According to a recap published on Medscape that discussed the results of a recent study, traumatic brain injuries are not associated with the development of Alzheimer’s Disease later in life but are instead linked to the development of Parkinson’s Disease later in life. The new study suggests that traumatic brain injuries can be linked to the accumulation of Lewy bodies, which are associated with Lewy Body Dementia and Parkinson’s Disease according to the National Institutes of Health’s National Institute on Aging. Lewy bodies are abnormal protein deposits in the brain that can affect certain chemical levels in the brain, which can eventually lead to problems with thinking, movement, behavior, and mood. Ultimately, these affect a person’s ability to function normally on a day-to-day basis and may lead to Parkinson’s Disease or Lewy Body Dementia.
The study, published this month, contradicts an influential study from 1995 that had previously linked some aspects of traumatic brain injury with Alzheimer’s Disease. According to the lead author of the new study, the researchers had set out to prove the link between traumatic brain injuries and Alzheimer’s Disease later in life. According to the article, they instead found that a single blow to the head that resulted in the victim losing consciousness for more than one hour increased the risk of developing Parkinson’s Disease later in life by three-fold. The new study used data collected from three other studies that included participants initially free from dementia. The participants in the three other studies included older Seattle-area Group Health members; older religious clergy from across the United States; and older residents from the Chicago-area enrolled in the study through retirement facilities, subsidized housing, church groups, and social services. Having included thousands of older adults in the three studies used to conduct the study at hand, no particular link was found between the occurrence of traumatic brain injuries with loss of consciousness over one hour and Alzheimer’s Disease. Researchers indicated that they found a “pretty strong” association between loss of consciousness lasting more than an hour and the risk of developing Lewy bodies based on comprehensive neuropathic evaluations conducted at the time of death. The research indicated an average 40-year gap between a traumatic brain injury with loss of consciousness over one hours and the development of microscopic evidence of abnormal proteins associated with Lewy bodies.