An athlete who returns to play before having completely recovered from a concussion is three to five times more likely to sustain another one. If a new concussion occurs before the brain has fully healed from the previous one, sequela of this new concussion could be even worse, the recovery could be longer and, in rare cases, consequences could be catastrophic. Changes do occur in the brain after a single concussion. However, the long term effects will be minimal if properly cared for and the necessary rest is taken. This being said, concussions do have a cumulative effect. Each new concussion causes a little more damage to cerebral tissues and, on average, damage will become permanent after three concussions. This damage can significantly affect certain functions of the brain.
Many studies demonstrate a direct correlation between the number of concussions sustained and their clinical consequences. This is where athletes distinguish themselves from the rest of the population. Many athletes practicing collision or contact sports can accumulate 5 to 10 concussions in a period of only 5 to 10 years. Athletes having experienced repeated brain trauma will manifest twice as many symptoms as ones who have only sustained one and will experience a longer healing process. Those with a history of three or more concussions also report headaches and post-trauma amnesia more frequently.
Consequences of multiple concussions on brain tissue can include:
These disturbances of brain function might be at the root of chronic symptoms and persisting cognitive deficits in individuals suffering from Post-Concussion Syndrome. Symptoms related to these cerebral disturbances can include:
There is scientific data that leads us to believe that the accumulation of concussions negatively affects the normal ageing of the brain. The brain of the individual having experienced multiple concussions will not only age faster, but will show signs of degenerative brain disease that can resemble Alzheimer’s disease. For example, studies show the prevalence of pre-Alzheimer’s syndrome is five times as high in athletes having accumulated at least three concussions.