Office blood pressure and 24-hour ambulatory blood pressure measurements: high proportion of disagreement in resistant hypertension.
OBJECTIVE
To evaluate the accuracy and quantify the agreement between office blood pressure (BP) and daytime ambulatory BP monitoring in the assessment of BP control of patients with a clinical diagnosis of resistant hypertension.


METHODS
Office BP measurements were done in a cohort of 228 true resistant (TR) or white-coat resistant (WCR) hypertensives classified by ambulatory BP in a hypertension clinic in Rio de Janeiro in this validity study. The agreement between the daytime ambulatory BP and office BP was analyzed using the graphic methods of Altman -- Bland and survival -- agreement plots.


RESULTS
The likelihood ratio of a positive test result of office BP was 1.99 for the assessment of uncontrolled BP in TR patients and 1.05 for the WCR hypertensive patients. The Altman and Bland plot showed a significant difference between the two methods, and the presence of a fixed and a proportional bias. The survival-agreement plot showed that a tolerance limit of 20 mm Hg of difference between systolic office BP and systolic daytime ambulatory BP would generate a proportion of disagreement equal to 57.5%.


CONCLUSIONS
The office BP is still an important tool to monitor BP control of patients with TR hypertension, whereas the monitoring of patients with WCR hypertension requires ambulatory BP.
Rodrigues
Cláudia Soares
CS
Institute of Community Health (IESC), Federal University of Rio de Janeiro, Brazil.
Bloch
Katia Vergetti
KV
da Rocha Nogueira
Armando
A
D000368:Aged; D000959:Antihypertensive Agents / Q000627:therapeutic use; D001794:Blood Pressure / Q000187:drug effects; D001795:Blood Pressure Determination / Q000379:methods*; D018660:Blood Pressure Monitoring, Ambulatory; D004351:Drug Resistance; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D006973:Hypertension / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D008297:Male; D008875:Middle Aged
D000959:Antihypertensive Agents