Incidence of Chronic Subdural Hematoma after Mild Head Trauma in Elderly Patients with or without Pre-traumatic Conditioning of Anti-thrombotic Drugs

]Abstract] Anti-thrombotic drugs may increase the risk for chronic subdural hematoma (CSDH). However, whether to continue or discontinue/counteract these drugs has not been investigated in patients with mild head trauma. CSDH incidence after mild head trauma, as well as the risk for CSDH in patients with anti-thrombotic drugs, were investigated in this study. The study included 765 consecutive elderly (>65 y.o.) patients with mild head trauma and an initial Glasgow Coma Scale (GCS) score of 14 or 15. All patients received initial CT within 24 hours after trauma and were re-examined 30 days after trauma to detect CSDH formation, repeating for every 30 days to examine symptomatic CSDH progression. Patients were divided into two groups, with anti-thrombotic drugs (n=195) or without them (n=263), to investigate the influence of pre-traumatic conditioning with anti-thrombotic drugs on CSDH. The whole sample was 458 out of 765 cases. The incidence of CSDH formation was 91 out of 458 cases (19.9%) after mild head trauma, with no significant difference between with and without anti-thrombotic drugs. CSDH progressed as symptomatic in 21 out of 458 cases (4.6%), with no significant difference between with and without anti-thrombotic drugs. Pre-traumatic conditioning with anti-thrombotic drugs and its continuation after trauma did not affect the incidence of formation or symptomatic progression of CSDH. This finding suggests that discontinuing and/or counteracting anti-thrombotic drugs may be unnecessary in patients with mild head trauma.