Sensitivity and specificity of telemedicine-based long-term pulse-oximetry in comparison with cardiorespiratory polygraphy and polysomnography in patients with obstructive sleep apnoea syndrome

Abstract

We investigated the feasibility of night-time pulse-oximetry telemedicine. We compared polysomnography (PSG) as the gold standard with simultaneously recorded pulse-oximetry from a wrist pulse-oximeter. The results were evaluated by a sleep specialist and compared with outpatient polygraphy. A total of 135 consecutive patients (mean age 55 years, mean body mass index 31.6 kg/m(2)) were studied. Patients with minor, moderate and severe PSG findings were grouped together and compared to those without PSG findings; the resulting sensitivity was 1 and specificity 0.35. In addition, patients with and without minor PSG findings were grouped together and compared to those with moderate and severe PSG findings; the resulting sensitivity was 0.66 and the specificity was 0.98. The receiver operating characteristic (ROC) of telemedically-evaluated oximetry was superior to that of outpatient polygraphy. In contrast, the automatic assessment of severity based on the Oxygen Desaturation Index was unsatisfactory. For patients suspected of sleep related breathing disorders (SRBD), telemedically-evaluated pulse-oximetry is able to identify those who should be referred to a sleep laboratory for definitive diagnosis and treatment. The technique appears to be suitable for first screening in all patients at risk for SRBD.