BLOOD-PRESSURE EVALUATION BY NONINVASIVE AND TRADITIONAL METHODS - CONSISTENCIES AND DISCREPANCIES AMONG PHOTOPLETHYSMOMANOMETRY, OFFICE SPHYGMOMANOMETRY, AND AMBULATORY MONITORING - EFFECTS OF BLOOD-PRESSURE MEASUREMENT

Three hundred eight outpatients referred for hypertension were studied . A continuous beat-to-beat noninvasive recording (Finapres) of blood pressure evaluated the blood pressure increase (9 mm Hg systolic and 4 mm Hg diastolic) induced by office sphygmomanometry. Thereafter, pati ents underwent a 24-h ambulatory blood pressure monitoring. The evalua tion against Finapres showed that office sphygmomanometry overestimate s the systolic blood pressure by 3 +/- 36 mm Hg (mean +/- 2 SD) and th e diastolic blood pressure by 15 +/- 25 mm Hg (mean +/- 2 SD). Blood p ressure monitoring showed similar discrepancies. On the basis of both monitoring (normalcy defined from a population of 550 normotensive sub jects) and office sphygmomanometry, patients were considered normotens ive, hypertensive (either untreated or under active drug treatment), w hite coat hypertensive (monitoring below the 95th percentile and sphyg momanometry more than 140/90 mm Hg, either untreated or under active d rug treatment), and reverse white coat patients (monitoring over the 9 5th percentile and sphygmomanometry less than 140/90 mm Hg). Patients showed different levels of alert reaction (the highest in white coat h ypertensive and the lowest in reverse white coat hypertensive patients ), and a similar increase in blood pressure induced by conventional sp hygmomanometry, During initial readings of ambulatory monitoring, bloo d pressure decreased from the first reading to the third reading. This decrease is related to the increase of blood pressure under sphygmoma nometry. Caution should be paid in interpreting results of sphygmomano metry (error level in the single patient as high as +/- 40 mm Hg), and interpreting and averaging results of the first hour of blood pressur e monitoring (variably affected by the alert reaction to the clinical environment).