Physician-authored summaries and commentary on the most important medical research, provided by the NEJM Group, a division of the Massachusetts Medical Society.
© Massachusetts Medical SocietyMay 2025
Long and short protocols of multiple ‘unattended’ office BP measurements correlated with 24-hour ambulatory monitoring.
Measuring blood pressure (BP) accurately requires time and space – two precious commodities in a busy clinical practice. Automated devices that can measure BP at specified intervals with a patient alone in a quiet location (‘unattended’ BP measurement) provide accurate measurements while staff tend to other tasks. In this single-centre study, researchers in a Boston hypertension clinic used an unattended automated device* to compare delay times (3 vs 5 minutes for first measurement after clinic staff leave the room) and intervals between three consecutive measurements (30 vs 60 seconds); all patients had undergone 24-hour ambulatory BP monitoring a few days previously.
The longest protocol (5-minute delay, 60-second intervals) and the shortest protocol (3-minute delay, 30-second intervals) were tested in 67 and 44 patients, respectively. The average of each patient’s three readings were similar (mean, about 131/78 mmHg) and both protocols correlated closely with daytime average BP from 24-hour ambulatory monitoring.
Comment: A shorter, more efficient protocol was as accurate as a longer protocol in approximating out-of-office ambulatory BP. In my previous primary care practice, we used an unattended automated device selectively (e.g. when patients’ initial attended BP was higher than expected) and found it helpful. Whether this study’s findings can be extrapolated to delays and intervals when multiple BP readings are taken directly by clinical staff is unclear. Jennifer Cluett, MD, is an author of this study and a Contributing Editor for NEJM Journal Watch General Medicine.
Dr Cluett was not involved in selecting or summarising this paper for Journal Watch.
*An Omron HEM907XL was used in this study; other options include the Microlife Watch BP Office or BpTRU device.
Allan S. Brett, MD, Clinical Professor of Medicine, University of Colorado School of Medicine, Aurora, USA.
Lynn-Green EE, et al. Clinical impact of 3- vs. 5-minute delay and 30- vs. 60-second intervals on unattended automated office blood pressure measurements. Am J Hypertens 2025; 38: 168-177.
This summary is taken from the following Journal Watch titles: General Medicine, Ambulatory Medicine, Hospital Medicine, Neurology.