How many measurements are needed to estimate blood pressure variability without loss of prognostic information?

Authors

Luis J. Mena
Gladys E. Maestre, The University of Texas Rio Grande ValleyFollow
Tine W. Hansen
Lutgarde Thijs
Yanping Liu
José Boggia
Yan Li
Masahiro Kanai
Kristina Björklund-Bodegård
Takayoshi Ohkubo

Document Type

Article

Publication Date

1-2014

Abstract

BACKGROUND

Average real variability (ARV) is a recently proposed index for short-term blood pressure (BP) variability. We aimed to determine the minimum number of BP readings required to compute ARV without loss of prognostic information.

METHODS

ARV was calculated from a discovery dataset that included 24-hour ambulatory BP measurements for 1,254 residents (mean age = 56.6 years; 43.5% women) of Copenhagen, Denmark. Concordance between ARV from full (≥80 BP readings) and randomly reduced 24-hour BP recordings was examined, as was prognostic accuracy. A test dataset that included 5,353 subjects (mean age = 54.0 years; 45.6% women) with at least 48 BP measurements from 11 randomly recruited population cohorts was used to validate the results.

RESULTS

In the discovery dataset, a minimum of 48 BP readings allowed an accurate assessment of the association between cardiovascular risk and ARV. In the test dataset, over 10.2 years (median), 806 participants died (335 cardiovascular deaths, 206 cardiac deaths) and 696 experienced a major fatal or nonfatal cardiovascular event. Standardized multivariable-adjusted hazard ratios (HRs) were computed for associations between outcome and BP variability. Higher diastolic ARV in 24-hour ambulatory BP recordings predicted (P < 0.01) total (HR = 1.12), cardiovascular (HR = 1.19), and cardiac (HR = 1.19) mortality and fatal combined with nonfatal cerebrovascular events (HR = 1.16). Higher systolic ARV in 24-hour ambulatory BP recordings predicted (P < 0.01) total (HR = 1.12), cardiovascular (HR = 1.17), and cardiac (HR = 1.24) mortality.

CONCLUSIONS

Forty-eight BP readings over 24 hours were observed to be adequate to compute ARV without meaningful loss of prognostic information.

Comments

Copyright © American Journal of Hypertension, Ltd 2013. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Recommended Citation

Mena, L. J., Maestre, G. E., Hansen, T. W., Thijs, L., Liu, Y., Boggia, J., Li, Y., Kikuya, M., Björklund-Bodegård, K., Ohkubo, T., Jeppesen, J., Torp-Pedersen, C., Dolan, E., Kuznetsova, T., Stolarz-Skrzypek, K., Tikhonoff, V., Malyutina, S., Casiglia, E., Nikitin, Y., Lind, L., … International Database on Ambulatory Blood Pressure in Relation to Cardiovascular Outcomes (IDACO) Investigators (2014). How many measurements are needed to estimate blood pressure variability without loss of prognostic information?. American journal of hypertension, 27(1), 46–55. https://doi.org/10.1093/ajh/hpt142

Publication Title

American journal of hypertension

DOI

10.1093/ajh/hpt142

Academic Level

faculty

Mentor/PI Department

Office of Human Genetics