Characterizing traumatic brain injury in unsheltered homelessness: prevalence of TBI and cognitive sequelae in individuals utilizing street medicine.

Abstract

Context: People experiencing homelessness are at a disproportionately greater risk for developing traumatic brain injury (TBI) than the general population. There has been minimal research to evaluate the prevalence of TBI or the long-term cognitive impacts of TBI among the population experiencing homelessness within the United States. There is minimal literature that examines individuals who are living unsheltered, especially regarding TBI.

Objectives: This study aimed to assess primarily whether those experiencing unsheltered homelessness had a higher prevalence of TBI than those in shelter. Furthermore, we examined the differences in the prevalence of repeated TBIs, TBI by age of respondent, loss of consciousness (LOC), and cognitive symptoms in people experiencing homelessness across three housing strata (sheltered, low-barrier sheltered, and unsheltered) within a small midwestern city.

Methods: Participants were recruited utilizing a convenience sampling of patients who utilized street medicine healthcare services. The study enrolled 102 patients during the interval of October 2022 through March 2024 from three housing strata (sheltered, low-barrier sheltered, and unsheltered) in Lansing, Michigan. We employed the Ohio State TBI Identification Method, abbreviated for ease of use. Results were analyzed for associations between TBI and health conditions utilizing chi-squared tests and a single difference-of-proportions test.

Results: Seventy-five of 102 (73.5 %) of participants reported at least one TBI, with 48 % experiencing their first TBI more than 20 years ago. There was a significant difference in TBI prevalence across housing strata. Ninety percent (90 %) of unsheltered survey respondents reported at least one previous TBI, with 50 % reporting three or more previous TBIs. These rates exceeded those of respondents in shelter (58 % prevalence, 21 % 3+ TBIs) and low-barrier shelter (65.1 % prevalence, 26 % 3+ TBIs), all of which exceeded the reported TBI prevalence for the general population (21.7 %). TBI prevalence did not vary significantly by age. LOC following TBI among participants significantly exceeded that of the general population (48 vs. 12 %). The prevalence of severe TBI was significantly greater than the general population for low-barrier shelter (16 vs. 2.6 %) and unsheltered respondents (23 %), but not for sheltered participants. Many respondents (62.6 %) developed cognitive symptoms as a result of TBI, although no statistical difference emerged between the groups. Cognitive sequalae were most common among those with three or more TBIs.

Conclusions: Taken together, these results suggest that the likelihood of TBI and the associated risks present a greater threat to those experiencing homelessness. There is a propensity to most strongly affect those living unsheltered.