Traumatic Brain Injury and Early Onset Dementia in Post 9-11 Veterans

Objectives To assess traumatic brain injury (TBI)-related risks factors for early-onset dementia (EOD). Background Younger Post-9/11 Veterans may be at elevated risk for EOD due to high rates of TBI in early/mid adulthood. Few studies have explored the longitudinal relationship between traumatic brain injury (TBI) and the emergence of EOD subtypes. Methods This matched case-control study used data from the Veterans Health Administration (VHA) to identify Veterans with EOD. To address the low positive predictive value (PPV = 0.27) of dementia algorithms in VHA records, primary outcomes were Alzheimer's disease (AD) and frontotemporal dementia (FTD). Logistic regression identified conditions associated with dementia subtypes. Results The EOD cohort included Veterans with AD (n = 689) and FTD (n = 284). There were no significant demographic differences between the EOD cohort and their matched controls. After adjustment, EOD was significantly associated with history of TBI (OR: 3.05, 2.42-3.83), epilepsy (OR: 4.8, 3.3-6.97), other neurological conditions (OR: 2.0, 1.35-2.97), depression (OR: 1.35, 1.12-1.63) and cardiac disease (OR: 1.36, 1.1-1.67). Conclusion Post-9/11 Veterans have higher odds of EOD following TBI. A sensitivity analysis across TBI severity confirmed this trend, indicating that the odds for both AD and FTD increased after more severe TBIs.