Identifying autism in women diagnosed with borderline personality disorder: Clinician and lived experience perspectives.

This qualitative study involving clinicians and women with a borderline personality disorder (BPD) diagnosis reveals that systemic barriers, diagnostic biases, and a lack of clinician knowledge regarding autism's diverse presentations frequently lead to misdiagnosis, highlighting the urgent need for improved differential diagnosis training, collaborative care pathways, and more cautious assessment practices to better identify undiagnosed autism in this population.

The Gist

The Big Picture: A Case of Mistaken Identity

Imagine you walk into a mechanic's shop because your car is making a strange noise and shaking violently. The mechanic looks at the shaking, hears the noise, and immediately says, "Ah, you have a broken engine." They hand you a manual for fixing engines and tell you to follow those steps.

But what if the problem isn't the engine at all? What if the car is actually shaking because the tires are the wrong size for the road, and the noise is because the air conditioning is stuck on full blast? The mechanic is treating the "engine" (Borderline Personality Disorder, or BPD), but the real issue is the "tires and AC" (Autism).

This study is about women and people assigned female at birth who were told they had a "broken engine" (BPD), only to realize later that their car was actually built differently (Autism). The researchers wanted to know: Why did the mechanics (clinicians) keep fixing the engine when the tires were the real problem?

Who Did the Researchers Talk To?

They didn't just look at medical charts. They had deep conversations with two groups:

1. 15 "Drivers" (Lived Experience): Women who had been diagnosed with BPD but now think (or know) they are actually autistic.
2. 15 "Mechanics" (Clinicians): Mental health professionals who work with both BPD and autism.

The Four Main Problems They Found

1. The "Crisis Label" (The Emergency Room Mistake)

The Analogy: Imagine you are in a panic attack in the ER. The doctor sees you shaking and crying and immediately writes "Heart Attack" on your chart because that's the most dangerous thing they see right now. They don't have time to check your blood pressure history or your diet.

The Finding: The study found that BPD is often diagnosed very quickly during a mental health crisis (like a suicide attempt or self-harm). Because the patient is in a state of high distress, clinicians focus on managing the immediate danger. They slap on the "BPD" label to get the patient into therapy (like DBT) quickly.

• The Result: By the time the patient is calm enough to look at their whole life, the "BPD" label is already stuck on them like superglue. It becomes hard to peel off, even if it doesn't fit.

2. The "Filter" (Seeing Only What You Expect)

The Analogy: If you put on red-tinted glasses, everything looks red. If you put on "BPD glasses," every behavior looks like a symptom of BPD.

The Finding: Once a patient has a BPD diagnosis, clinicians often stop looking for other explanations.

• Example: If an autistic person is rigid about their routine, the "BPD glasses" might see this as "controlling behavior" or "instability."
• Example: If an autistic person is quiet and doesn't make eye contact, the "BPD glasses" might see this as "manipulative" or "fear of abandonment."
• The Barrier: Clinicians admitted they are sometimes afraid to question a colleague's diagnosis because it feels like challenging the team. Patients also feel afraid to speak up because they think, "If I say I'm not BPD, they'll think I'm in denial or crazy."

3. The "Silo" (Separate Rooms for Separate Problems)

The Analogy: Imagine a hospital where the "Heart Department" and the "Neurology Department" are in completely different buildings with no doors between them. If you have a heart condition that is actually caused by a nerve issue, the Heart doctors won't look at the Neurology files.

The Finding: The mental health system is divided. There are "Personality Disorder Services" and "Autism Services." They rarely talk to each other.

• To get into the "Personality Disorder" room, you often must have a BPD diagnosis.
• To get into the "Autism" room, you often need to prove you don't have a personality disorder.
• This forces patients to fit into a box that doesn't fit them, just to get help.

4. The "Cost of the Mask" (Hiding the Real You)

The Analogy: Imagine you are wearing a heavy, hot winter coat in the middle of summer. You are sweating and exhausted, but you keep the coat on because everyone else is wearing one. The doctor sees you sweating and says, "You have a fever!" They don't realize you are just wearing the wrong coat.

The Finding: Many autistic women are experts at "masking"—hiding their autistic traits to fit in with neurotypical people.

• They learn to force eye contact, mimic social cues, and suppress their sensory needs.
• When they finally crash (burnout), it looks like a BPD meltdown.
• Clinicians often miss the autism because they only see the "sweating" (the crash) and not the "coat" (the years of masking). They also often rely on outdated ideas that autism only looks like a stereotypical boy who loves trains, missing the quiet, internalized autism of women.

What Happens When the Mistake is Fixed?

The study found that when these women finally realized, "Wait, I'm not broken; I'm just autistic," it was like taking off that heavy winter coat.

• Relief: They stopped blaming themselves for "not trying hard enough."
• Understanding: They realized their sensory issues (like hating loud noises) weren't "emotional instability," but a physical reaction.
• Better Care: They could ask for the right kind of help (like a quiet room) instead of being told to "manage their emotions" in a way that didn't work for them.

The Catch: A New Problem?

However, there is a twist. Some participants said that getting an autism diagnosis alongside a BPD diagnosis made things worse.

• The "Too Complex" Trap: Some services said, "You have both? That's too complicated. We can't help you."
• The Barrier: Some clinicians were afraid to diagnose autism because they thought it would disqualify the patient from the therapy they needed (like DBT).

The Bottom Line

The researchers concluded that to fix this, we need to:

1. Slow Down: Don't diagnose BPD in the middle of a crisis without looking at the whole picture.
2. Listen: Take patients seriously when they say, "I don't think this diagnosis fits me."
3. Connect the Rooms: Make sure autism and personality disorder services talk to each other.
4. Update the Manuals: Clinicians need to learn what autism looks like in women (who often mask their symptoms) so they don't mistake it for a personality disorder.

Important Note: The paper explicitly states that this is a preprint and has not been peer-reviewed yet. The authors warn that these findings should not be used to guide clinical practice immediately, as they are still being verified.

Technical Summary

1. Problem Statement

There is a growing recognition that autistic adults, particularly women and people assigned female at birth (AFAB), are frequently misdiagnosed with Borderline Personality Disorder (BPD). This misdiagnosis leads to significant harm, including inappropriate treatment pathways, iatrogenic effects from therapies not suited to autistic needs, and a lack of self-understanding.

While previous qualitative research has explored the experiences of autistic adults previously diagnosed with BPD, critical gaps remain:

• Existing studies have not focused specifically on the barriers and facilitators to this diagnostic journey.
• They have largely excluded the perspectives of clinicians, creating a one-sided view.
• They have not included individuals who are unsure of their autistic status (self-identified or suspected).
• There is a lack of understanding regarding how systemic factors (e.g., service silos, crisis-driven assessments) contribute to the over-diagnosis of BPD and the under-diagnosis of autism in this demographic.

2. Methodology

The study employed a qualitative design utilizing in-depth semi-structured interviews and reflexive thematic analysis grounded in a critical realist ontology and relativist epistemology.

• Participants:
  • Lived Experience Group ($N=15$): Women/AFAB individuals aged 18–65 with a current or historical BPD diagnosis who identified as definitely or possibly autistic. Participants were recruited from NHS services and social media across the UK.
  • Clinician Group ($N=15$): Mental health professionals (psychiatrists, psychologists, nurses, peer support workers) working with autism and/or personality disorders in the UK.
• Data Collection:
  • Interviews were conducted via telephone, video conferencing, or in-person (one case).
  • Lived Experience prompts: Focused on the journey to realizing they might be autistic, their agreement with the BPD diagnosis, and barriers/facilitators to recognition.
  • Clinician prompts: Focused on differentiating autism and BPD in practice, barriers to assessment, and systemic issues.
• Analysis:
  • Data was analyzed using Braun and Clarke's reflexive thematic analysis steps (familiarization, coding, theme generation, refinement).
  • The lead interviewer/analyst (JP) has lived experience of both BPD and late-diagnosed autism, necessitating rigorous reflexivity to distinguish participant accounts from researcher assumptions.
  • Analysis was reviewed by a co-analyst and advisory panels (both clinician and lived experience) to ensure grounding in participant data.

3. Key Contributions

This study is the first to integrate clinician and lived experience perspectives simultaneously regarding the misdiagnosis of autism as BPD. Its primary contributions include:

• Systemic Critique: It highlights how service structures (e.g., the requirement of a BPD label to access specific therapies like DBT) incentivize misdiagnosis.
• Differentiation Framework: It provides a nuanced comparison of how similar behaviors (e.g., emotional dysregulation, relationship instability) manifest differently in autism (often sensory/routine-driven) versus BPD (often relational/trauma-driven).
• Barriers to Diagnosis: It identifies specific barriers such as the "sticky label" effect of BPD, the lack of developmental history access, and clinician reliance on outdated stereotypes of autism (e.g., intellectual disability).
• Epistemic Justice: It argues for the validity of patients questioning their diagnoses and the need to treat patients as experts in their own experiences.

4. Results

The analysis identified four main themes:

Theme 1: Borderline Personality Disorder: A "Sticky Label" Based on Spurious Evidence

• Crisis-Driven Diagnosis: BPD diagnoses are often made rapidly during mental health crises (e.g., self-harm, suicide attempts) with minimal assessment, prioritizing risk management over differential diagnosis.
• Systemic Incentives: Clinicians reported feeling pressured to assign a BPD diagnosis to unlock access to psychological therapies (e.g., DBT), deprioritizing autism screening.
• The "Sticky Label": Once a BPD diagnosis is assigned, it creates a confirmation bias where subsequent behaviors are interpreted through the BPD lens. Patients questioning this diagnosis are often pathologized as being "in denial" or exhibiting BPD traits.
• Demographic Factors: Traits such as bisexuality, tattoos, trauma history, or simply not fitting other categories were cited as contributing factors to BPD misdiagnosis.

Theme 2: Seeing Beyond BPD to Autism

• Self-Discovery: Many participants discovered their autism through self-education (social media, literature) rather than clinical observation, often finding the autistic framework fit their life history better than BPD.
• Clinical Differentiation:
  • Emotional Dysregulation: In autism, this is often triggered by sensory overload, routine changes, or fatigue. In BPD, it is more frequently linked to interpersonal rejection or abandonment.
  • Social Interaction: Autistic social difficulties often stem from a lack of understanding of implicit cues or literal interpretation. BPD social difficulties are characterized by hypersensitivity to cues and fear of abandonment.
  • Misattribution: Autistic "special interests" are often mislabeled as BPD "idealization"; autistic rigidity is mislabeled as BPD "obsessiveness"; and autistic shutdowns are mislabeled as BPD "dissociation."
• Masking: Participants noted that years of "masking" (camouflaging autistic traits) can lead to the development of secondary BPD-like traits (e.g., emotional exhaustion, rejection sensitivity), complicating the clinical picture.

Theme 3: Overcoming Barriers to Autism Assessment

• Stereotypes: Clinicians often lack awareness of how autism presents in women/AFAB (e.g., internalized, high-masking presentations).
• Assessment Limitations: Reliance on observational tools like the ADOS is problematic for high-masking individuals who can maintain a "mask" for short periods. Participants suggested longer assessments and self-report measures are more effective.
• Developmental History: A major barrier is the requirement for childhood informants. For adults with deceased parents, estranged families, or traumatic childhoods, obtaining this history is impossible, leading to diagnostic exclusion.
• Service Silos: Autism and personality disorder services are often separate, preventing a holistic view of the patient.

Theme 4: Consequences of Recognizing Autism

• Positive Outcomes: Recognizing autism led to improved self-understanding, self-compassion, and better quality of life. It allowed individuals to reframe their struggles as neurodivergent needs rather than character flaws.
• Negative Outcomes (The "Two-Way Exclusion"): Some participants reported that receiving an autism diagnosis (especially with a co-occurring BPD diagnosis) made them "ineligible" for services, as they fell into a gap between autism and personality disorder pathways.
• Therapeutic Mismatch: Standard BPD therapies (e.g., MBT, DBT) were sometimes reported as harmful or ineffective for autistic individuals if not adapted, as they may fail to account for sensory needs or literal thinking styles.

5. Significance and Implications

• Clinical Practice: Clinicians must be trained to recognize internalized autism presentations in women/AFAB and to differentiate between autism-driven and BPD-driven emotional dysregulation. Assessments should avoid rapid diagnosis during crises.
• Service Reform: There is an urgent need to break down silos between autism and personality disorder services. Transdiagnostic access to therapies (allowing access based on need rather than specific diagnosis) is recommended.
• Diagnostic Process: Guidelines regarding the necessity of childhood informants need revision to accommodate adults with disrupted histories. Assessment methods should move beyond observation to include self-report and longer observation periods to detect masking.
• Epistemic Justice: The study advocates for taking patients' self-identification and questioning of diagnoses seriously, rather than pathologizing their skepticism as a symptom of their existing diagnosis.
• Future Research: Further investigation is needed into adapting evidence-based psychological interventions for autistic individuals and exploring the validity of the BPD construct in the context of undiagnosed autism and complex trauma.

Limitations: The study sample was predominantly White British and highly educated, limiting generalizability to ethnically diverse groups. The findings may also reflect a current societal discourse skeptical of BPD and embracing neurodiversity, potentially influencing participant recruitment and responses.