Body Position and Orthostatic Hypotension in Hypertensive Adults: Results from the Syst-Eur Trial

Abstract

Background: We recently demonstrated that more intensive blood pressure (BP) treatment lowered risk of orthostatic hypotension (OH) measured with a seated-to-standing protocol. However, seated-to-standing OH assessments are less sensitive than supine-to-standing and could miss clinically relevant OH. Objectives: Using data from the Syst-Eur trial (Systolic Hypertension in Europe), we examined the effect of hypertension treatment on incidence of OH based on the difference in BP from 3 body positions. Methods: Syst-Eur was a multi-center, randomized trial that enrolled adults with isolated systolic hypertension to investigate whether active hypertension treatment could reduce cardiovascular events. Participants underwent BP measurement in supine, seated, and standing positions. Using differences in BP between the 3 body positions (seated minus supine, standing minus seated, and standing minus supine), we defined OH as a drop in systolic BP ≥20 mm Hg or diastolic BP ≥10 mm Hg. We included measurements from baseline and follow-up visits. Results: Among 4695 participants (mean age, 70.2±6.7 years; 66.9% female) with 42 636 BP measurements, OH was present in 4.9% of measures with supine-to-seated, 7.9% with seated-to-standing, and 11.4% with supine-to-standing protocols, respectively. Compared with placebo, BP treatment did not increase OH with any set of maneuvers, OR, 0.79 (95% CI, 0.65–0.95) with seated-to standing, 1.03 (95% CI, 0.86–1.24) with supine-to-seated, and 0.99 (95% CI, 0.86–1.15) with supine-to-standing. Conclusions: Regardless of protocol, active hypertension treatment did not increase the risk of OH, reinforcing evidence that OH should not be viewed as a complication of hypertension treatment. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02088450.