Understanding the risk factors of trauma center closures: do financial pressure and community characteristics matter?

OBJECTIVES We analyze whether hazard rates of shutting down trauma centers are higher due to financial pressures or in areas with vulnerable populations (such as minorities or the poor). MATERIALS AND METHODS This is a retrospective study of all hospitals with trauma center services in urban areas in the continental US between 1990 and 2005, identified from the American Hospital Association Annual Surveys. These data were linked with Medicare cost reports, and supplemented with other sources, including the Area Resource File. We analyze the hazard rates of trauma center closures among several dimensions of risk factors using discrete-time proportional hazard models. RESULTS The number of trauma center closures increased from 1990 to 2005, with a total of 339 during this period. The hazard rate of closing trauma centers in hospitals with a negative profit margin is 1.38 times higher than those hospitals without the negative profit margin (P < 0.01). Hospitals receiving more generous Medicare reimbursements face a lower hazard of shutting down trauma centers (ratio: 0.58, P < 0.01) than those receiving below average reimbursement. Hospitals in areas with higher health maintenance organizations penetration face a higher hazard of trauma center closure (ratio: 2.06, P < 0.01). Finally, hospitals in areas with higher shares of minorities face a higher risk of trauma center closure (ratio: 1.69, P < 0.01). Medicaid load and uninsured populations, however, are not risk factors for higher rates of closure after we control for other financial and community characteristics. CONCLUSIONS Our findings give an indication on how the current proposals to cut public spending could exacerbate the trauma closure particularly among areas with high shares of minorities. In addition, given the negative effect of health maintenance organizations on trauma center survival, the growth of Medicaid managed care population should be monitored. Finally, high shares of Medicaid or uninsurance by themselves are not independent risk factors for higher closure as long as financial pressures are mitigated. Targeted policy interventions and further research on the causes, are needed to address these systems-level disparities.