Body Basics
By Catherine O’Neill Grace
Sleep on It
PROPER REST IS CRITICAL TO MANAGING DIABETES AND YOUR HEALTH
Do you keep your partner up at night with your snoring, snorting and interrupted sleep? The problem may be more serious than a couple of bad dreams or an uncomfortable pillow. Your nighttime noisemaking may be a symptom of obstructive sleep apnea.
"Obstructive sleep apnea, or OSA, is an increasingly common chronic disorder characterized by repetitive upper airway blockage during sleep," says Dr. Esra Tasali, assistant professor of medicine in the pulmonary and critical care department at the University of Chicago. Airway blockages lead to drops in the oxygen level in the blood, which in turn causes what Tasali calls "sleep fragmentation."
People with OSA may suffer from symptoms such as snoring, pauses in breathing during sleep (often noticed by a spouse or roommate), and gasping during sleep. These interruptions can happen hundreds of times each night.
We all know what it feels like to wake up after a restless night. Imagine, says Dr. Xavier A. Preud'Homme, who studies sleep at Duke University, if you woke your partner up once a minute throughout the night.
"You'd see the next day how that partner is irritable, sleepy and unable to concentrate. That's what sleep apnea does," he says.
Shakespeare wrote that sleep "knits up the ravel'd sleeve of care." He was right. It also helps our cells recover from the stresses of the day and our psyches work out the problems that our lives present — but only when we sleep well.
Chronic lack of sleep can lead to a constellation of problems. People with OSA wake up in the morning unrefreshed, they have morning headaches, and they're likely to feel sleepy during the day.
If you suspect that you have sleep apnea, talk to your doctor, who can give you a simple screening questionnaire about daytime sleepiness, frequent nighttime waking, snoring and other symptoms.
But OSA causes even more worrisome symptoms than a little daytime drowsiness. Untreated, sleep apnea is associated with high blood pressure, stroke and other cardiovascular diseases, says Tasali, as well as memory issues and depression.
Then there's the diabetes connection. Tasali says there is a prevalence of OSA in people with type 2 diabetes. In fact, studies suggest that anywhere from 23 percent to 75 percent of people with OSA also have type 2 diabetes. And those with OSA who don't have diabetes may well develop it: A recent study at the Yale University School of Medicine confirmed that patients with OSA are at increased risk of developing type 2 diabetes.
Yale's Dr. Nader Botros says sleep apnea may activate the body's natural "fight or flight" response. This causes a series of biochemical events in the body, including the production of high levels of the hormone cortisol, which can lead to insulin resistance and glucose intolerance — early indicators of diabetes.
Obesity is a major risk factor for OSA, says Tasali. Data from the 2005 "Sleep in America" poll conducted by the National Sleep Foundation indicate that as many as one in four adults — and 57 percent of obese individuals — are at high risk for OSA. "Rapidly growing evidence suggests that OSA and type 2 diabetes — but not type 1 — may be linked, even if the patient is not obese," Tasali says.
Treatment for sleep apnea can give you (and your partner) the gift of a good night's sleep.
If you suspect that you have sleep apnea, talk to your doctor, who can give you a simple screening questionnaire about daytime sleepiness, frequent nighttime waking, snoring and other symptoms. If your responses suggest that you have sleep apnea, you'll likely be counseled to undergo a sleep study. Called polysomnography, this process involves monitoring your brain waves, breathing patterns and blood oxygen levels while you are asleep in the lab setting.
Treatment for sleep apnea can give you (and your partner) the gift of a good night's sleep. It also may improve your diabetes. Studies have shown that a treatment called continuous positive airway pressure (CPAP), used at night, improves insulin resistance and, as a result, blood sugar levels in patients who have both sleep apnea and type 2 diabetes.
A CPAP machine treats sleep apnea by forcing air up through a person's nose via a silicon mask during sleep, keeping the airway open. "CPAP is the gold standard treatment for obstructive sleep apnea," says Tasali. She adds that while there is a need for more clinical evidence on the long-term beneficial effects of CPAP treatment, patients who use CPAP feel more alert and energetic, and their blood pressure is better regulated.
"Some CPAP studies suggest significant improvement in insulin sensitivity and glucose control," she says.
So sleep well. You'll feel better in the morning!