American researchers have set out to determine if a traumatic brain injury with loss of consciousness increases a person’s chance of developing degenerative brain diseases or dementia as older adults, including Parkinson’s and Alzheimer’s. The scientists found an association between the two, but were unable to explain why the connection exists, though future research might provide more conclusive details.
They speculate that perhaps the actual head injury leads to Parkinson’s, or that someone who sustains a head injury and was already going to develop Parkinson’s might have a more difficult time of adjusting to the effects of the disease as it progresses. But the study didn’t determine that a brain injury necessarily leads to Parkinson’s disease.
For the study, data on over 7,000 people with an average age of 80 was collected between 1994 and 2014; 865 people from this group had sustained a traumatic brain injury with loss of consciousness. Of this group, 1,500 had dementia and 117 had Parkinson’s.
Parkinson’s disease is a neurodegenerative disorder that affects the central nervous system, and therefore the movement of the body. It’s more common in older adults, but can sometimes strike people of younger ages, most famously in the case of actor Michael J. Fox. Sufferers progressively lose control over the movements their bodies make (or, the body moves involuntarily), and the symptoms will worsen with time; tremors are the hallmark of this disease.
There is no cure for Parkinson’s and the cause is unknown. Almost 1 million Americans currently suffer from the disease. Treatment options, mostly in the form of pharmaceuticals, are available to help manage the disease. Having suffered a traumatic brain injury early on may possibly be a contributing factor to developing Parkinson’s and other forms of dementia as older adults, though further studies need to be done to determine this conclusively.
Crane P.K., et al., “Association of Traumatic Brain Injury with Late-Life Neurodegenerative Conditions and Neuropathologic Findings,” JAMA Neurology, 2016; doi: 10.1001/jamaneurol.2016.1948.