LAUSR

Objective: Automated office blood pressure (AOBP), measured in the absence of health care professionals, may eliminate white-coat effect. In the SPRINT study, blood pressure was measured with this method, and therefore, it is important to study its relationships to manually measured office blood pressure (OBP) which is crucial for clinical decision making as it was used in the vast majority of other prospective studies in hypertension. Design and method: Stable treated hypertensive subjects were included in this study which was performed in six Czech hypertension centres. AOBP was measured with the BPTru device (six measurements, average of 2nd to 6th measurement is considered); after AOBP, blood pressure (BP) was measured six times in the office (three times with auscultatory method by the physician followed by three oscilometric measurements). 24-hour ambulatory BP monitoring (ABPM) was performed within one week from the clinical visit. Results: Data on 191 subjects aged 64 ± 12 years with OBP 127.3 ± 12.2/77.5 ± 10.0 mm Hg are reported. AOBP was by 9.6 ± 19.2/3.2 ± 12.6 mm Hg lower than OBP and the difference was relatively homogeneous in all the centres. The AOBP-OBP difference was independent of age, number of antihypertensive drugs, presence of diabetes, lipid disorders or kidney disease; the interval from the morning drug intake had no influence either. We further compared the 4th to 6th BPTru measurement and 4th to 6th OBP measurement (i.e., only oscilometric measurements without and with presence of physician); it was 8.0/2.0 mm Hg. 24-hour mean BP was by 4.2/3.4 mm Hg lower than OBP and by 4.3/0.5 mm Hg higher than AOBP; the correlation coefficients of 24-hour mean BP with OBP and with AOBP did not differ (p for difference >0.10). Conclusions: AOBP gives comparable results in different clinical centres and thus, it can be introduced in clinical practice as a supplementary method to classic OBP. AOBP values are systematically lower than classic OBPand this phenomenon may partly explain the SPRINT results. Interindividual variability of the AOBP-OBP difference is large. The prediction of ABPM by AOBP is not better than by OBP.