Abstract
OBJECTIVES: Cancer is a leading cause of death in unhoused adults. We sought to examine the association between housing status, stage at diagnosis and all-cause survival following cancer diagnosis at a public hospital. DESIGN: Retrospective cohort study examining new cancer diagnoses between 1 July 2011 and 30 June 2021. SETTING: A public hospital in San Francisco. EXPOSURE: Housing status (housed, formerly unhoused, unhoused) was ascertained via a county-wide integrated dataset that tracks both observed and reported homelessness. METHODS: We reported univariate analyses to investigate differences in demographic and clinical characteristics by housing group. We then constructed Kaplan-Meier curves stratified by housing group to examine unadjusted all-cause mortality. Finally, we used multivariable Cox proportional hazards models to compare the hazard rate of mortality for each housing status group, adjusting for demographic and clinical factors. RESULTS: Our cohort included 5123 patients with new cancer diagnoses, with 4062 (79%) in housed patients, 623 (12%) in formerly unhoused patients and 438 (9%) in unhoused patients. Unhoused and formerly unhoused patients were more commonly diagnosed with stage 4 disease (28% and 27% of the time, respectively, vs 22% of housed patients). After adjusting for demographic and clinical characteristics, unhoused patients with stage 0-3 disease had a 50% increased hazard of death (adjusted HR (aHR) 1.5, 95% CI 1.1 to 1.9; p<0.004) as did formerly unhoused patients (aHR 1.5, 95% CI 1.2 to 1.9; p=0.001) compared with housed individuals 3 months after diagnosis. CONCLUSIONS: Unhoused and formerly unhoused patients diagnosed with non-metastatic cancer had substantially increased hazards of death compared with housed patients cared for in a public hospital setting. Current or former lack of housing could contribute to poor outcomes following cancer diagnoses via multiple mechanisms.