Intensive Care Medicine

, Volume 44, Issue 8, pp 1276–1283 | Cite as

Association of iron status with the risk of bloodstream infections: results from the prospective population-based HUNT Study in Norway

  • Randi Marie MohusEmail author
  • Julie Paulsen
  • Lise Gustad
  • Åsa Askim
  • Arne Mehl
  • Andrew T. DeWan
  • Jan Egil Afset
  • Bjørn Olav Åsvold
  • Erik Solligård
  • Jan Kristian DamåsEmail author



As iron is essential for both immune function and microbial growth, alterations in iron status could influence the risk of infections. We assessed the associations of iron status with risk of bloodstream infections (BSIs) and BSI mortality.


We measured serum iron, transferrin saturation (Tsat) and total iron-binding capacity (TIBC) in 61,852 participants in the population-based HUNT2 study (1995–97). Incident BSIs (1995–2011) were identified through linkage with the Mid-Norway Sepsis Register, which includes prospectively registered information on BSI from local and regional hospitals. We assessed the risk of a first-time BSI and BSI mortality with the iron indices using Cox proportional hazards regression analysis.


During a median follow-up of 14.8 years, 1738 individuals experienced at least one episode of BSI, and 370 died within 30 days after a BSI. In age- and sex-adjusted analyses, BSI risk was increased among participants with indices of iron deficiency, serum iron ≤ 2.5th percentile (HR 1.72, 95% CI 1.34–2.21), Tsat ≤ 2.5th percentile (HR 1.48, 95% CI 1.12–1.96) or TIBC ≥ 97.5th percentile (HR 1.46, 95% CI 1.06–2.01). The associations remained similar after adjusting for comorbidities and exclusion of BSI related to cancer, rheumatic illnesses and inflammatory bowel disease. BSI mortality showed similar associations.


Indices of severe iron deficiency are associated with an increased risk of a future BSI.


Bacteraemia Sepsis Iron Epidemiology Population based 



The Nord-Trøndelag Health Study (the HUNT study) is a collaboration of the HUNT research center (Faculty of Medicine, NTNU), Nord-Trøndelag County Council, Central Norway Health Authority and the Norwegian Institute of Public Health. We sincerely thank the microbiology departments of Levanger, Namsos and St. Olavs hospitals for providing microbial data and the Department for Research at Nord-Trøndelag Hospital Trust for assistance with data linkage.


This work was supported by a grant from The Liaison Committee for education, research and innovation in Central Norway.

Compliance with ethical standards

Conflicts of interest

Nothing to declare.

Supplementary material

134_2018_5320_MOESM1_ESM.doc (114 kb)
Supplementary material 1 (DOC 114 kb)


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature and ESICM 2018

Authors and Affiliations

  1. 1.Department of Circulation and Medical ImagingNorwegian University of Science and Technology (NTNU)TrondheimNorway
  2. 2.Centre of Molecular Inflammation Research, Norwegian University of Science and Technology (NTNU)TrondheimNorway
  3. 3.Department of Clinical and Molecular MedicineNorwegian University of Science and Technology (NTNU)TrondheimNorway
  4. 4.Department of Medical GeneticsNorwegian University of Science and Technology (NTNU)TrondheimNorway
  5. 5.Department of Public Health and NursingNorwegian University of Science and Technology (NTNU)TrondheimNorway
  6. 6.Mid-Norway Sepsis Research CenterNorwegian University of Science and Technology (NTNU)TrondheimNorway
  7. 7.K.G. Jebsen Center for Genetic EpidemiologyNorwegian University of Science and Technology (NTNU)TrondheimNorway
  8. 8.Clinic of Anaesthesia and Intensive CareSt. Olavs HospitalTrondheimNorway
  9. 9.Department of EndocrinologySt. Olavs HospitalTrondheimNorway
  10. 10.Department of Infectious DiseasesSt. Olavs HospitalTrondheimNorway
  11. 11.Department of Medicine, Levanger HospitalNord-Trøndelag Hospital TrustLevangerNorway
  12. 12.Department of Chronic Disease EpidemiologyYale School of Public HealthNew HavenUSA

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