title: Burden of bloodstream infection in an area of Mid-Norway 2002-2013: a prospective population-based observational study.
abstract: Studies from several countries indicate that the incidence and mortality of bloodstream infection (BSI) have been increasing over time.
  
  
  
  We studied the burden of disease and death related to BSI in a defined geographical area of Mid-Norway, where BSI episodes were prospectively recorded by the same microbiological department during 12 consecutive years. Death from BSI was defined as death within 30 days of BSI detection. Age and sex standardized incidence and mortality rates and case fatality rates were calculated.
  
  
  
  Between 2002 and 2013, 1995 episodes of BSI in 1719 patients aged 16 to 99 years were included. The overall incidence of BSI was 215 per 100,000 person-years. The incidence increased exponentially with age, particularly in males. The incidence increased from 205 to 223 per 100,000 person-years from 2002-07 to 2008-13. Escherichia coli was the most frequently isolated infective agent, followed by Streptococcus pneumoniae and Staphylococcus aureus. The rate of S. pneumoniae BSI decreased over time in males (on average by 9.2% annually), but not in females. The total rate of BSI microbes with acquired resistance increased slightly over time, but did not exceed 2 episodes per 100,000 person-years. The mortality of BSI was 32 per 100,000 person-years, higher in males than in females (36 vs. 28 per 100,000 person-years) and was significantly higher in old age, particularly in males. The total BSI mortality was similar in the first and second halves of the study period, but the mortality of S. pneumoniae BSI decreased in males (15.0% annually). The crude case fatality decreased from the first to the second half of the study period (17.2% to 13.1%; p = 0.014). The rate of blood culture sampling increased more than twofold during the study period.
  
  
  
  The mortality of BSI remained stable during 2002-2013. At the same time, BSI incidence increased and case fatality rate decreased, perhaps because an increased rate of blood culture sampling may have led to improved detection of milder BSI episodes. Very low, yet slightly increasing rates of microbes with acquired resistance were observed.
authors.affiliation: Department of Medicine, Levanger Hospital, Nord-Trøndelag Hospital Trust, post box 333, Levanger, N-7601, Norway. arne.mehl@hnt.no.|Unit for Applied Clinical Research, Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway. arne.mehl@hnt.no.|Mid-Norway Sepsis Research Group, Faculty of Medicine, NTNU, Trondheim, Norway. arne.mehl@hnt.no.
authors.forename: Arne
authors.identifier: 0000-0001-6711-0333
authors.initials: A
authors.lastname: Mehl
authors.affiliation: Mid-Norway Sepsis Research Group, Faculty of Medicine, NTNU, Trondheim, Norway.|Department of Public Health and General Practice, Norwegian University of Science and Technology, Trondheim, Norway.|Department of Endocrinology, St Olav's Hospital, Trondheim University Hospital, Trondheim, Norway.
authors.forename: Bjørn Olav
authors.initials: BO
authors.lastname: Åsvold
authors.affiliation: Regional Centre for Child and Youth Mental Health and Child Welfare - Central Norway, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: Stian
authors.initials: S
authors.lastname: Lydersen
authors.affiliation: Department of Medicine, Levanger Hospital, Nord-Trøndelag Hospital Trust, post box 333, Levanger, N-7601, Norway.|Mid-Norway Sepsis Research Group, Faculty of Medicine, NTNU, Trondheim, Norway.|Centre of Molecular Inflammation Research, Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: Julie
authors.initials: J
authors.lastname: Paulsen
authors.affiliation: Mid-Norway Sepsis Research Group, Faculty of Medicine, NTNU, Trondheim, Norway.|Clinic of Anaesthesia and Intensive Care, St Olav's Hospital, Trondheim University Hospital, Trondheim, Norway.|Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: Erik
authors.initials: E
authors.lastname: Solligård
authors.affiliation: Mid-Norway Sepsis Research Group, Faculty of Medicine, NTNU, Trondheim, Norway.|Centre of Molecular Inflammation Research, Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway.|Department of Infectious Diseases, St Olav's Hospital, Trondheim University Hospital, Trondheim, Norway.
authors.forename: Jan Kristian
authors.initials: JK
authors.lastname: Damås
authors.affiliation: Department of Research and Development, Haukeland University Hospital, Bergen, Norway.|Department of Clinical Science, University of Bergen, Bergen, Norway.
authors.forename: Stig
authors.initials: S
authors.lastname: Harthug
authors.affiliation: Unit for Applied Clinical Research, Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway.|Department of Surgery, Levanger Hospital, Nord-Trøndelag Hospital Trust, Levanger, Norway.
authors.forename: Tom-Harald
authors.initials: TH
authors.lastname: Edna
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016470:Bacteremia / Q000453:epidemiology* / Q000382:microbiology / Q000401:mortality; D001800:Blood Specimen Collection / Q000706:statistics & numerical data; D024881:Drug Resistance, Bacterial; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology / Q000401:mortality; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D011008:Pneumococcal Infections / Q000453:epidemiology / Q000382:microbiology / Q000401:mortality; D011446:Prospective Studies; D013203:Staphylococcal Infections / Q000453:epidemiology; D013211:Staphylococcus aureus / Q000302:isolation & purification / Q000472:pathogenicity; D013296:Streptococcus pneumoniae / Q000302:isolation & purification / Q000472:pathogenicity; D055815:Young Adult
keywords: Bacteraemia; Bacteremia; Bloodstream infection; Case fatality; Incidence; Mortality; Population-based; Sepsis