Differences in the epidemiology of out-of-hospital and in-hospital trauma deaths.

BACKGROUND: Trauma is a leading cause of mortality. Holistic views of trauma systems consider injury as a public health problem that requires efforts in primary, secondary and tertiary prevention. However, the performance of trauma systems is commonly judged on the in-hospital mortality rate. Such a focus misses opportunities to consider all deaths within a population, to understand differences in in-hospital and out-of-hospital trauma deaths and to inform population-level injury prevention efforts. The aim of this study was to provide an epidemiological overview of out-of-hospital and in-hospital trauma deaths in a geographically-defined area over a 10-year period. METHODS: We performed a population-based review of out-of-hospital and in-hospital trauma deaths over the period of 01 July 2006 to 30 June 2016 in Victoria, Australia, using data from the National Coronial Information System and the Victorian State Trauma Registry. Temporal trends in population-based incidence rates were evaluated. RESULTS: Over the study period, there were 11,246 trauma deaths, of which 71% were out-of-hospital deaths. Out-of-hospital trauma deaths commonly resulted from intentional self-harm events (50%) and transport events (35%), while in-hospital trauma deaths commonly resulted from low falls (≤1 metre) (50%). The incidence of overall trauma deaths did not change over the study period (incidence rate ratio 0.998; 95%CI: 0.991, 1.004; P = 0.56). CONCLUSIONS: Out-of-hospital deaths accounted for most trauma deaths. Given the notable differences between out-of-hospital and in-hospital trauma deaths, monitoring of all trauma deaths is necessary to inform injury prevention activities and to reduce trauma mortality. The absence of a change in the incidence of both out-of-hospital and in-hospital trauma deaths demonstrates the need for enhanced activities across all aspects of injury prevention.

Oligoclonal analysis of the atopic T cell response to the group 1 allergen of Cynodon dactylon (bermuda grass) pollen: pre- and post-allergen-specific immunotherapy.

BACKGROUND: Bermuda grass pollen (BGP) is an increasingly important seasonal aeroallergen in Australia and other subtropical and temperate regions. BGP shares minimal allergenic cross-reactivity with pollens of rye grass or other Pooideae grasses often used for desensitization regimens in grass pollen allergy. Current allergen immunotherapy is seldom used in asthmatic patients due to IgE-mediated side effects. Since clinically effective immunotherapy is linked with altered allergen-specific T cell response, characterisation of human T cell reactivity to Cyn d 1, the major B cell allergen of BGP, should permit the design of effective and safe immunotherapy for BGP allergy. METHODS: Short-term BGP-specific CD4+ T cell lines were established from peripheral blood of 14 BGP-sensitive patients before and after conventional 50% BGP and 50% 7-grass mix subcutaneous specific allergen immunotherapy (SIT). T cell diversity of antigen specificity and function was assessed by proliferation and cytokine production to BGP, Cyn d 1 and Cyn d 1 peptides. RESULTS: Three highly immunogenic regions of Cyn d 1 were identified in 13/14 patients pre-SIT: Cyn d 1 (109-128), (181-209) and (217-241). The SIT regimen was clinically efficacious. Following SIT, decreased proliferation to BGP, Cyn d 1 and Cyn d 1 peptides was observed with a marked decrease in the IL-5:IFN-gamma ratio. CONCLUSIONS: Cyn d 1 is a major T cell allergen of BGP. Decreased Cyn d 1-specific IL-5 dominant T cell responses were observed in association with clinically effective treatment with the 50% BGP and 50% 7-grass mix. Identified dominant T cell regions of Cyn d 1 should facilitate safer vaccine development for BGP-induced asthma in addition to rhinitis.