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Abstract

Objective

The health of people living in marginal housing is not well characterized, particularly from the perspective of multimorbid illness. The authors investigated this population in a community sample.

Method

A prospective community sample (N=293) of adults living in single-room occupancy hotels was followed for a median of 23.7 months. Assessment included psychiatric and neurological evaluation, multimodal MRI, and viral testing.

Results

Previous homelessness was described in 66.6% of participants. Fifteen deaths occurred during 552 person-years of follow-up. The standardized mortality ratio was 4.83 (95% CI=2.91–8.01). Substance dependence was ubiquitous (95.2%), with 61.7% injection drug use. Psychosis was the most common mental illness (47.4%). A neurological disorder was present in 45.8% of participants, with definite MRI findings in 28.0%. HIV serology was positive in 18.4% of participants, and hepatitis C virus serology in 70.3%. The median number of multimorbid illnesses (from a list of 12) was three. Burden of multimorbidity was significantly correlated with lower role functioning score. Comorbid addiction or physical illness significantly decreased the likelihood of treatment for psychosis but not the likelihood of treatment for opioid dependence or HIV disease. Participants who died during follow-up appeared to have profiles of multimorbidity similar to those of the overall sample.

Conclusions

This marginally housed cohort had greater than expected mortality and high levels of multimorbidity with adverse associations with role function and likelihood of treatment for psychosis. These findings may guide the development of effective health care delivery in the setting of marginal housing.

Enclaves of marginal or substandard urban housing with low-income tenants are associated with substance dependence, mental illness, and infectious diseases (1, 2). This is the case in both resource-rich and resource-limited settings (2). In the Downtown Eastside neighborhood of Vancouver, British Columbia, single-room occupancy hotels have low barriers to tenancy and are often the only alternative to homelessness. In response to an epidemic of overdose deaths in this neighborhood, a supervised injecting facility was established (3). Specific initiatives were also deployed to facilitate access to highly active antiretroviral therapy (4). These initiatives limited overdose deaths (3) and decreased HIV-/AIDS-related morbidity and mortality as well as new HIV diagnoses (4). However, knowledge concerning the general health of people living in marginal housing is poor (5). Street homelessness, or living in shelters, is associated with high mortality and is linked to psychiatric disorders, including substance abuse (6, 7). Living in marginal housing may be associated with mortality similar to that associated with homelessness (8).

Increasing emphasis is being placed on the role of multimorbidity in determining health outcomes (9). In aging populations, physical illness may predispose to psychiatric disorders (10). For the relatively younger residents of single-room occupancy hotels, physical illness may be a consequence of substance dependence and mental illness (11). The implications of injected opioid dependence for infectious disease are relatively well defined (12). Less is known about risks related to stimulant drugs, particularly crack cocaine and methamphetamine, which are often used nonparenterally (1315). Neurological disorders in the homeless include traumatic brain injury (TBI) (16) and cognitive impairment (17). The prevalence of other neurological disorders, such as seizures, movement disorders, and stroke, is unknown. The relationships between neurological illness, substance dependence, and mental illness are unclear, as are the implications for psychosocial function and the ability to access medical care. This information is important to inform efforts to control HIV and hepatitis C virus (HCV) through the implementation of “seek, test, treat, and retain” strategies (18, 19). To begin to establish an evidence base addressing these issues, we initiated a longitudinal cohort study of multimorbidity in residents of single-room occupancy hotels. We report the baseline findings and mortality for the initial 2-year phase of follow-up.

Method

Study Enrollment and Design

The study was carried out in Vancouver, British Columbia, with staggered recruitment from single-room occupancy hotels located in a low-income neighborhood and managed by a not-for-profit housing agency. In Canada, below-standard housing is defined as falling short in at least one of the following criteria: adequacy (not in need of repairs, according to residents), affordability (costs <30% of before-tax household income), or suitability (makeup of bedrooms and household). In many single-room occupancy hotels, the need for repairs is obvious even from casual observation. Rents generally range from 40% to 65% of the income provided by social service benefits. The single-room occupancy hotels typically comprise single rooms of 80 to 120 square feet (8–12 m2), with a sink and possibly a hotplate. Toilet and shower facilities, located at the end of hallways, are shared by 10 to 15 tenants. All single-room occupancy hotels housing study participants were over 75 years old and had evidence of bedbug, cockroach, and mouse infestation.

Following the baseline assessment (see Table 1 for instruments used [2041]), the study design included monthly follow-up for up to 5 years. Inclusion criteria were living in one of four single-room occupancy hotels and ability to communicate in English. Inability to provide informed consent was the sole exclusion criterion. Informed consent was obtained to communicate clinically significant findings to the participants’ physicians. Medical care was provided free of charge through the Canadian health system. Participants received a modest honorarium. The protocol was approved by the ethics board of the University of British Columbia.

TABLE 1. Baseline Assessment Measures for Tenants Living in Single-Room Occupancy Hotels
Variable and Assessment Measure
Sociodemographic data
Standard interview incorporates questions from the Canadian Community Health Survey (20). (Administered by a research assistant.)
Substance use
Initial interview records lifetime history of use, age of first exposure, and periods of heavy use for alcohol and illicit drugs. (Administered by a research assistant.)
Fagerström Test for Nicotine Dependence (21). (Administered by a research assistant.)
Maudsley Addiction Profile (22): assesses drug use, related mental and physical symptoms, and risk behaviors for the past 30 days. Includes a rating of frequency of thoughts of ending life, scored on a scale of 0 to 4, with 2 representing “sometimes.” (Administered by a research assistant.)
Time-Line Follow-Back (23): records alcohol and drug use (prescribed and illicit, types, amounts, and pattern) over the previous 4 weeks, as well as money spent on alcohol and illicit drugs. (Administered by a research assistant.)
Urine drug screen: detects amphetamines, methamphetamine, barbiturates, benzodiazepines, cocaine (crack), marijuana, methadone, 3,4-methylenedioxymethamphetamine (Ecstasy), opiates, and tricyclic antidepressants. (Administered by a research assistant.)
Mental illness
Mini-International Neuropsychiatric Interview (24, 25): a semistructured clinical interview used to collect information allowing a diagnosis of DSM-IV axis I disorders, validated in substance-using and general medical samples. (Administered by a research assistant.)
International Personality Disorder Examination, Screener (26): a screening instrument for DSM-IV personality disorders. (Administered by a research assistant.)
Positive and Negative Syndrome Scale (27): a 30-item scale rated after an interview and mental status examination by a psychiatrist, used to assess the severity of a range of symptoms of psychosis and general mental health. (Administered by a psychiatrist.)
Beck Depression Inventory (28): a self-report measure of depression, including an assessment of suicidal ideation, scored on a scale of 0 to 3, with 1 representing thoughts of killing self, without intent. (Administered by a research assistant.)
Trauma History Questionnaire (29): measures exposure to traumatic life events and records frequency and age of exposure. (Administered by a research assistant.)
Best Estimate Clinical Evaluation and Diagnosis (30): information obtained from all assessments and from hospital records is used to make DSM-IV diagnoses of substance dependence and mental illness. (Psychiatrist assessment.)
Cognitive functioning
Wechsler Test of Adult Reading (31): provides an index of premorbid intellectual ability. (Administered by a research assistant/neuropsychologist interpretation.)
Stroop color and word test (32): measures the ability of the individual to separate word and color naming stimuli; this requires sustained attention and inhibition of a dominant response set. (Administered by a research assistant/neuropsychologist interpretation.)
Intradimensional-extradimensional shift task from the Cambridge Neuropsychological Automated Test Battery (33): evaluates attentional shifting to attributes of a complex stimulus array. (Administered by a research assistant/neuropsychologist interpretation.)
Rapid Visual Information Processing Task from the Cambridge Neuropsychological Automated Test Battery (34): a test that requires monitoring and responding to specific digit sequences and inhibiting responses to distracters. (Administered by a research assistant/neuropsychologist interpretation.)
Hopkins Verbal Learning Test, Revised (35): a brief assessment of memory, which includes many of the elements also found in detailed tests, such as the California Verbal Learning Test. (Administered by a research assistant/neuropsychologist interpretation.)
Iowa gambling task (36): assesses decision making in response to differential incentive conditions, sensitive to orbitofrontal functioning, and used to evaluate decision making. (Administered by a research assistant/neuropsychologist interpretation.)
Neurological illness
Traumatic brain injury: inquiry into serious head or facial injury, the event causing the injury, the extent of the injury, duration of loss of consciousness, need for hospitalization, duration of symptoms of dizziness, blurred vision, and confusion or memory loss. (Administered by a research assistant/neuropsychologist interpretation.)
Extrapyramidal Symptom Rating Scale (37): rated after a movement disorders examination. (Administered by a psychiatrist or neurologist.)
Barnes Akathisia Rating Scale (38): rated after a movement disorders examination. (Administered by a psychiatrist or neurologist.)
Cambridge Neurological Inventory (39): a focused neurological examination for motor coordination and sensory integration soft signs, including anomia. (Administered by a psychiatrist or neurologist.)
Medical illness
Serology for HIV, hepatitis B virus, and hepatitis C virus, qualitative polymerase chain reaction for hepatitis C virus; blood samples were drawn for testing at the British Columbia Centre for Disease Control.
CBC and differential, platelet count, AST, ALT.
Psychosocial functioning
Role Functioning Scale (40): a rating of daily functioning in four domains (work productivity, independent living, and immediate and extended social network relationships; each rated on a scale of 1 to 7). Higher scores represent better function. (Administered by a research assistant.)
Social and Occupational Functioning Assessment Scale (41): rated on a scale of 0 to 100, with higher scores representing better functioning. (Administered by a research assistant.)
TABLE 1. Baseline Assessment Measures for Tenants Living in Single-Room Occupancy Hotels
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Assessment of Mortality

Mortality is the only outcome reported from follow-up. For participants who died, hospital records were obtained from the year before death; health care providers were interviewed; and coroner’s reports were requested.

Assessment of Substance Dependence

A lifetime review of substance exposure was obtained, and drug-dependence-related sections of the Mini-International Neuropsychiatric Interview were completed. A description, on a week-by-week basis, of all alcohol and prescription, licit, and illicit drugs used over the previous 4 weeks was recorded, as well as scores for the Maudsley Addiction Profile for the same period. A urine drug screen also was obtained.

Assessment and Diagnosis of Mental Illness

Records of hospitalization for mental illness were obtained, dating as far back as 50 years. The Mini-International Neuropsychiatric Interview was administered, and it was supplemented by a clinical interview and mental status examination carried out by a psychiatrist. All available clinical information (see Table 1) was used to make psychiatric and substance dependence diagnoses using procedures from the Best Estimate Clinical Evaluation and Diagnosis form (30), as previously used for genetic studies (42) and adapted in this study to DSM-IV criteria rather than DSM-III-R criteria. Previous reports of these diagnostic procedures indicated between-rater reliabilities of 0.53 to 0.91 for major mental disorders (43). The two diagnosticians in this study (F.V.R. and W.G.H.) used this diagnostic process independently for 98 participants. For the major mental illness categories reported, the kappa values were 0.77 for psychosis, 0.60 for mood disorders, and 0.61 for anxiety disorders. For substance dependence, the kappa values were 0.81 for alcohol, 0.74 for methamphetamine, 0.71 for cocaine, and 0.73 for opioids. Level of psychosocial functioning was rated using the Role Functioning Scale (40) and the Social and Occupational Functioning Assessment Scale in DSM-IV (41).

Assessment and Diagnosis of Physical Illness

Medical history was reviewed with a structured interview. Inquiry into neurological symptoms included history of seizures (most recent and treatment) and TBI, including duration of loss of consciousness, confusion or memory loss, dizziness, headache or blurred vision, and need for hospitalization. A screening neurological examination was carried out by a psychiatrist or a neurologist, and ratings were completed. Cognitive disorders were diagnosed on the basis of clinical findings from the history, the neurological examination, and neuropsychological testing, according to DSM-IV criteria.

An MRI scan was obtained using a Philips 3.0-T Achieva scanner (Philips Healthcare, Amsterdam). Sequences included a full-brain three-dimensional spoiled gradient echo, fluid attenuated inversion recovery, three-dimensional venous blood-oxygen-level-dependent imaging, and MR angiography. All MRI scans were reviewed by a neuroradiologist, and findings were reported according to standardized definitions (44).

Blood samples drawn for testing at the British Columbia Centre for Disease Control included serology for HIV, hepatitis B virus (HBV), and HCV, as well as qualitative polymerase chain reaction for HCV. A CBC and differential with platelet count was conducted, and AST and ALT levels were determined.

Statistical Analysis

The standardized mortality ratio was calculated (by H.W.). This was the ratio of the observed number of deaths to the number of deaths expected if the study cohort experienced the age- and sex-specific death rates seen in the 2009 Canadian general population. The Boice-Monson method was used to calculate the 95% confidence interval.

The likelihood-ratio chi-square test was used to compare the prevalence of seizures and of cognitive impairment in those with and without a history of TBI (this and subsequent analyses were conducted by W.G.H.). A similar approach was used to compare risk behavior in the past 30 days between participants who were infectious (with HIV, HCV, or HBV) and those who were not.

To examine the consequences of multimorbidity for psychosocial function, we selected 12 illnesses (psychosis; alcohol, stimulant, or opioid dependence; movement disorder; TBI; seizures; cognitive impairment; brain infarction; and active HIV, HCV, or HBV infection). Each participant was assigned a multimorbidity score representing the sum of illnesses present, with a range of 0–12. If an illness, such as stroke, was not assessed because of contraindications for MRI or serology for an illness was missing, that illness was scored as absent. Spearman correlation was performed between the multimorbidity score and the total score for the Role Functioning Scale, as well as the score for the Social and Occupational Functioning Assessment Scale.

To investigate the possible effects of multimorbidity on likelihood of treatment, we examined treatment history regarding psychosis (antipsychotic drug treatment prescribed), opioid dependence (methadone prescribed), and HIV (highly active antiretroviral therapy prescribed). In the group of participants with psychosis, we used the likelihood-ratio chi-square statistic to compare the use of antipsychotic drugs among participants with psychosis only with the use among participants with psychosis and comorbid opioid dependence or HIV. Similar comparisons were performed in the opioid-dependent group, using methadone treatment as the outcome, and in the HIV-infected group, using highly active antiretroviral therapy as the outcome.

Results

Participants

Participants were enrolled in a staggered fashion between November 13, 2008, and July 31, 2011. On a hotel-by-hotel basis, all tenants were approached to participate, and 293/406 (72.2%) agreed and met inclusion criteria. Table 2 summarizes participants’ demographic characteristics. At enrollment, most participants had lived in their current single-room occupancy hotel for over a year. Two-thirds had a history of homelessness. By the end of the period of observation, 150/292 (51.4%) participants were living in the same hotels as at enrollment. Most others were living nearby in different hotels, and only 15/292 (5.1%) had become homeless.

TABLE 2. Demographic Characteristics of Tenants Living in Single-Room Occupancy Hotels
Characteristic
NMedianInterquartile Range
Age (years)29344.137.1–50.9
Monthly income (Canadian dollars)286870610–1,100
Months in current hotel at baseline292162–52
Months since last homeless195388–93
Total NN%
Female2936823.2
Current marital status
 Married or common-law2935017.1
 Separated or divorced2936722.9
 Single29317660.1
Ethnicity
 White29317258.7
 Black29372.4
 Asian29382.7
 Aboriginal2938328.3
 Mixed/other293237.8
Education
 Did not complete high school29316857.3
 Completed high school29311338.6
 Completed a college or university program293124.1
Earned income in addition to benefits291237.6
Homeless in the past29319566.6
Jailed in the past2937124.2
TABLE 2. Demographic Characteristics of Tenants Living in Single-Room Occupancy Hotels
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Mortality

As a consequence of the staggered enrollment to allow completion of baseline assessments, participants had a variable period of follow-up or months at risk, ending January 31, 2012 (minimum for all participants, 6 months; 31/293 (11%) were lost to follow-up before the sixth monthly assessment). The median period of risk was 23.7 months, taken into account as part of the calculation of standardized mortality ratio. During 552 person-years of observation, 15/293 (5.1%) participants died. Coroner’s reports were obtained for the seven who died outside hospital settings. No deaths were attributed to suicide, 10 were a consequence of physical illness, and five were drug overdose-related (see Table S1 in the data supplement that accompanies the online edition of this article). The standardized mortality ratio was 4.83 (95% confidence interval=2.91–8.01) compared with age- and sex-matched Canadian population data.

Substance Dependence and Mental Illness

Substance dependence affected nearly all participants (Table 3). In the previous year, 179/290 (61.7%) participants had injected drugs, and 241/292 (82.5%) participants reported ever having injected. Mental illness affected the majority of participants, most commonly psychosis. Current suicidal ideation (defined as a score ≥1 on the suicidal ideation item of the Beck Depression Inventory [1=thoughts of suicide but would not carry it out] and a score ≥2 on the suicidal ideation item of the Maudsley Addiction Profile [2=thoughts of ending life sometimes]) was present in 28/288 (9.7%) participants. Only a minority (30/293 [10.2%]) had a history of long-term psychiatric hospitalization, with a greater number reporting hospitalization for mental illness in a general hospital (105/293 [35.8%]). Similar proportions suffered from schizophrenia or other chronic form of psychosis or from substance-induced psychosis (see Table S2 in the online data supplement).

TABLE 3. Prevalence of Multimorbid Illness Among Single-Room Occupancy Hotel Tenants
Clinical CharacteristicTotal NBaseline
Lifetime
N%N%
Substance dependence, any (nicotine excluded)a29327995.228798.0
Stimulant use (cocaine and/or methamphetamine)29324081.925787.7
Opioid use (heroin or other)29311539.217961.9
Alcohol dependence2935619.114047.8
Tobacco use (daily)28924083.026090.0
Mental illness, anyb29321874.425085.3
Psychotic illness, any29313947.417258.7
Mood disorder, any2938729.715552.9
Anxiety disorder, any2937023.59231.4
Neurological illness (active and/or current treatment)c27312545.8
Movement disorderd2695219.3
Brain infarction on MRI, any2322611.2
Aneurysm on MR angiography232208.6
Traumatic brain injury (definite)e2933110.6
Seizures in past year and/or current treatment292268.9
Clinical cognitive impairment (according to DSM-IV criteria)293196.5
Other neurological illnessf29341.4
Other MRI findingsg23273.0
Infection
 Anti-HIV positive2835218.4
 Anti-hepatitis C virus positive28319970.3
 Hepatitis C viremia (hepatitis C virus seropositive only)19014576.3
AST:platelet ratio index (hepatitis C virus seropositive only)h
 0–0.719113972.8
 >0.71915227.2
 >2191115.8
Hepatitis B virus surface antigen positive28331.1

a Additional details on the prevalence of individual substance dependence are presented in Table S2 in the online data supplement.

b Additional details on the prevalence of individual mental illnesses are presented in Table S2 in the data supplement.

c Additional details on the prevalence of individual neurological disorders are presented in Table S3 in the data supplement.

d Data indicate parkinsonism, dyskinesia, or akathisia symptoms representing a score of moderate or greater on the Extrapyramidal Symptom Rating Scale or the Barnes Akathisia Rating Scale.

e Data are for participants with evidence of previous traumatic brain injury (TBI) on MRI (N=19) or history of TBI (loss of consciousness ≥5 minutes or confusion ≥1 day) and persistent symptoms referable to TBI, including seizures or organic personality disorder (N=12).

f Data are for participants with myotonic dystrophy (N=1), multiple sclerosis (N=1), narcolepsy (N=1), or AIDS white-matter encephalopathy (N=1).

g Data are for participants with Chiari type 2 malformation (N=2), heterotopic gray matter (N=2), demyelination, (N=1), skull-base lesion (N=1), or AIDS white-matter encephalopathy (N=1).

h The ratio was calculated using the local laboratory upper limit of normal, which equaled 35; analysis was limited to those with anti-hepatitis C virus positive serology because the predictive value of the index is best evaluated in this population; values >0.7 are associated with hepatic fibrosis and those >2 with hepatic cirrhosis.

TABLE 3. Prevalence of Multimorbid Illness Among Single-Room Occupancy Hotel Tenants
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Neurological Illness and Viral Exposure

Movement disorders were the most common neurological finding and were often associated with exposure to stimulant or antipsychotic drugs or both (Table 3; see also Table S3 in the data supplement). Of those with a movement disorder, the frequencies of the most common syndromes were as follows: parkinsonism, N=11/52 (21.2%); dyskinesia, N=23/52 (44.2%); and akathisia, N=34/52 (65.4%).

Pathological findings on MRI were found in 65/232 (28.0%) participants; brain infarction was the most common finding. The prevalence rate was 13/143 (9.1%) for those 30–49 years old, 11/57 (19.3%) for those 50–59 years old, and 2/11 (18.2%) for those 60–67 years old. For those with brain infarction, rates of seizures, movement disorder, or clinically significant cognitive impairment did not differ significantly from those of participants with no brain infarction. Of the 20 aneurysms detected on MR angiography, all were 7 mm or less in size, and one each was located in the anterior or posterior communicating artery. A participant who died from a subarachnoid hemorrhage did not have an aneurysm detected on the earlier MRI.

A history of serious head or facial injury was endorsed by 186/292 (63.7%) participants; more narrowly defined TBI was less frequent (Table 3). Examples of MRI findings related to TBI are presented in Figure S1 in the online data supplement. Seizures were more common in those with definite TBI (N=15/31 [48.4%]) than in those without (N=11/262 [4.2%] p<0.001). Similarly, clinical diagnoses of cognitive impairment were more frequent among participants with definite TBI (N=10/31 [32.3%]) compared with those without (N=9/262 [3.4%] p<0.001).

Positive serology for HCV and for HIV was common. Nine new cases of HCV, two new carriers of HBV, and one new case of HIV were detected at study entry. The AST:platelet ratio index was above a threshold of 2.0, suggestive of hepatic cirrhosis, in 5.8% of participants (Table 3; see also Table S4 in the data supplement). Only 10 participants reported previous interferon-based treatment for HCV. In contrast, nearly all those with positive HIV serology had received antiretroviral therapy, with 42/47 (89.4%) of those with available data having virologic suppression in the past (see Table S5 in the data supplement). Behaviors known to increase the risk of viral transmission, including penetrative sex without a condom, injection drug use, needle sharing, and crack pipe sharing, were reported by 207/270 (76.7%) members of the cohort (see Table S5 in the data supplement). Injection drug use was more prevalent in those at risk of spreading HCV, HIV, or HBV than those not at risk (p<0.001). Of those who had injected in the previous month, 109/146 (74.7%) reported using the supervised injecting facility.

Multimorbidity

Of the 12 illnesses evaluated in greater detail, the median multimorbidity score (the sum of illnesses present) was 3 (Figure 1), with an interquartile range of 2–4. The median multimorbidity burden was 3 for both male and female participants and was not correlated with age (Spearman ra=0.06). Greater multimorbidity was correlated with lower scores on the Role Functioning Scale (ra=−0.21, p<0.001; N=289) and the Social and Occupational Functioning Assessment Scale (ra=−0.20, p<0.001; N=290). This finding was similar when the sample was limited to those with complete data for all 12 multimorbidity assessments, including MRI and serology (Role Functioning Scale: ra=−0.22, p=0.001; Social and Occupational Functioning Assessment Scale: ra=−0.23, p<0.001; N=215).

FIGURE 1. Multimorbidity in Tenants Living in Single-Room Occupancy Hotelsa

a Panel A shows the distribution of total multimorbid illnesses (0–12) in the cohort. The lower part of the panel shows the percentage of participants with increasing multimorbidity for each of the 12 conditions assessed. Since only three participants had persistent HBV infection, there is no bar to represent this group. Two of these participants scored +3, and one scored +4. Panel B shows the relationship between multimorbidity (0–12), scores on the Role Functioning Scale, and the number of participants at each intersection of multimorbidity number and level of function. The Role Functioning Scale comprises four items (work productivity, independent living [self-care], immediate social network relationships, and extended social network relationships); each item is scored on a scale of 1 to 7, with higher scores indicating better functioning. HCV=hepatitis C virus; qPCR=quantitative polymerase chain reaction.

The prevalence of treatment of three illnesses—psychosis (32.6%), opioid dependence (49.6%), and AIDS (61.5%)—was suboptimal (Table 4). Participants with psychosis with multimorbidity (opioid dependence and/or HIV/AIDS) were less than half as likely to have their psychosis treated than those with psychosis alone (p=0.003). In contrast, the presence of multimorbidity did not influence the likelihood of treatment for opioid addiction or HIV/AIDS.

TABLE 4. Treatment of Opioid Addiction, Psychosis, or HIV/AIDS Among Single-Room Occupancy Hotel Tenants
Treatment ProvidedN%
Antipsychotic medication
 Of total number with psychosis (N=135)4432.6
  Without opioid dependence or HIV/AIDS multimorbidity (N=64)2945.3
  With opioid dependence or HIV/AIDS multimorbidity (N=71)1521.1a
Methadone
 Of total number with opioid dependence (N=113)5649.6
  Without psychosis or HIV/AIDS multimorbidity (N=52)2446.0
  With psychosis or HIV/AIDS multimorbidity (N=61)3252.5
Antiretroviral medication
 Of total number with HIV/AIDS treatment indicated (N=52)3261.5
  Without opioid dependence or psychosis multimorbidity (N=16)956.3
  With opioid dependence or psychosis multimorbidity (N=36)2363.9

a Significant difference from participants without multimorbidity, p=0.003.

TABLE 4. Treatment of Opioid Addiction, Psychosis, or HIV/AIDS Among Single-Room Occupancy Hotel Tenants
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At baseline, participants who subsequently died had a greater multimorbidity score (median=4) than those who were alive at follow-up (median=3); however, this difference was not statistically significant.

Discussion

In our sample, participants with a high prevalence of previous homelessness and considerable social disadvantage living in marginal housing had a high level of mortality. Substance dependence, mental and neurological illnesses, and infectious diseases were common. Drug dependence played a direct role in one-third of deaths; most others represented complex multimorbidity. Greater multimorbidity was associated with poorer psychosocial functioning. The high level of directly observed mortality among persons living in single-room occupancy hotels is consistent with findings from analyses of administrative data sets comprised of persons living in similar circumstances in Canada (8) and is similar to data reported for those living in literal homelessness in the United States and Scandinavia (6, 7, 45).

In the community setting of our sample, there are approximately 7,100 single-room occupancy hotel rooms, and there are an estimated 1,600 homeless persons living on the street or in shelters (46). A recent study of street and shelter homelessness in Vancouver found an ethnic and educational background similar to that in our sample, with a slightly younger mean age (38.0 years compared with 44.1 years) and a larger proportion of women (37.2% compared with 23.3%) (47). Two-thirds of our sample had a history of homelessness. We cautiously suggest that many of the present findings may be relevant to the Vancouver homeless population and perhaps other homeless populations. However, obtaining the comprehensive evaluations reported, including detailed review of medical and psychiatric records, neurological examination, MRI, and neuropsychological testing, as well as serology and liver function testing to allow diagnosis of multimorbidity, makes replication of our study challenging.

Substance dependence was nearly universal. Dependence on cocaine or methamphetamine has long been associated with psychotic symptoms (48, 49). The estimated prevalence of psychosis in our sample (47.4%) was higher than the estimated prevalence in a meta-analysis of studies of the homeless (12.7%) (11). However, our estimate of the prevalence of schizophrenia and schizoaffective disorder was 12.6%, consistent with the meta-analysis and with a recent study using the Mini-International Neuropsychiatric Interview for diagnosis in a sample of homeless persons in three cities in our province (47). The findings from urine drug screens were consistent with the high prevalence of substance-induced psychosis in our sample, contributing to the high overall prevalence of psychosis. Although the prevalence of schizophrenia and related psychotic illness was still high in absolute terms, only a minority of those with psychosis represented mentally ill patients who had previously been cared for in an asylum or similar institutional setting.

Neurological illness was also common. The high frequency of movement disorders is likely related to stimulant drug use as well as exposure to antipsychotic drugs (50, 51). However, most participants with stimulant dependence in our study did not have movement disorders. The prevalence of brain infarctions that we observed appears to be similar to reported rates for healthy persons ages 30–49 (9.1% in the present study compared with 4%−9% in other reports) but higher for those ages 50–59 (19.3% compared with <9%) and 60–69 (18.2% compared with <12%) (44, 52). The high prevalence of crack cocaine use in our cohort may have contributed to risk for brain infarction (53, 54). Those with MRI evidence of infarction did not have elevated rates of seizures, movement disorders, or clinically obvious cognitive impairment. The relatively high rate of aneurysms may be related to stimulant dependence (55, 56). Most aneurysms were not in a size range or location associated with risk of rupture (57); however, ongoing use of stimulants could modify the predictive value of anatomical risk factors. The broadest definition of TBI yielded a high prevalence, similar to that reported for people living in homeless shelters (16). More narrowly defined TBI was more likely to be associated with ongoing symptoms, such as seizures or cognitive impairment, in contrast to brain infarctions that appeared relatively silent.

The very high rates of HIV and HCV in our cohort were similar to those reported in a previous study of people living in the same neighborhood (58). The high rate of previous successful treatment for HIV/AIDS confirms that with appropriately deployed strategies, patients with HIV/AIDS are amenable to therapeutic intervention (4). However, the rates of ongoing treatment were disappointing, although not as low as those for treatment of opioid dependence and psychosis. Infection with HCV was least likely to be treated (58), even in the presence of relatively high rates of participants with elevated biomarkers suggesting fibrosis or cirrhosis. This finding is consistent with findings from other reports indicating that social disadvantage, poor health literacy, and disengagement from the health care system are risk factors for low likelihood of treatment of HCV (19). Of additional concern, behaviors increasing the risk of spreading infection were common. As oral drug treatments for HCV become available, a greater emphasis should be placed on the challenges of delivering this care in a population with multimorbid illness (19). In particular, the high prevalence of stimulant use, the absence of substitution treatment analogous to methadone, and the potential difficulties accessing care in the face of ongoing psychosis and other mental illness will require the development of comprehensive strategies, perhaps modified from those proposed for opioid addiction and HIV infection (59).

Multimorbidity was highly prevalent, with co-occurring substance dependence, mental and neurological illnesses, and infectious diseases. Multimorbidity is reported to increase in association with greater socioeconomic deprivation (10). Even within the narrowed range of severe social deprivation in our cohort of persons living in single-room occupancy hotels, greater multimorbidity was associated with poorer psychosocial function. Multimorbidity was also associated with a lower likelihood of treatment of psychosis but not opioid dependence or HIV. Internationally, in the overall population, more severe mental illnesses, such as bipolar disorder, are more likely to be treated than less severe illnesses (60). This relationship may break down in the face of multimorbidity between mental illness, substance dependence, and physical illness.

The opportunity to investigate a reasonably large cohort of persons living with social disadvantage in single-room occupancy hotels was the unique feature of our study. Other investigators have described the challenges of gaining access to single-room occupancy hotels and other types of marginal housing, resulting in a paucity of information on the health status of tenants (5). While we cannot be certain that our observations generalize to other settings, many clinicians in urban practice are familiar with smaller numbers of individuals in public clinics with similar multimorbidity. Local assessment of specific health needs in marginally housed populations may be as important as locally based assessment in the homeless (11). Although we attempted to be thorough and detailed with our assessment and analysis strategy, undoubtedly other illnesses were missed, and the psychiatric diagnoses could change over time. Our sample of women was likely too small to permit informative sex-based analyses. Finally, our assessment of mortality had at least two limitations. Although only 11% of participants could not be followed up for at least 6 months, we were unable to systematically search death records or coroner’s reports to determine whether these individuals had died. If some of those lost to follow-up had died, our standardized mortality rate might be too conservative. Second, although none of the outside-of-hospital deaths in our sample were attributed to suicide, this cause of death may be underestimated. Four of the seven participants who died outside hospital settings were seen at least 1 month before death, and none expressed suicidal ideation according to the previously described criteria. However, since five of these seven deaths were attributed to overdoses, excluding suicide as a cause is difficult.

In conclusion, mortality was high in this cohort of persons living in marginal housing. Multimorbidity was common, and provision of treatment was inadequate. Collaborative care strategies may have a role in improving the health of persons living in these circumstances and needs to be investigated (61, 62).

From the Departments of Psychiatry, Radiology, Anesthesia, Pharmacology and Therapeutics, Pathology and Laboratory Medicine, Medicine, and the School of Population and Public Health, University of British Columbia, Vancouver, Canada; and the Department of Psychology, Simon Fraser University, Burnaby, Canada.
Address correspondence to Dr. Honer ().

Dr. Lang receives operating funding from the British Columbia Mind Foundation, Canadian Institutes of Health Research, and Provincial Health Services Authority. Dr. Barr has received consulting fees or sat on paid advisory boards for Bristol-Myers Squibb, Eli Lilly, and Roche. Dr. Procyshyn has received speaking and advisory panel fees from AstraZeneca, Bristol-Myers Squibb, Janssen, Otsuka, Pfizer, and Sunovion. Dr. Krajden has received research grant support from Gen-Probe, Merck Canada, Roche, and Siemens. Dr. Krausz has received research grant support from Bell Canada, the British Columbia Mental Health and Addictions Services, the Canadian Institutes of Health Research, the Carraresi Foundation, and the InnerChange Foundation; he has also received travel support and fees from the Canadian Centre on Substance Abuse, the Graham Boeckh Foundation, the Swiss Federal Health Authority, and the United Nations Children’s Fund. Dr. Montaner has received financial support from the Bill and Melinda Gates Foundation, the French National Agency for Research on AIDS and Viral Hepatitis, the International AIDS Society, the National Institute of Allergy and Infectious Diseases, the National Institutes of Health Research-Office of AIDS Research, Providence Health Care and Vancouver Coastal Health Authority, the Public Health Agency of Canada, Simon Fraser University, the United Nations AIDS Program, the United States President’s Emergency Plan for AIDS Relief, the University of British Columbia, and the World Health Organization; and he has received research grant support from Abbott, Biolytical, Boehringer-Ingelheim, Bristol-Myers Squibb, Gilead Sciences, Janssen, Merck, and ViiV Healthcare. Dr. MacEwan has received consulting fees or served on paid advisory boards for Apotex, AstraZeneca, Bristol-Myers Squibb, Janssen, Lundbeck, Otsuka, Pfizer, and Sunovion; he has also received lecture fees from AstraZeneca, Bristol-Myers Squibb, Eli Lilly, Janssen, and Otsuka and research grant support from Janssen Pharmaceuticals. Dr. Honer has received consulting fees from or served on paid advisory boards for In Silico, Lundbeck, MDH Consulting, Novartis, and Roche; he has received honoraria from the British Columbia Schizophrenia Society, the Canadian Agency for Drugs and Technology in Health, the Centre for Addiction and Mental Health (Toronto), the Fraser, the Korean Society for Schizophrenia Research, Providence Health Care and Vancouver Coastal Health Authority, and Rush University; and he has received research grant support from the Canadian Institutes of Health Research. All other authors report no financial relationships with commercial interests.

Supplementary Material

Supported by the Canadian Institutes of Health Research (grant CBG-101827); by a fellowship from the British Columbia Mental Health and Addictions Services (to Dr. Vila-Rodriguez); and by the British Columbia Mental Health and Addictions Services (an Agency of the Provincial Health Services Authority), through an avant-garde award (number, 1DP1DA026182-01) from the U.S. National Institute on Drug Abuse (to Dr. Montaner), and through a Knowledge Transfer Award from the Canadian Institutes of Health Research (to Dr. Montaner).

The authors thank the Portland Hotel Society, Vancouver, and Drs. Cai Song, Igor Grant, Eric Chen, and Peter Falkai.

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