Pulse Oximeters Undercount Sleep Apnea in Black Patients
A Mass General Brigham study finds oxygen-based sleep apnea scoring misses more breathing events in Black participants than in white participants.
Updated on Nov. 4, 2026 in Sleep Disorders
Live Poll
Do you trust that common medical tests give accurate results for everyone?
Pulse oximeters, which measure blood oxygen by shining light through the body, undercount sleep apnea breathing events in Black patients, according to a study published in the American Journal of Respiratory and Critical Care Medicine. Researchers found the proportion of airflow-defined events meeting a 4% oxygen-desaturation criterion was about 20% lower in Black than white participants.
Why it matters
Pulse oximetry racial biases had already been documented in other clinical settings, including among patients with Covid-19, but the extent of the bias on sleep apnea scoring was previously unknown. The findings suggest oxygen-based severity scores may understate disease in Black patients, with heart-rate-based scoring showing no comparable racial gap.
The proportion of airflow-defined breathing events meeting the 4% oxygen-desaturation criterion was 21% lower in Black than White participants in MESA and 20% lower in SHHS. Heart-rate-based scoring showed no comparable racial difference in either cohort.
The players
Mass General Brigham
A Boston-based academic health system whose investigators conducted the study examining pulse oximetry and sleep apnea scoring.
American Journal of Respiratory and Critical Care Medicine
A peer-reviewed clinical journal published by the American Thoracic Society that carried the study.
The details
Researchers compared sleep apnea severity scores based on blood oxygen desaturation monitored by pulse oximetry against airflow and heart-rate response metrics. They analyzed data from the Multi-Ethnic Study of Atherosclerosis (MESA) and the Sleep Heart Health Study (SHHS). Pulse oximeters emit light through the body and measure absorption, and melanin and other pigments in darker skin can absorb some of that light.
Timeline
November 4, 2026: Mass General Brigham published the study findings news release.
Health Landscape
The finding extends racial biases in pulse oximetry first documented among Covid-19 patients into sleep medicine. It raises questions about whether oxygen-based scoring used across sleep clinics in the United States systematically understates disease in Black patients.
Patients with sleep apnea who have been assessed using oxygen-based scores may have had their severity understated, so clinicians may need to consider heart-rate and airflow measures alongside oximetry. Patients should discuss any concerns about how their sleep apnea is scored with their sleep physician.
The takeaway
Pulse oximetry readings may understate sleep apnea in Black patients, so severity scores based on oxygen alone may not capture the full picture. Heart-rate-based measures showed a more consistent link to cardiovascular risk across both cohorts.
Further reading
For related coverage, see Sleep Disorders reporting across the United States.
More information
Read the full published study in American Journal of Respiratory and Critical Care Medicine for complete methods and results.
Live Poll
Do you trust that common medical tests give accurate results for everyone?
