If you think you may suffer from obstructive sleep apnea or some other sleep breathing disorder, there are several simple tests you can take that may suggest you should discuss the possibility with your health care provider. Remember, though, that one of the best tests may be a complaint by your bed partner that you snore loudly or that you stop breathing repeatedly while you’re asleep.
Four tests that you can take right now are the American Sleep Apnea Association’s own Snore Score, the STOP-BANG screener, the Epworth Sleepiness Scale, and the Berlin Sleep Questionnaire. STOP-BANG asks for you to enter your body-mass index. If you don’t know what your BMI is, the National Heart Lung and Blood Institute will help you calculate it.
If you suspect that you have sleep apnea, the usual first step is to discuss your suspicions with your primary care physician. If you don’t have a primary care physician, you can go directly to a clinician who is a sleep specialist. But check your health care insurance coverage first. Some policies require you to see a primary care physician first, and some policies limit the sleep centers and testing facilities whose services they will pay for. Unfortunately, you may discover that your policy offers limited or no coverage for the diagnosis and treatment of sleep apnea, in which case you may wish to switch insurers if and when you can.
Whichever kind of physician you consult initially, it can be helpful for you to prepare in advance a detailed account of your medical history as it may be relevant to sleep apnea. The ASAA is collaborating with Arbor Medicus to offer you a free interactive online HistoryTaker that will help you do just that. Here are the details.
Sleep specialists come from a variety of medical backgrounds. They may be pulmonologists (lung specialists), otolaryngologists (ears, nose, and throat), neurologists (brain and nerves), psychiatrists (mental health), or primary care physicians–internists and family practitioners. Some dentists also have special training in the treatment of sleep disordered breathing, which includes sleep apnea. You can check the credentials of specialists at the web sites of the American Board of Internal Medicine and the American Board of Sleep Medicine. You should feel free to ask any doctor you see about his or her credentials and the diagnostic procedures to be followed.
A definitive diagnosis of sleep apnea can be made only with a sleep study conducted during a visit to a sleep lab, usually overnight, or a home study performed with special equipment. Some sleep centers are accredited by the American Academy of Sleep Medicine and you can find them listed here. Others that are just as qualified, however, may choose not to pay the cost of accreditation or may be in the process of obtaining it.
A sleep study generates several records of activity during several hours of sleep, usually about six. Generally, these records include an electroencephalogram, or EEG, measuring brain waves; an electroculogram, or EOG, measuring eye and chin movements that signal the different stages of sleep; an electrocardiogram, EKG, measuring heart rate and rhythm; chest bands that measure respiration; and additional monitors that sense oxygen and carbon dioxide levels in the blood and record leg movement. None of the devices is painful and there are no needles involved. The testing procedure as a whole is known formally as “polysomnography,” and the technician who supervises it is usually a “registered polysomnographic technologist,” or RPT. Usually the bedroom where the test is conducted is more like a comfortable hotel room than a hospital room.
Your doctor might prescribe a “split-night study,” in which the first hours are devoted to diagnosis. If obstructive sleep apnea is found, the patient is awakened and fitted with a positive airway pressure device. The remainder of the patient’s slumber is then devoted to determining how well he or she responds to PAP therapy.
A substantial amount of data is generated by a sleep study, but the most crucial is the apnea-hypopnea index, or AHI. An apnea is a complete cessation of breathing for 10 seconds or longer. A hypopnea is a constricted breath (more than one-fourth, less than three-fourths) that lasts 10 seconds or longer. The index number is the number of apneas and hypopneas the sleeper experiences each hour. An AHI of 5 to15 is classified as mild obstructive sleep apnea; 15 to 30 is moderate OSA; 30 or more is severe OSA. If you are diagnosed with OSA, its severity is one of the factors you and your sleep specialist will weigh as you explore your treatment options.
While polysomnography in a fully equipped sleep lab is regarded as the “gold standard” for sleep apnea diagnostics, your sleep specialist may decide that given your circumstances and your symptoms the findings produced in a home study will be sufficient to make an accurate diagnosis. A home study, especially if it is self-administered (as most are), is definitely cheaper, and some patients are unable to conform to the sleep lab’s procedures. Home studies are coming into steadily wider use.
The cost of diagnosing and treating sleep apnea is significant, generally well over $1,000, and if PAP therapy is prescribed, charges will be ongoing. If you are uninsured or underinsured, you may be tempted to delay action. Be aware, though, that the consequences of untreated sleep apnea, could lay a heavy cost on you as well. Diagnosis and, if necessary, treatment may be well worth the price.
THE MORNING AFTER
A guide to understanding your sleep study:
If you are reading this, you’ve probably had a sleep study. Which means that you’ve spent a night in a polysomnographic laboratory, hooked up to devices that generate an encyclopedic amount of information on what’s going on in your brain and blood, your lungs and limbs.
Neither you–nor the doctor treating you–will view more than a minuscule fraction of this data. The sleep lab will reduce the 1,000 or so pages of material down to its essence. Depending on the lab, whether you self-referred, and how your doctor practices, you might ee a paragraph, a one-page summary, or a six-page document complete with graphs. But even in a short format, there’s an awful lot of information, and it can be awfully confusing. “People do tend to get lost in the numbers,” admits Dr. Rochelle Goldberg, a specialist in sleep medicine who is past president of the American Sleep Apnea Association. And it’s not just numbers-there are all kinds of acronyms and jargon to master.
In order to help you get a better handle on these numbers and alphabet soups, and a better comprehension of what they quantify and signify, here is a guide to polysomnography. The material in this guide comes from current and former associates of the ASAA: Dr. Richard E. Waldhorn, a professor and clinician at Georgetown University and former association president; Goldberg; and registered polysomnographic technologist David Polaski. In addition, we drew from a report of the American Academy of Sleep Medicine Task Force, chaired by Dr. W. Ward Flemons, published in the May 1999 issue of Sleep.
Quantity of Sleep
The first thing looked at is the total sleep time, or TST. This is an objective measure, based on the readings from electrodes recording brain waves, of the amount of time you actually sleep during your study. Very often, this measurement is at odds with people’s subjective perception of how much they slept. They will feel as if they hardly slept a wink, but the report indicates they were out for six hours. The electrodes don’t lie.
Sleep Efficiency and Latency
The ratio between the total sleep time and the total recording time, or TRT, is called the sleep efficiency. People who have significant difficulties in either initiating or maintaining sleep have diminished sleep efficiency, which can be related to various conditions and disorders, including depression. The number of minutes between the time the light is turned out and the person falls asleep is the sleep onset latency. Normally, it takes about 15 minutes to fall asleep. A significantly shorter onset latency–the proverbial falling asleep as soon as your head hits the pillow–might seem desirable, but in fact is an indicator of sleep deprivation. This could suggest a disorder, or it could be just a sign to slow down. Regardless of the demands of work and family, and the enticements of television and the web, you need at least seven and a half hours of sleep a night.
Once you drop off, you should progress through four stages of increasingly deep, dreamless sleep and into a fifth stage during which dreaming–characterized by rapid eye movement–occurs. Over the course of the night, you will cycle repeatedly between Non-REM and REM sleep. The structure of these cycles–poetically known as “sleep architecture”–reveals whether you are getting the restorative sleep you need to feel and be well. Stage 1, the very lightest sleep, should only be 5 percent of the total sleep time, and should only occur at the beginning of the night. The still fairly light Stage 2 sleep should represent about 55 to 60 percent of the TST. Deep sleep–also known as “slow wave” sleep–takes place in Stages 3 and 4, and should account for about 20 percent of the TST. This is the form of sleep that, as Shakespeare wrote, “knits up the raveled sleave of care.” If it is truncated or absent, you will not feel rested the next day. Your sleep study measures the time spent in each stage, in minutes and as a percentage, and the latencies between the time you fall asleep and the time you enter Stage 4 and REM sleep, respectively.
Arousals and Awakenings
Arousals–interruptions of sleep lasting 3 to 15 seconds–can occur spontaneously or as a result of sleep-disordered breathing or other sleep disorders. Each arousal sends you back to a lighter stage of sleep. If the arousal last more than 15 seconds, it becomes an awakening. You are usually not aware of arousals, but may be aware of awakenings. The number of arousals and awakenings is registered in the study, and reported as a total number and as a frequency per hour of sleep, which is referred to as an index. The higher the arousal index, the more tired you are likely to feel, though people vary in their tolerance of sleep disruptions. As few as five arousals per hour can make some people feel chronically sleepy. In the worst cases of SDB, the index can be 100 or more.
The arousals and awakenings that occur when things go awry in your breathing while you’re asleep can arise from a glitch in the central nervous system–i.e., the brain “forgets” to breathe–but more commonly have a mechanical cause. (There are also “mixed” episodes, involving both elements, but these are relatively rare.) The mechanical malfunction occurs when the soft structures in the back of the throat collapse into the airway, reducing the amount of air that makes its way into your lungs and, as a consequence, the amount of oxygen in your bloodstream. In an apnea, airflow is reduced by at least 80 percent; in a hypopnea, the range of the reduction is 50 to 80 percent. The report indicates the number of times each occurs, as a nighttime total and as an index of events per hour. This latter number is referred to as either the apnea-hypopnea index or the respiratory disturbance index. An index of 5 to 14 indicates a mild level of breathing–and sleep–disturbance. From 15 to 30 is moderate; greater than 30 is severe. The associated drops in blood oxygen levels, known as desaturations, are also measured and categorized. Normal saturation is around 95 percent. A desaturation to 86 percent is mild, a reduction to 80 to 85 percent is moderate, and a drop to 79 percent or less is severe.
These indexes, Goldberg stresses, are not fuzzy concepts, but hard data generated by easily measured electrical systems. Nevertheless, they don’t tell the whole story. The severity of your sleep apnea (and what treatment you need) can’t really be gauged by a machine. Your doctor will look at the numbers, but will need to put them into a clinical context. Consequently, it’s vital that you track and report what you experience from day to day. Do you get sleepy while reading or watching television? That’s a very mild level of impairment, and might not be cause for concern. Or are you fighting off sleep–or falling asleep–during activities such as eating, talking, walking, and driving? That’s a medical emergency. So don’t get too hung up in the numbers; they’re enormously helpful, but they don’t replace words.
In addition to the items covered above, the polysomnogram looks at your heart rhythm, and determines if there are any abnormalities. Another important part of the study is the assessment of limb movement, since leg movement can constitute another sleep disorder. And yes, someone is listening to–though not measuring in decibels–your snoring, which is probably the symptom that got you to the lab in the first place.
About 70 percent of people with obstructive sleep apnea are overweight or obese. Their health care professionals usually encourage them to lose weight.Surprisingly, there have been few formal studies of how effectively weight loss leads to lesser, lighter snoring and diminished incidents of apnea and hypopnea during sleep. Despite this, anecdotally practitioners report striking improvements in both OSA and snoring among patients who lose weight.
In some situations a physician may wish to prescribe weight loss medications to an overweight or obese patient with OSA.1
Nasal decongestants are more likely to be effective in cases of snoring or mild sleep apnea. In some cases, surgery is an effective way to improve airflow through the nose.
Some people snore or have sleep apnea only when sleeping on their back. Such people can eliminate or reduce airway blockage simply by learning to sleep on their side.
The traditional technique to induce side-sleeping is dropping a tennis ball in a sock and then pinning the sock to the back of the pajama top. There are also a couple of companies that make a products designed to discourage supine sleeping. Visit the Online Directory of Products and Services for additional infomation.
Positional therapy generally works only in mild cases of OSA. In more severe cases, the airway collapses no matter what position the patient assumes.
Surgery is often effective in treating snoring. It is less effective in treating obstructive sleep apnea.
The challenge that confronts the surgeon is determining what part of the upper airway is causing the obstruction to airflow. There are many possible sites, and conventional sleep testing does not identify the area the surgeon should modify. If the surgeon does not treat that site in the airway, or if there are multiple sites of obstruction, it is unlikely that the sleep apnea will diminish to a degree that eliminates the need for other treatment.
Given the several sites where airway obstruction may exist, there are several types of operations currently used to treat sleep apnea. The most common is uvulopalatopharyngoplasty, or UPPP. The success rate of this operation is about 50 percent. Some surgeons have achieved very high success rates using multiple, staged operations.2 Nonetheless, most authorities recommend routine re-assessment for sleep apnea after surgery. See the caution below. There’s more about surgery here.
Most children with snoring or sleep apnea have enlarged tonsils, or adenoids, or both. In 75 percent of those cases, surgical removal of these tissues cures sleep breathing problems.
The American Academy of Pediatrics has endorsed removal of the tonsils and adenoids as the initial treatment of choice for sleep breathing problems in children. There is more information children’s sleep apnea and its treatment here.
Oral appliances look like the mouth guards worn by football players. The oral appliances for treating sleep apnea and snoring are specially designed for that purpose. The appliance is worn in the mouth during sleep. Most appliances work by positioning the lower jaw slightly forward of its usual rest position. This small change is, in many people, enough to keep the airway open during sleep. You can simulate the effect of an oral appliance with a simple experiment. If you make a snoring sound right now and, in the middle of it, thrust your jaw forward, you will see that the snoring sound stops. The American Academy of Sleep Medicine has endorsed oral appliance therapy for selected patients with sleep apnea. Many authorities recommend routine assessment for sleep apnea after oral appliance therapy has been applied. See the caution below. More information is available here.
Positive Airway Pressure Devices
Positive airway pressure machines, used with a variety of breathing masks, are the most widely used treatment for moderate and severe sleep apnea. They have been endorsed by the American Academy of Sleep Medicine. The mask, worn snugly over the nose, or sometimes nose and mouth, during sleep, supplies pressurized air that flows continuously or intermittently into the sleeper’s throat. The increased air pressure prevents the sleeper’s airway from collapsing. The pressurized air is supplied through a flexible tube from one of several types of machines: CPAP (continuous positive airway pressure), BiPAP (bilevel positive airway pressure), VPAP (variable positive airway pressure), and so on. Studies of the effect of PAP therapy show that OSA patients who consistently use their machines feel better and, as a result of the reduction of apnea and hypopnea episodes during sleep, encounter fewer complications of the disease. There’s more information about PAP therapy here.
A variant on the PAP device is Provent. Operating on the same principal of keeping the lungs full and the upper airway open, this therapy does not require electricity to operate or the use of a humidifier. Information is available through our Online Directory of Products and Services. Although PAP devices are not used to treat snoring alone, they do eliminate snoring in addition to treating obstructive sleep apnea.
Abstinence from alcohol before bedtime is an important part of treating sleep apnea.
In one study, several persons who received cardiac pacemakers were reported to have shown an improvement in their sleep apnea. No major organizations have endorsed this type of treatment, however. Further studies are underway.
Alternative healing methods are also in use. There is some evidence that playing the didgeridoo or other wind instruments may help in managing OSA. In Brazil, acupuncture researchers who are physicians report positive results in treating OSA with acupuncture.
Snoring, and certain details of snoring, can be a valuable early-warning alarm that sleep apnea is present. Treating snoring can remove this warning system. Just as seeing smoke is a warning that a fire may be burning, hearing snoring is a warning that sleep apnea may be present. And just as smokeless fires may be discovered late, with unfortunate consequences, so too may snore-free sleep apnea. Thus, when surgery or oral appliances are used to treat snoring, it is important to check for sleep apnea on a regular basis afterwards.
Anesthesia and Pain Medicine
The presence of sleep apnea presents special challenges to the administration of anesthesia and pain medications that may affect respiration or relax muscles. Since most people who have sleep apnea don’t know it, the anesthesiologist or pain clinician is well advised to screen the patient for OSA before proceeding. Should it be determined there is a likelihood that OSA is present, the next move is to order a sleep study to make sure or, at a minimum, to take the precautionary steps that should be taken with a patient whose sleep apnea has been diagnosed.