Trial Outcomes & Findings for Validation of a Novel Device for Screening Patients With Symptoms of Obstructive Sleep Apnea (NCT NCT04121923)

Results Overview

Apnea-Hypopnea Index (AHI) is defined as the total number of apnea and hypopnea events per hour of sleep, where higher values indicate more severe sleep-disordered breathing. In this study, standard overnight polysomnography(PSG) and Belun Ring pulse oximeter were simultaneously measured. The AHI derived from PSG data was served as the reference. The primary outcome evaluates the accuracy of the Belun Ring by calculating the difference in Ring-REI by the Belun Ring compared with AHI derived from PSG recordings for each participant. The difference was calculated as: Ring-REI (Belun Ring) - AHI (PSG). Negative values indicate that the Belun Ring estimated a lower AHI than PSG, while positive values indicate that the Belun Ring estimated a higher AHI than PSG. Summary statistics of these differences were used to assess agreement between the Belun Ring device and PSG in measuring sleep apnea severity.

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

70 participants

Primary outcome timeframe

1 overnight sleep study (1 Day)

Results posted on

2026-05-26

Participant Flow

Participant milestones

Participant milestones
Measure	Participant All patients scheduled for attended overnight in-lab polysomnography (PSG) will undergo PSG testing. On the same night of the PSG testing, these same patients will also wear the Belun Ring device. After the study, we will compare results of the Belun Ring device with the results of the PSG on the same patient. There will be no separate arm to test a different device. Belun Ring Pulse Oximeter: Belun Ring Pulse Oximeter allows measurement and analysis of oximetry, pulse rate, photo-plethysmography (PPG), and accelerometer signals from the proximal phalanx of index finger. Total sleep time (Ring-TST) and respiratory event index (Ring-REI) are estimated
Overall Study STARTED	70
Overall Study COMPLETED	50
Overall Study NOT COMPLETED	20

Reasons for withdrawal

Reasons for withdrawal
Measure	Participant All patients scheduled for attended overnight in-lab polysomnography (PSG) will undergo PSG testing. On the same night of the PSG testing, these same patients will also wear the Belun Ring device. After the study, we will compare results of the Belun Ring device with the results of the PSG on the same patient. There will be no separate arm to test a different device. Belun Ring Pulse Oximeter: Belun Ring Pulse Oximeter allows measurement and analysis of oximetry, pulse rate, photo-plethysmography (PPG), and accelerometer signals from the proximal phalanx of index finger. Total sleep time (Ring-TST) and respiratory event index (Ring-REI) are estimated
Overall Study Difficulty achieving an arbitrarily preset high-pass signal strength threshold	20

Baseline Characteristics

Race and Ethnicity were not collected from any participant.

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Participant n=50 Participants All patients scheduled for attended overnight in-lab polysomnography (PSG) will undergo PSG testing. On the same night of the PSG testing, these same patients will also wear the Belun Ring device. After the study, we will compare results of the Belun Ring device with the results of the PSG on the same patient. There will be no separate arm to test a different device. Belun Ring Pulse Oximeter: Belun Ring Pulse Oximeter allows measurement and analysis of oximetry, pulse rate, photo-plethysmography (PPG), and accelerometer signals from the proximal phalanx of index finger. Total sleep time (Ring-TST) and respiratory event index (Ring-REI) are estimated.
Age, Continuous	54.9 years STANDARD_DEVIATION 16.3 • n=50 Participants
Sex: Female, Male Female	23 Participants n=50 Participants
Sex: Female, Male Male	27 Participants n=50 Participants
Region of Enrollment United States	50 participants n=50 Participants
Body Mass Index (BMI)	30.5 kg per square meter STANDARD_DEVIATION 7.7 • n=50 Participants
Apnea-Hypopnea Index (AHI)	18.5 events per hour STANDARD_DEVIATION 15.4 • n=50 Participants

PRIMARY outcome

Timeframe: 1 overnight sleep study (1 Day)

Population: All participants underwent both Belun Ring and PSG measurements during the same night. Therefore, the same set of participants is included in both groups. Data are presented per measurement modality to comply with reporting requirements.

Apnea-Hypopnea Index (AHI) is defined as the total number of apnea and hypopnea events per hour of sleep, where higher values indicate more severe sleep-disordered breathing. In this study, standard overnight polysomnography(PSG) and Belun Ring pulse oximeter were simultaneously measured. The AHI derived from PSG data was served as the reference. The primary outcome evaluates the accuracy of the Belun Ring by calculating the difference in Ring-REI by the Belun Ring compared with AHI derived from PSG recordings for each participant. The difference was calculated as: Ring-REI (Belun Ring) - AHI (PSG). Negative values indicate that the Belun Ring estimated a lower AHI than PSG, while positive values indicate that the Belun Ring estimated a higher AHI than PSG. Summary statistics of these differences were used to assess agreement between the Belun Ring device and PSG in measuring sleep apnea severity.

Outcome measures

Outcome measures
Measure	Belun Ring Device n=50 Participants Participants wore the Belun Ring device during an attended overnight polysomnography (PSG) study. The device estimates respiratory event index (Ring-REI) based on oximetry, pulse rate, photoplethysmography (PPG), and accelerometer signals.	Polysomnography (PSG) n=50 Participants Participants underwent standard attended overnight in-laboratory polysomnography (PSG), which served as the reference method for measuring Ring-REI.
To Evaluate the Ability of the Ring-REI Measured by Belun Ring to Gauge the AHI Measured by PSG	16.2 events per hour Standard Deviation 10.6	18.5 events per hour Standard Deviation 15.4

Adverse Events

Participant

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Ambrose A. Chiang

University Hospitals-Cleveland Medical Center

Phone: 216-791-3800

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place