title: Injuries before and after diagnosis of cancer: nationwide register based study.
abstract: OBJECTIVE
  To examine the relative risks of iatrogenic and non-iatrogenic injuries during the period shortly before and after a diagnosis of cancer.
  
  
  METHODS
  Nationwide register based study.
  
  
  METHODS
  Swedish national population and health registers.
  
  
  METHODS
  720 901 patients with diagnosis of cancer, 1991-2009, in Sweden.
  
  
  METHODS
  All hospital admissions in patients with cancer with a main discharge diagnosis of iatrogenic (from medical complications) or non-iatrogenic injuries in 1990-2010 identified from the Swedish patient register. Conditional Poisson regression was used to compare the incidence rate of injuries during the "diagnostic period" (16 weeks before to 16 weeks after diagnosis) with the incidence rate during a "pre-diagnostic period" (the same 32 weeks one year before diagnosis) among the same patients.
  
  
  RESULTS
  During the diagnostic period, there were 7306 iatrogenic (incidence rate 0.60 per 1000 person months) and 8331 non-iatrogenic injuries (incidence rate 0.69 per 1000 person months). For iatrogenic injuries, the incidence rate ratio was 7.0 (95% confidence interval 6.6 to 7.4) during the diagnostic period compared with the pre-diagnostic period. The increase in risk started two weeks before cancer diagnosis and peaked during the two weeks after diagnosis (48.6, 37.3 to 63.5). For non-iatrogenic injuries, the incidence rate ratio was 1.9 (1.8 to 2.0) during the diagnostic period compared with the pre-diagnostic period. The increase in risk began four weeks before diagnosis and peaked during the two weeks before diagnosis (5.3, 4.6 to 6.1). There were increased risks of both types of injury during the diagnostic period for all common cancers, with the smallest risk increase noted for non-melanoma skin cancer.
  
  
  CONCLUSIONS
  Patients with cancer have highly increased risks of both iatrogenic and non-iatrogenic injuries requiring inpatient care : shortly before and after their diagnosis. These findings shed further light on the total burden of medical complications and call for prevention of intentional and unintentional injuries during the diagnostic process of cancer.
authors: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, SE-171 77 Stockholm, Sweden qing.shen@ki.se.
authors: Qing
authors: Q
authors: Shen
authors: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
authors: Donghao
authors: D
authors: Lu
authors: Epidemiology and Register Centre South, Region Skåne, SE-221 85 Lund, Sweden Unit of Cardiovascular Disease, Institute of Environmental Medicine, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
authors: Maria E C
authors: ME
authors: Schelin
authors: Epidemiology and Register Centre South, Region Skåne, SE-221 85 Lund, Sweden Division of Occupational and Environmental Medicine, Department of Laboratory Medicine Lund, Lund University, SE-221 00 Lund, Sweden.
authors: Anna
authors: A
authors: Jöud
authors: Unit of Biostatistics, Institute of Environmental Medicine, Karolinska Institutet, SE-171 77 Stockholm, Sweden Clinical Epidemiology and Biostatistics, School of Medical Sciences, Örebro University, SE-701 82 Örebro, Sweden.
authors: Yang
authors: Y
authors: Cao
authors: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, SE-171 77 Stockholm, Sweden Institute of Health and Society, University of Oslo, NO-0316 Oslo, Norway Department of Epidemiology, Harvard T.H. Chan School of Public Health, MA-02115 Boston, USA.
authors: Hans-Olov
authors: HO
authors: Adami
authors: Clinical Epidemiology Unit, Department of Medicine Solna, Karolinska University Hospital, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
authors: Sven
authors: S
authors: Cnattingius
authors: Clinical Epidemiology and Biostatistics, School of Medical Sciences, Örebro University, SE-701 82 Örebro, Sweden.
authors: Katja
authors: K
authors: Fall
authors: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, SE-171 77 Stockholm, Sweden Department of Epidemiology, Harvard T.H. Chan School of Public Health, MA-02115 Boston, USA Center of Public Health Sciences, Faculty of Medicine, University of Iceland, IS-101 Reykjavík, Iceland.
authors: Unnur
authors: U
authors: Valdimarsdóttir
authors: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
authors: Fang
authors: F
authors: Fang
mesh_terms: D000059:Accidents / Q000706:statistics & numerical data; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006760:Hospitalization; D006801:Humans; D007049:Iatrogenic Disease / Q000453:epidemiology*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000175:diagnosis*; D012042:Registries; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors; D014947:Wounds and Injuries / Q000453:epidemiology*