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Monday, July 25, 2016

Aedes mosquito.jpeg

​Credit: iSTOCKPHOTO/A_TEEN

BY FRAN KRITZ

The US Federal Trade Commission (FTC) recently slapped a $300,000 fine on a company that makes a bracelet soaked in mint oil that claims to protect wearers from the Aedes mosquito, the insect that transmits the Zika virus.

Viatek, the company that makes the bracelet, said the device could protect wearers from mosquito bites for up to 120 hours, but the FTC found no scientific support for that claim. "With mosquito-borne illnesses in the news, consumers might be looking for products that protect them from mosquitoes," says Jessica Rich, director of the FTC's Bureau of Consumer Protection. "The [Viatek Company] took advantage of those concerns."

Fear Spurs Sales

Worries about the Zika virus are justified. Public health experts at the US Centers for Disease Control and Prevention (CDC) say many states in the United States are at risk of an outbreak. As of mid-July, no cases transmitted via a mosquito bite in this country had been reported. But at press time, the CDC was investigating a Zika case in Florida that did not involve travel to another country. The virus can also be transmitted through sex and transfer of other body fluids.

Although Zika is generally a mild illness, it has been linked to serious neurologic conditions including microcephaly, a birth defect that results in babies with very small heads and possible brain damage, and Guillain-Barré syndrome, which can cause temporary paralysis and, in rare cases, death.

"The neurologic threat caused by Zika is real, and people should be aware of it if mosquitoes carrying the virus make their way to their cities and towns," says David Taragin, MD, a neurologist with The Neurology Center in Silver Spring, MD. The consumer protection office in Montgomery County, MD, where Dr. Taragin lives and works recently sent out postcards to residents and posted information on their blog about avoiding Zika-related cons, including a warning from the US Securities and Exchange Commission about an increase in scams as companies rush to develop products or services to combat the Zika virus.

Consider only CDC and EPA-approved Products

Very few of the products that claim to protect against the Zika virus, including ultrasound wave devices and vitamins and supplements that repel mosquitoes, have been shown to be safe and effective, says Joseph Conlon, a technical advisor to the American Mosquito Control Association, a nonprofit information group in Laurel, NJ.

Instead, consumers should consider only products containing ingredients that have been recommended by the CDC and registered by the US Environmental Protection Agency (EPA), says Daniel Pastula, MD, MHS, assistant professor of neurology at the University of Colorado, Denver, and an expert in viruses transmitted by mosquitoes, ticks, and sand flies.

To find those products, visit the EPA's insect repellent site at bit.ly/EPA-InsectRepellent. Active ingredients approved for combatting the Aedes mosquito include DEET, picaridin, IR3535, oil of lemon eucalyptus, or para-menthane-diol. "CDC-recommended ingredients have been proven to repel mosquitoes and prevent mosquito bites," says Dr. Pastula. "Using products not backed by evidence can make people think they're protected, when we're not really sure they are."

All EPA-registered repellents have been evaluated and approved for effectiveness. When used as directed, they are considered safe and effective, even for women who are pregnant or breastfeeding.

Remove Standing Water

Mosquito spraying, which many communities plan to institute to help get rid of any Aedes mosquitos, is only partially effective, says Conlon. What may be more effective, according to the CDC, is to remove standing water, which attracts mosquitoes, both indoors (such as in vases containing flowers past their prime and in water bowls left to stand for pets) and outdoors.

Be Proactive

Zika is not the only virus transmitted by mosquitoes, says Dr. Pastula. In the US and its territories, West Nile, dengue, and chikungunya viruses may also be a threat. "Using evidence-backed products is the best protection you can give yourself." To be even safer, follow these recommendations.

1. Wear long-sleeved shirts and long pants when mosquitoes are out and biting.

2. Stay in places that have air conditioning and screens on windows and doors to keep mosquitoes out.

3. Sleep under a mosquito net if you are overseas or outside and unable to protect yourself from mosquito bites.


Thursday, July 21, 2016

Sound body balance.jpeg

BY SARAH OWENS

Certain aspects of physical fitness, including poor balance and a weak grip, are associated with a higher risk of dementia in people over the age of 90, according to new research published in the July 5 issue of the Journal of the American Geriatrics Society.

Testing Physical Health

The population of the so-called "oldest-old" (people older than 90) is projected to quadruple by the year 2050. Given that this group has the highest incidence of dementia, it's important to identify risk factors and ways to treat or prevent the disease. With that in mind, researchers at the University of California at Irvine analyzed 176 men and 402 women participating in The 90+ Study, an ongoing, population-based study of aging and dementia among people aged 90 and older. At the beginning of the study, 54 percent of participants were cognitively normal, while 46 percent had cognitive impairment. None had dementia.

At the start of the study and for at least one follow-up visit, participants performed physical tests, including a 4-minute timed walk; five chair stands; balancing for 10 seconds; and grip strength exercises. Performance on each test was measured on a scale from 0 (unable to perform) to 4 (best performance).

Evaluating Cognitive Function

Researchers also measured cognitive health at the start of the study and every six months afterward for an average of two and a half years. During each evaluation, researchers administered questions from a variety of standardized tests to measure memory, orientation, language, calculation, abstract thinking, and judgment—and to determine if, and when, participants developed dementia.

Identifying the Body-Mind Link

At the end of the follow-up period, 36.7 percent of participants had developed dementia. When looking at the scores on the physical tests, the researchers found that standing balance was associated most strongly with cognitive health, followed by performance on the 4-minute walk and grip strength tests.  They also noted that poor physical performance was typically detected two to three years before dementia, which was consistent with previous findings from The 90+ Study, and supported their hypothesis that declining physical performance "may be an early sign of late-age dementia."

Making Physical Testing Routine

The study's results may encourage doctors to use tests of strength and balance to screen their older patients for dementia risk, researchers noted. The simplicity and accessibility of the tests suggest that such screening would be both useful and feasible, they added.


Monday, July 18, 2016

Poor sleep.jpg

Credit: iSTOCK/Anthony Wing Kosner

BY FRAN KRITZ

People who have had a traumatic brain injury (TBI) may experience sleep problems a year and a half after the injury—and they may not even be aware of it, according to a study in the April 27, 2016 online edition and May 24, 2016 print edition of Neurology. "We found that the majority of those with TBI, no matter how severe, had long-term sleep disturbances but didn't realize it," says Lukas Imbach, MD, MS, a senior physician and neurologist at the University Hospital Zurich in Switzerland and lead author on the study, which was funded by the Swiss National Science Foundation and the University of Zurich.

Study Parameters

For 18 months, Dr. Imbach and colleagues followed 31 people who had sustained a TBI, with injuries ranging from mild to severe, as well as a control group of 42 healthy people. In addition to being asked about sleep behavior and daytime sleepiness, participants wore a device on their wrist for two weeks that measured body movement. They also spent a night in a video sleep lab where their brain and muscle activity, eye movements, and heart rhythm were monitored. To test for excessive daytime sleepiness, researchers measured how fast participants fell asleep in a quiet environment during the day.

Study Results

Sixty-seven percent of those with TBI experienced excessive daytime sleepiness compared with 19 percent of those in the control group, the researchers found. When asked how sleepy they were during the day, those with TBI didn't report feeling any sleepier than people in the control group. The study also demonstrated that people with mild TBI were just as likely to have sleep problems as those with severe TBI, and that these sleep problems persisted even though people with TBI slept an average of eight hours a night, compared to the control group, which slept an average of seven. The researchers didn't find any other health problems that could account for the sleep problems.

Search for Clues

During an acute phase after a TBI, patients sleep more and have deeper sleep, says Dr. Imbach. "We assumed the increased need for sleep was linked to a mechanism in the brain to help recovery. But the persistent sleepiness problem has a different mechanism. If it were only an acute effect it would not continue for a year and a half," he says. One possibility might be permanent damage to the brainstem in sleep-promoting centers of the brain. "If the hypothesis is true, we should see that on magnetic resonance imaging (MRI) scans," he says. "We have collected a lot of MRIs and are about to start analyzing the data."

Treatment option

The Swiss research team conducted a small study on a potential treatment—modafinil (Provigil), a wakefulness medication used for narcolepsy—for excessive sleepiness, and reported a 30 to 40 percent reduction in sleepiness. Modafinil reduced daytime sleepiness in this smaller study, but currently no specific treatment exists that addresses the need for increased sleep after TBI, says Dr. Imbach.

Concerning Consequences

People with TBI who are excessively sleepy during the day may be a greater risk for getting into car accidents or other public safety hazards, so they and their doctors should be monitoring for it," says Dr. Imbach, who considers the sleep-wake disorder a "silent epidemic." Further study is needed before guidelines are changed or new recommendations are made, he says. 


Thursday, July 14, 2016


​Credit: iSTOCKPHOTO/MONKEYBUSINESSIMAGES

BY FRAN KRITZ

Middle-aged blacks are four times more likely to die of a stroke than whites of the same age, according to a study published in the June issue of Stroke. Researchers wondered if inferior post-stroke care for blacks might account for the disparity, but the study, funded by the National Institute of Neurological Disorders and Stroke (NINDS), found the difference might be attributed more to the increased number of strokes among middle-aged blacks.

Measuring Risk Factors

Researchers analyzed data on almost 30,000 people selected at random from across the United States. Between 2003 and 2007, study participants completed a telephone interview and an in-home physical exam that assessed blood pressure levels and other stroke risk factors. The researchers reviewed the medical records for stroke diagnoses, and contacted participants every six months to ask about stroke symptoms, hospitalizations, and general health.

The researchers followed the participants for an average of nearly seven years. During that time there were 1,168 strokes, 242 of which were fatal.

Analyzing Results

When the research team looked at stroke incidence by age, they found that between ages 45 and 54, more blacks had a fatal stroke. Blacks also had more stroke risk factors, such as high blood pressure (71 percent versus 51 percent of whites) and diabetes (31 percent versus 16 percent). The risk of dying was four times greater for middle-aged blacks than for whites, but there was no difference in death rates between blacks and whites who survive a stroke.

Preventing Stroke

The way to reduce the disparity in incidence and mortality is to redouble efforts to prevent stroke, especially by controlling and preventing high blood pressure and diabetes, both of which affect blacks disproportionately, said the study authors. "We need to do more to focus on prevention and control of risk factors before they result in a stroke," said George Howard, DrPH, professor of biostatistics at the University of Alabama at Birmingham School of Public Health and lead author of the study.

Prevention is especially important because hypertension can impact blacks more severely than whites, said Walter Koroshetz, MD, FAAN, the director of NINDS. "The prevalence of hypertension is higher in blacks, but its impact is even greater in the black population," he said. "An increase of 10 mm Hg in blood pressure is associated with an 8 percent increase in stroke risk among whites but a 24 percent increase in stroke risk in blacks."

Researching Disparity

The NINDS is funding several health disparity trials through its Stroke Prevention Intervention Research Program (SPIRP) as well as education and training programs that target high blood pressure control in minority communities, according to Salina Waddy, MD, program director at NINDS.

Other studies are looking at ways to improve blood pressure control, including home blood pressure telemonitoring, patient education, visits to homes from community health workers, and mobile health technology. 


Monday, July 11, 2016

Credit: Sira Anamwong

BY SARAH OWENS

When it comes to how work environments affect brain health, the news is mixed. On the one hand, dealing with complex problems at work can benefit cognitive health, but a dangerous, fast-paced, or divisive work environment may take a toll on the brain, according to a new study published on June 16 in the Journal of Occupational and Environmental Medicine.

Occupational Factors that Affect Cognition

The researchers assessed workplace characteristics using the Occupational Information Network, or O*NET, which covers 974 occupations, to identify physical and psychosocial factors they suspected would affect cognitive health. These factors included physical hazards, how hard the job is and how fast it has to be performed, how often employees are required to solve complex problems, and whether there is conflict with coworkers or customers.

They hypothesized that occupations that require employees to work long hours, deal with unpleasant customers, or endure distracting noises and lights might negatively affect employees' cognitive function. They also wanted to test whether occupations that require solving complex problems might benefit employees' cognitive function.

Assessing Occupation and Cognitive Function

To test their theories, the researchers analyzed data about cognition and occupation from the Midlife in the United States (MIDUS) study, a national longitudinal study, funded by the National Institute on Aging, of the health and well-being of middle-aged adults in the United States.

They identified the occupations of 4,186 adults ranging in age from 32 to 81 and matched their occupations to related workplace hazards using information from the O*NET. Then they assessed the participants' cognition over the telephone using tests of word recall, verbal fluency, and inductive reasoning. The tests were designed to measure executive function (the ability to concentrate, remember events, and juggle tasks); episodic memory, or the personal memory of past events; and self-perceived memory, or how people perceive their own ability to remember.

The Brain-Occupation Link

After matching participants' occupations with their results on cognitive function tests, the researchers, led by Joseph Grzywacz, PhD, chair of the department of Family and Child Science at Florida State University in Tallahassee, found that all factors they examined—including the pace of work, job complexity, and workplace conflict—affected "nearly every indicator of cognitive function." Workers who had to solve complex problems as part of their job performed better in all three cognitive domains (executive functioning, episodic memory, and self-perceived memory).

Occupations that had a high degree of conflict, required employees to work long hours, or had lots of physical hazards negatively affected employees' cognitive health, particularly in the areas of executive functioning and episodic memory.

Age- and Sex-Related Differences

When the researchers analyzed the data further they found that the executive function of older workers was more affected by conflict, and that for women, solving complex problems benefited both episodic memory and executive functioning.

Conclusions

The results indicate that exposure to certain occupational factors may explain differences in cognitive aging, the researchers said. If doctors or caregivers notice signs of cognitive decline in a patient, friend, or family member, they may look to the workplace for an explanation.

Managers, bosses, and others in charge at work have a responsibility to maintain a clean, safe workplace, suggested Dr.  Grzywacz in a press release. "Designing jobs to ensure that all workers have some decision-making ability may protect cognitive function later in life, but it's also about cleaning up the workplace."