Does health care insurance affect outcomes after traumatic brain injury? Analysis of the National Trauma Databank.

Increasing evidence indicates insurance status plays a role in the outcome of trauma patients; however its role on outcomes after traumatic brain injury (TBI) remains unclear. A retrospective review was queried within the National Trauma Data Bank. Moderate to severe TBI insured patients were compared with their uninsured counterparts with respect to demographics, Injury Severity Score, Glasgow Coma Scale score, and outcome. Multivariate logistic regression analysis was used to determine independent risk factors for mortality. Of 52,344 moderate to severe TBI patients, 41,711 (79.7%) were insured. Compared with the uninsured, insured TBI patients were older (46.1 +/- 22.4 vs. 37.3 +/- 16.3 years, P < 0.0001), more severely injured (ISS > or =16: 78.4% vs. 74.4%, P < 0.0001), had longer intensive care unit length of stay (6.0 +/- 9.4 vs. 5.1 +/- 7.6, P < 0.0001) and had higher mortality (9.3% vs. 8.0%, P < 0.0001). However, when controlling for confounding variables, the presence of insurance had a significant protective effect on mortality (adjusted odds ratio 0.89; 95% confidence interval: 0.82-0.97, P = 0.007). This effect was most noticeable in patients with head abbreviated injury score = 5 (adjusted odds ratio 0.7; 95% confidence interval: 0.6-0.8, P < 0.0001), indicating insured severe TBI patients have improved outcomes compared with their uninsured counterparts. There is no clear explanation for this finding however the role of insurance in outcomes after trauma remains a topic for further investigation.