Cortical superficial siderosis: A prospective observational cohort study.

OBJECTIVE: To determine the prevalence of cortical superficial siderosis (cSS), its clinical and neuroimaging associated markers, and its influence on the risk of recurrent intracerebral hemorrhage (ICH) in a prospective observational ICH cohort.

METHODS: We investigated clinical and radiologic markers associated with cSS using multivariable analysis. In survival analyses, we used Cox models to identify predictors of recurrent ICH after adjusting for potential confounders.

RESULTS: Of the 258 patients included in the study, 49 (19%; 95% confidence interval [CI] 14%-24%) had cSS at baseline. Clinical factors independently associated with the presence of cSS were increasing age (odds ratio [OR] 1.03 per 1-year increase, 95% CI 1.001-1.06, p = 0.044), preexisting dementia (OR 2.62, 95% CI 1.05-6.51, p = 0.039), and history of ICH (OR 4.02, 95% CI 1.24-12.95, p = 0.02). Among radiologic biomarkers, factors independently associated with the presence of cSS were ICH lobar location (OR 24.841, 95% CI 3.2-14.47, p < 0.001), severe white matter hyperintensities score (OR 5.51, 95% CI 1.17-5.78, p = 0.019), and absence of lacune (OR 4.46, 95% CI 1.06-5.22, p = 0.035). During a median follow-up of 6.4 (interquartile range 2.9-8.4) years, recurrent ICH occurred in 19 patients. Only disseminated cSS (hazard ratio 4.69, 95% CI 1.49-14.71, p = 0.008), not the presence or absence of cSS or focal cSS on baseline MRI, was associated with recurrent symptomatic ICH.

CONCLUSION: In a prospective observational cohort of spontaneous ICH, clinical and radiologic markers associated with cSS suggest the implication of underlying cerebral amyloid angiopathy. Disseminated cSS may become a key prognostic neuroimaging marker of recurrent ICH that could be monitored in future clinical trials dedicated to patients with ICH.