Impact of Concomitant Injuries on Clinical Outcomes in Patients with Isolated versus Non-Isolated Traumatic Brain Injury.

Objective: Traumatic brain injury (TBI) often occurs alongside injuries to other body regions, worsening patient outcomes. This study aimed to evaluate the impact of concomitant injuries on clinical outcomes in patients with isolated versus non-isolated TBI.

Method: A retrospective cross-sectional analysis was conducted using data from the Emergency Department-based Injury In-depth Surveillance System (EDIIS), encompassing 180,058 TBI patients admitted to 23 tertiary hospitals from January 1, 2020, to December 31, 2022. Patients were categorized into isolated TBI (iTBI, n = 127,673) and non-isolated TBI (niTBI, n = 52,385) groups based on injury diagnostic codes. Clinical outcomes-including 24-hour and 30-day mortality, hospital admission, and interhospital transfer-were compared. Multivariate logistic regression analyses adjusted for potential confounders were performed.

Result: niTBI patients exhibited significantly higher 24-hour mortality (1.5% vs. 0.4%), 30-day mortality (2.6% vs. 1.0%), hospital admissions (24.5% vs. 8.4%), and interhospital transfers (3.6% vs. 1.1%) compared to iTBI patients (all p < 0.001). Concomitant injuries increased the adjusted odds of 24-hour mortality (aOR = 1.456; 95% CI: 1.286-1.648) and 30-day mortality (aOR = 1.111; 95% CI: 1.022-1.208). Thoracic injuries were the most significant predictor of adverse outcomes in niTBI patients, nearly sixfold increasing the odds of 24-hour mortality (aOR = 5.958; 95% CI: 5.057-7.019).

Conclusions: Concomitant injuries significantly worsen clinical outcomes in TBI patients, with thoracic injuries being the most critical predictor of mortality. These findings highlight the importance of comprehensive trauma assessment and targeted prevention strategies to improve survival rates and optimize resource allocation for patients with multiple injuries.