Characterizing the Prevalence of Dementia Risk Factors in Moderate-to-Severe Traumatic Brain Injury

In the current study, we aimed to determine whether adults with a history of moderate-to-severe traumatic brain injury (TBI) carry a greater burden of modifiable dementia risk factors than demographically matched healthy controls. This was a cross-sectional observational study. Participants were recruited from a pre-existing database of individuals who had previously undergone inpatient rehabilitation at a private hospital in Melbourne, Australia. The study included 106 individuals with a history of moderate-to-severe TBI and 106 demographically matched healthy controls with no TBI history. Participants in the TBI group were at least 1-year post-injury. The groups were matched on age, sex, and years of education. Self-report measures were used to assess a range of modifiable dementia risk factors, including sensory (hearing), mental health (depressive symptoms), lifestyle (social engagement, physical activity, smoking, sleep quality), and cardiometabolic factors. A 14-item composite score was calculated to index the overall modifiable-risk burden. Compared to controls, the TBI group reported significantly poorer hearing, greater depressive symptoms, lower social engagement, higher lifetime smoking prevalence, and poorer sleep quality. However, vascular and metabolic health profiles were similar between groups. The overall composite risk score did not significantly differ between the TBI group and the control group. Individuals with a history of moderate-to-severe TBI demonstrate a distinct profile of modifiable dementia risks rather than a globally elevated risk burden. These findings suggest a need for targeted post-injury surveillance and interventions that focus on auditory health, mental well-being, social participation, smoking cessation, and sleep to help mitigate future dementia risk.