Risk for Post Concussion Syndrome
Who is More at Risk Factors for Long Term Problems?
Concussion does indicate the beginning of a cascade of events, that may or may not damage sufficient neural connections to cause noticeable changes in the injured persons behavior over the first 12-72 hours. We cannot predict a “full recovery”, as opposed to an “apparent full recovery” based upon any snap shot of an injured persons function over such time frame. It may be that they were fully oriented during the period from one minute post trauma to time they left the ER, but that their cognitive and neurological function deteriorated thereafter. These patients may be at risk for post concussion syndrome.
If we were to require everyone with a concussion to return to the ER the next day, we would probably get a much better picture of who was having persisting problems than we get in the in the first hour or two after trauma. Unfortunately, in most concussion cases, the only time during the first 72 hours that a person is seen by a medical professional is in the first hour or two after trauma. Thus, we clearly cannot make any determination about severity from what is recorded in such person’s medical records.
We have known, far longer than we have known why, that certain individuals were significantly more at risk for post concussion syndrome and less than apparent full recovery.
Research has demonstrated, that even though almost all young people appear to have “apparent full recoveries”, that if their brains are put under sufficient stress, they have materially different performances than uninjured persons. See the treatment of Measuring Attentional Problems elsewhere on these pages. What these findings have explained is why those who are in particularly challenging professions, or who put exceptional demands on their brains ability to attend and process information, are at risk for noticeable deficit, even at a young age.
High achievers may achieve normal scores, “but not in a normal fashion.
Normal subjects do not need two hours of sleep after the test session to fully recover from the effort, nor do they need to take two to three days to recover fully.” Source: Gronwall, Dorothy in Levin, Eisenberg, Benton, Mild Head Injury,© 1989, Oxford University Press, at Ch. 10 pages 156-161.
We have also known that anyone over 40 is more at risk for post concussion syndrome and was unlikely to have an “apparent full recovery.”
Until recently, the reason for this wasn’t entirely clear, but with the discovery of the brains ability to regenerate damaged neuroconnections, we have learned that the growth factor which allows for such regrowth, has largely disappeared by the age of 40. Thus, what recovery that occurs is slower and apparently “incomplete”.
We also have known that people with a history of previous concussion, are at far greater risk for post concussion syndrome and a poor outcome.
Again, our recent advances in neuropathology are pointing us to the explanation that the regeneration of neuroconnections that does occur, is more fragile than the original connections. Thus, it takes less to cause more damage than it did with the first concussion.