Current guidelines recommend a 5-minute rest period before a blood pressure screening measurement, but that might not be necessary for all patients.
In a prospective crossover study, average differences in blood pressure measurements obtained after 0 or 2 minutes of rest were not significantly different than readings obtained after the recommended 5 minutes of rest in adults with systolic blood pressure (SBP) below 140 mm Hg.
“The average differences in BP by rest period were small, and BPs obtained after shorter rest periods were noninferior to those obtained after 5 minutes when SBP is below 140,” Tammy M. Brady, MD, PhD, Johns Hopkins University School of Medicine, Baltimore, told theheart.org | Medscape Cardiology.
“This suggests shorter rest times, even 0 minutes, may be reasonable for screening when the initial SBP is below 140,” said Brady.
She presented her research at the virtual American Heart Association (AHA) Hypertension 2020 Scientific Sessions.
A Challenging Recommendation
The 5-minute rest period is “challenging” to implement in busy clinical settings, Brady said. The researchers therefore set out to determine the effect of no rest and the effect of a shorter rest period (2 minutes) on blood pressure screening.
They recruited 113 adults (mean age, 55; 64% women, 74% Black) with SBP that ranged from below 115 mm Hg to above 145 mm Hg and with diastolic blood pressure that ranged from below 75 mm Hg to above 105 mm Hg. About one-quarter (28%) had SBP in the stage 2 hypertension range (at least 140 mm Hg).
They obtained four sets of automated BP measurements after 5, 2, or 0 minutes of rest. All participants had their BP measured after a second 5-minute rest period as their last measurement to estimate repeatability.
Overall, there was no significant difference in the average BP obtained at any of the rest periods.
After the first and second 5-minute rest period, BPs were 127.5/74.7 mm Hg and 127.0/75.6 mm Hg, respectively. After 2 and 0 minutes of rest, BPs were 126.8/73.7 mm Hg and 126.5/74.0 mm Hg.
When looking just at adults with SBP below 140 mm Hg, there was no more than an average difference of ±2 mm Hg between BPs obtained at the 5-minute resting periods, compared with the shorter resting periods.
However, in those with SBP below 140 mm Hg, BP values were significantly different (defined as more than ±2 mm Hg) with shorter rest periods, “suggesting that shorter rest periods were in fact inferior to resting for 5 minutes in these patients,” Brady told theheart.org | Medscape Cardiology.
More Efficient, Economic
“Economics play a significant role in blood pressure screenings, as clinics not as well-funded may find it especially challenging to implement a uniform, five-minute rest period before testing, which could ultimately reduce the number of patients able to be screened,” Brady added in a conference statement.
“While our study sample was small, a reasonable approach based on these findings would be to measure blood pressure after minimal-to-no rest, and then repeat the measurements after five minutes only if a patient is found to have elevated blood pressure,” she said.
Weighing in on the results, Karen A. Griffin, MD, who chairs the AHA Council on Hypertension, said that “reducing the rest period to screen an individual for hypertension may result in faster throughput in the clinic and confer a cost savings.”
“At the present time, in order to maintain the clinic flow, some clinics use a single, often times ‘nonrested’ BP measurement as a screen, reserving the 5-minute rest automated-office BP measurement for patients found to have an elevated screening BP,” noted Griffin, professor of medicine, Loyola University Medical Center, Maywood, Illinois.
“Nevertheless, even if limiting the use of automated-office BP to those who fail the initial screening BP, a cost savings would still be realized by reducing the currently recommended 5-minute rest to 2-minutes and have the most impact in very busy, less-well-funded clinics,” said Griffin.
She cautioned, however, that further studies in a larger population will be needed before making a change to current clinical practice guidelines.
The study had no specific funding. Brady and Griffin have no relevant disclosures.
Hypertension 2020 Scientific Sessions: Abstract P154. Presented September 10, 2020.