By Stephen Spotswood

WASHINGTON--The news that patients with TBI could have a higher risk of dementia later in life has reverberated far outside the veteran patient community where the research was conducted. With TBI accounting for 22% of casualties in Iraq and Afghanistan and 59% of troops exposed to blasts, veterans and service organizations are concerned that the coming decades could see a virtual epidemic of dementia in these servicemembers.

Lt. Col. (Dr.) Margaret Swanberg tests a solder for signs of concussion in 2008. She was the only Army neurologist deployed to Iraq at the time. Photo courtesy of the Army.

VA clinical leaders stress caution going forward, however, noting that the highly-publicized research is from one unpublished study. The full link between TBI and dementia remains unknown, they maintain.

Last summer, researchers at the San Francisco VA Medical Center (SFVAMC) presented findings at the 2011 Alzheimer’s Association International Conference in France showing that patients diagnosed with TBI had more than twice the risk of developing dementia within seven years of diagnosis.

Their findings came from a study of 280,000 older veterans at the SFVAMC, where 15% of veterans who received a diagnosis of TBI developed dementia compared with 7% of those without a diagnosis.

These findings have yet to be published.

“The reports that are emerging about potential links between TBI and dementia are very important to us, but it’s an area that requires more research,” explained Susan Cooley, PhD, VA’s chief of geriatrics. “It’s especially important from the perspective of those of us having to plan ahead for dementia care in VA.”

 Suggestions that brain injury could lead to dementia have been in the medical literature since the 1970s, explained David Cifu, MD, VA’s national director of physical medicine and rehabilitation services. “It isn’t a stretch to the imagination that having one serious brain injury or a series of smaller ones would lead to a degenerative brain condition over time, but there’s a huge leap from what seems to make sense and the science that there is a specific association.”

According to Cifu, the available research into the link shows an association between TBI and dementia about 50% of the time.

“We’re only seeing associations but no proven correlations,” he said.

Dementia incorporates complex processes, with multiple factors that promote it and an equal number that prevent it from developing, he pointed out. The currently available research has far too many variables to prove a definitive link.