Head injury and mortality in the homeless

Exploring the Role of Rehabilitation Medicine within an Inclusion Health Context: Examining a Population at Risk from Homelessness and Brain Injury in Edinburgh

People experiencing homelessness are at risk from a number of comorbidities, including traumatic brain injury, mental health disorders, and various infections. Little is known about the rehabilitation needs of this population. This study took advantage of unique access to a specialist access GP practice for people experiencing homelessness and a local inclusion health initiative to explore the five-year period prevalence of these conditions in a population of people experiencing homelessness through electronic case record searches and to identify barriers and facilitators to healthcare provision for this population in the context of an interdisciplinary and multispecialist inclusion health team through semi-structured interviews with staff working in primary and secondary care who interact with this population. The five-year period prevalence of TBI, infections, and mental health disorders was 9.5%, 4%, and 22.8%, respectively. Of those who had suffered a brain injury, only three had accessed rehabilitation services. Themes from thematic analysis of interviews included the impact of psychological trauma, under-recognition of the needs of people experiencing homelessness, resource scarcity, and the need for collaborative and adaptive approaches. The combination of quantitative and qualitative data suggests a potential role for rehabilitation medicine in inclusion health initiatives.

An Understated Comorbidity: The Impact of Homelessness on Traumatic Brain Injury

Traumatic brain injury (TBI), a neurovascular injury caused by external force, is a common diagnosis among veterans and those experiencing homelessness (HL). There is a significant overlap in the veteran and homeless population, possibly accounting for the two to seven times greater incidence of TBI among those experiencing HL than the general population. Despite these statistics, individuals experiencing HL are often underdiagnosed and ineffectively treated for TBI. We introduced a novel model of HL. Over 5 weeks, adult Sprague-Dawley rats were randomly assigned to one of the following conditions: TBI only, HL only, TBI + HL, or control (n = 9 per group). To emulate HL, animals (2 animals per cage) were exposed to soiled beddings for 5 weeks. Subsequently, animals were introduced to TBI by using the moderate controlled cortical impact model, then underwent 4 consecutive days of behavioral testing (beam walk (BW), elevated body swing test (EBST), forelimb akinesia (FA), paw grasp (PG), Rotorod, and elevated T-maze). Nissl staining was performed to determine the peri-impact cell survival and the integrity of corpus callosum area. Motor function was significantly impaired by TBI, regardless of housing (beam walk or BW 85.0%, forelimb akinesia or FA 104.7%, and paw grasp or PG 100% greater deficit compared to control). Deficits were worsened by HL in TBI rats (BW 93.3%, FA 40.5%, and PG 50% greater deficit). Two-way ANOVA revealed BW (F(4, 160) = 31.69, p < 0.0001), FA (F(4, 160) = 13.71, p < 0.0001), PG (F(4, 160) = 3.873, p = 0.005), Rotorod (F(4, 160), p = 1.116), and EBST (F(4, 160) = 6.929, p < 0.0001) showed significant differences between groups. The Rotorod and EBST tests showed TBI-induced functional deficits when analyzed by day, but these deficits were not exacerbated by HL. TBI only and TBI + HL rats exhibited typical cortical impact damage (F(3,95) = 51.75, p < 0.0001) and peri-impact cell loss compared to control group (F(3,238) = 47.34, p < 0.0001). Most notably, TBI + HL rats showed significant alterations in WM area measured via the corpus callosum (F(3, 95) = 3.764, p = 0.0133). Worsened behavioral outcomes displayed by TBI + HL rats compared to TBI alone suggest HL contributes to TBI functional deficits. While an intact white matter, such as the corpus callosum, may lessen the consequent functional deficits associated with TBI by enhancing hemispheric communications, there are likely alternative cellular and molecular pathways mitigating TBI-associated inflammatory or oxidative stress responses. Here, we showed that the environmental condition of the patient, i.e., HL, participates in white matter integrity and behavioral outcomes, suggesting its key role in the disease diagnosis to aptly treat TBI patients.

Association between traumatic brain injury and mental health care utilization: evidence from the Canadian Community Health Survey

BACKGROUND

Mental health disorders are a common sequelae of traumatic brain injury (TBI) and are associated with worse health outcomes including increased mental health care utilization. The objective of this study was to determine the association between TBI and use of mental health services in a population-based sample.

METHODS

Using data from a national Canadian survey, this study evaluated the association between TBI and mental health care utilization, while adjusting for confounding variables. A log-Poisson regression model was used to estimate unadjusted and adjusted prevalence ratios (PR) and 95% confidence intervals (CI).

RESULTS

The study sample included 158,287 TBI patients and 25,339,913 non-injured individuals. Compared with those were not injured, TBI patients reported higher proportions of chronic mental health conditions (27% vs. 12%, p < 0.001) and heavy drinking (33% vs. 24%, p = 0.005). The adjusted prevalence of mental health care utilization was 60% higher in patients with TBI than those who were not injured (PR = 1.60, 95%; CI 1.05-2.43).

CONCLUSIONS

This study suggests that chronic mental health conditions and heavy drinking are more common in individuals with TBI. The prevalence of mental health care utilization is 60% higher in TBI patients compared with those who are not injured after adjusting for sociodemographic factors, mental health conditions, and heavy drinking. Future longitudinal research is required to examine the temporality and direction of the association between TBI and the use of mental health services.

The Impact of COVID-19 on Access to Resources among Individuals Experiencing Homelessness and Traumatic Brain Injury

The rates of traumatic brain injury (TBI) are higher among individuals experiencing homelessness compared with the general population. Individuals experiencing homelessness and a TBI may experience barriers to care. COVID-19 may have further impacted access to basic resources, such as food, shelter, and transportation for individuals experiencing homelessness. This study aimed to answer the following research question: What is the impact of COVID-19 on access to resources among individuals experiencing homelessness and TBI? A cross-sectional study design and purposive sampling were utilized to interview 38 English-speaking adults experiencing homelessness and who had sustained a TBI (ages 21–73) in one Colorado city. Qualitative questions related to the impact of COVID-19 were asked and qualitative analysis was used to analyze the responses. Three primary themes emerged regarding the types of resources that were restricted by COVID-19: basic/biological needs, financial needs, and a lack of connection. COVID-19 has shown the social work field the need for continued innovation and better practice standards for individuals who are not housed. For those living with a reported TBI history and experiencing homelessness, COVID-19 made it difficult to access basic services for survival.

Cognitive Dysfunction, Brain Volumes, and Traumatic Brain Injury in Homeless Persons

Although homeless persons experience traumatic brain injury (TBI) frequently, little is known about the structural and functional brain changes in this group. We aimed to describe brain volume changes and related cognitive/motor deficits in homeless persons with or without TBI versus controls. Participants underwent T1-weighted magnetic resonance imaging (MRI), neuropsychological (NP) tests (the Grooved Pegboard Test [GPT]/Finger Tapping Test [FTT]), alcohol/drug use screens (the Alcohol Use Disorders Identification Test [AUDIT]/Drug Abuse Screening Test [DAST]), and questionnaires (the Brain Injury Screening Questionnaire [BISQ]/General Information Questionnaire [GIQ]) to determine TBI. Normalized volumes of brain substructures from MRI were derived from FreeSurfer. Comparisons were tested by Mann-Whitney U and Kruskal-Wallis rank sum tests. Leave-one-out cross-validation using random forest classifier was applied to determine the ability of predicting TBI. Diagnostic ability of this classifier was assessed using area under the receiver operating characteristic curve (AUC). Fifty-one participants—25 homeless persons (9 with TBI) and 26 controls—were included. The homeless group had higher AUDIT scores and smaller thalamus and brainstem volumes (p < 0.001) than controls. Within homeless participants, the TBI group had reduced normalized volumes of nucleus accumbens, thalamus, ventral diencephalon, and brainstem compared with the non-TBI group (p < 0.001). Homeless participants took more time on the GPT compared with controls using both hands (p < 0.0001); but the observed effects were more pronounced in the homeless group with TBI in the non-dominant hand. Homeless persons with TBI had fewer dominant hand finger taps than controls (p = 0.0096), and homeless participants with (p = 0.0148) or without TBI (p = 0.0093) tapped less than controls with their non-dominant hand. In all participants, TBI was predicted with an AUC of 0.95 (95% confidence interval [CI]: 0.89-1.00) by the classifier modeled on MRI, NP tests, and screening data combined. The MRI-data-based classifier was the best predictor of TBI within the homeless group (AUC: 0.76, 95% CI: 0.53-0.99). Normalized volumes of specific brain substructures were important indicators of TBI in homeless participants and they are important indicators of TBI in the state of homelessness itself. They may improve predictive ability of NP and screening tests in determining these outcomes.

Effect of Housing First on violence-related traumatic brain injury in adults with experiences of homelessness and mental illness: findings from the At Home/Chez Soi randomised trial, Toronto site

OBJECTIVES

People experiencing homelessness have a high prevalence and incidence of traumatic brain injury (TBI) due to violence. Little is known about the effectiveness of interventions to reduce TBI in this population. This study assessed the effect of Housing First (HF) on violence-related TBI in adults with experiences of homelessness and mental illness.

DESIGN

Pragmatic randomised trial.

PARTICIPANTS

381 participants in the Toronto site of the At Home/Chez randomised trial.

INTERVENTION

HF participants were provided with scattered-site housing using rent supplements and supports from assertive community treatment or intensive case management teams (n=218, 57.2%). Control participants had access to treatment as usual (TAU) in the community (n=163, 42.8%).

MAIN OUTCOME MEASURES

Primary outcomes were an incident physical violence-related TBI event and the number of physical violence-related TBI events during the follow-up period (January 2014 to March 2017). Interval-censored survival time regression and zero-inflated negative binomial regression were used to assess the effect of HF on primary outcomes.

RESULTS

Among study participants, 9.2% (n=35) had an incident physical violence-related TBI event, and the mean physical violence-related TBI events was 0.16 (SD ±0.6). Compared with TAU participants, HF participants did not have a significantly lower risk of an incident violence-related TBI event (adjusted HR : 0.58 (95% CI, 0.29 to 1.14)), but they had a significantly lower number of physical violence-related TBI events (unadjusted incidence rate ratio (IRR): 0.22 (95% CI, 0.06 to 0.78); adjusted IRR: 0.15 (95% CI, 0.05 to 0.48)).

CONCLUSION

HF may be a useful intervention to reduce the burden of TBI due to physical violence among homeless individuals with mental illness.

TRIAL REGISTRATION NUMBER

ISRCTN42520374.

Language ability and adult homelessness

BACKGROUND

People experiencing homelessness are at increased risk of neurological disorder due to multiple factors such as substance abuse, infection, and higher rates of serious mental illness and traumatic brain injury. This could affect cognitive and language skills. Indeed, past research has suggested that certain language-related skills tend to be lower in people experiencing homelessness. However, that research has compared homeless samples with age-matched normative samples and not with samples of people from similar socio-economic backgrounds. Therefore, it is unclear whether homelessness is even a relevant factor, or if adults who are homeless tend to have appropriate linguistic skills relative to their social and educational background.

AIMS

To compare the language skills of a group of adults with histories of homelessness with an education-matched control group. It was hypothesized that participants with histories of homelessness would have worse language performance than their matched controls.

METHODS & PROCEDURES

A quasi-experimental design was employed involving 17 adults with histories of homelessness, mainly rough sleeping, in the city of Quito in Ecuador, and a sample of 16 adults who had never been homeless. All were assessed with measures of head injury, substance dependence, affective disorder and language skills. A paired-sample analysis was performed on homeless and control participants matched for educational background, used as an index of socio-economic background.

OUTCOMES & RESULTS

The mean years of formal education was low in both the homeless sample (mean = 5.82 years) and the control sample (mean = 6.75 years). There were no differences between the groups for any demographic or clinical factors, nor for a measure of expected or 'premorbid' ability based on single-word reading, nor for current non-verbal cognitive functioning. In contrast, the homeless group scored significantly worse than the control group on measures of auditory comprehension and oral expression.

CONCLUSIONS & IMPLICATIONS

Adults with histories of homelessness may have worse language skills than would be expected based on their educational backgrounds and non-verbal cognitive abilities. It is possible that some of this lower language ability is pathological, in the form of either a developmental language disorder or an acquired impairment. As such, some adults who are homeless may benefit from therapy directed at clinical language disorders.

Trauma in adults experiencing homelessness

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.

The inter-relationship between acquired brain injury, substance use and homelessness; the impact of adverse childhood experiences: an interpretative phenomenological analysis study

PURPOSE

Acquired Brain Injuries, caused by a range of illnesses and injuries, can lead to long-term difficulties for individuals; mental health problems, cognitive and executive impairment and psychosocial problems including relationship breakdown, substance abuse and potentially homelessness. The study aimed to seek and gain a more definitive understanding of the inter-relationship of Acquired Brain Injury, substance abuse and homelessness by identifying key themes associated with the inter-relationship between these variables.

MATERIALS AND METHODS

The study recruited eight participants through homeless organisations and treatment centres. Participants were screened for suitability (Brain Injury Screening Index; Drug Abuse Screening Tool; Alcohol Use Disorders Identification Test and then participated in recorded semi-structured interviews, transcribed and analysed using Interpretative Phenomenological Analysis.

RESULTS

The study identified five master themes: Adverse Childhood Experiences and Trauma; Mental Health; Cognitive Decline and Executive Function; Services; Relationships.

CONCLUSION

Healthcare professionals need to engage with children, their families, and adults, who have been exposed to adverse childhood experiences and should employ routine screening tools for brain injury to ensure their presence is factored into developing appropriate models of intervention.IMPLICATIONS FOR REHABILITATIONNeed person-centred approaches to intervention for those with acquired brain injury who are homeless and have substance abuse issues.Need to screen for the presence of acquired brain injury when engaging with individuals who are homeless or have substance abuse.Need screening of acquired brain injury and adverse childhood experiences to improve access to services post-brain injury.

Traumatic brain injury in homeless and marginally housed individuals: a systematic review and meta-analysis

BACKGROUND

Homelessness is a global public health concern, and traumatic brain injury (TBI) could represent an underappreciated factor in the health trajectories of homeless and marginally housed individuals. We aimed to evaluate the lifetime prevalence of TBI in this population, and to summarise findings on TBI incidence and the association between TBI and health-related or functioning-related outcomes.

METHODS

For this systematic review and meta-analysis, we searched without date restrictions for original research studies in English that reported data on the prevalence or incidence of TBI, or the association between TBI and one or more health-related or function-related outcome measures. Studies were included if they had a group or clearly identifiable subgroup of individuals who were homeless, marginally housed, or seeking services for homeless people. With use of random-effects models, we calculated pooled estimates of the lifetime prevalence of any severity of TBI and the lifetime prevalence of moderate or severe TBI. We used meta-regression and subgroup analysis to evaluate potential moderators of prevalence estimates and the leave-one-out method for sensitivity analyses. We then summarised findings from all studies that evaluated TBI incidence and the association between TBI and health-related or functioning-related outcomes. All statistical analyses were done using R version 3.5.1. The study is registered with PROSPERO, number CRD42019119678.

FINDINGS

Of 463 potentially eligible studies identified by the search, 38 studies were included in the systematic review and 22 studies were included in the meta-analysis. The lifetime prevalence of any severity of TBI in homeless and marginally housed individuals (18 studies, n=9702 individuals) was 53·1% (95% CI 46·4-59·7; I²=97%) and the lifetime prevalence of moderate or severe TBI (nine studies, n=5787) was 22·5% (13·5-35·0; I²=99%). The method used to ascertain TBI history, the age of the sample, and the sample size significantly moderated estimated lifetime prevalence of any severity of TBI. TBI was consistently associated with poorer self-reported physical and mental health, higher suicidality and suicide risk, memory concerns, and increased health service use and criminal justice system involvement.

INTERPRETATION

The lifetime prevalence of TBI is high among homeless and marginally housed individuals, and a history of TBI is associated with poorer health and general functioning. Health-care providers and public health officials should have an increased awareness of the burden of TBI in this population. Prospective and longitudinal studies are needed to better understand how the health of this population is affected by TBI.

FUNDING

Canadian Institutes of Health Research.

Utility of the Brain Injury Screening Index in Identifying Female Prisoners With a Traumatic Brain Injury and Associated Cognitive Impairment

There is a high prevalence of traumatic brain injury (TBI) in prisoners, but screening tools for identifying TBI in female prisoners are not readily available. Using a cross-sectional design, the psychometric properties of the Brain Injury Screening Index (BISI) were investigated in a closed United Kingdom female prison. Purposive sampling comprised 56 females. Assessment included clinical interview, the BISI, self-report measures of mood, and a battery of measures of cognitive functioning. Seven of the 10 clinical indicators on the BISI met test-retest reliability criteria. Two of the three BISI summary variables demonstrated correlations with questionnaires in the hypothesized directions; however, only two BISI variables were associated with cognitive functioning. Findings support further investigation into the validity and reliability of the BISI with a larger sample.

Cognitive impairment and homelessness: A scoping review

This paper reports the findings of a scoping review designed to identify research which has explored the relationship between cognitive impairment and homelessness. A systematic search of databases for articles published between 2007 and 2017 was conducted using keywords relating to cognitive impairments and homelessness. Sources were expanded using manual searches of citations and grey literature. Forty studies represented in 45 papers were selected for review using predefined inclusion criteria. Sources were subject to quality appraisal and data were extracted in line with review questions. Prevalence studies were over-represented in the review, while qualitative data were lacking. Aetiology of impairments was delineated by acquired and developmental causes. A variety of measures were employed by studies which were not validated in homeless populations. Studies did not give sufficient consideration to co-occurring disorders and overlapping symptoms between aetiologies. Because of these factors, it was difficult to conclude that all studies had accurately measured what they set out to; however, the evidence suggested that cognitive impairment was disproportionately over-represented in homeless populations. Cognitive impairment was found to be both a risk factor to and perpetuator of homelessness. Risk factors for homelessness were similar to those of the general population, though exaggerated by sequelae of certain cognitive impairments. The results of this review suggest that more attention needs to be paid to the underlying socioeconomic disadvantages, persons with cognitive impairments face which may lead to homelessness. Further research should prioritise the voice of homeless persons with cognitive impairments, to better understand both causes of homelessness and effective methods of rehabilitation.

The development of the Brain Injury Screening Index (BISI): A self-report measure

The aim of this study was to investigate the psychometric properties and screening accuracy of the Brain Injury Screening Index (BISI), a self-report questionnaire designed to identify a history of acquired brain injury. The study was conducted in a closed male prison in the UK. The purposive sample comprised 55 male prisoners who arrived at the establishment during the study. A repeated measures design was used, where the Brain Injury Screening Index (BISI) was administered on three occasions. Inter-rater reliability was poor to moderate, but test retest reliability was moderate to good. Medical records were not available for all participants, but the limited number obtained resulted in a sensitivity of .38 to .71 and specificity of .47 to .70 across the three screening administrations of the BISI. The limitations of the present findings are discussed in the context of the use of the tool in custodial environments. It is argued that these results suggest that, when used as recommended, the BISI has acceptable reliability and validity as an initial screen for identifying individuals who should receive support and a comprehensive neuropsychological assessment, and it merits further investigation and development.

The high burden of traumatic brain injury and comorbidities amongst homeless adults with mental illness

OBJECTIVE

characterize the prevalence of self-reported head injury with loss of consciousness (LOC) and associated demographic, clinical and service use factors in a sample of homeless adults with mental illness.

METHOD

Participants in the At Home/Chez Soi study were interviewed at the time of study enrollment regarding their history of head injuries, mental and physical health diagnoses and justice system and healthcare interactions. Sociodemographic and clinical data were also collected.

RESULTS

Over half of the 2088 study respondents (52.6%, n = 1098) reported a history of head injury with a LOC, which was associated with several demographic, clinical and service use variables in this population. With respect to specific mental health conditions, a history of head injury with LOC was associated with higher odds of current depression (OR = 2.18, CI: 1.83-2.60), manic episode or hypomanic episode (OR = 1.91, CI: 1.45-2.50), PTSD (OR = 2.98, CI: 2.44-3.65), panic disorder (OR = 2.37, CI:1.91-2.93), mood disorder (OR = 1.78, CI: 1.40-2.26) and alcohol (OR = 2.09, CI: 1.75-2.49) and drug (OR = 1.73, CI: 1.46-2.06) misuse disorders, but reduced odds of having diagnosis of a psychotic disorder (OR = 0.63, CI: 0.53-0.76). A history of head injury with LOC was also associated with increased use of variety of services, including family medicine (OR = 1.33, CI: 1.12-1.59), criminal justice system (OR = 1.50, CI: 1.25-1.80) and the emergency department (OR = 1.03, CI: 1.01-1.05).

CONCLUSIONS

Amongst homeless adults with mental illness having a history of head injuries with LOC was independently associated with various adverse outcomes. These individuals constitute a high-risk group who may benefit from specialized services.

Chronic impact of traumatic brain injury on outcome and quality of life: a narrative review

Traditionally seen as a sudden, brutal event with short-term impairment, traumatic brain injury (TBI) may cause persistent, sometimes life-long, consequences. While mortality after TBI has been reduced, a high proportion of severe TBI survivors require prolonged rehabilitation and may suffer long-term physical, cognitive, and psychological disorders. Additionally, chronic consequences have been identified not only after severe TBI but also in a proportion of cases previously classified as moderate or mild. This burden affects the daily life of survivors and their families; it also has relevant social and economic costs.

Outcome evaluation is difficult for several reasons: co-existing extra-cranial injuries (spinal cord damage, for instance) may affect independence and quality of life outside the pure TBI effects; scales may not capture subtle, but important, changes; co-operation from patients may be impossible in the most severe cases. Several instruments have been developed for capturing specific aspects, from generic health status to specific cognitive functions. Even simple instruments, however, have demonstrated variable inter-rater agreement.

The possible links between structural traumatic brain damage and functional impairment have been explored both experimentally and in the clinical setting with advanced neuro-imaging techniques. We briefly report on some fundamental findings, which may also offer potential targets for future therapies.

Better understanding of damage mechanisms and new approaches to neuroprotection-restoration may offer better outcomes for the millions of survivors of TBI.