Matrix metalloproteinase-9 concentration after spontaneous intracerebral hemorrhage

Object. Matrix metalloproteinases (MMPs) are overexpressed in the presence of some neurological diseases in which blood-brain barrier disruption exists. The authors investigated the MMP-9 concentration in patients after acute intracerebral hemorrhage (ICH) and its relation to perihematomal edema (PHE). Methods. Concentrations of MMP-9 and related proteins were determined in plasma by performing an enzyme-linked immunosorbent assay of samples drawn after hospital admission (< 24 hours after stroke) from 57 patients with ICH. The diagnosis of ICH was made on the basis of findings on computerized tomography (CT) scans. The volumes of ICH and PHE were measured on baseline and follow-up CT scans at the same time that the patient's neurological status was assessed using the Canadian Stroke Scale and the Glasgow Coma Scale. Increased expression of MMP-9 was found among patients with ICH. In cases of deep ICH, MMP-9 was significantly associated with PHE volume (r = 0.53; p = 0.01) and neurological worsening (237.4 compared with 111.3 ng/ml MMP-9; p = 0.04). A logistic regression model focusing on the study of absolute PHE volume showed ICH volume as an independent predictor (odds ratio [OR] 3.37; 95% confidence interval [CI] 1.1-10.3; p = 0.03). A second analysis of relative PHE volume (absolute PHE volume/ICH volume) in patients with deep ICH demonstrated that the only factor related to it was MMP-9 concentration (OR 11.6; 95% CI 1.5-89.1; p = 0.018). Conclusions. Expression of MMP-9 is raised after acute spontaneous ICH. Among patients with deep ICH this increase is associated with PHE and the development of neurological worsening within the acute stage.