Outcome after spontaneous and arteriovenous malformation-related intracerebral haemorrhage: population-based studies

Spontaneous (non-traumatic) intracerebral haemorrhage (ICH) has a high case-fatality and leaves many survivors disabled. Clinical characteristics and outcome seem to vary according to the cause of ICH, but population-based comparisons are scarce. We studied two prospective, population-based cohorts to determine differences in outcome [case-fatality and modified Rankin Scale (mRS)] after incident ICH due to brain arteriovenous malformations (AVM) [Scottish Intracranial Vascular Malformation Study (SIVMS), n = 90] and spontaneous ICH [Oxford Vascular Study (OXVASC), n = 60]. Patients with AVM-ICH were younger, had lower pre-stroke and admission blood pressure (BP), higher admission Glasgow Coma Scale (GCS) and were more likely to have an ICH in a lobar location than patients with spontaneous ICH (sICH). Case fatality throughout 2-year follow-up was greater following sICH than AVM-ICH [34/56 (61%) versus 11/90 (12%) at 1 year, odds ratio (OR) 11 (95% Confidence Interval (CI) 5-25)], as was death or dependence (mRS >or= 3) [40/48 (83%) versus 26/65 (40%) at 1 year, OR 8 (3-19)]. Differences in outcome persisted following stratification by age and sensitivity analyses. In multivariable analyses of 1 year outcome, independent predictors of death were sICH (OR 21, 4-104) and increasing ICH volume (OR 1.03, 1.01-1.05), and independent predictors of death or dependence were sICH (OR 11, 2-62) and GCS on admission (OR 0.79, 0.67-0.93). Outcome after AVM-ICH is better than after sICH, independent of patient age and other known predictors of ICH outcome.