Analysis of 24-hour blood pressure data.

Blood pressure is not constant over the course of a 24-h period, but exhibits a predictable and characteristic rise and decline during the day. Although the general shape of this pattern is similar from patient to patient the knowledge of an individual's blood pressure at one or two points on this curve is of no predictive value in estimating the remainder of the curve. Since critical events are associated with both the maximum and minimum blood pressures that an experiences individual a characterization of this curve can be very important. The development of antihypertensive agents historically presumed that the reduction in blood pressure associated with therapy be would be, if not constant, at least adequate throughout the entire period. However, with the advent of less frequent dosing, the importance of assuring that blood pressure was adequately controlled over the 24-h period became important. This created interest in two basic types of comparisons. One is the comparison of dosing regimens e.g., com...