The evaluation of antihypertensive therapy using 24-h ambulatory monitoring technology.

Several specific features of ambulatory monitoring of the blood pressure have made it important in clinical trials that assess antihypertensive drug therapy. These include the removal of observer bias, improved short-term and long-term blood pressure reproducibility compared with clinic readings, elimination of the 'white-coat' effect during patient selection and the ability to assess the effects of long-acting once daily therapies on diurnal and nocturnal blood pressure. In this article, an overview of the utility of ambulatory blood pressure monitoring in clinical trials is provided, with specific examples that use data from recent studies of the newer compounds that block the renin-angiotensin system.