Homelessness as an independent risk factor for mortality: results from a retrospective cohort study

Abstract

Background: Homelessness is associated with increased risks of mortality but it has not previously been possible to distinguish whether this is typical of other socio-economically deprived populations, the result of a higher prevalence of morbidity or an independent risk of homelessness itself. The aim of this study was to describe mortality among a cohort of homeless adults and adjust for the effects of morbidity and socio-economic deprivation.

Methods: Retrospective 5-year study of two fixed cohorts, homeless adults and an age- and sex-matched random sample of the local non-homeless population in Greater Glasgow National Health Service Board area for comparison.

Results: Over 5 years of observation, 1.7% (209/12 451) of the general population and 7.2% (457/6323) of the homeless cohort died. The hazard ratio of all-cause mortality in homeless compared with non-homeless cohorts was 4.4 (95% CI: 3.8-5.2). After adjustment for age, sex and previous hospitalization, homelessness was associated with an all-cause mortality hazard ratio of 1.6 (95% CI: 1.3-1.9). Homelessness had differential effects on cause-specific mortality. Among patients who had been hospitalized for drug-related conditions, the homeless cohort experienced a 7-fold increase in risk of death from drugs compared with the general population.

Conclusions: Homelessness is an independent risk factor for deaths from specific causes. Preventive programmes might be most effectively targeted at the homeless with these conditions.