Elevated blood pressure in the emergency department - a risk factor for incident cardiovascular disease: An EHR-based cohort study
Objectives: 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 (MI), or stroke in long-term, and to estimate the number needed to screen (NNS) to prevent ASCVD. Design: Electronic Health Records (EHR) and national register-based cohort study. The association between
... ssociation between BP and incident ASCVD was studied with Cox-regression. Setting: Two university hospital emergency departments in Sweden. Data sources: BP data were obtained from EDs EHR, and outcome information was acquired through the Swedish National Patient Register for all participants. Participants: All patients ≥18 years old who visited the EDs between 2010 to 2016, with an obtained BP (n=300,193). Main outcome measures: Incident ASCVD, MI, and stroke during follow-up. Results: The subjects were followed for a median of 42 months. 8,999 incident ASCVD events occurred (MI: 4,847, stroke: 6,661). Both diastolic and systolic BP (SBP) was associated with incident ASCVD, MI, and stroke with a progressively increased risk for SBP within hypertension grade 1 (HR 1.15, 95% CI 1.06 to 1.24), 2 (HR 1.35, 95% CI 1.25 to 1.47), and 3 (HR 1.63, 95% CI 1.49 to 1.77). The six-year cumulative incidence of ASCVD was 12% for patients with SBP ≥180 mmHg compared to 2% for normal levels. To prevent one ASCVD event during the median follow-up, NNS was estimated to 151, whereas NNT to 71. Conclusions: BP in the ED is associated with incident ASCVD, MI, and stroke. High BP recordings in EDs should not be disregarded as isolated events, but an opportunity to detect and improve treatment of hypertension. ED-measured BP provides an important and under-used tool with great potential to reduce morbidity and mortality associated with hypertension.