Background and objectives:
In Australia, mental health and acquired brain injury (ABI) services are distinct and funded independently, preventing the development of effective methods to identify psychological support needs in this group. This is despite up to 80% of adults with ABI experiencing comorbid anxiety or depression in the 5 years following injury. This study aims to identify mental health conditions commonly comorbid in individuals with ABI, to allow an early-intervention mental health screening tool to be developed.

Method:
Retrospective cohort study of 1,011 adults with ABI admitted to neurorehabilitation or disability support services in Western Australia (WA), 1991-2020. Mental health symptomatology and diagnoses were identified using electronic medical records, and hospital and emergency department data from the WA Data Linkage System. Mental health presentations were examined across 15 diagnostic categories (e.g. substance use disorders, anxiety disorders) and 3 non-diagnostic categories (e.g. self-harm) using the International Classification of Diseases 9th and 10th edition and WA Data Linkage System codes.

Results:
Preliminary results indicate that mental health comorbidities are common, with 56.1% presenting with a mental health condition within 12 months of their admission to services. This indicates the presence of significant mental health burden, with difficulties likely persisting beyond admission to post-acute services.

Conclusion:
Mental health comorbidities are common in individuals with ABI. Identification of these conditions will allow appropriate management and intervention. Cluster analysis will be conducted to identify commonly co-occurring mental health conditions. Development of key diagnostic clusters will inform a new mental health screening tool, permitting early identification of mental health complexity in ABI, and provide data to inform effective interventions.