Risk factors for recurrent neurotrauma: a population-based study in Southeastern Michigan.

INTRODUCTION: Studies have shown an increased risk of traumatic brain injury (TBI) for individuals who suffer an initial TBI. The current study hypothesized that individuals with recurrent neurotrauma would originate from populations considered 'vulnerable', i.e. low income and/or with psychiatric comorbidities. METHODS: Data from the Michigan State Inpatient Database from 2006 to 2014 for the Detroit metropolitan area enlisted a study population of 50 744 patients with neurotrauma. Binary logistic regression was used to assess risk factors associated with admission for subsequent neurotrauma compared with single neurotrauma admission. RESULTS: Patients with repeated neurotrauma admissions were similar to those with one-time trauma in terms of age at first admission and neighbourhood income levels. However, patients with repeated neurotrauma admissions were more likely to be male (p < .001) and African-American (p < .001). Comorbid alcohol use and drug use were 39% and 15% less likely to be readmitted with neurotrauma, respectively. Comorbid conditions associated with greater risk of repeat neurotrauma included depression, psychosis, and neurological disorders, increasing risk by 38%, 22%, and 58%, respectively. CONCLUSION: This study validated the hypothesis that comorbid psychiatric conditions are a significant risk factor for recurrent neurotrauma and validate prior studies showing gender and race as significant risk factors.

Between-hospital and between-neighbourhood variance in trauma outcomes: cross-sectional observational evidence from the Detroit metropolitan area.

OBJECTIVE: Disparities in treatment outcomes for traumatic injury are an important concern for care providers and policy makers. Factors that may influence these disparities include differences in risk exposure based on neighbourhood of residence and differences in quality of care between hospitals in different areas. This study examines geographical disparities within a single region: the Detroit metropolitan area. DESIGN: Data on all trauma admissions between 2006 and 2014 were obtained from the Michigan State Inpatient Database. Admissions were grouped by patient neighbourhood of residence and admitting hospital. Generalised linear mixed modelling procedures were used to determine the extent of shared variance based on these two levels of categorisation on three outcomes. Patients with trauma due to common mechanisms (falls, firearms and motor vehicle traffic) were examined as additional subgroups. SETTING: 66 hospitals admitting patients for traumatic injury in the Detroit metropolitan area during the period from 2006 to 2014. PARTICIPANTS: 404 675 adult patients admitted for treatment of traumatic injury. OUTCOME MEASURES: In-hospital mortality, length of stay and hospital charges. RESULTS: Intraclass correlation coefficients indicated that there was substantial shared variance in outcomes based on hospital, but not based on neighbourhood of residence. Among all injury types, hospital-level differences accounted for 12.5% of variance in mortality risk, 28.5% of variance in length of stay and 32.2% of variance in hospital charges. Adjusting the results for patient age, injury severity, mechanism and comorbidities did not result in significant reduction in the estimated variance at the hospital level. CONCLUSIONS: Based on these data, geographical disparities in trauma treatment outcomes were more strongly attributable to differences in access to quality hospital care than to risk factors in the neighbourhood environment. Transfer of high-risk cases to hospitals with greater institutional experience in the relevant area may help address mortality disparities in particular.