Risk Factors and Prediction Model for Chronic Subdural Hematoma After Mild TBI in Elderly

Overview

This study evaluated risk factors for chronic subdural hematoma (CSDH) development following mild traumatic brain injury (TBI) in adults aged 65 and older. Using electronic health records from a large Israeli medical center and insurer, a validated prediction model was derived to stratify patients by CSDH risk within 12 weeks post-injury.

Background

Traumatic brain injury (TBI) is a significant public health issue, with older adults experiencing the highest rates of TBI-related emergency visits. Mild TBI constitutes the majority of cases, often with normal initial CT scans, but some patients develop complications such as chronic subdural hematoma (CSDH). The incidence of CSDH is increasing globally, partly due to aging populations and widespread use of antithrombotic medications. Despite this, no validated clinical tools currently exist to predict which elderly patients with mild TBI will develop CSDH.

Data Highlights

The study included patients aged 65 and older presenting with mild TBI (GCS 14–15) at Soroka University Medical Center between 2000 and 2021, insured by Clalit Health Services. CSDH was defined as occurring 2–12 weeks post-injury, confirmed by CT or surgical evacuation. Predictors analyzed included demographics, comorbidities, antithrombotic use, and pathological CT findings at index TBI. Statistical analysis employed multivariable logistic regression with generalized estimating equations to account for repeated events.

Key Findings

• Older age and male sex were associated with increased risk of developing CSDH after mild TBI.
• Use of antithrombotic agents (antiplatelets and anticoagulants) prior to injury significantly elevated CSDH risk.
• Pathological findings on initial head CT, such as intracranial hematomas or skull fractures, were strong predictors of subsequent CSDH.
• Comorbidities including diabetes, ischemic heart disease, hypertension, renal failure, dyslipidemia, and atrial fibrillation were evaluated but specific associations were not detailed in the summary.
• The derived prediction model demonstrated validity for bedside risk stratification of elderly patients with mild TBI.

Clinical Implications

Clinicians should consider age, sex, antithrombotic medication use, and initial CT abnormalities when assessing elderly patients with mild TBI for CSDH risk. Early identification of high-risk individuals may guide monitoring strategies and timely interventions to mitigate poor long-term outcomes. The validated prediction model offers a practical tool to support clinical decision-making in this population.

Conclusion

This study identifies key risk factors for CSDH following mild TBI in older adults and provides a validated prediction model to stratify risk. These findings can enhance clinical assessment and improve management of elderly patients after mild head trauma.

References

1. Centers for Disease Control and Prevention 2014 -- TBI-related Emergency Department Visits
2. Soroka University Medical Center and Clalit Health Services Study -- Risk Factors and Prediction Model for CSDH
3. Recent Studies on CSDH Outcomes -- Functional, Mental, and Cognitive Impact