title: Factors affecting mortality in older trauma patients-A systematic review and meta-analysis.
abstract: BACKGROUND
  Major trauma in older people is a significant health burden in the developed world. The aging of the population has resulted in larger numbers of older patients suffering serious injury. Older trauma patients are at greater risk of death from major trauma, but the reasons for this are less well understood. The aim of this review was to identify the factors affecting mortality in older patients suffering major injury.
  
  
  METHODS
  A systematic review of Medline, Cinhal and the Cochrane database, supplemented by a manual search of relevant papers was undertaken, with meta-analysis. Multi-centre cohort studies of existing trauma registries that reported risk-adjusted mortality (adjusted odds ratios, AOR) in their outcomes and which analysed patients aged 65 and older as a separate cohort were included in the review.
  
  
  RESULTS
  3609 papers were identified from the electronic databases, and 28 from manual searches. Of these, 15 papers fulfilled the inclusion criteria. Demographic variables (age and gender), pre-existing conditions (comorbidities and medication), and injury-related factors (injury severity, pattern and mechanism) were found to affect mortality. The 'oldest old', aged 75 and older, had higher mortality rates than younger patients, aged 65-74 years. Older men had a significantly higher mortality rate than women (cumulative odds ratio 1.51, 95% CI 1.37-1.66). Three papers reported a higher risk of death in patients with pre-existing conditions. Two studies reported increased mortality in patients on warfarin (cumulative odds ratio 1.32, 95% CI 1.05-1.66). Higher mortality was seen in patients with lower Glasgow coma scores and systolic blood pressures. Mortality increased with increased injury severity and number of injuries sustained. Low level falls were associated with higher mortality than motor vehicle collisions (cumulative odds ratio 2.88, 95% CI 1.26-6.60).
  
  
  CONCLUSIONS
  Multiple factors contribute to mortality risk in older trauma patients. The relation between these factors and mortality is complex, and a fuller understanding of the contribution of each factor is needed to develop a better predictive model for trauma outcomes in older people. More research is required to identify patient and process factors affecting mortality in older patients.
authors.affiliation: School of Health and Related Research, The University of Sheffield, Regent Court, 30 Regent Street, Sheffield S1 4DA, UK. Electronic address: ian.sammy@sheffield.ac.uk.
authors.forename: Ian
authors.initials: I
authors.lastname: Sammy
authors.affiliation: School of Health and Related Research, The University of Sheffield, Regent Court, 30 Regent Street, Sheffield S1 4DA, UK.
authors.forename: Fiona
authors.initials: F
authors.lastname: Lecky
authors.affiliation: School of Health and Related Research, The University of Sheffield, Regent Court, 30 Regent Street, Sheffield S1 4DA, UK.
authors.forename: Anthea
authors.initials: A
authors.lastname: Sutton
authors.affiliation: School of Health and Related Research, The University of Sheffield, Regent Court, 30 Regent Street, Sheffield S1 4DA, UK.
authors.forename: Joanna
authors.initials: J
authors.lastname: Leaviss
authors.affiliation: School of Health and Related Research, The University of Sheffield, Regent Court, 30 Regent Street, Sheffield S1 4DA, UK.
authors.forename: Alicia
authors.initials: A
authors.lastname: O'Cathain
mesh_terms: D000367:Age Factors; D015897:Comorbidity; D017052:Hospital Mortality; D006801:Humans; D016017:Odds Ratio; D019338:Polypharmacy; D012042:Registries; D012307:Risk Factors; D014193:Trauma Centers / Q000706:statistics & numerical data; D015599:Trauma Severity Indices; D014947:Wounds and Injuries / Q000401:mortality* / Q000628:therapy
keywords: Aged; Co-morbidity; Major trauma; Mortality; Multiple injuries