Outcomes among patients with isolated traumatic brain injury before and after Medicaid expansion.

INTRODUCTION

Insurance coverage is a critical determinant of access to care. Uninsured patients suffer poorer outcomes including increased risk of morbidity/mortality. To reduce uninsurance among adults, the Affordable Care Act provisioned states the option to expand Medicaid eligibility. We hypothesized that patients with isolated traumatic brain injury (TBI) had more insurance coverage and better outcomes after Medicaid expansion as compared with before.

METHODS

National data on trauma admissions were obtained from the American College of Surgeons Trauma Quality Program Public Use File for 3 years preceding and following the implementation of Medicaid expansion in 2014. Isolated TBI admissions were identified by an Abbreviated Injury Scale-Head score of ≥2 without significant bodily injury. Only patients between the ages 18 and 64 years were included, as that was the Medicaid expansion target demographic. Univariate and multivariate analyses controlling for injury severity were used to detect changes in insurance coverage (Medicaid, private/other insurance, uninsured), outcomes, and discharge disposition.

RESULTS

There were 267,716 and 313,664 admissions for isolated TBI in pre- and postexpansion years. The proportion of patients insured by Medicaid rose significantly from 13.8% to 22.6% (+8.8%, p < 0.01) in postexpansion years with a concomitant decrease in self-pay/uninsurance (-6.7%, p < 0.01) and private/other insurance (-2.1%, p < 0.01). While there was no significant difference in isolated TBI mortality pre- to postexpansion (3.4% vs. 3.5%, p = 0.18), patients in the postexpansion period were more likely to receive posthospital care at an inpatient facility or via home health service compared with pre-expansion (odds ratio [OR], 1.3; p < 0.01). After controlling for injury severity, patients with Medicaid in the postexpansion period had reduced odds of mortality (OR, 0.6; p < 0.01) and increased rates of posthospital care (OR, 2.1; p < 0.01).

CONCLUSION

Medicaid expansion corresponded to increased Medicaid coverage and a higher rate of posthospital care among adults with isolated TBI. Following expansion, patients with Medicaid were 1.6 times as likely to survive and 2.1 times as likely to be discharged under medical care compared with uninsured patients.

LEVEL OF EVIDENCE: Prognostic and Epidemiological; Level III.