Relationship of Insurance Status to Hospital Length of Stay after Traumatic Injury: Patients with Publically Funded Insurance Have the Longest Lengths of Stay and Uninsured Patients Are Discharged the Earliest

Abstract

Introduction: Research has consistently shown that insurance status significantly impacts health care, including resource use, morbidity, and mortality. Data from several medical specialties demonstrate that patients without insurance have fewer physician visits, receive fewer procedures, and have shorter lengths of hospital stay leading to worse clinical outcomes. Uninsured hospitalized trauma patients are also known to have worse mortality outcomes; however, the impact of insurance on hospital stay in trauma is unknown. Objective: To examine the impact of insurance status on hospital length of stay (LOS) in the setting of acute trauma. Methods: Trauma patients, age 18-64, included in the National Trauma Data Bank (NTDB) between 2002-2006 were analyzed. Patients were categorized in three insurance groups: 1) Private insurance (HMO, PPO, MCO, Workers Comp, No Fault, and other commercial plans), 2) Publically funded insurance (Medicaid & Medicare), and 3) Uninsured (self pay or private charity). In unadjusted analyses Student's t-test were applied to determine the bi-variate relationship between insurance and LOS. In order to control for differences in injury severity and case mix between insurance groups, generalized linear models, an extension of multiple linear regression, were used, and adjusted estimates of LOS calculated. Covariates adjusted for included: age, gender, race, injury severity score (ISS), presence of shock (SBP<90) on ED arrival, GCS motor score, mechanism of injury (motor vehicle collision, motorcycle collision, fall, etc), type of injury (blunt vs. penetrating), intention of injury, presence of severe head and/or extremity injury, and year of admission. Results: 542,171 patients in the NTDB met inclusion criteria and had complete data for analysis. Unadjusted median hospital LOS for Uninsured patients was 2 days. Private and Publically insured patients had a median LOS of 3 days (respective mean LOS: 4.4, 5.3, and 6.9, p<0.001). After adjusting for covariates, mean length of stay for Uninsured patients was the lowest followed by Private insurance and then Publically insured patients (see figure). On analysis of patients with moderate to severe injuries (ISS>9), LOS for Uninsured, Privately insured, and Publically insured patients were 12.7, 13.5, and 15.7 days, respectively. Similarly among the most severely injured patients (ISS>15), the respective LOS were 13.3, 14.6, and 17.7 days. The differences between adjusted LOS for each insurance group were significant (p<0.001) across all injury severities. Conclusion: The ability to pay is directly linked to length of hospital stay in acute trauma patients. Those without insurance are discharged the earliest whereas those with publically funded insurance are kept in hospital the longest. These disparities in LOS are even more pronounced among the more severely injured patients with even longer hospital stays. These data become increasingly important given the current debate over health care reform. As a next step towards improving health care disparities after trauma, the relationship between LOS, quality of care, and outcomes needs to be further explored.