HOME BLOOD-PRESSURE - VARIABILITY, COMPARISON WITH OFFICE READINGS AND PROPOSAL FOR REFERENCE VALUES

Purpose: A multicentre study was performed on 390 healthy subjects (21 0 male, 180 female) to evaluate home blood pressure versus office bloo d pressure. Methods: The patients, aged 20-59 years, not on antihypert ensive treatment, were not preselected by blood pressure levels. Blood pressure was measured in the doctor's office, using a mercury manomet er at the fifth, sixth and seventh minute of rest, and at home by self -measurement using a validated electronic oscillometric device at the fifth, sixth and seventh minute of rest, in the morning and evening, o n three consecutive days. Results: The analysis of office and home mea surements at the fifth, sixth and seventh minute of rest showed a sign ificant decrease in blood pressure, mostly between the fifth and sixth minute. There was no significant variation in home pressure over the three consecutive days of measurement. Blood pressures were significan tly higher in the evening than in the morning; the mean differences we re 3 mmHg for systolic and 1.5 mmHg for diastolic blood pressure. Comp ared with office blood pressure measurement, home measurement provided significantly lower systolic and diastolic blood pressure means. Of t he subjects, 78% showed a higher systolic and 69.9% a higher diastolic blood pressure with office measurement than with home measurement. Sy stolic and diastolic blood pressure differences were non-significantly higher for females than for males and did not differ with age. Conclu sions: The comparison of the office and home measurement distributions allowed us to propose reference values for home blood pressure measur ement. These were established by choosing blood pressure at the identi cal percentile for home measurement as we found for office measurement using the World Health Organization criteria (140/90 and 160/95 mmHg) . Using this approach, the upper limit for normotension by home measur ement would be 127/83 mmHg and for hypertension 147/86 mmHg. Although this approach has no prognostic value, it could be useful for the inte rpretation of home blood pressure.