Cerebral amyloid angiopathy linked to higher risk for subdural hemorrhage

Cerebral amyloid angiopathy was associated with a higher risk for isolated nontraumatic subdural hemorrhage in two large, independent cohorts, according to research presented at International Stroke Conference.

“Cerebral amyloid angiopathy is a condition characterized by amyloid deposition in the brain’s blood vessels [and] is a common cause of spontaneous intracerebral hemorrhage in older patients,” Cyprien Rivier, MD, MSc, a postdoctoral research fellow in neurology at Yale School of Medicine, and colleagues wrote.

Rivier and fellow researchers sought to determine whether cerebral amyloid angiopathy (CAA) is an independent risk factor for isolated nontraumatic subdural hemorrhage (SDH).

They conducted a two-stage observational study of patients aged older than 55 years, retrospectively analyzing data from UK Biobank in the discovery phase and from All of US in the replication phase. Log-rank tests and multivariable Cox proportional hazards models adjusted for demographic characteristics and vascular risk factors were used for analyses.

Researchers included 283,452 participants in the discovery phase (n = 123 CAA, n = 504 SDH) and 168,370 participants in the replication phase (n = 66 CAA, n = 443 SDH).

According to results, SDH was reported in 2.4% of participants with CAA in the discovery phase compared with 0.2% without CAA. Moreover, a multivariable Cox model demonstrated that CAA was associated with a significantly increased risk for SDH (HR = 7.3; 95% CI, 2.3-22.7), a finding also reported in the replication phase (HR = 11.66; 95% CI, 5.2-26.2).

“CAA was independently associated with a higher risk of isolated nontraumatic SDH,” Rivier and colleagues wrote. “Further research is needed to determine causality and identify biological pathways that may mediate this association.”