Elevated Blood Pressure in the Emergency Department: A Risk Factor for Incident Cardiovascular Disease

Abstract

In the emergency department (ED), high blood pressure (BP) is commonly observed but mostly used to evaluate patients' health in the short term. We aimed to study whether ED-measured BP is associated with incident atherosclerotic cardiovascular disease (ASCVD), myocardial infarction, or stroke in long term, and to estimate the number needed to screen to prevent ASCVD. In this cohort study, participants were selected from a university hospital between 2010 and 2016, with an obtained BP in the ED. The outcome information was acquired through the Swedish National Patient Register for all participants. The association was estimated with Cox-regression. Among the included 300 193 subjects, 8999 incident ASCVD events occurred during a median follow-up for 3.5 years. Both DBP and systolic blood pressure were associated with incident ASCVD, myocardial infarction, and stroke with a progressively increased risk for systolic blood pressure within hypertension grade 1 (HR, 1.15 [95% CI, 1.06-1.24]), 2 (HR, 1.35 [95% CI, 1.25-1.47]), and 3 (HR, 1.63 [95% CI, 1.49-1.77]). The 6-year cumulative incidence of ASCVD was 12% for systolic blood pressure ≥180 mm Hg compared with 2% for normal levels. To prevent one ASCVD event during the median follow-up, the number needed to screen was estimated to 151, whereas the number needed to treat to 71. ED-recorded BP is associated with incident ASCVD, myocardial infarction, and stroke. High-BP recordings in EDs should not be disregarded but an opportunity to detect and improve the treatment of hypertension. ED-measured BP provides an important and underused tool with great potential to reduce morbidity and mortality associated with hypertension. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT03954119.

Keywords: blood pressure; hypertension; incidence; myocardial infarction; stroke.