0747 Association of a novel EEG biomarker of sleep depth with cardiac autonomic modulation in adolescents

Abstract Introduction The odds ratio product (ORP), a continuous spectral EEG measure of sleep depth, increases in the transition to adolescence and with psychiatric/behavioral disorders; however, its association cardiac physiology has been largely unexplored. Heart rate variability (HRV), EKG autonomic balance, includes HR oscillations at low frequencies (LF), standard deviation between normal heart beats or R-R intervals (SDNN) root mean square successive differences heartbeats (RMSSD), reflecting sympathetic vs. parasympathetic tone. We aimed examine longitudinal non-rapid eye movement (NREM) ORP 24-hour HRV adolescents. Methods studied 606 children (Md=9y), whom 418 were followed-up as adolescents (Md=16y) from Penn State Child Cohort. extracted NREM 9s following cortical arousals (ORP-9) 9-hour, in-lab polysomnography (PSG), frequency time-domain indices 24-h Holter monitoring immediately PSG. stratified data into daytime nighttime periods. Linear regression analyses examined associations change ORP-9 adolescent indices, adjusting for age, race, sex, BMI, metabolic syndrome score, AHI, insomnia symptoms, actigraphy-TST, childhood indices. Results While there no significant childhood, cross-sectional adolescence. Longitudinally, greater increase since was associated lower Log-LF SDNN (both P< 0.05). Similar found ORP-9, addition higher RMSSD (all Cross-sectionally, HR, yet Log-LF, RMSSD, both periods Conclusion Greater developmental declines depth arousability during are impaired balance adolescence, independent apnea, insufficient sleep. These also suggest coupling fine-grain measures sleeping brain those sympathetic/parasympathetic modulation, which may inform cardiovascular risk early life. Support (if any) NIH (R01HL136587, R01MH118308, UL1TR000127)