LAUSR

Study objective: Current hypertension guidelines recommend that at-risk individuals be screened for obstructive sleep apnea (OSA). The Belun Ring is a wearable OSA diagnostic device worn on the palmar side of the proximal phalanx of the index finger. Methods: We recruited 129 participants (age: 60 ± 8 years, male sex: 88%, BMI: 27 ± 4 kg/m2) with hypertension and high cardiovascular risk for a simultaneous polysomnography and Belun Ring monitoring for one night. Epworth Sleepiness Scale score more than 10 was detected in 27 (21.0%) participants. Results: In the 127 participants who completed the study, the apnea–hypopnea index (AHI) derived from polysomnography was 18.1 (interquartile range: 33.0) events/h and that derived from the Belun Ring was 19.5 (interquartile range: 23.3) events/h [intraclass correlation coefficient: 0.882, 95% confidence interval (95% CI): 0.837–0.916]. A Bland–Altman plot showed the difference between the Belun Ring and polysomnography AHIs to be -1.3 ± 10.4 events/h. Area under the receiver operating characteristic for the Belun Ring AHI was 0.961 (95% CI: 0.932–0.990, P < 0.001). When the Belun Ring AHI of at least 15 events/h was used to diagnose OSA, the sensitivity, specificity, positive predictive value, and negative predictive value were 95.7, 77.6, 85.3, and 93.8%, respectively. The overall accuracy was 87.4%. The Cohen's kappa agreement was 0.74 ± 0.09 (P < 0.001). Similar results were obtained when the oxygen desaturation index was used to diagnose OSA. Conclusion: A high prevalence of OSA was detected in patients with hypertension and high cardiovascular risk. The Belun Ring is a reliable device for OSA diagnosis similar to polysomnography.