Comparing benign snores with apneic snores based on high frequency analysis

Snoring is the most common symptom of Obstructive Sleep Apnea (OSA). Several researchers have re ported differences in the power spectrum of both benign and apneic snorers. Conventionally, the frequency band analyzed was less than 5kHz. In this paper, we analyze the snore sound (SS) considering the spectrum at the high frequency band (HFB) 5kHz to 10kHz. We show the existence of a significant difference between 12 benign snoreres (Respiratory Disturbance Index, RDI=4.9±2.4 event/h; 1352 episodes) and 12 Apneic snoreres (RDI=34.7±23.5 event/h; 2153 episodes) on the HFB. Based on this observation, we propose a novel measure P for snore-based OSA screening. The developed measure could separate the 24-subject training data set into apnea/non apnea classes at sensitivity 83.3% and specificity 83.3%. These numbers suggest that HFB carries information that could be valuable for the classification of benign and apneic snorers compared to other band (below 5 kHz) used in the conventional work.