The Role of Ambulatory Monitoring of the Blood Pressure for Assessment of Antihypertensive Agents

For many decades, the casual blood pressure (BP) has been the standard for assessing BP response to antihypertensive agents in clinical trials. Noninvasive ambulatory BP technology has improved vastly in the last 15 years and has been increasingly used in dose-response studies as well as efficacy trials. Through these studies we have learned that casual BP may not be representative of the average daily blood pressure, that it may be quite susceptible to observer bias, and that it may result in inaccurate calculation of the trough-to-peak ratio of an antihypertensive drug. Perhaps more importantly is that a large body of data now supports the superiority of average daily BP over that of the casual or clinic BP in predicting several indexes of hypertensive target organ damage. Thus, use of the ambulatory BP technique in antihypertensive trials yields BP data that are far less susceptible to improper diagnosis and are representative of the hypertensive burden that causes vascular disease.