These are some of the most common questions asked about the HSAT.
Why consider a HSAT rather than an in-lab sleep study?
- Many commercial insurers now require use of home sleep apnea testing.
- The home sleep apnea is a low-cost way to evaluate your breathing during sleep with fewer sensors and wires than an in-lab sleep study. You can sleep in your own bed and to keep to your usual routine.
What does the HSAT include?
- The test records air flow (breathing), chest movement (effort), oxygen saturation, snoring, heart rate, and sleeping position. It allows us to identity times when you stop breathing or when shallow breathing causes your oxygen levels to fall.
What are the HSAT limitations?
- The HSAT is not a sleep study. It does not record brain activity, eye movements, muscle activity, or heart rhythm. This means we cannot tell when you are asleep or when you wake up. We can’t determine when you dream or when you move. We can’t identify arrhythmias.
- Without a sleep tech to monitor the recording, the equipment may become disconnected or fail to record part of the night.
- Even if required by an insurer, the HSAT cannot be used to prove that weight loss, dental treatment, or surgical treatment was able to eliminate sleep apnea.
- There is no such thing as a normal HSAT. Even in patients with a high pre-test probability of sleep apnea, it may fail to confirm the diagnosis. If the HSAT is normal, that does not mean that your breathing during sleep is normal.
How accurate is the HSAT?
- The home test was designed to confirm a diagnosis of obstructive sleep apnea in patients who are very likely to have it. This means people with excessive daytime sleepiness, loud snoring, and episodes of observed apnea or difficulty breathing during sleep. In these cases, the home test usually confirms the diagnosis of obstructive sleep apnea.
- The HSAT is less reliable in patients with severe insomnia and in patients with fewer symptoms of sleep apnea.
- The home test often underestimates the severity of the sleep apnea. This means the sleep apnea may be worse than the report suggests.
What if the HSAT fails to confirm a diagnosis of sleep apnea?
- If the HSAT is negative, then the next step is an in-lab sleep study. At this point the insurer should authorize the test.
Who cannot have a HSAT?
- Patients with significant heart and lung diseases like congestive heart failure should not have a home test. These patients are more likely to have central sleep apnea, low oxygen saturation, and difficulty ventilating during sleep. In-lab sleep studies are needed for these patients.
- Patients with severe insomnia spend much of the night awake, and the HSAT is unable to accurately distinguish normal breathing that occurs during the time spent awake from breathing during sleep. In patients with insomnia and suspected sleep apnea, an in-lab study is required.
- Patients who are severely overweight are more likely to have difficulty ventilating during sleep and may need additional oxygen or ventilatory support in sleep. These patients should have in-lab studies.
- Patients with dementia or significant physical limitations may be unable to perform the home test. These patients should be studied in the lab where the sleep techs can record the necessary information.
- Patients with symptoms of other sleep disorders like narcolepsy, periodic limb movement disorder, REM sleep behavior disorder, or seizures require in-lab study.