Tsai HJ, Yang A, Tsai SJ, Ma Y, Kuo T, Yang C, Peng CK. Associations of Reduced Sympathetic Neural Activity and Elevated Baroreflex Sensitivity with NREM Sleep: Evidence from electroencephalogram- and Electrocardiogram-Based Sleep staging [Epub., ahead of print] DOI: 10.1097/PSY.0000000000001079
To explore the cardiovascular profiles of sleep. Autonomic neural controls in sleep regulation have been previously demonstrated; however, whether these alternations can be observed by different sleep staging approaches remains unclear. Two established methods for sleep staging – the standardized visual scoring and the cardiopulmonary coupling (CPC) analysis – were employed to explore the cardiovascular profiles of sleep.
Autonomic nervous system (ANS) is evidently associated with stable sleep, as indicated by the similar findings obtained from sleep stages regardless if sleep scoring is categorized by standardized visual scoring or CPC-analysis. Compared with REM or nocturnal wakening (nAW), the highest delta power and the lowest theta, alpha and beta powers of EEG, increased cardiac vagal activity and decreased vascular-sympathetic activities, along with a trend in elevated baroreflex sensitivity were observed during NREM (EEG) and Stable sleep (CPC). Such association between cardiovascular neural activity can be observed regardless of the sleep staging approach followed.
The findings of this study indicate that autonomic functions during sleep can be identified regardless of the sleep staging approach applied, standardized visual EEG-scoring or CPC-scoring. The data were in line with the assumption of the physiology behind the CPC sleep staging and further extends the knowledge of vascular-sympathetic modulation and the baroreceptor reflex interaction with sleep stages, categorized by a cardiovascular-based approach using either ECG or PPG sensors for data collection. The findings from CPC-staging were similar to the results obtained from the standardized visual EEG-scoring, supporting the important role of the ANS in regulating sleep. CPC-sleep staging offers automated sleep analysis on par with the reference standard but with the simplicity and convenience of consumer-type data collection making it optimal to track sleep quality in real time.