Predictors of localization, outcome, and etiology of spontaneous intracerebral hemorrhages: focus on cerebral amyloid angiopathy

Abstract

Despite its clinical relevance, cerebral amyloid angiopathy (CAA) is underdiagnosed worldwide. This retrospective study aimed to assess the incidence, etiology, predictors, and outcome of intracerebral hemorrhages (ICHs) in this region, with special focus on possible underlying CAA. Database screening of acute cares with intracranial hemorrhage diagnosis within 01/07/2014-01/07/2018 were conducted analyzing medical records and imaging. Spontaneous ICHs were classified as deep (basal ganglionic/thalamic/brainstem) and lobar/cerebellar (i.e., CAA-compatible) ICHs. Probable/definite CAA was established using the modified Boston criteria in a subgroup with 'complete' radiological/neuropathological work-up. The ability of several factors to discriminate between deep and lobar/cerebellar ICHs, between probable/definite CAA and non-probable CAA cases, and to predict 1-month case fatality was assessed. Of the 213 ICHs identified, 121 were in deep and 92 in lobar/cerebellar localization. Sub-analysis of 47 lobar/cerebellar ICHs with 'complete' work-up identified 16 probable/definite CAA patients, yielding an estimated 14.7% prevalence of CAA-related ICHs. Chronic hypertension was the most prevalent risk factor for all types of ICHs (including CAA-related), with hypertensive excess and younger age being independent predictors of deep whereas antiplatelet use of lobar/cerebellar localization. The 1-month case fatality was 33.8%, driven predominantly by age and INR > 1.4. Probable/definite CAA diagnosis was independently predicted by age, prior intracranial hemorrhage, and antiplatelet use. First in this region and among the few in the literature, this study reports a remarkable prevalence of CAA-related ICHs, emphasizing the need for an increased awareness of CAA and its therapeutic implications, especially regarding antiplatelets among the elderly.

Keywords: Cerebral amyloid angiopathy; Epidemiology; Intracerebral hemorrhage; Lobar; Predictor.

Fig. 1

Flow diagram of the process of identifying spontaneous intracerebral hemorrhages (ICHs)

Fig. 2

a Localization of spontaneous intracerebral hemorrhages (ICHs). b The distribution of underlying etiologies within lobar/cerebellar ICHs

Fig. 3

Representative axial MRI-SWI images of probable CAA patients at different parts of the spectrum. a Diffuse CSS with multiple lobar CMBs and ICHs of different ages. b Diffuse (but less extensive) CSS with a recurrent lobar ICH and a single CMB. c No CSS but multiple lobar CMBs accompanying a recent lobar ICH. The deep structures (i.e., basal ganglia, thalamus, and brainstem) are consistently devoid of hemorrhagic pathology. CAA cerebral amyloid angiopathy, CMB cerebral microbleed, CSS cortical superficial siderosis, ICH intracerebral hemorrhage, MRI magnetic resonance imaging, SWI susceptibility-weighted imaging