1. LONG TERM BLOOD PRESSURE MONITORING J. Dušek 1, B. Fišer 1, J. Siegelová 1, P. Vank 1, G. Cornelissen 2, F. Halberg 2 1 Masaryk University, Brno 2 Halberg Chronobiology Center, University of Minnesota, Minneapolis, MN, USA

2. AIM OF THE STUDY is comparison between casual blood pressure measurements and 7-day blood pressure monitoring.

3. METHODS Ninety- one subjects without antihypertensive therapy (age between 20 and 80 years) were recruited for 7-day ambulatory BP monitoring (Collins Japan).

4. METHODS The obtained data were fitted with sinusoid curve (wave length 24 hours) by the least square method and mean value, so called MESOR (M) was determined.

6. METHODS The data of M of systolic blood pressure and diastolic blood pressure were compared with the values of one measurement at 10 a.m. (representative of casual blood pressure measurement). Further we compared M with mean values of 7 days 10 a.m. measurements.

8. RESULTS

11. The comparison of M with one 10 a.m. value of the 4 day of the monitoring revealed correlation (SBP: r=0.61, DBP: r=0.70) but the difference between measured values and expected values was in 70 % subjects higher than 6 mmHg of SBP. The corresponding proportion of subjects for DBP was 49 %. This indicates the low reliability of one measurement.

14. Using the 7 days mean 10 a.m. values the reliability increased (SBP: r=0.84, DBP: r=0.85) but despite the high correlation the difference higher than 6 mmHg was found in 32 % subjects (SBP), respective in 19 % (DBP).

15. CONCLUSION Our results clearly indicate the advantage of the long term blood pressure monitoring over casual blood pressure measurement for the blood pressure evaluation. Support: MSM0021622402