Benefits of ambulatory blood pressure monitoring in the design of antihypertensive drug trials.

REVIEW IN DEPTH: Ambulatory blood pressure monitoring (ABPM) offers substantial advantages over conventional clinic measurement in the assessment of antihypertensive agents. There is a greater reproducibility of an average blood pressure taken from multiple readings,s and in the setting of a clinical trial this translates into increased precision of the assessment of mean antihypertensive effect. The temporal profile of blood pressure and the antihypertensive effect of an agent can be studied directly, and times of the day of particular clinical importance, such as the end of the dosing period and the early morning period, can be studied more easily than for conventional blood pressure measurement. ABPM reduces the size of any placebo effect on blood pressure to very low values, and it can be used to exclude white-coat hypertensives from clinical trials, thereby reducing the noise in a clinical trial. The role of ABPM in drug evaluation looks set to increase further with new developments in blood pressure measurement technology.