BOSTON—New research is calling into question whether traumatic brain injury is actually a risk factor for Alzheimer’s disease.

A report in the journal Alzheimer’s & Dementia discussed recent research with neuropathologic or biomarker evidence of Alzheimer’s disease and said it casts doubt on whether TBI includes risk of AD.1

Study authors from Edith Nourse Rogers Memorial Veterans Hospital, the VA Boston Healthcare System and Boston University took a close look at the association between self-reported TBI with loss of consciousness and AD neuropathologic changes, as well as with baseline and longitudinal clinical status.

To do that, researchers used 4,761 autopsy samples—453 of the participants had remote TBI with loss of consciousness, while 2822 had AD neuropathologic changes—from the National Alzheimer’s Coordinating Center.

Results indicated that self-reported TBI did not predict AD neuropathologic changes (P>0.10). Furthermore, the study team determined that reported TBI was not associated with baseline or change in dementia severity or cognitive function in participants with or without autopsy-confirmed AD.

“Self-reported TBI with loss of consciousness may not be an independent risk factor for clinical or pathological AD,” the study authors wrote. “Research that evaluates number and severity of TBIs is needed to clarify the neuropathological links between TBI and dementia documented in other large clinical databases.”

Sugarman MA, McKee AC, Stein TD, Tripodis Y, et. Al. Failure to detect an association between self-reported traumatic brain injury and Alzheimer’s disease neuropathology and dementia. Alzheimers Dement. 2019 May;15(5):686-698. doi: 10.1016/j.jalz.2018.12.015. Epub 2019 Mar 7. PubMed PMID: 30852157; PubMedCentral PMCID: PMC6511462.