Cumulative Dose of Hypertension Predicts Outcome in Intracranial Hemorrhage Better Than American Heart Association Guidelines

Abstract

Background: Hypertension is common after intracranial hemorrhage (ICH) and may be associated with higher mortality and adverse neurologic outcome. The American Heart Association recommends that blood pressure be maintained at a mean arterial pressure (MAP) less than 130 mm Hg to prevent secondary brain injury. Objectives: To prospectively evaluate whether a new method of assessing hypertension in ICH more accurately identifies patients at risk for adverse outcomes. Methods: The authors prospectively studied all patients presenting to two University of California, San Francisco hospitals with acute ICH from June 1, 2001, to May 31, 2004. Factors related to acute hospitalization were recorded in a database, including all charted vital signs for the first 15 days. Patients were followed up for one year, with their modified Rankin Scale (mRS) score at 12 months as primary outcome. Hypertension dose was determined as the area under the curve between patient MAP and a cut point of 110 mm Hg while in the emergency department (ED). The dose was adjusted for time spent in the ED (dose/timeed [d/ted]). Hypertension dose was divided into four categories (none, and progressive tertiles). Multivariate logistic regression was used to calculate the odds ratio for adverse mRS by tertiles of d/ted. Results: A total of 237 subjects with an ED average (±SD) length of stay of 3.42 (±3.7) hours were enrolled. In a multivariate logistic regression model controlling for the effects of age, volume of hemorrhage, presence of intraventricular hemorrhage, race, and preexisting hypertension, there was a 4.7- and 6.1-fold greater likelihood of an adverse neurologic outcome (by mRS) at one and 12 months, respectively, in the highest d/ted tertile relative to the referent group without hypertension. Conclusions: Hypertension after acute ICH is associated with adverse neurologic outcome. The dose of hypertension may more accurately identify patients at risk for adverse outcomes than the American Heart Association guidelines and may lead to better outcomes if treated when identified in this manner. © 2007 Society for Academic Emergency Medicine.