Homelessness as a predictor of mortality: an 11-year register-based cohort study

  • Sandra Feodor NilssonEmail author
  • Thomas Munk Laursen
  • Carsten Hjorthøj
  • Merete Nordentoft
Original Paper



The purpose of this study was to examine the association between homelessness and psychiatric disorders, including substance use disorders, on one hand, and cause-specific and all-cause mortality on the other in a high-income country.


A historical nationwide register-based cohort study of the Danish population from 15 years of age between 2000 and 2011 was conducted. The association between homelessness, psychiatric disorders, and mortality was analysed by Poisson Regression adjusting for important confounders. Standardised mortality ratios (SMRs) were calculated for people with a history of homelessness compared with the general population using direct age-standardisation.


During 51,892,324 person-years of observation, 656,448 died. People with at least one homeless shelter contact accounted for 173,592 person-years with 4345 deaths. The excess mortality in the population experiencing homelessness compared with the general population was reduced by 50% after adjusting for psychiatric diagnoses, including substance use disorders (mortality rate ratio (MRR) for men 3.30, 95% CI 3.18–3.41; women 4.41, 95% CI 4.14–4.71). Full adjustment including physical comorbidity and socioeconomic factors in a sub-cohort aged 15–29 years resulted in an MRR of 3.94 (95% CI 3.10–5.02) compared with the general population. The excess mortality associated with homelessness differed according to psychiatric diagnosis, sex, and cause of death.


A mental health or a substance use disorder combined with homelessness considerably increases the risk of death. However, homelessness is also independently associated with high mortality. Differences in the association between homelessness and mortality in men and women suggest the need for sex-tailored interventions.


Homeless persons Mortality Mental disorders Substance abuse Epidemiology 



Supported by the University of Copenhagen, Department of Clinical Medicine.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Supplementary material

127_2017_1456_MOESM1_ESM.docx (201 kb)
Adjusted cumulative incidence function (CIF) of all-cause (A–B) and cause-specific mortality (C–F) among people using homeless shelters with and without a psychiatric diagnosis previous to first homeless shelter contact by age at first homeless shelter contact (DOCX 200 KB)
127_2017_1456_MOESM2_ESM.docx (14 kb)
Supplementary material 2 (DOCX 14 KB)


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Copyright information

© Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  • Sandra Feodor Nilsson
    • 1
    • 2
    Email author
  • Thomas Munk Laursen
    • 3
    • 4
  • Carsten Hjorthøj
    • 2
    • 4
  • Merete Nordentoft
    • 1
    • 2
    • 4
  1. 1.Department of Clinical Medicine, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
  2. 2.Copenhagen University Hospital, Mental Health Centre CopenhagenMental Health Services in the Capital Region of DenmarkHellerupDenmark
  3. 3.The National Centre for Register-Based ResearchAarhus UniversityAarhusDenmark
  4. 4.iPSYCH-The LundbeckFoundation Initiative for Integrated Psychiatric ResearchAarhusDenmark

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