TRAUMATIC brain injury (TBI), particularly in later life, is associated with a significantly increased risk of long-term mortality driven largely by dementia-related deaths, according to new data from the Framingham Heart Study.
TBI Incidence Rises with Age and Falls
Using more than seven decades of follow-up data, researchers examined how often TBI occurs across the lifespan and whether it contributes to long-term mortality. The study found that TBI most commonly occurs in older adults, with falls identified as the leading cause. Across the original and offspring cohorts, incidence rates ranged from 7.02 to 9.11 TBI events per 1000 person-years. The mean age at first TBI was in the early to mid-70s, underscoring the vulnerability of older adults to head injury. Transportation-related injuries were more common earlier in life, but falls dominated in later decades.
Dementia Drives Increased Mortality Risk
Participants who experienced TBI had a higher risk of all-cause mortality compared with matched controls, with risk increasing alongside injury severity. Mild TBI was associated with a modest increase in mortality, while moderate to severe TBI nearly doubled the risk.
Importantly, this association was largely explained by dementia-related deaths. Mild TBI increased dementia-related mortality risk by 60%, while moderate to severe TBI was associated with more than a threefold increase. No significant association was observed between TBI and non-dementia-related mortality, highlighting dementia as the primary pathway linking brain injury to long-term death.
Dose Response Highlights Cumulative Harm
The analysis also demonstrated a dose-response relationship. Individuals who sustained multiple TBIs or more severe injuries faced progressively higher risks of dementia-related mortality. These findings support the view that TBI should not be considered a one-time event but rather a condition with cumulative neurological consequences.
The long follow-up period allowed researchers to observe how injury-related brain changes may contribute to neurodegeneration decades later, strengthening evidence that TBI accelerates or exacerbates dementia-related processes.
Prevention Focus Shifts to Fall Reduction
Given that most TBIs in this cohort occurred in late life and were caused by falls, the findings have clear public health implications. Strategies aimed at fall prevention in older adults may reduce both TBI incidence and downstream dementia-related mortality.
As populations age, preventing falls may represent one of the most effective interventions to reduce the long-term cognitive and survival consequences associated with traumatic brain injury.
Reference
Burton R et al. Traumatic brain injury and all-cause and dementia-related mortality in the framingham heart study. JAMA Netw Open. 2026;9(1):e2555138.
