Low Incidence of Delayed Intracranial Hemorrhage in Geriatric Emergency Department Patients on Preinjury Anticoagulation Presenting with Blunt Head Trauma

Background Delayed intracranial hemorrhage (ICH) after head injury in older patients taking anticoagulants has been reported to be as high as 7.2%. Other studies suggest much lower rates. Its incidence and clinical management are controversial with some recommending observation and repeat head imaging at 24 hours. Objective Our study aims to assess the incidence of delayed ICH in geriatric Emergency Department (ED) head trauma patients prescribed preinjury anticoagulants. Methods We performed is a prospective cohort study conducted at two hospital EDs from August 2019 to July 2020. All patients aged ≥ 65 years or older with acute head injury were eligible for enrollment. We conducted telephone follow-up occurred at 14 and 60 days and a chart review at 90 days. The primary study outcome was incidence of delayed ICH which was defined as an initial negative head CT followed by subsequent ICH believed to be caused by the initial traumatic event. We compared the rates of delayed ICH between patient cohorts based on anticoagulant use. Results 3,425 patients were enrolled. 2,300 (67.2%) were not on an anticoagulant, 249 (7%) were on preinjury warfarin, 780 (22.7%) on a direct acting oral anticoagulant, and 96 (2.8%) were on enoxaparin or heparin. The median age was 82 years (IQR 65-107), the majority were female (55.2%) and almost all were Caucasian (84.3%). An acute ICH was identified in 229 of 3,425 (6.7%, 95% CI: 6-8%) and delayed ICH in 13 (0.4%, 95% CI: 0.2-0.6%). There were no differences in rates of delayed ICH between those who had been prescribed anticoagulants versus those who had not (p=0.45). Conclusions The incidence of delayed ICH is very low in older ED head trauma patients on prescribed pre-injury anticoagulants. Our data have important clinical implications for the management of blunt head trauma among older ED patients on anticoagulants.