Hospital Readmissions in a Community-based Sample of Homeless Adults: a Matched-cohort Study.

Background: Hospital readmission rates are a widely used quality indicator that may be elevated in disadvantaged populations.

Objective: The objective of this study was to compare the hospital readmission rate among individuals experiencing homelessness with that of a low-income matched control group, and to identify risk factors associated with readmission within the group experiencing homelessness.

Design: We conducted a 1:1 matched cohort study comparing 30-day hospital readmission rates between homeless patients and low-income controls matched on age, sex and primary reason for admission. Multivariate analyses using generalized estimating equations were used to assess risk factors associated with 30-day readmission in the homeless cohort.

Participants: This study examined a cohort of 1,165 homeless adults recruited at homeless shelters and meal programs in Toronto, Ontario, between 6 December 2004 and 20 December 2005.

Main Measures: The primary outcome was the occurrence of an unplanned medical or surgical readmission within 30 days of discharge from hospital.

Key Results: Between 6 December 2004 and 31 March 2009, homeless participants (N = 203) had 478 hospitalizations and a 30-day readmission rate of 22.2 %, compared to 300 hospitalizations and a readmission rate of 7.0 % among matched controls (OR = 3.79, 95 % CI 1.93-7.39). In the homeless cohort, having a primary care physician (OR = 2.65, 95 % CI 1.05-6.73) and leaving against medical advice (OR = 1.96, 95 % CI 0.99-3.86) were associated with an increased risk of 30-day readmission.

Conclusions: Homeless patients had nearly four times the odds of being readmitted within 30-days as compared to low-income controls matched on age, sex and primary reason for admission to hospital. Further research is needed to evaluate interventions to reduce readmissions among this patient population.