Reproducibility of ambulatory blood pressure load.

Twenty-two hypertensive patients were monitored during two separate drug-free occasions with a Del Mar Avionics ambulatory device. Blood pressure loads (percentage of systolic and diastolic readings more than 140 and 90 mmHg, respectively) and mean BP were measured both to determine their reproducibility and to examine how they correlate with each other. The systolic and diastolic mean awake BPs for day 1 and day 2 were 140/93 mmHg and 140/91 mmHg, respectively, and BP loads were 45%/55% and 43%/54%. Moreover, mean BP loads correlated highly (r = 0.93) with mean BP values taken on the same day. Both ambulatory mean SBP and BP load were highly reproducible (r = 0.87 and 0.80, respectively, during the awake hours), and mean DBP and load were fairly reproducible (r = 0.59 and 0.39, respectively, during the awake hours). Clinically, however, both were consistent from day 1 to day 2. Mean and individual standard deviations also were reproducible for both systolic and diastolic pressures and loads.