The study of Traumatic brain injury and dementia

Abstract

The relationship between traumatic brain injury (TBI) and the risk of dementia remains controversial This study was designed to estimate and compare the risk of dementia in TBI and non-TBI individuals after TBI This study was a retrospective cohort study Data were obtained from the Taiwan’s National Health Insurance Research Database (NHIRD) Disease was defined on the basis of at least two NHI ambulatory claim records or one inpatient record Cases were categorised as per the diagnosis codes assigned by the International Classification of Diseases 9th Revision Clinical Modification (ICD-9-CM) Data were analysed by Cox proportional hazard regression The main finding of our study were that TBI was independently associated with a 1 68 times greater risk of dementia after adjusting for sociodemographic characteristics and selected comorbidities Frontotemporal dementia (FTD) was more likely to occur in the TBI group Furthermore we used a rat model of TBI to show that increased TDP-43 proteolysis following TBI produces FTD-like impairments including abnormal limb-clasping and impaired performances in the Morris water maze The findings of this study suggest an increased risk of dementia among individuals with TBI especially in FTD NHIRD is a suitable tool to study TBI and dementia Rats developed behavioral impairment similar to those in patients with FTD after TBI Further the behavioral impairments were likely associated with TDP-43 short fragment mislocalization and accumulation Recently a chronic inflammatory response which is an ongoing perhaps lifelong process was considered as a mechanism possibly linking TBI to dementia Several studies have demonstrated that TBI is associated with inflammatory immune alterations including increased levels of cytokines and increased microglial activation Although the evidence suggests that TBI is a risk factor for dementia further research in this area is necessary to answer these questions and examine whether proper management of TBI is effective in reducing the incidence of dementia

Date of Award	2015 Apr 22
Original language	English
Supervisor	Kuen-Jer Tsai (Supervisor)