Trauma in adults experiencing homelessness

Abstract

Background: Homeless individuals suffer a greater burden of health problems than the general population. This study aimed to describe the epidemiology of physical trauma among homeless patients presenting to an urban major trauma center and to ascertain any differences in the nature, injury severity and outcomes among homeless compared to domiciled patients.

Methods: A retrospective matched cohort study that included adults who met inclusion criteria for The Alfred Hospital Trauma Registry between 01 July 2010 and 31 March 2017 was conducted. Primary homelessness was identified using the International Statistical Classification of Diseases, 10th Revision Coding Z59.0 and/or 'No fixed abode' address data. Homeless and domiciled patients were matched at a 1:2 ratio on age, sex, month and year of injury. The primary outcome variable was the Injury Severity Score (ISS). Secondary outcomes were hospital length of stay (LOS), mortality, emergency department (ED) disposition, hospital disposition, discharge processes and trauma registry recidivism.

Results: Of 25,920 cases in the trauma registry, 147 (0.6%) were identified as homeless, comprising 131 unique homeless individuals who were matched with 262 domiciled patients. The median (Inter-Quartile Range) ISS among homeless patients was 5(2-10), compared to 9(4-17) for domiciled patients (p < 0.001). Homeless patients had significantly lower odds of sustaining an injury with ISS>12 (OR 0.5, 95% CI: 0.3-0.8, p = 0.001). Homeless patients were treated more often than domiciled patients for assault (32.1% vs 9.5%), intentional self-harm (10.7% vs 2.7%), and penetrating injury (16.0% vs 6.5%). Homeless patients had higher rates of psychiatry admissions (9.2% vs 0.8%), positive blood alcohol concentration (30.5% vs 13.7%), and higher odds of discharging against medical advice (DAMA)(OR 2.0, 95% CI: 1.1-3.6 p = 0.02). There were no differences in LOS (p = 0.51), mortality (p = 0.19), ED disposition (p = 0.64) or trauma registry recidivism (p = 0.09).

Conclusion: Among injured patients who presented at an urban trauma center, homelessness was associated with higher odds of assault, intentional self-harm, penetrating injury, psychiatry admissions, DAMA but lower ISS than domiciled patients. Variable definitions of homelessness and lack of standardized documentation in the medical record should be addressed to ensure these vulnerable patients are identified and linked with peripheral services.

Keywords: Discharged against medical advice; Homelessness; Injury; Injury severity score; Mortality; Patient discharge; Psychiatry.