Brasília, November 1, 2026. A study published in August evaluated whether a smartwatch could help identify adults at risk of moderate to severe obstructive sleep apnea. The research tested the Samsung Galaxy Watch 6 in a selected group of participants and found high sensitivity at the default cutoff, but more limited specificity. The findings suggest potential for screening—not diagnosis by the watch.
What was evaluated
The prospective study was published in the Journal of Clinical Sleep Medicine on August 27, 2026, and publicized by the American Academy of Sleep Medicine (AASM) in October. It enrolled 152 adults aged 22 and older who already had a diagnosis of moderate to severe apnea or had a high pretest probability of having the disorder. One hundred and forty-seven completed both nights of laboratory polysomnography; between these sessions, they also wore the watch at home for at least three nights. The Galaxy Watch results were compared with those of polysomnography, the reference used in the study.[1] [2]
For the primary analysis, moderate to severe apnea was defined as an apnea-hypopnea index (AHI) of 15 or more events per hour. At the watch’s default threshold, the study found a sensitivity of 94.1% and a specificity of 66.7%. The area under the ROC curve was 0.94. The confidence intervals were wide, especially for specificity, warranting caution when interpreting the estimates.[1]
How to interpret the numbers
Sensitivity describes the proportion of participants with moderate to severe apnea identified by the device under the study conditions. Specificity describes the proportion of those who did not meet that level of severity and were correctly classified. Thus, a sensitivity of 94.1% does not mean that a person who receives an alert has a 94.1% probability of having apnea, or that the watch is correct for 94 out of every 100 users.
The researchers also tested an alternative threshold in the same sample, adjusted to the group’s data. At that threshold, sensitivity was 82.4% and specificity was 94.9%. This difference shows that classification depends on the criterion used; the threshold adjusted in the study should not be treated as a universal rule for other groups, watches, or software versions.[1]
Another important limitation is participant selection. This was not a random sample of people who had bought a smartwatch: the volunteers already had a diagnosis or had previously screened as high risk. The observed performance cannot automatically be generalized to people without symptoms, to other models, or to the Brazilian population as a whole. The study also received financial and material support from Samsung Electronics, as disclosed by the authors.[1]
Screening is not diagnosis
The AASM described the feature as a potential screening tool to help refer people at risk for formal evaluation. This is different from confirming the disease. A normal watch reading does not rule out apnea, and an alert does not confirm the diagnosis. The AASM clinical guideline recommends that questionnaires and algorithms alone not be used to diagnose apnea in adults; investigation should take place within a clinical evaluation and, when indicated, with an appropriate sleep study.[2] [3]
For some adults without complex medical conditions, home sleep apnea testing may be an alternative to polysomnography, provided it is indicated by a qualified professional and interpreted in the context of the clinical history. The AASM emphasizes that the decision should not be based solely on the device’s automated scoring. If a home test is negative, inconclusive, or technically inadequate and suspicion persists, the guideline recommends considering polysomnography.[3] [4]
When to seek evaluation
Habitual snoring, breathing pauses observed by another person, awakenings with choking or a feeling of suffocation, and persistent daytime sleepiness are reasons to talk with a healthcare professional. These signs do not establish a diagnosis on their own, but they help guide the investigation. Learn more about sleep apnea symptoms and evaluation and how polysomnography works.
The study broadens the discussion about how devices already used in everyday life could help identify risk. For now, the evidence presented relates to a specific model, in a high-risk group and under defined research conditions. The watch may be a starting point for a clinical conversation; it does not replace testing, professional interpretation, or individual evaluation. The research does not demonstrate that all smartwatches detect apnea with the same performance.
Sources for this report
- Alavi A. et al. Smartwatch-based detection of moderate-to-severe and high-risk obstructive sleep apnea. Journal of Clinical Sleep Medicine, August 27, 2026.
- American Academy of Sleep Medicine. Study finds a smartwatch can help screen for obstructive sleep apnea, October 13, 2026.
- Kapur V. K. et al. Clinical practice guideline for diagnostic testing for adult obstructive sleep apnea. Journal of Clinical Sleep Medicine, 2017.
- American Academy of Sleep Medicine. Clinical use of a home sleep apnea test: updated position statement, 2025.
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