Effects of selective sleep deprivation on the hemodynamics of healthy individuals: a randomized trial

Background: Human sleep is characterized by alternating cycles of non-rapid eye movement (NREM) and rapid eye movement (REM) sleep, with cardiovascular regulation differing across sleep stages. Sleep deprivation (SD) is prevalent in modern societies and can be associated with worsened cardiovascular outcomes. Previous research on SD has primarily focused on epidemiological concerns and the effects of total SD, while clinical data on the hemodynamic impact of selective SD during different sleep stages remain scarce. This study aimed to investigate the hemodynamic alterations in healthy volunteers undergoing acute selective SD of either REM or slow-wave sleep (SWS) under polysomnography guidance. Additionally, the cardiovascular stability of healthy individuals under selective SD and its potential correlation with cardiovascular diseases were examined. Methods: A total of 30 healthy volunteers (male:female ratio =1:1; age 26.27±4.479 years) were enrolled in this study. Each participant underwent a 3-day experimental protocol: the first night involved normal sleep, the second night selective SD (either SWS or REM), and the third night recovery sleep. After an initial night of normal sleep, participants were randomly assigned to either the REMSD group (n=15) or the SWSSD group (n=15). During the SD night, participants were repeatedly awakened during REM or SWS sleep, with a total of three full-night deprivations. Hemodynamic parameters were recorded synchronously during SD interventions, with measurements taken 5 minutes before and after the first SD event, as well as before sleep onset and upon awakening. The hemodynamic parameters assessed included heart rate (), stroke volume index, cardiac index, cardiac power index, total peripheral resistance index, systolic blood pressure, and diastolic blood pressure. Results: In the SWSSD group, after SD, the heart rate significantly increased, while stroke volume index decreased (t=–4.37 to 2.21; P<0.05), whereas cardiac index, cardiac power index, and total peripheral resistance index showed no significant changes (P>0.05). In the REMSD group, heart rate, cardiac index, and cardiac power index increased, while total peripheral resistance index decreased (t=–5.91 to 2.39; P<0.05), with no significant changes in stroke volume index (P>0.05). Additionally, both groups had a significantly higher post deprivation DBP than a pre-SD diastolic blood pressure (t=–2.660; P<0.05). Conclusions: Healthy individuals demonstrated resilience to minor hemodynamic fluctuations. However, abrupt awakening from SWS could elevate the risk of cardiovascular events. Since REM sleep is associated with heightened sympathetic nervous system activity as compared to NREM sleep, selective REMSD may exacerbate cardiovascular physiological vulnerability during SD.