0792 Relationships Between Age, REM Sleep, and Sleep Disordered Breathing Across the First 24 Months of Life

Abstract Introduction Infant airway anatomy and immature central respiratory systems place infants at risk for sleep disordered breathing. Further, infant sleep is comprised of higher amounts of rapid eye movement (REM) sleep, with a steady decline across the first twenty-four months. Compared to the controlled breathing rate during non-REM (NREM), REM sleep has an erratic rate. The combination of immature anatomy and increased REM amount predispose infants to greater apnea risk, yet there is a poor characterization of age- and REM-associated changes in disordered breathing across the first twenty-four months. Methods We retrospectively analyzed 95 clinical sleep studies from 50 infants (M=10.5 months, SD = 7.6., F=24), each had one to four records, who were being evaluated for sleep disordered breathing. We investigated the average number of combined central and obstructive apnea events per hour, controlling for age of infant, and percentage of total sleep time in both NREM and REM, respectively, using a Poisson regression within the Generalized Linear Mixed Model (GLMM) framework. Results Infants slept on average 371 minutes (SD=121), of which approximately 33% (SD=12%) was spent in REM. We observed an average of 5.3 apnea events per hour (SD = 5), with a median of 3.5 IQR: 1.7, 7.9, unadjusted, which we found varied by age (p.05). During the first year, higher apnea event rates were observed at one and six months, while the lowest apnea rate occurred at three months of age. Between 12 and 24 months, rates stabilized, mirroring those observed at three months, but with a noticeable increase at 18 months. There was a strong relationship with REM sleep, with 3.2 times more apnea events per hour during REM versus nREM. This increased rate during REM was consistent across age, including when adjusted for the percentage of REM sleep and sex (RR=3.18, 95% CI 2.61, 3.89, p.001). Conclusion We observed a dynamic relationship between age, REM sleep, and total apnea events across the first twenty-four months of life. As infants are at higher risk for apnea, evaluating age- and REM-associated apnea changes may provide new assessment and intervention targets in sleep disordered breathing. Support (if any)