Abstract P011: Usefulness Of Standing Office Blood Pressure In Detecting Hypertension In Untreated Adults

Abstract

Clinical guidelines recommend office blood pressures (BP) to be taken in a seated position. However, the accuracy of standing BP measurements for diagnosing hypertension (HTN) has not been investigated. We assessed BP in both seated and standing positions in 125 healthy adults not on anti-HTN medications. HTN was defined by 24-hour ambulatory SBP/DBP of ≥ 125/75 mmHg. Area under receiver operator characteristic curve (AUROC) was calculated to determine accuracy of seated and standing BP in diagnosing HTN. Bayes factor (BF) was used to assess the significance of the difference between AUROC of seated and standing BP. Sensitivity and specificity of standing BP in diagnosing HTN was derived using cut-off points derived from Youden’s Index. Our cohort’s mean age was 49 ± 17 years, with 62% female (77 of 125), and 24% Black (30 of 125). Prevalence of HTN was 33.6% (42 of 125). Sensitivity and specificity of seated SBP was 43% and 92%, respectively. Optimal cutoffs selected by Youden’s index for standing SBP/DBP was 124/81 mmHg. Sensitivity and specificity of standing SBP was 74% and 65%, respectively. The AUROC of standing SBP was significantly higher than seated SBP (BF =11.8), when HTN was defined as 24-Hr SBP ≥ 125 mmHg (Fig 1). Similarly, when HTN was defined as 24-Hr DBP ≥ 75 mmHg or daytime DBP ≥ 80 mmHg, the AUROC of standing DBP was higher than seated DBP (all BF >3). The addition of standing to seated BP improved HTN detection than seated BP alone based on 24-Hr SBP/DBP ≥ 125/75 mmHg or daytime SBP/DBP ≥ 130/80 mmHg (all BF >3). In conclusion, standing office BPs both alone and in combination with seated BPs, outperformed seated BPs in diagnosing hypertension in untreated adults.