ESTIMATES OF BLOOD-PRESSURE VARIABILITY IN ADOLESCENTS USING AN AUTOMATIC BLOOD-PRESSURE MEASURING DEVICE

Knowledge of BP variability is important for BP screening and for the design of studies with BP as an outcome. We calculated estimates of th e between-visit and within-visit variances from data obtained using an automated BP device (Dinamap) in 776 students, aged 13-17 years, in t he Exeter-Andover Project. Each subject had his or her BP measured thr ee times per visit at up to 24 weekly visits. We compared these estima tes of variance with those published for adolescents using a standard mercury sphygmomanometer. For subjects measured using the Dinamap, the between-visit variance was greater for SBP and the within-visit varia nce for both pressures was almost three times greater than for subject s measured with the standard instrument.