The Magnitude of Blood Pressure Reduction Predicts Poor In-Hospital Outcome in Acute Intracerebral Hemorrhage

Abstract

Early systolic blood pressure (SBP) reduction is believed to improve outcome after spontaneous intracerebral hemorrhage (ICH), but there has been a limited assessment of SBP trajectories in individual patients. We aimed to determine the prognostic significance of SBP trajectories in ICH. We collected routine data on spontaneous ICH patients from two healthcaresystems over 10years. Unsupervised functional principal components analysis (FPCA) was used to characterize SBP trajectories over first 24h and their relationship to the primary outcome of unfavorable shift on modified Rankin scale (mRS) at hospital discharge, categorized as an ordinal trichotomous variable (mRS 0-2, 3-4, and 5-6 defined as good, poor, and severe, respectively). Ordinal logistic regression models adjusted for baseline SBP and ICH volume were used to determine the prognostic significance of SBP trajectories. The 757 patients included in the study were 65 ± 23years old, 56% were men, with a median (IQR) Glasgow come scale of 14 (8). FPCA revealed that mean SBP over 24h and SBP reduction within the first 6h accounted for 76.8% of the variation in SBP trajectories. An increase in SBP reduction (per 10mmHg) was significantly associated with unfavorable outcomes defined as mRS > 2 (adjusted-OR = 1.134; 95% CI 1.044-1.233, P = 0.003). Compared with SBP reduction < 20mmHg, worse outcomes were observed for SBP reduction = 40-60mmHg (adjusted-OR = 1.940, 95% CI 1.129-3.353, P = 0.017) and > 60mmHg, (adjusted-OR = 1.965, 95% CI 1.011, 3.846, P = 0.047). Furthermore, the association of SBP reduction and outcome varied according to initial hematoma volume. Smaller SBP reduction was associated with good outcome (mRS 0-2) in small (< 7.42mL) and medium-size (≥ 7.42 and < 30.47mL) hematomas. Furthermore, while the likelihood of good outcome was low in those with large hematomas (≥ 30.47mL), smaller SBP reduction was associated with decreasing probability of severe outcome (mRS 5-6). Our analyses suggest that in the first 6h SBP reduction is significantly associated with the in-hospital outcome that varies with initial hematoma volume, and early SBP reduction > 40mmHg may be harmful in ICH patients. For early SBP reduction to have an effective therapeutic effect, both target levels and optimum SBP reduction goals vis-à-vis hematoma volume should be considered.