Borderline personality and late, missed, and mis-diagnosis in female autism: A review of the literature

Autism spectrum disorder (ASD) without intellectual disability is diagnosed later and with greater difficulty in females relative to males. For autistic girls and women, the journey to an autism diagnosis may include one or more misdiagnoses. Misdiagnosis with borderline personality disorder (BPD) or borderline traits may be particularly common, and characteristics often observed in autistic girls and women may contribute specifically to a risk of misdiagnosis with BPD. This review draws from a burgeoning literature on ASD in girls and women to provide a detailed discussion of differential diagnosis of BPD and ASD in cisgender females, with a focus on phenotypic features and/or their presentation that are common in autistic females and that may be particularly prone to miscategorization as BPD. Distinctions between ASD and BPD are identified, emphasizing the need for scrutiny of an individual’s clinical presentation to tease apart potentially subtle yet superficial differences between the ASD and BPD phenotypes, which belie more obvious, deeper differences in diagnostic meanings. We highlight instances in which similar symptom expression may be driven by differing underlying factors. Implications for the distinction of ASD and BPD/borderline traits in informing appropriate therapeutic intervention are discussed.