The prevalence of mental disorders among homeless people in high-income countries: An updated systematic review and meta-regression analysis

BackgroundHomelessness continues to be a pressing public health concern in many countries, and mental disorders in homeless persons contribute to their high rates of morbidity and mortality. Many primary studies have estimated prevalence rates for mental disorders in homeless individuals. We conducted a systematic review and meta-analysis of studies on the prevalence of any mental disorder and major psychiatric diagnoses in clearly defined homeless populations in any high-income country.Methods and findingsWe systematically searched for observational studies that estimated prevalence rates of mental disorders in samples of homeless individuals, using Medline, Embase, PsycInfo, and Google Scholar. We updated a previous systematic review and meta-analysis conducted in 2007, and searched until 1 April 2021. Studies were included if they sampled exclusively homeless persons, diagnosed mental disorders by standardized criteria using validated methods, provided point or up to 12-month prevalence rates, and were conducted in high-income countries. We identified 39 publications with a total of 8,049 participants. Study quality was assessed using the JBI critical appraisal tool for prevalence studies and a risk of bias tool. Random effects meta-analyses of prevalence rates were conducted, and heterogeneity was assessed by meta-regression analyses. The mean prevalence of any current mental disorder was estimated at 76.2% (95% CI 64.0% to 86.6%). The most common diagnostic categories were alcohol use disorders, at 36.7% (95% CI 27.7% to 46.2%), and drug use disorders, at 21.7% (95% CI 13.1% to 31.7%), followed by schizophrenia spectrum disorders (12.4% [95% CI 9.5% to 15.7%]) and major depression (12.6% [95% CI 8.0% to 18.2%]). We found substantial heterogeneity in prevalence rates between studies, which was partially explained by sampling method, study location, and the sex distribution of participants. Limitations included lack of information on certain subpopulations (e.g., women and immigrants) and unmet healthcare needs.ConclusionsPublic health and policy interventions to improve the health of homeless persons should consider the pattern and extent of psychiatric morbidity. Our findings suggest that the burden of psychiatric morbidity in homeless persons is substantial, and should lead to regular reviews of how healthcare services assess, treat, and follow up homeless people. The high burden of substance use disorders and schizophrenia spectrum disorders need particular attention in service development. This systematic review and meta-analysis has been registered with PROSPERO (CRD42018085216).Trial registrationPROSPERO CRD42018085216.

In an updated systematic review and meta analysis, Stefan Gutwinski, Stefanie Schreiter, and colleagues examine the prevalence of mental disorders among individuals who are homeless in high income countries.     

Substance Use and Access to Health Care and Addiction Treatment among Homeless and Vulnerably Housed Persons in Three Canadian Cities

Introduction

We examined the prevalence of substance use disorders among homeless and vulnerably housed persons in three Canadian cities and its association with unmet health care needs and access to addiction treatment using baseline data from the Health and Housing in Transition Study.

Methods

In 2009, 1191 homeless and vulnerably housed persons were recruited in Vancouver, Toronto, and Ottawa, Canada. Interviewer administered questionnaires collected data on socio-demographics, housing history, chronic health conditions, mental health diagnoses, problematic drug use (DAST-10≥6), problematic alcohol use (AUDIT≥20), unmet physical and mental health care needs, addiction treatment in the past 12 months. Three multiple logistic regression models were fit to examine the independent association of substance use with unmet physical health care need, unmet mental health care need, and addiction treatment.

Results

Substance use was highly prevalent, with over half (53%) screening positive for the DAST-10 and 38% screening positive for the AUDIT. Problematic drug use was 29%, problematic alcohol use was lower at 16% and 7% had both problematic drug and alcohol use. In multiple regression models for unmet need, we found that problematic drug use was independently associated with unmet physical (adjusted odds ratio [AOR] 1.95; 95% confidence interval [CI] 1.43–2.64) and unmet mental (AOR 3.06; 95% CI 2.17–4.30) health care needs. Problematic alcohol use was not associated with unmet health care needs. Among those with problematic substance use, problematic drug use was associated with a greater likelihood of accessing addiction treatment compared to those with problematic alcohol use alone (AOR 2.32; 95% CI 1.18–4.54).

Conclusions

Problematic drug use among homeless and vulnerably housed individuals was associated with having unmet health care needs and accessing addiction treatment. Strategies to provide comprehensive health services including addiction treatment should be developed and integrated within community supported models of care.     

Predictors of Frequent Emergency Room Visits among a Homeless Population

Background

Homelessness, HIV, and substance use are interwoven problems. Furthermore, homeless individuals are frequent users of emergency services. The main purpose of this study was to identify risk factors for frequent emergency room (ER) visits and to examine the effects of housing status and HIV serostatus on ER utilization. The second purpose was to identify risk factors for frequent ER visits in patients with a history of illicit drug use.

Methods

A retrospective analysis was performed on 412 patients enrolled in a Boston-based health care for the homeless program (HCH). This study population was selected as a 2:1 HIV seronegative versus HIV seropositive match based on age, sex, and housing status. A subgroup analysis was performed on 287 patients with history of illicit drug use. Chart data were analyzed to compare demographics, health characteristics, and health service utilization. Results were stratified by housing status. Logistic models using generalized estimating equations were used to predict frequent ER visits.

Results

In homeless patients, hepatitis C was the only predictor of frequent ER visits (OR 4.49, p<0.01). HIV seropositivity was not predictive of frequent ER visits. In patients with history of illicit drug use, mental health (OR 2.53, 95% CI 1.07–5.95) and hepatitis C (OR 2.85, 95% CI 1.37–5.93) were predictors of frequent ER use. HIV seropositivity did not predict ER use (OR 0.45, 95% CI 0.21 – 0.97).

Conclusions

In a HCH population, hepatitis C predicted frequent ER visits in homeless patients. HIV seropositivity did not predict frequent ER visits, likely because HIV seropositive HCH patients are engaged in care. In patients with history of illicit drug use, hepatitis C and mental health disorders predicted frequent ER visits. Supportive housing for patients with mental health disorders and hepatitis C may help prevent unnecessary ER visits in this population.     

Experience of Primary Care among Homeless Individuals with Mental Health Conditions

The delivery of primary care to homeless individuals with mental health conditions presents unique challenges. To inform healthcare improvement, we studied predictors of favorable primary care experience among homeless persons with mental health conditions treated at sites that varied in degree of homeless-specific service tailoring. This was a multi-site, survey-based comparison of primary care experiences at three mainstream primary care clinics of the Veterans Administration (VA), one homeless-tailored VA clinic, and one tailored non-VA healthcare program. Persons who accessed primary care service two or more times from July 2008 through June 2010 (N = 366) were randomly sampled. Predictor variables included patient and organization characteristics suggested by the patient perception model developed by Sofaer and Firminger (2005), with an emphasis on mental health. The primary care experience was assessed with the Primary Care Quality-Homeless (PCQ-H) questionnaire, a validated survey instrument. Multiple regression identified predictors of positive experiences (i.e. higher PCQ-H total score). Significant predictors of a positive experience included a site offering tailored service design, perceived choice among providers, and currently domiciled status. There was an interaction effect between site and severe psychiatric symptoms. For persons with severe psychiatric symptoms, a homeless-tailored service design was significantly associated with a more favorable primary care experience. For persons without severe psychiatric symptoms, this difference was not significant. This study supports the importance of tailored healthcare delivery designed for homeless persons’ needs, with such services potentially holding special relevance for persons with mental health conditions. To improve patient experience among the homeless, organizations may want to deliver services that are tailored to homelessness and offer a choice of providers.     

Social, structural and behavioral determinants of overall health status in a cohort of homeless and unstably housed HIV-infected men

Background

Previous studies indicate multiple influences on the overall health of HIV-infected persons; however, few assess and rank longitudinal changes in social and structural barriers that are disproportionately found in impoverished populations. We empirically ranked factors that longitudinally impact the overall health status of HIV-infected homeless and unstably housed men.

Methods and Findings

Between 2002 and 2008, a cohort of 288 HIV+ homeless and unstably housed men was recruited and followed over time. The population was 60% non-Caucasian and the median age was 41 years; 67% of study participants reported recent drug use and 20% reported recent homelessness. At baseline, the median CD4 cell count was 349 cells/µl and 18% of eligible persons (CD4<350) took antiretroviral therapy (ART). Marginal structural models were used to estimate the population-level effects of behavioral, social, and structural factors on overall physical and mental health status (measured by the SF-36), and targeted variable importance (tVIM) was used to empirically rank factors by their influence. After adjusting for confounding, and in order of their influence, the three factors with the strongest negative effects on physical health were unmet subsistence needs, Caucasian race, and no reported source of instrumental support. The three factors with the strongest negative effects on mental health were unmet subsistence needs, not having a close friend/confidant, and drug use. ART adherence >90% ranked 5th for its positive influence on mental health, and viral load ranked 4th for its negative influence on physical health.

Conclusions

The inability to meet food, hygiene, and housing needs was the most powerful predictor of poor physical and mental health among homeless and unstably housed HIV-infected men in an urban setting. Impoverished persons will not fully benefit from progress in HIV medicine until these barriers are overcome, a situation that is likely to continue fueling the US HIV epidemic.     

Developments for a growing Japanese patient population: facilitating new technologies for future health care

Lung cancer, COPD and cardiovascular diseases are highlighted as some of the most common disease that cause mortality, and for that reason are the most active areas for drug development. This perspective paper overviews the urgent need to develop a health care system for a rapidly growing patient population in Japan, including forthcoming demands on clinical care, expecting outcomes, and economics. There is an increasing requirement to build on the strengths of the current health care system, thereby delivering urgent solutions for the future. There is also a declaration from the Ministry of Health, Labour and Welfare (MHLW), to develop new biomarker diagnostics, which is intended for patient stratification, aiding in diagnostic phenotype selection for responders to drug treatment of Japanese patients. This perspective was written by the panel in order to introduce novel technologies and diagnostic capabilities with successful implementation. The next generation of personalized drugs for targeted and stratified patient treatment will soon be available in major disease areas such as, lifestyle-related cancers, especially lung cancers with the highest mortality including a predisposing disorder chronic obstructive pulmonary disease, cardiovascular disease, and other diseases. Mass spectrometric technologies can provide the "phenotypic fingerprint" required for the concept of Personalized Medicine. Mass spectrometry-driven target biomarker diagnoses in combination with high resolution computed tomography can provide a critical pathway initiative facilitated by a fully integrated e-Health infrastructure system. We strongly recommend integrating validated biomarkers based on clinical proteomics, medical imaging with clinical care supported by e-Health model to support personalized treatment paradigms to reduce mortality and healthcare costs of chronic and co-morbid diseases in the elderly population of Japan.     

The Prevalence of Mental Disorders among the Homeless in Western Countries: Systematic Review and Meta-Regression Analysis

Background

There are well over a million homeless people in Western Europe and North America, but reliable estimates of the prevalence of major mental disorders among this population are lacking. We undertook a systematic review of surveys of such disorders in homeless people.

Methods and Findings

We searched for surveys of the prevalence of psychotic illness, major depression, alcohol and drug dependence, and personality disorder that were based on interviews of samples of unselected homeless people. We searched bibliographic indexes, scanned reference lists, and corresponded with authors. We explored potential sources of any observed heterogeneity in the estimates by meta-regression analysis, including geographical region, sample size, and diagnostic method. Twenty-nine eligible surveys provided estimates obtained from 5,684 homeless individuals from seven countries. Substantial heterogeneity was observed in prevalence estimates for mental disorders among the studies (all Cochran''s χ² significant at p < 0.001 and all I ² > 85%). The most common mental disorders were alcohol dependence, which ranged from 8.1% to 58.5%, and drug dependence, which ranged from 4.5% to 54.2%. For psychotic illness, the prevalence ranged from 2.8% to 42.3%, with similar findings for major depression. The prevalence of alcohol dependence was found to have increased over recent decades.

Conclusions

Homeless people in Western countries are substantially more likely to have alcohol and drug dependence than the age-matched general population in those countries, and the prevalences of psychotic illnesses and personality disorders are higher. Models of psychiatric and social care that can best meet these mental health needs requires further investigation.     

Prevalence of Mental Illness among Homeless People in Hong Kong

MetholodogyThis study examined the prevalence and correlates of mental illness in homeless people in Hong Kong and explored the barriers preventing their access to health care. Ninety-seven Cantonese-speaking Chinese who were homeless during the study period were selected at random from the records of the three organisations serving the homeless population. The response rate was 69%. Seventeen subjects could not give valid consent due to their poor mental state, so their responses were excluded from the data analysis. A psychiatrist administered the Structured Clinical Interview for DSM-IV Axis-I disorders (SCID-I) and the Mini -Mental State Examination. Consensus diagnoses for subjects who could not complete the SCID-I were established by three independent psychiatrists.FindingsThe point prevalence of mental illness was 56%. Seventy-one percent of the subjects had a lifetime history of mental illness, 30% had a mood disorder, 25% had an alcohol use disorder, 25% had a substance use disorder, 10% had a psychotic disorder, 10% had an anxiety disorder and 6% had dementia. Forty-one percent of the subjects with mental illness had undergone a previous psychiatric assessment. Only 13% of the subjects with mental illness were receiving psychiatric care at the time of interview. The prevalence of psychotic disorders, dementia and the rate of under treatment are hugely underestimated, as a significant proportion (18%) of the subjects initially selected were too ill to give consent to join the study.ConclusionThe low treatment rate and the presence of this severely ill and unreached group of homeless people reflect the fact that the current mode of service delivery is failing to support the most severely ill homeless individuals.     

Innovative HIV/AIDS program launched in Ottawa.

Collaboration among 31 social and health care agencies and the provincial government has resulted in an innovative program for Ottawa-area patients with HIV infection or AIDS. The target group is the homeless and people with "unstable" housing who live in the city''s downtown core, a group at high risk of contracting HIV. The education of family practitioners will be an important part of the program.     

Tort reform and the obstetric access crisis. The case of the WAMI states.

The states of Washington, Alaska, Montana, and Idaho (WAMI) have all had declines in the proportion of physicians offering obstetric services during the past few years, a decline precipitated by rising medical malpractice premiums. One response to the problem of rising liability premiums has been the passage of extensive tort reform legislation. We present the results of recent studies of physicians'' obstetric practices in the WAMI states and summarize the major changes in tort legislation and regulation that have occurred in these states. Most general and family physicians in the WAMI region no longer provide obstetric care; by contrast, more than 80% of the obstetrician-gynecologists in the WAMI states are still practicing obstetrics. Despite the fact that only a minority of family physicians are still active in obstetrics, most rural family physicians in all four states still deliver babies. Most physicians in all four states limit the amount of care they provide to those covered by Medicaid, which suggests that significant barriers to care exist for medically indigent persons. All four states have adopted significant tort reforms. Despite these changes in the legal environment, the cost of malpractice premiums and concerns over the likelihood of being sued continue to limit the number of physicians willing to provide obstetric care. Although it cannot be inferred from these data that tort reform has decreased the rate at which physicians give up obstetric practice, the evidence is compatible with such a conclusion.     

The Rural Health Program of Southern Monterey County

The Rural Health Project of Southern Monterey County is attempting to demonstrate that a private group of physicians with the collaboration of the County Medical Society can responsibly and efficiently conduct a program of providing comprehensive medical care to indigent patients.Within the purposes of P.L. 89-749, the Rural Health Project is experimenting with a new way of organizing indigent health care and at the same time is providing the basis for comprehensive health planning at the local level.     

Relationship between subjective assessment of oral health and medical expenses in community-dwelling elderly persons

doi: 10.1111/j.1741‐2358.2011.00459.x
Relationship between subjective assessment of oral health and medical expenses in community‐dwelling elderly persons Objectives: The increasing medical expenses of elderly persons in Japan’s rapidly ageing society have become a major concern. It is therefore important to elucidate the factors associated with such escalation. Here, we focused on the relationship between subjective self‐assessment of oral health, as an index of general health, and medical expenses (excluding dental repair) under the hypothesis that oral health contributes to general medical expenses. Several studies have shown that oral health status is correlated with general health status among elderly persons. We speculated that oral health status might show a relation with medical costs among elderly persons. However, few studies have investigated this relationship to date. Materials and Methods: Participants were 259 elderly subjects (range: 65–84 years; 120 men, 139 women) residing independently. Subjective assessment of oral health was evaluated by their responses (‘Good’, ‘Not good’ and ‘Not at all good’) on a survey questionnaire. The correlation between subjective assessment of oral health and medical expenditure was analysed using Spearman’s rank method, the Mann–Whitney U‐test and the Kruskal–Wallis test. Medical expenses were used as the dependent variable in multinomial logistic regression analysis with background and intraoral factors as independent variables. Results: A slight yet statistically significant correlation was observed between subjective assessment of oral health and outpatient treatment fees. Conclusion: The findings revealed that subjective assessment of oral health is significantly and independently related to the medical expenses of community‐dwelling elderly persons after adjusting for social background, living environment and physical factors.     

Health conditions of bus drivers in a 6 year follow up study

The bus drivers of a public bus company, working in a fast rotating 4 shift system from 05.00 to 24.30, were examined in 1993 (230 persons) and 1999 (266 persons). The comparison between the two years showed no significant differences for all the parameters evaluated by the Standard Shiftwork Index and medical examination. In both surveys work organisation was considered "efficient-fairly good" by most workers, who were mostly satisfied with their job. Work load was rated significantly higher for "afternoon" and "morning" shifts, during which most accidents at work and "in itinere" occurred. Night sleep was reduced by 3 hours on "early" shift and about 2 hours on "morning" shifts. The most prevalent health troubles dealt with low back pain, gastritis, headache and haemorrhoids. Neuroticism was the trait more correlated with poorer health conditions, whereas shiftwork exposure appeared as a significant predictor of risk of critical Effort/Reward Imbalance and minor psychological disorders. Both extrinsic and intrinsic efforts significantly increased with age, but not reward. The comparison of the same cohort of 108 persons examined both in 1993 and in 1999 showed a significant increase of low back pain, gastrointestinal troubles, haemorrhoids and lipids disorders.     

Access and Use of Medical Care among Obese Persons

The prevalence of obesity and severe obesity is growing rapidly, along with obesity‐related comorbidities and mortality. Given the increased health risks associated with obesity, it is vital that obese persons have adequate access to, and make consistent use of, medical care services. Assuming obese persons have access to medical care that is comparable to non‐obese persons, one would expect to observe greater use of medical services among obese persons. In this article we briefly review empirical evidence of the access to and use of medical care among obese persons. Although certain subgroups that tend to have disproportionately high prevalences of obesity (i.e., low socioeconomic status, minority groups) have reduced access to care, no studies have specifically examined whether or not obese persons have the same access to health care as do their lean counterparts. With respect to use of health care services, however, obesity has been consistently linked with greater rates of utilization and increased health care expenditures. Both the increased use and cost appear to be largely a function of treating obesity‐associated comorbidities such as diabetes and hypertension. We conclude that, although it is clear that obesity is associated with both greater use and cost of medical care, the relationship between obesity and access to medical care has not been determined.     

Factors and Models Associated with the amount of Hospital Care Services as Demanded by Hospitalized Patients: A Systematic Review

Background

Hospitals are constantly being challenged to provide high-quality care despite ageing populations, diminishing resources, and budgetary restraints. While the costs of care depend on the patients'' needs, it is not clear which patient characteristics are associated with the demand for care and inherent costs. The aim of this study was to ascertain which patient-related characteristics or models can predict the need for medical and nursing care in general hospital settings.

Methods

We systematically searched MEDLINE, Embase, Business Source Premier and CINAHL. Pre-defined eligibility criteria were used to detect studies that explored patient characteristics and health status parameters associated to the use of hospital care services for hospitalized patients. Two reviewers independently assessed study relevance, quality with the STROBE instrument, and performed data analysis.

Results

From 2,168 potentially relevant articles, 17 met our eligibility criteria. These showed a large variety of factors associated with the use of hospital care services; models were found in only three studies. Age, gender, medical and nursing diagnoses, severity of illness, patient acuity, comorbidity, and complications were the characteristics found the most. Patient acuity and medical and nursing diagnoses were the most influencing characteristics. Models including medical or nursing diagnoses and patient acuity explain the variance in the use of hospital care services for at least 56.2%, and up to 78.7% when organizational factors were added.

Conclusions

A larger variety of factors were found to be associated with the use of hospital care services. Models that explain the extent to which hospital care services are used should contain patient characteristics, including patient acuity, medical or nursing diagnoses, and organizational and staffing characteristics, e.g., hospital size, organization of care, and the size and skill mix of staff. This would enable healthcare managers at different levels to evaluate hospital care services and organize or reorganize patient care.     

基层医疗卫生机构的基本医疗服务范围研究 ——基于常见病、多发病的视角

目的 基于常见病、多发病的视角界定基层医疗卫生机构的基本医疗服务范围。方法 以广东省A市为例,根据该市基本医疗保险参保人的微观数据,统计分析了该市的常见病、多发病,并对该市128个医疗机构进行问卷调查。结果 分别确定了社区卫生服务中心104个病种、乡镇卫生院101个病种、社区卫生服务站38个病种和村卫生室34个病种作为四类基层医疗卫生机构的基本医疗服务范围。结论 应依据四类基层医疗卫生机构的基本医疗服务范围从诊疗项目、药品目录、基层首诊制等方面进行政策调整与完善。     

New perspectives for the elucidation of genetic disorders

For almost 15 years, genome research has focused on the search for major risk factors in common diseases, with disappointing results. Only recently, whole-genome association studies have begun to deliver because of the introduction of high-density single-nucleotide-polymorphism arrays and massive enlargement of cohort sizes, but most of the risk factors detected account for only a small proportion of the total genetic risk, and their diagnostic value is negligible. There is reason to believe that the complexity of many "multifactorial" disorders is primarily due to genetic heterogeneity, with defects of different genes causing the same disease. Moreover, de novo copy-number variation has been identified as a major cause of mental retardation and other complex disorders, suggesting that new mutations are an important, previously overlooked factor in the etiology of complex diseases. These observations support the notion that research into the previously neglected monogenic disorders should become a priority of genome research. Because of the introduction of novel high-throughput, low-cost sequencing methods, sequencing and genotyping will soon converge, with far-reaching implications for the elucidation of genetic disease and health care.     

A national survey of laboratory animal workers concerning occupational risks for zoonotic diseases

In this cross-sectional survey of laboratory animal workers in the United States, 23 of 1367 persons reported 28 cases of infection with zoonotic agents from research animals at their workplace during the past 5 years, with six persons indicating that their infections were medically confirmed. Based on these data, the annualized incidence rate for work-related transmission of zoonotic agents from laboratory animals was 45 cases per 10,000 worker-years at risk (95% confidence interval, 30 to 65 cases), approximating the rate for nonfatal occupational illnesses in the agricultural production-livestock industry and for those employed in the health services during 2002. Logistic regression analysis found various characteristics of persons and their employers that were significantly associated with the likelihood of having been medically evaluated for exposure to a zoonotic agent from laboratory animals. Most (95.595% +/- 1.1%) persons working with laboratory animals or their tissues indicated that they knew whom to talk to at their institution for medical evaluation and care should they be concerned about the possibility of an occupationally acquired zoonotic disease in future. However, occupational illnesses and exposures among laboratory animal workers was underreported, as 10 of the 28 (36%) alleged zoonotic disease cases were not communicated to the employee's supervisor. Lack of concern about the potential significance to their health and the perception of punitive consequences to the employee were some of the reasons cited for underreporting, an issue which must be vigorously addressed in the interests of continuing progress toward zoonotic disease prevention in this field.     

Utilisation by homeless people of acute hospital services in London.

OBJECTIVES--To estimate the numbers and distribution of homeless people in London; to quantify the utilisation of acute inpatient services by homeless people in two health authorities; and to predict the total numbers of admissions in homeless people in district health authorities across London. DESIGN--Data were collected from various sources on the distribution of homeless people across London boroughs. All unplanned acute inpatient admissions during November 1990 to relevant hospitals were identified. SETTING--Bloomsbury and Paddington and North Kensington, two former inner London district health authorities. SUBJECTS--Homeless people in London residing in bed and breakfast and private sector leased accommodation, residing in hostels, and of no fixed abode. MAIN OUTCOME MEASURES--Number and cost of acute unplanned admissions in homeless people in two health authorities in November 1990; predicted number of such admissions each year in district health authorities in London. RESULTS--There were at least 60,000 homeless people in London in March 1990. The majority were housed in temporary accommodation (55,412). There were at least 3295 hostel dwellers and 651 people sleeping rough. Homeless people accounted for 105 (8%) of the 1256 acute unbooked admissions in residents of Bloomsbury and Paddington and North Kensington health authorities in November 1990. Considerable variations in the pattern of acute unplanned admissions in homeless people were observed in the two districts with respect to housing status and specialty of admission. The total number of acute unplanned admissions in homeless people across London each year was estimated at 7598, ranging from 38 in Bexley to 1515 in Parkside. CONCLUSIONS--The results have fundamental implications for resource allocation across London. Allocation must take better account of the heterogeneity, uneven distribution, and extra health needs of homeless people.