Superiority of ambulatory to physician blood pressure is not an artifact of differential measurement reliability.
BACKGROUND
Ambulatory blood pressure is a better predictor of target organ damage and the risk of adverse cardiovascular events than office measurements. Whether this is due to the greater reliability owing to the larger number of measurements that are usually taken using ambulatory monitoring, or the greater validity of these measurements independent of the number, remains controversial.


METHODS
We addressed this issue by comparing physician readings and ambulatory measurements as predictors of left ventricular mass index. The number of readings was controlled by using the average of three physician readings and randomly selecting three awake readings from a 24-h ambulatory recording.


RESULTS
In a multiple regression analysis that included both the ambulatory and physician blood pressure measurements, only the ambulatory systolic measurements significantly predicted left ventricular mass index (B=0.37, t=3.11, P=0.002); the coefficient for physician's systolic measurements was essentially zero (B=-0.01, t=-0.26, NS).


CONCLUSIONS
These findings suggest that the superiority of ambulatory blood pressure as a predictor of target organ damage, compared with physician measurements, cannot be adequately/fully explained by the impact of the larger number of measurements obtained with ambulatory monitoring.
Gerin
William
W
Department of Medicine, Columbia University/New York-Presbyterian Hospital, New York, NY 10032, USA. wg131@columbia.edu
Schwartz
Joseph E
JE
Devereux
Richard B
RB
Goyal
Tanya
T
Shimbo
Daichi
D
Ogedegbe
Gbenga
G
Rieckmann
Nina
N
Abraham
Dennis
D
Chaplin
William
W
Burg
Matthew
M
Jhulani
Juhee
J
Pickering
Thomas G
TG
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018660:Blood Pressure Monitoring, Ambulatory; D005260:Female; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D006973:Hypertension / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010820:Physicians; D015203:Reproducibility of Results