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 ≥ 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.