The smoothness index of betaxolol hydrochloride in patients with newly diagnosed hypertension

Czech version

Authors: I. Řiháček; M. Souček; P. Fráňa
Authors‘ workplace: II. interní klinika Lékařské fakulty MU a FN u sv. Anny, Brno, přednosta doc. MUDr. Miroslav Souček, CSc.
Published in: Vnitř Lék 2007; 53(1): 25-30
Category: Original Contributions

Overview

Introduction:
24-hour ambulatory blood pressure monitoring (ABPM) has a higher predictive value for cardiovascular diseases than occasional blood pressure (BP) measurement with sphygmomanometer. ABPM allows for the assessment of 24-hour effect of drugs administered once a day using the smoothness index (SI) method.

Objective of work:
Find out the 24-hour effect of betaxolol hydrochloride administered once a day by determining the smoothness index.

Cohort and methodology:
Examination of 30 newly diagnosed hypertonics prior to and after 3-month treatment with betaxolol hydrochloride at an average dose of 15 mg once a day. BP measurement using sphygmomanometer and ABPM (SpaceLabs 90207) according to European Society for Hypertension criteria. Determining the smoothness index from individual average hourly changes in BP after treatment by dividing the hourly values average by standard deviation. Calculation of average SI from individual patient data with standard deviation and 95 % confidence interval (95 % CI).

Result:
The calculated SI value of betaxolol hydrochloride was 1.03 ± 0.65 (95 % CI, 0.80 to 1.26) and 1.27 ± 0.89 (95 % CI, 0.95 to 1.59) for systolic and diastolic BP, respectively.

Conclusion:
Average SI of betaxolol hydrochloride is higher than 1 when both systolic and diastolic BP is measured. Based on the above parameter, the monitored drug has a sufficient 24-hour effect and can be administered once a day.

Key words:
beta-blockers – betaxolol hydrochloride – smoothness index tenze

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