Contribution of Deep Microbleeds to Stroke Recurrence: Differences between Patients with Past Deep Intracerebral Hemorrhages and Lacunar Infarctions.

Background: This study investigated the contribution of deep cerebral microbleeds (MBs) to stroke recurrences in patients with histories of deep intracerebral hemorrhages (ICHs) or lacunar infarctions (LIs).

Methods: We prospectively analyzed stroke recurrences in patients admitted to our hospital who were treated for deep ICHs or LIs between April 2004 and December 2011. The number of deep MBs was counted on admission. Stroke recurrence-free rate curves were generated with the Kaplan-Meier method using the log-rank test. The odds ratios (ORs) for recurrent strokes were derived using multivariate logistic regression models, based on deep MBs and risk factors.

Results: We evaluated magnetic resonance images or the recurrences of 231 deep-ICH patients (92 women, 68.0 ± 12.0 years old) and 309 LI patients (140 women, 70.7 ± 11.7 years old). The incidences of deep ICHs (1.5%/year) and LIs (2.1%/year) presenting as stroke recurrences were significantly larger in LI patients with deep MBs than in those without (.01 [P = .0001] and .08%/year [P = .005], respectively). However, there was no significant difference between deep-ICH patients with and without MBs in terms of incidence of recurrences. Multivariate analyses revealed that deep MBs independently and significantly elevated the rate of deep ICHs (OR, 19.0; P = .007) or LIs (OR, 3.62; P = .008) presenting as recurrences in LI patients, but not in deep-ICH patients, when adjusted for stroke risk factors.

Conclusions: There may be differences between patients with deep ICHs and those with LIs in terms of the contribution of deep MBs to stroke recurrence.