A Passive and Portable System for Monitoring Heart Rate and Detecting Sleep Apnea and Arousals: Preliminary Validation

The National Institutes of Health (NIH) Sleep Disorders Research Plan expresses a need for methods that can non-invasively monitor sleep characteristics. Forty subjects were tested using a novel, passive ballistocardiography-based system during an overnight study. We examined our system´s ability to measure heart rate as compared to EKG while we also investigated our system´s apnea and arousal detection capabilities as compared to conventional polysomnography. We found a strong correlation (r=0.972, p<0.0001) in average heart rate computed over 480 thirty-second epochs when our method was compared to EKG. Additionally, we achieved a sensitivity of 89.2% and specificity of 94.6% in the automated detection of apneas. Similarly we attained a sensitivity of 77.3% and a specificity of 96.2% in the detection of arousals. These preliminary results demonstrate the effectiveness of our portable ballistocardiography-based system as compared to polysomnography and show promise that high quality sleep assessment can be performed in a home environment