Snoring can be a sign of life-threatening sleep apnea
by Eve Becker
Loud, disruptive snoring is certainly no treat, as any afflicted spouse will attest. But snoring, especially when accompanied by occasional gasps for breath in the middle of the night and excessive daytime sleepiness, can be a sign of something significantly more serious.
Obstructive sleep apnea—when a person intermittently stops breathing during sleep—is a potentially life-threatening condition that can contribute to a host of health problems including an increased risk of high blood pressure (hypertension), heart attack and stroke. Individuals also may be more likely to suffer from excessive daytime sleepiness, diabetes, depression, sexual dysfunction, gastro esophageal reflux disease and difficulties with memory and concentration.
Certainly, it’s a bigger problem than just a noisy night’s sleep.
In obstructive sleep apnea, the upper airway intermittently narrows or even collapses during sleep. Patients may stop breathing for 10 seconds or longer, and this may happen five or more times an hour. In the most severe cases, it can happen nearly 150 times per hour.
“When you have sleep apnea, blood oxygen levels drop and your body creates an arousal mechanism to get you to open up your airway and breathe,” says Dr. Babak Mokhlesi, associate professor of medicine and director of the Sleep Disorders Center and Sleep Fellowship Program at the University of Chicago.
“The hormones released by the body during apneas increases the heart rate and blood pressure on and off throughout the night. This intermittent and cyclical drop of blood oxygen levels, sleep fragmentation and surges in excitatory hormones lead to an increased risk of developing hypertension, heart disease and stroke.”
Obesity is the prime risk factor, though not the only one. “Hands down, as soon as you get above age eight, it’s obesity that’s driving sleep apnea,” says Dr. James Wyatt, director of the Sleep Disorders Service and Research Center at Rush University Medical Center. For young children, sleep apnea is often due to enlarged tonsils or adenoids.
In patients who are overweight, fatty deposits can build up inside the throat and make the upper airway crowded, Wyatt explains. During the day, pharyngeal dilator muscles need to work harder to keep the upper airway open. But that reflex doesn’t work as well when patients go to sleep. At night, the muscles are overly fatigued, and the upper airway can get sucked closed.
“When the airway sucks closed, the body’s fight-or-flight alarm system wakes you up briefly, turns on the muscles to open up the airway, and typically, you take one or two big breaths and fall back to sleep,” Wyatt says. These apneic events are almost always accompanied by snoring between episodes.
The awakening is usually so brief that patients don’t remember it, though bed partners might hear a snorting, choking or gasping sound. This pattern can repeat itself over and over, all night long.
Undiagnosed obstructive sleep apnea sufferers might complain of tossing and turning during sleep, frequent awakenings during the night, waking up with a headache, and feeling irritated and unrested. Use of alcohol and sleeping pills increases the frequency and duration of breathing pauses in people with sleep apnea.
“Every time the brain has to wake you up to resume breathing, it prevents patients from getting into deeper restorative sleep, which leads to an increase in daytime sleepiness and a host of problems,” Wyatt says. “When your body’s alarm system fires up, it causes a brief spike in blood pressure. If that happens dozens or hundreds of times per night, it can lead to long-term cardiovascular damage and an increased risk for heart attack and stroke. There’s also an increased risk for major accidents, injuries or even death because of daytime sleepiness.”
Sleep apnea can have cardiovascular, neurocognitive and metabolic risks, Mokhlesi adds. “It leaves sleep fragmented. Despite spending eight hours in bed, these individuals can be tired. They can doze off easily in meetings or can fall asleep while driving. It can affect their cognitive function. Their reaction times may be slower, and that can put them at increased risk of motor vehicle accidents.”
Several factors increase the risk of sleep apnea, including where and how fat is distributed in the body (with a higher risk in individuals who deposit more fat in their waist and neck as opposed to the hips), whether a person naturally has a small airway or one that is more open, and whether the upper airway dilator muscle tone is strong or weak, Mokhlesi says. Many of these factors are genetically determined, which is why sleep apnea can cluster in families.
Sleep apnea occurs in all age groups. It is more common in men, although it may be under diagnosed in women, Mokhlesi says. About 9 – 12 percent of middle-aged men and 2 – 7 percent of women have moderate or severe sleep apnea.
At sleep centers, people undergo overnight sleep studies to find out how often they stop breathing or have shallow breathing. Their sleep is monitored to record breathing, brain activity, heart rate and rhythm, eye movements, leg movements and oxygen levels in the blood.
Currently, there is no medication that can treat sleep apnea.
Instead, the most effective treatment is continuous positive airway pressure (CPAP) therapy. With CPAP therapy, patients wear masks placed over their nose, or both nose and mouth, while they sleep. The CPAP machine provides pressurized air through the mask to keep the upper airway open.
Since sleep apnea is a chronic condition, patients need to use CPAP for the long haul. But many don’t comply.
“It is a long-term condition that requires long-term compliance with CPAP therapy,” says Mokhlesi. But only about 50 percent of patients are very adherent to CPAP therapy, he says. Some 15 percent of patients either have sworn off CPAP or are not willing to try it, leaving 35 percent as mixed users—those willing to try CPAP but who have trouble with the masks or the machine.
That’s why it’s important to go to a sleep center that’s accredited by the American Academy of Sleep Medicine, Wyatt says. At an accredited sleep center, experts in CPAP adherence can work with individuals who have trouble with CPAP, adjusting the pressure settings and the fit of the mask.
Other sleep apnea treatments are less effective. Weight loss helps, whether through a weight-loss program or through bariatric weight-loss surgery, but sustained weight loss is difficult for many patients.
Some patients undergo surgery to open up more space in their upper airway, but only 50 percent of patients see significant improvement after surgery, Wyatt says.
Some dentists offer oral appliances, called oral mandibular advancement devices, to bring the lower jaw forward at night and to prevent the tongue from falling back over the airway, opening up more space in the back of the throat. But these devices work best for people who have a normal body weight or are only slightly overweight, who do not have severe sleep apnea and whose sleep apnea is significantly worse when they sleep on their back rather than side or stomach, Wyatt says.
Positional therapy, with devices to prevent an individual from sleeping on their back, can work for those who only have sleep apnea when they sleep on their back but not on their side. Most individuals with sleep apnea, however, have breathing problems no matter which position they sleep in, Mokhlesi says.
Many patients do not realize the severity of their daytime sleepiness, Wyatt says. Once they undergo treatment with CPAP, they are amazed at the difference it makes in their day-to-day functioning and overall health.
With the significant health risks of obstructive sleep apnea, it turns out that Mom might have been right: There’s nothing like a good night’s sleep.
Published in Chicago Health Summer 2011