Abstract. Objectives: To characterize the homeless adult population of an urban emergency department (ED) and study the medical, psychiatric, and social factors that contribute to homelessness. Methods: A prospective, case-control survey of all homeless adult patients presenting to an urban, tertiary care ED and a random set of non-homeless controls over an eightweek period during summer 1999. Research assistants administered a 50-item questionnaire and were trained in assessing dentition and triceps skin-fold thickness. Inclusion criteria: all homeless adults who consented to participate. Homelessness was defined as being present for any person not residing at a private address, group home, or drug treatment program. Randomly selected controls were concurrently enrolled with a 3:1 homeless:control rate. Exclusion criteria: critically ill, injured, or incapacitated patients, or patients <21 years of age. Univariate analysis with appropriate statistical tests was used. The Mantel-Haenszel test was used to adjust for population differences. Results: Two hundred fifty-two homeless subjects and 88 controls were enrolled. Data are presented for homeless vs control patients, and all p-values were <0.01. Odds ratios (ORs) with 95% confidence intervals (95% CIs) are given where appropriate: mean age (ϮSD) = 42 Ϯ 10 vs 48 Ϯ 13; male gender 95% vs 54% (OR = 17; 95% CI = 8 to 37); history of (hx) tuberculosis 49% vs 15% (OR = 2.5; 95% CI = 1.2 to 3); hx HIV infection 35% vs 13% (OR = 3.8; 95% CI = 1.8 to 8); hx penetrating trauma 62% vs 16% (OR = 8.62; 95% CI = 4.4 to 17.1); hx depression 70% vs 15% (OR = 13.4; 95% CI = 6.7 to 27); hx schizophrenia 27% vs 7% (OR = 5.1; 95% CI = 2.0 to 14); hx alcoholism 81% vs 15% (OR = 24; 95% CI = 12 to 49); significant tooth loss (>3) 43% vs 18% (OR = 3.3; 95% CI = 1.8 to 6.4); percentage of body fat 16.5% vs 19.7%; hx social isolation (no weekly social contacts) 81% vs 11% (OR = 33.3; 95% CI = 14 to 100); mean number of ED visits/year 6.0 vs 1.6. Conclusions: In the study population homelessness was associated with a history of significantly higher rates of infectious disease, ethanol and substance use, psychiatric illness, social isolation, and rates of ED utilization.

In three independent cohorts, 3-hour bundle compliance was associated with improved survival and cost savings.