Hospital admission of older patients with mild traumatic brain injury and traumatic intracranial hemorrhage: is it always necessary?

Background and importance: Traumatic intracranial hemorrhage (tICH) after mild traumatic brain injury (mTBI) is not uncommon in the elderly. Often, these patients are admitted to the hospital for observation. The necessity of admission in the absence of clinically important intracranial injuries is however unclear.

Objectives: The objective of this study is to identify which factors additional to tICH affect the risk of this outcome and to evaluate the differences in the risk of adverse outcome in younger and older mTBI patients with tICH.

Design, setting, and participants: This retrospective study assessed adult (≥ 16 years) mTBI patients with tICH admitted to a Level 1 trauma center between January 2017 and October 2020.

Outcome measures and analysis: Patients were stratified into two groups, age < 65 years and age ≥ 65 years. Adverse outcome due to tICH was assessed using a composite adverse outcome which comprised either, a drop in GCS by more than 1 point, progression of or new neurological deficits, seizure activity, progression of tICH on repeated neuroimaging after clinical deterioration, a neurosurgical intervention, a readmission within three months of injury related to TBI, or death. Logistic regression analysis was used to identify independent predictors of the composite adverse outcome.

Main results: In total, 332 mTBI patients with tICH were enrolled in our study. Older mTBI patients with tICH met the criteria for the composite adverse outcome significantly more often than younger patients (12.6% 95% CI 8.0-17.0% vs. 4.9%, 95% CI 1.0-9.0%, p = 0.033). The univariate analysis showed that a neurological deficit (OR 6.55, 95% CI 2.37-18.08) or a SDH on admission (OR 3.13, 95% CI 1.40-6.99) was positively associated with the composite adverse outcome in older patients. The presence of isolated traumatic SAH (tSAH) was associated with a decreased risk of the composite adverse outcome (OR 0.10, 95% CI 0.01-0.71). Multivariate analysis was not possible.

Conclusion: Serious adverse outcomes are frequently observed in older mTBI patients with tICH. Nonetheless, our findings suggest that older patients with an isolated tSAH are at low-risk for deterioration and may be directly discharged from the ED after a short period of observation.