STUDY OF THE INTERVAL TO RECORD THE AMBUL ATORY BLOOD-PRESSURE MONITORING

BACKGROUND: Ambulatory blood pressure monitoring (ABPM) throughout 24 hours has been introduced for clinical practice, improving the diagnos is and treatment of hypertension. However, there is not an agreement c oncerning how often the blood pressure have to be measured. SUBJECTS A ND METHODS: An ABPM was performed in 29 normotensive and hypertensive subjects (16-73 years) throughout 24 hours recording the blood pressur e every 15 minutes. The average of systolic and diastolic blood pressu re of the diurnal and nocturnal periods of the interval of 15 minutes, were compared with the two intervals of 30 minutes and the four of 60 minutes, according to Bland and Altman method. RESULTS: Between 90% a nd 100% of the differences of the interval 15 minutes versus 30 minute s, and 15 minutes versus 60 minutes, were within +2 and -2 standard de viation of the mean. However, only between 95% and 100% of the differe nces of the intervals 15 minutes versus 30 minutes were within the lim its of agreement for systolic and diastolic blood pressure in the noct urnal period. CONCLUSIONS: A clinical satisfactory information using A BPM can be obtained monitorizing the blood pressure every 15 minutes d uring the day and 30 minutes at night.