Preparing for a Test
It is important to have a consultation with a board-certified sleep physician who can fully evaluate your symptoms, perform a comprehensive physical examination, and help to determine the appropriate testing for you.
In some cases, such as restless legs syndrome (RLS) or insomnia caused by a circadian disorder, no testing may be required. Most sleep disorders require a diagnostic test to elucidate the cause.
One of the considerations will be whether a home sleep apnea test (HSAT) is adequate or if a formal in-center diagnostic polysomnogram (PSG) will be needed. If mild sleep apnea is present, the HSAT may be inconclusive, especially in younger, healthy people of normal weight, and people assigned female at birth before the onset of menopause. This kind of testing is also not appropriate to diagnose central sleep apnea, narcolepsy, sleep-related behaviors called parasomnias, periodic limb movements of sleep, and some other disorders. In some cases, the PSG will be done if the HSAT fails.
Make sure to ask all questions you have prior to the testing. It can be helpful to view the testing equipment and the space used for the in-center testing. This may identify necessary accommodations and relieve some anxiety about what to expect.
Day of the Study
To prepare for a test, try to optimize the conditions that will enhance sleep during the study. Consider waking a little earlier than usual. This will build sleep drive and make it easier to fall asleep that night. Do not take naps during the day. Avoid the consumption of all caffeine—skipping coffee, tea, soda, chocolate, energy drinks, and other caffeinated products. Caffeine has a half-life that can last up to six hours, blocking the adenosine signal for sleep, and it may make it hard to sleep.
Be active, following your routine exercise regimen. Eat meals and snacks as you normally would. Eat dinner before coming to an in-center sleep study. If you normally consume alcohol in the evening, discuss with a sleep physician whether you should adhere to this routine. In most cases, you should.
Spend the last one to two hours of the day relaxing, preparing your body and mind for sleep. Put away work. Avoid anything that might prompt anxiety or be upsetting (such as reading the news or social media). It can be a nice time to read a book, or listen to relaxing music. Minimize exposure to screen light, and go to bed close to your normal bedtime. Make sure that you have the feeling of sleepiness or drowsiness before preparing to start the test.
Tips to Reduce Insomnia
Insomnia is a condition that commonly overlaps with other sleep disorders that require sleep testing, including sleep apnea and disruptive leg movements in sleep. Once settled into bed, it is common to have an unusual awareness of the need to fall asleep. Even people who normally do not experience insomnia may have some trouble. Rather than simply dozing off, as may often occur, more time may initially be spent awake. This can lead to a cascade of distressing and anxious thoughts. It may be important to redirect this thinking before it derails the testing experience.
As needed, consider the use of relaxation techniques. Focused breathing, progressive muscle relaxation, and guided imagery may be helpful. Distract yourself by trying to recall the details of a recent dream or movie that you have seen. Counting sheep is a tried and true method, but counting down by repeatedly subtracting 6 starting from 300 may also be distracting. Trying to recall the presidents of the United States in order, the names of the states starting on the northwest coast, or your grade school teachers’ names can be equally mentally engaging. Any of these will give the mind a focus—and distract from the need to fall asleep. Then, almost as a surprise, sleep comes.
If an awakening occurs during the night, avoid checking the clock or looking at a smartphone. Do not turn on the television or lights to read. Instead, roll over and try to fall back asleep by re-engaging the relaxation techniques. If needed, it is okay to get up to urinate, but keep the lights low.
In some cases, it may be important to prioritize insomnia treatment with cognitive behavioral therapy for insomnia (CBTI) prior to proceeding with testing.
Discuss the use of a sleeping pill with the sleep physician well before the testing; prescriptions will not be available if you wait until the night of the study. These medications generally should not be taken in the middle of the night, as the morning hangover effects may make it unsafe to drive.
What to Do If a Test Fails
How much data is needed with a sleep study? Surprisingly, a successful study can be completed with only a few hours of sleep. Prolonged wakefulness with home testing may lead to a false negative study, meaning that the test does not demonstrate sleep apnea because too much time is spent lying awake with normal breathing. This may prompt an in-center polysomnogram to be performed.
If signals are lost, the duration of this interruption may determine whether a test may have to be repeated. The in-center PSG may be more technically successful, as the sleep technologist can come in to fix a wire that goes astray.
A Word From Verywell
Set yourself up for success by getting your questions answered prior to the testing. This should help lay your fears and anxiety to rest. Follow the tips to avoid insomnia, including the advice to follow during the day of the study. If you worry that you won’t be able to sleep enough to successfully complete the test, ask the sleep physician about the possibility of using a sleeping pill. Otherwise, use the distraction techniques to relax and ease yourself into sleep. In the morning, the testing will be over, and soon you will have answers you need.
