Dementia Has a Link to Concussions

Dementia has a link to concussions, according to a recent Minnesota study of 70-year-old patients. Although past studies on this link have shown conflicting results, the patients who had memory problems and concussions that caused unconsciousness had more significant amounts of amyloid plaque on their brains than those whose concussions did not result in memory loss and thinking problems.

Amyloid plaques refer to protein deposits in the brains of Alzheimer’s disease patients. Alzheimer’s is a type of incurable dementia that usually affects adults over 65 years of age. Scientists have not determined the exact role plaque plays in the disease, but they likely contribute to the death of neurons and brain atrophy.

In 1906, the German scientist and physician, Alois Alzheimer, discovered plaque on brains that he studied. The plaque is called beta-amyloid peptides and is a type of protein that affects brain function. As plaque increases on the brain surface, the communication link between neurons is inhibited, and memory and thinking become difficult.

The Minnesota study was reported in Neurology, a journal published by the American Academy of Neurology. Michelle Mielke, PhD., led the team of scientists. Mielke stated that there is a link between those who experienced unconsciousness or plaque build-up of 18 percent or higher and Alzheimer’s, but a lot more research must be done to determine why these factors lead to Alzheimer’s disease. Dementia, therefore, has a link to concussions resulting in memory loss and thinking problems.

Brain scans were analyzed for all of the 448 Minnesota study participants. Seventeen percent of those who reported no memory issues had experienced a brain injury. Eighteen percent of those who had memory and thinking difficulties said they had a brain injury. For those whose brain scan showed 18 percent more plaque on the brain than those who had no brain injuries, they were stricken with dementia and Alzheimer’s disease.

“Interestingly, in people with a history of concussion, a difference in the amount of brain plaques was found only in those with memory and thinking problems, not in those who were cognitively normal,” Mielke said.

Scientists used to believe that beta-amyloid plaques actually caused dementia. In truth, plaque is a symptom of dementia, in which certain enzymes affect pre-cursor proteins. Some of these pre-cursor proteins develop beta-amyloid peptides, whereas others do not cause plaques.

There are other causes of plaque build-up in those who suffer from dementia. Dr. Joseph Masdeu, director of the Nantz National Alzheimer Center at Houston Methodist Hospital, said genetics play the biggest risk factor for Alzheimer’s. “If an immediate family member has it, the risk goes up four-fold,” he said.

Concussions can be tricky and there are factors that will increase the possibility of dementia in its victims. One of the biggest threats of concussions is second impact syndrome. This occurs when one concussion is still showing symptoms, and another concussion impacts the brain. In this case, the brain swells rapidly and can result in death.