Automatic identification of apnea through acoustic analysis for at-home screening.

Objective: Although many studies have analyzed breathing sounds in the diagnosis of obstructive sleep apnea syndrome, the recording of snoring sounds at home is hampered by the various background noises of daily life. Recordings also frequently include talking during sleep, which may infringe the privacy of patients.

Materials And Methods: A recording system used a bone conduction microphone to record snoring sounds. This microphone reduced background noise. A simple system transmitted recorded breathing sound data for screening at a hospital as envelope data instead of complete sound recordings, thereby decreasing data volume and protecting privacy.

Results: In periods in which blood oxygen levels (SpO₂) were drastically decreased, the probability of apnea as deduced from the envelope curve of breathing sounds was consistent with SpO₂ values.

Conclusions: This method provides a basis for telemonitoring of sleep apnea syndrome.