Risk of intracranial haemorrhage and ischaemic stroke after convexity subarachnoid haemorrhage in cerebral amyloid angiopathy: international individual patient data pooled analysis
Isabel C. Hostettler, Duncan Wilson, Catherine Arnold Fiebelkorn, Diane J. Aum, Sebastián F. Ameriso, Federico Eberbach, Markus Beitzke, Timothy Kleinig, Thanh G. Phan, Sarah Marchina, Romain Schneckenburger, María Carmona‐Iragui, Andreas Charidimou, Isabelle Mourand, Sara Parreira, Gareth Ambler, Hans Rolf Jäger, Shaloo Singhal, John Ly, Henry Ma, Emmanuel Touzé, Ruth Geraldes, Ana Catarina Fonseca, Teresa Pinho e Melo, Pierre Labauge, Pierre-Henri Lefèvre, Anand Viswanathan, Steven M. Greenberg, Juan Fortea, Marion Apoil, Marion Boulanger, Fausto Viader, Sandeep Kumar, Velandai Srikanth, Ashan Khurram, Franz Fazekas, Verónica Bruno, Gregory J. Zipfel, Daniel Refai, Alejandro A. Rabinstein, Jonathan Graff-Radford, David J. Werring
Abstract
OBJECTIVE: To investigate the frequency, time-course and predictors of intracerebral haemorrhage (ICH), recurrent convexity subarachnoid haemorrhage (cSAH), and ischemic stroke after cSAH associated with cerebral amyloid angiopathy (CAA). METHODS: We performed a systematic review and international individual patient-data pooled analysis in patients with cSAH associated with probable or possible CAA diagnosed on baseline MRI using the modified Boston criteria. We used Cox proportional hazards models with a frailty term to account for between-cohort differences. RESULTS: We included 190 patients (mean age 74.5 years; 45.3% female) from 13 centers with 385 patient-years of follow-up (median 1.4 years). The risks of each outcome (per patient-year) were: ICH 13.2% (95% CI 9.9-17.4); recurrent cSAH 11.1% (95% CI 7.9-15.2); combined ICH, cSAH, or both 21.4% (95% CI 16.7-26.9), ischemic stroke 5.1% (95% CI 3.1-8) and death 8.3% (95% CI 5.6-11.8). In multivariable models, there is evidence that patients with probable CAA (compared to possible CAA) had a higher risk of ICH (HR 8.45, 95% CI 1.13-75.5, p = 0.02) and cSAH (HR 3.66, 95% CI 0.84-15.9, p = 0.08) but not ischemic stroke (HR 0.56, 95% CI 0.17-1.82, p = 0.33) or mortality (HR 0.54, 95% CI 0.16-1.78, p = 0.31). CONCLUSIONS: Patients with cSAH associated with probable or possible CAA have high risk of future ICH and recurrent cSAH. Convexity SAH associated with probable (vs possible) CAA is associated with increased risk of ICH, and cSAH but not ischemic stroke. Our data provide precise risk estimates for key vascular events after cSAH associated with CAA which can inform management decisions.