Systemic inflammation status at admission affects the outcome of intracerebral hemorrhage by increasing perihematomal edema but not the hematoma growth

Abstract

Acute stress and inflammation responses are associated with worse outcomes in intracerebral hemorrhage (ICH) but the precise mechanisms involved are unclear. We evaluated the effect of neutrophil-to-lymphocyte ratio (NLR) in ICH outcome, with focus on hematoma expansion and early cerebral edema. In a retrospective study, we included all patients with primary ICH admitted to our center within 24-h from symptom onset from January 2014 to February 2015. We retrieved demographic and medical history data, Glasgow Coma Scale scores, blood cell counts, glucose, and C-reactive protein, and calculated NLR. We obtained hematoma volumes by computerized planimetry. Outcomes included independence at 90days (modified Rankin scale 0-2), mortality at 30days, significant hematoma expansion (> 33% or > 6mL) and early cerebral edema causing significant midline shift (> 2.5mm) at 24h. We included 135 patients. NLR independently associated with independence at 90days (adjusted odds ratio (aOR) 0.79, 95% CI 0.67-0.93, p = 0.006) significant cerebral edema (aOR 1.08, 95%CI 1.01-1.15, p = 0.016) but not hematoma expansion (aOR 0.99, 95%CI 0.94-1.04, p = 0.736). The severity of midline shift was positively correlated with NLR (adjusted beta = 0.08, 95% CI 0.05-0.11, p < 0.001). In ICH, an immediate and intense systemic inflammatory response reduces the likelihood of a better functional outcome at 90days, which is more likely to be explained by perihematomal edema growth than due to a significant hematoma expansion. These findings could have implications in new treatment strategies and trial designs, which endpoints tend to target exclusively hematoma enlargement.