Associate professor Steven Howard, MD, is well known for his research on fatigue and sleep deprivation, especially as it relates to health-care professionals. Howard’s previous research has shown the benefit of napping on emergency room doctor and nurses’ performance, the implications of fatigue among clinicians and the potential risks of daytime sleepiness among resident physicians.
Below he discusses how fatigue negatively affects performance, the role cultural beliefs or societal pressures play in increasing the prevalence of sleep deprivation in our country and how organizations and professional societies can promote sleep as a priority among health-care professionals.
What happens, physiologically, when a person’s sleep balance is disturbed?
Individuals have a genetically determined sleep need, which for adults is around eight hours. Most of us get far less than this. If you get less sleep than needed, then you develop what is called a “sleep debt.” The only way to repay a sleep debt is by obtaining adequate sleep. People often don’t repay sleep debts for many reasons including that some believe sleep is just “lost time.” Individuals with a sleep debt will often have impaired performance and negative moods, and they are prone to falling asleep at work and elsewhere.
A mouse study published today in Molecular Psychiatry sheds light on how a particular version of a dopamine receptor in the brain (called D4) could play a role in an individual’s likelihood of developing Attention Deficit Hyperactivity Disorder. Dysfunction of this version of the D4 receptor has been associated with ADHD as well as other conditions characterized by disordered impulse control, including drug addiction. In the study, NIH Newsexplains:
…researchers inserted three variants of the dopamine D4 receptor into cells and into mice so that they could investigate differences in biological activities. The researchers found that the D4.7 variant, unlike its D4.2 and D4.4 counterparts, was not able to interact with the short version of the dopamine type 2 (D2S) receptor to reduce glutamate release in a brain region associated with impulsivity and symptoms of ADHD in humans.
Living with a chronic illness can be a hassle at best. And at its worst, chronic disease can leave patients feeling powerless and depressed as they face pain, fatigue, isolation, and an inability to do the things they could once do.
Now, according to an article in the AARP Bulletin, almost every U.S. state is offering workshops designed to empower the chronically ill and help patients deal with the unique challenges of building a new life around chronic illness. Originally developed at Stanford, personalized statewide programs like You Can! Live Well Virginia! help patients thrive despite their conditions. Services range from helping patients with medicine compliance to workshops on avoiding isolation via connection with others with similar experiences:
“People see that someone like them is living successfully with a chronic condition,” said April Holmes, coordinator of prevention programs for older adults in the Virginia Department for the Aging. “It can be inspirational.”
Although chronically ill patients spend more time than average in the hospital system, the majority of their time is still spent in the “real world.” Programs like Virginia’s are designed to complement generalized medical advice with community-based tools that patients can use to manage their everyday lives. Given that 8 out of 10 of all older Americans have a chronic disease, the benefits of helping these patients connect with and support one another are obvious.
Web-savvy physicians and e-patients aren’t the only ones harnessing the powers of new media for medical education. Famously bizarre musical artist Björk has just released a new song, “Virus,” as an interactive iPhone/iPad app. The appropriately named song describes what happens when a virus infects the body, and the app allows users to play along, altering the song accordingly. The video above reveals a sneak peek into the app, though each user’s experience will be different.
Human beings who react to a stimulus with movement (say, react to a hot stove by moving their hand) can’t do so instantaneously. Some neural processing must occur beforehand, accounting for the gap between the moment when a racecar driver hears “GO!” and the moment when his foot hits the gas pedal (the gap between “planning” and “execution” of movement). Historically, scientists who have theorized about what that neural processing looks like have come up with something resembling the current “rise-to-threshold” hypothesis:
Person anticipates “go” signal. The anticipation (“planning”) causes neurons to begin firing-not enough to cause movement, but enough to prep for it.
Person receives “go” signal (pain from hot stove, gunshot signifying beginning of race). Neurons fire like crazy, initiating motion (“execution”).
By this commonsensical reasoning, the more anticipatory neuron action goes on before the “go” signal, the quicker a person will move in response to that signal.
Stanford researchers led by Krishna Shenoy, PhD, and Maneesh Sahani, PhD, however, have now successfully used a new technology to monitor individual neurons’ activity in real-time, allowing them to take a much more in-depth look at reaction times. Their findings, which appear in Neuron, contradict the “rise-to-threshold” hypothesis, offering for the first time a look into why individuals’ reaction times vary.
According to the release, reaction time has little to do with how long the “planning” period lasts, and a lot to do with the trajectory of the neural activity in the brain. The concept is fairly simple: the closer the neurons that fire during planning are to the neurons that must fire to initiate execution, the shorter the reaction time. The Stanford team was able to create a highly accurate model of what the reaction of any arm motion would be based on the accompanying neural activity.
Shenoy and Sahani hope their findings will help improve existing “neural prostheses” - that is, moving pieces such as artificial limbs or computer cursors that could be manipulated by the brain. These devices would be extremely useful for amputees and paralytics.
The latest in genuinely cool gadgetry with serious medical potential: thin, pliable circuitry that can be applied directly to the skin. Researchers designed the electronic skin graft, which they’re calling “epidermal electronics,” to match skin’s mechanical properties: it’s thin, elastic, and tear resistant.
The device, which can be rubbed onto skin with water like a temporary tattoo, must still be subject to further research: the product’s breathability and sweat resistance have yet to be fully tested. However, the actual and potential medical uses are already enough to make any health blogger/gadget enthusiast clap her hands with excitement. Science Nowexplains:
In one experiment, the group applied a device the size of a postage stamp to a person’s chest to pick up the electrical signals produced by the heart. The measurements agreed “remarkably well” with those produced by a hospital electrocardiogram, the researchers say, without relying on potentially uncomfortable gels or tape. In another experiment, the group applied a device containing a microphone to a person’s throat and fed the signal to a computer. The computer could recognize four different words: “up,” “down,” “left,” and “right.” This technology could eventually help people with some disabilities control computers, the researchers say.
Researchers also expect the device to pave the way for future non-invasive sensors that would monitor brain activity or allow users to control computers remotely via subtle voice commands and movements.
Erin Prosser at Scientific American Blogswrites that consumers who debate the nutritional values of organic versus conventionally grown fruits and vegetables may be missing the point:
So for now, I say whether you choose the organic bag of apples or the conventionally grown ones really doesn’t make a big difference. As long as you’re choosing any bag of apples over a bag of Doritos, you’re on the right track.
Physicians should expect to see elevated blood pressure among patients in response to this week’s stock market swan dive, Houston’s Methodist Hospital is warning:
Kevin Lisman, MD, an arrhythmia specialist, says that while it’s hard to make a direct connection between market declines and heart trouble, he believes the association is “Very likely. People see their retirement funds falling.” Heart arrhythmias are associated with high blood pressure and sustained psychological stress or fatigue.
The release also predicts (perhaps not surprisingly) that economic turmoil will drive Americans to stress eating and sleep issues.
You may think medical apps and 3D tissue printing are pretty cool medical technologies, but these nano-robots are some stiff competition. These tiny robots can self-assemble and have serious medical potential: If they make it past the research phase, doctors might one day use them to transport treatments to highly specific places in the body, remove particles for study, and more. In this video, one little micro-robot shows off its super-strength by picking up and carrying a glass bead four times its weight.
Medical advances have transformed HIV infection from a certain death sentence to a potentially survivable (if still incurable) disease, and the result is a growing population of middle-aged AIDS patients. An article recently published in HealthyCaladdresses some of the new and unique challenges that this population faces.
For the first time in history, Herbert A. Sample writes, physicians are treating large numbers of older HIV-positive patients:
Data released by the federal Centers for Disease Control and Prevention in 2008 showed that almost 186,000 men and women age 55 and up were living with HIV. And the latest CDC statistics, released in 2006, found that at least 10 percent of new HIV infections nationwide, and 20.5 percent of new AIDS diagnoses, were among men age 50 or older. In 1982, only 7.5 percent of new AIDS diagnoses were 50 years old or older.
These patients may be living longer than past generations of HIV-positive people, but their lives are still significantly affected. HIV-positive patients tend to age much more rapidly than healthy people and suffer age-related issues like neurodegeneration and bone-density loss earlier. And:
Older patients who are stable but whose immune systems operate less than optimally face higher odds of contracting osteoporosis, or cardiovascular, kidney or liver problems, said Dr. Peter Ruane, a Los Angeles internist who treats HIV and AIDS patients. Those complications may be result from HIV, AIDS, the caustic medicines they took early on or even safer ones that have been developed over the last 15 years, he added.
The article also discusses a small, but still significant, group of patients who contracted the virus in their 50s as opposed to having lived with the disease for decades. Since the bulk of preventative efforts have focused on the 13- to 40-year-olds who comprise two thirds of the infected population, it’s possible that older adults simply do not have access to the same safe-sex information and guidelines. Rising sexual activity in seniors and a general “I’m-old-so-it-doesn’t-matter” attitude towards condom use are also listed as possible reasons for adults contracting HIV later in life.
