a new study suggests.
Combining three standing and three seated BP measurements in the same visit may lead to a “quicker diagnosis and save people a trip back to the office,” Wanpen Vongpatanasin, MD, professor of internal medicine and director of the hypertension section, cardiology division, UT Southwestern Medical Center, Dallas, said in an interview.
The study was presented at the Hypertension Scientific Sessions, sponsored by the American Heart Association.
Practice changing?
Clinical guidelines recommend office BP be taken in a seated position for most patients.
However, research has suggested that the sensitivity of seated office BP in diagnosing hypertension is about 50%, with high specificity around 90% during a single visit, Dr. Vongpatanasin explained.
At the follow-up visit, however, the second office BP yielded higher sensitivity to 80% but specificity fell to 55%. Nevertheless, the accuracy of standing BP measurements for diagnosing hypertension has not been investigated.
In a cross-sectional study, Dr. Vongpatanasin and colleagues determined the accuracy of both seated and standing BP for diagnosing hypertension in a single visit in 125 healthy adults who had not had a previous diagnosis of hypertension and were not taking any BP medications. The cohort had a mean age of 49 years, 62% were women, and 24% were Black.
During each office visit, seated BP was measured three times, then standing BP was measured three times using an automated and validated device.
Average seated BP was 123/76 mm Hg and average standing BP was 126/80 mm Hg.
Of the 125 participants, 42 (34%) had hypertension, defined as 24-hour ambulatory systolic/diastolic BP (SBP/DBP) of ≥ 125/75 mm Hg.
The sensitivity and specificity of seated SBP for hypertension was 43% and 92%, respectively.
“Interestingly, with standing SBP, sensitivity was improved to 74% and specificity dropped to 65% – which is okay; you will have to confirm a positive test anyway and when screening for a common disease you’d rather have a high sensitivity rather than low sensitivity to pick it up in this case,” Dr. Vongpatanasin said.
The area under receiver operating characteristic curve (AUROC) of standing SBP was significantly higher than seated SBP (Bayes factor [BF] = 11.8) when hypertension was defined as 24-hour SBP ≥ 125 mm Hg.
Similarly, when hypertension was defined as 24-hour DBP ≥ 75 mm Hg or daytime DBP ≥ 80 mm Hg, the AUROC of standing DBP was higher than seated DBP (all BF > 3).
The addition of standing to seated BP improved detection of hypertension compared with seated BP alone based on 24-hour SBP/DBP ≥ 125/75 mm Hg or daytime SBP/DBP ≥ 130/80 mm Hg (all BF > 3).
“In our hypertension clinic, we always measure both seated and standing BP in all of our patients,” John Giacona, PA-C, a PhD candidate at UT Southwestern Medical Center and coauthor of the study, told this news organization,
Multiple readings most important
Reached for comment, Johanna Contreras, MD, a cardiologist at Mount Sinai Hospital in New York, noted that diagnosing hypertension is “difficult” and she agrees that multiple readings are important.
“I usually take at least two readings in two different visits before I tell the patient they have high blood pressure,” Dr. Contreras said in an interview.
Dr. Contreras said she takes blood pressure both seated and standing.
“I’m not sure standing versus seated makes a big difference. However, when the patient first comes into the office, it is really important to let them rest and calm down before taking the blood pressure,” she said.
The study had no commercial funding. The authors and Dr. Contreras have disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.