Abstract 213: Cerebral Microbleeds in 1278 Lacunar Stroke Patients: The Secondary Prevention of Small Subcortical Strokes (SPS3) Trial
Background: Cerebral microbleeds (CMBs) are radiographic markers of cerebral small vessel disease (CSVD) reported to independently predict recurrent stroke and mortality. However, characterization of CMBs in a large population of pure CSVD is lacking. We aimed to characterize CMBs in a well-defined population of lacunar stroke patients, and assess the relationship between CMBs and recurrent stroke and death. Methods: SPS3 was a randomized trial investigating optimal blood pressure target and antiplatelet regimen in 3020 patients with recent, symptomatic, MRI-confirmed lacunar stroke. CMBs were rated as per the Brain Observer MicroBleed Scale in all participants who had an interpretable axial T2*- GRE sequence available as part of their baseline MRI (n=1278, intra-rater reliability for + CMB 91% agreement, Kappa = 0.82). Results: CMBs were present in 30% of 1278 patients (mean age 63 y, 65% male, 75% history of hypertension). CMBs were lobar in 21%, deep in 44%, and mixed in 35% of cases. Of patients with CMBs, most (57%) had 1-2 CMBs, 31% had 3-10, and 12% >10. Male gender (OR 1.7, 95% CI 1.3-2.3), history of hypertension (1.6, 1.2-2.3), increased systolic blood pressure (1.2 per 20 mmHg, 1.1-1.4), non-diabetic (1.4, 1.1-1.9), multiple lacunar infarcts (1.9, 1.5-2.5) and moderate (1.7, 1.2-2.3) or severe (4.2, 3.0-5.9) white matter hyperintensities on MRI were independently associated with the odds of having CMBs in multivariable logistic regression. During a mean follow-up of 3.3 y, overall stroke recurrence was 2.5% per patient-y. In comparison to patients without CMBs, those with CMBs had a two-fold increased risk of stroke (HR 2.1, 1.4-3.1), after adjusting for assigned treatments and risk factors, whereas those with >10 CMBs had a four-fold increased risk (HR 4.0, 1.8-8.7). CMBs were not a risk factor for death (HR 1.2, 0.8-2.0). There were no interactions between CMBs and treatment assignments. Conclusions: In this largest reported cohort of lacunar stroke investigating CMBs, CMBs were highly prevalent and an independent predictor of stroke recurrence. Accordingly, patients with lacunar stroke and CMBs likely represent a more aggressive form of CSVD in need of efficacious therapeutic strategies. Further research is warranted in this field.