Incidence and risk factors of delayed intracranial hemorrhage in the emergency department

Objectives: This study was performed to identify the risk factors for delayed intracranial hemorrhage and develop a risk stratification system for disposition of head trauma patients with negative initial brain imaging. Methods: The data source was National Health Insurance Service-National Sample Cohort of Korea. We analyzed adult patients presenting to the ER from January 2004 to September 2012, who underwent brain imaging and discharged with or without short-term observation no longer than two days. The primary outcome was defined as any intracranial bleeding within a month defined by a new appearance of any of the diagnostic codes for intracranial hemorrhage accompanied by a new claim for brain imaging(s) within a month of the index visit. We performed amultivariable logistic regression analysis and built a parsimoniousmodel for variable selection to develop a simple scoring system for risk stratification. Results: During the study period, a total of 19,723 head injury cases were identified from the cohort and a total of 149 cases were identified as having delayed intracranial hemorrhage within 30 days. In multivariable logistic regression model, old age, craniofacial fracture, neck injury, diabetes mellitus and hypertension were independent risk factors for delayed intracranial hemorrhage. We constructed the parsimonious model included age, craniofacial fracture and diabetes mellitus. The score showed area under the curve of 0.704 and positive predictive value of the score system was 0.014 when the score >= 2. Conclusions: We found old age, associated craniofacial fracture, any neck injury, diabetes mellitus and hypertension are the independent risk factors of delayed intracranial hemorrhage. (C) 2017 Published by Elsevier Inc.