Does Discontinuation of Aspirin Treatment Following Head Trauma Decrease the Incidence of Chronic Subdural Hematoma?

Anti-aggregation therapy, including treatment with low-dose aspirin (LDA) is an established risk factor for intracranial hemorrhage, including chronic subdural hematoma (CSDH); however evidence guiding the decision to continue or discontinue LDA in patients who have sustained mild head trauma with no sign of injury on CT is lacking. The investigators aim to assess whether continued aspirin treatment increases the risk of CSDH in mild head trauma patients 50 years and older who present with negative head CT. The investigators further aim to use the initial findings to refine the study design, with the goal of performing a larger, multi-institutional study in the future.

Over a 12-month period, approximately 100 patients ≥50 years of age on LDA prophylaxis presenting to Hadassah's Emergency Department after sustaining mild head injury, will be examined by the neurosurgeon on call. Those who have no sign of intracranial hemorrhage at clinical or CT examination, and who meet inclusion / exclusion criteria, will be invited to participate in a randomized study. Informed consent will be obtained. Patients will be remotely randomized for continuation or cessation of LDA treatment. Follow-up CT and clinical examination will be performed 3-5 weeks after trauma.

The two-proportions test will be used to assess whether there is a statistically significant difference in the rate of CSDH in patients randomized to cessation of LDA therapy and those randomized to continuation of LDA. Relationships between the explanatory the dependent variables will be explored with classical parametric and nonparametric statistical methods, including multivariate analysis, logistic regression, the two proportions test, and the independence test. Several measures of association/correlation between pairs of variables will be analyzed as well.

The investigators hypothesize that continuation of LDA will not be associated with increased risk for chronic subdural hematoma, and that cessation of treatment will not be associated with a decrease in chronic subdural hematoma. The investigators further hypothesize that cessation of LDA for this period will not be associated with increased risk for clinically significant cerebrovascular, cardiovascular, thrombotic, of embolic event.