It's something our health depends on, but it's often hard to get.
That something is a good night's sleep.
Researchers are only beginning to understand the consequences of interrupted sleep, and the long-term health effects of poor sleep habits.
In this week’s Exploradio, we visit a sleep clinic where doctors are developing new treatments for an age-old problem.
We’re visiting one of the Cleveland Clinic’s sleep labs.
It’s actually a hotel room near the Clinic where director Ralph Downey and his team conduct sleep studies.
It has all the ammentities of a luxury suite, a big comfy bed, TV, and kitchenette.
What’s not so comfy is the tangle of wires and straps that Downey uses to monitor his subjects.
“Most of these electrodes go on the head to measure brain waves," says Downey. There’re also straps to measure respiration, sensors for oxygen and carbon dioxide levels, cuffs to sense leg movement.
Diagnosing sleep issues means a lot of data, and down the hall from the bedroom banks of computers gather information from each night’s batch of patients.
Downey’s lab operates 24 hours a day, six days a week, seeing around 10,000 people a year.
He brings up a recent sleep study which graphs a condition they see in many of those patients.
The monitor fills with a dozen or so squiggly lines showing eye movements, breathing, brain waves, and the dip into REM sleep.
Downey says this person was having a vivid dream, “so there’s like ten rapid eye movements during this epoch of sleep," over the course of just 30 seconds.
But, he says, it’s anything but restful. “You can see this person, every minute, is stopping their breathing.”
This is a case of sleep apnea – continuous interruptions in breathing. Another line on the chart shows its devastating consequences.
“Their oxygen drops from 97 percent to 90 percent,” says Downey. That triggers the person to startle awake, and, “if you’re waking up to resume your breathing every 30 seconds to every minute, you’re essentially getting no continuous sleep.”
He says this disrupted sleep cycle happens each night to around 22 million Americans with sleep apnea.
Sleep and heart health
Dr. Reena Mehra is head of sleep research at the Cleveland Clinic.
She says sleep apnea puts a lot of stress on the body's systems. "You have to work a lot harder to breathe. It’s almost like you’re undergoing a heart stress test while you're sleeping.”
In a recent study she found that these cycles of oxygen starvation and saturation flood the body with tissue damaging free radical compounds, "that can increase inflammation and be another pathway that increases cardiovascular risk.”
She says sleep apnea can lead to damaged blood vessels, high blood pressure, and ultimately much higher rates of heart disease and stroke.
Mehra says there are several ways to treat sleep apnea, number one being weight loss.
A new technology, hypoglossal nerve stimulation, is now being prescribed for certain types of sleep apnea.
“That’s an implanted device that has a lead that goes to the nerve that innervates the tongue,” says Mehra, and an electrical pulse keeps the tongue out of the way during sleep.
Mehra says around 80 Clinic patients have had it implanted so far, with promising results.
Beyond sleep apnea
Sleep apnea is only one of around 90 sleep issues Mehra encounters at the Clinic.
Cleveland Clinic sleep center director Dr. Nancy Foldvary-Schaefer studies how these and other sleep disorders are tied to deeper brain functions.
“We see people in the clinic every day who have sleep problems but memory problems, or sleep problems and seizures," and her research investigates to what extent they are connected.
Her research shows that when people with epilepsy sleep better, they have fewer seizures. Sleep problems can also signal the onset of Alzheimer’s.
She’s pushing for acceptance in the medical community of sleep as medicine.
“Maybe sleep therapies can be part of therapy in neurological disease, which I think is very cool.”
Foldvary-Schaefer says we are seeing an epidemic of sleep deprivation in this country, especially among young people.
“People cut sleep short thinking that it’s something that’s elective.”
She says sleep, or lack of it, effects every organ system in the body, but our understanding of exactly how those interactions occur remains a mystery.
"Sleep," she says, “is a tough thing to study.”