A home sleep study, also known as a home sleep apnea test (HSAT or HST), is a diagnostic tool used to identify sleep-related breathing disorders. It involves using a portable device to monitor various physiological signals while an individual sleeps in their own bed.
What a Home Sleep Study Detects
A home sleep study primarily focuses on diagnosing obstructive sleep apnea (OSA), a condition characterized by repeated pauses in breathing during sleep due to a blocked airway. The device measures factors like breathing patterns, airflow, blood oxygen levels, heart rate, and snoring, indicating OSA severity.
While highly effective for OSA, home sleep studies do not comprehensively detect all sleep disorders. Conditions like central sleep apnea, narcolepsy, restless leg syndrome, and REM sleep behavior disorder require a more extensive in-lab sleep study (polysomnography) for diagnosis. In-lab studies monitor additional parameters such as brain activity (EEG), eye movements, and muscle activity, not measured by home devices.
The Process of Getting Started
Initiating a home sleep study requires a consultation with a healthcare provider. Your doctor will assess your symptoms, medical history, and determine if an HST is appropriate for your situation. If a home sleep study is recommended, your physician will provide a prescription for the device.
Following the prescription, you will receive the home sleep study device, either by mail or by picking it up from a clinic. Along with the device, you will receive instructions on its use. Home sleep study devices vary, but include sensors measuring respiratory effort, airflow via a nasal cannula, blood oxygen saturation with a pulse oximeter placed on a finger, and heart rate. Some devices also track body position and snoring.
Performing the Study at Home
To prepare for the study, avoid alcohol and caffeine on the day of the test, as these can interfere with sleep patterns and test results. Follow your normal routine and sleep in your usual position. Do not apply lotions or creams before bed, as they can prevent sensors from adhering properly.
When you are ready for sleep, follow the provided instructions to attach the sensors. This involves placing a finger probe for oxygen levels, securing a nasal cannula to monitor airflow, and possibly attaching a chest belt to measure breathing effort. Ensure all connections are secure and comfortable. Some devices have status lights to indicate proper setup and recording.
Once the device is set up, activate it according to the instructions and go to sleep as you normally would. If a sensor detaches during the night, reattach it if possible. The device is designed to record data throughout your sleep cycle, so it should remain on until you wake up in the morning.
After the Study: Results and Follow-Up
After completing the overnight study, the device must be returned as instructed, by mail or to the clinic where it was obtained. The collected data is then downloaded and analyzed by a board-certified sleep physician. This analysis includes interpreting measurements such as the apnea-hypopnea index (AHI), which indicates the average number of breathing interruptions per hour.
Once the analysis is complete, your healthcare provider will schedule a follow-up appointment to discuss the results. During this consultation, the physician will explain the findings, confirm diagnoses, and outline potential treatment options if a sleep disorder is identified. If the home study results are unclear or suggest a more complex issue, an in-lab sleep study might be recommended for a more comprehensive evaluation.