Does a restricted sleep regimen alter ambulatory blood pressure in normotensive subjects?
Sleep deprivation during the first part of the night alters blood pressure and heart rate patterns, potentially due to sympathetic activation upon awakening.
The influence of sleep deprivation during the first part of the night on 24-h ambulatory blood pressure monitoring (ABPM) was studied in 18 normotensive subjects. They underwent two ABPM, one week apart: during the first, they slept from 11 PM to 7 AM, and during the second, from 2 AM to 7 AM. The main differences were observed at dawn, before awakening, when SBP and DBP significantly decreased (P < .01) in the restricted sleep regimen, and during the morning after the recovery sleep, when SBP and HR significantly increased (P < .05). The explanation for these findings is not obvious. We suppose that the decrease in SBP and DBP at dawn might be due to a reorganization of the sleep phases in the restricted sleep regimen, whereas the increase in SBP and HR after awakening might be due to a greater sympathetic activation, as though sleep deprivation was a stressful condition.
Paola Lusardi (Wed,) studied this question.