Scientists have studied female US military veterans and found that traumatic brain injury (TBI), depression or post-traumatic stress disorder (PTSD) are linked to an increased risk of dementia. The findings are published today (Wednesday 12 December) in the scientific journal, Neurology.
The researchers looked at data from 109,140 US female military veterans over the age of 55 years who did not have a diagnosis of dementia. Researchers then monitored the participants for an average of 4 years to see if they developed the condition.
The research team also looked to see if the study participants had a traumatic brain injury (TBI), depression, PTSD or more than one of these conditions.
During the study, scientists took into account a number of factors, including the number of visits people made to healthcare services, and also imposed a two-year time limit between exposure to a risk factor and a dementia diagnosis.
They found that overall 4% of all the women in the study developed dementia, however people with traumatic brain injury, depression and PTSD were between 50% and 80% more likely to be diagnosed with the condition. Additionally, women with at least two of the risk factors had more than a two-fold risk of developing dementia.
Dr Carol Routledge, Director of Research at Alzheimer’s Research UK, said:
“While head injury, depression and PTSD are likely to be particularly common in military veterans, they can affect people in all walks of life. This study provides a valuable opportunity to assess how these factors are related to dementia risk in research that involves a large group of women who were monitored over a long period of time.
“Although this research still cannot definitively tell us if these factors cause an increased dementia risk, it adds to a growing body of evidence linking mental health as well as physical brain injury to the development of the condition. As the study only looked at associations between dementia diagnosis and these potential risk factors, it doesn’t offer any insight into the mechanisms underpinning these relationships.
“Alzheimer’s Research UK is funding research into how brain injury is related to the risk of dementia and is supporting scientists who are exploring strategies that could help to keep our brains healthy as we age.
“The best current evidence suggests a relationship between a lower dementia risk and healthy lifestyle choices such as not smoking, only drinking within recommended limits, controlling blood pressure and cholesterol, staying mentally and physically active and eating a healthy, balanced diet.”