Who should consider itand who shouldn't?
In the not-too-distant past, if your doctor suspected you had sleep apnea, spending a night in a sleep lab hooked up to a multitude of wires was the only way to obtain a definitive diagnosis. Recently, however, portable sleep monitoring devices have been gaining in popularity, because they offer several advantages over lab-based testing.
Most notably, you can undergo testing in the comfort and privacy of your own bedroom. And, if you live in an area where there are few, if any, sleep labs or where there are waiting lists to have the test performed (delays of up to 10 months have been reported), home monitoring may decrease the waiting time for diagnosis and beginning treatment, if needed.
Although lab-based testing remains the preferred method of diagnosing sleep apnea, results from the Sleep Heart Health Study and other research indicate that in some instances, correctly conducted home tests are nearly as accurate. The keys to success lie in:
- knowing if you're a candidate for home monitoringmany people with pulmonary diseases are not;
- choosing the right devicehome monitors vary widely in their ability to gather reliable information and produce useful results; and
- consulting sleep experts to oversee the monitoring and make the diagnosis.
How Home Testing Works
Home testing devices are small and lightweight and are classified into one of three groups based on the type of information the device provides.
Type 4. These are the simplest devices. Most record only blood oxygen levels, but some record airflow as well. This information is insufficient to make a diagnosis of sleep apnea.
Type 3. In addition to blood oxygen level, these commonly used devices record airflow, breathing effort, and heart ratethe minimum amount of information needed to diagnose sleep apnea. However, type 3 devices tend to under-diagnose the condition because they do not monitor brain activity and thus the total amount of sleep.
Type 2. Of the portable monitoring devices, these systems are most similar to the type 1 devices used in a sleep lab and gather the most information, including airflow, breathing effort, blood oxygen level, brain activity, eye movements, muscle movements, and heart rate.
For home monitoring, sensors are attached at appropriate locations on the body and information is transmitted through an electrode to a sleep recorder box that is about the size of a cell phone. There is a small but real risk that some electrodes will fall off during the night, which could affect the results. However, some portable monitors have an audible alarm that is set off when this occurs.
Getting Help From an Expert
For the most reliable results, the sensors should be attached by a technician or technologist from a sleep lab accredited by the American Academy of Sleep Medicine (AASM; to find an accredited lab, go to www.sleepcenters.org or call AASM at 708-492-0930). A technician may come to your home to set everything up. Or you may be asked to come to the sleep lab to be outfitted with the electrodes, and you'll go home wired up.
If you plan to apply the sensors yourself, you should first receive instruction from an appropriately trained healthcare professional. AASM guidelines recommend that the data obtained be scored by a sleep technologist and then evaluated by a sleep specialist (instead of automatically interpreted by a computer).
Following the test, you should meet with a doctor who is board certified in sleep medicine to discuss your results and develop a treatment plan if sleep apnea is diagnosed. To find such a sleep specialist, ask your primary-care physician for a referral or visit www.sleepcenters.org. In addition, you can confirm whether your sleep specialist is board certified by visiting the American Board of Medical Specialties at www.abms.org or calling 866-ASKABMS (275-2267).
If your results indicate sleep apnea and you used a type 2 device, your doctor will likely begin treatment. If you did not use a type 2 device or if your results are negative and your doctor still suspects sleep apnea, you may be asked to repeat the sleep study in a lab.
Is Home Testing Right For You?
To find out, you will first need to undergo an evaluation by a sleep specialist. AASM guidelines state that individuals between the ages of 18 and 65 who have clear symptoms of moderate to severe sleep apneaexcessive daytime sleepiness and loud snoringcan consider using a home monitoring device. While snoring itself does not always indicate sleep apnea, if your bed partner reports that you repeatedly stop breathing and then gasp for breath while sleeping, there is a good chance that you have the disorder.
AASM guidelines also note that portable home monitoring should not be used by anyone with a serious medical condition such as moderate to severe pulmonary disease, heart failure, stroke, or other sleep disorders like insomnia or restless legs syndrome. One reason for this recommendation is that people with these health problems tend to have trouble sleeping. If you're not sleeping while you're being monitored, a device that doesn't track brain activity won't be able to tell that you're awake. Instead, the device simply will indicate that you aren't having many apneas, which could lead to the conclusion that you don't have sleep apneawhich may not be the case.
This is a problem for anyone who isn't a good sleepernot just people with a serious illness. Some sleep specialists take issue with this advice, noting that type 2 devices, which include brain activity monitoring, will correctly indicate whether or not the person being monitored is really sleeping. Consequently, even some people with a serious medical condition can take advantage of home monitoring as long as they use a type 2 device.
Medicare and private insurance carriers typically pay for polysomnography, which costs about $1,500. Until recently, Medicare only covered continuous positive airway pressure (CPAP), the most common treatment for sleep apnea, if the condition was diagnosed in a sleep lab. But in 2008, Medicare coverage for CPAP was expanded to include people diagnosed using a home sleep test. And in March 2009, Medicare decided to pay for home testing with a Type 2, 3, or 4 monitor, as long as symptoms of sleep apnea are present. Many private insurance companies typically follow Medicare's lead.