Abstract P208: Utility Of Standing Office Blood Pressure In Assessing Blood Pressure Control In Patients With Autonomic Failure

Current guidelines recommend blood pressure (BP) target based on office BP taken in a seated position for hypertensive patients. However, the accuracy of standing BP measurements for determining blood pressure control in patients with autonomic (ATF) is unknown.We measured BP in seated and standing positions in 47 hypertensive and normotensive adults with ATF. Office BP was measured in the seated position 3 times and after standing for 3 minutes. Adequate BP control 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 assessing BP control. 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 determining blood pressure control was derived using cut-off points derived from Youden’s Index.Prevalence of HTN was 72% (34/47) and the mean age was 71 ± 11 years. Sensitivity and specificity of seated SBP was 65% and 73%, respectively. Optimal cutoffs selected by Youden’s index for standing SBP/DBP was 104/83 mmHg. Sensitivity and specificity of standing SBP was 96% and 64%, respectively. The AUROC of standing SBP was significantly higher when compared to seated SBP alone, when controlled SBP was defined as 24-Hr SBP < 125 mmHg (BF > 3). Similarly, when controlled SBP was defined as daytime SBP < 130 mmHg, the AUROC of 3 rd standing was significantly higher when compared to seated SBP alone or in combination (BF > 3).In conclusion, standing SBP is more useful than seated SBP in assessing BP control in patients with ATF.