New Study Detects Relationship Between Head Trauma and Alzheimer’s Disease

Researchers from the Mayo Clinic have discovered a possible link between a history of head trauma and Alzheimer’s disease (AD) in individuals with mild cognitive impairment (MCI). In the study, patients with MCI who experienced a head trauma that resulted in loss of consciousness or memory had higher levels of AD-related amyloid plaques in the brain than those with no history of head trauma.

Lead researcher Michelle M. Mielke, PhD, Mayo Clinic, Rochester, MN, and colleagues performed brain scans (Pittsburgh compound B-positron emission tomography [PET], fluorodeoxyglucose-PET, and magnetic resonance imaging) on 589 patients (>70 years) from the Mayo Clinic Study of Aging. Among the participants, 448 were cognitively normal (CN) and 141 patients had MCI. The patients were also asked about their history of head trauma involving at least momentary loss of consciousness or memory. Head traumas were reported in 18% of individuals with MCI (n=25) and in 17% of CN individuals (n=74).

Mielke and associates found that those with MCI who had experienced a head trauma had levels of amyloid plaques that were an average of 18% higher than those with MCI who did not have a history of head trauma. Conversely, they detected no differences in any neuroimaging measure among CN patients with and without head trauma. “Among individuals with MCI, but not CN individuals, self-reported head trauma with at least momentary loss of consciousness or memory was associated with greater amyloid deposition, suggesting that head trauma may be associated with Alzheimer disease–related neuropathology,” the authors conclude. “Differences between CN individuals and individuals with MCI raise questions about the relevance of head injury–PET abnormality findings in those with MCI.” The full text of this study and its funding information is available in Neurology.

-Meredith Edwards White

Reference

Mielke MM, Savica R, Wiste HJ, et al. Head trauma and in vivo measures of amyloid and neurodegeneration in a population-based study. Neurology. 2014 Jan 7;82(1):70-76. doi: 10.1212/01.wnl.0000438229.56094.54. Epub 2013 Dec 26.