Significance of blood pressure self-measurement as compared with office blood pressure measurement and ambulatory 24-hour blood pressure measurement in pharmacological studies.

With the increasing use of blood pressure self-measurement in pharmacological studies, the question arises as to whether this method can replace office blood pressure measurement or ambulatory 24-h blood pressure measurement for testing and comparing the efficacy of antihypertensives. Ambulatory 24-h blood pressure measurement or self-measurement available for analysis can be obtained in 70 to 90% of patients. Self-measurement shows a better correlation with the prognostically relevant ambulatory 24-h blood pressure measurement than office blood pressure measurement for appraising the antihypertensive effect. Although similar antihypertensive effects were found for ambulatory 24-h blood pressure measurement and self-measurement in the group comparison, substantial discrepancies can be observed in the individual patient owing to the different nature of these two methods of measurement. Both ambulatory 24-h blood pressure measurement and self-measurement are superior to office blood pressure measurement in terms of their reproducibility. This increases the sensitivity of clinical studies and reduces the number of cases required. Owing to the white-coat effect, variable compliance and drug holidays and their effects on the efficacy of antihypertensive medication are not detected by office blood pressure measurement and ambulatory 24-h blood pressure measurement. Self-measurement detects drug holidays, which are reflected in an increase of the blood pressure measurement values, and per se promotes compliance. Self-measurements and ambulatory 24-h measurements in pharmacological studies must be regarded as complementary, so that it is appropriate to use both methods whenever possible. Data management, data analysis and monitoring in pharmacological studies are facilitated by instruments with automatic data storage which allows telemonitoring.