Determination of ambulatory blood pressure control in treated patients with controlled office blood pressures

Office blood pressure measurement is the standard for assessing blood press ure control. Many patients, however, take their antihypertensive medication in the morning, so they are likely to have their office blood pressure mea sured during the maximal antihypertensive effect. It is therefore unknown w hether patients deemed by office blood pressure to be controlled do in fact have 24 h blood pressure control. The objectives of this study were to det ermine blood pressure control, including blood pressure control while the p atients were awake and during the first 6 h after awakening, by ambulatory brood pressure monitoring (ABPM) in treated hypertensive patients deemed by office blood pressure measurements to be controlled. A total of 103 patients on a stable antihypertensive regimen and deemed to be controlled in terms of office blood pressure values (mean office blood p ressure < 140/90 mmHg) were enrolled. Patients were stratified by cardiovas cular risk status and the number of antihypertensive medications that they were taking. Seventy-eight out of 103 participants successfully completed A BPM, The mean ambulatory blood pressure was greater than 135/85 mmHg and 14 0/90 mmHg while awake for 37% (95% confidence interval [CI] 26-48%) and 23% (95% CI 14-32%) of all patients respectively. Forty-eight per cent (95% CI 33 - 63%) of patients taking monotherapy versus 25% (95% CI 11-39%) of pat ients on multiple antihypertensive medications were uncontrolled (P = 0.039 ) using 135/ 85 mmHg as the reference value. Thirty-one per cent (95% CI, 1 7-44%) of patients on monotherapy versus 14% (95% CI 3-25%) of patients on multiple antihypertensive medication were uncontrolled (P = 0.064) using 14 0/90 mmHg instead. These results demonstrate that a high number of patients deemed by office blood pressure to be under control do not have adequate b lood pressure control based on ABPM. Blood Press Monit 5:263-269 (C) 2000 L ippincott Williams & Wilkins.