Sleep Trackers and Orthosomnia: Useful Data or Extra Worry?

How trackers estimate sleep

Most consumer devices use movement (accelerometers) plus heart rate and sometimes heart rate variability, skin temperature or blood oxygen to guess whether you are asleep and which stage you are in. A clinical sleep study measures brain waves directly with EEG. Consumer devices do not.

What they are good and bad at

Trackers are generally reasonable at estimating total sleep time and your schedule over weeks, especially if you sleep soundly. They are less accurate at detecting periods of quiet wakefulness (often counting them as sleep) and at classifying sleep stages. Numbers for deep sleep and REM should be treated as rough estimates. Different devices can give quite different results for the same night.

What the AASM says

In a 2018 position statement, the AASM said consumer sleep technologies can help engage people with their sleep health, but they are not a substitute for medical evaluation and, unless cleared by the FDA for that purpose, cannot be used to diagnose or treat sleep disorders. If a device flags something worrying, or you have symptoms, talk to a clinician.

Orthosomnia: when the score becomes the problem

In 2017, researchers writing in the Journal of Clinical Sleep Medicine described patients who became so preoccupied with improving their tracker data that it worsened their insomnia. They coined the term orthosomnia. Signs include:

• Feeling anxious when you see a low score, even if you feel fine
• Spending extra time in bed trying to raise your numbers
• Trusting the device over how you actually feel
• Checking data during the night

How to use a tracker well

• Focus on trends over weeks, not single nights.
• Use it to check habits: bedtime and wake time consistency, how alcohol or late caffeine affect you.
• Pay more attention to how you feel during the day than to stage breakdowns.
• Do not look at it in the middle of the night.
• If it makes you anxious, take a break of a week or two and see how you sleep.

When data should prompt a doctor visit

Some devices report blood oxygen dips, irregular heart rhythms or breathing disturbances. These features vary in accuracy and are not a diagnosis. However, if you also have loud snoring, gasping, pauses in breathing noticed by a partner, unrefreshing sleep or daytime sleepiness, ask your doctor about testing for sleep apnea.