Head trauma and in vivo measures of amyloid and neurodegeneration in a population-based study

Neurology (Impact Factor: 8.29). 12/2013; 82(1). DOI: 10.1212/01.wnl.0000438229.56094.54
Source: PubMed


We determined whether head trauma was associated with amyloid deposition and neurodegeneration among individuals who were cognitively normal (CN) or had mild cognitive impairment (MCI).
Participants included 448 CN individuals and 141 individuals with MCI from the Mayo Clinic Study of Aging who underwent Pittsburgh compound B (PiB)-PET, fluorodeoxyglucose-PET, and MRI. Head trauma was defined as a self-reported brain injury with at least momentary loss of consciousness or memory. Regression models examined whether head trauma was associated with each neuroimaging variable (assessed as continuous and dichotomous measures) in both CN and MCI participants, controlling for age and sex.
Among 448 CN individuals, 74 (17%) self-reported a head trauma. There was no difference in any neuroimaging measure between CN subjects with and without head trauma. Of 141 participants with MCI, 25 (18%) self-reported a head trauma. MCI participants with a head trauma had higher amyloid levels (by an average 0.36 standardized uptake value ratio units, p = 0.002).
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. Differences between CN individuals and individuals with MCI raise questions about the relevance of head injury-PET abnormality findings in those with MCI.

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    • "No difference in any neuroimaging measure between cognitive normal subjects with and without head trauma was found. However, of 141 participants with mild cognitive impairment (MCI), participants with a head trauma had higher amyloid levels (by an average 0.36 standardized uptake value ratio units, p ¼ 0.002), suggesting that head trauma may be associated with Alzheimer's disease-related neuropathology (Mielke et al., 2014). However, a smaller study found amyloid-b deposition with PET scan in 3 of 12 subjects with posttraumatic neuropsychological impairment (Kawai et al., 2013). "
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    • "MMSE might be not adequately sensitive enough to detect extremely mild cognitive impairment, especially for people with prior high cognitive function. However, this finding could be comparable with previous studies, either in case–control studies or cohort studies on health care database analysis [35]. Although the clinical manifestations were similar among the mTBI − D and mTBI + D groups, the ILOC appears to be a risk factor for the subsequent development of dementia in mTBI patients (5/6 vs. "
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