Convexity subarachnoid hemorrhage in lobar intracerebral hemorrhage: A prognostic marker

Abstract

Objective: To investigate whether acute convexity subarachnoid hemorrhage (cSAH) associated with acute lobar intracerebral hemorrhage (ICH) increases the risk of ICH recurrence in patients with cerebral amyloid angiopathy (CAA).

Methods: We analyzed data from a prospective cohort of consecutive survivors of acute spontaneous lobar ICH fulfilling the Boston criteria for possible or probable CAA (CAA-ICH). We analyzed baseline clinical and MRI data, including cSAH (categorized as adjacent or remote from ICH on a standardized scale), cortical superficial siderosis (cSS), and other CAA MRI markers. Multivariable Cox regression models were used to assess the association between cSAH and recurrent symptomatic ICH during follow-up.

Results: We included 261 CAA-ICH survivors (mean age 76.2 ± 8.7 years). Of them, 166 (63.6%, 95% confidence interval [CI] 57.7%-69.5%) had cSAH on baseline MRI. During a median follow-up of 28.3 (interquartile range 7.2-57.0) months, 54 (20.7%) patients experienced a recurrent lobar ICH. In Cox regression, any cSAH, adjacent cSAH, and remote cSAH were independent predictors of recurrent ICH after adjustment for other confounders, including cSS. Incidence rate of recurrent ICH in patients with cSAH was 9.9 per 100 person-years (95% CI 7.3-13.0) compared with 1.2 per 100 person-years (95% CI 0.3-3.2) in those without cSAH (adjusted hazard ratio 7.5, 95% CI 2.6-21.1).

Conclusion: In patients with CAA-related acute ICH, cSAH (adjacent or remote from lobar ICH) is commonly observed and heralds an increased risk of recurrent ICH. cSAH may help stratify bleeding risk and should be assessed along with cSS for prognosis and clinical management.

Figure 1. Representative examples of cSAH associated with lobar ICH

(A–C) Axial fluid-attenuated inversion recovery and (D–F) T2*-gradient recalled echo of 3 cases of cerebral amyloid angiopathy–related acute intracerebral hemorrhage (ICH). (A and D) Patient without convexity subarachnoid hemorrhages (cSAH): acute right frontal ICH without evidence of cSAH. (B and E) Patient with adjacent cSAH: cSAH (white arrow) was observed in 3 sulci adjacent to the acute left frontal ICH. (C and F) Patient with remote cSAH: cSAH (white arrowhead) was detected in the left frontal lobe, remote from the acute right frontal ICH.

Figure 2. Flow diagram

CAA = cerebral amyloid angiopathy; ICH = intracerebral hemorrhage.

Figure 3. Probability of recurrent symptomatic ICH according to the presence and extent of cSAH at baseline

Kaplan-Meier analyses showing time to recurrent symptomatic intracerebral hemorrhage (ICH) according to the (A) presence and (B) extent of convexity subarachnoid hemorrhage (cSAH) on baseline MRI in patients with cerebral amyloid angiopathy–related ICH. Testing of significance by the log-rank test.