A wearable ring oximeter for detection of sleep disordered breathing.

INTRODUCTION

Wearable devices have been developed that can continuously monitor physiologic variables. One device, Circul® (Bodimetrics Corp, Los Angeles, CA), with a form factor of a ring, measures several variables (SpO2, movement, heart rate).

OBJECTIVES

To evaluate the potential utility of this device in detecting sleep breathing disorders.

MATERIALS AND

METHODS

OSA severity measured by the oxygen desaturation Index (ODI) using a wearable oximetric Circul® ring (ODI as defined by 3 % desaturation - cODI3 %) was compared with the gold standard, polysomnography (PSG) in patients suspected of having sleep-disordered breathing. The Circul data was autoscored by the device's software; a technician scored the PSG data. The sensitivity (S), and specificity (E) for the different thresholds for cODI3 % compared to the PSG AHI and PSG ODI, were calculated.

RESULTS

164 patients (age = 44.8 years + 12.3 (SD)) were enrolled. Using the PSG-derived AHI as the reference for classification, the best cut-off points were: OSA = AHI ≥ 5: cODI3 % ≥ 4.3 (S 87.8 %, E 93.8 %); OSA = AHI ≥ 15: cODI3 % ≥ 13.1 (S 76 %, E 100 %); OSA = AHI ≥ 30 = : cODI3 % ≥ 16.2 (S 85.7 %, E 92 %); Using the ODI from the PSG as the reference for classification, the respective cut-off points were: OSA=ODI ≥ 5: cODI3 % ≥ 4.3 (S 93.4 %, E 88.9 %); OSA=ODI ≥ 15:cODI3 % ≥ 13.1 (S85.2 %, E98.4 %); OSA=ODI ≥ 30: cODI3 % ≥ 18.7 (S 98.4 %, E 92.2 %).

CONCLUSIONS

Circul® oximetry demonstrated good diagnostic accuracy compared to the gold standard in determining OSA severity. cODI3 % greater than 13 suggests that significant OSA might be present.