Ambulatory blood pressure monitoring use in hypertension research and clinical practice.

In his article on blood pressure measurement by sphygmomanometry published in 1897 in the Gazzetta Medica di Torino,' Riva Rocci wrote the following: "Blood pressure is acted upon, in a temporary but pronounced fashion, by the state of 'psychic' excitation of the patient. It is enough that the patient is spoken to, that he is invited to read, that he is even looked at suddenly, or that a sudden and even far noise strikes him (e.g., a carriage passing by in the outside street) that his blood pressure raises, and not at all to the same extent in all patients. This emotional reaction may be useful in psychiatry, but in other disciplines these blood pressure rises represent an inconvenience, and it is therefore necessary for the patient to be put in an environment as quiet as possible. . . . Furthermore, because even the application of the instrument causes a temporary blood pressure rise, it is necessary to take not only one but several consecutive blood pressures spaced by 3or 5-minute intervals until a constant value is measured. This value, however, is not always the minimal value.. . . It should not be necessary to add that it will not be proper to compare data unless obtained in identical conditions or environment, position, time of day, distance from meals, wakefulness, etc. This remark is certainly superfluous for the investigators, but it may be useful to practitioners whose hurry may in this case result in a waste rather than a gain of time."