In Veterans, Even a Mild Case of Traumatic Brain Injury Is Linked to an Increased Risk of Dementia

A study published in JAMA Neurology indicates that mild traumatic brain injury (TBI) can raise the risk of developing dementia in veterans, reports the Los Angeles Times . The researchers analyzed the medical records of more than 350,000 U.S. soldiers serving in wars in Iraq and Afghanistan, and found those who experienced at least one mild TBI were more than twice as likely as their uninjured counterparts to develop dementia after retirement. The team sifted through government databases to identify everyone treated by the Veterans Health Administration (VHA) who was diagnosed with any kind of TBI between 2001 and 2014; 178,779 individuals were identified. For 10 percent of these veterans, the most severe instance of TBI was a mild TBI without any loss of consciousness. Another 13 percent had a mild TBI that made them lose consciousness for no more than half an hour, while almost 31 percent were diagnosed with mild TBI, but their medical records did not note whether they had lost consciousness as a result. The remaining 46 percent had a TBI rated moderate or severe. These veterans were matched with another 178,779 controls without a TBI; 2.6 percent of them were eventually diagnosed with dementia, as were 6.1 percent of veterans with a history of TBI. The odds of developing dementia were 2.51 times greater for veterans with mild TBI who lost consciousness for a short period of time, and 3.19 times greater for veterans with mild TBI whose records did not indicate whether they had lost consciousness or not. Veterans with moderate to severe TBI were almost four times more likely than their uninjured peers to develop dementia during the study period.