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  • For over a decade, a study in Vancouver monitored 947 HIV-positive people who used drugs
  • People experiencing homelessness were at least 41% less likely to receive HIV treatment
  • Researchers recommend integration of HIV treatment, substance use and housing services

When used as directed, HIV treatment (antiretroviral therapy; ART) usually reduces the amount of HIV in the blood. Over time, with continued adherence, HIV levels in the blood fall to very low levels, commonly called “undetectable.” This suppression of HIV has at least two main benefits. First, it allows the immune system to largely undo the damage caused by HIV, leading to a stronger immune system. As a result, researchers increasingly expect that many ART users will have near-normal life expectancy. Second, well-designed clinical trials have found that people on ART who achieve and maintain an undetectable viral load do not pass on the virus to their sexual partners.

However, not all people with HIV are able to achieve and maintain an undetectable viral load. Studies suggest that there are issues that affect people’s ability to initiate and adhere to ART. Some of these include the following: social marginalization, mistrust of the medical system, severe mental illness, addiction, and access to nutritious food and to stable housing.

In Vancouver

To better understand some of the care and HIV treatment issues faced by people who use drugs, a team of researchers at the British Columbia Centre on Substance Use and the University of British Columbia have been analysing data collected from a long-term study called ACCESS (AIDS Cohort to Evaluate Exposure to Survival Services). The latest analysis from ACCESS focused on people recruited between 2005 and 2019. All participants were adults with HIV who used drugs.

Upon study entry and at six-month intervals, participants completed questionnaires that collected data on socio-economic issues, substance use, access to healthcare and related concerns. The Vancouver researchers accessed databases at the B.C. Centre for Excellence in HIV/AIDS Drug Treatment Program to incorporate clinical care into each participant’s study profile. This would include the results of lab tests (particularly CD4+ cell count and viral load) and details about access to HIV treatment.

In reviewing data collected from the study, researchers were interested in participants’ progress through the stages of HIV care (called the HIV cascade of care or HIV care continuum), as follows:

  • diagnosis of HIV
  • linkage to care
  • retention in care
  • adherence to ART
  • suppression of HIV (viral suppression)

Researchers found that at the start of the study 32% of participants reported being homeless. Analysis found that homelessness itself was not a barrier to being linked to HIV care. However, people experiencing homelessness were significantly less likely to use ART than people who had housing. Furthermore, if they received ART, people experiencing homelessness were less likely to remain on treatment and subsequently achieve a suppressed viral load.

Statistical analysis found that, overall, people experiencing homelessness had a 44% lower chance of progressing through the HIV cascade of care. The greatest effect of homelessness was on being able to reach an undetectable viral load. Researchers estimated that people experiencing homelessness had a 54% lower chance of having an undetectable viral load.

Engaging in basic survival needs

The Vancouver researchers advanced the following ideas to account for their findings:

“The daily challenges of securing basic survival needs including shelter may take precedence over other health needs such as engaging in HIV care. People who are homeless may be more likely to engage in survival-based income-generating activities such as sex work and [selling drugs]. Criminalization of these behaviours, as well as intersecting HIV and substance-use-related stigma have been shown to create barriers to HIV care and ART access.”

The researchers added that “people who are homeless tend to have increased psychiatric comorbidities and engage in higher intensity substance use, both of which can limit engagement with health services.”

An important point advanced by the researchers is that “even after accessing HIV care and ART, the lack of a safe space to store medication and lack of privacy [to take medication] may interfere with ART adherence.”

Recent vs. longer lack of housing

The researchers found that people who had recently experienced homelessness were largely still able to move through the HIV cascade of care. However, people who had experienced homelessness for longer periods were less likely to progress through the HIV care continuum. The researchers suggest that the impact of homelessness “may be more significant among people who have experienced greater cumulative exposure to the challenges and harms associated with material insecurity, unstable housing and transient living.” Previous research by the same team has found that people with longer durations of homelessness were less likely to achieve an undetectable viral load.

Possible solutions

The researchers made several suggestions that community organizations and governments need to explore. They stated that a priority would be “housing first services.” Such services “would provide permanent and subsidized housing for persons with health challenges without requiring prior treatment [for] sobriety.”

The researchers suggested the provision of patient navigation services to help people access housing and care for HIV, substance use and mental health issues.

According to the researchers, previous studies have found that street outreach programs “that provide HIV counselling, case management, low-barrier medical care, and mental health and substance use treatment” have demonstrated the ability to improve the likelihood of reaching an undetectable viral load among people with HIV who use drugs.

Although not mentioned by the researchers, a study has found that long-acting ART together with extensive support services was able to help many people who face multiple challenges reach an undetectable viral load.

In the absence of policies and programs that address the various structural issues, particularly housing, faced by people with HIV who use drugs, it will be difficult for Canada, the U.S. and other countries to help all people with HIV achieve the full benefits of ART.

—Sean R. Hosein


Study confirms that long-acting injectable HIV treatment can work in people with multiple challengesCATIE News

Harm Reduction Fundamentals: A toolkit for service providers — CATIE

BC Centre on Substance Use

B.C. Centre for Excellence in HIV/AIDS


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