Association Between Hyperacute Blood Pressure Variability and Hematoma Expansion After Intracerebral Hemorrhage: Secondary Analysis of the FAST-MAG Database.

Abstract

Blood pressure variability (BPV) has emerged as a significant factor associated with clinical outcomes after intracerebral hemorrhage (ICH). Although hematoma expansion (HE) is associated with clinical outcomes, the relationship between BPVthat encompassesprehospital data and HE is unknown. We hypothesized that BPV was positively associated with HE. We analyzed 268 patients with primary ICH enrolled in the National Institutes of Health-funded Field Administration of Stroke Therapy-Magnesium (FAST-MAG) study who received head computed tomography or magnetic resonance imaging on arrival to the emergency department (ED) and repeat imaging within 6-48h. BPV was calculated by standard deviation (SD) and coefficient of variation (CV) from prehospital data as well as systolic blood pressure (SBP) measurements taken on ED arrival, 15min post antihypertensive infusion start, 1h post maintenance infusion start, and 4h after ED arrival. HE was defined by hematoma volume expansion increase > 6mL or by 33%. Univariate logistic regression was used for presence of HE in quintiles of SD and CV of SBP for demographics and clinical characteristics. Of the 268 patients analyzed from the FAST-MAG study, 116 (43%) had HE. Proportions of patients with HE were not statistically significant in the higher quintiles of the SD and CV of SBP for either the hyperacute or the acute period. Presence of HE was significantly more common in patients on anticoagulation. Higher BPV was not found to be associated with occurrence of HE in the hyperacute or the acute period of spontaneous ICH. Further study is needed to determine the relationship.