Limited reproducibility of hourly blood pressure values obtained by ambulatory blood pressure monitoring : implications for studies on antihypertensive drugs

Objective: To assess the reproducibility of average hourly blood pressure values obtained by 24-h non-invasive ambulatory monitoring, Patients: Fifteen outpatients with essential hypertension. In all subjects antihypertensive treatment was withdrawn for 4 weeks before and during the 4 weeks of the study. Methods: The 24-h blood pressure was monitored by a SpaceLabs 5300 device (four readings per hour during the day and three readings per hour during the night) twice, at a 4-week interval