Sports Medicine Research: In the Lab & In the Field: Undiagnosed Concussions Are Associated with Loss of Consciousness (Sports Med Res)


Thursday, June 20, 2013

Undiagnosed Concussions Are Associated with Loss of Consciousness

The prevalence of undiagnosed concussions in athletes

Meehan WP, Mannix RC, O’Brien MJ, Collins WC. Clinical Journal of Sports Medicine. 2013; ahead of print.

Take Home Message: Over 30% of athletes reported a previously undiagnosed concussion and these athletes may be at risk for more severe symptoms after a future impact.

Many athletes fail to report their concussion signs and symptoms (Kauet, 2003 Labotz,2005; McCrea,2004; Williamson, 2006), which predisposes them to sustaining a second blow when the brain is still recovering from the first impact. However, we still don’t know how common undiagnosed concussions may be. Identifying under-reporting rates will help medical personnel clarify where additional measures can be taken to ensure athletes’ safety. Therefore, the purpose of this study was to determine whether patients from 2 sport clinics sustained previous concussions that went undiagnosed. The authors evaluated 486 patients that were seen between October 2009 and September 2010 due to a sports-related concussion. The patients provided demographic (e.g., age, gender) and clinical information (e.g., day of injury, sport), and completed the Post Concussion Symptom Scale (part of the Sport Concussion Assessment Tool 2). Then, they answered the following question: “Have you ever sustained a blow to the head which was not diagnosed as a concussion, but was followed by one or more of the signs and symptoms in the Post Concussion Symptoms Scale?” The patients answering yes to this question were defined as having a previously undiagnosed concussion. A total of 148 (30%) patients reported that they had sustained a blow to the head that resulted in concussion signs and symptoms, but were never diagnosed with a concussion. There were no differences in gender, age, or number of previous concussions between those that reported an undiagnosed concussion to those that did not. Athletes who reported a previously undiagnosed concussion were more likely to have lost consciousness with their current injury compared with those with no previously undiagnosed concussion (30.6% vs. 21.8%). Also, athletes that reported undiagnosed concussion had a higher initial Post Concussion Symptom Scale score (mean = 33) with their current injury compared to patients that did not report a previously undiagnosed concussion (mean = 25).

Nearly one-third of the athletes seen at the 2 sport clinics reported previously undiagnosed concussions. This rate is lower than previous research, which may be due to the inclusion of all sports and not just football athletes, who may less likely to report their concussions. It could also be attributed to the increased media attention and improved education that resulted in more athletes reporting their concussion symptoms. However, 30% is still an alarming rate of undiagnosed concussions. Additionally, those athletes with previously undiagnosed concussions had more symptoms and higher rates of loss of consciousness with their current injury compared with athletes without a previously undiagnosed concussion. Failure to report concussion signs and symptoms may increase the risk of deleterious effects on the brain. A prospective study designed to determine the reasons behind the undiagnosed concussions may allow researchers to educate athletes to seek proper medical attention. In the meantime, we must be aware that almost a third of concussions may be missed and that these athletes may be at risk for more severe symptoms after a future impact. This may be valuable information when we educate our athletes, coaches, and parents about the consequences of missed concussions.

Questions for Discussion: What do you think the best method is to deliver concussion education to the public? Other than education how can we reduce the number of undiagnosed concussions?

Written by: Jane McDevitt PhD, ATC, CSCS
Reviewed by: Jeffrey Driban

Related Posts:
Coaches Influence the Reporting of Concussive Symptoms among High School Athletes

Meehan WP 3rd, Mannix RC, O╩╝brien MJ, & Collins MW (2013). The Prevalence of Undiagnosed Concussions in Athletes. Clinical Journal of Sport Medicine PMID: 23727697


Anonymous said...

This brings up an important issue in sports that has just recently received a lot of attention from the media. Second impact syndrome can be fatal but is always preventable. Athletes, parents, coaches, and referees need to be educated on the severity of undiagnosed concussion so they can truly understand the severity of this injury. The amount of undiagnosed concussions would hopefully decrease if there were more certified athletic trainers present in high schools and youth sports. ATCs are trained in recognizing the signs and symptoms of concussions. They are able to give the concussed athlete a neurocognitive test that helps determine when the athlete is no longer experiencing any adverse effects as a result of the concussion. After this, the ATCs are able to create a gradual return to play protocol to safely return the athlete to full participation without the risk of developing second impact syndrome. By having more ATCs in high schools and with youth sports, the number of reported concussions may increase. However, this would hopefully decrease the number of undiagnosed concussions which is a much more serious problem.

Lauren Rao, ATC said...

It's incredibly disheartening to see so many concussions go undiagnosed though not surprising. Currently, the seriousness of concussions is still somewhat underrepresented in my opinion. Education has been increasing, but it hasn't been increasing fast enough. There are still many states whose concussion laws are less than adequate and many schools don't offer education programs. I think it is necessary to implement some kind of concussion education program in any setting, whether it be schools, professional setting, or even youth leagues. The best way to make sure parents and athletes are educated, I'm not sure. Sending papers home to sign means they usually don't get read, while other people might not show up to a mandatory meeting. I am still astonished that we have criteria to play such as physicals and health insurance forms, but understanding something as serious as a mild traumatic brain injury is not included. Athletes of all ages need to recognize what a concussion feels like and the grave importance of reporting signs and symptoms to coaches or athletic trainers.
This being said, I also think that we, as clinicians, need to do a much better job at recognizing signs and symptoms off the field. We are very attentive during practice or at games at watching for collisions and being wary of any injury that may occur. Indoors, however, it seems that our minds are not on concussions. We need to pay attention to athletes and listen for signs and symptoms of mild traumatic brain injury. Overall, concussion education and awareness is heading in the right direction, but I think it needs to happen faster.

ZJ said...

30 percent is a frightening number. When thinking from a risk management standpoint, this is way too many athletes who are putting their brains, and potentially their lives at risk. Studies such as this one can help us prove that there is a problem with the reporting of concussions, and that it needs to be addressed.
Concussions are at the forefront of sports medicine and athletics. The amount that sports medicine knows about concussions is continuing to grow. With this knowledge, there must be constant communication to educate the public about the risks and dangers of traumatic brain injuries.
Concussion education is based on communication with the public. This needs to start at the earliest levels possible, and at areas that reach the most people possible. As Lauren said, there needs to be more done than just sending papers home for parents to sign. The best ways to communicate take time and/or money. This means that for the most part, we need to put more time and effort in communicating with parents and athletes about the risks they are taking, and the consequences of these risks. You can be proactive with parent meetings, types of flyers given out during PPEs, school board meetings, and preseason player meetings as well.
I believe that there is still tons more to find in researching concussions and brain injuries, and until we learn much more, we do not know where a plateau will be set for undiagnosed concussions. For now, we can continue to work at educating the public in whatever ways possible to lower these rates.

Jane McDevitt said...

I agree that 30% is an alarming amount of concussions to go untreated; however this number has not decreased. It was has been estimated anywhere between 25-34% of concussions go unreported since 2001. Even with the recent efforts to distribute and make people aware of concussions it does not seem to be working. I agree with the previous posts that signing flyers does not seem to be working because the public are probably not reading them. Also, the severity of concussion injuries and possible long term effects does not seem to be not well understood by the public. I think ZJ made a good point that medical professionals need to step up their communication and use as many platforms as possible. I feel like face to face forums are necessary so there can be question and answer, but as Lauren has suggested if there is just 1 mandatory meeting attendance is not going to be 100% and we need to reach as many people as possible.

Stephanie Huntsman said...

First off, let me begin by echoing the above sentiments that over 30% of concussions remain undiagnosed is frightening, and hopefully provokes a significant increase in our already increasing awareness of mTBIs. Unfortunately, this is not a surprising statistic, for three reasons: we are still in that transitionary period between a "non-severe 'getting your bell rung'" mentality, athletes (and their coaches, parents, teammates, etc.) may be unaware of or unable to recognize their symptoms, and many athletes attempt to conceal symptoms in order to avoid loss of time in sport. After attending the latest NATA meeting, it was encouraging to see the number of helmet-based sensors for detecting potentially concussive forces; a major downside to these is the price, unfortunately (As well as inaccurate readings with respect to the direction of said force.) To implement something of this sort (it would be interesting to see if even using a "placebo" device as a "scare tactic" might increase self-reporting) would, I feel, not only increase awareness of the forces occurring, but as I just stated, also potentially increase self-reporting of symptoms. As also mentioned above, education is key. By educating the parents of athletes, the friends and teammates of athletes, the coaches of athletes, and the athletes themselves, we are increasing awareness, recognition, and if executed well, a network which looks out for each other (A bit too ideal, but we can all dream, right?!) Beyond the symptom recognition, effect on academics, as well as long-term effects, Second Impact Syndrome needs to continue to be out there as a very real risk.

Jane McDevitt said...

I think your idea on using the helmet sensor as a placebo effect as a scare tactic could work. That would be an interesting research idea! I am not that fond of the current helmet sensors on the market. I feel like the for the helmet sensor to be a functional research tool it would need to encase the entire helmet. However, that would be very expensive let alone the computers and software necessary to pull the data off the helmet. I also liked your comment about the slang terms for a concussion. I recently did a survey study (unpublished) and there was an alarming rate of athletes that reported getting their bell rung and did not report a history of a concussion. That slang terminology needs to be taught that getting your bell rung is a possible concussion. And, now we are back to education. Education is the key and I liked how you said it is a network that needs to work together. Not only the athletic trainers, coaches and parents, but the athletes themselves need to look out for one another.

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