Researchers found that patients older than 60 years with unruptured brain arteriovenous malformations (AVMs) had a twofold higher risk of intracranial hemorrhage (ICH) compared with those diagnosed before age 20. Among 3,030 patients followed for a median of 3.7 years, the annual ICH risk was 1.4 per 100 person-years—lower than prior estimates of 2% to 4%. Independent predictors of first hemorrhage included advanced age, flow-associated arterial aneurysms, and cerebellar or deep supratentorial AVM location. Each additional risk factor increased hemorrhage risk by 65%.

Source: JAMA Neurology