Ambulatory blood pressure normalcy: the PAMELA Study.

Although ambulatory blood pressure monitoring is gaining in popularity, it still has important limitations in clinical use, particularly for the definition and diagnosis of hypertension. Various attempts have been made to calculate 'normal' or 'reference' values for ambulatory blood pressure, mostly by 24-h non-invasive monitoring in groups of 'normal' subjects. The most appropriate approach, however, is to compare 24-h ambulatory blood pressure values and casual or clinic blood pressure values in a random sample of a suitably large population. The PAMELA Study has been planned to obtain an epidemiological evaluation of 24-h ambulatory blood pressure values, and its design is described here. In the city of Monza, 2400 subjects aged between 25 and 64 years have been randomly selected according to World Health Organization Monitoring Cardiovascular Diseases (WHO-MONICA) project criteria within sex and age strata. In these subjects, clinic blood pressure, random-zero blood pressure, ambulatory blood pressure (24-h monitoring with SpaceLabs 90207; Redmond, Washington, USA), home blood pressure, electrocardiographic and echocardiographic indices, cardiovascular risk factors and psychological variables are being measured.