Blood pressure measurement: differences between arm side, sitting and supine position and between consecutive measurements

A Kluttig; D Tiller; B Schumann; O Kuss; K Greiser; K Werdan; J Haerting

doi:10.1055/s-0030-1266407

Das Gesundheitswesen, Table of Contents

Blood pressure measurement: differences between arm side, sitting and supine position and between consecutive measurements

A Kluttig ¹, D Tiller ¹, B Schumann ¹, O Kuss ¹, K Greiser ², K Werdan ¹, J Haerting ¹

¹Martin-Luther-Universität Halle-Wittenberg, Halle (Saale)
²Deutsches Krebsforschungszentrum, Heidelberg

Abstract

Background: High blood pressure (BP) is an established risk factor for cardiovascular disease. However, BP measurement conditions in epidemiological studies vary, leading to different estimates of hypertension frequencies. The aim of the study was to evaluate the dependence of BP estimates on different measurement conditions. Methods: This analysis uses data of 1778 participants (45–83 years) of the baseline investigation of the CARLA study. BP measurements using oscillometric devices included three sitting measurements at the left arm, one simultaneous supine measurement at both arms, and three supine measurements at the arm with the higher BP. We calculated means and 95% confidence intervals of differences between measurements and used linear regression to evaluate determinants of BP differences. Furthermore, we assessed the dependence of the prevalence of high BP (≥140/90mmHg) on the choice of BP measures used. Results: Mean diastolic BP (DPB) was slightly higher on left arm (mean DBP difference=0.98mmHg) whereas no differences were observed in systolic BP (SBP). Sitting SBP and DBP were higher than the corresponding supine BP (mean SBP difference=4.02mmHg; DBP=2.97mmHg). The BP difference by body position depends strongly on age and BP. Mean sitting and supine BP declined from first to second and second to third measurement by SBP=1.64 (sitting)/1.64 (supine) and 1.29/0.66 and DBP=0.51/0.94 and 0.21/0.33mmHg, respectively. The degree of BP decline depends on age, BP and BMI. The highest prevalence of high BP was found by using the first sitting measurement (63.60%), the lowest by using the third supine measurement (47.11%). Conclusion: Measured BP strongly depends on posture, number and combination of subsequent BP readings. BP measurements should only be compared between studies applying equal measurements conditions. The first BP measurement should not be used to define hypertension since it overestimates mean BP.