TBI appears to be related to both increased risk and earlier onset of mild cognitive impairment (MCI), UT Southwestern Medical Center researchers report. Researchers discovered those who had experienced a TBI with loss of consciousness for more than five minutes were at greater risk of being diagnosed with MCI and showed signs of that impairment 2.3 years earlier on average than those with no TBI history. The study analyzed cases of 3,187 people diagnosed with mild cognitive impairment versus a normal-cognition group of 3,244 in a large, multicenter national database. The researchers found several important variables associated with a higher risk for MCI: TBI with loss of consciousness for greater than five minutes, certain genetic risk factors, and a history of depression. However, these MCI risk factors need closer examination, researchers said. The study was published recently in the Journal of Alzheimer’s Disease.
The data came from patient information documented in the National Alzheimer’s Coordinating Center database, which is pooled from 29 National Institute of Aging-funded Alzheimer’s disease centers in the U.S. The group studied included those age 50 or older who had initial and follow-up visits completed between September 2005 and December 2013. “TBI is hypothesized to activate a neurodegenerative process that may interact with age and other factors over time,” Dr. Cullum said. “This study shows a correlation between TBI and MCI, but more research remains to be done to explore this apparent link. Factors such as neuroinflammation and buildup in the brain of proteins such as tau or amyloid following injury and over a person’s lifetime may play a role.”