Factors that must be considered while solving the problem of adequate control of blood pressure

Many physicians still believe that single blood pressure (BP) measurements provide reliable information for diagnostic purposes and treatment decisions. However, already 40 years ago, long before ambulatory BP monitoring became available, it was recognized that such strategy is nearly equal to flipping a coin and may end up in over 40% of false diagnostic conclusions (Management Committee, Australian National Blood Pressure Study, 1980). Today we know much more about BP variability (BPV). Plenty of factors heavily influence BP (irrespective of the device doctors or patients are using to measure BP). Not only are BP values influenced at the time of measurement, BPV and circadian characteristics of BP have also been shown to be affected. A significant role is played not just by time of the day (circadian phase and amplitude) but also by rhythms of some other frequencies, for example, the 12-hour and about-weekly components. In addition, timing determines not only how high or how low blood pressure is at this very moment, but also the derivative parameters of its variability. The purpose of this mini review is to give a schematic but dense idea of why single measurements of blood pressure are not informative, and even often misleading. The presented information should be used primarily by general clinicians, cardiologists, as well as specialists involved in the development of telemedicine technologies and the concept of personalized medicine.