Outcomes Among Persons with HIV Following a Mental Health Admission: A Population-Based Study

Abstract

To compare outcomes following psychiatric hospitalization between people with and without HIV. Population-based study of people with (n = 1,089) and without (n = 280,888) HIV who were hospitalized for psychiatric illness between January 1, 2006 and December 31, 2014. Overall, 9 (0.8%) people with HIV died within 30 days of discharge, compared with 3,710 (1.3%) HIV-negative individuals. Following multivariable adjustment, there was no difference in the risk of readmission or emergency department (ED) visits for psychiatric illness in the 90 days following discharge. Conversely, people with HIV were at higher risk of ED visits for substance use disorders and less likely to receive psychiatry follow-up during this period. HIV is associated with ED use for substance use disorders and less psychiatry follow-up within 90 days of hospital discharge for psychiatric illness. Interventions facilitating continuity of care following discharge are warranted.

Introduction

Psychiatric illness is a common comorbid condition among people with HIV, with several studies noting a higher prevalence of anxiety, mood, and substance use disorders relative to the general population.^1,2 In addition to being associated with reduced quality of life, antiretroviral nonadherence, and poor retention in HIV care, psychiatric illness is a common cause of hospitalization in this population.^3

–10 Furthermore, recurrence of illness is common, with 43% of patients in one Canadian study experiencing additional episodes of depression during 2 years of follow-up.¹¹ Despite the prevalence and severity of psychiatric illness in people with HIV, several studies have observed that access to mental healthcare is suboptimal for these patients^12,13 and that ∼50% do not receive care consistent with existing treatment guidelines.¹⁴

Yet, apart from a single study demonstrating that people with HIV are at higher risk for psychiatric readmission following hospital discharge than HIV-negative individuals (21.7% vs. 14.2%),¹⁵ to our knowledge there have been no studies characterizing outcomes and health service use following a psychiatric admission, including death, emergency department (ED) use, and psychiatrist follow-up in this population. Such studies are important for several reasons. First, because suicide risk is high in the period immediately following a psychiatric illness-related hospital discharge and rates of suicide in people with HIV are nearly threefold those of the general population, identifying whether HIV imparts a higher risk of death shortly after discharge is necessary to inform inpatient management and outpatient follow-up of these patients.^16

–19 Second, differences in the risk of psychiatric illness-related readmission or ED visits following discharge between people with and without HIV may represent disparities in continuity of outpatient care or severity of underlying psychiatric illness.²⁰ Third, timely follow-up with a psychiatrist following discharge can optimize drug therapy, reinforce adherence, and promote access to additional support services, such as outpatient psychotherapy.^20,21 In addition, people with HIV are disproportionately represented in low income strata,^22,23 a finding that is relevant to postpsychiatric hospitalization discharge outcomes because of socioeconomic gradients in access to mental healthcare, including psychiatry, which favor high income individuals.^24,25 In this context, examining clinical outcomes and health service use in the period immediately following psychiatric illness-related hospital discharge in people with HIV is required to understand whether gaps exist in care. Accordingly, we compared postpsychiatric hospitalization discharge outcomes and health service use between adults living with and without HIV.

Materials and Methods

Setting

We conducted a population-based study comparing the risk of death and health service use following discharge from hospital for psychiatric illness among people living with and without HIV in Ontario between January 1, 2006 and December 31, 2014. This study was approved by the institutional review board at Sunnybrook Health Sciences Centre, Toronto, Canada.

Data sources

We used Ontario's administrative health databases, which are securely linked using unique encoded identifiers and analyzed at the Institute for Clinical Evaluative Sciences (ICES, www.ices.on.ca). We identified adults living with HIV using the Ontario HIV Database, an administrative data registry of Ontario residents with diagnosed HIV infection, which was generated using a validated case-finding algorithm.²⁶ The definition of three physician claims with an International Classification of Diseases, Ninth Revision code for HIV infection (042, 043, 044) within a 3-year period has a sensitivity and specificity of 96.2% [95% confidence intervals (CI) 95.2–97.9] and 99.6% (95% CI 99.1–99.8), respectively, for identifying persons living with HIV. We identified hospital admissions for psychiatric illness, including substance use disorders, using the Ontario Mental Health Reporting System (OMHRS) database, which includes information regarding patients discharged from adult-designated inpatient mental health beds in general, provincial psychiatric and specialty psychiatric facilities in Ontario, and the Canadian Institute for Health Information Discharge Database (CIHI-DAD), which contains detailed clinical records on all hospital admissions in Ontario. Together, the OMHRS database and CIHI-DAD capture all hospitalizations in Ontario. We identified ED room visits using the Canadian Institute for Health Information National Ambulatory Care Reporting System (NACRS) database and used the Ontario Health Insurance Plan (OHIP) and ICES Physician databases to identify claims for physician services and visits to psychiatrists. We obtained basic demographic data from the Registered Persons Database, a registry of all Ontario residents eligible for health insurance. These databases are routinely used to examine mental health outcomes and health service use.^27,28

Study population

We identified all adults aged 18 years and older with a hospital admission for psychiatric illness between January 1, 2006 and December 31, 2014 using the OMHRS database and CIHI-DAD. For individuals with more than one admission during the study period, we selected only the first for analysis. From within this cohort, we identified individuals diagnosed with HIV using the Ontario HIV database. Individuals with a psychiatric admission who did not have an HIV diagnosis comprised the control group.

Outcomes

The primary outcome was death at 30 days following discharge among individuals who survived their admission. In secondary analyses, we compared the cumulative incidence of readmission to hospital for psychiatric illness, ED visits for psychiatric illness, and outpatient psychiatry follow-up, all within 90 days of hospital discharge. Because substance use disorders in people with HIV have been associated with increased mortality, delayed initiation of antiretroviral therapy, and increased HIV transmission behaviors,^29
–31 we also evaluated readmissions and ED visits for substance use disorders separately. For all secondary analyses, we excluded individuals who died during admission and followed the remaining patients from date of discharge up to 90 days until the occurrence of each of the outcomes, death, or end of the study period (March 31, 2015), whichever occurred first.

Statistical analysis

We computed standardized differences (SD) to examine intergroup balance in the distribution of baseline variables. SD of less than 0.1 indicate good balance between groups for a given covariate.³²

For the primary outcome, we compared the proportion of patients with and without HIV who died in the first 30 days following discharge using penalized logistic regression. Next, we computed the cumulative incidence of each secondary outcome and used multivariable Cox proportional models to examine the association between HIV and each outcome, using HIV-negative individuals as the reference group. We adjusted models for variables that could influence the risk of death and occurrence of a secondary outcome, including patient age and sex, urban versus rural residence, socioeconomic status, visit with a psychiatrist in the year preceding admission, comorbidity burden in the year preceding admission, number of visits to a primary care physician in the preceding year, length of admission and prior hospitalization for schizophrenia and nonorganic psychotic disorders, substance use disorders, mood and affective disorders, deliberate self-harm, personality disorders or anxiety disorders at any time before 2006, and the start date of the current study. We determined patient socioeconomic status at the neighborhood level using postal code information and Statistics Canada census data. We used the Johns Hopkins Adjusted Clinical Groups Case-Mix System to adjust for differences in comorbidity burden. This system uses diagnostic information from administrative databases to describe and predict use of healthcare resources. In this study, we used Aggregated Diagnosis Groups (ADGs), which are clusters of diagnostic codes that are similar in terms of severity and expected persistence.³³ The number of ADGs ranges from 0 to a maximum of 32, with a higher number reflecting a higher level of comorbidity. We also stratified analyses by sex to explore heterogeneity in health service use among women and men. All analyses were conducted using SAS version 9.4 (SAS Institute, Cary, NC).

Results

We studied 280,888 individuals with a psychiatric admission, of whom 1,089 (0.39%) were HIV positive. Compared with HIV-negative individuals, persons with HIV were predominantly male (79.2% vs. 50.3%; SD = 0.64), disproportionately represented in the lowest income neighborhoods (35.9% vs. 27.4%; SD = 0.18), less likely to live in rural settings (3.8% vs. 13.5%; SD = 0.35), and more likely to be admitted for substance use disorder (31.2% vs. 16.3%) (Table 1).

Table 1.

Baseline Characteristics of Patients With HIV and Without HIV Following a Hospitalization for Psychiatric Illness, 2006–2014

Variable	HIV (n = 1,089)	No HIV (n = 279,799)	Standardized difference
Age (mean ± SD)	42.49 ± 10.92	49.23 ± 21.22	0.4
Female, n (%)	226 (20.8)	139,156 (49.7)	0.64
Age category, n (%)
18–25	58 (5.3)	44,054 (15.7)	0.34
26–35	209 (19.2)	42,594 (15.2)	0.11
36–45	425 (39.0)	47,631 (17.0)	0.51
46–55	295 (27.1)	48,407 (17.3)	0.24
>56	102 (9.4)	97,113 (34.7)	0.64
Income quintile, n (%)
1 (lowest)	391 (35.9)	76,762 (27.4)	0.18
2	234 (21.5)	59,200 (21.2)	0.01
3	156 (14.3)	50,547 (18.1)	0.1
4	146 (13.4)	47,916 (17.1)	0.1
5 (highest)	144 (13.2)	42,994 (15.4)	0.06
Missing	18 (1.7)	2,380 (0.9)	0.07
Rural residence, n (%)
No	1,043 (95.8)	241,606 (86.3)	0.34
Yes	41 (3.8)	37,657 (13.5)	0.35
Missing	≤5 (0.5)	536 (0.2)	0.05
Number of primary care visits in year before cohort entry (mean ± SD)	10.94 ± 14.00	7.66 ± 10.06	0.27
Number of ADGs in 1 year before cohort entry (mean ± SD)	7.74 ± 4.09	6.08 ± 3.79	0.42
Past hospitalizations for mental health illness, n (%)
Schizophrenia/nonorganic psychotic disorders	39 (3.6)	9,202 (3.3)	0.02
Substance use disorders	132 (12.1)	13,985 (5.0)	0.26
Mood/affective disorders	104 (9.6)	18,036 (6.4)	0.11
Deliberate self-harm	16 (1.5)	3,058 (1.1)	0.03
Other personality disorders	32 (2.9)	4,772 (1.7)	0.08
Anxiety disorders	40 (3.7)	8,530 (3.0)	0.03
Any diagnosis	215 (19.7)	36,490 (13.0)	0.18
Seen psychiatrist in prior year	475 (43.6)	82,295 (29.4)	0.3
Length of stay
Median (IQR)	6 (2–19)	7 (2–18)	0.1
Reason for admission, n (%)
Substance-related disorder	340 (31.2)	45,476 (16.3)	0.36
Schizophrenia and delusional and nonorganic psychotic disorders	143 (13.1)	39,530 (14.1)	0.03
Mood/affective disorders	310 (28.5)	85,719 (30.6)	0.05
Anxiety disorders	31 (2.8)	12,311 (4.4)	0.08
Dementia	29 (2.7)	25,646 (9.2)	0.28
Deliberate self-harm	49 (4.5)	15,740 (5.6)	0.05
Other (adult personality and behavior)	86 (7.9)	17,911 (6.4)	0.06
Unknown	101 (9.3)	37,466 (13.4)	0.13

ADG, Aggregated Diagnosis Group.

Overall, 9 (0.8%) patients with HIV died within 30 days of discharge, compared with 3,710 (1.3%) HIV-negative individuals [unadjusted odds ratio 0.61, 95% CI (0.32–1.18)]. Because of the small number of events in people with HIV and associated concerns of model overfitting and lack of precision, we did not perform multivariable analysis.

In secondary analyses, the cumulative incidence of readmission for psychiatric illness was similar among people with (0.14; 95% CI 0.12–0.16) and without (0.13; 95% CI 0.13–0.13) HIV. In contrast, the cumulative incidence of ED visits for psychiatric illness was higher in people with HIV (0.20; 95% CI 0.17–0.22) relative to HIV-negative individuals (0.15; 95% CI 0.15–0.15). Similarly, the cumulative incidence of ED visits for substance use disorders within 90 days was higher in people with HIV (0.12; 95% CI 0.10–0.14) relative to HIV-negative individuals (0.04; 95% CI 0.04–0.04). Respective estimates for readmissions for substance use disorders were 0.05 (95% CI 0.04–0.06) and 0.02 (95% CI 0.02–0.02). Following multivariable adjustment, there were no differences between people living with and without HIV in readmission [hazard ratio (HR) 0.92; 95% CI 0.78–1.08] or ED visits for psychiatric illness (HR 1.02; 95% CI 0.89–1.17) (Table 2). Results were similar when stratified by sex (Tables 3 and 4). Similarly, the relative hazard for readmission for substance use disorders between people with and without HIV was 1.21 (95% CI 0.93–1.59). In contrast, people with HIV were at higher risk for substance use disorder-related ED visits (HR 1.40; 95% CI 1.17–1.68). In analyses stratified by sex, women with HIV were at higher risk for readmissions (HR 2.26; 95% CI 1.38–3.70) and ED visits for substance use disorder (HR 2.01; 95% CI 1.39–2.90) relative to HIV-negative women (Table 3). Among men, no differences were observed for readmission for substance use disorders (HR 1.04; 95% CI 0.75–1.43), whereas HIV was associated with substance use related ED visits (HR 1.27; 95% CI 1.03–1.56) (Table 4).

Table 2.

Hazard Ratios for Psychiatric Illness-Related Readmission, Psychiatric Illness-Related Emergency Department Visit, and Postdischarge Psychiatry Follow-Up, Within 90 Days of Discharge

	Cumulative incidence HIV (95% confidence intervals)	Cumulative incidence non-HIV (95% confidence intervals)	Unadjusted hazard ratio (95% confidence intervals)	Adjusted hazard ratio (95% confidence intervals) ^a
Readmission for mental health illness	0.14 (0.12–0.16)	0.13 (0.13–0.13)	1.10 (0.94–1.29)	0.92 (0.78–1.08)
ED visit for mental health illness	0.20 (0.17–0.22)	0.15 (0.15–0.15)	1.36 (1.18–1.55)	1.02 (0.89–1.17)
Readmission for substance use disorder	0.05 (0.04–0.06)	0.02 (0.02–0.02)	2.18 (1.67–2.85)	1.21 (0.93–1.59)
ED visit for substance use disorder	0.12 (0.10–0.14)	0.04 (0.04–0.04)	2.71 (2.26–3.24)	1.40 (1.17–1.68)
Psychiatry follow-up	0.49 (0.46–0.52)	0.46 (0.46–0.47)	1.07 (0.99–1.17)	0.90 (0.83–0.98)

Adjusted for age, sex, ADGs, rurality, income quintile, number of primary care visits in the past year, visit with a psychiatrist in the past year, schizophrenia, mood/affective disorder, substance use, other adult personality and behavioral disorders, and anxiety disorder.

ED, emergency department.

Table 3.

Hazard Ratios For Psychiatric Illness-Related Readmission, Psychiatric Illness-Related Emergency Department Visit, and Postdischarge Psychiatry Follow-Up, Within 90 Days of Discharge, Women Only

	Cumulative incidence HIV (95% confidence intervals)	Cumulative incidence non-HIV (95% confidence intervals)	Unadjusted hazard ratio (95% confidence intervals)	Adjusted hazard ratio (95% confidence intervals)^a
Readmission for mental health illness	0.12 (0.09–0.17)	0.12 (0.12–0.13)	1.02 (0.70–1.48)	0.84 (0.58–1.22)
ED visit for mental health illness	0.23 (0.17–0.28)	0.14 (0.14–0.14)	1.68 (1.28–2.22)	1.24 (0.94–1.63)
Psychiatry follow-up	0.48 (0.41–0.54)	0.49 (0.48–0.49)	0.97 (0.80–1.17)	0.83 (0.69–1.01)
Readmission for substance use disorder	0.07 (0.04–0.11)	0.02 (0.02–0.02)	4.62 (2.82–7.54)	2.26 (1.38–3.70)
ED visit for substance use disorder	0.13 (0.09–0.18)	0.03 (0.03–0.03)	4.58 (3.18–6.60)	2.01 (1.39–2.90)

Table 4.

Hazard Ratios for Psychiatric Illness-Related Readmission, Psychiatric Illness-Related Emergency Department Visit, and Postdischarge Psychiatry Follow-Up, Within 90 Days of Discharge, Men Only

	Cumulative incidence HIV (95% confidence intervals)	Cumulative incidence non-HIV (95% confidence intervals)	Unadjusted hazard ratio (95% confidence intervals)	Adjusted hazard ratio (95% confidence intervals)^a
Readmission for mental health illness	0.15 (0.12–0.17)	0.13 (0.13–0.13)	1.09 (0.92–1.31)	0.94 (0.78–1.12)
ED visit for mental health illness	0.19 (0.16–0.21)	0.15 (0.15–0.16)	1.24 (1.06–1.45)	0.95 (0.81–1.11)
Psychiatry follow-up	0.49 (0.46–0.52)	0.44 (0.44–0.45)	1.15 (1.05–1.27)	0.93 (0.84–1.02)
Readmission for substance use disorder	0.04 (0.03–0.06)	0.03 (0.03–0.03)	1.47 (1.07–2.02)	1.04 (0.75–1.43)
ED visit for substance use disorder	0.11 (0.09–0.13)	0.06 (0.06–0.06)	1.97 (1.61–2.42)	1.27 (1.03–1.56)

The cumulative incidence of psychiatry follow-up within 90 days was comparable between people with (0.49; 95% CI 0.46–0.52) and without HIV (0.46; 95% CI 0.46–0.47). Following multivariable adjustment, HIV was inversely associated with postdischarge psychiatry follow-up (HR 0.90; 95% CI 0.83–0.98) (Table 2).

Discussion

In our population-based study, we found no association between HIV and death in the 30 days following discharge and a slightly smaller proportion of deaths during this window among people with HIV relative to HIV-negative individuals. This finding may reflect greater preexisting connections with mental health services by people with HIV in the year preceding admission, as these individuals had more contact with primary care providers were more likely to see a psychiatrist in the year before admission relative to HIV-negative individuals. In addition, Ontario residents with HIV may access counseling through venues not available to HIV-negative individuals, such as AIDS Service Organizations and psychiatric clinics specialized in caring for people with HIV. Although we did not have cause of death data, these services may mitigate suicidal behaviors in people with HIV. However, our findings regarding mortality should be interpreted cautiously, because the number of events in people with HIV was small, and we did not perform multivariable analysis due to concerns regarding lack of precision and model overfitting. In secondary analyses, HIV was not associated with a greater risk of readmission or ED visits for psychiatric illness within 90 days of discharge. However, people with HIV were less likely to see a psychiatrist within 90 days of discharge and were at greater risk for ED room visits for substance use disorders during this period. This finding was especially notable among women with HIV, who were also at greater risk of readmission for substance use disorder than HIV-negative women.

Several mechanisms may explain our findings. The high risk of readmission and ED use for substance use disorders among women with HIV likely reflects intersecting social inequalities and structural barriers to community-based care that disproportionately affect women relative to men. Specifically, women with substance use disorders report higher levels of stigma and discrimination from healthcare workers than men, experiences which may be amplified by HIV-related stigma and deter help seeking and linkage with care following discharge.^34
–36 Furthermore, gender-based violence is up to five times more common among women with substance use disorders relative to the general female population^37
–39 and may be more severe among women with HIV relative to HIV-negative women.^40
–42 Gender-based violence limits participation in drug treatment services, access to HIV care, and antiretroviral adherence.^43

–46 In addition, harm reduction and drug treatment services may be less physically accessible to women, particularly those who engage in sex work, which often occurs in locations remote to these services.⁴⁷ Developing interventions, which integrate the management of substance use disorders and HIV, is warranted to facilitate continuity of care following hospital discharge and prevent early psychiatric readmission and ED use. Several studies suggest that further integration of trauma-focused interventions addressing gender-based violence and associated post-traumatic stress disorder augments the effectiveness of such programs in women.^48
–50

We also observed higher hazards for ED visits related to substance use disorders among men with HIV relative to HIV-negative men. This finding is consistent with literature documenting a higher prevalence of problematic drug use among a cohort of predominantly male veterans with HIV relative to demographically matched HIV-negative patients.^51,52 Furthermore, intimate partner violence among men who have sex with men occurs at rates similar to those of women and has been associated with substance use and hospitalization among HIV-infected gay and bisexual men.^53
–55 Although we lacked information regarding sexual orientation, men who have sex with men represent over 80% of HIV diagnoses among men in Ontario.⁵⁶ It is therefore conceivable that intimate partner violence is an important determinant of postdischarge ED use and hospitalizations among men with HIV and that associated screening and support be considered as a component of postdischarge care for this population.

The inverse association between HIV and psychiatry follow-up that emerged following multivariable adjustment likely reflects unmeasured interacting factors that create social disadvantage among people with HIV, including lack of housing, transportation to services, and income.^57
–59 HIV imparts an additional layer of stigma to that imposed by mental health illness, which may further compromise access to care.⁶⁰ Interventions such as postdischarge telephone follow-up and home visits by nurses and transition managers who facilitate outpatient follow-up have been effective in other settings and warrant examination in people with HIV.⁶¹ Because HIV and psychiatric care are often provided in different settings, integration strategies such as co-location of services should be considered to prevent fragmentation of care.

Our findings are strengthened by the population-based nature of our data, thereby allowing us to examine all Ontario residents hospitalized with psychiatric illness during the study period. However, several limitations merit emphasis. We used administrative datasets and had no information on variables that may influence outcomes and health service use following discharge, including housing status, food security, and sexual orientation.⁶² Similarly, we did not have reliable medication data. In addition, we could not identify care delivered by nurses, counselors, or psychologists. Future studies utilizing clinical cohorts that capture a variety of individual-level data, including social determinants of health and mental healthcare delivered by nonphysicians, could address these limitations and complement our work. Such analyses will also permit greater examination of other factors involved in postpsychiatric discharge outcomes among people with HIV. Because we conducted multiple analyses, spurious associations are possible. The large difference in sample size between people with and without HIV may increase the risk of a Type II error. Finally, we could not ascertain cause of death; however, we selected a 30-day observation window to increase the likelihood that death was related to the psychiatric admission.

In conclusion, our study suggests that people with HIV are at higher risk for substance use disorder-related ED use in the 90 days following discharge relative to HIV-negative individuals, a finding that is especially pronounced among women with HIV, among whom a higher risk of readmission for substance use disorders was also observed. In addition, we found an inverse association between HIV and postdischarge psychiatry follow-up after multivariable analysis, although the cumulative incidence of psychiatry use was low in both persons with and without HIV. In light of these findings, our results support the implementation and evaluation of interventions which facilitate postdischarge transition to care for all individuals following hospital discharge for psychiatric illness and the integration of HIV, harm reduction, mental health, and trauma-focused services for people with HIV.

Footnotes

Acknowledgments

This study was funded by the Ontario HIV Treatment Network (grant no. JIDA 862) and the Institute for Clinical Evaluative Sciences (ICES), which is funded by an annual grant from the Ontario Ministry of Health and Long-Term Care (MOHLTC). The sponsors had no role in the design or conduct of the study; in the collection, analysis, or interpretation of the data; or in the preparation, review, or approval of the article. The opinions, results, and conclusions reported in this article are those of the authors and are independent from the funding source. No endorsement by ICES or the Ontario MOHLTC is intended or should be inferred. T.A. and C.E.K. are supported by a New Investigator Awards from the Canadian Institutes for Health Research-Ontario HIV Treatment Network. M.L. is the recipient of salary support from Women's College Hospital, the University of Toronto, and the Women's College Research Institute. A.M.B. is supported by the Fondation Alma and Baxter Ricard Chair in Inner City Health at St. Michael's Hospital, Toronto, Canada and the University of Toronto.

Authors' Contributions

All authors contributed to the concept and design of the study. C.L. and T.A. acquired the data, and all authors were involved in the analysis and interpretation of the data. C.L. and T.A. drafted the article, and all authors were involved in critical revision of the article. All authors approved the article submitted for publication. C.L. and T.A. provided administrative, technical, or material support. T.A. is the guarantor for the article.

Author Disclosure Statement

M.L. has served on advisory boards and spoken at CME events for ViiV Healthcare, AbbVie, Merck Canada, Inc., and Gilead Sciences. For the remaining authors no competing financial interests exist.

References

Kendall

, Wong

, Taljaard

, et al.: A cross-sectional, population-based study measuring comorbidity among people living with HIV in Ontario. BMC Public Health, 2014; 14:161.

Chandler

, Himelhoch

, Moore

: Substance abuse and psychiatric disorders in HIV-positive patients: Epidemiology and impact on antiretroviral therapy. Drugs, 2006; 66:769–789.

Uthman

, Magidson

, Safren

, et al.: Depression and adherence to antiretroviral therapy in low-, middle- and high-income countries: A systematic review and meta-analysis. Curr HIV/AIDS Rep, 2014; 11:291–307.

Springer

, Dushaj

, Azar

: The impact of DSM-IV mental disorders on adherence to combination antiretroviral therapy among adult persons living with HIV/AIDS: A systematic review. AIDS Behav, 2012; 16:2119–2143.

Mellins

, Kang

, Leu

, et al.: Longitudinal study of mental health and psychosocial predictors of medical treatment adherence in mothers living with HIV disease. AIDS Patient Care STDs, 2003; 17:407–416.

Zimpel

, Fleck

: Depression as a major impact on the quality of life of HIV-positive Brazilians. Psychol Health Med, 2014; 19:47–58.

Zuniga

, Yoo-Jeong

, Dai

, et al.: The role of depression in retention in care for persons living with HIV. AIDS Patient Care STDs, 2016; 30:34–38.

Moore

, Grulich

, Prestage

, et al.: Hospitalization for anxiety and mood disorders in HIV-infected and -uninfected gay and bisexual men. J Acquir Immune Defic Syndr, 2016; 73:589–597.

Crowell

, Gebo

, Blankson

, et al.: Hospitalization rates and reasons among HIV elite controlers and persons with medically controlled HIV infection. J Infect Dis, 2015; 211:1692–1702.

10.

Rentsch

, Tate

, Akgün

, et al.: Alcohol-related diagnoses and all-cause hospitalization among HIV-infected and uninfected patients: A longitudinal analysis of United States Veterans from 1997 to 2011. AIDS Behav, 2016; 20:555–564.

11.

Choi

SKY

, Boyle

, Cairney

, et al.: Prevalence, recurrence and incidence of current depressive symptoms among people living with HIV in Ontario, Canada: Results from the Ontario HIV Treatment Network Cohort Study. PLoS One, 2016; 11:e0165816.

12.

Cook

, Burke-Miller

, Grey

, et al.: Do HIV-positive women receive depression treatment that meets best practice guidelines?. AIDS Behav, 2014; 18:1094–1102.

13.

Weaver

, Conover

, Proescholdbell

, et al.: Utilization of mental health and substance abuse care for people living with HIV/AIDS, chronic mental illness, and substance abuse disorders. J Acquir Immune Defic Syndr, 2008; 47:449–458.

14.

Choi

SKY

, Boyle

, Cairney

, et al.: Adequacy of mental health services for HIV-positive patients with depression: Ontario HIV Treatment Network Cohort Study. PLoS One, 2016; 11:e0156652.

15.

Berry

, Fleishman

, Moore

, et al.: Thirty-day hospital readmissions for adults with and without HIV infection. HIV Med, 2016; 17:167–177.

16.

Olfson

, Wall

, Wang

, et al.: Short-term suicide risk after psychiatric hospital discharge. JAMA Psychiatry, 2016; 73:1119–1126.

17.

Jia

, Mehlum

, Qin

: AIDS/HIV infection, comorbid psychiatric illness, and risk for subsequent suicide: A nationwide register linkage study. J Clin Psychiatry, 2012; 73:1315–1321.

18.

Gurm

, Samji

, Nophal

, et al.: Suicide mortality among people accessing highly active antiretroviral therapy for HIV/AIDS in British Columbia: A retrospective analysis. CMAJ Open, 2015; 3:E140–E148.

19.

Keiser

, Spoerri

, Brinkhof

MWG

, et al.: Suicide in HIV-infected individuals and the general population in Switzerland, 1988–2008. Am J Psychiatry, 2010; 167:143–150.

20.

Anderson

, Kurdyak

: Factors associated with timely physician follow-up after a first diagnosis of psychotic disorder. Can J Psychiatry, 2017; 62:268–277.

21.

Beadles

, Ellis

, Lichstein

, et al.: First outpatient follow-up after psychiatric hospitalization: Does one size fit all?. Psychiatr Serv, 2015; 66:364–372.

22.

Gant

, Lomotey

, Hall

, et al.: A county-level examination of the relationship between HIV and social determinants of health: 40 states, 2006–2008. Open AIDS J, 2012; 6:1–7.

23.

Pellowski

, Kalichman

, Matthews

, et al.: A pandemic of the poor: Social disadvantage and the U.S. HIV epidemic. Am Psychol, 2013; 68:197–209.

24.

Steele

, Glazier

, Lin

: Inequity in mental health care under Canadian universal health coverage. Psychiatr Serv, 2006; 57:317–324.

25.

Durbin

, Bondy

, Durbin

: The association between income source and met need among community mental health service users in Ontario, Canada. Community Ment Health J, 2012; 48:662–672.

26.

Antoniou

, Zagorski

, Loutfy

, et al.: Validation of case-finding algorithms derived from administrative data for identifying adults living with human immunodeficiency virus infection. PLoS One, 2011; 6:e21748.

27.

Anderson

, Cheng

, Susser

, et al.: Incidence of psychotic disorders among first-generation immigrants and refugees in Ontario. CMAJ, 16; 187:E279–E286.

28.

Rochon-Terry

, Gruneir

, Seeman

, et al.: Hospitalizations and emergency department visits for psychiatric illness during and after pregnancy among women with schizophrenia. J Clin Psychiatry, 2016; 77:541–547.

29.

DeLorenze

, Weisner

, Tsai

, et al.: Excess mortality among HIV-infected patients diagnosed with substance use dependence or abuse receiving care in a fully integrated medical care program. Alcohol Clin Exp Res, 2011; 35:203–210.

30.

Rodríguez-Arenas

, Jarrín

, del Amo

, et al.: Delay in the initiation of HAART, poorer virological response, and higher mortality among HIV-infected injecting drug users in Spain. AIDS Res Hum Retroviruses, 2006; 22:715–723.

31.

Dirks

, Esser

, Borgmann

, et al.: Substance use and sexual risk behaviour among HIV-positive men who have sex with men in specialized out-patient clinics. HIV Med, 2012; 13:533–540.

32.

Austin

, Grootendorst

, Anderson

: A comparison of the ability of different propensity score models to balance measured variables between treated and untreated subjects: A Monte Carlo study. Stat Med, 2007; 26:734–753.

33.

The Johns Hopkins ACG System. Baltimore: Johns Hopkins University. Available at http://acg.jhsph.org, accessed June 12, 2017 .

34.

El-Bassel

, Terlikbaeva

, Pinkham

: HIV and women who use drugs: Double neglect, double risk. Lancet, 2010; 376:312–314.

35.

Azim

, Bontell

, Strathdee

: Women, drugs and HIV. Int J Drug Policy, 2015; 26(suppl 1):S16–S21.

36.

Blankenship

, Reinhard

, Sherman

, et al.: Structural interventions for HIV prevention among women who use drugs: A global perspective. J Acquir Immune Defic Syndr, 2015; 69(suppl 2):S140–S145.

37.

Moore

, Stuart

, Meehan

, et al.: Drug abuse and aggression between intimate partners: A meta-analytic review. Clin Psychol Rev, 2008; 28:247–274.

38.

El-Bassel

, Gilbert

, Witte

, et al.: Intimate partner violence and HIV among drug-involved women: Contexts linking these two epidemics–challenges and implications for prevention and treatment. Subst Use Misuse, 2011; 46:295–306.

39.

Devries

, Child

, Bacchus

, et al.: Intimate partner violence victimization and alcohol consumption in women: A systematic review and meta-analysis. Addiction, 2014; 109:379–391.

40.

Gielen

, Ghandour

, Burke

, et al.: HIV/AIDS and intimate partner violence: Intersecting women's health issues in the United States. Trauma Violence Abuse, 2007; 8:178–198.

41.

McDonnell

, Gielen

, O'Campo

: Does HIV status make a difference in the experience of lifetime abuse? Descriptions of abuse and its context among low-income urban women. J Urban Health, 2003; 80:494–509.

42.

Wyatt

, Myers

, Williams

, et al.: Does a history of trauma contribute to HIV risk for women of color? Implications for prevention and policy. Am J Public Health, 2002; 92:660–665.

43.

Center for Substance Abuse Treatment. Substance Abuse Treatment and Domestic Violence. Rockville (MD): Substance Abuse and Mental Health Services Administration (US); 1997. (Treatment Improvement Protocol (TIP) Series, No. 25.) Chapter 1—Effects of Domestic Violence on Substance Abuse Treatment. Available at www.ncbi.nlm.nih.gov/books/NBK64441, accessed June 12, 2017 .

44.

Cavanaugh

, Hansen

, Sullivan

: HIV sexual risk behaviour among low-income women experiencing IPV: The role of posttraumatic stress disorder. AIDS Behav, 2010; 14:318–327.

45.

Cohen

, Cook

, Grey

, et al.: Medically eligible women who do not use HAART: The importance of abuse, drug use, and race. Am J Public Health, 2004; 94:1147–1151.

46.

Lichtenstein

: Domestic violence in barriers to health care for HIV-positive women. AIDS Patient Care STDS, 2006; 20:122–132.

47.

Shannon

, Rusch

, Shoveller

, et al.: Mapping violence and policing as an environmental-structural barrier to health service and syringe availability among substance-using women in street-level work. Int J Drug Policy, 2008; 19:140–147.

48.

Torchalla

, Nosen

, Rostam

, et al.: Integrated treatment programs for individuals with concurrent substance use disorders and trauma experiences: A systematic review and meta-analysis. J Subst Abuse Treat, 2012; 42:65–77.

49.

Meade

, Drabkin

, Hansen

, et al.: Reductions in alcohol and cocaine use following a group coping intervention for HIV-positive adults with childhood sexual abuse histories. Addiction, 2010; 105:1942–1951.

50.

Ironson

, O'Cleirigh

, Leserman

, et al.: Gender-specific effects of an augmented written emotional disclosure intervention on posttraumatic, depressive, and HIV-disease-related outcomes: A randomized, controlled trial. J Consult Clin Psychol, 2013; 81:284–298.

51.

Green

, Kershaw

, Lin

, et al.: Patterns of drug use and abuse among aging adults with and without HIV: A latent class analysis of a US Veteran cohort. Drug Alcohol Depend, 2010; 110:208–220.

52.

Kraemer

, McGinnis

, Skanderson

, et al.: Alcohol problems and health care services use in human immunodeficiency virus (HIV)-infected and HIV-uninfected veterans. Med Care, 2006; 44(8 Suppl 2):S44–S51.

53.

Finneran

, Stephenson

: Intimate partner violence among men who have sex with men: A systematic review. Trauma Violence Abuse, 2013; 14:168–185.

54.

Buller

, Devries

, Howard

, et al.: Associations between intimate partner violence and health among men who have sex with men: A systematic review and meta-analysis. PLoS Med, 2014; 11:e1001609.

55.

Siemieniuk

, Miller

, Woodman

, et al.: Prevalence, clinical associations, and impact of intimate partner violence among HIV-infected gay and bisexual men: A population-based study. HIV Med, 2013; 14:293–302.

56.

Remis

, Liu

: HIV/AIDS in Ontario: Preliminary report 2011. Available at: www.ohemu.utoronto.ca/doc/PHERO2011_report_preliminary.pdf, accessed June 11, 2017 .

57.

Ross

, Vigod

, Wishart

, et al.: Barriers and facilitators to primary care for people with mental health and/or substance use issues: A qualitative study. BMC Fam Pract, 2015; 16:135.

58.

Bellamy CD

H F

, lanagan

, Costa

, et al.: Barriers and facilitators of healthcare for people with mental illness: Why integrated patient centered healthcare is necessary. Issues Ment Health Nurs, 2016; 37:421–428.

59.

Ontario Community HIV and AIDS Reporting Tool (OCHART). View from the Front Lines, (2015): Annual summary & analysis of data provided by community-based HIV/AIDS services in Ontario. Toronto, ON: AIDS and Hepatitis C Programs, Ontario Ministry of Health and Long-Term Care and the Public Health Agency of Canada, Ontario Region. 2015. Available at www.ochart.ca/OCHARTPortal/Content/Resources/VFTFL-en.pdf, accessed June 25, 2017 .

60.

Whetten

, Reif

, Whetten

, Murphy-McMillan

: Trauma, mental health, distrust, and stigma among HIV-positive persons: Implications for effective care. Psychosom Med, 2008; 70:531–538.

61.

Vigod

, Kurdyak

, Dennis

, et al.: Transitional interventions to reduce early psychiatric readmissions in adults: Systematic review. Br J Psychiatry, 2013; 202:187–194.

62.

Tjepkema

: Health care use among gay, lesbian and bisexual Canadians. Health Rep, 2008; 19:53–64.