Accuracy of abbreviated protocols for unattended automated office blood pressure measurements, a retrospective study.
Level 4 - case-series / case-control
Retrospective single-center diagnostic and method-comparison study
PubMed 33720945 · doi:10.1371/journal.pone.0248586
What was done
In a retrospective single-center study, researchers evaluated 413 unattended automated office blood pressure measurement (AOBPM) sets from 210 patients (mean age 52 ± 16 years) collected over 14 months. The standard reference protocol (RefProt; 3 sequential measurements spaced 2 minutes apart after 5 minutes of rest) was compared against two shortened alternatives: the average of the first two measurements (ShortProtA) and the single first measurement (ShortProtB).
What was found
Mean blood pressures were 128.3/81.3 mmHg for RefProt, 128.4/81.4 mmHg for ShortProtA, and 128.8/81.4 mmHg for ShortProtB. Mean differences and limits of agreement compared to RefProt were -0.1 ± 4.2 / -0.1 ± 2.8 mmHg for ShortProtA and -0.5 ± 8.1 / -0.1 ± 5.3 mmHg for ShortProtB. For ShortProtA, 83% of systolic and 92% of diastolic readings were within 2 mmHg of RefProt (versus 67% and 82% for ShortProtB). Neither shortened protocol resulted in significant hypertensive reclassifications compared to RefProt (p-values ranging from 0.556 to 1.000).
Why it matters
Unattended automated office blood pressure measurement improves measurement consistency but is resource-intensive; reducing the protocol from three readings to two saves clinical time without meaningfully changing blood pressure estimates or hypertension classification.
Limits
The study is retrospective and limited to a single center. It compared shortened protocols only against the 3-measurement office average rather than assessing agreement with 24-hour ambulatory monitoring or hard cardiovascular outcomes.
Cited by
- context In the SPRINT trial blood pressure protocol, participants sat for 5 minutes without stimulation before having blood pressure measured, repeated for checks at 5, 10, and 15 minutes.