Abstract P125: Performance of Ambulatory Blood Pressure Monitoring in Predicting Autonomic Dysfunction

Abstract

Background: We investigated the predictive performance of orthostatic hypotension (OH) and ambulatory blood pressure monitoring (ABP) to predict autonomic dysfunction. Methods: In this retrospective analysis, statistical associations among the candidate variables were investigated and comparisons of predictive performances were performed using Receiver Operating Characteristics (ROC) curves. Results: Ninety-four patients were included for analysis. No significant correlations could be demonstrated between OH and components of ABP (reversal of circadian pattern, postprandial hypotension and heart rate variability), nor between OH and autonomic reflex screen. Reversal of circadian pattern did not demonstrate significant correlation (r= 0.12, p=0.237) with autonomic reflex screen, but postprandial hypotension (r=0.39, p=0.003) and heart rate variability (r=0.27, p=0.009) demonstrated significant correlations. Postprandial hypotension was associated with a five-fold (OR 4.83, CI95% 1.6 - 14.4, p=0.005) increased risk and heart rate variability with a four-fold (OR 3.75, CI95% 1.3-10.6, p=0.013) increased risk for autonomic dysfunction. Per ROC curves, heart rate variability (0.671, CI 95% 0.53-0.81, p=0.025) and postprandial hypotension (0.668, CI 95% 0.52-0.72, p=0.027) were among the best predictors of autonomic dysfunction in routine clinical practice. Conclusions: Postprandial hypotension and heart rate variability on ambulatory blood pressure monitoring are strong predictors of autonomic dysfunction in routine clinical practice.