Near-infrared light therapy shows improvement in mTBI recovery in a rat model (11/14/24 Newsletter)
This week’s lead article, Near-infrared light therapy shows improvement in mTBI recovery in a rat model, is in the Therapies & Diagnostic Tools Under Research category.
In this newsletter: Opportunities, Sports, Pathophysiology, Diagnostics, Therapies & Diagnostic Tools Under Research, and Youth.
We appreciate the Concussion Alliance volunteers and staff who created this edition:
Writers: Ella Webster, Josh Wu, Runa Katayama, Joey Peters, and Malayka Gormally.
Editors: Malayka Gormally and Conor Gormally
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Opportunities
Friday, November 15, 8 am PST: A free webinar, The Relationship Between Cognitive-Linguistic Performance and Sleep and Anxiety in Young Adults with Mild Traumatic Brain Injury, presented by Rocío Norman, PhD CCC-SLP and hosted by the Center on Brain Injury Research and Training. Register in advance.
Tuesday, November 19, 6 pm EST: a free webinar, Drugs for Neuropsychiatric Symptoms of Concussion, presented by Dr. Abe Snaiderman (Neuropsychiatrist) and hosted by the Canadian Concussion Centre. Register in advance.
Wednesday, November 20, 4 pm EST: a free webinar, Traumatic Brain Injury and the Military, presented by the Concussion Legacy Foundation and the Boston University CTE Center. It includes a lived experience panel with veterans and caregivers, followed by an overview of related research and available resources. Register in advance.
Call for study participants: military veterans who have had concussions and/or a traumatic brain injury, including any injury to your head or neck that caused you to lose consciousness or feel dazed/confused/experience a gap in memory. Eligibility: it’s been at least one year since your military service, and you are willing to participate in a 4-5 hour study visit in EITHER New York City OR Seattle, Washington. A study visit will include a brief set of thinking tests, an interview with surveys, a blood draw, and an MRI scan.
Participants will receive a copy of their MRI scan and research visit summary, be compensated for their time participating in the study, and be given modest support for travel expenses (e.g., ground transportation to the study site) upon request. Participants are asked to consider brain donation at the end of life. Read our blog post for more information on the Late Effects of TBI (LETBI) study. If you are interested, please contact Julia Kirschenbaum at julia.kirschenbaum@mountsinai.org, call us at 212-241-5152, or sign up online.
In case you missed it. Recordings of two recommended recent webinars from the Canadian Concussion Center:
– Exercise Therapy for Concussion presented by Dr. Mark Bayley, video link, slide deck.
– Strategies for Mental Health presented by Dr. Lesly Ruttan, video link, slide deck.
Sports
Elite ice hockey players with a history of 3+ concussions experience a higher level of poor mental health symptoms
In a review article in Labroots, Annie Lennon summarizes a study showing that elite ice hockey athletes who have sustained three or more concussions had a significant increase in poor mental health symptoms and burnout compared to those with no concussion history. While studies suggest exercise can protect mental health, players at an elite athlete level experience mental health challenges at similar rates to those seen in the general public, suggesting they are not receiving the protective mental health benefits of exercise. The finding that a history of multiple concussions is a factor may help explain discrepancies in the research.
In this cross-sectional study published in BMC Sports Science, Medicine, and Rehabilitation, Mitchell J. Andersson et al. surveyed 648 Swedish ice hockey players from top men’s and women’s teams. Players reported their history of concussive events, as well as mental health symptoms like depression, anxiety, burnout, hazardous alcohol use, and problematic social media use. After accounting for other factors, researchers found that “elite players with 3 or more concussive events are 2.1 times more likely to experience depressive symptoms and 3.5 times more likely to develop burnout” in comparison to those without a history of concussion.
Aside from a link between concussions and mental health symptoms, the researchers found that, regardless of concussion history, both male and female elite ice hockey players experienced a higher prevalence of hazardous alcohol consumption compared to a sample of university-aged athletes on several Swedish national teams and to a sample of the general public in Sweden. While male hockey players didn’t report a higher occurrence of mental health symptoms, female athletes experienced burnout more often than the other athlete populations samples and the general public.
Although this study sheds light on the possible link between concussions and mental health in elite athletes, it also shows that, amongst elite ice hockey players, high rates of alcohol use and, among female players, burnout occur even without concussions. This finding could suggest that other factors may contribute to these athletes’ mental well-being and help explain discrepancies in research on exercise’s lack of protective effects for elite athletes. Researchers cautioned that the generalizability of the results may not correlate to different sports or lower levels of ice hockey.
Pathophysiology
In the Emergency Department, an eye dysfunction patient survey helps stratify patients at risk for persisting symptoms and hospital admission
A recent study published in the International Journal of Emergency Medicine found that using oculomotor testing in the Emergency Department could help identify which mild traumatic brain injury (mTBI) patients are at higher risk for persisting symptoms. People visiting Emergency Departments (EDs) for an mTBI is increasingly common, spurring the need for new ED assessment tools. Ganti et al. used a patient survey tool to assess convergence insufficiency (CI), a condition where the eyes struggle to focus together on close objects, creating symptoms like double vision, headaches, and difficulty concentrating. The authors note that prior studies have found that CI is still present in up to 45% of mTBIs at 3 years post-injury and that CI was “associated with cognitive disturbances” and difficulty returning to work.
The study involved 116 adult patients who visited the ED within 24 hours of sustaining an mTBI and tracked them for 30 days following their diagnosis. Using the Convergence Insufficiency Symptom Survey (CISS)—a 15-question self-reported scale—the study authors assessed CI symptoms at participants’ initial evaluation. The researchers then correlated CISS scores with later outcomes, such as hospital admission for persisting symptoms, development of post-concussion syndrome (PCS), and rates of 30-day readmission for persisting symptoms. (Note: While PCS is a term still used by many researchers and clinicians, international consensus has shifted to using “persisting symptoms after concussion.”) They found that higher initial CISS scores were associated with a greater likelihood of hospital admission, PCS at 30-day follow-up, and readmission within 30 days. Women, on average, had higher CISS scores than men, suggesting potential gender differences in CI symptom expression post-mTBI.
This study highlights the potential usefulness of CISS as a quick and effective tool for risk-stratifying mTBI patients. High CISS scores indicate a higher risk of adverse outcomes, making it helpful in identifying patients who may require closer follow-up or targeted treatments.
The current diagnostic for rating TBI severity, the Glasgow Coma Scale (GCS), underemphasizes the suffering of those whose TBI is classified as “mild.” Supplementing the GCS with better indicators of prognosis can help more accurately diagnose and treat mTBI. The authors conclude that CISS could enhance Emergency Department triage for mTBI patients, as well as help guide further research and targeted interventions for those at high risk of prolonged recovery or complications.
Convergence Insufficiency Symptom Survey from the study
Diagnostics
A new app helps people identify a likely concussion and gives recommendations for immediate care
We recommend downloading the newly redesigned SCORE 4 Brain Health app to your phone (Apple Store or Google Play). You never know when you will need to identify if someone you care about has sustained a concussion. This app walks you through a series of questions that help identify a likely concussion, and we find it more valuable than simply reading through a standard list of concussion symptoms. After the app determines if there is a likely concussion, you can download a report with your answers to bring to a healthcare provider. The app then provides excellent, up-to-date advice for immediate concussion care.
Score 4 Brain Health was created by the Safe Concussion Outcome Recovery & Education (SCORE) Program at Children’s National Hospital and the Matthew Gfeller Center at UNC-Chapel Hill. The app also has resources on how to manage concussion recovery.
While the diagnostic and concussion management sections are for any age group, the app also has resources specific to parents and coaches. An article in wtop news quotes SCORE Director Dr. Gerard Gioia about the app’s resources for parents: “There’s a set of three questions that relate to the league’s policy,” Gioia said. “Is there a concussion protocol and guideline? How are parents informed about a suspected concussion? And tell us about your return to play protocol, and what documentation do you require after a youngster is supposedly ready to return?”
Therapies & Diagnostic Tools Under Research
Near-infrared light therapy shows improvement in mTBI recovery in a rat model
A press release from the University of Birmingham highlighted a new study that found near-infrared light therapy delivered transcranially through the skull can help repair tissue and potentially reduce secondary damage (such as inflammation) after mTBI. The study, published in Bioengineering & Translational Medicine, notes that complex inflammatory changes and increased programmed cell death (apoptosis) in the brain occur after the initial trauma. These secondary processes can worsen the outcome for mTBI patients. Targeted light therapy, called photobiomodulation (PBM), may provide protection against these secondary processes and “stimulate faster and better recovery for patients.”
Using rat animal models given mTBIs, scientists at the University of Birmingham compared a control group given sham treatments to an intervention group given daily two-minute bursts of near-infrared light of 660 nm or 810 nm delivered by a laser for three days post-injury. Andrew R. Stevens et al. found that the treatment group, particularly those given 810 nm light therapy, showed reduced markers of inflammation and apoptosis and improved memory and balance in behavioral tests after four weeks. This experimental method could “result in a new treatment option in an area of medicine that currently has few, if any, treatment options.”
Adult rats were randomized into a control group given sham treatments or into the treatment group with photobiomodulation after mTBI injury. For the treatment group, daily two-minute bursts of near-infrared light of 660 nm and 810 nm, or combined 660/810 nm, were delivered by a laser for three days post-injury. The researchers administered two standard behavioral tests. The novel object recognition (NOR) test assessed the rats’ spatial memory and exploratory behavior, indicating cognitive function; they were given the NOR weekly for 4 weeks. The beam walking (BW) test assessed the balance and recovery of motor functions (the voluntary control of movement patterns); the BW test was given every 8 days over the course of 4 weeks. Stevens et al. found that PBM at all wavelengths improved NOR and beam balance performance––demonstrating significant improvement in cognitive performance––and was associated with faster recovery, with the light wavelength 810 nm providing the “superior outcome.”
After the behavioral tests, the researchers studied the rats’ brain tissue using histology (microscopic examination of stained tissue slices) and immunohistochemistry to evaluate the degree of damage from the rats’ mTBI. The treatment intervention rats showed a significant reduction in the activation of astrocytes and microglial cells, which are implicated in “inflammatory processes in the brain that follow head trauma.” They also found a “significant reduction in biochemical markers of cell death [apoptosis]” in the intervention group.
The research on PBM continues to evolve as evidence shows promising results for recovery of mTBI. Because this method was only tested on male rats, further studies are needed to test the effect on females and human subjects. Professor Ahmed, who led the study, said, “We want to develop this method into a medical device that can be used to enhance recovery for patients with traumatic brain or spinal cord injury, with the aim of improving outcomes for patients.”
Youth
Risk factors and treatment of post-traumatic headache from concussion in youth
A systematic review of the literature on post-traumatic headache published in Headache: The Journal of Head and Face Pain found that female sex, number of acute concussion symptoms, and adolescent age were associated with prolonged recovery from concussion and persistent post-traumatic headache (PTH). Social determinants of health were also significant factors in PTH. Carlyn Patterson Gentile et al. created a synthesis of 33 studies further interpreted by expert youth PTH providers affiliated with the American Headache Society. With no definitive guidelines for managing PTH, the authors aimed to create a roadmap for tailored treatment of youth with PTH. Treatment strategies reviewed included pharmacological interventions, neuro-modulatory devices (such as transcranial direct current stimulation), physical therapy, physical activity, and behavioral health services.
Headache is the most common symptom affecting youth following a concussion (mild traumatic brain injury); one in five youth in the United States is diagnosed with post-traumatic headache following a concussion; 8% continue to have a headache longer than three months after their concussion. Several risk factors were found to be associated with prolonged PTH (PPTH), including female sex, adolescent age compared with adult or child, and a higher number of presenting symptoms at the time of injury. Many studies also found that either a personal history or a family history of migraine was also correlated with prolonged recovery. Prolonged recovery and PPTH may be more likely with a mild TBI versus more moderate to severe TBIs, especially in adolescents. Preexisting mood disorders may also be associated with prolonged recovery; comorbid anxiety and depression are frequently evident with recurrent headaches. Health disparities and inequities such as access to care, experience and interactions with the healthcare system, diagnosis, and treatments offered have also been identified as risk factors. Finally, disadvantaged racial groups have been associated with persistent concussion symptoms, with many athletes in this group experiencing reduced access to school and community resources.
The study goes into treatment options in depth. For pharmacological management, “expert consensus is that PTH in youth should be treated based on the primary headache disorder it most resembles.” For example, if the PTH resembles a migraine, then migraine therapeutics should be utilized. With regard to acute medication management of PTH, oral and intravenous analgesics (painkillers) play a primary role. Due to limited research and mixed results, pharmacological therapeutics are particularly challenging for treating PTH in youth. Most research has reviewed the use of standard migraine treatments, including tricyclic antidepressants, anti-seizure medications, anti-hypertensive medications, calcitonin gene-related peptide-targeted therapies, and supplements. The use of procedures and devices such as nerve blocks, acupuncture, and neuro-modulatory devices offer promise, but the review recommends further study. Similarly, non-pharmacological management, such as physical therapy, physical activity, and behavioral health, shows efficacy, but more studies are recommended.
While noting that future research is recommended to assist in developing best practices for treating PTH in concussed youth, the review is intended to serve as an initial compass for developing guidelines for managing youth with PTH. Limitations in protocols for the treatment of PTH in youth clearly exist; however, advances in the identification of risk factors for prolonged recovery and PPTH are evident. Future research is necessary in all domains of PTH care in children, with an emphasis on “high-quality prospective cohort studies” and standardization of data collection to ensure reliability and validity across studies. Continued research is also necessary to determine the underlying pathophysiology of PTH to help develop new treatment approaches.