, these treatments promoted ‘masking’. Previous research showed that masking can be harmful for autistic people, linking it to risk of suicide. This diagnosis also led to healthcare professionals neglecting them and discounting their beliefs. Once they were diagnosed with borderline personality disorder, it was hard to access an autism assessment. When they did receive their autism diagnoses, this was much more positive. This diagnosis was validating. It also improved their mental health, as they were no longer expected to mask – their differences were now accepted. They still felt that autism was stigmatised in society. However, this was very different to the stigma around borderline personality disorder. They felt autism stigma was more about their competence as people, whereas borderline personality disorder stigma was about how they were broken and might be harmful to others. This study is important because it allows their stories to be heard by researchers and healthcare professionals alike. Adding their voices helps to humanise them, promoting positive change in mental health services. More research is now needed.