Background and purpose: Small asymptomatic cerebral hemorrhages detectable by gradient-echo MRI are common in patients with intracerebral hemorrhage (ICH), particularly lobar ICH related to cerebral amyloid angiopathy (CAA). We sought to determine whether hemorrhages detected at the time of lobar ICH predict the major clinical complications of CAA: recurrent ICH or decline in cognition and function.
Methods: Ninety-four consecutive survivors of primary lobar ICH (age > or =55) with gradient-echo MRI at presentation were followed in a prospective cohort study for 32.9+/-24.0 months. A subset of 34 subjects underwent a second MRI after a stroke-free interval of 15.8+/-6.5 months. Study endpoints were recurrent symptomatic ICH or clinical decline, defined as onset of cognitive impairment, loss of independent functioning, or death.
Results: The total number of hemorrhages at baseline predicted risk of future symptomatic ICH (3-year cumulative risks 14%, 17%, 38%, and 51% for subjects with 1, 2, 3 to 5, or > or =6 baseline hemorrhages, P=0.003). Higher numbers of hemorrhages at baseline also predicted increased risk for subsequent cognitive impairment, loss of independence, or death (P=0.002) among subjects not previously demented or dependent. For subjects followed after a second MRI, new microhemorrhages appeared in 17 of 34 and predicted increased risk of subsequent symptomatic ICH (3-year cumulative risks 19%, 42%, and 67% for subjects with 0, 1 to 3, or > or =4 new microhemorrhages, P=0.02), but not subsequent clinical decline.
Conclusions: Hemorrhages identified by MRI predict clinically important events in survivors of lobar ICH. Detection of microhemorrhages may be useful for assessing risk in ICH patients and as a surrogate marker for clinical studies.