Reliability of Manual and Automatic Scoring of Single Channel Nasal Airflow Device (ApneaLink) in Determining Moderate or Severe Obstructive Sleep Apnea Syndrome

Background and Objective ApneaLink (AL) is a single-channel portable monitoring device that identifies apnea or hypopnea from nasal airflow and is commonly used for screening and diagnosis of obstructive sleep apnea (OSA). This study aimed to evaluate the reliability of automatic and manual scoring of AL in patients with moderate or severe OSA. Methods This was a retrospective single-center study. Consecutive patients who underwent AL and confirmatory standard polysomnography (PSG) for evaluation of OSA within a 3-month interval were included. Sensitivity, specificity and receiver operating characteristic curves for AL were calculated for automatic and manual scoring with the apnea-hypopnea index (AHI). Pearson correlations and Bland-Altman plots were computed. Results Eighty-one patients were included. Overall, their mean age was 56 ± 10 years, and 80% were male. A correlation was found between the AL and PSG AHI and the apnea index but not with the hypopnea index. AL showed high sensitivity (82.7%) for moderate OSA with a good area under the curve (AUC) value of 0.710. Compared with automatic scoring methods, manual scoring provided higher AUC and specificity as well as positive and negative predictive value. Conclusion sThis study shows a high level of agreement in the AHI between AL and PSG performed within 3 months. The result of manual scoring with AL was more in agreement with overnight PSG than the result of automatic scoring was