Detrended fluctuation analysis of photoplethysmogram pulse rate intervals in sleep disordered breathing

The fluctuation of heartbeat intervals is irregular and erratic in healthy young individuals. Sleep disordered breathing (SDB) influences the fluctuation of heart rate. In this study, we investigated the effects of SDB on heart rate fluctuations by analyzing the short- and long-range correlation of photoplethysmogram pulse to pulse intervals (PPIs). We recruited 160 children referred to British Columbia Children's Hospital for overnight polysomnography and recorded the photoplethysmogram (PPG) using the Phone Oximeter™. Detrended fluctuation analysis was applied to analyze the scaling behavior of PPIs time series in children with and without SDB. We found stronger short-range (10 to 40 pulses) and long-range (70 to 200 pulses) correlation in children with SDB. This reflects the loss of irregularity of heart rate in children with SDB.