Evaluation of a Single-Channel Portable Monitor for the Diagnosis of Obstructive Sleep Apnea

Study Objective: To validate the ApneaLINK (AL) as an accurate tool for determining the presence of obstructive sleep apnea (OSA) in an at-risk sleep clinic population in a home test environment. Methods: Consecutive participants referred with the suspicion of OSA were evaluated in the home with the AL portable monitor (AL Home), followed by simultaneous data collection with diagnostic polysomnography (PSG) and AL in the sleep laboratory (AL Lab). Prevalence, sensitivity, specifi city, and ROC curves were calculated for PSG vs. AL Lab, PSG vs. AL Home, and AL Lab vs. AL Home test. Pearson correlations and Bland-Altman plots were constructed. Results: Fifty-three (55% female) participants completed the entire study. The mean age of the population was 45.1 ± 11.3 years, and body mass index was 35.9 ± 9.1 kg/m 2 . The prevalence of an apnea hypopnea index (AHI) ≥ 15 in the cohort was 35.9%. The results demonstrated a high sensitivity and specificity of the AL respiratory disturbance index (RDI-AL) compared with the AHI from the PSG. The AL Lab had the highest sensitivity and specificity at RDI-AL values ≥ 20 events/h (sensitivity 100%, specificity 92.5%). The AL Home was most sensitive and specific at an RDIAL ≥ 20 events/h (sensitivity 76.9%, specificity 92.5%). The Pearson correlations for PSG vs. AL Lab and PSG vs. AL Home were ρ = 0.88 and ρ = 0.82, respectively. The BlandAltman Plots demonstrated good agreement between the methodologies.