Ambulatory blood pressure monitoring and antihypertensive treatment.

Ambulatory blood pressure monitoring is becoming increasingly popular among clinicians and investigators because of its potential to overcome the well-known limitations inherent to conventional blood pressure measurement. This paper will focus on the use of this approach in the evaluation of antihypertensive treatment. It will be argued that due to lack of prognostic validity and high cost, ABPM should not be employed routinely in treating hypertensives. It should always be employed, however, for the evaluation of the efficacy of new hypertensive drugs for which its superiority over sphygmomanometry is indisputable. This is exemplified by the results of a recent multicenter, double-blind, parallel group study on the effect of verapamil SR 240 mg, enalapril 20 mg and nitrendipine 20 mg and placebo, all administered once a day for eight weeks. Compared to placebo, all drugs reduced 24-hour mean blood pressure sufficiently. The reduction was evident throughout the daytime but nighttime blood pressure was more effectively lowered by verapamil and enalapril than by nitrendipine, documenting a difference that was not visible by using conventional measurements.