Scandinavian Neurotrauma Guidelines: Frequency of intracranial hemorrhage in patients over 65 years old and on anti-platelet medication.

Purpose: In 2013, the Scandinavian Neurotrauma Committee, produced an evidence-based guideline for the use of Computed Tomography (CT) in patients presenting following recent (<24 h) head injury (HI). A head CT scan is recommended for medium-risk patients with a Glasgow Coma Scale (GCS) score of 14-15, who are > 65 years old and on anti-platelet medication. The aim of this study was to determine the prevalence of intracranial hemorrhage (ICH) on head CT scans in this population, and to test for associations between ICH and baseline characteristics, symptoms and objective clinical findings.

Methods: This register-based retrospective study determined the prevalence of ICH on head CT scans performed over a 1-year period based on written CT-reports. Patient medical charts and imaging records were examined for data on symptomatology, objective findings and comorbidities.

Results: The study population included 325 unique head CT scans with a 5.2% prevalence of ICH. Risk ratios (RR's) signified higher risk of ICH with a GCS score of 14 compared to a GCS score of 15 (RR 5.35, 95%CI 2.14-13.47). ICH risk was lower in patients on Clopidogrel medication compared to Acetylsalicylic Acid medication (RR 0.33, 95%CI 0.12-0.93).

Conclusions: The associations between ICH and the GCS score call attention to the importance of comprehensive clinical examination of HI patients to minimize CT overuse. The implications for patients and healthcare resources in scanning patients > 65 years on anti-platelet medication should be determined by future prospective studies.