title: Trauma recidivism at an emergency department of a Swedish medical center.
abstract: BACKGROUND
  To inform targeted prevention, we studied patterns of trauma recidivism and whether a first injury predicts the risk for a recurrent injury.
  
  
  METHODS
  In a population-based study of 98,502 adult injury events 1999-2012, at the emergency department of Umeå University Hospital, Sweden, we compared non-recidivists with recidivists in terms of patients' sex, age, type of injury and severity of the injury.
  
  
  RESULTS
  Thirty-six percent of all patients suffered recurrent injuries, which were associated with a higher proportion of inpatient care and more hospital days. Young men and elderly women were at the highest risk for trauma recidivism. At 20 to 24 years, men had a 2.4 (CI 95 % 2.3-2.5) higher risk than women, a 90 years old woman had almost a 10-fold higher risk for another moderate/severe injury than a 20 years old one. A fracture were associated with a hazard ratio of 1.28 (CI 95 % 1.15-1.42) among men younger than 65 years and 1.31 (CI 95 % 1.12-1.54) for men older than 65 years for a subsequent moderate/severe injury. For women younger than 65 years a fracture was associated with a hazard ratio of 1.44 (CI 95 % 1.28-1.62) for a subsequent moderate/severe injury. A sprain carries a higher risk for a new moderate/severe injury for both men and women and in both age groups; the hazard ratio was 1.13 (CI 95 % 1.00-1.26) for men younger than 65 years, 1.42 (CI 95 % 1.01-1.99) for men older than 65 years, 1.19 (CI 95 % 1.05-1.35) for women younger than 65 years and 1.26 (CI 95 % 1.02-1.56) for women older than 65 years. A higher degree of injury severity was associated with a higher risk for a new moderate/severe injury.
  
  
  CONCLUSIONS
  Trauma recidivism is common and represents a large proportion of all injured. Age and sex are associated with the risk for new injury. Injury types and severity, also have implications for future injury.
authors.affiliation: Division of Surgery and Perioperative Sciences, Department of Orthopaedics, Umea University, 90187, Umea, Sweden. Fredrik.roding@gmail.com.
authors.forename: Fredrik
authors.identifier: http://orcid.org/0000-0002-5832-7087
authors.initials: F
authors.lastname: Röding
authors.affiliation: Department of Public Health and Clinical Medicine, Epidemiology and Global Health, Umea University, 90187, Umea, Sweden.|Umea School of Business and Economics, Department of Statistics, Umea University, 90187, Umea, Sweden.
authors.forename: Marie
authors.initials: M
authors.lastname: Lindkvist
authors.affiliation: Division of Surgery and Perioperative Sciences, Department of Orthopaedics, Umea University, 90187, Umea, Sweden.
authors.forename: Ulrica
authors.initials: U
authors.lastname: Bergström
authors.affiliation: Division of Surgery and Perioperative Sciences, Department of Orthopaedics, Umea University, 90187, Umea, Sweden.
authors.forename: Olle
authors.initials: O
authors.lastname: Svensson
authors.affiliation: Division of Surgery and Perioperative Sciences, Department of Orthopaedics, Umea University, 90187, Umea, Sweden.|Department of Public Health and Clinical Medicine, Epidemiology and Global Health, Centre of Quality Registries North Sweden, Umea University, 90187, Umea, Sweden.
authors.forename: Jack
authors.initials: J
authors.lastname: Lysholm
keywords: Descriptive epidemiology; Longitudinal; Recidivism; Trauma