Effect of diabetes mellitus on outcome in patients with traumatic brain injury: A national trauma databank analysis

Abstract

Background: Diabetes mellitus (DM) is associated with worsened outcomes following severe injury. However, clinical studies evaluating the effect of DM on outcomes in patients suffering traumatic brain injury (TBI) are currently lacking.

Methods: This was a National Trauma Databank (NTDB) study over a 5-year period. Patients with DM were matched with victims of isolated TBI without DM in a 1:2 ratio. Outcomes included mortality, hospital and surgical intensive care unit (SICU) length of stay, ventilator days and discharge disposition.

Results: Of the 35 005 patients with isolated TBI, 636 (1.8%) cases had documented DM. After matching 1272 counterparts without DM, no differences with regards to demographic and injury characteristics were observed comparing the two groups. Overall mortality in the study population was 18.8% (n = 358), with a significantly increased in-hospital mortality in patients with vs without DM [22.6% vs 16.8%; OR (95% CI): 1.45 (1.14–1.83); p = 0.002]. Patients with DM were significantly less frequently discharged home compared to their counterparts without DM [38.9% vs 46.1%; OR (95% CI): 0.75 (0.60–0.93); p = 0.008].

Conclusion: Traumatic brain injury in conjunction with diabetes mellitus is associated with an almost 1.5-fold increased mortality while compared to patients with isolated TBI without diabetes mellitus. Prospective validation of these findings is warranted to determine the underlying aetiology.

• Diabetes mellitus
• head injury
• traumatic brain injury
• outcome
• mortality

Declaration of Interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.