Researchers at Baycrest Health Sciences’ Rotman Research Institute found retired professional ice hockey players involved in their neuropsychological study were free from significant brain impairment on objective testing. However, these players reported a high level of emotional, behavioural and cognitive challenges.

The study, published in Journal of Neurology, Neurosurgery, and Psychiatry, began in 2010 and focused on retired athletes cognitive and behavioural functioning in relation to their age, concussion history, and genetic risk.

"There has been a lot of attention on repeated concussions and neurodegenerative disease, particularly in post-mortem samples of ex-athletes," said Dr. Levine in a statement. "There is a need for more comprehensive assessment of mental and behavioral changes during life. This longitudinal study will allow us to track changes over time to better understand aging and brain health in retired professional athletes."

As part of the study, thirty-three retired professional athletes, most of whom played in the NHL, were tested with 18 age-matched healthy males who had no history of professional contact sports as a comparison group. Participants underwent paper-and-pencil and computerized cognitive tests, questionnaires and brain imaging studies.

Retired NHL player, Scott Thornton, volunteered in the study because he was concerned about his memory function and wanted to know if it had anything to do with concussions he sustained during his professional hockey career.

"My hope is that this longitudinal study will help all hockey players and everyone involved in the game have open and honest conversations about the impact of head traumas," said Thornton. "Hockey is a very physical sport and a shoulder or leg injury is very different from a hit to the head. After an injury, we would often get back on the ice and continue to play, but it's important for everyone involved with the game to respect the consequences of these types of decisions."

Researchers found that the alumni and healthy group performed on a similar level on tests of attention and memory. However, there was a subtle disadvantage for the alumni on executive and intellectual functioning, with performance on these tests linked to the number of concussions sustatined in the retired athletes.

Blood samples tested for genetic analysis, with a focus on the APOE gene, was also provided by each participant. Researchers found that the APOE ε4 allele, linked with a higher risk of dementia in previous studies, was linked with psychiatric symptoms, such as depressed mood, but not cognitive changes. Longitudinal testing will need to be done for a more concrete answer of this finding.

The team of Baycrest researchers will continue this study by working on a series of related papers reporting extensive brain imaging data. This is a longitudinal study in which players will be tested every four years and will also have the option to donate their brains to science posthumously for neuropathological confirmation of potential brain diseases.