Aspirin Treatment Increases the Risk of Cerebral Microbleeds

Background: The objective of the study was to determine the frequency of cerebral microbleeds (CMBs) by using phase-sensitive imaging in patients with previous transient ischemic attack (TIA) or stroke who were receiving aspirin treatment. Methods: We retrospectively analyzed 300 outpatients with ischemic cerebrovascular disease: 150 had been receiving aspirin treatment for >1 year (patients), and 150 controls had not previously received aspirin. Cerebral microbleeds were defined by a trained observer (blinded to clinical details) according to results of T2-weighted, T1-weighted, diffusion-weighted, and phase-sensitive magnetic resonance imaging (MRI). Numerous vascular risk factors including white matter hyperintensity (WMH), duration of aspirin treatment, age, hypertension or diabetes mellitus were investigated for a possible association with the presence of CMBs in the two groups. Results: The frequency of CMBs (60/150 (40%) vs 18/150 (12%); odds ratio 4.899, p <0.0001) and intracerebral hemorrhage (ICH)(42/150 (28%) vs 2/150 (1%); odds ratio 28.778, p <0.0001) were significantly higher in the patients than in the controls. Among patients, those using aspirin for >5 years(42/68 (62%) showed a higher frequency of CMBs than those receiving aspirin for 5 years(18/82 (22%); odds ratio 5.744, p<0.0001). WMH (p=0.020/0.030, 0.007/0.000) age (p=0.007/0.000) and hypertension (p=0.000/0.033), in patients and controls respectively, were each associated with CMBs. Conclusions: There was a clear impact of aspirin treatment on CMBs associated with intracerebral hemorrhage in Chinese patients. The frequency of CMBs and hemorrhagic complications was higher in patients treated with long-term aspirin.