Lodhi HA, et al. - Given that increased variability in blood pressure (BPV) and nondipping status observed on 24-hour ambulatory BP monitoring (ABPM) are frequently observed in autonomic failure (ATF), researchers determined the usefulness of BPV indices derived from ABPM—including SD, coefficient of variation, average real variability, variation independent of mean, and residual standard deviation—in detecting ATF. They evaluated BPV and nocturnal BP dipping in 273 patients undergoing ABPM at Southwestern Medical Center between 2010 and 2017. Patients have been divided into a discovery cohort (n=201) and a validation cohort (n=72). According to findings, increased variability of daytime BP, but not nocturnal BP, was related to autonomic dysfunction in the patients referred for 24-hour ABPM. In detecting autonomic dysfunction, daytime SD of systolic BP is a better screening tool than nondipping status.