The latest study shedding light on CTE causation was published this week in the Journal of Neurotrauma. In short the study suggests CTE is caused by repeted brain rattling activities and not individual concussions or even individual moderate to severe brain injuries.
In the study, titled Lack of Association of Informant-Reported Traumatic Brain Injury and Chronic Traumatic Encephalopathy, the researchers examined data from 580 deceased individuals who were exposed to repeated brain rattling from football. CTE was found in 405 of these individuals. Among the participants 213 reported at least one Traumatic Brain Injury without loss of consciousness. 345 had at least one brain injury with loss of consciousness and of those 36 had at least one moderate to severe brain injury. 22 participants had no reported past traumatic brain injury.
The data was drilled down to see if there was any association between those with past traumatic brain injuries and CTE. They found they “were not associated with CTE”.
In short this study points to the repeated brain rattling being the cause of the disease, not individual traumatic brain injury events.
The full abstract reads as follows:
Repetitive head impacts (RHIs) from football are associated with the neurodegenerative tauopathy chronic traumatic encephalopathy (CTE). It is unclear whether a history of traumatic brain injury (TBI) is sufficient to precipitate CTE neuropathology. We examined the association between TBI and CTE neuropathology in 580 deceased individuals exposed to RHIs from football. TBI history was assessed using a modified version of the Ohio State University TBI Identification Method Short Form administered to informants. There were 22 donors who had no TBI, 213 who had at least one TBI without loss of consciousness (LOC), 345 who had TBI with LOC, and, of those with a history of TBI with LOC, 36 who had at least one moderate-to-severe TBI (msTBI, LOC >30 min). CTE neuropathology was diagnosed in 405. There was no association between CTE neuropathology status or severity and TBI with LOC (odds ratio [OR] = 0.95, 95% confidence interval [CI] = 0.64–1.41; OR = 1.22, 95% CI = 0.71–2.09) or msTBI (OR = 0.70, 95% CI = 0.33–1.50; OR = 1.01, 95% CI = 0.30–3.41). There were no associations with other neurodegenerative or cerebrovascular pathologies examined. TBI with LOC and msTBI were not associated with CTE neuropathology in this sample of brain donors exposed to RHIs from American football.
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