Cognitive and neurobehavioral phenotypes of post 9/11 veterans with epilepsy and mild traumatic brain injury

Traumatic brain injury (TBI) and epilepsy are significant health concerns among the veteran population, but the links between mild TBI and cognitive and behavioral changes in epilepsy have been little explored. This study leveraged natural language processing of medical records and chart review to assess the prevalence and patterns of cognitive and behavioral symptoms in post-9/11 veterans with epilepsy, with and without history of mild TBI. The study objective was to identify distinct neurobehavioral phenotypes, and then explore their socio-demographic factors, comorbidities, and phenotypes.

We conducted a detailed chart review using NLP to extract cognitive dysfunction indicators that were categorized into seven Research Domain Criteria domains. Employing Uniform Manifold Approximation and Projection for clustering and dimensionality reduction.

By clustering individuals on behavioral and cognitive concepts in medical notes, this study extends beyond traditional diagnostic classifications, revealing a cognitive and behavioral phenotype of veterans. Veterans with post traumatic epilepsy often demonstrate significant cognitive risk profiles associated with RDoC domains, particularly in domains related to cognitive function and arousal/regulatory systems. Both veterans with TBI before Epilepsy post traumatic epilepsy and those with epilepsy preceding TBI displayed greater cognitive and behavioral burden compared to veteran with TBI only. Notably, epilepsy preceding TBI were found more often clustering in high behavioral risk profiles. This group with epilepsy preceding TBI was associated with, including dysfunction in the RDoC domains related to negative valence systems (44.4%), arousal/regulatory systems (37.0%), and interpersonal trauma.

These findings highlight the complex interplay between TBI and Epilepsy in shaping long term cognitive/behavioral challenges and point to the need for targeted clinical management, personalized treatment approaches, and refined therapeutic strategies to maximize the quality of life for affected veterans.