Traumatic brain injury among men in an urban homeless shelter: observational study of rates and mechanisms of injury.

BACKGROUND Little empiric research has investigated the interrelationship between homelessness and traumatic brain injury. The objectives of this study were to determine the rate, mechanisms and associated outcomes of traumatic brain injury among men in an urban homeless shelter. METHODS We recruited participants from an urban men's shelter in Toronto, Ontario. Researchers administered the Brain Injury Screening Questionnaire, a semistructured interview screening tool for brain injury. Demographic information and detailed histories of brain injuries were obtained. Participants with positive and negative screening results were compared, and the rates and mechanisms of injury were analyzed by age group. RESULTS A total of 111 men (mean age 54.2 ± standard deviation 11.5 yr; range 27-81 yr) participated. Nearly half (50 [45%]) of the respondents had a positive screening result for traumatic brain injury. Of these, 73% (35/48) reported experiencing their first injury before adulthood (< 18 yr), and 87% (40/46) reported a first injury before the onset of homelessness. Among those with a positive screening result, 33 (66%) reported sustaining at least one traumatic brain injury by assault, 22 (44%) by sports or another recreational activity, 21 (42%) by motor vehicle collision and 21 (42%) by a fall. A positive screening result was significantly associated with a lifetime history of arrest or mental illness and a parental history of substance abuse. INTERPRETATION Multiple mechanisms contributed to high rates of traumatic brain injury within a sample of homeless men. Assault was the most common mechanism, with sports and recreation, motor vehicle collisions and falls also being reported frequently by the participants. Injury commonly predated the onset of homelessness, with most participants experiencing their first injury in childhood. Additional research is needed to understand the complex interactions among homelessness, traumatic brain injury, mental illness and substance use.