A new study has found that chronic traumatic encephalopathy (CTE), a disease associated with repeat brain trauma, may initially present itself in two different ways: by affecting behavior or mood or by affecting memory and cognitive abilities.
CTE has been found in amateur and professional athletes, members of the military, and others who experienced repeated head injuries, including concussions and subconcussive trauma, according to researchers at Boston University School of Medicine.
For the study, scientists examined the brains of 36 male athletes, between the ages of 17 and 98, who were diagnosed with CTE after death. A majority of the athletes had played amateur or professional football, with the rest participating in hockey, wrestling or boxing.
Researchers also interviewed family members about the athletes’ lives and medical histories, including dementia, changes in thinking, memory, behavior, mood, motor skills and the ability to carry out daily tasks. The researchers also reviewed the athletes’ medical records.
The study found that 22 of the athletes had behavior and mood problems as their first symptoms of CTE, while 11 had memory and thinking problems as their first symptoms. Three of the athletes did not show any symptoms of CTE at the time of death.
The researchers report that those with behavior and mood problems experienced symptoms at a younger age, with the first symptom appearing at an average age of 35. That’s compared to an average age of 59 for those with memory and thinking problems.
Almost all of the people in the mood/behavior group — or 91 percent — experienced symptoms of memory and thinking decline at some point, according to the researchers.
On the flip side, the study found that only 55 percent of the athletes who experienced memory or cognition problems first also experienced behavior symptoms at some point, while 64 percent experienced mood symptoms.
The study also found that the athletes who experience mood symptoms were more explosive, out of control, physically and verbally violent, and depressed than the group that experienced memory and thinking deficits.
Family members reported that 73 percent of those in the first group were “explosive,” compared to 27 percent in the second group, according to the researchers.
Additionally, 64 percent of the first group were described as being “out of control,” compared to 27 percent of the second group, while 68 percent were physically violent, compared to 18 percent. Family members reported that 74 percent in the first group were verbally violent, compared to 18 percent in the second group.
Lastly, 86 percent of the athletes in the first group suffered from depression, compared to 18 percent of those with memory symptoms, the researchers discovered.
Study author Robert A. Stern, Ph.D., a professor of neurology and neurosurgery at Boston University School of Medicine, said that the findings should be viewed with caution. He noted that the overall number of cases in the study was small, adding “there may be more variations in CTE than described here.”
He also pointed out that there was no comparison group of former athletes without CTE in the study. In addition, families choosing to participate in the study may have been more likely to witness more severe symptoms than those not participating, which could have affected the results, he said.
Stern added that the findings suggest that the diagnosis of dementia in older individuals with a history of repeat brain trauma may be difficult because many of the symptoms of CTE are similar to other diseases, such as Alzheimer’s.
The study was published in Neurology.
Source: Boston University Medical Center