New Strategies Show Promise for Concussion

Figure: concussion, treatment, brain injury, supplements, exercise, cooling, irritability, headache, nausea, insomnia, forgetfulness, light sensitivity, vertigo, blurry vision, brain fog, symptomsFigureFigureResearchers are studying supplements, exercise, and cooling to treat brain injury Irritability, headache, nausea, light sensitivity, forgetfulness, insomnia. We tell parents to look for these post-concussive symptoms. (They are also what emergency physicians experience after too many night shifts.) Vertigo, brain fog, blurry vision. Yes, it is a long list, and every concussion is different. Difficulty finding words. Yes, this might be difficult to discern from baseline in a 16-year-old. Rest, limit activities that make symptoms worse, avoid too much screen time, and don't return to play until cleared. Sorry, there is no definitive treatment. Concussions have myriad symptoms and can vary greatly in duration and severity. Once dismissed as a temporary affliction with a veneer of masculinity and toughness (“He got his bell rung!”), concussion is now seen as a major public health challenge. The Centers for Disease Control and Prevention estimated that 2.8 million head injury ED visits occurred in the United States in 2013. (MMWR Surveill Summ. 2017;66[9]; https://bit.ly/3JgO8qR.) Nearly 300,000 of these (10%) affect children and adolescents who sustain concussions during sports. The pendulum has swung in recent years about awareness and diagnosis. Watch even one quarter of an NFL game and you are likely to see at least one player escorted into the blue tent for a neurological assessment by a physician. We've also made progress with prevention, especially in children under 17 playing contact sports, resulting in 32 percent fewer ED visits for sports-related head injuries between 2012 and 2018. (MMWR Morb Mortal Wkly Rep. 2020;69[27]:870; https://bit.ly/3JfnvSX.) We encounter patients in the ED at particularly uncertain and challenging points in the gamut of concussion pathology. We recognize that concussions usually aren't difficult to diagnose but are hard to predict and nearly impossible to treat, with nearly as many proposed treatments and studies as there are symptoms. The only firm recommendation until recently, however, was physical and mental rest. Recent evidence has questioned this beyond the short term, and luckily, there are promising, easily accessible alternatives. Supplements It would be convenient if there were a cheap, readily available, and safe nutritional supplement for concussion, but the evidence hasn't identified one, despite what marketers would like you to believe. Certain supplements—omega-3 fatty acids, vitamins C, D, and E, curcumin (found in turmeric), resveratrol, melatonin, and creatine—have been studied but not shown benefit in humans with concussions. Future investigations may change this: Two clinical trials are starting, one on the effect of omega-3 and vitamin D plus creatine on persistent post-concussion symptoms and one on melatonin in acute pediatric concussion. A small, randomized trial of N-acetylcysteine in older adults with mild traumatic brain injury also recently demonstrated improvement in post-concussion symptom scores seven and 30 days after injury. (J Trauma Acute Care Surg. 2022;93[5]:644; http://bit.ly/3R0yNwn.) Sleep disturbances are common after concussion, and many symptoms (like trouble concentrating and irritability) mirror those of sleep deprivation, so perhaps a sleep aid can help treat concussion. At the very least, melatonin is unlikely to cause harm in post-concussive insomniacs. Exercise Wouldn't it be great if a simple intervention like moderate exercise could help speed recovery? Good news! Moderately convincing evidence has shown that the early initiation of targeted exercise can make a positive difference. The physiological concept here is that aerobic exercise increases blood flow to the brain, which in turn helps with oxygen delivery and producing brain-derived neurotrophic factor to stimulate neuron growth and enhance neuroplasticity. Several studies demonstrated the benefit of post-concussive exercise using the hypothesis that such neuro-processes could help the brain recover after concussive injury. One study was even titled “Exercise is Medicine for Concussion.” (Curr Sports Med Rep. 2018;17[8]:262; http://bit.ly/3j4K0PV.) The old post-concussion return-to-sport protocols recommend a week or more of strict rest, but the new consensus is that exercise can start almost immediately if done with constraints. The goal is subsymptom threshold aerobic exercise, which means a concussed athlete tests her tolerance on a treadmill, stationary bike, or similarly safe activity by tracking her heart rate. She dials back if symptoms worsen until her heart rate is roughly 10 percent slower and then exercises for about 30 minutes. This work demonstrated that this regimen can speed recovery by four days or more, at least in adolescents. (JAMA Pediatr. 2019;173[4]:319; http://bit.ly/3DcY2WB.) Beyond aerobic exercise, there may also be a benefit of physical therapy interventions, in certain patients at least. This might be considered in those with vestibular symptoms. A systematic review published earlier this year screened more than 7000 studies to find eight high-quality investigations (including the two above [Curr Sports Med Rep and JAMA Pediatr] from well-known concussion researcher John J. Leddy, MD, from the State University of New York at Buffalo) into the benefits of physical therapy interventions for adolescent and young adult athletes post-concussion. (Int J Sports Phys Ther. 2023;18[1]:26; http://bit.ly/3ZDRJni.) They concluded that multimodal approaches to post-concussion rehabilitation, in addition to moderate aerobic exercise, were likely beneficial for youths and adolescents with concussion. These supplemental recovery-enhancing modalities may include coordination and balance activities, visualization techniques, and cervical spine and vestibular rehabilitation. Stimuli Management What if the best way to treat concussions is to confine the concussed individual in a dark noiseless room? That sounds just awful. But, as we know, strict stimuli mitigation—no exercise, school, screens, or fun at all—was once recommended for concussed patients. Fortunately for this generation of youngsters, the treatment is no longer worse than the condition, at least not by such a degree. Recently published guidelines allow for gradual increase in typical activities such as texting, reading, and screen time as soon as 24 hours after a concussion as long as these do not exacerbate symptoms. (JMIR Pediatr Parent. 2022;5[2]:e36317; http://bit.ly/3ZEcr6l; CJEM. 2021;24[1]:12; http://bit.ly/415ECw2.) We know that bright lights and loud noises can be irritating to just about everyone and even more so to those with head injuries. Without much evidence other than common sense, guidelines also give a soft recommendation for ear plugs or noise-cancelling headphones and sunglasses. Thermal Treatment What about a treatment that could be started immediately after head trauma to prevent or mitigate concussion symptoms? Our response is not as frosty as you might expect. A recent study examined immediate head and neck cooling for concussed ice hockey players. (J Neurotrauma. 2022; doi: 10.1089/neu.2022.0248; https://bit.ly/3iVzjiF.) We know that increasing temperature after an injury can be deleterious, causing more inflammation and cellular damage, which is why we ice sprained ankles and run cool water over burns.Figure: Two football players were imaged before the football season; the concussed player was imaged again within a week of his concussion, the control player again at the end of the season. Colored areas show cortical and subcortical regions of significantly greater activation in the concussed player compared with the nonconcussed one.The researchers in this study tested whether the same principle might apply to injured brains and used a protocol of 45 minutes of immediate cooling with a head and neck cooling cap to measure its impact on time to return to play. The investigators enrolled adult male hockey players (average age 26) over five years with 132 sport-related concussions, and found those in the cooling group returned to play in nine days while those receiving standard post-concussion care went back in 13 days, a four-day difference quite similar to what was seen in the subthreshold exercise study. This is promising, but it would be challenging to replicate broadly because the cooling cap is more technologically nuanced than an ice pack. The authors said it uses a high-powered portable cooling system with a circulating coolant maintained at 0°C that flows through a silicone cap with an insulated neoprene cover. It doesn't seem far-fetched to have such systems in the NFL's blue tent, but it would be a stretch to have them on the sidelines of tens of thousands high school fields. The cap was also applied extremely quickly, only 10 minutes after injury in the study, so teen sports would need it on the sidelines, and coaches and parents would need to make the decision to use it stat. Maybe delayed cooling could be beneficial too, but that is unlikely: You can't unboil an egg. Collision. Clock cleaning. Header. Knock out stage. The vernacular of head trauma is omnipresent in sports and so are concussions in our health care system. There is still much to be done to wrap our heads around this challenging condition, but there have been advances, and we think we can look forward to more. Consensus on Concussion The International Conference on Concussion in Sport was expected to release a consensus statement this spring summarizing the current literature that could be used to prevent, detect, and manage sport-related concussions, but it was not available at press time. Find more information at https://bit.ly/3zA0KTD. DR. VINSON is an emergency physician at Kaiser Permanente Sacramento Medical Center, a chair of the KP CREST (Clinical Research on Emergency Services and Treatment) Network, and an adjunct investigator at the Kaiser Permanente Division of Research (https://www.kpcrest.net/). DR. BALLARD is an emergency physician at San Rafael Kaiser, a past chair of the KP CREST Network, and the medical director for Marin County Emergency Medical Services. Read their past articles at http://bit.ly/EMN-MedClear. Share this article on Twitter and Facebook. Access the links in EMN by reading this on our website: www.EM-News.com. Comments? Write to us at [email protected].