PARIS, July 18 (UPI) -- A screening of 513 retired National Football League players found they were at higher risk for mild cognitive impairment, U.S. researchers say.
"It appears there may be a very high rate of cognitive impairment in these retired football players, compared to the general population in that age range," neuropsychologist Christopher Randolph of Loyola University Chicago Stritch School of Medicine says in a statement.
People with mild cognitive impairment have trouble with memory, language or other mental functions, which are noticeable and show up on tests, but are not severe enough to interfere with daily living, Randolph says. People who have mild cognitive impairment are at higher risk for developing Alzheimer's disease.
The study found 35 percent of the retired NFL players had mild cognitive impairment -- which can be a precursor to Alzheimer's disease, Randolph says.
The findings of his study suggest that repetitive head trauma from years of playing football may result in diminished brain "reserve" and thus lead to earlier expression of age-related degenerative diseases such as mild cognitive impairment and Alzheimer's, Randolph says.
"However, it would take additional studies to confirm this," Randolph says in a statement. "So for now, these studies should be considered very preliminary."
The findings were presented at the Alzheimer's Association International Conference in Paris.