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