Prevalence & Comorbidity: Trauma, Personality Disorders & Eating Disorders in Australia

Prevalence in Australia: Around 5.7% of adults experience PTSD in any 12 months (ABS, 2022).
Gender differences: More common in women, often linked to interpersonal trauma.
With Eating Disorders: Co-occurring up to 26% of people with EDs also meet criteria for PTSD. Symptoms like hypervigilance, emotional numbing, and intrusive memories can reinforce disordered eating behaviours as coping strategies.

Prevalence: Harder to capture with national data because it is not a standalone DSM-5 diagnosis, but research suggests 10–20% of people exposed to chronic trauma (e.g., childhood abuse, neglect) develop C-PTSD symptoms.
Features: Intense emotional dysregulation, shame, identity disturbance, and relational difficulties.
With Eating Disorders: Complex trauma strongly overlaps with restrictive and binge–purge patterns. Disordered eating can function as a way to regulate emotions, dissociate, or regain control. No stats have been studied to date.

Prevalence: Adjustment disorders are one of the most common diagnoses in outpatient and hospital mental health settings, but estimates range between 2–8% of the Australian population.
Features: Emotional or behavioural symptoms in response to a major life stressor (e.g., loss, illness, transitions).
With Eating Disorders: Stressful transitions can trigger disordered eating or body image distress. Adjustment disorders are often underdiagnosed, but they may represent a “gateway” to more severe disorders if support is not accessed.

Prevalence: Around 6–10% of the Australian population meets DSM-5 criteria for a personality disorder.
With Eating Disorders: Comorbidity rates vary but are estimated at up to 30–50% in clinical ED samples. Personality styles can impact how someone experiences their ED, engages with treatment, and relates to others.

Subtypes

Borderline Personality Disorder (BPD): Approximately 1–2% of Australians. Strong links with binge–purge EDs and self-harm. Emotional dysregulation is a core feature.
Obsessive–Compulsive Personality Disorder (OCPD): Approximately 2–4%. Frequently co-occurs with restrictive EDs due to rigidity, perfectionism, and control.
Narcissistic Personality Disorder (NPD): Less than 1% prevalence. May contribute to vulnerability through fragile self-esteem and body image concerns.
Avoidant Personality Disorder (AvPD): Approximately 2%. Associated with social anxiety, body shame, and EDs.
Antisocial Personality Disorder (ASPD): Approximately 1–3%. Less common in EDs, but may appear in certain presentations with impulsivity.
Dependent Personality Disorder (DPD): Approximately 0.5–1%. Overlaps with EDs where self-worth is externally defined, leading to reliance on others for validation.

Holistic treatment: Many people with eating disorders live with co-occurring trauma histories or personality vulnerabilities. Ignoring these factors risks incomplete care.
Reducing stigma: Trauma and PDs are often misunderstood. Highlighting prevalence helps normalise these conditions and reminds clients they are not alone.
Therapy implications: Recovery often requires integrating multiple approaches (DBT, IFS, Schema Therapy) to address emotional regulation, interpersonal patterns, and identity.
Empowerment: Recognising the link between trauma, personality, and eating behaviours validates lived experiences and fosters more compassionate, tailored recovery pathways.

Comorbidity of Trauma and PDs with Eating Disorders