WEDNESDAY, Nov. 3 (HealthDay News) -- The rate of concussions among teen and young adult hockey players is more than three times higher than previously believed, and the issue needs to be taken more seriously by players, parents, coaches and doctors, researchers warn.

The study of 67 male ice-hockey players, aged 16 to 21, on two fourth-tier teams was conducted during the 2009-2010 hockey season. During 52 games, 17 players suffered a total of 21 concussions.

The Canadian researchers calculated that the incidence of concussions was 21.5 per 1,000 athlete exposures, which is 3.3 times higher than reported in previous studies.

Among the other findings:

Five of the 17 players (29 percent) with a diagnosed concussion suffered a second or recurrent concussion during the study period.

Fifteen of those 17 players (88 percent) said they had suffered at least one previous concussion.

Two of the players who suffered a concussion during the study period admitted that they had concealed a concussion sustained during that season in order to keep playing.

Of the 21 diagnosed concussions in the study, 71 percent were suffered by forwards and 29 percent by defensemen. There were no concussions among goalies.

Fifty-seven percent of the concussions occurred in the third period, 29 percent in the second period, and 14 percent in the first period.

Twenty-four percent of the concussions occurred in players who were personally involved in a fight right before their diagnosis.

On average, it took 12.8 days for 15 of the players diagnosed with concussion to return to play.

Players assigned to a concussion education group showed improved knowledge about the issue.

The findings are published in the November issue of Neurosurgical Focus.

"The aftermath of a concussion can impact memory, judgment, social conduct, reflexes, speech, balance and coordination," study author Dr. Paul Sean Echlin, of the AIM Health Group, Family Medicine in South London, Ontario, said in an American Association of Neurological Surgeons news release.

"Epidemiological studies have suggested an association between sport concussions and both immediate and later-life cognitive impairment. As such, this is a public health issue that needs to be taken more seriously by players, parents, coaches and medical professionals," he added.

However, this study found "a disturbing lack of compliance by the athletes to undergo requested neuropsychological evaluations and multiple physician visits, as well as a lack of understanding about the seriousness of concussion," study co-author Dr. Charles H. Tator, of Western Hospital, University of Toronto, said in the news release.

"Complaints from players, coaches and parents about this testing gave further credence to the importance of raising awareness about the serious long-term implications of concussions through education, which does appear to be beneficial according to our findings," he noted.

"The reluctance to report concussion symptoms may result from cultural factors, as expressed in several of the case studies -- athletes demonstrate perceived toughness to their parents, coaches, teammates and peers by playing through an injury; and the belief of the athlete that he or she is invincible, so winning overrides any consideration of the effect of the injury upon long-term health," Echlin said.

"It is imperative to bring about a cultural and philosophical change in this regard through stepped-up education efforts and enforcement of concussion protocols. At risk is something far more precious than winning a game, and that is the future health and well being of thousands of young athletes," he concluded.

More information

The American Academy of Family Physicians has more about sports concussions.