Trial Outcomes & Findings for Belun Ring Platform With an Improved Algorithm for OSA Assessment (NCT NCT04885062)

NCT ID: NCT04885062

Last Updated: 2026-04-13

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

136 participants

Primary outcome timeframe

1 overnight sleep study (1 Day)

Results posted on

2026-04-13

Participant Flow

Participant milestones

Participant milestones
Measure
UH-Participant
Potential participants with suspected OSA will be identified from the schedule of the UH Beachwood and Bolwell sleep labs.Those subjects who satisfy the study inclusion and exclusion criteria will be approached and invited to participate in the study. Belun Ring: The Belun Ring sensor will be applied to the proximal phalanx of the index finger in the non-dominant hand of the participating individuals prior to their sleep onset in the sleep lab and will be removed upon awakening at the end of the sleep period on the following morning. The attended in-lab sleep study will be performed simultaneously in a standard fashion. PSG: All patients scheduled for attended overnight in-lab polysomnography (PSG) in our 2 sleep labs 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 vis-à-vis with the results of the PSG on the same patient.
Overall Study
STARTED
136
Overall Study
COMPLETED
136
Overall Study
NOT COMPLETED
0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Belun Ring Platform With an Improved Algorithm for OSA Assessment

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
UH-Participant
n=84 Participants
Potential participants with suspected OSA will be identified from the schedule of the UH Beachwood and Bolwell sleep labs.Those subjects who satisfy the study inclusion and exclusion criteria will be approached and invited to participate in the study. Belun Ring: The Belun Ring sensor will be applied to the proximal phalanx of the index finger in the non-dominant hand of the participating individuals prior to their sleep onset in the sleep lab and will be removed upon awakening at the end of the sleep period on the following morning. The attended in-lab sleep study will be performed simultaneously in a standard fashion. PSG: All patients scheduled for attended overnight in-lab polysomnography (PSG) in our 2 sleep labs 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 vis-à-vis with the results of the PSG on the same patient.
Age, Continuous
48.3 years
STANDARD_DEVIATION 14.4 • n=193 Participants
Sex: Female, Male
Female
42 Participants
n=193 Participants
Sex: Female, Male
Male
42 Participants
n=193 Participants
Race/Ethnicity, Customized
Race · African American
52 Participants
n=193 Participants
Race/Ethnicity, Customized
Race · Caucasian
24 Participants
n=193 Participants
Race/Ethnicity, Customized
Race · Hispanic
1 Participants
n=193 Participants
Race/Ethnicity, Customized
Race · Asian
2 Participants
n=193 Participants
Race/Ethnicity, Customized
Race · Others
1 Participants
n=193 Participants
Race/Ethnicity, Customized
Race · Unknown
4 Participants
n=193 Participants
Region of Enrollment
United States
84 participants
n=193 Participants
Body Mass Index (BMI)
38.7 kg per square meter
STANDARD_DEVIATION 9.3 • n=193 Participants
Apnea-Hypopnea Index (AHI)
15.8 events per hour
n=193 Participants

PRIMARY outcome

Timeframe: 1 overnight sleep study (1 Day)

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
UH-Participant
n=84 Participants
Potential participants with suspected OSA will be identified from the schedule of the UH Beachwood and Bolwell sleep labs.Those subjects who satisfy the study inclusion and exclusion criteria will be approached and invited to participate in the study. Belun Ring: The Belun Ring sensor will be applied to the proximal phalanx of the index finger in the non-dominant hand of the participating individuals prior to their sleep onset in the sleep lab and will be removed upon awakening at the end of the sleep period on the following morning. The attended in-lab sleep study will be performed simultaneously in a standard fashion. PSG: All patients scheduled for attended overnight in-lab polysomnography (PSG) in our 2 sleep labs 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 vis-à-vis with the results of the PSG on the same patient.
To Evaluate the Ability of the Belun Ring Pulse Oximeter to Gauge the Apnea-Hypopnea Index (AHI)
-1.0 events per hour
Standard Deviation 9.0

SECONDARY outcome

Timeframe: 1 overnight sleep study (1 Day)

To determine the accuracy of BLS-100 sleep stage parameters to classify the human sleep stage (Wake, REM and Non-REM) by comparing to the classification results of in-lab PSG.

Outcome measures

Outcome measures
Measure
UH-Participant
n=67107 30s Sleep Epochs
Potential participants with suspected OSA will be identified from the schedule of the UH Beachwood and Bolwell sleep labs.Those subjects who satisfy the study inclusion and exclusion criteria will be approached and invited to participate in the study. Belun Ring: The Belun Ring sensor will be applied to the proximal phalanx of the index finger in the non-dominant hand of the participating individuals prior to their sleep onset in the sleep lab and will be removed upon awakening at the end of the sleep period on the following morning. The attended in-lab sleep study will be performed simultaneously in a standard fashion. PSG: All patients scheduled for attended overnight in-lab polysomnography (PSG) in our 2 sleep labs 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 vis-à-vis with the results of the PSG on the same patient.
Sleep Stage Parameters
Accuracy of Wake Stages
88 percentage of correct classification
Sleep Stage Parameters
Accuracy of NREM Stages
82 percentage of correct classification
Sleep Stage Parameters
Accuracy of REM Stages
90 percentage of correct classification

Adverse Events

UH-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

Dr. Ambrose A. Chiang

University Hospitals-Cleveland Medical Center

Phone: 216-791-3800

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place