EFFECTS OF A RESTRICTED SLEEP REGIMEN ON AMBULATORY BLOOD-PRESSURE MONITORING IN NORMOTENSIVE SUBJECTS

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 awak ening, when SEP and DBP significantly decreased (P < .01) in the restr icted sleep regimen, and during the morning after the recovery sleep, when SEP and HR significantly increased (P < .05). The explanation for these findings is not obvious. We suppose that the decrease in SEP an d DBP at dawn might be due to a reorganization of the sleep phases in the restricted sleep regimen, whereas the increase in SEP and HR after awakening might be due to a greater sympathetic activation, as though sleep deprivation was a stressful condition.