Ambulatory and home blood pressure normality: the Pamela Study

Ambulatory blood pressure monitoring (ABPM) is increasingly used in the clinical evaluation of hypertension. However, a number of limitations restrict its routine use. One of the limitations is a lack of definite conclusions about ambulatory blood pressure normality, because of the shortcomings of previous studies on this issue. In the present study we describe a survey from a large sample of subjects within the age range of 25-64 years. It was found that 24-h average systolic and diastolic blood pressures are markedly lower than clinic blood pressure, and for daytime average and home blood pressure as well. In addition, it was found that the clinic ambulatory or home blood pressure disparity is related to the baseline clinic blood pressure (i.e., it increases with increasing clinic blood pressure values) and that the three pressures (ambulatory, home, clinic) are closely related to each other, thereby allowing the application of correction factors to obtain information on ambulatory or home blood pressure normality. This results in an upper normality limit for 24-h average blood pressure and home blood pressure of around 120 mm Hg systolic and 77 mm Hg diastolic pressure.