Repeated head injury increases risk of dementia

09 March 2021

Researchers in the US have found that head injury is linked to an increased risk of dementia. They also found the more head injuries sustained, the more likely someone is to develop the condition and females are at greatest risk. The journal, Alzheimer’s & Dementia reports the results today (Tuesday 9 January).

What did the researchers look for?

They asked volunteers without dementia to self-report whether they had sustained a brain injury. The brain injuries focussed on injuries involving a loss of consciousness.

They followed the volunteers over 25 years to see who developed dementia.

What did they find?

They found that head injury was linked with an increased risk of dementia. This link was stronger in females than in males.

Our expert view:

Dr Susan Kohlhaas, Head of Research at Alzheimer’s Research UK, said:
“From traffic accidents to collision sports, millions of people around the world experience head injuries every year. These injuries can result in immediate damage to the brain, but this research is more evidence that they could also have significant effects in the longer-term.

“In this study, the findings suggest the more brain injuries sustained, the more likely someone may be to develop dementia. The findings also strengthen evidence that dementia risk is greatest for females who sustain head injuries. While self-reporting is a reliable way of assessing head injuries, mild injuries were not the focus of the study and may have been missed.

“Only through more research will we begin to fully understand the link between head trauma and dementia. Importantly, research like this will allow us to help bring about clear interventions and policies to reduce the risk of dementia.

“While no-one sets out to sustain a head injury, there are things we can do to reduce the risk of dementia throughout our lives, even after brain injury. That’s why Alzheimer’s Research UK has launched the thinkbrainhealth.org.uk campaign to help people become more aware of the things they can do to protect their brain health.”