Read the most current news on neurologic diseases here! And we want your input. Leave your comments at the end of each article.
Monday, July 20, 2015
BY REBECCA HISCOTT
Not all children and teens with traumatic brain injury (TBI) recover at the same rate, and the severity of the blow is not always to blame. Another possible culprit is damage to the myelin and white matter in the brain, according to investigators at the University of California, Los Angeles (UCLA), who documented their findings in the July 15 issue of the Journal of Neuroscience.
Testing a Hunch about Myelin
“The brain’s nerve fibers [called axons] are encased in a fatty tissue called myelin that protects signals as they travel across the brain,” explained Christopher C. Giza, MD, director of the UCLA Steve Tisch BrainSPORT Program and a professor of pediatrics and neurosurgery at UCLA’s David Geffen School of Medicine and Mattel Children’s Hospital, in a news release. “We suspected that trauma was damaging the myelin and slowing the brain’s ability to translate information, interfering with patients’ capacity to learn.”
So he and his colleagues administered a series of computerized mental tasks to 32 kids and teens aged eight to 19 who had experienced a moderate to severe TBI within the last five months. The tests measured the brain’s information processing speed, as well as short-term memory, verbal learning, and cognitive flexibility.
They then used brain imaging to see how quickly the axons were able to transmit information across brain hemispheres. They also looked for evidence of damage to the white matter of the corpus callosum, which helps transmit signals from one part of the brain to another. They compared the results with those of a control group of 31 healthy, age-matched kids and teens.
Myelin Damage Equals Lower Cognitive Scores
Dr. Giza and his colleagues found that 16 patients in the TBI group showed signs of damage to the myelin of axons in the corpus callosum. These patients also had more signs of damage to the white matter and 14 percent lower scores on cognitive testing, and their brains transmitted information three times more slowly.
The remaining 16 patients with TBI had less or no damage to myelin, and their information transfer times were comparable to the healthy control children. They performed 8.5 percent better on cognitive tests than the TBI patients with myelin damage, but not as well as the healthy kids, who performed 4 percent better still.
Brain Imaging May Predict Risk
Dr. Giza and his colleagues suggested that this myelin damage, as seen on brain imaging, may help doctors identify people at risk of persistent TBI symptoms like headaches, fatigue, dizziness, moodiness, and difficulty concentrating. These patients may also need more follow-up than kids without myelin damage.
In future research, Dr. Giza said he and his team plan to look at how these biological markers change within the first year after injury, when patients with persistent symptoms begin to regain some of their cognitive function.
Look for a feature on sports-related traumatic brain injury (concussion) in the August/September issue of Neurology Now. To learn more about the signs and symptoms of TBI, see Traumatic Brain Injury: The Basics, and read about the latest TBI research by browsing our past articles.
Image by Alejandro Zorrilal Cruz [public domain], via Wikimedia Commons.
Friday, July 17, 2015
BY REBECCA HISCOTT
If you battle chronic pain, depression, or post-traumatic stress disorder (PTSD), you’ve probably had your share of sleepless nights. Maybe you’ve even sought treatment for it from your doctor.
If so, you may be familiar with cognitive behavioral therapy (CBT), a commonly “prescribed” non-drug treatment for insomnia. Approved by the American Academy of Sleep Medicine, this form of CBT teaches healthy sleep habits (going to bed and waking up at the same time each day; avoiding screens and stimulants like caffeine in the hour or so before bedtime; keeping the bedroom dark and cool), relaxation techniques, and how to counter negative thoughts and attitudes about sleep through talk therapy.
Now, a new study in the journal JAMA Internal Medicine shows that CBT for insomnia is not only extremely effective—as effective, or more effective, than sleep drugs, in fact—it can also help relieve the symptoms of sleep-disrupting conditions like chronic pain. That’s good news for patients who are starved for sleep and symptom relief.
Evidence Says CBT Improves Insomnia
Researchers reviewed 37 previously published trials involving 2,189 patients with insomnia and a co-occurring illness like depression, PTSD, chronic pain, cancer, fibromyalgia, or alcohol dependence. First, they looked at whether CBT was effective at treating the insomnia. The review revealed that patients who received CBT spent 12 percent more of their time asleep in bed, fell asleep 25 minutes faster after getting into bed, and had 45 minutes less time awake during the night than people who didn’t get the therapy and who were counseled about sleep habits or received a placebo pill, drugs, or another type of sleep aid instead.
Across the studies, about 36 percent of those receiving CBT no longer qualified as insomniacs on scales such as the Insomnia Severity Index, a short questionnaire evaluating sleep patterns. By comparison, only 17 percent of those who took a placebo or participated in alternative sleep therapies no longer had insomnia. And the benefits of CBT lasted up to 12 months in the longest trials.
CBT Helps with Pain, Fatigue, and Depression
The researchers also observed small improvements in medical or psychiatric symptoms in the people receiving CBT compared with those in the control groups. For instance, people with chronic pain reported lower levels of pain, those with depression or PTSD reported fewer symptoms, and women with breast cancer reported less fatigue.
In general, the gains were more pronounced for psychiatric conditions like PTSD or depression than for medical conditions like cancer or fibromyalgia—possibly because insomnia takes a greater toll on cognitive and emotional symptoms like mood and anxiety, the researchers suggested. Patients receiving CBT also reported improvements in overall mood and daily functioning.
Talk to Your Doctor
If chronic pain or another medical condition has you hopelessly counting sheep, CBT could be your ticket to a good night’s rest—with the added benefit of taking the edge off your other symptoms.
For more information about cultivating healthy sleep habits and managing chronic pain, see The Waiting Room in the August/September issue of Neurology Now. To learn more about sleep disorders, browse our archives here.
Image by Nojavon (own work) [CC BY-SA 3.0], via Wikimedia Commons.
Tuesday, July 14, 2015
BY ALEX CATALAN
As more states (23 and counting) legalize marijuana for medicinal purposes, patients and advocates have been encouraged by studies suggesting it may be effective for treating neurologic symptoms like chronic pain, sleep disorders, and muscle spasms in multiple sclerosis (MS). But a new review of the existing research published in the Journal of the American Medical Association (JAMA) warns that the evidence to date is not rigorous enough to support its benefits.
Benefits the Analysis Revealed
The researchers looked at 79 studies involving 6,462 participants who were treated with medical marijuana for symptoms such as chronic pain, spasticity due to MS, depression, anxiety, sleep disorders, nausea and vomiting from chemo, appetite loss due to HIV/AIDS, and glaucoma. They then rated the quality of the evidence in each of these studies in terms of bias, judging that at least 70 percent were at high risk for having biased results.
They found that people with chronic pain who were treated with cannabinoids had a 30 percent or greater reduction in pain compared with those taking a placebo. The evidence also suggested that medical marijuana may improve muscle spasticity in MS patients, but these results were not statistically significant.
Cannabinoids were also linked to modest improvements in nausea and vomiting due to chemo, more weight gain in patients with HIV/AIDS, and improvements in tic severity in people with Tourette syndrome, but these were considered low-quality studies. Medical marijuana also appeared to improve symptoms of anxiety.
Analysis Revealed Short-Term Side Effects
Cannabinoids were associated with a slew of side effects, the researchers warned. Among them were changes in short-term memory, a distorted perception of time, trouble with depth perception and problem-solving, and shortened attention span—all symptoms of the “high” that goes along with the drug’s psychoactive component, tetrahydrocannabinol, or THC. The drug can also produce short-term symptoms of withdrawal, the authors said.
But, they added, there was no evidence that cannabinoids were linked to any long-term adverse events.
Epilepsy Studies Were Not Included
Some reports have suggested that cannabinoids may be helpful in reducing seizure frequency in children with severe genetic epilepsy syndromes. For example, one study from New York University and the University of California, San Francisco, treated 23 children with Dravet syndrome—a rare and severe form of childhood epilepsy—with an oral cannabis abstract. After three months of treatment, 39 percent of the children had 50 percent fewer seizures.
But large studies of medical marijuana for severe genetic forms of epilepsy are scarce, in part because these conditions are so rare. See the Neurology Now article “Weed Backers” to learn more about medical marijuana for childhood epilepsy.
Authors Call for More High-Quality Research
Medical marijuana may help treat depression, sleep and anxiety disorders, glaucoma, HIV/AIDS, and Tourette syndrome, but much more research is needed, the study authors wrote. And the drug itself, and its various strains, remain poorly understood. There is a need to investigate its health effects and possible harmful side effects more generally, they said.
The American Academy of Neurology offers resources for patients and families who want to learn more about medical marijuana and guidance on what the evidence says about their use in various neurologic conditions. Read their guidelines here. To learn more about research on medical marijuana for neurologic conditions, browse our archives here.
Image via eggrole on Flickr.
Friday, July 10, 2015
BY ALEX CATALAN
Here’s a good reason to let your kids swing from trees and play in the dirt: Elementary school students who were exposed to more nature and vegetation tended to perform better on cognitive tests, according to a new study published in the Proceedings of the National Academy of Sciences.
Past research has shown a link between exposure to green spaces and better mental health and lower levels of anxiety and depression. Studies have also shown that taking nature walks or looking at images of natural sites can enhance adults’ attention spans, but this is the first study to test the association with better cognitive development, the authors said.
Being Around Greenery Boosts Memory Performance
Conducted between 2012 and 2013 in Barcelona, Spain, the study involved 2,623 children from 36 schools who were given memory tests at the beginning of the year and then once every three months for the remainder of the year. The researchers categorized children based on how much green space surrounded their homes, commutes, and school grounds. Based on this data, they created a total score for how much greenery the students encountered every day.
Children exposed to more greenery had higher scores on tests of working memory than kids who spent less time around nature. By the final test, children who encountered more greenery scored 15 points higher than those who encountered less.
The authors noted that the positive effects of being around greenery may be enhanced, in part, by decreased exposure to air and noise pollution, factors that have been associated with poorer cognitive development and outcomes.
Future research, they said, should focus on the effect of green spaces on preschool children as well, and even potentially on how maternal exposure to nature affects prenatal development.
More Green Spaces Could Help Underperforming Kids
Creating more green spaces around schools would improve cognitive performance in around 8.8 percent of children who currently have low scores on tests of working memory, the authors said.
For almost half the world’s population, which is exposed to fewer nature sites and more air and noise pollutants, the authors said, planning for more green spaces could improve the lives (and thinking skills) of future generations.
For more coverage of factors that impact children’s cognitive performance, browse our archives here.
Image via Tom Woodward on Flickr.
Thursday, July 09, 2015
BY REBECCA HISCOTT
Post-traumatic stress disorder (PTSD) is twice as common in women as in men, yet most research has focused on the disorder’s effects in men, particularly veterans. A new study in the journal Circulation that focused on women only found that those who experienced a traumatic event like a natural disaster or a physical or sexual assault had a higher risk of suffering a stroke or heart attack, even if they didn’t develop PTSD. And those who did develop the disorder had the highest risk.
Researchers looked at rates of stroke and heart attacks in 49,978 women who were between the ages of 25 and 42 when they enrolled in the Nurses’ Health Study II in 1989. The women indicated whether they had experienced a traumatic event and reported on whether they had symptoms of PTSD such as flashbacks of the trauma, insomnia, fatigue, difficulties remembering or concentrating, nightmares, a heightened state of alertness and agitation, and feeling emotionally “numb.” They also provided information on lifestyle factors like smoking, obesity, diabetes, physical inactivity, and alcohol consumption.
PTSD and Trauma Increase Cardiovascular Risks
During the 20-year study period, there were 277 heart attacks and 271 strokes. The researchers found that women who had had a traumatic experience and had four or more symptoms of PTSD (16 percent of participants) had a 60 percent higher risk of stroke or heart attack than women who didn’t report a traumatic experience or PTSD symptoms (21 percent). Women with no symptoms of PTSD but who reported a traumatic experience (47 percent) had a 45 percent higher risk.
The 16 percent who reported a traumatic experience and three or fewer symptoms of PTSD did not have a higher risk for heart attack or stroke than women who had no PTSD or trauma, the researchers were surprised to find. They offered no explanation for this finding.
Unhealthy Habits Explain Part of the Link
Some of the association between PTSD symptoms, trauma, and cardiovascular events was explained by unhealthy habits such as smoking and inactivity, as well as physical conditions like obesity and high blood pressure—all of which independently increase the risk for stroke and heart attacks. Among women exposed to trauma but with no symptoms of PTSD, these lifestyle factors accounted for 14 percent of the association; among women with four or more PTSD symptom, these factors accounted for 47 percent.
A Direct Link between PTSD and Cardiovascular Events
Still, more than half of the heart attacks and strokes could not be accounted for by these lifestyle factors, suggesting a more direct link to PTSD. “PTSD is generally considered a psychological problem, but the take-home message from our findings is that it also has a profound impact on physical health, especially cardiovascular risk,” said lead author Jennifer Sumner, PhD, an epidemiology Merit fellow at the Mailman School of Public Health at Columbia University, in a news release.
It’s unclear how PTSD is associated with a higher risk of heart attack and stroke, but past research has suggested that the disorder is linked to dysfunction in the autonomic nervous system (which is responsible for functions like breathing, heart rate, and digestion), inflammation in brain, and the release of potentially harmful compounds like the “stress hormone” cortisol—all of which can increase the risk of heart attack or stroke. Future research should investigate these possible mechanisms, the researchers said.
Screening for PTSD and Cardiovascular Risk a Must
The study results, while limited to women under the age of 65, suggest that doctors should look for signs of trauma or PTSD in their female patients, and should encourage healthier habits, the study authors said. Cardiovascular disease is the leading cause of death among women, and it’s on the rise among middle-aged women in particular, they noted.
Heart-Healthy Steps to Take Today
These 4 strategies can help anyone reduce their cardiovascular risk:
1. Evaluate Your Diet. A poor diet can lead to obesity, high blood pressure, and high cholesterol, which can up your stroke risk. Avoid processed foods, moderate your alcohol intake, and fill your plate with fruits, vegetables, whole grains, and lean protein.
2. Break a Sweat. Moderate aerobic exercise such as walking, swimming, or cycling for 30 minutes each day can help insulate your brain against stroke, as well as Alzheimer’s disease and dementia.
3. Kick Butts. Studies have shown that smoking is the most significant lifestyle factor linked to stroke risk, so visit smokefree.gov for tips and strategies to help you quit.
4. Manage Medical Conditions. Get any other existing medical conditions under control, particularly those linked to heart health like high blood pressure or atrial fibrillation (irregular heartbeat). Make sure you’re taking the right medications and adopting healthy lifestyle habits, and talk to your doctor to learn what more you can be doing to manage your condition.
For more tips on preventing strokes, browse our archives here.
Image via 55Laney69 on Flickr.