Correlation between Head Trauma and Outcome of Chronic Subdural Hematoma

OBJECTIVE Our study examined the prognostic factors involved in the outcome of patients with chronic subdural hematoma (CSDH) who had undergone burr hole drainage procedures, and investigated the association between outcome and traumatic head injury. In addition, we explored factors related to recurrence. METHODS This study enrolled 238 patients with CSDH who had undergone burr hole drainage. Patients with history of head injury were categorized into the head trauma group and were compared with the no head trauma group. Outcome was considered good when modified Rankin Scale scores improved from admission to discharge and the final follow-up. RESULTS Among 238 patients, 127 (53.4%) were included in the head trauma group. One hundred thirty-three (55.9%) patients demonstrated good outcome at discharge, and 171 (71.8%) patients demonstrated good outcome at the final follow-up. None of the factors examined was significantly correlated with good outcome at discharge. However, only history of head injury (p=0.033, odds ratio 0.511, 95% confidence interval 0.277-0.946) was significantly correlated with poor outcome at long-term follow-up. Recurrence occurred in 20 (8.4%) cases in the total cohort and 11 (55%) patients in the head trauma group. CONCLUSION History of head trauma is correlated with poor outcome at long-term follow-up in CSDH patients having undergone burr hole drainage. Therefore, CSDH patients with history of head injury are susceptible to poor outcome, warranting more careful evaluation and treatment after burr hole drainage.