Blood Pressure Measurement Device, Number and Timing of Visits, and Intra-Individual Visit-to-Visit Variability of Blood Pressure
Article first published online: 9 OCT 2012
© 2012 Wiley Periodicals, Inc.
The Journal of Clinical Hypertension
Volume 14, Issue 11, pages 744–750, November 2012
How to Cite
Levitan, E. B., Kaciroti, N., Oparil, S., Julius, S. and Muntner, P. (2012), Blood Pressure Measurement Device, Number and Timing of Visits, and Intra-Individual Visit-to-Visit Variability of Blood Pressure. The Journal of Clinical Hypertension, 14: 744–750. doi: 10.1111/jch.12005
- Issue published online: 5 NOV 2012
- Article first published online: 9 OCT 2012
- Manuscript received: April 25, 2012; revised: June 20, 2012; accepted: July 14, 2012
J Clin Hypertens (Greenwich). 2012;14:744–750. ©2012 Wiley Periodicals, Inc.
Visit-to-visit variability (VVV) of blood pressure is associated with cardiovascular disease. The authors examined the effects of visit number and timing and automated or manual measurement device on VVV in the placebo arm of the Trial of Preventing Hypertension (TROPHY) (N=225) and simulations. VVV was assessed using intra-individual standard deviation (SD), range, maximum, coefficient of variation, successive variation, and average real variability of systolic blood pressure. VVV increased with number of visits used to calculate it in the TROPHY population (P for trend <.05 for all metrics) and simulations. Using consecutive visits in TROPHY, average SD was 5.6 mm Hg from 3 visits, 6.8 mm Hg from 7 visits, and 7.7 mm Hg from 18 visits. When 7 visits were spread out across 4 years, the average SD was higher (7.5 mm Hg) than when visits were consecutive over 18 months (P<.001). SD was higher using a single blood pressure measurement per visit (compared with the mean of 3 measurements per visit P<.001) and with automated vs manual devices (P<.001). In summary, number and timing of visits and device used to measure blood pressure influence VVV and need to be considered when designing, interpreting, and comparing studies.