Ex-NFL players who had concussion symptoms performed worse on cognitive tests decades after retirement: Boston study

Former NFL players who reported experiencing concussion symptoms while playing were more likely to perform worse on a series of cognitive tests decades after retirement, according to Boston researchers who studied more than 350 retired players.

When comparing the 350 former pro players to more than 5,000 men in the general population, cognitive performance was generally worse for retired players compared to the non-players, the Mass General Brigham scientists found in the new study.

The ex-players who had concussion symptoms during their careers scored worse on assessments of episodic memory, sustained attention, processing speed and vocabulary. They were studied an average of 29 years after their playing careers ended.

These results are the latest evidence of pro football’s impact on accelerating cognitive aging, said the researchers who stressed that more studies are needed to track cognitive performance in former players as they age.

“It is well-established that in the hours and days after a concussion, people experience some cognitive impairment. However, when you look decades out, the data on the long-term impact have been mixed,” said study senior author Laura Germine, director of the Laboratory for Brain and Cognitive Health Technology at McLean Hospital.

“These new findings from the largest study of its kind show that professional football players can still experience cognitive difficulties associated with head injuries decades after they have retired from the sport,” added Germine, who’s also an associate professor of psychiatry at Harvard Medical School.

This new research is part of the ongoing Football Players Health Study at Harvard University.

For the study, 353 retired NFL players completed hour-long neuropsychological tests through an online platform called TestMyBrain.

The players were asked about the number of times they had the following symptoms after a blow to the head during a game or practice: headaches, nausea, dizziness, loss of consciousness, memory problems, disorientation, confusion, seizure, visual problems, or feeling unsteady on their feet.

The researchers found that the former players’ cognitive performance was tied to concussion symptoms. For example, differences in visual memory scores between former players with the highest and lowest reported concussion symptoms were the same as the differences in cognitive performance between a typical 35-year-old and 60-year-old man.

However, poor cognitive performance was not associated with diagnosed concussions, years of professional play or age of first football exposure. The researchers noted that many head injuries or sub-concussive blows may not have been diagnosed as concussions due to a lack of awareness at the time or underreporting of symptoms by players.

When comparing the retired players to a group of 5,086 men who did not play football, cognitive performance was generally worse for former players.