Lack of Health Insurance Associated With Lower Probability of Head Computed Tomography Among United States Traumatic Brain Injury Patients.

BACKGROUND: Uninsured traumatic brain injury (TBI) patients have higher mortality than their insured counterparts. One possible reason is disparities in receipt of appropriate diagnostic imaging.

OBJECTIVE: Examine the association between lack of insurance and use of diagnostic imaging.

RESEARCH DESIGN: This is a retrospective cohort study.

SUBJECTS: All adult patients admitted with severe (AIS>4 and GCS<15) TBI, in the National Trauma Data Bank 2010-2015.

MEASURES: Primary outcome was receipt of head computed tomography (CT) and number of CT scans received. Secondary outcomes included head x-ray, angiography, or magnetic resonance imaging. Patients were classified as uninsured if their payment method was self-pay or not billed.

RESULTS: Of 59,540 patients meeting inclusion criteria, 18.9% were uninsured. After adjusting for demographic, clinical, and facility characteristics, compared with patients with any insurance, 4.47 per 100 (95% confidence interval, 1.60-7.34) fewer uninsured patients had a head CT, with uninsured patients receiving 13% (95% confidence interval, 3-21) fewer head CTs. There were no differences in x-ray, angiography, or magnetic resonance imaging receipt.

CONCLUSIONS: Findings suggest lower receipt of guideline-indicated head CT among uninsured TBI patients. Mechanisms could include unconscious provider bias or institutional financial constraints. Further research is warranted to elucidate mechanisms and assess mediation by diagnostic imaging use of the insurance-mortality association.