Monthly Archives: September 2010
Defining the relationship between mild traumatic brain injury and postconcussion syndrome
It can be difficult to define mild traumatic brain injury (mTBI). Features such as age, sex, education, psychological history, or medical history can lead to differences in symptom reporting. The pathology of mTBI is unclear and can be different depending on the bio mechanics that caused the injury (accelerations/deceleration, direct blow, rotation). There is further difficulty in that symptoms can be quickly alleviated in some case, but persist for several months in other cases.
There is currently some disagreement on the definitions of mTBI and post-concussion syndrome (PCS), as well as what factors contribute to PCS and why. A recent paper offered the following definitions for clarification:
mTBI can be defined as “an essentially reversible syndrome without any detectable pathology,” in which symptoms can include headache, dizziness, nausea, unsteady gait, slurred speech, and poor concentration. Clinical indicators can include a GCS of 13 or higher and post-traumatic amnesia of no more than 24 hours.
PCS is the “constellation of symptoms in physical (eg fatigue, headaches), cognitive (eg difficulties with concentration and memory) and emotional (eg irritability, anxiety) domains that persist weeks, months, and even years after an mTBI.”
Williams WH, Potter S, & Ryland H. Mild traumatic brain injury and post-concussion syndrome: A neuropsychological perceptive. Journal of Neurology, Neurosurgery & Psychiatry. (September 2010).
Leisure activities after traumatic brain injury, Traumatic Brain Injury Attorneys
Leisure activities—such as reading, sports, outdoor activities, or other hobbies—are an important part of our day-to-day lives. Leisure activities can also contribute greatly to a recovery after TBI. Not only do such activities add opportunities for social interaction and physical health, they can also enhance a sense of independence and personal accomplishment for returning to an activity that was enjoyed before the injury.
A recent study looked at three aspects of leisure activities after TBI. One, how does participation in leisure activities change from before injury to one year after injury? Two, how do age and gender affect participation in leisure activities? Three, are people with TBI bothered about how well they can participate in leisure activities?
Their results found that, one year after injury, 81% of people with TBI were not participating in leisure activities at the same level they did before injury. The most popular new leisure activity after injury was watching television. These changes contributed to a more sedentary, less social life—which dissatisfied most participants. Although decreasing some leisure activities, such as partying or drug and alcohol use, were considered to be positive changes, participants felt there were few new activities that could replace the lost ones.
Wise EK, Mathews-Dalton C, Dikmen S, et al. Impact of traumatic brain injury on participation in leisure activities. Archives of Physical and Medical Rehabilitation. (September 2010).
Surrogate consent and advocacy for research participation in cases of severe brain injury
Currently, there is no established standard of care for brain injury patients in a vegetative or minimally conscious state. New technology, such as deep brain stimulation, may hold promise as a treatment, but research efforts for these technologies can be complicated and stunted by ethical considerations.
Monique Lanoix, an expert in medical ethics, has suggested two potential issues that decision-making surrogates face when deciding whether or not to consent their patient for research participation. One issue is that, without an established standard of care, patients may get at least some medical or rehabilitation treatment from the study. Another issue is that surrogates may interpret the study as optimal care and consent to research participation with hope for better services.
Researchers should therefore be aware of how these issues can shape the surrogate’s decision and focus on education and communication of their research protocol.
Lanoix M. Where angels fear to tread: Proxy consent and novel technologies. Brain Injury. (September 2010).
Physical activity is related to glucose intolerance in spinal cord injury patients
Poor glucose tolerance (a precursor for diabetes) is relatively common in people with spinal cord injury. Muscle, which is heavily involved in glucose disposal and transport, becomes atrophied after spinal cord injury—thus leaving less muscle tissue left to respond to glucose. Additionally, the reduced level of physical activity common after spinal cord injury increases fasting glucose.
A recent study of 25 spinal cord injury patients found that increased physical activity improves glucose tolerance—independent of size and area of injury. It is important to note that, although formal exercise improved glucose tolerance, non-exercise-related activity such as housework or errands also contributed to this improvement.
Raymond J, Harner AR, Temesi J, & van Kemenade C. Glucose tolerance and physical activity in people with spinal cord injury. Spinal Cord. (August 2010).
Why does spinal cord regeneration therapy that works for animals fail to work for humans?
Spinal cord injury patients and their families may have heard of research success in regenerating neural damage. However, most of this success has come from animal studies, and have not translated well in human studies.
A recent review of therapies for spinal cord injury discussed the reasons for this difference:
- In humans, the spinal cord injury extends over several sections of the spine. In animal studies, an injury is artificially created and often limited to one section.
- Animal studies usually use thoracic injury, but cervical injury is the most common injury in humans (lumbar is the second most common). The cervical and lumbar regions supply nerve fibers to arm and leg muscles.
- Animal studies focus on therapies for acute injuries, but these therapies do not translate when applied to chronic spinal cord injuries in humans.
Although animal studies provide an excellent model for understanding the mechanics of neural regeneration, these challenges need to be addressed before regeneration therapy can be useful to human patients.
Dietz V. Recent advances in spinal cord neurology. Journal of Neurology. (August 2010).
When “having your bell rung” really means “mild TBI”: Terminology matters in sport-related brain injury
Concussion, mild traumatic brain injury, and mild head injury are diagnostic terms that have traditionally been interchangeable. Clinicians argue that each diagnosis carries a distinct set of features (especially between mTBI and concussion), but in the meantime, the exact terminology describing impact to the head can lead to stereotyping and inaccurate expectation of symptoms and recovery. In a recent study that reflected a university athlete’s familiarity and understanding of terms, athletes thought that:
- The term “concussion” was the most familiar term, carried the least negative expectations, and was an injury that led to temporary, minor symptoms.
- The term “mild TBI” was the least familiar term, carried the most negative expectations, and was an injury that led to more serious, permanent symptoms—including depression and memory loss.
- The term “mild head injury” was considered the injury most related to contact sports, and was the only term associated with bleeding.
This imbalance of understanding and expectation not only reflected a lack of education on the part of the athletes, but also reflected a preference for terminology use on the field. For instance, using the term “concussion” instead of “brain injury” in order to keep spirits and recovery expectations high can discourage complete understanding of the injury, and potentially encourage ill-advised actions such as prematurely sending an athlete back to sport.
Weber M & Edwards MG. The effect of brain injury terminology on university athletes’ expected outcome from injury, familiarity and actual symptom report. Brain Injury. (September 2010).
Patterns in anoxic brain injury
Anoxic brain injury can result from anything that causes an inadequate supply of oxygen to the brain—carbon monoxide poisoning, respiratory arrest, or anemia, for instance. Certain parts of the brain are vulnerable to this decrease in oxygen, and these parts of the brain are responsible for functions such as memory, motor skills, and visual perception.
Anoxic brain injuries do not occur as frequently as traumatic brain injuries and therefore research is relatively limited. However, since there are certain brain areas thought to be vulnerable to anoxia, there should also be fairly clear clinical and functional patterns of impairment.
A recent study combining multi-causal cases of anoxic brain injury found that anoxic brain injury patients did indeed have poor scores in memory and visual perception (but not significantly in motor skills). As compared to traumatic brain injury patients, anoxic brain injury patients were more likely to acquire late onset seizures, have poorer scores in short-term and visual memory tasks, and show less progress in rehabilitation.
Fitzgerald A, Aditya H, Prior A, McNeill E, & Pentland B. Anoxic brain injury: Clinical patterns and functional outcomes. A study of 93 cases. Brain Injury. (September 2010).
Psychological distress and healthcare costs of pediatric mTBI
Although pediatric mTBI patients are not usually hospitalized, it is still expected that there will be some increase in TBI-related medical costs. Mild traumatic brain injuries are complex and outcomes can vary greatly—making a prediction of financial burden difficult to pinpoint. Past studies that have explored the financial burden of mTBI have been limited by variations in recovery time and complications due to cases of psychological distress.
Recovery from mTBI is still a controversial subject. There have been many reports of full recovery from mTBI within 3 months of injury. However, more recent studies have shown that some cognitive and behavioral symptoms can persist for years.
Psychological distress—as defined by clinical diagnoses such as depression or anxiety, psychotic mental disorders, hallucinations, hyperactivity, or substance abuse—can complicate the diagnosis and outcome of mTBI, regardless if the condition is pre-existing or post-injury.
A recent study published in Brain Injury specifically addressed these research limitations. Hospital records were investigated to look at a period of one year before injury in order to establish evidence of pre-existing psychological distress, and for three years after in order to determine new cases of psychological distress, as well as recovery time and outcome.
Their results were as follows:
- Injured children had approximately 75% greater medical costs than uninjured children.
- Injured children who showed evidence of psychological distress had nearly 3 times the medical costs of children who showed no evidence of psychological distress. These figures were controlled for pre-existing cases of psychological distress.
- One-third of the total medical costs occurred within 6 months of injury. More than half the total medical costs occurred within one year of injury.
It was not examined if mTBI had a direct link to new cases of psychological disorders, and it is possible that increased exposure to medical facilities increased new diagnoses of previously undiagnosed psychological disorders. After being controlled for recovery time and psychological distress, it remains that pediatric mTBI treatment is expensive and requires comprehensive, ongoing treatment for at least a year after injury.
Rockhill CM, Fann JR, Fan M-Y, Hollingworth W, & Katon WJ. Healthcare costs associated with mild traumatic brain injury and psychological distress in children and adolescents. Brain Injury. (July 2010).
Velcade is an effective treatment for TBI
Velcade (bortezomib) is a proteasome inhibitor that has been approved for use in certain cancers, and has been shown useful for other cardiovascular and inflammatory diseases.
One of the most dangerous results of traumatic brain injury is the inflammation that can occur directly after injury. As a proteasome inhibitor, Velcade has the potential to regulate such inflammatory responses, and may therefore be of benefit to survivors of traumatic brain injury.
In a recent animal study, Velcade (administered 2 hours after injury) was found to significantly decrease inflammation, lesion volume, and functional deficits. Although Velcade has the potential to be a useful treatment for traumatic brain injury, it will need further clinical study to determine dosage.
Qu C, Mahmood A, Ning R, et al. The treatment of traumatic brain injury with Velcade. Journal of Neurotrauma. (August 2010).
DHA supplements reduce diffuse axonal injury
Docosahexaenoic acid (DHA) is an omega-3 fatty acid that is commonly found in fish oil. Although the human body does not manufacture very much DHA naturally, a large percentage of our DHA is found in the white matter areas of our brains.
Diffuse axonal injury—which is a common injury in falls or car accidents—can twist, stretch, and shear the white matter tracts of the brain. DHA has therefore been of interest to scientists researching methods of reducing diffuse axonal injury damage.
In a preliminary animal study, algae-derived DHA was administered for 30 days after diffuse axonal injury. Researchers found a reduced amount of damage in animals that received supplementation that was significantly better than animals that did not receive supplementation. Further clinical studies are needed to determine dosage recommendations for humans (10mg or 40 mg doses were administered to the animals, equal to roughly 1-3 grams for humans). In the meantime, DHA is considered safe, easily accessible, and potentially beneficial to traumatic brain injury survivors.
Bailes JE & Mills JD. Docosahexaenoic acid (DHA) reduces traumatic axonal injury in a rodent head injury model. Journal of Neurotrauma. (August 2010).
