A Comparison of Casual In-Clinic Blood Pressure Measurements to Standardized Guideline-Concordant Measurements in Severely Obese Individuals

Abstract

Background/Objectives. The objective of this study was to compare casual BP taken in a bariatric clinic to standardized guideline-concordant BP. Subjects/Methods. A cross sectional analysis was performed using baseline data from a weight management trial. Patients were recruited from a Canadian bariatric care program. Standardized BP was performed using a Watch BP oscillometric device. Casual in-clinic BP single readings, taken using a Welch Allyn oscillometric device, were chart-abstracted. Paired t-tests, Bland-Altman plots, and Pearson's correlations were used for analysis. Results. Data from 134 patients were analyzed. Mean age was 41.5 ± 8.9 y, mean BMI was 46.8 ± 6.5 kg/m2, and 40 (30%) had prior hypertension. Mean casual in-clinic BP was 128.8 ± 14.1/81.6 ± 9.9 mmHg and mean standardized BP was 133.2 ± 15.0/82.0 ± 10.3 mmHg (difference of −4.3 ± 12.0 for systolic (p < 0.0001) and −0.4 ± 10.0 mmHg for diastolic BP (p = 0.6)). Pearson's coefficients were 0.66 (p < 0.0001) for SBP and 0.50 (p < 0.0001) for DBP. 28.4% of casual versus 26.9% of standardized measurements were ≥140/90 mmHg (p < 0.0001). Conclusion. In this bariatric clinic, casual BP was unexpectedly lower than standardized BP. This could potentially lead to the underdiagnosis of hypertension.

Variation between pragmatic and standardised blood pressure measurements in a Nigerian primary care clinic

“…Similar to this study, a previous Canadian study that compared casual in-clinic BP measurements to standardised BP measurements among severely obese patients in a bariatric clinic also found that casual in-clinic BP measurements were, on average, lower than standardised measurements. 18 Unlike the index study and the Canadian study, the previous studies on this topic, however, reported contrary conclusions; that is, usual-care BP measurements were higher than standardised measurements. 7,8,19,20 A South African study showed that the mean usual-care SBP and DBP were significantly higher than mean guidelineconcordant SBP and DBP by 10.7 mmHg and 3 mmHg, respectively.…”

“…The potential explanation for the observed difference in findings between the index study or Canadian study and previous studies 7,8,19,20 concerning the variation between usual-care and guideline-concordant BP can be ascribed to the different BP measurement protocol that was used in the guideline-concordant measurement protocol. While our study and the Canadian study 18 employed dual-arm BP measurement and used the arm with higher reading for the guideline-concordant BP, the previous studies 7,8,19,20 used the readings from a single arm as the guideline-concordant value. The use of a single arm for measuring guideline-concordant BP in the previous studies 7,8,19,20 is not in conformity with BP measurement guidelines that stipulated dual-arm BP measurements at the initial visit and subsequent measurement of BP in the arm with higher reading.…”

Comparability of two commonly used automated office blood pressure devices in the severely obese

“…Details are available elsewhere (NCT 01860131) [2,7]. The University of Alberta Research Ethics Board approved the study protocol and informed consent was obtained from all participants.…”

“…Much of the increase in cardiovascular risk found in severe obesity is mediated through elevated blood pressure (BP), which is present in about two-thirds of severely obese patients [2].…”