Homelessness and adherence to antiretroviral therapy among a cohort of HIV-infected injection drug users

Low Non-structured Antiretroviral Therapy Interruptions in HIV-Infected Persons Who Inject Drugs Receiving Multidisciplinary Comprehensive HIV Care at an Outpatient Drug Abuse Treatment Center

Continuous HIV treatment is necessary to ensure successful combined antiretroviral therapy (cART). The aim of this study was to evaluate the incidence of patient-initiated non-structured treatment interruptions in HIV-infected persons who inject drugs and who received a multidisciplinary comprehensive program, including medical HIV care, drug-dependence treatment and psychosocial support, at a drug outpatient addiction center. Non-structured treatment interruptions were defined as ≥30 consecutive days off cART without medical indication. During a median follow-up of 53.8 months, 37/132 (28 %) patients experienced the first non-structured treatment interruptions. The cumulative probability of cART interruption at 5 years was 31.2 % (95 % CI 22.4-40.0). Current drug use injection ≥1/day (HR 14.77; 95 % CI 5.90-36.96) and cART naive patients (HR 0.35, 95 % CI 0.14-0.93) were predictive factors for non-structured treatment interruptions. HIV care provided at a drug addiction center is a useful strategy to sustain continuous cART, however, drug abstinence is essential for the long-term maintenance of cART.

The population impact of eliminating homelessness on HIV viral suppression among people who use drugs

OBJECTIVE

We sought to estimate the change in viral suppression prevalence if homelessness were eliminated from a population of HIV-infected people who use drugs.

DESIGN

Community-recruited prospective cohort of HIV-infected people who use drugs in Vancouver, Canada. Behavioural information was collected at baseline and linked to a province-wide HIV/AIDS treatment database. The primary outcome was viral suppression (<50 copies/ml) measured during subsequent routine clinical care.

METHODS

We employed an imputation-based marginal modelling approach. First, we used modified Poisson regression to estimate the relationship between homelessness and viral suppression (adjusting for sociodemographics, substance use, addiction treatment, and other confounders). Then, we imputed an outcome probability for each individual while manipulating the exposure (homelessness). Population viral suppression prevalence under realized and 'housed' scenarios were obtained by averaging these probabilities across the study population. Bootstrapping was conducted to calculate 95% confidence limits.

RESULTS

Of 706 individuals interviewed between January 2005 and December 2013, the majority were men (66.0%), of white race/ethnicity (55.1%), and had a history of injection drug use (93.6%). At first study visit, 223 (31.6%) reported recent homelessness, and 37.8% were subsequently identified as virally suppressed. Adjusted marginal models estimated a 15.1% relative increase [95% confidence interval (CI) 9.0-21.7%) in viral suppression in the entire population - to 43.5% (95% CI 39.4-48.2%) - if all homeless individuals were housed. Among those homeless, eliminating this exposure would increase viral suppression from 22.0 to 40.1% (95% CI 35.1-46.1%), an 82.3% relative increase.

CONCLUSION

Interventions to house homeless, HIV-positive individuals who use drugs could significantly increase population viral suppression. Such interventions should be implemented as a part of renewed HIV/AIDS prevention and treatment efforts.

Homelessness, HIV, and Incomplete Viral Suppression

BACKGROUND

The importance of HIV viral suppression is widely known, however few studies have examined the effects of homelessness on HIV viral suppression.

METHODS

The study included HIV-seropositive patients in a health care for the homeless program (HCH). Electronic medical record data for 138 patients were analyzed to compare demographic characteristics, health characteristics, and utilization by housing status. For the 95 individuals with available HIV viral loads, multivariable logistic analysis was performed to examine factors associated with incomplete viral suppression.

RESULTS

The adjusted odds ratio of incomplete HIV viral load suppression was 3.84 times higher in homeless compared with housed (95% CI 1.36- 10.36) individuals. Illicit drug use and combined antiretrovirals (cART) were associated with HIV viral suppression.

CONCLUSIONS

Homelessness predicted incomplete HIV viral suppression. Stable housing may improve viral suppression and access to cART. Drug use was associated with viral suppression, likely because of patient engagement with on-site addiction services.

Housing Status, Medical Care, and Health Outcomes Among People Living With HIV/AIDS: A Systematic Review

BACKGROUND

Accumulating evidence suggests responses to HIV that combine individual-level interventions with those that address structural or contextual factors that influence risks and health outcomes of infection. Housing is such a factor. Housing occupies a strategic position as an intermediate structural factor, linking "upstream" economic, social, and cultural determinants to the more immediate physical and social environments in which everyday life is lived. The importance of housing status for HIV prevention and care has been recognized, but much of this attention has focused on homeless individuals as a special risk group. Analyses have less often addressed community housing availability and conditions as factors influencing population health or unstable, inadequate, or unaffordable housing as a situation or temporary state. A focus on individual-level characteristics associated with literal homelessness glosses over social, economic, and policy drivers operating largely outside any specific individual's control that affect housing and residential environments and the health resources or risk exposures such contexts provide.

OBJECTIVES

We examined the available empirical evidence on the association between housing status (broadly defined), medical care, and health outcomes among people with HIV and analyzed results to inform future research, program development, and policy implementation.

SEARCH METHODS

We searched 8 electronic health and social science databases from January 1, 1996, through March 31, 2014, using search terms related to housing, dwelling, and living arrangements and HIV and AIDS. We contacted experts for additional literature.

SELECTION CRITERIA

We selected articles if they were quantitative analyses published in English, French, or Spanish that included at least 1 measure of housing status as an independent variable and at least 1 health status, health care, treatment adherence, or risk behavior outcome among people with HIV in high-income countries. We defined housing status to include consideration of material or social dimensions of housing adequacy, stability, and security of tenure.

DATA COLLECTION AND ANALYSIS

Two independent reviewers performed data extraction and quality appraisal. We used the Cochrane Risk of Bias Tool for randomized controlled trials and a modified version of the Newcastle Ottawa Quality Appraisal Tool for nonintervention studies. In our quality appraisal, we focused on issues of quality for observational studies: appropriate methods for determining exposure and measuring outcomes and methods to control confounding.

RESULTS

Searches yielded 5528 references from which we included 152 studies, representing 139,757 HIV-positive participants. Most studies were conducted in the United States and Canada. Studies examined access and utilization of HIV medical care, adherence to antiretroviral medications, HIV clinical outcomes, other health outcomes, emergency department and inpatient utilization, and sex and drug risk behaviors. With rare exceptions, across studies in all domains, worse housing status was independently associated with worse outcomes, controlling for a range of individual patient and care system characteristics.

CONCLUSIONS

Lack of stable, secure, adequate housing is a significant barrier to consistent and appropriate HIV medical care, access and adherence to antiretroviral medications, sustained viral suppression, and risk of forward transmission. Studies that examined the history of homelessness or problematic housing years before outcome assessment were least likely to find negative outcomes, homelessness being a potentially modifiable contextual factor. Randomized controlled trials and observational studies indicate an independent effect of housing assistance on improved outcomes for formerly homeless or inadequately housed people with HIV. Housing challenges result from complex interactions between individual vulnerabilities and broader economic, political, and legal structural determinants of health. The broad structural processes sustaining social exclusion and inequality seem beyond the immediate reach of HIV interventions, but changing housing and residential environments is both possible and promising.

IAPAC Guidelines for Optimizing the HIV Care Continuum for Adults and Adolescents

BACKGROUND

An estimated 50% of people living with HIV (PLHIV) globally are unaware of their status. Among those who know their HIV status, many do not receive antiretroviral therapy (ART) in a timely manner, fail to remain engaged in care, or do not achieve sustained viral suppression. Barriers across the HIV care continuum prevent PLHIV from achieving the therapeutic and preventive effects of ART.

METHODS

A systematic literature search was conducted, and 6132 articles, including randomized controlled trials, observational studies with or without comparators, cross-sectional studies, and descriptive documents, met the inclusion criteria. Of these, 1047 articles were used to generate 36 recommendations to optimize the HIV care continuum for adults and adolescents.

RECOMMENDATIONS

Recommendations are provided for interventions to optimize the HIV care environment; increase HIV testing and linkage to care, treatment coverage, retention in care, and viral suppression; and monitor the HIV care continuum.

Effect of HIV Housing Services on Engagement in Care and Treatment, New York City, 2011

The federal Housing Opportunities for Persons with AIDS (HOPWA) program addresses housing needs of low-income persons living with HIV/AIDS (PLWHA). The New York City (NYC) Department of Health and Mental Hygiene oversees 22 HOPWA contracts for over 2,400 clients, and manages the NYC HIV Registry. HOPWA clients (N = 1,357) were matched to a random 20 % sample of other PLWHA (N = 13,489). Groups were compared on HIV care retention, viral suppression, and rebound. HOPWA clients were, on average, 3 years younger and more likely to be concurrently diagnosed with HIV and AIDS. While HOPWA clients were more likely to be retained in care (94 vs. 82 %; mOR = 2.97, 95 % CI 2.35-3.74), they were no more likely to achieve suppression (84 vs. 86 %; mOR = 0.85, 95 % 0.70-1.03) and were more likely to rebound (11 vs. 7 %; mOR = 1.45; 95 % CI 1.10-1.91). HIV care retention does not fully translate to virologic suppression in this low-income service population.

Comparison of behavioral characteristics of dogs in the United States and Japan

This study examined the difference in dog owning between Japan and the United States, and the effect of these differences on dogs' behavioral characteristics. Behavioral evaluations of privately-owned dogs were obtained by using online questionnaire. We compared background and demographic information from the two countries and analyzed the effects of these differences on behavioral characteristics in dogs. The results indicated that there was a bias in the dog breeds kept in Japan compared to the United States and that Japanese dogs' body weight was lower than the US dogs. The main source of dog acquisition was pet stores in Japan and breeders and/or shelters in the United States. Multiple linear regression analysis found that Japanese dogs showed more aggression to household members and higher energy, restlessness and fear of non-social stimuli than US dogs, while US dogs showed more fear of unfamiliar persons, separation-related behavior and excitability. US dogs also showed higher levels of trainability and attachment to owners. The lower dog's body weight was, the higher the behavioral scores except for trainability were. When dogs that were obtained under 3 months of age were analyzed, the younger the dogs were when their owners obtained them, the higher the scores on some behavioral problem factors were. The higher rates of problem behaviors among Japanese dogs compared with US dogs suggest that the preference for small breed dogs and poor early development environment influenced the behavioral characteristics of dogs.

Dose-response relationship between methadone dose and adherence to antiretroviral therapy among HIV-positive people who use illicit opioids

BACKGROUND AND AIMS

For HIV-positive individuals who use illicit opioids, engagement in methadone maintenance therapy (MMT) can contribute to improved HIV treatment outcomes. However, to our knowledge, the role of methadone dosing in adherence to antiretroviral therapy (ART) has not yet been investigated. We sought to examine the relationship between methadone dose and ART adherence among a cohort of people who use illicit opioids.

DESIGN AND SETTING

We used data from the AIDS Care Cohort to Evaluate Access to Survival Services (ACCESS) study, an ongoing prospective observational cohort of HIV-positive people who use illicit drugs in Vancouver, Canada, linked confidentially to comprehensive HIV treatment data in a setting of universal no-cost medical care, including medications. We evaluated the longitudinal relationship between methadone dose and the likelihood of ≥ 95% adherence to ART among ART-exposed participants during periods of engagement in MMT.

PARTICIPANTS

Two hundred and ninety-seven ART-exposed individuals on MMT were recruited between December 2005 and May 2013 and followed for a median of 42.1 months.

MEASUREMENTS

We measured methadone dose at ≥ 100 versus < 100 mg/day and the likelihood of ≥ 95% adherence to ART.

FINDINGS

In adjusted generalized estimating equation (GEE) analyses, MMT dose ≥ 100 mg/day was associated independently with optimal adherence to ART [adjusted odds ratio (AOR) = 1.38; 95% confidence interval (CI) = 1.08-1.77). In a subanalysis, we observed a dose-response relationship between increasing MMT dose and ART adherence (AOR = 1.06 per 20 mg/day increase, 95% CI = 1.00-1.12).

CONCLUSION

Among HIV-positive individuals in methadone maintenance therapy, those receiving higher doses of methadone (≥ 100 mg/day) are more likely to achieve ≥ 95% adherence to antiretroviral therapy than those receiving lower doses.

Environmental Influences on HIV Medication Adherence: The Role of Neighborhood Disorder

OBJECTIVES

We hypothesized that highly disordered neighborhoods would expose residents to environmental pressures, leading to reduced antiretroviral (ARV) medication adherence.

METHODS

Using targeted sampling, we enrolled 503 socioeconomically disadvantaged HIV-positive substance users in urban South Florida between 2010 and 2012. Participants completed a 1-time standardized interview that took approximately 1 hour. We tested a multiple mediation model to examine the direct and indirect effects of neighborhood disorder on diversion-related nonadherence to ARVs; risky social networks and housing instability were examined as mediators of the disordered neighborhood environment.

RESULTS

The total indirect effect in the model was statistically significant (P = .001), and the proportion of the total effect mediated was 53%. The model indicated substantial influence of neighborhood disorder on nonadherence to ARVs, operating through recent homelessness and diverter network size.

CONCLUSIONS

Long-term improvements in diversion-related ARV adherence will require initiatives to reduce demand for illicit ARV medications, as well as measures to reduce patient vulnerability to diversion, including increased resources for accessible housing, intensive treatment, and support services.

Medication adherence challenges among patients experiencing homelessness in a behavioral health clinic

BACKGROUND

Behavioral health medication nonadherence is associated with poor health outcomes and increased healthcare costs. Little is known about reasons for nonadherence with behavioral health medications among homeless people.

OBJECTIVES

To identify reasons for medication nonadherence including the sociodemographic, health-related factors, and behavioral health conditions associated with medication nonadherence among behavioral health patients served by a Health Care for the Homeless center (HCH) in Virginia.

METHODS

The study sample was selected from an existing database that included sociodemographic, health-related information, and medication-related problems identified during a pharmacist-provided medication review conducted during October 2008-September 2009. Patients experiencing or at risk of homelessness who were ≥18 years old with at least one behavioral health condition who had a medication review were eligible for the study. A qualitative content analysis of the pharmacist documentation describing the patient's reason(s) for medication nonadherence was conducted. The Behavioral Model for Vulnerable Populations was the theoretical framework. The outcome variable was self-reported medication nonadherence. Descriptive and multivariate (logistic regression) statistics were used.

RESULTS

A total of 426 individuals met study criteria. The mean age was 44.7 ± 10.2 years. Most patients were African-American (60.5%) and female (51.6%). The content analysis identified patient-related factors (74.8%), therapy-related factors (11.8%), and social or economic factors (8.8%) as the most common reasons for patients' medication nonadherence. Patients with post-traumatic stress disorder (PTSD) (adjusted odds ratio: 0.4; 95% CI: 0.19-0.87) were less likely to have a medication adherence problem identified during the medication review.

CONCLUSIONS

The content analysis identified patient-related factors as the most common reason for nonadherence with behavioral health medications. In the quantitative analysis, patients with a PTSD diagnosis were less likely to have nonadherence identified which may be related to their reluctance to self-report nonadherence and their diagnosis, which warrants further study.

Factors linked to transitions in adherence to antiretroviral therapy among HIV-infected illicit drug users in a Canadian setting

HIV-positive people who use illicit drugs typically achieve lower levels of adherence to antiretroviral therapy and experience higher rates of sub-optimal HIV/AIDS treatment outcomes. Given the dearth of longitudinal research into ART adherence dynamics, we sought to identify factors associated with transitioning into and out of optimal adherence to ART in a longitudinal study of HIV-infected people who use illicit drugs (PWUD) in a setting of universal no-cost HIV/AIDS treatment. Using data from a prospective cohort of community-recruited HIV-positive illicit drug users confidentially linked to comprehensive HIV/AIDS treatment records, we estimated longitudinal factors associated with losing or gaining ≥95% adherence in the previous six months using two generalized linear mixed-effects models. Among 703 HIV-infected ART-exposed PWUD, becoming non-adherent was associated with periods of homelessness (adjusted odds ratio [AOR] = 2.52, 95% confidence interval [95% CI]: 1.56-4.07), active injection drug use (AOR = 1.25, 95% CI: 1.01-1.56) and incarceration (AOR = 1.54, 95% CI: 1.10-2.17). Periods of sex work (AOR = 0.51, 95% CI: 0.34-0.75) and injection drug use (AOR = 0.62, 95% CI: 0.50-0.77) were barriers to becoming optimally adherent. Methadone maintenance therapy was associated with becoming optimally adherent (AOR = 1.87, 95% CI: 1.50-2.33) and was protective against becoming non-adherent (AOR = 0.52, 95% CI: 0.41-0.65). In conclusion, we identified several behavioural, social and structural factors that shape adherence patterns among PWUD. Our findings highlight the need to consider these contextual factors in interventions that support the effective delivery of ART to this population.

Tailored combination prevention packages and PrEP for young key populations

INTRODUCTION

Young key populations, defined in this article as men who have sex with men, transgender persons, people who sell sex and people who inject drugs, are at particularly high risk for HIV. Due to the often marginalized and sometimes criminalized status of young people who identify as members of key populations, there is a need for HIV prevention packages that account for the unique and challenging circumstances they face. Pre-exposure prophylaxis (PrEP) is likely to become an important element of combination prevention for many young key populations.

OBJECTIVE

In this paper, we discuss important challenges to HIV prevention among young key populations, identify key components of a tailored combination prevention package for this population and examine the role of PrEP in these prevention packages.

METHODS

We conducted a comprehensive review of the evidence to date on prevention strategies, challenges to prevention and combination prevention packages for young key populations. We focused specifically on the role of PrEP in these prevention packages and on young people under the age of 24, and 18 in particular.

RESULTS AND DISCUSSION

Combination prevention packages that include effective, acceptable and scalable behavioural, structural and biologic interventions are needed for all key populations to prevent new HIV infections. Interventions in these packages should meaningfully involve beneficiaries in the design and implementation of the intervention, and take into account the context in which the intervention is being delivered to thoughtfully address issues of stigma and discrimination. These interventions will likely be most effective if implemented in conjunction with strategies to facilitate an enabling environment, including increasing access to HIV testing and health services for PrEP and other prevention strategies, decriminalizing key populations' practices, increasing access to prevention and care, reducing stigma and discrimination, and fostering community empowerment. PrEP could offer a highly effective, time-limited primary prevention for young key populations if it is implemented in combination with other programs to increase access to health services and encourage the reliable use of PrEP while at risk of HIV exposure.

CONCLUSIONS

Reductions in HIV incidence will only be achieved through the implementation of combinations of interventions that include biomedical and behavioural interventions, as well as components that address social, economic and other structural factors that influence HIV prevention and transmission.

High-intensity cannabis use and adherence to antiretroviral therapy among people who use illicit drugs in a Canadian setting

Cannabis is increasingly prescribed clinically and utilized by people living with HIV/AIDS (PLWHA) to address symptoms of HIV disease and to manage side effects of antiretroviral therapy (ART). In light of concerns about the possibly deleterious effect of psychoactive drug use on adherence to ART, we sought to determine the relationship between high-intensity cannabis use and adherence to ART among a community-recruited cohort of HIV-positive illicit drug users. We used data from the ACCESS study, an ongoing prospective cohort study of HIV-seropositive illicit drug users linked to comprehensive ART dispensation records in a setting of universal no-cost HIV care. We estimated the relationship between at least daily cannabis use in the last 6 months, measured longitudinally, and the likelihood of optimal adherence to ART during the same period, using a multivariate linear mixed-effects model accounting for relevant socio-demographic, behavioral, clinical and structural factors. From May 2005 to May 2012, 523 HIV-positive illicit drug users were recruited and contributed 2,430 interviews. At baseline, 121 (23.1 %) participants reported at least daily cannabis use. In bivariate and multivariate analyses we did not observe an association between using cannabis at least daily and optimal adherence to prescribed HAART (Adjusted Odds Ratio = 1.12, 95 % Confidence Interval [95 % CI]: 0.76-1.64, p value = 0.555.) High-intensity cannabis use was not associated with adherence to ART. These findings suggest cannabis may be utilized by PLWHA for medicinal and recreational purposes without compromising effective adherence to ART.

Barriers to Prescription Medication Adherence Among Homeless and Vulnerably Housed Adults in Three Canadian Cities

Objectives: Medication adherence is an important determinant of successful medical treatment. Marginalized populations, such as homeless and vulnerably housed individuals, may face substantial barriers to medication adherence. This study aimed to determine the prevalence of, reasons for, and factors associated with medication nonadherence among homeless and vulnerably housed individuals. Additionally, we examined the association between medication nonadherence and subsequent emergency department utilization during a 1-year follow-up period. Methods: Data were collected as part of the Health and Housing in Transition study, a prospective cohort study tracking the health and housing status of 595 homeless and 596 vulnerably housed individuals in 3 Canadian cities. Logistic regression was used to identify factors associated with medication nonadherence, as well as the association between medication nonadherence at baseline and subsequent emergency department utilization. Results: Among 716 participants who had been prescribed a medication, 189 (26%) reported nonadherence. Being ≥40 years old was associated with decreased likelihood of nonadherence (adjusted odds ratio [AOR] = 0.59; 95% confidence interval [CI] = 0.41-0.84), as was having a primary care provider (AOR = 0.49; 95% CI = 0.34-0.71). Having a positive screen on the AUDIT (Alcohol Use Disorders Identification Test; an indication of harmful or hazardous drinking) was associated with increased likelihood of nonadherence (AOR = 1.86; 95% CI = 1.31-2.63). Common reasons for nonadherence included side effects, cost, and lack of access to a physician. Self-reported nonadherence at baseline was significantly associated with frequent emergency department use (≥3 visits) over the follow-up period at the bivariate level (OR = 1.55; 95% CI = 1.02-2.35) but was not significant in a multivariate model (AOR = 1.49; 95% CI = 0.96-2.32). Conclusion: Homeless and vulnerably housed individuals face significant barriers to medication adherence. Health care providers serving this population should be particularly attentive to nonadherence among younger patients and those with harmful or hazardous drinking patterns.

Medication adherence challenges among HIV positive substance abusers: the role of food and housing insecurity

This study examines the prevalence of food/housing insecurity and its association with psychological, behavioral, and environmental factors impacting antiretroviral (ARV) medication adherence and diversion among substance using HIV+ patients in South Florida. Five hundred and three HIV+ substance abusers were recruited through targeted sampling. Participants completed a standardized instrument assessing demographics, mental health status, sex risk behaviors, HIV diagnosis, treatment history and access, ARV adherence and diversion, and attitudes toward health-care providers. Chi-square and t-tests were used to examine differences by food/housing status and a multivariate linear regression model examined food/housing insecurity and its associations to ARV adherence. Food/housing insecurity was reported by 43.3% of the sample and was associated with higher likelihood of severe psychological distress and substance dependence. Nearly 60% reported recent ARV diversion; only 47.2% achieved 95% medication adherence over one week. Food/housing insecure participants had deficits in their HIV care, including less time in consistent care, lower access to medical care, and less favorable attitudes toward care providers. Multivariate linear regression showed food/housing insecurity demonstrated significant main effects on adherence, including lower past week adherence. Medication diversion was also associated with reduced adherence. Our findings suggest that food/housing insecurity operates as a significant driver of ARV non-adherence and diversion in this population. In the pursuit of better long-term health outcomes for vulnerable HIV+ individuals, it is essential for providers to understand the role of food and housing insecurity as a stressor that negatively impacts ARV adherence and treatment access, while also significantly contributing to higher levels of distress and substance dependence.

A review of the role of food insecurity in adherence to care and treatment among adult and pediatric populations living with HIV and AIDS

Adherence to antiretroviral therapy (ART) is critical for reducing HIV/AIDS morbidity and mortality. Food insecurity (FI) is emerging as an important barrier to adherence to care and treatment recommendations for people living with HIV (PLHIV), but this relationship has not been comprehensively examined. Therefore, we reviewed the literature to explore how FI may impact ART adherence, retention in medical care, and adherence to health care recommendations among PLHIV. We found data to support FI as a critical barrier to adherence to ART and to other health care recommendations among HIV-infected adults, HIV-infected pregnant women and their HIV-exposed infants, and child and adolescent populations of PLHIV. Associations between FI and ART non-adherence were seen in qualitative and quantitative studies. We identified a number of mechanisms to explain how food insecurity and ART non-adherence may be causally linked, including the exacerbation of hunger or ART side effects in the absence of adequate food and competing resource demands. Interventions that address FI may improve adherence to care and treatment recommendations for PLHIV.

HIV prevention in clinical care settings: 2014 recommendations of the International Antiviral Society-USA Panel

IMPORTANCE

Emerging data warrant the integration of biomedical and behavioral recommendations for human immunodeficiency virus (HIV) prevention in clinical care settings.

OBJECTIVE

To provide current recommendations for the prevention of HIV infection in adults and adolescents for integration in clinical care settings.

DATA SOURCES, STUDY SELECTION, AND DATA SYNTHESIS

Data published or presented as abstracts at scientific conferences (past 17 years) were systematically searched and reviewed by the International Antiviral (formerly AIDS) Society-USA HIV Prevention Recommendations Panel. Panel members supplied additional relevant publications, reviewed available data, and formed recommendations by full-panel consensus.

RESULTS

Testing for HIV is recommended at least once for all adults and adolescents, with repeated testing for those at increased risk of acquiring HIV. Clinicians should be alert to the possibility of acute HIV infection and promptly pursue diagnostic testing if suspected. At diagnosis of HIV, all individuals should be linked to care for timely initiation of antiretroviral therapy (ART). Support for adherence and retention in care, individualized risk assessment and counseling, assistance with partner notification, and periodic screening for common sexually transmitted infections (STIs) is recommended for HIV-infected individuals as part of care. In HIV-uninfected patients, those persons at high risk of HIV infection should be prioritized for delivery of interventions such as preexposure prophylaxis and individualized counseling on risk reduction. Daily emtricitabine/tenofovir disoproxil fumarate is recommended as preexposure prophylaxis for persons at high risk for HIV based on background incidence or recent diagnosis of incident STIs, use of injection drugs or shared needles, or recent use of nonoccupational postexposure prophylaxis; ongoing use of preexposure prophylaxis should be guided by regular risk assessment. For persons who inject drugs, harm reduction services should be provided (needle and syringe exchange programs, supervised injection, and available medically assisted therapies, including opioid agonists and antagonists); low-threshold detoxification and drug cessation programs should be made available. Postexposure prophylaxis is recommended for all persons who have sustained a mucosal or parenteral exposure to HIV from a known infected source and should be initiated as soon as possible.

CONCLUSIONS AND RELEVANCE

Data support the integration of biomedical and behavioral approaches for prevention of HIV infection in clinical care settings. A concerted effort to implement combination strategies for HIV prevention is needed to realize the goal of an AIDS-free generation.

Opioid analgesic misuse is associated with incomplete antiretroviral adherence in a cohort of HIV-infected indigent adults in San Francisco

There is little or no data examining the association between either pain or the use or misuse of opioid analgesic with adherence to antiretroviral medications (ARVs) among HIV-infected adults. We interviewed a community-based cohort of HIV-infected indigent adults prescribed antiretroviral medications (ARVs) quarterly to examine the association between (1) pain, (2) receipt of opioid analgesics, and (3) opioid analgesic misuse with self-reported ARV adherence. Of 281 participants, most (82.5 %) reported severe or moderate pain, half (52.4 %) received a prescription for opioids, and one quarter (24.6 %) misused opioid analgesics. Most (71.9 %) reported >90 % ARV adherence. In a GEE model, neither pain (unadjusted OR 1.14, CI 0.90–1.45) nor prescription of opioid analgesics (unadjusted OR 1.11, CI 0.84–1.49) were significantly associated with ARV adherence. Misuse of opioid analgesics was associated with incomplete adherence (AOR 1.42, CI 1.09–1.86). Individuals who misuse opioid analgesics, like those who use illicit substances, may have difficulty adhering to medication regimens.

Correlates of drug use cessation among participants in the Canadian HIV-HCV Co-infection Cohort

BACKGROUND

Ongoing drug use remains a barrier to HIV and HCV treatment. We examined the occurrence and correlates of drug use cessation among HIV-HCV co-infected drug users participating in HIV care.

METHODS

Participants from the Canadian Co-infection Cohort reporting drug use (injecting drugs and/or smoking crack) with at least two follow-up visits were included (n=521 (43%), 1832 visits). Socio-demographics, behavioural, and health information were collected at each six-month visit. Associations with cessation (no drug use since last visit) were examined using non-linear mixed effects logistic regression models with random intercepts.

RESULTS

During follow-up, 361 (69%) participants ceased using drugs. Having a fixed address (aOR [adjusted odds ratio] 1.73, CI [95% confidence interval] 1.02-2.96) and smoking crack without injecting drugs (aOR 3.10, CI 2.05-4.71) were positively associated. Living alone (aOR 0.47, CI 0.35-0.63), current tobacco use (aOR 0.41, CI 0.26-0.64), hazardous alcohol drinking (aOR 0.67, CI 0.49-0.91), snorting drugs (aOR 0.52, CI 0.37-0.74), having a greater exposure to addiction programmes (aOR 0.88, CI 0.81-0.94), having been recruited in Quebec or Nova Scotia (aOR 0.41, CI 0.25-0.66), and British Columbia or Alberta (aOR 0.51, CI 0.32-0.82) were negatively associated. Various socio-demographic (age, education) and health-related (HIV duration, care adherence) factors were not associated.

CONCLUSION

Drug use cessation among HIV-HCV co-infected persons is relatively common in this cohort. Stable housing and supportive living situations seem to be important facilitators for drug use cessation in this population. Greater efforts should be made to retain patients in addiction treatment programmes.

Demographics, Health-Care Utilization, and Substance Use Profiles of Older Adults in Canada's Lowest Income Neighbourhood

BACKGROUND

This study aimed to determine the baseline demographics, health status, and drug use profiles of current and former substance-using older adults in Vancouver's Downtown Eastside.

METHODS

Data were derived from two U.S. National Institutes of Health-funded cohort studies of current and former illegal drug users in Vancouver's Downtown Eastside. We used logistic regression of cross-sectional data obtained between June and November 2008 to calculate odds ratios and identify factors that were more commonly associated with cohort members being older adults (greater than or equal to age 50).

RESULTS

214 subjects (25%) were greater than or equal to age 50 upon study enrollment. Females (Adjusted Odds Ratio [AOR]: 0.50; 95% CI: 0.34-0.75) and individuals who reported Aboriginal ancestry (AOR: 0.49; 95% CI: 0.33-0.72) were less likely to be in the older cohort. Individuals with higher income (AOR: 2.07; 95% CI: 1.16-3.68 per $1,000), and those with a regular place to stay were more likely to be in older cohort (AOR: 3.39; 95% CI: 1.90-6.06). Older participants accessed family physicians more frequently (OR: 1.47; 95% CI: 1.01 - 2.16) and were more likely to be actively taking (OR: 3.34; 95% CI 1.71-6.55) or have taken (OR 3.21; 95% CI 1.58-6.53) HIV antiretroviral therapy. There were no differences between groups in regard to injection drug use status or daily alcohol intake.

CONCLUSIONS

Older current and former illegal drug users in a major inner city Canadian centre have different demographic, health-care, and drug utilization profiles. Further studies in this population are warranted.

Medication adherence part two: predictors of nonadherence and adherence

PURPOSE

This is the second of a three-part series on medication adherence in which the authors describe the continuum of adherence to nonadherence of medication usage.

DATA SOURCES

Research articles through MEDLINE and PubMed.

CONCLUSIONS

Understanding the magnitude and scope of the problem of medication nonadherence is the first step in reaching better adherence rates (described in Part One of this series). The second step is to recognize the complexities of the reasons for medication adherence/nonadherence (described here). Reasons for nonadherence include beliefs related to the benefits of medication for physical and mental disorders, complexities of systems of health care and treatment plans, and lifestyle and demographic characteristics of patients. The final step is to evaluate each patient for medication adherence, tailoring the plan of care according to patient and system specific barriers (described in Part Three of this series).

IMPLICATIONS FOR PRACTICE

Nurse practitioners must recognize a critical element of thorough care is to assess medication adherence at each patient visit, countering patient and system barriers as indicated. Nurse practitioners also need to adjust assessment and prescribing practices according to the evidence for best practices to improve medication adherence.

HIV prevention for people who use substances: evidence-based strategies

Evidence-based strategies to guide HIV prevention for people who use substances can be grouped into approaches that lower infectiousness among substance users living with HIV and those that prevent HIV acquisition among those who are uninfected. Dramatic successes in HIV prevention involving access to antiretroviral therapy (ART), opioid substitution therapies, and needle and syringe exchange programs have reduced both prevalence and incidence in the United States for people who use injection drugs, and modeling studies suggest that scale-up of these approaches will have a parallel impact worldwide. Medical HIV-prevention strategies that reduce infectiousness ("treatment as prevention" or early ART initiation) and that block HIV acquisition (pre-exposure prophylaxis, post-exposure prophylaxis) can constitute key elements of novel combination HIV-prevention approaches to the goals of reducing infectiousness and reducing acquisition of HIV among people who use substances. For individuals who use substances but do not inject, drug dependence treatments as HIV prevention have a meager evidence-base, with most consistent findings being reduction of sexual transmission behaviors that correspond with reductions in substance use, though not with prevention of HIV transmission. This approach may have value, however, when working with groups of substance users who face high rates of HIV prevalence and incidence. Some evidence exists to support HIV prevention interventions that target reduction of sexual risk behaviors in the setting of active stimulant use.

Lost or just not following up: public health effort to re-engage HIV-infected persons lost to follow-up into HIV medical care

OBJECTIVE

Locate persons living with HIV (PLWH) presumed lost to follow-up (LTFU), and assist them with partner services and linkage to HIV-related care.

DESIGN

Locate and facilitate re-engagement in care for PLWH-LTFU in New York City (NYC), with longitudinal follow-up using HIV surveillance registry.

SETTINGS

HIV care facilities and communities in NYC.

PATIENTS

PLWH, reported in the NYC HIV surveillance registry, who had a NYC care provider and residential address at last report in the registry. Presumed-LTFU was defined as having no CD4+ or viral load during the most recent 9 months during the study period July 2008-December 2010.

INTERVENTION

Case-workers conducted public health investigation to locate PLWH presumed-LTFU and offered them assistance with partner and linkage-to-care services.

MAIN OUTCOME MEASURES

Results of partner and linkage-to-care services, and reasons for LTFU.

RESULTS

From July 2008 to December 2010, 797 PLWH presumed-LTFU were prioritized for investigation; 14% were never located. Of the 689 located, 33% were current to care, 5% had moved or were incarcerated, 2% had died, and 59% (409) were verified to be LTFU. Once located, 77% (315/409) accepted clinic appointments, and 57% (232/409) returned to care. Among the 161 who provided reasons for LTFU, the most commonly reported was 'felt well' (41%).

CONCLUSIONS

Health department case-workers helped more than half PLWH-LTFU re-engage in HIV medical care. HIV prevention strategies must include efforts to re-engage PLWH-LTFU in care, for treatment consideration under current treatment guidelines to improve their clinical status and decrease transmission risk.

The effect of history of injection drug use and alcoholism on HIV disease progression

The effectiveness of highly active antiretroviral therapy (HAART) in preventing disease progression can be negatively influenced by the high prevalence of substance use among patients. Here, we quantify the effect of history of injection drug use and alcoholism on virologic and immunologic response to HAART. Clinical and survey data, collected at the start of HAART and at the interview date, were based on the study Longitudinal Investigations into Supportive and Ancillary Health Services (LISA) in British Columbia, Canada. Substance use was a three-level categorical variable, combining information on history of alcohol dependence and of injection drug use, defined as: no history of alcohol and injection drug use; history of alcohol or injection drug use; and history of both alcohol and injection drug use. Virologic response (pVL) was defined by ≥ 2 log10 copy/mL drop in a viral load. Immunologic response was defined as an increase in CD4 cell count percent of ≥ 100%. We used cumulative logit modeling for ordinal responses to address our objective. Of the 537 HIV-infected patients, 112 (21%) were characterized as having a history of both alcohol and injection drug use, 173 (32%) were nonadherent (<95%), 196 (36%) had a CD4⁺/pVL⁺ (Best) response, 180 (34%) a CD4⁺/pVL⁻ or a CD4⁻ /pVL⁺ (Incomplete) response, and 161 (30%) a CD4⁻ /pVL⁻ (Worst) response. For individuals with history of both alcohol and injection drug use, the estimated probability of non-adherence was 0.61, and (0.15, 0.25, 0.60) of Best, Incomplete and Worse responses, respectively. Screening and detection of substance dependence will identify individuals at high-risk for nonadherence and ideally prevent their HIV disease from progressing to advanced stages where HIV disease can become difficult to manage.

Seroadaptation in a sample of very poor Los Angeles area men who have sex with men

Data from 635 very poor men who have sex with men (MSM) were used to identify seroadaptation with 1,102 male partners reported between 2005 and 2007 in Los Angeles as part of the Sexual Acquisition and Transmission of HIV Cooperative Agreement Program. The mean age of the sample was 41.7 years; 53 % had experienced homelessness in the past year. Condoms were reported in 51 % of sexual events involving anal intercourse. HIV seroconcordance was reported in 41 % of sexual partnerships among HIV-positive participants. HIV-positive men were more likely to have oral-only or unprotected receptive anal intercourse and less likely to have unprotected insertive anal intercourse with HIV-negative or unknown partners compared to HIV-positive partners. Even in the face of poverty, HIV-positive MSM report mitigating risks of HIV-transmission though seroadaptation in the context of modest rates of condom use.

Learning to account for the social determinants of health affecting homeless persons

CONTEXT

Intersecting social determinants of health constrain access to care and treatment adherence among homeless populations. Because clinicians seldom receive training in the social determinants of health, they may be unprepared to account for or address these factors when developing treatment strategies for homeless individuals.

OBJECTIVES

This study explored: (i) clinicians' preparedness to provide care responsive to the social determinants of health in homeless populations, and (ii) the steps taken by clinicians to overcome shortcomings in their clinical training in regard to the social determinants of health.

METHODS

Qualitative interviews were conducted with doctors (n = 6) and nurses (n = 18) in six Canadian cities. Participants had at least 2 years of experience in providing care to homeless populations. Interview transcripts were analysed using methods of constant comparison.

RESULTS

Participants highlighted how, when first providing care to this population, they were unprepared to account for or address social determinants shaping the health of homeless persons. However, participants recognised the necessity of addressing these factors to situate care within the social and structural contexts of homelessness. Participants' accounts illustrated that experiential learning was critical to increasing capacity to provide care responsive to the social determinants of health. Experiential learning was a continuous process that involved: (i) engaging with homeless persons in multiple settings and contexts to inform treatment strategies; (ii) evaluating the efficacy of treatment strategies through continued observation and critical reflection, and (iii) adjusting clinical practice to reflect observations and new knowledge.

CONCLUSIONS

This study underscores the need for greater emphasis on the social determinants of health in medical education in the context of homelessness. These insights may help to inform the development and design of service-learning initiatives that integrate understandings of the social determinants of health, and thus potentially improve the readiness of clinicians to address the complex factors that shape the health of homeless populations.

Housing status and the health of people living with HIV/AIDS

Individuals who are homeless or living in marginal conditions have an elevated burden of infection with HIV. Existing research suggests the HIV/AIDS pandemic in resource-rich settings is increasingly concentrated among members of vulnerable and marginalized populations, including homeless/marginally-housed individuals, who have yet to benefit fully from recent advances in highly-active antiretroviral therapy (HAART). We reviewed the scientific evidence investigating the relationships between inferior housing and the health status, HAART access and adherence and HIV treatment outcomes of people living with HIV/AIDS (PLWHA.) Studies indicate being homeless/marginally-housed is common among PLWHA and associated with poorer levels of HAART access and sub-optimal treatment outcomes. Among homeless/marginally-housed PLWHA, determinants of poorer HAART access/adherence or treatment outcomes include depression, illicit drug use, and medication insurance status. Future research should consider possible social- and structural-level determinants of HAART access and HV treatment outcomes that have been shown to increase vulnerability to HIV infection among homeless/marginally-housed individuals. As evidence indicates homeless/marginally-housed PLWHA with adequate levels of adherence can benefit from HAART at similar rates to housed PLWHA, and given the individual and community benefits of expanding HAART use, interventions to identify HIV-seropositive homeless/marginally-housed individuals, and engage them in HIV care including comprehensive support for HAART adherence are urgently needed.

The potential uses of preexposure prophylaxis for HIV prevention among people who inject drugs

PURPOSE OF REVIEW

Oral preexposure prophylaxis (PrEP) has shown HIV preventive efficacy for several key populations at risk for HIV infection including MSM and heterosexual men and women in HIV serodiscordant relationships. An efficacy trial of daily oral tenofovir among people who inject drugs (IDU) is underway in Thailand.

RECENT FINDINGS

Although efficacy data is pending, there is emerging biological and public health plausibility data suggesting the utility of PrEP as an effective component of combination HIV prevention for IDU. Drawing from studies characterizing adherence to antiretroviral therapy for IDU, there are a range of scientific and operational considerations for the potential use of PrEP for IDU. We review here the available literature on the potential use of PrEP for IDU, barriers to uptake and adherence, and potential implementation science questions, which could address, and potently increase, the effectiveness of this intervention.

SUMMARY

IDU remain the most underserved population in the HIV response worldwide, and have a marked gap in prevention services, making PrEP a potentially promising addition to the prevention toolkit for people who use drugs and, for those already living with HIV infection, for their spouses and other sexual partners.

Service priorities and unmet service needs among people living with HIV/AIDS: results from a nationwide interview of HIV/AIDS housing organizations

Housing for people living with HIV/AIDS (PLWHA) has been linked to a number of positive physical and mental health outcomes, in addition to decreased sexual and drug-related risk behavior. The current study identified service priorities for PLWHA, services provided by HIV/AIDS housing agencies, and unmet service needs for PLWHA through a nationwide telephone survey of HIV/AIDS housing agencies in the USA. Housing, alcohol/drug treatment, and mental health services were identified as the three highest priorities for PLWHA and assistance finding employment, dental care, vocational assistance, and mental health services were the top needs not being met. Differences by geographical region were also examined. Findings indicate that while housing affords PLWHA access to services, there are still areas (e.g., mental health services) where gaps in linkages to care exist.

Substance use predictors of poor medication adherence: the role of substance use coping among HIV-infected patients in opioid dependence treatment

Many HIV-infected injection drug users (IDUs) continue to use illicit substances despite being in substance use treatment. Substance use is associated with non-adherence to HIV medications; however underlying mechanisms regarding this relation are understudied. The current investigation examined the role of substance use coping in terms of the relation between substance use and HIV medication adherence. Participants were 121 HIV-infected IDUs (41 % female, M age = 47, SD = 7.1) in opioid dependence treatment. Participants completed self-report questionnaires, were administered clinical interviews and oral toxicology screens, and used a medication-event-monitoring-system cap to assess 2 week HIV medication adherence. The use of cocaine and multiple substances were significantly related to decreased medication adherence. Substance use coping mediated these associations. Findings highlight the importance of assessing, monitoring, and targeting ongoing substance use, and ways to increase positive coping for HIV-infected IDUs in substance use treatment to aid in HIV medication adherence.

Heterogeneity in outcomes of treated HIV-positive patients in Europe and North America: relation with patient and cohort characteristics

BACKGROUND

HIV cohort collaborations, which pool data from diverse patient cohorts, have provided key insights into outcomes of antiretroviral therapy (ART). However, the extent of, and reasons for, between-cohort heterogeneity in rates of AIDS and mortality are unclear.

METHODS

We obtained data on adult HIV-positive patients who started ART from 1998 without a previous AIDS diagnosis from 17 cohorts in North America and Europe. Patients were followed up from 1 month to 2 years after starting ART. We examined between-cohort heterogeneity in crude and adjusted (age, sex, HIV transmission risk, year, CD4 count and HIV-1 RNA at start of ART) rates of AIDS and mortality using random-effects meta-analysis and meta-regression.

RESULTS

During 61 520 person-years, 754/38 706 (1.9%) patients died and 1890 (4.9%) progressed to AIDS. Between-cohort variance in mortality rates was reduced from 0.84 to 0.24 (0.73 to 0.28 for AIDS rates) after adjustment for patient characteristics. Adjusted mortality rates were inversely associated with cohorts' estimated completeness of death ascertainment [excellent: 96-100%, good: 90-95%, average: 75-89%; mortality rate ratio 0.66 (95% confidence interval 0.46-0.94) per category]. Mortality rate ratios comparing Europe with North America were 0.42 (0.31-0.57) before and 0.47 (0.30-0.73) after adjusting for completeness of ascertainment.

CONCLUSIONS

Heterogeneity between settings in outcomes of HIV treatment has implications for collaborative analyses, policy and clinical care. Estimated mortality rates may require adjustment for completeness of ascertainment. Higher mortality rate in North American, compared with European, cohorts was not fully explained by completeness of ascertainment and may be because of the inclusion of more socially marginalized patients with higher mortality risk.

Correlates of antiretroviral utilization among hospitalized HIV-infected crack cocaine users

Despite the availability of antiretroviral therapy (ART), HIV-infected drug users, particularly crack cocaine users, continue to have high HIV-related morbidity and mortality. We conducted a cross-sectional analysis of the baseline data for hospitalized HIV-infected crack cocaine users recruited for Project HOPE (Hospital Visit Is an Opportunity for Prevention and Engagement with HIV-Positive Crack Users) in Atlanta and Miami who were eligible for ART (reported any lifetime use of ART or CD4 <350 cells/μl). Among 350 eligible participants, whose mean age was 44.9 years (SD 7.0), 49% were male, 90% were black, and 81% were heterosexual. The median CD4 count was 144 cells/μl, and 78 of 350 (22%) were taking ART. We conducted a multivariable logistic regression to examine individual, interpersonal, and structural factors as potential correlates of ART use. Reporting ≥2 visits to outpatient HIV care in the past 6 months (AOR 7.55, 95% CI 3.80-14.99), drug or alcohol treatment in the past 6 months (AOR 2.29, 95% CI 1.06-4.94), and study site being Miami (AOR 2.99, 95% CI 1.56-5.73) were associated with ART use. Current homelessness (AOR 0.41, 95% CI 0.20-0.84) and CD4 <200 cells/μl (AOR 0.29, 95% CI 0.15-0.55) were negatively associated with ART use. Among those taking ART, 60% had an HIV-1 viral load <400 copies/ml; this represented 9% of the eligible population. For HIV-infected crack cocaine users, structural factors may be as important as individual and interpersonal factors in facilitating ART utilization. Few HIV(+) crack cocaine users had viral suppression, but among those on ART, viral suppression was achievable.

HIV risk behavior and access to services: what predicts HIV testing among heterosexually active homeless men?

HIV is a serious epidemic among homeless persons, where rates of infection are estimated to be three times higher than in the general population. HIV testing is an effective tool for reducing HIV transmission and for combating poor HIV/AIDS health outcomes that disproportionately affect homeless persons, however, little is known about the HIV testing behavior of homeless men. This study examined the association between individual (HIV risk) and structural (service access) factors and past year HIV testing. Participants were a representative sample of 305 heterosexually active homeless men interviewed from meal programs in the Skid Row region of Los Angeles. Logistic regression examined the association between past year HIV testing and demographic characteristics, HIV risk behavior, and access to other services in the Skid Row area in the past 30 days. Despite high rates of past year HIV testing, study participants also reported high rates of HIV risk behavior, suggesting there is still significant unmet need for HIV prevention among homeless men. Having recently used medical/dental services in the Skid Row area (OR: 1.91; CI: 1.09, 3.35), and being a military veteran (OR: 2.10; CI: 1.01-4.37) were significantly associated with HIV testing service utilization. HIV testing was not associated with HIV risk behavior, but rather with access to services and veteran status, the latter of which prior research has linked to increased service access. We suggest that programs encouraging general medical service access may be important for disseminating HIV testing services to this high-risk, vulnerable population.

The relationship between medication-related problems and behavioural health condition among patients served by a health care for the homeless centre

Objectives

To evaluate the association between behavioural health conditions and the presence of a medication-related problem (MRP) and the association between the type of MRP and the presence of a dual diagnosis.

Methods

We used an existing database from a behavioural health clinic for homeless persons. Logistic regression was used to assess the relationship between the type of behavioural health condition and MRP presence, and whether the type of MRP varied with the presence of a dual diagnosis.

Key findings

A total of 426 patients were eligible. The majority were black (61%) and women (53%). Patients were 44.7 ± 10.2 years old, taking 3.4 ± 2.4 medications and had 2.3 ± 0.9 behavioural health conditions. The majority (53%) had a dual diagnosis, 44% had depression, 30% had a bipolar disorder, 26% had a personality disorder and 12% had an anxiety disorder. Bipolar [odds ratio (OR) 4.0, 95% confidence interval (CI) 1.8–8.9] and anxiety disorders (OR 3.1, CI 1.0–9.2) and a dual diagnosis (OR 2.1, CI 1.2–3.8) were independently associated with the presence of an MRP. Patients with a dual diagnosis were more likely to have ineffective drug therapy (OR 1.7, CI 1.1–2.8) and less likely to have an adverse effect (OR 0.5, CI 0.3–0.9).

Conclusions

Patients with bipolar or anxiety disorders and/or a dual diagnosis may benefit from a pharmacist intervention to address MRPs. Pharmacists can make recommendations to improve the effectiveness of patients' medication therapy and help to resolve adverse effects.

Improved adherence to modern antiretroviral therapy among HIV-infected injecting drug users

OBJECTIVES

Adherence to antiretroviral therapy (ART) among injecting drug users (IDUs) is often suboptimal, yet little is known about changes in patterns of adherence since the advent of highly active antiretroviral therapy in 1996. We sought to assess levels of optimal adherence to ART among IDUs in a setting of free and universal HIV care.

METHODS

Data were collected through a prospective cohort study of HIV-positive IDUs in Vancouver, British Columbia. We calculated the proportion of individuals achieving at least 95% adherence in the year following initiation of ART from 1996 to 2009.

RESULTS

Among 682 individuals who initiated ART, the median age was 37 years (interquartile range 31-44 years) and 248 participants (36.4%) were female. The proportion achieving at least 95% adherence increased over time, from 19.3% in 1996 to 65.9% in 2009 (Cochrane-Armitage test for trend: P < 0.001). In a logistic regression model examining factors associated with 95% adherence, initiation year was statistically significant (odds ratio 1.08; 95% confidence interval 1.03-1.13; P < 0.001 per year after 1996) after adjustment for a range of drug use variables and other potential confounders.

CONCLUSIONS

The proportion of IDUs achieving at least 95% adherence during the first year of ART has consistently increased over a 13-year period. Although improved tolerability and convenience of modern ART regimens probably explain these positive trends, by the end of the study period a substantial proportion of IDUs still had suboptimal adherence, demonstrating the need for additional adherence support strategies.

Homelessness as a structural barrier to effective antiretroviral therapy among HIV-seropositive illicit drug users in a Canadian setting

Despite the advent of effective antiretroviral therapy (ART), HIV-seropositive injection drug users (IDU) continue to suffer from elevated levels of morbidity and mortality. Evidence is needed to identify social- and structural-level barriers to effective ART. We investigated the impact of homelessness on plasma HIV RNA response among illicit drug users initiating ART in a setting with free and universal access to HIV care. We accessed data from a long-running prospective cohort of community-recruited IDU linked to comprehensive HIV clinical monitoring and ART dispensation records. Using Cox proportional hazards with recurrent events modeling, we estimated the independent effect of homelessness on time to plasma HIV viral load suppression. Between May 1996 and September 2009, 247 antiretroviral naïve individuals initiated ART and contributed 1755 person-years of follow-up. Among these individuals, the incidence density of plasma HIV RNA suppression less than 500 copies/mm(3) was 56.7 (95% confidence interval [CI]: 46.9-66.0) per 100 person-years. In unadjusted analyses, homelessness was strongly associated with lower rates suppression (hazard ratio = 0.56, 95% CI: 0.40-0.78, p = 0.001), however, after adjustment for adherence this association was no longer significant (adjusted hazard ratio = 0.79, 95% CI: 0.56-1.11, p = 0.177). Homelessness poses a significant structural barrier to effective HIV treatment. However, since this relationship appears to be mediated by lower levels of ART adherence, interventions to improve adherence among members of this vulnerable population are needed.

Difficulty accessing crack pipes and crack pipe sharing among people who use drugs in Vancouver, Canada

Background

Crack pipe sharing can increase health risks among people who use drugs, yet the reasons for sharing these pipes have not been well described. Therefore, we sought to identify the prevalence and correlates of crack pipe sharing among a community-recruited sample of people who use illicit drugs in Vancouver, a setting where crack pipes are provided at low or no cost.

Findings

Data for this study were derived from two prospective cohorts of people who use drugs: the Vancouver Injection Drug Users Study (VIDUS) and the AIDS Care Cohort to evaluate Exposure to Survival Services (ACCESS). Multivariate logistic regression was used to identify factors independently associated with crack pipe sharing. Among 503 crack users, 238 (47.3%) participants reported having shared a crack pipe in the previous six months. Having acquired a mouthpiece in the last six months (adjusted odds ratio [AOR] = 1.91; 95% confidence interval [CI]: 1.31 - 2.79) and difficulty finding new pipes (AOR = 2.19; 95%CI: 1.42 - 3.37) were positively associated with pipe sharing. Binge drug use (AOR = 1.39; 95%CI: 0.96 - 2.02) was marginally associated with sharing pipes.

Discussion

There was a high prevalence of crack pipe sharing in a setting where crack pipes are distributed at low or no cost. Difficulty accessing crack pipes was independently and positively associated with this behavior. These findings suggest that additional efforts are needed to discourage crack pipe sharing as well as increase access to crack pipes.