Does Evolution Explain Why Our Sleep Habits Change With Age?

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iStock

Laugh all you want now about Grandma's 8 p.m. bedtime; after reading this, you might just want to thank her. One team of researchers report that older adults' earlier body clocks may have evolved to ensure that at least one person was always awake to watch over a family group. They published their findings in the Proceedings of the Royal Society B.

Scientists believe that many groups of social animals take turns sleeping and standing guard. This sentinel hypothesis, as it's known, is easiest to observe in a line of sleeping ducks; the last duck in a row literally sleeps with one eye open. But we didn't know whether this phenomenon extended to humans.

To find out, researchers collaborated with Hadza people of northwestern Tanzania. Many Hadza maintain a hunter-gatherer lifestyle, working and sleeping far from the noise and light pollution of the cities. The researchers recruited a group of 33 adults between the ages of 20 and 60 and gave each person an actigraphic (movement-tracking) wristband. For 20 nights, the actigraphs recorded participants' tossing and turning, their waking, and their stillness in sleep.

The big-picture results looked a lot like you might expect. Average bed- and wake-up times were around 10 p.m. and 7 a.m., respectively. But those were just the averages. Within even this small group, two familiar chronotypes emerged: the older early birds, who bedded down around 8 p.m. and woke by 6 a.m., and the younger night owls, who were up past 11 p.m. and slept until 8 a.m.

Most compellingly, the researchers say, nobody ever slept through the night. Each person woke several times per sleep period, whether to pee, go for a smoke, soothe a crying baby, or just roll over in bed. The resulting gaps in sleep time meant that someone in the group was awake at almost all times. Out of 20 nights, there were only 18 minutes in which the entire group was sound asleep.

Co-author Charlie Nunn is an evolutionary anthropologist at Duke University. He says the group's early bird/night owl split, combined with the frequent mid-sleep awakenings, may be our bodies' way of keeping our families safe.

"If you're in a lighter stage of sleep, you'd be more attuned to any kind of threat in the environment," he said in a statement.

Nunn and his colleagues suggest that the staggered sleeping shifts are not an accident but an adaptation.

"A lot of older people go to doctors complaining that they wake up early and can't get back to sleep," Nunn said. "But maybe there's nothing wrong with them. Maybe some of the medical issues we have today could be explained not as disorders, but as a relic of an evolutionary past in which they were beneficial.”

Maybe. Maybe not. It's quite possible that older adults' sleep issues are just that: issues, and signs of an aging body. We'll need a lot more research on the subject before we can say for sure. In the meantime, let's cut Grandma some slack. Evolutionary advantage or no, we all just want to sleep.

A Generic EpiPen Coming in Early 2019 Could Save You Money

Brand-name EpiPens at a Congressional hearing on the escalating cost of the drug in 2016
Brand-name EpiPens at a Congressional hearing on the escalating cost of the drug in 2016
Alex Wong/Getty Images

For an incredibly common, life-saving medication, EpiPens (epinephrine auto-injectors) are surprisingly difficult for many consumers to get ahold of. Their cost has skyrocketed in recent years from less than $100 for a pack of two to more than $600. They’ve gotten so expensive that some EMTs have resorted to using syringes to manually administer epinephrine rather than purchasing the standard auto-injectors, which are almost exclusively made by the pharmaceutical company Mylan. Generic options have been slow to come to market, but according to Business Insider, a recently approved EpiPen rival is coming in the first few months of 2019, and it could save consumers a significant chunk of change.

The drug’s developers have had an unusually hard time getting the new EpiPen alternative, called Symjepi, onto store shelves. The drug was approved in 2017, but the company, Adamis Pharmaceuticals, had trouble finding investors. Now, Novartis, the Swiss-based pharmaceutical giant that manufactures drugs like Ritalin, is releasing the drug through its Sandoz division (perhaps most famous for it role in discovering LSD in the 1930s).

Symjepi will cost $250 out-of-pocket for a pack of two doses. That’s 16.6 percent less than the Mylan-authorized generic EpiPen or Teva’s generic EpiPen, which both sell for $300. It differs a bit from its rivals, though, in that it’s a pre-filled, single-dose syringe rather than a spring-loaded auto-injector. Auto-injectors are plastic, pen-like devices that keep the needle shielded until the moment of injection, and are specifically designed to help make it easier for untrained (even squeamish) people to use in an emergency. With this version, patients will need to remove a needle cap and inject the needle. Just like the EpiPen, though, it’s designed to be injected in the upper thigh, through clothing if necessary.

If you have health insurance, the difference in cost may not matter as much for you as a consumer, depending on your plan. (I personally picked up a two-pack of Mylan-authorized generic Epipens at CVS recently for $0, using a manufacturer’s Epipen coupon to knock down what would have been a $10 copay.) But it will matter considerably for those with high-deductible plans and to insurers, which, when faced with high costs, eventually pass those costs on to the consumer either through higher co-pays or higher premiums. It also affects agencies that buy EpiPens for emergency use, like local fire departments. And since EpiPens expire after just a year, the costs add up.

However, there’s currently a shortage of EpiPens on the market, according to the FDA, making it more important than ever to have other epinephrine drugs available to those at risk for serious allergic reactions.

[h/t Business Insider]

Brain-Eating Amoeba Kills Seattle Woman Who Used Tap Water in Her Neti Pot

CDC/Dr. Govinda S. Visvesvara, Wikimedia Commons // Public domain
CDC/Dr. Govinda S. Visvesvara, Wikimedia Commons // Public domain

If you use a neti pot to clear out your sinuses, there's one important rule you should always follow: Don't fill it with tap water. Doing so could land you a sinus infection, or worse, a potentially fatal disease caused by a brain-eating amoeba. Although the latter scenario is exceptionally rare, a 69-year-old woman in Seattle died from doing just that, The Seattle Times reports. Experts are also warning that these infections could become more common as temperatures in the northern hemisphere continue to rise.

Physicians at Seattle's Swedish Medical Center initially thought the woman had a brain tumor. She was brought into the emergency room following a seizure, and a CT scan of her brain seemed to reveal a tumor-like mass. The only other known symptom she had was a red sore on her nose, which was previously misdiagnosed as rosacea. When surgeons operated on her the following day, they noticed that "a section of her brain about the size of a golf ball was bloody mush," neurosurgeon Dr. Charles Cobbs told The Seattle Times. "There were these amoeba[e] all over the place just eating brain cells. We didn't have any clue what was going on, but when we got the actual tissue we could see it was the amoeba."

She died a month later of an infection called granulomatous amoebic encephalitis (GAE), according to a recent case report published in the International Journal of Infectious Diseases. The disease is caused by a single-celled amoeba called Balamuthia mandrillaris, and it's extremely deadly. Of the 109 cases between 1974 and 2016, 90 percent were fatal.

According to the FDA, some bacteria and amoebae in tap water are safe to swallow because acid in the stomach kills them. However, when they enter the nasal cavity, they can stay alive for long periods of time and travel up to the brain, where they start eating their way through tissue and cells. Another brain-eating amoeba called Naegleria fowleri can cause a similar disease, except it acts faster and can cause death in just a few days. Although it's also rare, it's usually found in warm freshwater, and infections start by getting contaminated water up one's nose while swimming or by using a nose irrigation device filled with tap water.

Dr. Cynthia Maree, an infectious disease doctor at the Swedish Medical Center, said the changing environment could facilitate the spread of these infections. "I think we are going to see a lot more infections that we see south (move) north, as we have a warming of our environment," Maree says. Researchers say these amoebae are still little-understood. Future studies would need to be conducted to learn more about the risk factors involved.

[h/t The Seattle Times]

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