LAUSR

Objective: Accurate and precise measurement of blood pressure [BP] is critical for both diagnostics and guiding clinical decisions in arterial hypertension. Unattended automated blood pressure measurement [UABPM] can simplify the measurement process, reducing human error and minimizing the white coat effect. The purpose of this study was to analyze the differences in BP between office attended [oABPM] and UABPM and examine their relation with the level of anxiety. Design and method: We conducted a prospective study in the group of 124 hypertensive outpatients (56 % female, mean age 55,3 ± 12,3 years). Each patient had been asked to fill out a health questionnaire and perform the State-Trait Anxiety Inventory, a standardized psychological questionnaire measuring level of anxiety. Afterward, BP was measured using two methods with random order: oABPM – after 5 minutes of rest 3 measurements in 1-minute intervals were taken by a doctor UABPM – after programming the device by a doctor, patient was left alone, after 5 minutes the device performed 3 measurements in 1-minute intervals. Differences in BP were compared using paired sample t-test. Correlation between differences and level of anxiety was nalysed using Pearson correlation coefficient. Results: In UABPM both systolic and diastolic BP values were significantly lower than in oABPM (4,19 ± 6,48 mmHg, p < 0,001 and 2,04 ± 3,34 mmHg, p < 0,001, respectively). These differences t were more pronounced in the group that had attended measurements taken first (5,98 ± 6,57 mmHg, p < 0,001 for systolic and 3,11 ± 3,52 mmHg, p < 0,001 for diastolic). In this group, significant correlation between systolic BP and level of anxiety was found (r = 0,27, p = 0,047). In multiple regression female sex (B = -4,62, p < 0,001 for systolic and -1,19, p = 0,042 for diastolic) and order of measurements (B = 3,63, p < 0,001 for systolic and 2,06, p < 0,001) for diastolic) were most significantly influencing BP differences between compared methods. Conclusions: Routine clinic measurements can overestimate BP values and the difference in oABPM and UABPM partly depends on the level of anxiety. Accurate BP measurement has important implications for treatment decisions like dose and/or drug escalation.