0179 Cardiovascular Responses to Sleep Deprivation and Psychological Stress Predict Actigraphic Sleep During Recovery

Abstract Introduction We assessed whether cardiovascular (CV) responses to total sleep deprivation (TSD) and to TSD and psychological stress predicted sleep measures during that night’s recovery. Methods Thirty-two healthy adults (ages 27-53; 14 females) participated in a five-day experiment under controlled conditions. During this experiment, CV measures were collected via blood pressure monitor or echocardiography at four assessment time points: 1) after two baseline 8h time in bed (TIB) nights; 2) in the morning of TSD (TSD AM; after 25h of TSD); 3) in the evening of TSD following a modified Trier Social Stress Test, which induced psychological stress (TSD PM; after 34h of TSD); and 4) after two recovery nights (R1=10h TIB; R2=8h TIB). Seated heart rate (HR), cardiac index (CI), stroke volume (SV), systemic vascular resistance index (SVRI), left ventricular ejection time (LVET), systolic and diastolic blood pressure (SBP and DBP), and mean arterial pressure (MAP) were collected. Wrist actigraphy (Actiwatch Spectrum) assessed sleep measures during the first recovery night (R1) including the timing of sleep onset, offset, and midpoint, sleep duration, wake after sleep onset (WASO), sleep efficiency (SE), percent sleep, and sleep onset latency (SOL). Pearson’s correlations assessed relationships between TSD AM and TSD PM CV responses and R1 sleep indices (p 0.05 was significant). Results Longer LVET in the morning and in the evening of TSD were significantly associated with longer sleep duration and later sleep offset during recovery (r: 0.386-0.471; r2: 0.149-0.222). In addition, longer LVET in the evening of TSD was significantly associated with higher WASO during recovery (r=0.385; r2=0.148). By contrast, lower HR in the morning (r=−0.449; r2=0.202) and in the evening (r=−0.499; r2=0.249) of TSD were significantly related to a later sleep offset during recovery. Conclusion To the best of our knowledge, this is the first demonstration that CV responses to TSD and to TSD and psychological stress, are reflected in the duration, quality, and timing of actigraphic sleep during the immediate recovery night in healthy adults. Overall, LVET and HR during sleep deprivation may be unique biomarkers for determining sleep responses during recovery that night. Support (if any) NASA grants NNX14AN49G and 80NSSC20K0243 (NG)