Abstract MP35: Automated Office Blood Pressures For Making A Diagnosis Of Hypertension And The Effect Of Attendance And Rest Time

Abstract

Context: Automated office blood pressure (AOBP) where three to five blood pressures (BP) are taken using an oscillometric device without an attendant in the room may decrease white coat effect. Objective: We evaluated the presence/absence of the attendant and varying amounts of rest time on BP; and the diagnostic performance of AOBP in making a new diagnosis of hypertension compared to daytime ambulatory blood pressure monitoring (ABPM). Methods: Participants included 130 adults aged 18-84 with no hypertension diagnosis or treatment and high BP ( > 140/90) prior to the study. Participants completing ABPM testing in the prior 24-hours were randomized either to Attended AOBP first, unattended second or; Unattended AOBP first, attended second . AOBP was subsequently performed twice, once after 5 minutes of rest and again after 15 minutes. Outcomes included within person difference between attended versus unattended BPs , and between 5 and 15 minutes of rest. Sensitivity and specificity of AOBP for making a new diagnosis of HTN was evaluated. Results: AOBP was significantly lower than mean daytime ABPM regardless of rest or attendance (systolic BP between -3.9 mmHg and diastolic BP -2.9 mm Hg lower). There were no significant within-person differences between AOBPs that were attended versus unattended (mean difference systolic 0.1 mmHg, CI -0.8, 1.1; diastolic 0.2 mmHg, CI -0.5, 0.8) or after five versus 15-minutes of rest (mean difference systolic -0.5 mmHg, CI -1.4, 0.5, diastolic 0.2 mmHg, CI -1.2, 0.0). Using daytime mean ABPM threshold of > 135/85, the sensitivity and specificity of AOBP for making a new diagnosis of hypertension was 71.0% and 54.1%. Conclusion: Neither the presence/absence of an attendant nor rest time significantly impacted AOBP measurement. A single set of AOBP measurements may be insufficient for making a new diagnosis of hypertension.