Older individuals who have experienced traumatic brain injury (TBI) could be as much as 60 per cent more likely to develop dementia.
Nearly 190,000 people were studied, with an average age of 68 when the trial commenced. None of them had any form of the degenerative disease and visited the San Francisco Veterans Affairs Medical Center at least once at the beginning of the research and then seven years later.
In total, 1,229 of the individuals had TBI. It transpired 16 per cent of these developed cognitive decline when the follow-up period took place, in comparison to 10 per cent of the individuals that didn't.
Furthermore, older people with TBI were diagnosed with the degenerative condition two years earlier than those without it (78.5 compared to 80.7).
"This study convincingly shows that mild trauma has a role in increasing the risk of dementia," author Dr Deborah Barnes from the University of California, San Francisco and the San Francisco Veterans Affairs Medical Center.
The full findings can be viewed online in the journal Neurology.
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