Clinical and radiologic differences between primary intracerebral hemorrhage with and without microbleeds on gradient-echo magnetic resonance images

Background: Microbleeds on gradient-echo magnetic resonance (MR) imaging reflect bleeding-prone microangiopathy. The microbleeds are frequently detected in patients with primary intracerebral hemorrhage (PICH). However, some patients do not have microbleeds. Objective: To clarify the risk factors associated with microbleeds in PICH, thus providing insight into the pathogenesis of PICH. Design: Prospective study. Setting: Neurology department of a tertiary referral center. Patients: A consecutive series of 107 patients with PICH. Interventions: Gradient-echo MR imaging to deter mine distribution patterns and numbers of micro bleeds. Main Outcome Measures: Clinical variables and the associated MR imaging abnormalities in patients with PICH with and without microbleeds. Results: Patients with PICH who had microbleeds were significantly older (65.9 +/- 10.9 years) than those without microbleeds (53.9 +/- 13.0 years; P<.001), and previous stroke, medication with antithrombotics or anticoagulants, lacunes, and leukoaraiosis were more common in patients with microbleeds. However, potential triggering events tending to raise the blood pressure were more common in cases of PICH without microbleeds (18 [56.3%] vs 10 [15.4%]). In logistic regression analysis, age (odds ratio and 95% confidence interval: 1.07, 1.01-1.14), advanced leukoaraiosis (7.79, 1.05-57.74), number of lacunes (1.66, 1.21-2.28), and potential triggering events (0.18, 0.04-0.90) were independent risk factors associated with the presence of microbleeds in patients with PICH. Conclusions: Primary intracerebral hemorrhage without microbleeds was more common in younger patients with precipitating events, whereas PICH with microbleeds was more common in elderly patients with prominent ischemic change and frequent use of antithrombotics or anticoagulants. Our findings might help to determine the pathogenetic type for secondary prevention.