The role of ambulatory blood pressure monitoring in evaluating hypertensive patients and their treatment.

Clinical blood pressure often does not permit estimation of ambulatory blood pressure levels which may be lower than, identical to or higher than office pressure. By providing a substantial number of blood pressure values, ambulatory monitoring decreases subject variability and greatly increases the accuracy of blood pressure measurements. This technique is, therefore, attractive for determining hypertensive patients who would benefit from treatment. Moreover, ambulatory blood pressure measurements correlate well with target organ damage and appear to be a more potent predictor of cardiovascular morbidity and mortality than causal blood pressure. In recent years, ambulatory blood pressure monitoring has proved to be more reliable than measurements in a physician's office when evaluating the efficacy of antihypertensive drugs. It may confirm a fall in blood pressure demonstrated by office measurements and may give valuable information about the antihypertensive effect during specific situations, such as a stressful work setting. Furthermore, ambulatory monitoring is a useful tool for assessing the duration of antihypertensive drug effects. This technique can help to determine whether a once-daily regimen provides 24 h antihypertensive efficacy. Thus, ambulatory blood pressure monitoring is useful in identifying genuinely hypertensive patients who would benefit from treatment, as well as the effects and duration of antihypertensive medications.